Rottlerin enhances IL-1β-induced COX-2 expression through sustained p38 MAPK activation in MDA-MB-231 human breast cancer cells

PubMed Central

Park, Eun Jung

2011-01-01

Cyclooxygenase-2 (COX-2) is an important enzyme in inflammation. In this study, we investigated the underlying molecular mechanism of the synergistic effect of rottlerin on interleukin1β (IL-1β)-induced COX-2 expression in MDA-MB-231 human breast cancer cell line. Treatment with rottlerin enhanced IL-1β-induced COX-2 expression at both the protein and mRNA levels. Combined treatment with rottlerin and IL-1β significantly induced COX-2 expression, at least in part, through the enhancement of COX-2 mRNA stability. In addition, rottlerin and IL-1β treatment drove sustained activation of p38 Mitogen-activated protein kinase (MAPK), which is involved in induced COX-2 expression. Also, a pharmacological inhibitor of p38 MAPK (SB 203580) and transient transfection with inactive p38 MAPK inhibited rottlerin and IL-1β-induced COX-2 upregulation. However, suppression of protein kinase C δ (PKC δ) expression by siRNA or overexpression of dominant-negative PKC δ (DN-PKC-δ) did not abrogate the rottlerin plus IL-1β-induced COX-2 expression. Furthermore, rottlerin also enhanced tumor necrosis factor-α (TNF-α), phorbol myristate acetate (PMA), and lipopolysaccharide (LPS)-induced COX-2 expression. Taken together, our results suggest that rottlerin causes IL-1β-induced COX-2 upregulation through sustained p38 MAPK activation in MDA-MB-231 human breast cancer cells. PMID:21971413

The relationship between cyclooxygenase-2 expression and characteristics of malignant transformation in human colorectal adenomas.

PubMed

Sheehan, Katherine M; O'Connell, Fionnuala; O'Grady, Anthony; Conroy, Ronan M; Leader, Mary B; Byrne, Michael F; Murray, Frank E; Kay, Elaine W

2004-06-01

Cyclooxygenase 2 (COX-2) is a target of aspirin and other non-steroidal anti-inflammatory drugs and is implicated in the pathogenesis of colorectal cancer. The objective of this study was to evaluate the extent of COX-2 in pre-malignant colorectal polyps and to assess the relationship between COX-2 and the level of dysplasia in these lesions. Whole polypectomy specimens were retrieved from 123 patients by endoscopic or surgical resection. Following formalin fixation and paraffin embedding, the polyps were evaluated histologically for size, type and grade of dysplasia. The extent of COX-2 expression was measured by the avidin-biotin immunohistochemical technique using a monoclonal COX-2 antibody. The extent of COX-2 expression was graded according to percentage epithelial COX-2 expression. The polyps were of the following histological types: 10 hyperplastic, 35 tubular adenomas, 61 tubulovillous adenomas and 17 villous adenomas. Twenty showed mild dysplasia, 65 moderate dysplasia, and 28 focal or severe dysplasia (including eight with focal invasion). The average polyp size was 1.7 cm. Nine hyperplastic polyps were COX-2-negative and one was COX-2-positive. COX-2 expression was more extensive in larger polyps and in polyps with a higher villous component. There was a significant increase in the extent of COX-2 protein with increasing severity of dysplasia. Within a polyp, there was a focal corresponding increase in COX-2 expression within epithelium showing a higher grade of dysplasia. COX-2 expression is related directly to colorectal adenomatous polyp size, type and grade of dysplasia. This suggests that the role of COX-2 in colorectal cancer may be at an early stage in the adenoma-to-carcinoma sequence and supports the suggestion that inhibition of COX-2 may be useful chemoprevention for this disease.

Constitutively expressed COX-2 in osteoblasts positively regulates Akt signal transduction via suppression of PTEN activity.

PubMed

Li, Ching-Ju; Chang, Je-Ken; Wang, Gwo-Jaw; Ho, Mei-Ling

2011-02-01

Cyclooxygenase-2 (COX-2) is thought to be an inducible enzyme, but increasing reports indicate that COX-2 is constitutively expressed in several organs. The status of COX-2 expression in bone and its physiological role remains undefined. Non-selective non-steroidal anti-inflammatory drugs (NSAIDs) and selective COX-2 inhibitors, which commonly suppress COX-2 activity, were reported to suppress osteoblast proliferation via Akt/FOXO3a/p27(Kip1) signaling, suggesting that COX-2 may be the key factor of the suppressive effects of NSAIDs on proliferation. Although Akt activation correlates with PTEN deficiency and cell viability, the role of COX-2 on PTEN/Akt regulation remains unclear. In this study, we hypothesized that COX-2 may be constitutively expressed in osteoblasts and regulate PTEN/Akt-related proliferation. We examined the localization and co-expression of COX-2 and p-Akt in normal mouse femurs and in cultured mouse (mOBs) and human osteoblasts (hOBs). Our results showed that osteoblasts adjacent to the trabeculae, periosteum and endosteum in mouse femurs constitutively expressed COX-2, while COX-2 co-expressed with p-Akt in osteoblasts sitting adjacent to trabeculae in vivo, and in mOBs and hOBs in vitro. We further used COX-2 siRNA to test the role of COX-2 in Akt signaling in hOBs; COX-2 silencing significantly inhibited PTEN phosphorylation, enhanced PTEN activity, and suppressed p-Akt level and proliferation. However, replenishment of the COX-2 enzymatic product, PGE2, failed to reverse COX-2-dependent Akt phosphorylation. Furthermore, transfection with recombinant human COX-2 (rhCOX-2) significantly reversed COX-2 siRNA-suppressed PTEN phosphorylation, but this effect was reduced when the enzymatic activity of rhCOX-2 was blocked. This finding indicated that the effect of COX-2 on PTEN/Akt signaling is not related to PGE2 but still dependent on COX-2 enzymatic activity. Conversely, COX-1 silencing did not affect PTEN/Akt signaling. Our findings provide new insight into bone physiology; namely, that COX-2 is constitutively expressed in osteoblasts in the dynamic bone growth area, which facilitates osteoblast proliferation via PTEN/Akt/p27(Kip1) signaling. Copyright © 2010 Elsevier Inc. All rights reserved.

Neuronal overexpression of cyclooxygenase-2 does not alter the neuroinflammatory response during brain innate immune activation.

PubMed

Aid, Saba; Parikh, Nishant; Palumbo, Sara; Bosetti, Francesca

2010-07-12

Neuroinflammation is a critical component in the progression of several neurological and neurodegenerative diseases and cyclooxygenases (COX)-1 and -2 are key regulators of innate immune responses. We recently demonstrated that COX-1 deletion attenuates, whereas COX-2 deletion enhances, the neuroinflammatory response, blood-brain barrier permeability and leukocyte recruitment during lipopolysaccharide (LPS)-induced innate immune activation. Here, we used transgenic mice, which overexpressed human COX-2 via neuron-specific Thy-1 promoter (TgCOX-2), causing elevated prostaglandins (PGs) levels. We tested whether neuronal COX-2 overexpression affects the glial response to a single intracerebroventricular injection of LPS, which produces a robust neuroinflammatory reaction. Relative to non-transgenic controls (NTg), 7 month-old TgCOX-2 did not show any basal neuroinflammation, as assessed by gene expression of markers of inflammation and oxidative stress, neuronal damage, as assessed by Fluoro-JadeB staining, or systemic inflammation, as assessed by plasma levels of IL-1beta and corticosterone. Twenty-four hours after LPS injection, all mice showed increased microglial activation, as indicated by Iba1 immunostaining, neuronal damage, mRNA expression of cytokines (TNF-alpha, IL-6), reactive oxygen expressing enzymes (iNOS and NADPH oxidase subunits), endogenous COX-2, cPLA(2) and mPGES-1, and hippocampal and cortical IL-1beta levels. However, the increases were similar in TgCOX-2 and NTg. In NTg, LPS increased brain PGE(2) to the levels observed in TgCOX-2. These results suggest that PGs derived from neuronal COX-2 do not play a role in the neuroinflammatory response to acute activation of brain innate immunity. This is likely due to the direct effect of LPS on glial rather than neuronal cells. Published by Elsevier Ireland Ltd.

Ku80 cooperates with CBP to promote COX-2 expression and tumor growth

PubMed Central

Qin, Yu; Xuan, Yang; Jia, Yunlu; Hu, Wenxian; Yu, Wendan; Dai, Meng; Li, Zhenglin; Yi, Canhui; Zhao, Shilei; Li, Mei; Du, Sha; Cheng, Wei; Xiao, Xiangsheng; Chen, Yiming; Wu, Taihua; Meng, Songshu; Yuan, Yuhui; Liu, Quentin; Huang, Wenlin; Guo, Wei; Wang, Shusen; Deng, Wuguo

2015-01-01

Cyclooxygenase-2 (COX-2) plays an important role in lung cancer development and progression. Using streptavidin-agarose pulldown and proteomics assay, we identified and validated Ku80, a dimer of Ku participating in the repair of broken DNA double strands, as a new binding protein of the COX-2 gene promoter. Overexpression of Ku80 up-regulated COX-2 promoter activation and COX-2 expression in lung cancer cells. Silencing of Ku80 by siRNA down-regulated COX-2 expression and inhibited tumor cell growth in vitro and in a xenograft mouse model. Ku80 knockdown suppressed phosphorylation of ERK, resulting in an inactivation of the MAPK pathway. Moreover, CBP, a transcription co-activator, interacted with and acetylated Ku80 to co-regulate the activation of COX-2 promoter. Overexpression of CBP increased Ku80 acetylation, thereby promoting COX-2 expression and cell growth. Suppression of CBP by a CBP-specific inhibitor or siRNA inhibited COX-2 expression as well as tumor cell growth. Tissue microarray immunohistochemical analysis of lung adenocarcinomas revealed a strong positive correlation between levels of Ku80 and COX-2 and clinicopathologic variables. Overexpression of Ku80 was associated with poor prognosis in patients with lung cancers. We conclude that Ku80 promotes COX-2 expression and tumor growth and is a potential therapeutic target in lung cancer. PMID:25797267

Up-regulation of cyclooxygenase-2 by product-prostaglandin E2

NASA Technical Reports Server (NTRS)

Tjandrawinata, R. R.; Hughes-Fulford, M.

1997-01-01

The development of prostate cancer has been linked to high level of dietary fat intake. Our laboratory investigates the connection between cancer cell growth and fatty acid products. Studying human prostatic carcinoma PC-3 cells, we found that prostaglandin E2 (PGE2) increased cell growth and up-regulated the gene expression of its own synthesizing enzyme, cyclooxygenase-2 (COX-2). PGE2 increased COX-2 mRNA expression dose-dependently with the highest levels of stimulation seen at the 3-hour period following PGE2 addition. The NSAID flurbiprofen (5 microM), in the presence of exogenous PGE2, inhibited the up-regulation of COX-2 mRNA and cell growth. These data suggest that the levels of local intracellular PGE2 play a major role in the growth of prostate cancer cells through an activation of COX-2 gene expression.

Caveolin-1–mediated Suppression of Cyclooxygenase-2 via a β-catenin-Tcf/Lef–dependent Transcriptional Mechanism Reduced Prostaglandin E2 Production and Survivin Expression

PubMed Central

Rodriguez, Diego A.; Tapia, Julio C.; Fernandez, Jaime G.; Torres, Vicente A.; Muñoz, Nicolas; Galleguillos, Daniela; Leyton, Lisette

2009-01-01

Augmented expression of cyclooxygenase-2 (COX-2) and enhanced production of prostaglandin E2 (PGE2) are associated with increased tumor cell survival and malignancy. Caveolin-1 is a scaffold protein that has been proposed to function as a tumor suppressor in human cancer cells, although mechanisms underlying this ability remain controversial. Intriguingly, the possibility that caveolin-1 regulates the expression of COX-2 has not been explored. Here we show that augmented caveolin-1 expression in cells with low basal levels of this protein, such as human colon cancer (HT29, DLD-1), breast cancer (ZR75), and embryonic kidney (HEK293T) cells reduced COX-2 mRNA and protein levels and β-catenin-Tcf/Lef and COX-2 gene reporter activity, as well as the production of PGE2 and cell proliferation. Moreover, COX-2 overexpression or PGE2 supplementation increased levels of the inhibitor of apoptosis protein survivin by a transcriptional mechanism, as determined by PCR analysis, survivin gene reporter assays and Western blotting. Furthermore, addition of PGE2 to the medium prevented effects attributed to caveolin-1–mediated inhibition of β-catenin-Tcf/Lef–dependent transcription. Finally, PGE2 reduced the coimmunoprecipitation of caveolin-1 with β-catenin and their colocalization at the plasma membrane. Thus, by reducing COX-2 expression, caveolin-1 interrupts a feedback amplification loop involving PGE2-induced signaling events linked to β-catenin/Tcf/Lef–dependent transcription of tumor survival genes including cox-2 itself and survivin. PMID:19244345

Correlation analysis between expression of PCNA, Ki-67 and COX-2 and X-ray features in mammography in breast cancer.

PubMed

Qiu, Xiaoming; Mei, Jixin; Yin, Jianjun; Wang, Hong; Wang, Jinqi; Xie, Ming

2017-09-01

This study investigated expression of proliferating cell nuclear antigen (PCNA), proliferation-associated nuclear antigen (Ki-67) and cyclooxygenase-2 (COX-2) in tissues of breast invasive ductal carcinoma, and analyzed the correlations between these indexes and X-ray features in mammography. A total of 90 patients who were admitted to Huangshi Central Hospital and diagnosed as breast invasive ductal carcinoma from January 2014 to January 2016 were selected. The expression of PCNA, Ki-67 and COX-2 in cancer tissues and cancer-adjacent normal tissues of patients were detected by immunohistochemical staining, and X-ray features in mammography of patients were observed. By using Spearman correlation analysis, the correlations between expression of PCNA, Ki-67 and COX-2 and X-ray features in mammography in breast cancer were investigated. As a result, the positive expression rates of PCNA, Ki-67 and COX-2 in cancer tissues of the patient groups were respectively 42.2, 45.6 and 51.1%, which were significantly higher than those in cancer-adjacent normal tissues of the control group (p<0.05). PCNA, Ki-67 and COX-2 expression in cancer tissues of the patient group was associated with clinical staging and lymphatic metastasis (p<0.05), but had no correlation with age and tumor size (p>0.05). PCNA, Ki-67 and COX-2 expression in cancer tissues of the patient group had no correlation with the existence of lumps and localized density-increased shadows (p>0.05), but were associated with manifestations of architectural distortion, calcification as well as skin and nipple depression (p<0.05). Spearman correlation analysis revealed that there was a significantly positive correlation between the expression of PCNA and COX-2 in cancer tissues of the patient group (r=0.676, p<0.05); there was a significantly positive correlation between the expression of Ki-67 and COX-2 (r=0.724, p<0.05); PCNA expression had no obvious correlation with the expression of Ki-67 (p>0.05). In conclusion, PCNA, Ki-67 and COX-2 expression is of great significance in the occurrence, invasion and metastasis of breast invasive ductal carcinoma. There is a strong correlation between PCNA, Ki-67 and COX-2 expression levels and X-ray features in mammography in breast invasive ductal carcinoma. The application of X-ray features in mammography can evaluate the expression levels of PCNA, Ki-67 and COX-2 in tissues of breast invasive ductal carcinoma, thereby prospectively predicting biological behavior of these cancer cells and patient prognosis.

Differential regulation of cyclo-oxygenase-2 and 5-lipoxygenase-activating protein (FLAP) expression by glucocorticoids in monocytic cells.

PubMed

Goppelt-Struebe, M; Schaefer, D; Habenicht, A J

1997-10-01

1. The objective of the present study was to determine the effects of dexamethasone on key constituents of prostaglandin and leukotriene biosynthesis, cyclo-oxygenase-2 (COX-2) and 5-lipoxygenase activating protein (FLAP). The human monocytic cell line THP-1 was used as a model system. mRNA and protein levels of COX-2 and FLAP were determined by Northern and Western blot analyses, respectively. 2. Low levels of COX-2 and FLAP mRNA were expressed in undifferentiated THP-1 cells, but were induced upon differentiation of the cells along the monocytic pathway by treatment with phorbol ester (TPA, 5 nM). Maximal expression was observed after two days. 3. Coincubation of the undifferentiated cells with dexamethasone (10(-9) - 10(-6) M) and phorbol ester prevented induction of COX-2 mRNA, but did not affect the induction of FLAP mRNA. 4. Dexamethasone downregulated COX-2 mRNA and protein in differentiated, monocyte-like THP-1 cells. In contrast, FLAP mRNA and protein were upregulated by dexamethasone in differentiated THP-1 cells. After 24 h, FLAP mRNA levels were increased more than 2 fold. Dexamethasone did not change 5-lipoxygenase mRNA expression. 5. Release of prostaglandin E2 (PGE2) and peptidoleukotrienes was determined in cell culture supernatants of differentiated THP-1 cells by ELISA. Calcium ionophore-dependent PGE2 synthesis was associated with COX-2 expression, whereas COX-1 and COX-2 seemed to participate in arachidonic acid-dependent PGE2 synthesis. Very low levels of peptidoleukotrienes were released from differentiated THP-1 cells upon incubation with ionophore. Treatment with dexamethasone did not significantly affect leukotriene release. 6. These data provide evidence that prostaglandin synthesis is consistently downregulated by glucocorticoids. However, the glucocorticoid-mediated induction of FLAP may provide a mechanism to maintain leukotriene biosynthesis through more efficient transfer of arachidonic acid to the 5-lipoxygenase reaction, in spite of inhibitory effects on other enzymes of the biosynthetic pathway.

Indomethacin-Induced Apoptosis in Esophageal Adenocarcinoma Cells Involves Upregulation of Bax and Translocation of Mitochondrial Cytochrome C Independent of COX-2 Expression1

PubMed Central

Aggarwal, Sanjeev; Taneja, Neelam; Lin, Lin; Orringer, Mark B; Rehemtulla, Alnawaz; Beer, David G

2000-01-01

Abstract The prolonged use of nonsteroidal anti-inflammatory drugs (NSAIDs) has been shown to exert a chemopreventive effect in esophageal and other gastrointestinal tumors. The precise mechanism by which this occurs, however, is unknown. While the inhibition of COX-2 as a potential explanation for this chemopreventive effect has gained a great deal of support, there also exists evidence supporting the presence of cyclooxygenase-independent pathways through which NSAIDs may exert their effects. In this study, immunohistochemical analysis of 29 Barrett's epithelial samples and 60 esophageal adenocarcinomas demonstrated abundant expression of the COX-2 protein in Barrett's epithelium, but marked heterogeneity of expression in esophageal adenocarcinomas. The three esophageal adenocarcinoma cell lines, Flo-1, Bic-1, and Seg-1, also demonstrated varying expression patterns for COX-1 and COX-2. Indomethacin induced apoptosis in all three cell lines, however, in both a time- and dose-dependent manner. In Flo-1 cells, which expressed almost undetectable levels of COX-1 and COX-2, and in Seg-1, which expressed significant levels of COX-1 and COX-2, indomethacin caused upregulation of the pro-apoptotic protein Bax. The upregulation of Bax was accompanied by the translocation of mitochondrial cytochrome c to the cytoplasm, and activation of caspase 9. Pre-treatment of both cell lines with the specific caspase 9 inhibitor, z-LEHD-FMK, as well as the broad-spectrum caspase inhibitor, z-VAD-FMK, blocked the effect of indomethacin-induced apoptosis. These data demonstrate that induction of apoptosis by indomethacin in esophageal adenocarcinoma cells is associated with the upregulation of Bax expression and mitochondrial cytochrome c translocation, and does not correlate with the expression of COX-2. This may have important implications for identifying new therapeutic targets in this deadly disease. PMID:11005569

COX-2 expression positively correlates with PD-L1 expression in human melanoma cells.

PubMed

Botti, Gerardo; Fratangelo, Federica; Cerrone, Margherita; Liguori, Giuseppina; Cantile, Monica; Anniciello, Anna Maria; Scala, Stefania; D'Alterio, Crescenzo; Trimarco, Chiara; Ianaro, Angela; Cirino, Giuseppe; Caracò, Corrado; Colombino, Maria; Palmieri, Giuseppe; Pepe, Stefano; Ascierto, Paolo Antonio; Sabbatino, Francesco; Scognamiglio, Giosuè

2017-02-23

The resistance to PD-1/PD-L1 inhibitors for the treatment of melanoma have prompted investigators to implement novel clinical trials which combine immunotherapy with different treatment modalities. Moreover is also important to investigate the mechanisms which regulate the dynamic expression of PD-L1 on tumor cells and PD-1 on T cells in order to identify predictive biomarkers of response. COX-2 is currently investigated as a major player of tumor progression in several type of malignancies including melanoma. In the present study we investigated the potential relationship between COX-2 and PD-L1 expression in melanoma. Tumor samples obtained from primary melanoma lesions and not matched lymph node metastases were analyzed for both PD-L1 and COX-2 expression by IHC analysis. Status of BRAF and NRAS mutations was analyzed by sequencing and PCR. Co-localization of PD-L1 and COX-2 expression was analyzed by double fluorescence staining. Lastly the BRAF V600E A375 and NRAS Q61R SK-MEL-2 melanoma cell lines were used to evaluate the effect of COX-2 inhibition by celecoxib on expression of PD-L1 in vitro. BRAF V600E/V600K and NRAS Q61R/Q61L were detected in 57.8 and 8.9% of the metastatic lesions, and in 65.9 and 6.8% of the primary tumors, respectively. PD-L1 and COX-2 expression were heterogeneously expressed in both primary melanoma lesions and not matched lymph node metastases. A significantly lower number of PD-L1 negative lesions was found in primary tumors as compared to not matched metastatic lesions (P = 0.002). COX-2 expression significantly correlated with PD-L1 expression in both primary (P = 0.001) and not matched metastatic (P = 0.048) lesions. Furthermore, in melanoma tumors, cancer cells expressing a higher levels of COX-2 also co-expressed a higher level of PD-L1. Lastly, inhibition of COX-2 activity by celecoxib down-regulated the expression of PD-L1 in both BRAF V600E A375 and NRAS Q61R SK-MEL-2 melanoma cell lines. COX-2 expression correlates with and modulates PD-L1 expression in melanoma cells. These findings have clinical relevance since they provide a rationale to implement novel clinical trials to test COX-2 inhibition as a potential treatment to prevent melanoma progression and immune evasion as well as to enhance the anti-tumor activity of PD-1/PD-L1 based immunotherapy for the treatment of melanoma patients with or without BRAF/NRAS mutations.

LY294002 inhibits glucocorticoid-induced COX-2 gene expression in cardiomyocytes through a phosphatidylinositol 3 kinase-independent mechanism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun Haipeng; Xu Beibei; Sheveleva, Elena

2008-10-01

Glucocorticoids induce COX-2 expression in rat cardiomyocytes. While investigating whether phosphatidylinositol 3 kinase (PI3K) plays a role in corticosterone (CT)-induced COX-2, we found that LY294002 (LY29) but not wortmannin (WM) attenuates CT from inducing COX-2 gene expression. Expression of a dominant-negative mutant of p85 subunit of PI3K failed to inhibit CT from inducing COX-2 expression. CT did not activate PI3K/AKT signaling pathway whereas LY29 and WM decreased the activity of PI3K. LY303511 (LY30), a structural analogue and a negative control for PI3K inhibitory activity of LY29, also suppressed COX-2 induction. These data suggest PI3K-independent mechanisms in regulating CT-induced COX-2 expression.more » LY29 and LY30 do not inhibit glucocorticoid receptor transactivity. Both compounds have been reported to inhibit Casein Kinase 2 activity and modulate potassium and calcium levels independent of PI3K, while LY29 has been reported to inhibit mammalian Target of Rapamycin (mTOR), and DNA-dependent Protein Kinase (DNA-PK). Inhibitor of Casein Kinase 2 (CK2), mTOR or DNA-PK failed to prevent CT from inducing COX-2 expression. Tetraethylammonium (TEA), a potassium channel blocker, and nimodipine, a calcium channel blocker, both attenuated CT from inducing COX-2 gene expression. CT was found to increase intracellular Ca{sup 2+} concentration, which can be inhibited by LY29, TEA or nimodipine. These data suggest a possible role of calcium instead of PI3K in CT-induced COX-2 expression in cardiomyocytes.« less

Expression of vitamin D receptor (VDR), cyclooxygenase-2 (COX-2) and 15-hydroxyprostaglandin dehydrogenase (15-PGDH) in benign and malignant ovarian tissue and 25-hydroxycholecalciferol (25(OH2)D3) and prostaglandin E2 (PGE2) serum level in ovarian cancer patients.

PubMed

Thill, Marc; Fischer, Dorothea; Kelling, Katharina; Hoellen, Friederike; Dittmer, Christine; Hornemann, Amadeus; Salehin, Darius; Diedrich, Klaus; Friedrich, Michael; Becker, Steffi

2010-07-01

Ovarian carcinomas are associated with increased inflammation which is based upon an up-regulation of inducible cyclooxygenase-2 (COX-2). Moreover, based on our previous published data, the extra-renal vitamin D metabolism seems to be dysregulated in comparison to healthy tissue. In order to gain further insight into the prostaglandin (PG)- and vitamin D-metabolism in ovarian carcinomas, the study aimed to evaluate the expression of the PG metabolising enzymes COX-2 and 15-hydroxyprostaglandin dehydrogenase (15-PGDH) compared to the vitamin D receptor (VDR) in benign and malignant ovarian tissues. Additionally, we determined the 25-hydroxycholecalciferol (25(OH2)D3) serum levels. Expression of VDR, COX-2 and 15-PGDH was determined by Western blot analysis. Serum levels of 25(OH2)D3 and PGE2 were measured by chemiluminescence-based and colorimetric immunoassay. We detected significantly higher expressions of the PG metabolising enzymes 15-PGDH and COX-2 in malignant tissue and PGE2 serum levels were 2-fold higher in tumour patients. Furthermore, we found an inverse correlation to the VDR-expression which was 62.1% lower in malignant tissues compared to that in benign tissues. Surprisingly, we could not detect any differences between the 25(OH2)D3 serum levels in either group (n=20). These data suggest a correlation between PG- and vitamin D-metabolism in ovarian carcinomas. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

The expression of COX-2, hTERT, MDM2, LATS2 and S100A2 in different types of non-small cell lung cancer (NSCLC).

PubMed

Strazisar, Mojca; Mlakar, Vid; Glavac, Damjan

2009-01-01

Several studies have reported different expression levels of certain genes in NSCLC, mostly related to the stage and advancement of the tumours. We investigated 65 stage I-III NSCLC tumours: 32 adenocarcinomas (ADC), 26 squamous cell carcinomas (SCC) and 7 large cell carcinomas (LCC). Using the real-time reverse transcription polymerase chain reaction (RT-PCR), we analysed the expression of the COX-2, hTERT, MDM2, LATS2 and S100A2 genes and researched the relationships between the NSCLC types and the differences in expression levels. The differences in the expression levels of the LATS2, S100A2 and hTERT genes in different types of NSCLC are significant. hTERT and COX-2 were over-expressed and LATS2 under-expressed in all NSCLC. We also detected significant relative differences in the expression of LATS2 and MDM2, hTERT and MDM2 in different types of NSCLC. There was a significant difference in the average expression levels in S100A2 for ADC and SCC. Our study shows differences in the expression patterns within the NSCLC group, which may mimic the expression of the individual NSCLC type, and also new relationships in the expression levels for different NSCLC types.

Effects of hypo- and hyperthyroidism on proliferation, angiogenesis, apoptosis and expression of COX-2 in the corpus luteum of female rats.

PubMed

Silva, J F; Ocarino, N M; Vieira, A L S; Nascimento, E F; Serakides, R

2013-08-01

Although thyroid dysfunction occurs frequently in humans and some animal species, the mechanisms by which hypo- and hyperthyroidism affect the corpus luteum have not been thoroughly elucidated. This study evaluated the levels of proliferative activity, angiogenesis, apoptosis and expression of cyclooxygenase-2 in the corpus luteum of female rats with thyroid dysfunction. These processes may be important in understanding the reproductive changes caused by thyroid dysfunction. A total of 18 adult female rats were divided into three groups (control, hypothyroid and hyperthyroid) with six animals per group. Three months after treatment to induce thyroid dysfunction, the rats were euthanized in the dioestrus phase. The ovaries were collected and immunohistochemically analysed for expression of the cell proliferation marker CDC-47, vascular endothelial growth factor (VEGF), VEGF receptor Flk-1 and cyclooxygenase-2 (COX-2). Apoptosis was evaluated using the TUNEL assay. Hypothyroidism reduced the intensity and area of COX-2 expression in the corpus luteum (p < 0.05), while hyperthyroidism did not alter COX-2 expression in the dioestrus phase. Hypothyroidism significantly reduced the expression of CDC-47 in endothelial cells and pericytes in the corpus luteum, whereas hyperthyroidism did not induce a detectable change in CDC-47 expression (p > 0.05). Hypothyroidism reduced the level of apoptosis in luteal cells (p < 0.05) and increased VEGF expression in the corpus luteum. In contrast, hyperthyroidism increased the level of apoptosis in the corpus luteum (p < 0.05). In conclusion, thyroid dysfunction differentially affects the levels of proliferative activity, angiogenesis and apoptosis and COX-2 expression in the corpus luteum of female rats. © 2013 Blackwell Verlag GmbH.

Thymoquinone suppresses migration of LoVo human colon cancer cells by reducing prostaglandin E2 induced COX-2 activation.

PubMed

Hsu, Hsi-Hsien; Chen, Ming-Cheng; Day, Cecilia Hsuan; Lin, Yueh-Min; Li, Shin-Yi; Tu, Chuan-Chou; Padma, Viswanadha Vijaya; Shih, Hui-Nung; Kuo, Wei-Wen; Huang, Chih-Yang

2017-02-21

To identify potential anti-cancer constituents in natural extracts that inhibit cancer cell growth and migration. Our experiments used high dose thymoquinone (TQ) as an inhibitor to arrest LoVo (a human colon adenocarcinoma cell line) cancer cell growth, which was detected by cell proliferation assay and immunoblotting assay. Low dose TQ did not significantly reduce LoVo cancer cell growth. Cyclooxygenase 2 (COX-2) is an enzyme that is involved in the conversion of arachidonic acid into prostaglandin E2 (PGE2) in humans. PGE2 can promote COX-2 protein expression and tumor cell proliferation and was used as a control. Our results showed that 20 μmol/L TQ significantly reduced human LoVo colon cancer cell proliferation. TQ treatment reduced the levels of p-PI3K, p-Akt, p-GSK3β, and β-catenin and thereby inhibited the downstream COX-2 expression. Results also showed that the reduction in COX-2 expression resulted in a reduction in PGE2 levels and the suppression of EP2 and EP4 activation. Further analysis showed that TG treatment inhibited the nuclear translocation of β-catenin in LoVo cancer cells. The levels of the cofactors LEF-1 and TCF-4 were also decreased in the nucleus following TQ treatment in a dose-dependent manner. Treatment with low dose TQ inhibited the COX-2 expression at the transcriptional level and the regulation of COX-2 expression efficiently reduced LoVo cell migration. The results were further verified in vivo by confirming the effects of TQ and/or PGE2 using tumor xenografts in nude mice. TQ inhibits LoVo cancer cell growth and migration, and this result highlights the therapeutic advantage of using TQ in combination therapy against colorectal cancer.

MiR-26b Mimic Inhibits Glioma Proliferation In Vitro and In Vivo Suppressing COX-2 Expression.

PubMed

Chen, Zheng-Gang; Zheng, Chuan-Yi; Cai, Wang-Qing; Li, Da-Wei; Ye, Fu-Yue; Zhou, Jian; Wu, Ran; Yang, Kun

2017-08-11

Glioma is the most common malignant tumor of the nervous system. Studies have shown the microRNA (miR)-26b/cyclooxygenase (COX)-2 axis in the development and progression in many tumor cells. Our study aims to investigate the effect and mechanism of miR-26b/COX-2 axis in glioma. Decreased expression of miR-26b with increased level of COX-2 was found in glioma tissues compared with matched normal tissues. A strong negative correlation was observed between the level of miR-26b and COX-2 in 30 glioma tissues. The miR-26b was then overexpressed by transfecting miR-26b mimic into U-373 cells. The invasive cell number and wounld closing rate were reduced in U-373 cells transfected with miR-26b mimic. Besides, COX2 siRNA enhanced the effect of miR-26b mimic in suppressing the expression of p-ERK1 and p-JNK. Finally, the in vivo experiment revealed that miR-26b mimic transfection strongly reduced the tumor growth, tumor volume and the expression of matrix metalloproteinase (MMP)-2, MMP-9). Taken together, our research indicated a miR-26b/COX-2/ERK/JNK axis in regulating the motility of glioma in vitro and in vivo, providing a new sight for treatment of glioma.

Time-dependent changes in the brain arachidonic acid cascade during cuprizone-induced demyelination and remyelination.

PubMed

Palumbo, S; Toscano, C D; Parente, L; Weigert, R; Bosetti, F

2011-07-01

Phospholipases A(2) (PLA(2)) are the enzymatic keys for the activation of the arachidonic acid (AA) cascade and the subsequent synthesis of pro-inflammatory prostanoids (prostaglandins and tromboxanes). Prostanoids play critical roles in the initiation and modulation of inflammation and their levels have been reported increased in several neurological and neurodegenerative disorders, including multiple sclerosis (MS). Here, we aimed to determine whether brain expression PLA(2) enzymes and the terminal prostagland in levels are changed during cuprizone-induced demyelination and in the subsequent remyelination phase. Mice were given the neurotoxicant cuprizone through the diet for six weeks to induce brain demyelination. Then, cuprizone was withdrawn and mice were returned to a normal diet for 6 weeks to allow spontaneous remyelination. We found that after 4-6 weeks of cuprizone, sPLA(2)(V) and cPLA(2), but not iPLA(2)(VI), gene expression was upregulated in the cortex, concomitant with an increase in the expression of astrocyte and microglia markers. Cyclooxygenase (COX)-2 gene expression was consistently upregulated during all the demyelination period, whereas COX-1 sporadically increased only at week 5 of cuprizone exposure. However, we found that at the protein level only sPLA(2)(V) and COX-1 were elevated during demyelination, with COX-1 selectively expressed by activated and infiltrated microglia/macrophages and astrocytes. Levels of PGE(2), PGD(2), PGI(2) and TXB(2) were also increased during demyelination. During remyelination, none of the PLA(2) isoforms was significantly changed, whereas COX-1 and -2 were sporadically upregulated only at the gene expression level. PGE(2), PGI(2) and PGD(2) levels returned to normal, whereas TXB(2) was still upregulated after 3 weeks of cuprizone withdrawal. Our study characterizes for the first time time-dependent changes in the AA metabolic pathway during cuprizone-induced demyelination and the subsequent remyelination and suggests that sPLA(2)(V) is the major isoform contributing to AA release. Published by Elsevier Ltd.

Time-dependent changes in the brain arachidonic acid cascade during cuprizone-induced demyelination and remyelination

PubMed Central

Palumbo, S.; Toscano, C.D.; Parente, L.; Weigert, R.; Bosetti, F.

2011-01-01

Phospholipases A2 (PLA2) are the enzymatic keys for the activation of the arachidonic acid (AA) cascade and the subsequent synthesis of proinflammatory prostanoids (prostaglandins and tromboxanes). Prostanoids play critical roles in the initiation and modulation of inflammation and their levels have been reported increased in several neurological and neurodegenerative disorders, including multiple sclerosis (MS). Here, we aimed to determine whether brain expression PLA2 enzymes and the terminal prostaglandin levels are changed during cuprizone-induced demyelination and in the subsequent remyelination phase. Mice were given the neurotoxicant cuprizone through the diet for six weeks to induce brain demyelination. Then, cuprizone was withdrawn and mice were returned to a normal diet for six weeks to allow spontaneous remyelination. We found that after 4–6 weeks of cuprizone, sPLA2(V) and cPLA2, but not iPLA2(VI), gene expression was upregulated in the cortex, concomitant with an increase in the expression of astrocyte and microglia markers. Cyclooxygenase (COX)-2 gene expression was consistently upregulated during all the demyelination period, whereas COX-1 sporadically increased only at week 5 of cuprizone exposure. However, we found that at the protein level only sPLA2(V) and COX-1 were elevated during demyelination, with COX-1 selectively expressed by activated and infiltrated microglia/macrophages and astrocytes. Levels of PGE2, PGD2, PGI2 and TXB2 were also increased during demyelination. During remyelination, none of the PLA2 isoforms was significantly changed, whereas COX-1 and -2 were sporadically upregulated only at the gene expression level. PGE2, PGI2, and PGD2 levels returned to normal, whereas TXB2 was still upregulated after 3 weeks of cuprizone withdrawal. Our study characterizes for the first time time-dependent changes in the AA metabolic pathway during cuprizone-induced demyelination and the subsequent remyelination and suggests that sPLA2(V) is the major isoform contributing to AA release. PMID:21530210

[Inhibitory effect of nimesulide and oxaliplatin on tumor growth and lymphatic metastasis of transplanted human lung cancer in nude mice].

PubMed

Lang, Zhe; Chen, Gang; Wang, Dong-chang

2012-10-01

This study was designed to evaluate the inhibitory effect of nimesulide in combination with oxaliplatin on tumor growth, expression of COX-2, VEGF-C, VEGFR-3, survivin and β-catenin, and lymphatic metastasis in lung cancer xenograft in nude mice, and to discuss the possible synergistic effect of nimesulide in combination with oxaliplatin. Human lung cancer A549 cells were injected into BALB/c nude mice subcutaneously. Thirty-three healthy male nude mice were randomly divided into 4 groups: the control group, nimesulide group, oxaliplatin group and nimesulide combined with oxaliplatin group. Transplanted tumor tissues were collected and the expressions of COX-2, VEGF-C, VEGFR-3, survivin, β-catenin protein were detected by immunohistochemistry, and RT-PCR assay was used to assess the expression of tumor COX-2, VEGF-C, VEGFR-3, survivin and β-catenin mRNA. SPSS 16.0 was used for statistical analysis. Data were present as (x(-) ± s), and the means were compared by analysis of variance test. Tumor inhibition rates of the nimesulide group, oxaliplatin group and nimesulide + oxaliplatin group were 39.73%, 48.04% and 65.94%, respectively. Immunohistochemical and RT-PCR analysis showed that compared with the control group, the expression levels of COX-2, VEGF-C, VEGFR-3, survivin and β-catenin of the nimesulide group were significantly reduced (all P < 0.05). Compared with the control group, statistical analysis of variance showed that the expression levels of COX-2, VEGF-C and VEGFR-3 of the oxaliplatin group were significantly increased (P < 0.05), the expression levels of survivin and β-catenin protein and mRNA of the oxaliplatin group were significantly reduced (P < 0.05). Compared with the control group, the expression levels of COX-2, VEGF-C, VEGFR-3, survivin and β-catenin of the nimesulide + oxaliplatin group were significantly reduced (all P < 0.05). Both nimesulide alone or in combination with oxaliplatin can significantly inhibit the growth of lung cancer xenografts in nude mice and the expression levels of COX-2, VEGF-C, VEGFR-3, survivin and β-catenin. Oxaliplatin can significantly inhibit the growth of lung cancer xenografts in nude mice, and the expression of survivin and β-catenin. Nimesulide in combination with oxaliplatin enhances the antitumor effect of oxaliplatin.

Cyclooxygenase-2 inhibitor blocks the production of West Nile virus-induced neuroinflammatory markers in astrocytes.

PubMed

Verma, Saguna; Kumar, Mukesh; Nerurkar, Vivek R

2011-03-01

Inflammatory immune responses triggered initially to clear West Nile virus (WNV) infection later become detrimental and contribute to the pathological processes such as blood-brain barrier (BBB) disruption and neuronal death, thus complicating WNV-associated encephalitis (WNVE). It has been demonstrated previously that WNV infection in astrocytes results in induction of multiple matrix metalloproteinases (MMPs), which mediate BBB disruption. Cyclooxygenase (COX) enzymes and their product, prostaglandin E2 (PGE2), modulate neuroinflammation and regulate the production of multiple inflammatory molecules including MMPs. Therefore, this study determined and characterized the pathophysiological consequences of the expression of COX enzymes in human brain cortical astrocytes (HBCAs) following WNV infection. Whilst COX-1 mRNA expression did not change, WNV infection significantly induced RNA and protein expression of COX-2 in HBCAs. Similarly, PGE2 production was also enhanced significantly in infected HBCAs and was blocked in the presence of the COX-2-specific inhibitor NS-398, thus suggesting that COX-2, and not COX-1, was the source of the increased PGE2. Treatment of infected HBCAs with NS-398 attenuated the expression of MMP-1, -3 and -9 in a dose-dependent manner. Similarly, expression of interleukin-1β, -6 and -8, which were markedly elevated in infected HBCAs, exhibited a significant reduction in their levels in the presence of NS-398. These results provide direct evidence that WNV-induced COX-2/PGE2 is involved in modulating the expression of multiple neuroinflammatory mediators, thereby directly linking COX-2 with WNV disease pathogenesis. The ability of COX-2 inhibitors to modulate WNV-induced COX-2 and PGE2 signalling warrants further investigation in an animal model as a potential approach for clinical management of neuroinflammation associated with WNVE.

Reduced COX-2 expression in aged mice is associated with impaired fracture healing.

PubMed

Naik, Amish A; Xie, Chao; Zuscik, Michael J; Kingsley, Paul; Schwarz, Edward M; Awad, Hani; Guldberg, Robert; Drissi, Hicham; Puzas, J Edward; Boyce, Brendan; Zhang, Xinping; O'Keefe, Regis J

2009-02-01

The cellular and molecular events responsible for reduced fracture healing with aging are unknown. Cyclooxygenase 2 (COX-2), the inducible regulator of prostaglandin E(2) (PGE(2)) synthesis, is critical for normal bone repair. A femoral fracture repair model was used in mice at either 7-9 or 52-56 wk of age, and healing was evaluated by imaging, histology, and gene expression studies. Aging was associated with a decreased rate of chondrogenesis, decreased bone formation, reduced callus vascularization, delayed remodeling, and altered expression of genes involved in repair and remodeling. COX-2 expression in young mice peaked at 5 days, coinciding with the transition of mesenchymal progenitors to cartilage and the onset of expression of early cartilage markers. In situ hybridization and immunohistochemistry showed that COX-2 is expressed primarily in early cartilage precursors that co-express col-2. COX-2 expression was reduced by 75% and 65% in fractures from aged mice compared with young mice on days 5 and 7, respectively. Local administration of an EP4 agonist to the fracture repair site in aged mice enhanced the rate of chondrogenesis and bone formation to levels observed in young mice, suggesting that the expression of COX-2 during the early inflammatory phase of repair regulates critical subsequent events including chondrogenesis, bone formation, and remodeling. The findings suggest that COX-2/EP4 agonists may compensate for deficient molecular signals that result in the reduced fracture healing associated with aging.

Cellular density-dependent down-regulation of EP4 prostanoid receptors via the up-regulation of hypoxia-inducible factor-1α in HCA-7 human colon cancer cells.

PubMed

Otake, Sho; Yoshida, Kenji; Seira, Naofumi; Sanchez, Christopher M; Regan, John W; Fujino, Hiromichi; Murayama, Toshihiko

2015-02-01

Increases in prostaglandin E2 (PGE2) and cyclooxygenase-2 (COX-2) levels are features of colon cancer. Among the different E-type prostanoid receptor subtypes, EP4 receptors are considered to play a crucial role in carcinogenesis by, for example, inducing COX-2 when stimulated with PGE2. However, EP4 receptor levels and PGE2-induced cellular responses are inconsistent among the cellular conditions. Therefore, the connections responsible for the expression of EP4 receptors were investigated in the present study by focusing on cell density-induced hypoxia-inducible factor-1α (HIF-1α). The expression of EP4 receptors was examined using immunoblot analysis, quantitative polymerase chain reaction, and reporter gene assays in HCA-7 human colon cancer cells with different cellular densities. The involvement of HIF-1α and its signaling pathways were also examined by immunoblot analysis, reporter gene assays, and with siRNA. We here demonstrated that EP4 receptors as well as EP4 receptor-mediated COX-2 expression levels decreased with an increase in cellular density. In contrast, HIF-1α levels increased in a cellular density-dependent manner. The knockdown of HIF-1α by siRNA restored the expression of EP4 receptors and EP4 receptor-mediated COX-2 in cells at a high density. Thus, the cellular density-dependent increase observed in HIF-1α expression levels reduced the expression of COX-2 by decreasing EP4 receptor levels. This novel regulation mechanism for the expression of EP4 receptors by HIF-1α may provide an explanation for the inconsistent actions of PGE2. The expression levels of EP4 receptors may vary depending on cellular density, which may lead to the differential activation of their signaling pathways by PGE2. Thus, cellular density-dependent PGE2-mediated signaling may determine the fate/stage of cancer cells, i.e., the surrounding environments could define the fate/stage of malignancies associated with colon cancer.

Cellular density-dependent down-regulation of EP4 prostanoid receptors via the up-regulation of hypoxia-inducible factor-1α in HCA-7 human colon cancer cells

PubMed Central

Otake, Sho; Yoshida, Kenji; Seira, Naofumi; Sanchez, Christopher M; Regan, John W; Fujino, Hiromichi; Murayama, Toshihiko

2015-01-01

Increases in prostaglandin E2 (PGE2) and cyclooxygenase-2 (COX-2) levels are features of colon cancer. Among the different E-type prostanoid receptor subtypes, EP4 receptors are considered to play a crucial role in carcinogenesis by, for example, inducing COX-2 when stimulated with PGE2. However, EP4 receptor levels and PGE2-induced cellular responses are inconsistent among the cellular conditions. Therefore, the connections responsible for the expression of EP4 receptors were investigated in the present study by focusing on cell density-induced hypoxia-inducible factor-1α (HIF-1α). The expression of EP4 receptors was examined using immunoblot analysis, quantitative polymerase chain reaction, and reporter gene assays in HCA-7 human colon cancer cells with different cellular densities. The involvement of HIF-1α and its signaling pathways were also examined by immunoblot analysis, reporter gene assays, and with siRNA. We here demonstrated that EP4 receptors as well as EP4 receptor-mediated COX-2 expression levels decreased with an increase in cellular density. In contrast, HIF-1α levels increased in a cellular density-dependent manner. The knockdown of HIF-1α by siRNA restored the expression of EP4 receptors and EP4 receptor-mediated COX-2 in cells at a high density. Thus, the cellular density-dependent increase observed in HIF-1α expression levels reduced the expression of COX-2 by decreasing EP4 receptor levels. This novel regulation mechanism for the expression of EP4 receptors by HIF-1α may provide an explanation for the inconsistent actions of PGE2. The expression levels of EP4 receptors may vary depending on cellular density, which may lead to the differential activation of their signaling pathways by PGE2. Thus, cellular density-dependent PGE2-mediated signaling may determine the fate/stage of cancer cells, i.e., the surrounding environments could define the fate/stage of malignancies associated with colon cancer. PMID:25692008

Upregulation of intrinsic apoptotic pathway in NSAIDs mediated chemoprevention of experimental lung carcinogenesis.

PubMed

Setia, Shruti; Sanyal, Sankar N

2012-01-01

Non-steroidal anti-inflammatory drugs (NSAIDs) act by inhibition of cyclooxygenase-2 (COX-2), which is overexpressed in cancer. The role of COX-2 and apoptosis were evaluated in 9,10-dimethylbenz(a)anthracene (DMBA)-induced lung cancer in rat and chemoprevention with indomethacin, a traditional NSAID and etoricoxib, a selective COX-2 inhibitor. The animals were divided into Control, DMBA, DMBA+ indomethacin and DMBA+ etoricoxib groups. They received a single intratracheal instillation of DMBA while NSAIDs were given orally daily for 32 weeks. Besides morphology and histology of lungs, RT-PCR, western blots and immunohistochemistry were performed for the expression of apoptotic proteins and COX enzymes. Apoptosis was studied by DNA fragmentation and fluorescent staining. The occurrence of tumors and lesions was noted in the DMBA animals, besides constricted alveolar spaces and hyperplasia. COX-1 was found to be uniformly expressed while COX-2 level was raised significantly in DMBA group. The apoptotic proteins, apaf-1, caspase-9 and caspase-3 were highly diminished in DMBA group but restored to normal level in NSAIDs groups. Also, apoptosis was suppressed in carcinogen group by DNA fragmentation analysis and fluorescent staining of the lung cells while co-administration of NSAIDs along with DMBA led to the restoration of apoptosis. DMBA administration to the rats led to tumorigenesis in the lungs, had no effects on COX-1 expression, while elevating the COX-2 levels and suppressing apoptosis. The treatment with NSAIDs led to the amelioration of these effects. However, etoricoxib which is a COX-2 specific inhibitor, was found to be more effective than the traditional NSAID, indomethacin.

Korean Red Ginseng water extract inhibits COX-2 expression by suppressing p38 in acrolein-treated human endothelial cells

PubMed Central

Lee, Seung Eun; Park, Yong Seek

2013-01-01

Cigarette smoke is considered a major risk factor for vascular diseases. There are many toxic compounds in cigarette smoke, including acrolein and other α,β-unsaturated aldehydes, which are regarded as mediators of inflammation and vascular dysfunction. Furthermore, recent studies have revealed that acrolein, an α,β-unsaturated aldehyde in cigarette smoke, induces inflammatory mediator expression, which is known to be related to vascular diseases. In this study, we investigated whether Korean Red Ginseng (KRG) water extract suppressed acrolein-induced cyclooxygenase (COX)-2 expression in human umbilical vein endothelial cells (HUVECs). Acrolein-induced COX-2 expression was accompanied by increased levels of phosphorylated p38 in HUVECs and KRG inhibited COX-2 expression in HUVECs. These results suggest that KRG suppresses acrolein-induced COX-2 expression via inhibition of the p38 mitogen-activated protein kinase signaling pathway. In addition, KRG exhibited an inhibitory effect on acrolein-induced apoptosis, as demonstrated by annexin V–propidium iodide staining and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay. Consistent with these results, KRG may exert a vasculoprotective effect through inhibition of COX-2 expression in acrolein-stimulated human endothelial cells. PMID:24558308

Cell-type-specific roles for COX-2 in UVB-induced skin cancer

PubMed Central

Herschman, Harvey

2014-01-01

In human tumors, and in mouse models, cyclooxygenase-2 (COX-2) levels are frequently correlated with tumor development/burden. In addition to intrinsic tumor cell expression, COX-2 is often present in fibroblasts, myofibroblasts and endothelial cells of the tumor microenvironment, and in infiltrating immune cells. Intrinsic cancer cell COX-2 expression is postulated as only one of many sources for prostanoids required for tumor promotion/progression. Although both COX-2 inhibition and global Cox-2 gene deletion ameliorate ultraviolet B (UVB)-induced SKH-1 mouse skin tumorigenesis, neither manipulation can elucidate the cell type(s) in which COX-2 expression is required for tumorigenesis; both eliminate COX-2 activity in all cells. To address this question, we created Cox-2 flox/flox mice, in which the Cox-2 gene can be eliminated in a cell-type-specific fashion by targeted Cre recombinase expression. Cox-2 deletion in skin epithelial cells of SKH-1 Cox-2 flox/flox;K14Cre + mice resulted, following UVB irradiation, in reduced skin hyperplasia and increased apoptosis. Targeted epithelial cell Cox-2 deletion also resulted in reduced tumor incidence, frequency, size and proliferation rate, altered tumor cell differentiation and reduced tumor vascularization. Moreover, Cox-2 flox/flox;K14Cre + papillomas did not progress to squamous cell carcinomas. In contrast, Cox-2 deletion in SKH-1 Cox-2 flox/flox; LysMCre + myeloid cells had no effect on UVB tumor induction. We conclude that (i) intrinsic epithelial COX-2 activity plays a major role in UVB-induced skin cancer, (ii) macrophage/myeloid COX-2 plays no role in UVB-induced skin cancer and (iii) either there may be another COX-2-dependent prostanoid source(s) that drives UVB skin tumor induction or there may exist a COX-2-independent pathway(s) to UVB-induced skin cancer. PMID:24469308

Cell-type-specific roles for COX-2 in UVB-induced skin cancer.

PubMed

Jiao, Jing; Mikulec, Carol; Ishikawa, Tomo-o; Magyar, Clara; Dumlao, Darren S; Dennis, Edward A; Fischer, Susan M; Herschman, Harvey

2014-06-01

In human tumors, and in mouse models, cyclooxygenase-2 (COX-2) levels are frequently correlated with tumor development/burden. In addition to intrinsic tumor cell expression, COX-2 is often present in fibroblasts, myofibroblasts and endothelial cells of the tumor microenvironment, and in infiltrating immune cells. Intrinsic cancer cell COX-2 expression is postulated as only one of many sources for prostanoids required for tumor promotion/progression. Although both COX-2 inhibition and global Cox-2 gene deletion ameliorate ultraviolet B (UVB)-induced SKH-1 mouse skin tumorigenesis, neither manipulation can elucidate the cell type(s) in which COX-2 expression is required for tumorigenesis; both eliminate COX-2 activity in all cells. To address this question, we created Cox-2(flox/flox) mice, in which the Cox-2 gene can be eliminated in a cell-type-specific fashion by targeted Cre recombinase expression. Cox-2 deletion in skin epithelial cells of SKH-1 Cox-2(flox/flox);K14Cre(+) mice resulted, following UVB irradiation, in reduced skin hyperplasia and increased apoptosis. Targeted epithelial cell Cox-2 deletion also resulted in reduced tumor incidence, frequency, size and proliferation rate, altered tumor cell differentiation and reduced tumor vascularization. Moreover, Cox-2(flox/flox);K14Cre(+) papillomas did not progress to squamous cell carcinomas. In contrast, Cox-2 deletion in SKH-1 Cox-2(flox/flox); LysMCre(+) myeloid cells had no effect on UVB tumor induction. We conclude that (i) intrinsic epithelial COX-2 activity plays a major role in UVB-induced skin cancer, (ii) macrophage/myeloid COX-2 plays no role in UVB-induced skin cancer and (iii) either there may be another COX-2-dependent prostanoid source(s) that drives UVB skin tumor induction or there may exist a COX-2-independent pathway(s) to UVB-induced skin cancer. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

COX-2 expression mediated by calcium-TonEBP signaling axis under hyperosmotic conditions serves osmoprotective function in nucleus pulposus cells.

PubMed

Choi, Hyowon; Chaiyamongkol, Weera; Doolittle, Alexandra C; Johnson, Zariel I; Gogate, Shilpa S; Schoepflin, Zachary R; Shapiro, Irving M; Risbud, Makarand V

2018-06-08

The nucleus pulposus (NP) of intervertebral discs experiences dynamic changes in tissue osmolarity because of diurnal loading of the spine. TonEBP/NFAT5 is a transcription factor that is critical in osmoregulation as well as survival of NP cells in the hyperosmotic milieu. The goal of this study was to investigate whether cyclooxygenase-2 (COX-2) expression is osmoresponsive and dependent on TonEBP, and whether it serves an osmoprotective role. NP cells up-regulated COX-2 expression in hyperosmotic media. The induction of COX-2 depended on elevation of intracellular calcium levels and p38 MAPK pathway, but independent of calcineurin signaling as well as MEK/ERK and JNK pathways. Under hyperosmotic conditions, both COX-2 mRNA stability and its proximal promoter activity were increased. The proximal COX-2 promoter (-1840/+123 bp) contained predicted binding sites for TonEBP, AP-1, NF-κB, and C/EBP-β. While COX-2 promoter activity was positively regulated by both AP-1 and NF-κB, AP-1 had no effect and NF-κB negatively regulated COX-2 protein levels under hyperosmotic conditions. On the other hand, TonEBP was necessary for both COX-2 promoter activity and protein up-regulation in response to hyperosmotic stimuli. Ex vivo disc organ culture studies using hypomorphic TonEBP +/- mice confirmed that TonEBP is required for hyperosmotic induction of COX-2. Importantly, the inhibition of COX-2 activity under hyperosmotic conditions resulted in decreased cell viability, suggesting that COX-2 plays a cytoprotective and homeostatic role in NP cells for their adaptation to dynamically loaded hyperosmotic niches. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

The cyclooxygenase-2 inhibitor parecoxib inhibits surgery-induced proinflammatory cytokine expression in the hippocampus in aged rats.

PubMed

Peng, Mian; Wang, Yan-Lin; Wang, Fei-Fei; Chen, Chang; Wang, Cheng-Yao

2012-11-01

Neuroinflammatory response triggered by surgery has been increasingly reported to be associated with postoperative cognitive dysfunction. Proinflammatory cytokines, such as interleukin 1β (IL-1β) and tumor necrosis factor α (TNF-α), play a pivotal role in mediating surgery-induced neuroinflammation. The role of cyclooxygenase-2 (COX-2), a critical regulator in inflammatory response, in surgery-induced neuroinflammation is still unknown. The aim of the study was to investigate the changes of COX-2 expression and prostaglandin E2 (PGE2) production in the hippocampus in aged rats following partial hepatectomy. The effects of selective COX-2 inhibitor (parecoxib) on hippocampal proinflammatory cytokine expression were also evaluated. Aged rats were randomly divided into three groups: control (n = 10), surgery (n = 30), and parecoxib (n = 30). Control animals received sterile saline to control for the effects of injection stress. Rats in the surgery group received partial hepatectomy under isoflurane anesthesia and sterile saline injection. Rats in the parecoxib group received surgery and anesthesia similar to surgery group rats, and parecoxib treatment. On postanesthetic days 1, 3, and 7, animals were euthanized to assess levels of hippocampal COX-2 expression, PGE2 production, and cytokines IL-1β and TNF-α expression. The effects of parecoxib on proinflammatory cytokine expression were also assessed. Partial hepatectomy significantly increased COX-2 expression, PGE2 production, and proinflammatory cytokine expression in the hippocampus in aged rats on postoperative days 1 and 3. Parecoxib inhibited hippocampal IL-1β and TNF-α expression through downregulation of the COX-2/PGE2 pathway. COX-2 may play a critical role in surgery-induced neuroinflammation. The COX-2 inhibitor may be a promising candidate for treatment of neuroinflammation caused by surgical trauma. Copyright © 2012 Elsevier Inc. All rights reserved.

Flow cytometric analysis of platelet cyclooxygenase-1 and -2 and surface glycoproteins in patients with immune thrombocytopenia and healthy individuals.

PubMed

Rubak, Peter; Kristensen, Steen D; Hvas, Anne-Mette

2017-06-01

Immature platelets may contain more platelet enzymes such as cyclooxygenase (COX)-1 and COX-2 than mature platelets. Patients with immune thrombocytopenia (ITP) have a higher fraction of immature platelets and can therefore be utilized as a biological model for investigating COX-1 and COX-2 platelet expression. The aims were to develop flow cytometric assays for platelet COX-1 and COX-2 and to investigate the COX-1 and COX-2 platelet expression, platelet turnover, and platelet glycoproteins in ITP patients (n = 10) compared with healthy individuals (n = 30). Platelet count and platelet turnover parameters (mean platelet volume (MPV), immature platelet fraction (IPF), and immature platelet count (IPC)) were measured by flow cytometry (Sysmex XE-5000). Platelet COX-1, COX-2, and the glycoproteins (GP)IIb, IX, Ib, Ia, and IIIa were all analyzed by flow cytometry (Navios) and expressed as median fluorescence intensity. COX analyses were performed in both whole blood and platelet rich plasma (PRP), whereas platelet glycoproteins were analyzed in whole blood only. ITP patients had significantly lower platelet count (55 × 10 9 /L) than healthy individuals (240 × 10 9 /L, p < 0.01), but a higher MPV (p = 0.03) and IPF (p < 0.01). IPC was similar for the two groups (p = 0.74). PRP had significantly lower MPV (p < 0.01) and significantly higher platelet count and IPC (both p-values <0.03) when compared with whole blood. IPF was similar for PRP and whole blood (p = 0.18). COX-1 expression was 10 times higher and COX-2 expression was 50% higher in PRP than in whole blood (p COX-1 < 0.01, p COX-2 < 0.01). Platelet COX-1 expression was higher in ITP patients than healthy individuals using whole blood (p COX-1 < 0.01) and PRP, though this was nonsignificant in PRP (p COX-1 = 0.17). In ITP patients, positive correlations were found between platelet turnover and COX-1 expression (all p-values <0.01, rho = 0.80-0.94), whereas healthy individuals showed significant though weaker correlations between platelet turnover and COX-1 and COX-2 expressions (all p-values <0.03, rho = 0.44-0.71). GPIIb, IX, and Ib expression was increased in ITP patients compared with healthy individuals (all p-values < 0.03). GPIIb, IX, Ib, and IIIa showed positive correlations with platelet turnover in ITP patients (all p-values <0.02, rho = 0.71-0.94), but weak and nonsignificant correlations in healthy individuals (all p-values >0.14, rho = 0.11-0.28). In conclusion, ITP patients expressed higher COX-1 and platelet glycoprotein levels than healthy individuals. COX-1 and platelet glycoproteins demonstrated positive correlations with platelet turnover in ITP patients. In healthy individuals, COX-1 and COX-2 expression correlated positively with platelet turnover. PRP was more sensitive compared with whole blood as regards determination of COX. Therefore, PRP is the recommended matrix for investigating COX-1 and COX-2 in platelets.

Paclitaxel-induced lung injury and its amelioration by parecoxib sodium.

PubMed

Liu, Wen-jie; Zhong, Zhong-jian; Cao, Long-hui; Li, Hui-ting; Zhang, Tian-hua; Lin, Wen-qian

2015-08-10

To investigate the mechanism of paclitaxel-induced lung injury and its amelioration by parecoxib sodium. In this study, rats were randomly divided into: the control group (Con); the paclitaxel chemotherapy group (Pac); the paclitaxel+ parecoxib sodium intervention group (Pac + Pare); and the parecoxib sodium group (Pare). We observed changes in alveolar ventilation function, alveolar-capillary membrane permeability, lung tissue pathology and measured the levels of inflammatory cytokines and cyclooxygenase-2 (Cox-2) in lung tissue, the expression of tight junction proteins (Zo-1 and Claudin-4). Compared with the Con group, the lung tissue of the Pac group showed significantly increased expression of Cox-2 protein (p < 0.01), significant lung tissue inflammatory changes, significantly increased expression of inflammatory cytokines, decreased expression of Zo-1 and Claudin-4 proteins (p < 0.01), increased alveolar-capillary membrane permeability (p < 0.01), and reduced ventilation function (p < 0.01). Notably, in Pac + Pare group, intraperitoneal injection of parecoxib sodium led to decreased Cox-2 and ICAM-1 levels and reduced inflammatory responses, the recovered expression of Zo-1 and Claudin-4, reduced level of indicators reflecting the high permeability state, and close-to-normal levels of ventilation function. Intervention by the Cox-2-specific inhibitor parecoxib sodium can block this damage.

Paclitaxel-induced lung injury and its amelioration by parecoxib sodium

PubMed Central

Liu, Wen-jie; Zhong, Zhong-jian; Cao, Long-hui; Li, Hui-ting; Zhang, Tian-hua; Lin, Wen-qian

2015-01-01

To investigate the mechanism of paclitaxel-induced lung injury and its amelioration by parecoxib sodium. In this study, rats were randomly divided into: the control group (Con); the paclitaxel chemotherapy group (Pac); the paclitaxel+ parecoxib sodium intervention group (Pac + Pare); and the parecoxib sodium group (Pare). We observed changes in alveolar ventilation function, alveolar-capillary membrane permeability, lung tissue pathology and measured the levels of inflammatory cytokines and cyclooxygenase-2 (Cox-2) in lung tissue, the expression of tight junction proteins (Zo-1 and Claudin-4). Compared with the Con group, the lung tissue of the Pac group showed significantly increased expression of Cox-2 protein (p < 0.01), significant lung tissue inflammatory changes, significantly increased expression of inflammatory cytokines, decreased expression of Zo-1 and Claudin-4 proteins (p < 0.01), increased alveolar-capillary membrane permeability (p < 0.01), and reduced ventilation function (p < 0.01). Notably, in Pac + Pare group, intraperitoneal injection of parecoxib sodium led to decreased Cox-2 and ICAM-1 levels and reduced inflammatory responses, the recovered expression of Zo-1 and Claudin-4, reduced level of indicators reflecting the high permeability state, and close-to-normal levels of ventilation function. Intervention by the Cox-2-specific inhibitor parecoxib sodium can block this damage. PMID:26256764

Rofecoxib modulates multiple gene expression pathways in a clinical model of acute inflammatory pain

PubMed Central

Wang, Xiao-Min; Wu, Tian-Xia; Hamza, May; Ramsay, Edward S.; Wahl, Sharon M.; Dionne, Raymond A.

2007-01-01

New insights into the biological properties of cyclooxygenase-2 (COX-2) and its response pathway challenge the hypothesis that COX-2 is simply pro-inflammatory and inhibition of COX-2 solely prevents the development of inflammation and ameliorates inflammatory pain. The present study performed a comprehensive analysis of gene/protein expression induced by a selective inhibitor of COX-2, rofecoxib, compared with a non-selective COX inhibitor, ibuprofen, and placebo in a clinical model of acute inflammatory pain (the surgical extraction of impacted third molars) using microarray analysis followed by quantitative RT-PCR verification and Western blotting. Inhibition of COX-2 modulated gene expression related to inflammation and pain, the arachidonic acid pathway, apoptosis/angiogenesis, cell adhesion and signal transduction. Compared to placebo, rofecoxib treatment increased the gene expression of ANXA3 (annexin 3), SOD2 (superoxide dismutase 2), SOCS3 (suppressor of cytokine signaling 3) and IL1RN (IL1 receptor antagonist) which are associated with inhibition of phospholipase A2 and suppression of cytokine signaling cascades, respectively. Both rofecoxib and ibuprofen treatment increased the gene expression of the pro-inflammatory mediators, IL6 and CCL2 (chemokine C-C motif ligand 2), following tissue injury compared to the placebo treatment. These results indicate a complex role for COX-2 in the inflammatory cascade in addition to the well-characterized COX-dependent pathway, as multiple pathways are also involved in rofecoxib-induced anti-inflammatory and analgesic effects at the gene expression level. These findings may also suggest an alternative hypothesis for the adverse effects attributed to selective inhibition of COX-2. PMID:17070997

Long non-coding RNA cox-2 prevents immune evasion and metastasis of hepatocellular carcinoma by altering M1/M2 macrophage polarization.

PubMed

Ye, Yibiao; Xu, Yunxiuxiu; Lai, Yu; He, Wenguang; Li, Yanshan; Wang, Ruomei; Luo, Xinxi; Chen, Rufu; Chen, Tao

2018-03-01

Macrophages have been shown to demonstrate a high level of plasticity, with the ability to undergo dynamic transition between M1 and M2 polarized phenotypes. We investigate long non-coding RNA (lncRNA) cox-2 in macrophage polarization and the regulatory mechanism functions in hepatocellular carcinoma (HCC). Lipopolysaccharide (LPS) was used to induce RAW264.7 macrophages into M1 type, and IL-4 was to induce RAW264.7 macrophages into M2 type. We selected mouse hepatic cell line Hepal-6 and hepatoma cell line HepG2 for co-incubation with M1 or M2 macrophages. Quantitative real-time PCR was used to detect the expressions of lncRNA cox-2 and mRNAs. ELISA was conducted for testing IL-12 and IL-10 expressions; Western blotting for epithelial mesenchymal transition related factors (E-cadherin and Vimentin). An MTT, colony formation assay, flow cytometry, transwell assay, and stretch test were conducted to test cell abilities. The M1 macrophages had higher lncRNA cox-2 expression than that in the non-polarized macrophages and M2 macrophages. The lncRNA cox-2 siRNA decreased the expression levels of IL-12, iNOS, and TNF-α in M1 macrophages, increased the expression levels of IL-10, Arg-1, and Fizz-1 in M2 macrophages (all P < 0.05). The lncRNA cox-2 siRNA reduces the ability of M1 macrophages to inhibit HCC cell proliferation, invasion, migration, EMT, angiogenesis and facilitate apoptosis while strengthening the ability of M2 macrophages to promote proliferation HCC cell growth and inhibit apoptosis. These findings indicate that lncRNA cox-2 inhibits HCC immune evasion and tumor growth by inhibiting the polarization of M2 macrophages. © 2017 Wiley Periodicals, Inc.

Resveratrol decreases noise-induced cyclooxygenase-2 expression in the rat cochlea.

PubMed

Seidman, Michael D; Tang, Wenxue; Bai, Venkatesh Uma; Ahmad, Nadir; Jiang, Hao; Media, Joseph; Patel, Nimisha; Rubin, Cory J; Standring, Robert T

2013-05-01

Our previous studies have demonstrated the efficacy of resveratrol, a grape constituent noted for its antioxidant and anti-inflammatory properties, in reducing temporary threshold shifts and decreasing cochlear hair cell damage following noise exposure. This study was designed to identify the potential protective mechanism of resveratrol by measuring its effect on cyclooxygenase-2 (COX-2) protein expression and reactive oxygen species (ROS) formation following noise exposure. Controlled animal intervention study. Otology Laboratory, Henry Ford Health System. Twenty-two healthy male Fischer 344 rats (2-3 months old) were exposed to acoustic trauma of variable duration with or without intervention. An additional 20 healthy male rats were used to study COX-2 expression at different time points during and following treatment of 24 hours of noise exposure. Cochlear harvest was performed at various time intervals for measurement of COX-2 protein expression via Western blot analysis and immunostaining. Peripheral blood was also obtained for ROS analysis using flow cytometry. Acoustic trauma exposure resulted in a progressive up-regulation of COX-2 protein expression, commencing at 8 hours and peaking at 32 hours. Similarly, ROS production increased after noise exposure. However, treatment with resveratrol reduced noise-induced COX-2 expression as well as ROS formation in the blood as compared with the controls. COX-2 levels are induced dramatically following noise exposure. This increased expression may be a potential mechanism of noise-induced hearing loss (NIHL) and a possible mechanism of resveratrol's ability to mitigate NIHL by its ability to reduce COX-2 expression.

Exogenous hydrogen sulfide promotes hepatocellular carcinoma cell growth by activating the STAT3-COX-2 signaling pathway

PubMed Central

Zhen, Yulan; Wu, Qiaomei; Ding, Yiqian; Zhang, Wei; Zhai, Yuansheng; Lin, Xiaoxiong; Weng, Yunxia; Guo, Ruixian; Zhang, Ying; Feng, Jianqiang; Lei, Yiyan; Chen, Jingfu

2018-01-01

The effects of hydrogen sulfide (H2S) on cancer are controversial. Our group previously demonstrated that exogenous H2S promotes the development of cancer via amplifying the activation of the nuclear factor-κB signaling pathway in hepatocellular carcinoma (HCC) cells (PLC/PRF/5). The present study aimed to further investigate the hypothesis that exogenous H2S promotes PLC/PRF/5 cell proliferation and migration, and inhibits apoptosis by activating the signal transducer and activator of transcription 3 (STAT3)-cyclooxygenase-2 (COX-2) signaling pathway. PLC/PRF/5 cells were treated with 500 µmol/l NaHS (a donor of H2S) for 24 h. The expression levels of phosphorylated (p)-STAT3, STAT3, cleaved caspase-3 and COX-2 were measured by western blot assay. Cell viability was detected by Cell Counting kit-8 assay. Apoptotic cells were observed by Hoechst 33258 staining. The expression of STAT3 and COX-2 messenger RNA (mRNA) was detected by semiquantitative reverse transcription-polymerase chain reaction. The production of vascular endothelial growth factor (VEGF) was evaluated by ELISA. The results indicated that treatment of PLC/PRF/5 cells with 500 µmol/l NaHS for 24 h markedly increased the expression levels of p-STAT3 and STAT3 mRNA, leading to COX-2 and COX-2 mRNA overexpression, VEGF induction, decreased cleaved caspase-3 production, increased cell viability and migration, and decreased number of apoptotic cells. However, co-treatment of PLC/PRF/5 cells with 500 µmol/l NaHS and 30 µmol/l AG490 (an inhibitor of STAT3) or 20 µmol/l NS-398 (an inhibitor of COX-2) for 24 h significantly reverted the effects induced by NaHS. Furthermore, co-treatment of PLC/PRF/5 cells with 500 µmol/l NaHS and 30 µmol/l AG490 markedly decreased the NaHS-induced increase in the expression level of COX-2. By contrast, co-treatment of PLC/PRF/5 cells with 500 µmol/l NaHS and 20 µmol/l NS-398 inhibited the NaHS-induced increase in the expression level of p-STAT3. In conclusion, the findings of the present study provide evidence that the STAT3-COX-2 signaling pathway is involved in NaHS-induced cell proliferation, migration, angiogenesis and anti-apoptosis in PLC/PRF/5 cells, and suggest that the positive feedback between STAT3 and COX-2 may serve a crucial role in hepatocellular carcinoma carcinogenesis. PMID:29725404

Eupafolin inhibits PGE2 production and COX2 expression in LPS-stimulated human dermal fibroblasts by blocking JNK/AP-1 and Nox2/p47{sup phox} pathway

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tsai, Ming-Horng; Lin, Zih-Chan; Liang, Chan-Jung

2014-09-01

Eupafolin, a major active component found in the methanol extracts of Phyla nodiflora, has been used to treat inflammation of skin. We examined its effects on cyclooxygenase-2 (COX-2) expression in LPS-treated human dermal fibroblasts. Lipopolysaccharide (LPS) significantly increased prostaglandin-E2 (PGE2) production associated with increased COX-2 expression in Hs68 cells. This effect was blocked by eupafolin, TLR-4 antibody, antioxidants (APO and NAC), as well as inhibitors, including U0126 (ERK1/2), SB202190 (p38), SP600125 (JNK1/2), and Tanshinone IIA (AP-1). In gene regulation level, qPCR and promoter assays revealed that COX-2 expression was attenuated by eupafolin. In addition, eupafolin also ameliorated LPS-induced p47 phoxmore » activation and decreased reactive oxygen species (ROS) generation and NADPH oxidase (Nox) activity. Moreover, pretreatment with eupafolin and APO led to reduced LPS-induced phosphorylation of ERK1/2, JNK, and p38. Further, eupafolin attenuated LPS-induced increase in AP-1 transcription factor binding activity as well as the increase in the phosphorylation of c-Jun and c-Fos. In vivo studies have shown that in dermal fibroblasts of LPS treated mice, eupafolin exerted anti-inflammation effects by decreasing COX-2 protein levels. Our results reveal a novel mechanism for anti-inflammatory and anti-oxidative effects of eupafolin that involved inhibition of LPS-induced ROS generation, suppression of MAPK phosphorylation, diminished DNA binding activity of AP-1 and attenuated COX-2 expression leading to reduced production of prostaglandin E2 (PGE2). Our results demonstrate that eupafolin may be used to treat inflammatory responses associated with dermatologic diseases. - Highlights: • LPS activates the Nox2/p47{sup phox}/JNK/AP-1 and induces COX2 expression in Hs68 cells. • Eupafolin inhibits LPS-induced COX-2 expression via Nox2/p47{sup phox} inhibition. • Eupafolin may be used in the treatment of skin diseases involving inflammation.« less

Soman increases neuronal COX-2 levels: possible link between seizures and protracted neuronal damage.

PubMed

Angoa-Pérez, Mariana; Kreipke, Christian W; Thomas, David M; Van Shura, Kerry E; Lyman, Megan; McDonough, John H; Kuhn, Donald M

2010-12-01

Nerve agent-induced seizures cause neuronal damage in brain limbic and cortical circuits leading to persistent behavioral and cognitive deficits. Without aggressive anticholinergic and benzodiazepine therapy, seizures can be prolonged and neuronal damage progresses for extended periods of time. The objective of this study was to determine the effects of the nerve agent soman on expression of cyclooxygenase-2 (COX-2), the initial enzyme in the biosynthetic pathway of the proinflammatory prostaglandins and a factor that has been implicated in seizure initiation and propagation. Rats were exposed to a toxic dose of soman and scored behaviorally for seizure intensity. Expression of COX-2 was determined throughout brain from 4h to 7 days after exposure by immunohistochemistry and immunoblotting. Microglial activation and astrogliosis were assessed microscopically over the same time-course. Soman increased COX-2 expression in brain regions known to be damaged by nerve agents (e.g., hippocampus, amygdala, piriform cortex and thalamus). COX-2 expression was induced in neurons, and not in microglia or astrocytes, and remained elevated through 7 days. The magnitude of COX-2 induction was correlated with seizure intensity. COX-1 expression was not changed by soman. Increased expression of neuronal COX-2 by soman is a late-developing response relative to other signs of acute physiological distress caused by nerve agents. COX-2-mediated production of prostaglandins is a consequence of the seizure-induced neuronal damage, even after survival of the initial cholinergic crisis is assured. COX-2 inhibitors should be considered as adjunct therapy in nerve agent poisoning to minimize nerve agent-induced seizure activity. Published by Elsevier B.V.

Autocrine prostaglandin E2 signaling promotes promonocytic leukemia cell survival via COX-2 expression and MAPK pathway

PubMed Central

Lee, Jaetae; Lee, Young Sup

2015-01-01

The COX-2/PGE2 pathway has been implicated in the occurrence and progression of cancer. The underlying mechanisms facilitating the production of COX-2 and its mediator, PGE2, in cancer survival remain unknown. Herein, we investigated PGE2-induced COX-2 expression and signaling in HL-60 cells following menadione treatment. Treatment with PGE2 activated anti-apoptotic proteins such as Bcl-2 and Bcl-xL while reducing pro-apoptotic proteins, thereby enhancing cell survival. PGE2 not only induced COX-2 expression, but also prevented casapse-3, PARP, and lamin B cleavage. Silencing and inhibition of COX-2 with siRNA transfection or treatment with indomethacin led to a pronounced reduction of the extracellular levels of PGE2, and restored the menadione-induced cell death. In addition, pretreatment of cells with the MEK inhibitor PD98059 and the PKA inhibitor H89 abrogated the PGE2-induced expression of COX-2, suggesting involvement of the MAPK and PKA pathways. These results demonstrate that PGE2 signaling acts in an autocrine manner, and specific inhibition of PGE2 will provide a novel approach for the treatment of leukemia. [BMB Reports 2015; 48(2): 109-114] PMID:24965577

Endothelin-1 increases expression of cyclooxygenase-2 and production of interlukin-8 in hunan pulmonary epithelial cells.

PubMed

Peng, Hong; Chen, Ping; Cai, Ying; Chen, Yan; Wu, Qing-Hua; Li, Yun; Zhou, Rui; Fang, Xiang

2008-03-01

Inducible cyclooxygenase (COX-2) and inflammatory cytokines play important roles in inflammatory processes of chronic obstructive pulmonary disease (COPD). Endothelin-1 (ET-1) might be also involved in the pathophysilogical processes in COPD. In the present study, we determined whether ET-1 could regulate the expression of COX-2 and alter the production of interleukin-8 (IL-8) in human pulmonary epithelial cells (A549). Induced sputum samples were collected from 13 stable COPD patients and 14 healthy subjects. The COX-2 protein, ET-1, PGE(2) and IL-8 in these sputum samples were analyzed. A549 cells were incubated with ET-1 in the presence or absence of celecoxib, a selective COX-2 inhibitor. The expression of COX-2 protein in the cell and the amounts of PGE(2) and IL-8 in the medium were measured. The levels of COX-2 protein, ET-1, PGE(2) and IL-8 were significantly increased in induced sputum from COPD patients when compared to healthy subjects. ET-1 increased the expression of COX-2 protein, as well as the production of PGE(2) in A549 cells. Increased production of PGE(2) was inhibited by celecoxib. ET-1 also increased the production of IL-8. Interestingly, ET-1-induced production of IL-8 was also inhibited by celecoxib. These findings indicate that ET-1 plays important roles in regulating COX-2 expression and production of IL-8 in A549 cells. ET-1 mediated production of IL-8 is likely through a COX-2-dependent mechanism.

COX-2/PGE2: molecular ambassadors of Kaposi's sarcoma-associated herpes virus oncoprotein-v-FLIP

PubMed Central

Sharma-Walia, N; Patel, K; Chandran, K; Marginean, A; Bottero, V; Kerur, N; Paul, A G

2012-01-01

Kaposi's sarcoma herpesvirus (KSHV) latent oncoprotein viral FLICE (FADD-like interferon converting enzyme)-like inhibitory protein (v-FLIP) or K13, a potent activator of NF-κB, has well-established roles in KSHV latency and oncogenesis. KSHV-induced COX-2 represents a novel strategy employed by KSHV to promote latency and inflammation/angiogenesis/invasion. Here, we demonstrate that v-FLIP/K13 promotes tumorigenic effects via the induction of host protein COX-2 and its inflammatory metabolite PGE2 in an NF-κB-dependent manner. In addition to our previous studies demonstrating COX-2/PGE2's role in transcriptional regulation of KSHV latency promoter and latent gene expression, the current study adds to the complexity that though LANA-1 (latency associated nuclear antigen) is utilizing COX-2/PGE2 as critical factors for its transcriptional regulation, it is the v-FLIP/K13 gene in the KSHV latency cluster that maintains continuous COX-2/PGE2 levels in the infected cells. We demonstrate that COX-2 inhibition, via its chemical inhibitors (NS-398 or celecoxib), reduced v-FLIP/K13-mediated NF-κB induction, and extracellular matrix (ECM) interaction-mediated signaling, mitochondrial antioxidant enzyme manganese superoxide dismutase (MnSOD) levels, and subsequently downregulated detachment-induced apoptosis (anoikis) resistance. vFLIP expression mediated the secretion of cytokines, and spindle cell differentiation activated the phosphorylation of p38, RSK, FAK, Src, Akt and Rac1-GTPase. The COX-2 inhibition in v-FLIP/K13-HMVECs reduced inflammation and invasion/metastasis-related genes, along with reduced anchorage-independent colony formation via modulating ‘extrinsic' as well as ‘intrinsic' cell death pathways. COX-2 blockade in v-FLIP/K13-HMVEC cells drastically augmented cell death induced by removal of essential growth/survival factors secreted in the microenvironment. Transformed cells obtained from anchorage-independent colonies of COX-2 inhibitor-treated v-FLIP/K13-HMVEC cells expressed lower levels of endothelial–mesenchymal transition genes such as slug, snail and twist, and higher expression of the tumor-suppressor gene, E-cadherin. Taken together, our study provides strong evidences that FDA-approved COX-2 inhibitors have great potential in blocking tumorigenic events linked to KSHV's oncogenic protein v-FLIP/K13. PMID:23552603

Induction of cyclooxygenase-2 expression by allergens in lymphocytes from allergic patients.

PubMed

Chacón, Pedro; Vega, Antonio; Monteseirín, Javier; El Bekay, Rajaa; Alba, Gonzalo; Pérez-Formoso, José Luis; Msartínez, Alberto; Asturias, Juan A; Pérez-Cano, Ramón; Sobrino, Francisco; Conde, José

2005-08-01

Cyclooxygenase (COX) is a key enzyme in prostaglandin (PG) synthesis. Up-regulation of COX-2 expression is responsible for increased PG release during inflammatory conditions and is thought to be also involved in allergic states. In this study, we demonstrate that in human T, B and natural killer lymphocytes from allergic patients, COX-2 expression became induced upon cell challenge with specific allergens and that this process is presumably IgE dependent and occurs after CD23 receptor ligation. This induction took place at both mRNA and protein levels and was accompanied by PGD2 release. IgE-dependent lymphocyte treatment elicited, in parallel, an activation of the MAPK p38 and extracellular signal-regulated kinase 1/2, an enhancement of calcineurin (CaN) activity, and an increase of the DNA-binding activity of the nuclear factor of activated T cells and of NF-kappaB, with a concomitant decrease in the levels of the cytosolic inhibitor of kappaB, IkappaB. In addition, specific chemical inhibitors of MAPK, such as PD098059 and SB203580, as well as MG-132, an inhibitor of proteasomal activity, abolished allergen-induced COX-2 up-regulation, suggesting that this process is mediated by MAPK and NF-kappaB. However, induction of COX-2 expression was not hampered by the CaN inhibitor cyclosporin A. We also examined the effect of a selective COX-2 inhibitor, NS-398, on cytokine production by human lymphocytes. Treatment with NS-398 severely diminished the IgE-dependently induced production of IL-8 and TNF-alpha. These results underscore the relevant role of lymphocyte COX-2 in allergy and suggest that COX-2 inhibitors may contribute to the improvement of allergic inflammation through the reduction of inflammatory mediator production by human lymphocytes.

Kupffer cell ablation attenuates cyclooxygenase-2 expression after trauma and sepsis.

PubMed

Keller, Steve A; Paxian, Marcus; Lee, Sun M; Clemens, Mark G; Huynh, Toan

2005-03-01

Prostaglandins, synthesized by cyclooxygenase (COX), play an important role in the pathophysiology of inflammation. Severe injuries result in immunosuppression, mediated, in part, by maladaptive changes in macrophages. Herein, we assessed Kupffer cell-mediated cyclooxygenase-2 (COX-2) expression on liver function and damage after trauma and sepsis. To ablate Kupffer cells, Sprague Dawley rats were treated with gadolinium chloride (GdCl3) 48 and 24 h before experimentation. Animals then underwent femur fracture (FFx) followed 48 h later by cecal ligation and puncture (CLP). Controls received sham operations. After 24 h, liver samples were obtained, and mRNA and protein expression were determined by PCR, Western blot, and immunohistochemistry. Indocyanine-Green (ICG) clearance and plasma alanine aminotransferase (ALT) levels were determined to assess liver function and damage, respectively. One-way analysis of variance (ANOVA) with Student-Newman-Keuls test was used to assess statistical significance. After CLP alone, FFx+CLP, and GdCl3+FFx+CLP, clearance of ICG decreased. Plasma ALT levels increased in parallel with severity of injury. Kupffer cell depletion attenuated the increased ALT levels after FFx+CLP. Femur fracture alone did not alter COX-2 protein compared with sham. By contrast, COX-2 protein increased after CLP and was potentiated by sequential stress. Again, Kupffer cell depletion abrogated the increase in COX-2 after sequential stress. Immunohistochemical data confirmed COX-2 positive cells to be Kupffer cells. In this study, sequential stress increased hepatic COX-2 protein. Depletion of Kupffer cells reduced COX-2 and attenuated hepatocellular injuries. Our data suggest that Kupffer cell-dependent pathways may contribute to the inflammatory response leading to increased mortality after sequential stress.

Expression of cyclooxygenase-2 in the canine lower urinary tract with regard to the effects of gonadal status and gender.

PubMed

Ponglowhapan, S; Church, D B; Khalid, M

2009-05-01

As pituitary gonadotrophins can induce prostaglandin (PG) synthesis and receptors for LH and FSH are present in the canine lower urinary tract (LUT), the objectives of this study were to (i) investigate the expression of COX-2, a key rate-limiting enzyme in PG production, in the canine LUT and (ii) determine if COX-2 expression differs between gender, gonadal status (intact and gonadectomised) and LUT regions. Four regions (body and neck of the bladder as well as proximal and distal urethra) of the LUT were obtained from 20 clinically healthy dogs (5 intact males, 5 intact anoestrous females, 4 castrated males, 6 spayed females). In situ hybridization and immunohistochemistry were performed to determine the presence of COX-2 mRNA and protein, respectively. The mRNA and protein expression was semi-quantitatively assessed. The scoring system combined both the distribution and intensity of positive staining and was carried out separately on the three tissue layers (epithelium, sub-epithelial stroma and muscle) for each of four regions of the LUT. In comparison to intact dogs, lower expression (P<0.001) of COX-2 and its mRNA in gonadectomised males and females was observed in all tissue layers of each region of the LUT except in the distal urethra where there was no difference in mRNA expression between gonadal statuses. Regardless of region and tissue layer, intact females expressed more (P<0.05) COX-2 and its mRNA than intact males. However, in gonadectomised dogs, mRNA expression of COX-2 did not differ between genders; males had higher (P<0.001) protein level of COX-2 compared to females. In conclusion, both COX-2 and its mRNA were expressed in the canine LUT and COX-2-regulated PG synthesis in the canine LUT may differ between gonadal statuses and genders. The lower expression of COX-2 in gonadectomised dogs may impair normal function of the LUT and probably implicated in the development of neutering-induced urinary incontinence in the dog.

Carrageenan-induced mouse paw oedema is biphasic, age-weight dependent and displays differential nitric oxide cyclooxygenase-2 expression

PubMed Central

Posadas, Inmaculada; Bucci, Mariarosaria; Roviezzo, Fiorentina; Rossi, Antonietta; Parente, Luca; Sautebin, Lidia; Cirino, Giuseppe

2004-01-01

Injection of carrageenan 1% (50 μl) in the mouse paw causes a biphasic response: an early inflammatory response that lasts 6 h and a second late response that peaks at 72 h, declining at 96 h. Only mice 7- or 8-week old, weighing 32–34 g, displayed a consistent response in both phases. In 8-week-old mice, myeloperoxidase (MPO) levels are significantly elevated in the early phase at 6 h and reach their maximum at 24 h to decline to basal value at 48 h. Nitrate+nitrite (NOx) levels in the paw are maximal after 2 h and slowly decline thereafter in contrast to prostaglandin E2 levels that peak in the second phase at the 72 h point. Western blot analysis showed that inducible nitric oxide synthase (iNOS) is detectable at 6 h and cyclooxygenase 2 (COX-2) at 24 h point, respectively. Analysis of endothelial nitric oxide synthase (eNOS), iNOS and COX-2 expression at 6 and 24 h in 3–8-week-old mice demonstrated that both eNOS and iNOS expressions are dependent upon the age–weight of mice, as opposite to COX-2 that is present only in the second phase of the oedema and is not linked to mouse age–weight. Subplantar injection of carrageenan to C57BL/6J causes a biphasic oedema that is significantly reduced by about 20% when compared to CD1 mice. Interestingly, in these mice, iNOS expression is absent up to 6 h, as opposite to CD1, and becomes detectable at the 24 h point. Cyclooxygenase (COX-1) expression is upregulated between 4 and 24 h after carrageenan injection, whereas in CD1 mice COX-1 remains unchanged after irritant agent injection. MPO levels are maximal at the 24 h point and they are significantly lower, at 6 h point, than MPO levels detected in CD1 mice. In conclusion, mouse paw oedema is biphasic and age-weight dependent. The present results are the first report on the differential expressions of eNOS, iNOS, COX-1 and COX-2 in response to carrageenan injection in the two phases of the mouse paw oedema. PMID:15155540

Platelet cyclooxygenase expression in normal dogs.

PubMed

Thomason, J; Lunsford, K; Mullins, K; Stokes, J; Pinchuk, L; Wills, R; McLaughlin, R; Langston, C; Pruett, S; Mackin, A

2011-01-01

Human platelets express both cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2). Variation in COX-2 expression could be a mechanism for variable response to aspirin. The hypotheses were that circulating canine platelets express COX-1 and COX-2, and that aspirin alters COX expression. The objective was to identify changes in platelet COX expression and in platelet function caused by aspirin administration to dogs. Eight female, intact hounds. A single population, repeated measures design was used to evaluate platelet COX-1 and COX-2 expression by flow cytometry before and after aspirin (10 mg/kg Q12h for 10 days). Platelet function was analyzed via PFA-100(®) (collagen/epinephrine), and urine 11-dehydro-thromboxane B(2) (11-dTXB(2)) was measured and normalized to urinary creatinine. Differences in COX expression, PFA-100(®) closure times, and urine 11-dTXB(2 ): creatinine ratio were analyzed before and after aspirin administration. Both COX-1 and COX-2 were expressed in canine platelets. COX-1 mean fluorescent intensity (MFI) increased in all dogs, by 250% (range 63-476%), while COX-2 expression did not change significantly (P = 0.124) after aspirin exposure, with large interindividual variation. PFA-100(®) closure times were prolonged and urine 11-dTXB(2) concentration decreased in all dogs after aspirin administration. Canine platelets express both COX isoforms. After aspirin exposure, COX-1 expression increased despite impairment of platelet function, while COX-2 expression varied markedly among dogs. Variability in platelet COX-2 expression should be explored as a potential mechanism for, or marker of, variable aspirin responsiveness. Copyright © 2011 by the American College of Veterinary Internal Medicine.

Muramyl dipeptide (MDP) induces reactive oxygen species (ROS) generation via the NOD2/COX-2/NOX4 signaling pathway in human umbilical vein endothelial cells (HUVECs).

PubMed

Kong, Ling-Jun; Liu, Xiao-Qian; Xue, Ying; Gao, Wei; Lv, Qian-Zhou

2018-03-20

Vascular endothelium dysfunction caused by oxidative stress accelerates the pathologic process of cardiovascular diseases. NOD2, an essential receptor of innate immune system, has been demonstrated to play a critical role in atherosclerosis. Here, the aim of our study was to investigate the effect and underlying molecular mechanism of muramyl dipeptide (MDP) on NOX4-mediated ROS generation in human umbilical vein endothelial cells (HUVECs). 2,7-dichlorofluorescein diacetate staining was to measure the intracellular ROS level and showed MDP promoted ROS production in a time- and dose-dependent manner. The mRNA and protein levels of NOX4 and COX-2 were detected by real-time PCR and western blot. Small interfering RNA (siRNA) was used to silence NOD2 or COX-2 gene expression and investigate the mechanism of NOD2-mediated signaling pathway in HUVECs. Data showed that MDP induced NOX4 and COX-2 expression in a time- and dose-dependent manner. NOD2 knock-down suppressed up-regulation of COX-2 and NOX4 in HUVECs treated with MDP. Furthermore, silence of COX-2 in HUVECs down-regulated the NOX4 expression after MDP stimulation. Collectively, we indicated that NOD2 played a leading role in MDP-induced COX-2/NOX4/ROS signaling pathway in HUVECs, which was a novel regulatory mechanism in the progress of ROS generation.

Influenza A viruses suppress cyclooxygenase-2 expression by affecting its mRNA stability.

PubMed

Dudek, Sabine Eva; Nitzsche, Katja; Ludwig, Stephan; Ehrhardt, Christina

2016-06-06

Infection with influenza A viruses (IAV) provokes activation of cellular defence mechanisms contributing to the innate immune and inflammatory response. In this process the cyclooxygenase-2 (COX-2) plays an important role in the induction of prostaglandin-dependent inflammation. While it has been reported that COX-2 is induced upon IAV infection, in the present study we observed a down-regulation at later stages of infection suggesting a tight regulation of COX-2 by IAV. Our data indicate the pattern-recognition receptor RIG-I as mediator of the initial IAV-induced COX-2 synthesis. Nonetheless, during on-going IAV replication substantial suppression of COX-2 mRNA and protein synthesis could be detected, accompanied by a decrease in mRNA half-life. Interestingly, COX-2 mRNA stability was not only imbalanced by IAV replication but also by stimulation of cells with viral RNA. Our results reveal tristetraprolin (TTP), which is known to bind COX-2 mRNA and promote its rapid degradation, as regulator of COX-2 expression in IAV infection. During IAV replication and viral RNA accumulation TTP mRNA synthesis was induced, resulting in reduced COX-2 levels. Accordingly, the down-regulation of TTP resulted in increased COX-2 protein expression after IAV infection. These findings indicate a novel IAV-regulated cellular mechanism, contributing to the repression of host defence and therefore facilitating viral replication.

Effects of electroacupuncture on luteal regression and steroidogenesis in ovarian hyperstimulation syndrome model rat.

PubMed

Huang, Xuan; Chen, Li; Xia, You-Bing; Xie, Min; Sun, Qin; Yao, Bing

2018-03-15

Electroacupuncture (EA) is an effective and safe therapeutic method widely used for treating clinical diseases. Previously, we found that EA could decrease serum hormones and reduce ovarian size in ovarian hyperstimulation syndrome (OHSS) rat model. Nevertheless, the mechanisms that contribute to these improvements remain unclear. HE staining was used to count the number of corpora lutea (CL) and follicles. Immunohistochemical and ELISA were applied to examine luteal functional and structural regression. Immunoprecipitation was used for analyzing the interaction between NPY (neuropeptide Y) and COX-2; western blotting and qRT-PCR were used to evaluate the expressions of steroidogenic enzymes and PKA/CREB pathway. EA treatment significantly reduced the ovarian weight and the number of CL, also decreased ovarian and serum levels of PGE2 and COX-2 expression; increased ovarian PGF2α levels and PGF2α/PGE2 ratio; decreased PCNA expression and distribution; and increased cyclin regulatory inhibitor p27 expression to have further effect on the luteal formation, and promote luteal functional and structural regression. Moreover, expression of COX-2 in ovaries was possessed interactivity increased expression of NPY. Furthermore, EA treatment lowered the serum hormone levels, inhibited PKA/CREB pathway and decreased the expressions of steroidogenic enzymes. Hence, interaction with COX-2, NPY may affect the levels of PGF2α and PGE2 as well as impact the proliferation of granulosa cells in ovaries, thus further reducing the luteal formation, and promoting luteal structural and functional regression, as well as the ovarian steroidogenesis following EA treatment. EA treatment could be an option for preventing OHSS in ART. Copyright © 2018 Elsevier Inc. All rights reserved.

Targeting Estrogen-Induced COX-2 Activity in Lymphangioleiomyomatosis (LAM)

DTIC Science & Technology

2014-12-01

production was also increased in TSC2-deficient cells. In preclinical models, both Celecoxib and aspirin reduced tumor development. LAM patients had...increased by aspirin treatment, indicative of functional COX-2 expression in the LAM airway. In vitro, 15-epi-lipoxin-A4 reduced the proliferation of...inhibit COX-2 pharmacologically, we treated TSC2-deficient cells with aspirin or NS398, and found that both agents reduced COX-2 protein levels and

COX-2/EGFR expression and survival among women with adenocarcinoma of the lung

PubMed Central

Van Dyke, Alison L.; Cote, Michele L.; Prysak, Geoffrey M.; Claeys, Gina B.; Wenzlaff, Angie S.; Murphy, Valerie C.; Lonardo, Fulvio; Schwartz, Ann G.

2008-01-01

Previous studies suggest that cyclooxygenase-2 (COX-2) expression may predict survival among patients with non-small cell lung cancer. COX-2 may interact with epidermal growth factor receptor (EGFR), suggesting that combined COX-2/EGFR expression may provide predictive value. The extent to which their independent or combined expression is associated with prognosis in women with adenocarcinoma of the lung is unknown. In the present study, we examined relationships between COX-2 expression (n = 238), EGFR expression (n = 158) and dual COX-2/EGFR expression (n = 157) and survival among women with adenocarcinoma of the lung. Overall survival was estimated by constructing Cox proportional hazards models adjusting for other significant variables and stratifying by stage at diagnosis and race. Clinical or demographic parameters were not associated with either COX-2 or EGFR expression. Patients with COX-2-positive tumors tended to have poorer prognosis than did patients with COX-2-negative tumors [hazard ratio (HR) 1.67, 95% confidence interval (CI) 1.01–2.78]. African-Americans with COX-2-positive tumors had a statistically non-significant higher risk of death than African-Americans with COX-2-negative tumors (HR 5.58, 95% CI 0.64–48.37). No association between COX-2 expression and survival was observed among Caucasians (HR 1.29, 95% CI 0.72–2.30). EGFR expression was associated with a 44% reduction in the risk of death (HR 0.56, 95% CI 0.32–0.98). COX-2−/EGFR+ tumor expression, but not COX-2+/EGFR+ tumor expression, was associated with survival when compared with other combined expression results. In conclusion, COX-2 and EGFR expression, but not combined COX-2+/EGFR+ expression, independently predict survival of women with adenocarcinoma of the lung. PMID:18453539

Norepinephrine enhances the LPS-induced expression of COX-2 and secretion of PGE2 in primary rat microglia

PubMed Central

2010-01-01

Background Recent studies suggest an important role for neurotransmitters as modulators of inflammation. Neuroinflammatory mediators such as cytokines and molecules of the arachidonic acid pathway are generated and released by microglia. The monoamine norepinephrine reduces the production of cytokines by activated microglia in vitro. However, little is known about the effects of norepinephrine on prostanoid synthesis. In the present study, we investigate the role of norepinephrine on cyclooxygenase- (COX-)2 expression/synthesis and prostaglandin (PG)E2 production in rat primary microglia. Results Interestingly, norepinephrine increased COX-2 mRNA, but not protein expression. Norepinephrine strongly enhanced COX-2 expression and PGE2 production induced by lipopolysaccharide (LPS). This effect is likely to be mediated by β-adrenoreceptors, since β-, but not α-adrenoreceptor agonists produced similar results. Furthermore, β-adrenoreceptor antagonists blocked the enhancement of COX-2 levels induced by norepinephrine and β-adrenoreceptor agonists. Conclusions Considering that PGE2 displays different roles in neuroinflammatory and neurodegenerative disorders, norepinephrine may play an important function in the modulation of these processes in pathophysiological conditions. PMID:20064241

Modulation of IgE-dependent COX-2 gene expression by reactive oxygen species in human neutrophils.

PubMed

Vega, Antonio; Chacón, Pedro; Alba, Gonzalo; El Bekay, Rajaa; Martín-Nieto, José; Sobrino, Francisco

2006-07-01

Cyclooxygenase (COX) is a key enzyme in prostaglandin (PG) synthesis. Up-regulation of its COX-2 isoform is responsible for the increased PG release, taking place under inflammatory conditions, and also, is thought to be involved in allergic and inflammatory diseases. In the present work, we demonstrate that COX-2 expression becomes highly induced by anti-immunoglobulin E (IgE) antibodies and by antigens in human neutrophils from allergic patients. This induction was detected at mRNA and protein levels and was accompanied by a concomitant PGE(2) and thromboxane A(2) release. We also show evidence that inhibitors of reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, such as 4-(2-aminoethyl)benzenesulphonyl fluoride and 4-hydroxy-3-methoxyaceto-phenone, completely cancelled anti-IgE-induced COX-2 protein up-regulation, suggesting that this process is mediated by reactive oxygen species (ROS) derived from NADPH oxidase activity. Moreover, the mitogen-activated protein kinases (MAPKs), p38 and extracellular signal-regulated kinase, and also, the transcription factor, nuclear factor (NF)-kappaB, are involved in the up-regulation of COX-2 expression, as specific chemical inhibitors of these two kinases, such as SB203580 and PD098059, and of the NF-kappaB pathway, such as N(alpha)-benzyloxycarbonyl-l-leucyl-l-leucyl-l-leucinal, abolished IgE-dependent COX-2 induction. Evidence is also presented, using Fe(2)(+)/Cu(2)(+) ions, that hydroxyl radicals generated from hydrogen peroxide through Fenton reactions could constitute candidate modulators able to directly trigger anti-IgE-elicited COX-2 expression through MAPK and NF-kappaB pathways. Present results underscore a new role for ROS as second messengers in the modulation of COX-2 expression by human neutrophils in allergic conditions.

Modulation of the neurological and vascular complications by grape seed extract in a rat model of spinal cord ischemia-reperfusion injury by downregulation of both osteopontin and cyclooxygenase-2.

PubMed

Sakr, Hussein F; Abbas, Amr M; Bin-Jaliah, Ismaeel

2016-07-01

In this study, we investigated the effects of grape seed extract (GSE) on the expression of osteopontin (OPN) and cyclooxygenase-2 (COX-2) in a rat model of spinal cord ischemia-reperfusion injury (SC-IRI). Fifty male rats were divided into 5 groups: control (CON); control + GSE (CON + GSE) (received GSE for 28 days); sham operated (Sham); IRI; and IRI + GSE. SC-IRI was induced by clamping the aorta just above the bifurcation for 45 min, and then the clamp was released for 48 h for reperfusion. IRI + GSE group received GSE for 28 days before SC-IRI. Sensory, motor, and placing/stepping reflex assessment was performed. Prostaglandin E2 (PGE2), thiobarbituric acid reactive substances (TBARs), and total antioxidant capacity (TAC) were measured in spinal cord homogenate. Immunohistochemical examination of the spinal cord for OPN and COX-2 were carried out. SC-IRI resulted in significant increase in plasma nitrite/nitrate level and spinal cord homogenate levels of TBARs and PGE2, and OPN and COX-2 expression with significant decrease in TAC. GSE improves the sensory and motor functions through decreasing OPN and COX-2 expression with reduction of oxidative stress parameters. We conclude a neuroprotective effect of GSE in SC-IRI through downregulating COX-2 and OPN expression plus its antioxidants effects.

Lactobacillus fermentum ZYL0401 Attenuates Lipopolysaccharide-Induced Hepatic TNF-α Expression and Liver Injury via an IL-10- and PGE2-EP4-Dependent Mechanism

PubMed Central

Lv, Longxian; Yang, Jianzhuan; Lu, Haifeng; Li, Lanjuan

2015-01-01

Lipopolysaccharide (LPS) has essential role in the pathogenesis of D-galactosamine-sensitized animal models and alcoholic liver diseases of humans, by stimulating release of pro-inflammatory mediators that cause hepatic damage and intestinal barrier impairment. Oral pretreatment of probiotics has been shown to attenuate LPS-induced hepatic injury, but it is unclear whether the effect is direct or due to improvement in the intestinal barrier. The present study tested the hypothesis that pretreatment with probiotics enables the liver to withstand directly LPS-induced hepatic injury and inflammation. In a mouse model of LPS-induced hepatic injury, the levels of hepatic tumor necrosis factor-alpha (TNF-α) and serum alanine aminotransferase (ALT) of mice with depleted intestinal commensal bacteria were not significantly different from that of the control models. Pre-feeding mice for 10 days with Lactobacillus fermentum ZYL0401 (LF41), significantly alleviated LPS-induced hepatic TNF-α expression and liver damage. After LF41 pretreatment, mice had dramatically more L.fermentum-specific DNA in the ileum, significantly higher levels of ileal cyclooxygenase (COX)-2 and interleukin 10 (IL-10) and hepatic prostaglandin E2 (PGE2). However, hepatic COX-1, COX-2, and IL-10 protein levels were not changed after the pretreatment. There were also higher hepatic IL-10 protein levels after LPS challenge in LF41-pretreaed mice than in the control mice. Attenuation of hepatic TNF-α was mediated via the PGE2/E prostanoid 4 (EP4) pathway, and serum ALT levels were attenuated in an IL-10-dependent manner. A COX-2 blockade abolished the increase in hepatic PGE2 and IL-10 associated with LF41. In LF41-pretreated mice, a blockade of IL-10 caused COX-2-dependent promotion of hepatic PGE2, without affecting hepatic COX-2levels. In LF41-pretreated mice, COX2 prevented enhancing TNF-α expression in both hepatic mononuclear cells and the ileum, and averted TNF-α-mediated increase in intestinal permeability. Together, we demonstrated that LF41 pre-feeding enabled the liver to alleviate LPS-induced hepatic TNF-α expression and injury via a PGE2-EP4- and IL-10-dependent mechanism. PMID:25978374

Endoplasmic reticulum stress (ER-stress) by 2-deoxy-D-glucose (2DG) reduces cyclooxygenase-2 (COX-2) expression and N-glycosylation and induces a loss of COX-2 activity via a Src kinase-dependent pathway in rabbit articular chondrocytes.

PubMed

Yu, Seon-Mi; Kim, Song-Ja

2010-11-30

Endoplasmic reticulum (ER) stress regulates a wide range of cellular responses including apoptosis, proliferation, inflammation, and differentiation in mammalian cells. In this study, we observed the role of 2-deoxy-D-glucose (2DG) on inflammation of chondrocytes. 2DG is well known as an inducer of ER stress, via inhibition of glycolysis and glycosylation. Treatment of 2DG in chondrocytes considerably induced ER stress in a dose- and time-dependent manner, which was demonstrated by a reduction of glucose regulated protein of 94 kDa (grp94), an ER stress-inducible protein, as determined by a Western blot analysis. In addition, induction of ER stress by 2DG led to the expression of COX-2 protein with an apparent molecular mass of 66-70kDa as compared with the normally expressed 72-74 kDa protein. The suppression of ER stress with salubrinal (Salub), a selective inhibitor of eif2-alpha dephosphorylation, successfully prevented grp94 induction and efficiently recovered 2DG- modified COX-2 molecular mass and COX-2 activity might be associated with COX-2 N-glycosylation. Also, treatment of 2DG increased phosphorylation of Src in chondrocytes. The inhibition of the Src signaling pathway with PP2 (Src tyrosine kinase inhibitor) suppressed grp94 expression and restored COX-2 expression, N-glycosylation, and PGE2 production, as determined by a Western blot analysis and PGE2 assay. Taken together, our results indicate that the ER stress induced by 2DG results in a decrease of the transcription level, the molecular mass, and the activity of COX-2 in rabbit articular chondrocytes via a Src kinase-dependent pathway.

Expression of prostaglandin metabolising enzymes COX-2 and 15-PGDH and VDR in human granulosa cells.

PubMed

Thill, Marc; Becker, Steffi; Fischer, Dorothea; Cordes, Tim; Hornemann, Amadeus; Diedrich, Klaus; Salehin, Darius; Friedrich, Michael

2009-09-01

Prostaglandins (PGs) within the periovulatory follicle are essential for various female reproductive functions such as follicular development and maturation. In animal models, granulosa cells express the PG synthesizing enzyme cyclooxygenase-2 (COX-2) and the PG inactivating enzyme 15-hydroxyprostaglandin dehydrogenase (15-PGDH). First references suggest a correlation between vitamin D and prostaglandin metabolism through the impact of 1,25(OH)2D3 (calcitriol) on the expression of COX-2 and 15-PGDH. The expression of COX-2, 15-PGDH and the vitamin D receptor (VDR) in human granulosa cells (COV434, hGC and HGL5), which were originally isolated from different stages of follicular maturation, was determined by real-time PCR (RT-PCR) and Western blot analysis. A positive correlation of COX-2 and VDR protein was found in the COV434 and HGL5 cells and an inverse correlation of 15-PGDH and VDR protein levels in all the investigated cell types. There may be a link between VDR, associated target genes and prostaglandin metabolism in human follicular maturation and luteolysis.

miR-143 decreases COX-2 mRNA stability and expression in pancreatic cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pham, Hung; Department of Medicine, Veterans Affair Greater Los Angeles Healthcare System, Los Angeles, CA 90073; Ekaterina Rodriguez, C.

2013-09-13

Highlights: •Pancreatic cancer cells express low miR-143 levels and elevated p-MEK, p-MAPK and RREB1. •MEK inhibitors U0126 and PD98059 increase miR-143 expression. •miR-143 decreases COX-2 mRNA stability and expression and PGE{sub 2}. •miR-143 decreases p-p38MAPK, p-MEK, p-MAPK and RREB1 expression. -- Abstract: Small non-coding RNAs, microRNAs (miRNA), inhibit the translation or accelerate the degradation of message RNA (mRNA) by targeting the 3′-untranslated region (3′-UTR) in regulating growth and survival through gene suppression. Deregulated miRNA expression contributes to disease progression in several cancers types, including pancreatic cancers (PaCa). PaCa tissues and cells exhibit decreased miRNA, elevated cyclooxygenase (COX)-2 and increased prostaglandinmore » E{sub 2} (PGE{sub 2}) resulting in increased cancer growth and metastases. Human PaCa cell lines were used to demonstrate that restoration of miRNA-143 (miR-143) regulates COX-2 and inhibits cell proliferation. miR-143 were detected at fold levels of 0.41 ± 0.06 in AsPC-1, 0.20 ± 0.05 in Capan-2 and 0.10 ± 0.02 in MIA PaCa-2. miR-143 was not detected in BxPC-3, HPAF-II and Panc-1 which correlated with elevated mitogen-activated kinase (MAPK) and MAPK kinase (MEK) activation. Treatment with 10 μM of MEK inhibitor U0126 or PD98059 increased miR-143, respectively, by 187 ± 18 and 152 ± 26-fold in BxPC-3 and 182 ± 7 and 136 ± 9-fold in HPAF-II. miR-143 transfection diminished COX-2 mRNA stability at 60 min by 2.6 ± 0.3-fold in BxPC-3 and 2.5 ± 0.2-fold in HPAF-II. COX-2 expression and cellular proliferation in BxPC-3 and HPAF-II inversely correlated with increasing miR-143. PGE{sub 2} levels decreased by 39.3 ± 5.0% in BxPC-3 and 48.0 ± 3.0% in HPAF-II transfected with miR-143. Restoration of miR-143 in PaCa cells suppressed of COX-2, PGE{sub 2}, cellular proliferation and MEK/MAPK activation, implicating this pathway in regulating miR-143 expression.« less

Differential cyclooxygenase-2 expression in squamous cell carcinoma and adenocarcinoma of the uterine cervix.

PubMed

Kim, Yong Bae; Kim, Gwi Eon; Pyo, Hong Ryull; Cho, Nam Hoon; Keum, Ki Chang; Lee, Chang Geol; Seong, Jinsil; Suh, Chang Ok; Park, Tchan Kyu

2004-11-01

To determine the differential expression of cyclooxygenase-2 (COX-2) in patients with squamous cell carcinoma (SCC) and adenocarcinoma (ADC) of the uterine cervix and the prognostic significance of COX-2 expression in these histologic types. A total of 105 International Federation of Gynecology and Obstetrics Stage IIB uterine cervical cancer patients were screened for COX-2 expression immunohistochemically. COX-2 expression was determined in invasive cervical SCC (n = 84) and invasive cervical ADC (n = 21). To determine the clinical significance of COX-2 expression by histologic type, the patients were arbitrarily divided into four groups: SCC/COX-2 negative (n = 64); SCC/COX-2 positive (n = 20); ADC/COX-2 negative (n = 9); and ADC/COX-2 positive (n = 12). The clinical response to treatment, patterns of treatment failure, and survival data by COX-2 expression were compared for these two major histologic types. Univariate and multivariate analyses were performed to identify the prognostic factors influencing survival. Immunohistochemical examination showed that COX-2 expression was more frequently observed in ADC than in SCC (57% vs. 24%, p = 0.007). Moreover, COX-2 expression was an important predictor of treatment response, irrespective of the histologic type. All COX-2-negative patients achieved complete remission after initial treatment; 17% of SCC patients and 33% of ADC patients with COX-2 expression did not have complete remission after the initial treatment. The incidence of local failure for those with COX-2 expression was significantly greater than for COX-2-negative patients, regardless of histologic type. With a minimal follow-up of 60 months, the overall 5-year actuarial survival rate for SCC and ADC patients was 79% and 62%, respectively (p = 0.05). The 5-year disease-free survival rate for SCC and ADC patients was 73% and 56%, respectively (p = 0.13). Irrespective of the pathologic type, COX-2-positive patients had an unfavorable prognosis. The overall 5-year actuarial survival rate was 57% for COX-2-positive patients and 83% for COX-2-negative patients (p = 0.001). When patients were stratified into the four groups according to histologic type and COX-2 expression status, ADC/COX-2-positive patients had the worst prognosis, with an overall 5-year actuarial survival rate of 49% compared with 78% for ADC/COX-2-negative patients, 62% for SCC/COX-2-positive, and 84% for SCC/COX-2-negative patients (p = 0.007, log-rank test). Irrespective of histologic type, COX-2 expression was an independent prognostic factor by univariate and multivariate analyses. In uterine cervical cancer, COX-2 was expressed in a greater proportion of ADC patients than SCC patients. COX-2 expression was also identified as a major determiner of a poor response to treatment and of an unfavorable prognosis, irrespective of the histologic type, reflecting the importance of the COX-2 protein in the acquisition of biologic aggressiveness and more malignant phenotype or increased resistance to the standard chemotherapy and radiotherapy in both histologic types. Given these observations, we believe that that ADC/COX-2-positive patients might be appropriate candidates for future trials of selective COX-2 inhibitor adjunctive therapy.

Transgenic expression of cyclooxygenase-2 (COX2) causes premature aging phenotypes in mice.

PubMed

Kim, Joohwee; Vaish, Vivek; Feng, Mingxiao; Field, Kevin; Chatzistamou, Ioulia; Shim, Minsub

2016-10-07

Cyclooxygenase (COX) is a key enzyme in the biosynthesis of prostanoids, lipid signaling molecules that regulate various physiological processes. COX2, one of the isoforms of COX, is highly inducible in response to a wide variety of cellular and environmental stresses. Increased COX2 expression is thought to play a role in the pathogenesis of many age-related diseases. COX2 expression is also reported to be increased in the tissues of aged humans and mice, which suggests the involvement of COX2 in the aging process. However, it is not clear whether the increased COX2 expression is causal to or a result of aging. We have now addressed this question by creating an inducible COX2 transgenic mouse model. Here we show that post-natal expression of COX2 led to a panel of aging-related phenotypes. The expression of p16, p53, and phospho-H2AX was increased in the tissues of COX2 transgenic mice. Additionally, adult mouse lung fibroblasts from COX2 transgenic mice exhibited increased expression of the senescence-associated β-galactosidase. Our study reveals that the increased COX2 expression has an impact on the aging process and suggests that modulation of COX2 and its downstream signaling may be an approach for intervention of age-related disorders.

The influence of cyclooxygenase-1 expression on the efficacy of cyclooxygenase-2 inhibition in head and neck squamous cell carcinoma cell lines.

PubMed

Park, Seok-Woo; Kim, Hyo-Sun; Choi, Myung-Sun; Kim, Ji-Eun; Jeong, Woo-Jin; Heo, Dae-Seog; Sung, Myung-Whun

2011-06-01

We have previously observed that cyclooxygenase-2 (COX-2) inhibition blocked the production of vascular endothelial growth factor (VEGF) in some head and neck squamous cell carcinoma (HNSCC) cells. However, as some HNSCC cells showed little response to COX-2 inhibition, although they highly expressed COX-2 and prostaglandin E2, we set out to elucidate what made this difference between them and focused on the possibility of the differential expression of COX-1. In western blotting, we found that COX-1 was expressed in SNU-1041 and SNU-1066, but not in SNU-1076 and PCI-50. Only in those cell lines without expression of COX-1 was VEGF production blocked meaningfully by small interfering RNA of COX-2. However, by cotreating with small interfering RNAs of COX-2 and COX-1, VEGF synthesis and prostaglandin E2 were inhibited in SNU-1041 and SNU-1066, similarly in SNU-1076 and PCI-50 with high expression of only COX-2. We also found that there was no difference in the pattern of prostaglandin synthesis between COX-2 and COX-1 through enzyme-linked immunosorbent assay for various prostaglandins. Our study suggests that, as COX-1 and COX-2 express and affect VEGF synthesis in HNSCC cells, we should check COX-1 expression in investigations on cancer treatment by inhibiting COX-2-induced prostaglandins.

Netrin-1 regulates the inflammatory response of neutrophils and macrophages, and suppresses ischemic acute kidney injury by inhibiting COX-2 mediated PGE2 production

PubMed Central

Ranganathan, Punithavathi Vilapakkam; Jayakumar, Calpurnia; Mohamed, Riyaz; Dong, Zheng; Ramesh, Ganesan

2012-01-01

Netrin-1 regulates inflammation but the mechanism by which this occurs is unknown. Here we explore the role of netrin-1 in regulating the production of the prostanoid metabolite PGE2 from neutrophils in in vitro and in vivo disease models. Ischemia reperfusion in wild-type and RAG-1 knockout mice induced severe kidney injury that was associated with a large increase in neutrophil infiltration and COX-2 expression in the infiltrating leukocytes. Administration of netrin-1 suppressed COX-2 expression, PGE2 and thromboxane production, and neutrophil infiltration into the kidney. This was associated with reduced apoptosis, inflammatory cytokine and chemokine expression, and improved kidney function. Treatment with the PGE2 receptor EP4 agonist enhanced neutrophil infiltration and renal injury which was not inhibited by netrin-1. Consistent with in vivo data, both LPS and IFNγ-induced inflammatory cytokine production in macrophages and IL-17-induced IFNγ production in neutrophils were suppressed by netrin-1 in vitro by suppression of COX-2 expression. Moreover, netrin-1 regulates COX-2 expression at the transcriptional level through the regulation of NFκB activation. Thus, netrin-1 regulates the inflammatory response of neutrophils and macrophages through suppression of COX-2 mediated PGE2 production. This could be a potential drug for treating many inflammatory immune disorders. PMID:23447066

The effect of low-level diode laser on COX-2 gene expression in chronic periodontitis patients.

PubMed

Pesevska, Snezana; Gjorgoski, Icko; Ivanovski, Kiro; Soldatos, Nikolaos K; Angelov, Nikola

2017-09-01

Adjunctive treatments to scaling and root planing (SRP) such as lasers, have been utilized in the treatment of chronic periodontitis, mainly aiming to suppress and eliminate the bacteria, as well as enhancing the healing response. Eighty gingival papilla biopsy samples were obtained from 60 patients diagnosed with chronic advanced periodontitis; randomly assigned to three treatment groups (n = 20), as well as 20 subjects with no periodontal disease [group A]. Group B received SRP on a single quadrant/day for four consecutive days. On day 5, all quadrants were rescaled. Groups C and D received the same treatment as group B plus laser application with the low-level diode laser (630-670 nm, 1.875 J/cm2) for five and ten consecutive days, respectively. Papilla biopsies were obtained from subjects and evaluated by RT-PCR for expression of COX-2. The values in the control group were 0.028 0.014 and baseline values for the examined groups were 0.16 0.18. Significantly decreased level of COX-2 expression for groups C and D was found after treatment, while lowest average expression was found in the group that had the 10 laser treatments supplemental to SRP (0,035 0,014). The results of this study show suppression of COX-2 in gingival tissue after low-level laser treatment as adjunct to SRP.

Inhibition of COX-2 and PGE2 in LPS-stimulated RAW264.7 cells by lonimacranthoide VI, a chlorogenic acid ester saponin

PubMed Central

GUAN, FUQIN; WANG, HAITING; SHAN, YU; CHEN, YU; WANG, MING; WANG, QIZHI; YIN, MIN; ZHAO, YOUYI; FENG, XU; ZHANG, JIANHUA

2014-01-01

Lonimacranthoide VI, first isolated from the flower buds of Lonicera macranthoides in our previous study, is a rare chlorogenic acid ester acylated at C-23 of hederagenin. In the present study, the anti-inflammatory effects of lonimacranthoide VI were studied. Lipopolysaccharides (LPS) induced an inflammatory response through the production of prostaglandin E2 (PGE2), and these levels were reduced when lonimacranthoide VI was pre-administered. Additionally, the mechanism of the anti-inflammatory effects of lonimacranthoide VI was investigated by measuring cyclooxygenase (COX) activity and mRNA expression. The results showed that lonimacranthoide VI inhibited mRNA expression and in vitro activity of COX-2 in a dose-dependent manner, whereas only the higher lonimacranthoide VI concentration possibly reduced COX-1 expression and in vitro activity. Taken together, these results indicate that lonimacranthoide VI is an important anti-inflammatory constituent of Lonicera macranthoides and that the anti-inflammatory effect is attributed to the inhibition of PGE2 production through COX activity and mRNA expression. PMID:25054024

Spilanthol Inhibits COX-2 and ICAM-1 Expression via Suppression of NF-κB and MAPK Signaling in Interleukin-1β-Stimulated Human Lung Epithelial Cells.

PubMed

Huang, Wen-Chung; Wu, Ling-Yu; Hu, Sindy; Wu, Shu-Ju

2018-06-30

Spilanthol a phytochemical derived from the Spilanthes acmella plant has antimicrobial, antioxidant, and anti-inflammatory properties. This study evaluated its effects on the expression of intercellular adhesion molecule 1 (ICAM-1) and inflammation-related mediators in IL-1β-stimulated human lung epithelial A549 cells. Human lung epithelial A549 cells were pretreated with various concentrations of spilanthol (3-100 μM) followed by treatment with IL-1β to induce inflammation. The protein levels of pro-inflammatory cytokines, chemokines, and prostaglandin E2 (PGE2) were measured using ELISA. Cyclooxygenase-2 (COX-2), heme oxygenase (HO-1), nuclear transcription factor kappa-B (NF-κB), and mitogen-activated protein kinase (MAPK) were measured by immunoblotting. The mRNA expression levels of ICAM-1 and MUC5AC were determined by real-time polymerase chain reaction. Spilanthol decreased the expression of PGE 2 , COX-2, TNF-α, and MCP-1. It also decreased ICAM-1 expression and suppressed monocyte adhesion to IL-1β-stimulated A549 cells. Spilanthol also significantly inhibited the phosphorylation of MAPK and I-κB. These results suggest that spilanthol exerts anti-inflammatory effects by inhibiting the expression of the pro-inflammatory cytokines, COX-2, and ICAM-1 by inhibiting the NF-κB and MAPK signaling pathways. Graphical Abstract ᅟ.

Minimizing the cancer-promotional activity of cox-2 as a central strategy in cancer prevention.

PubMed

McCarty, Mark F

2012-01-01

A recent meta-analysis examining long-term mortality in subjects who participated in controlled studies evaluating the impact of daily aspirin on vascular risk, has concluded that aspirin confers substantial protection from cancer mortality. Remarkably, low-dose aspirin was as effective as higher-dose regimens; hence this protection may be achievable with minimal risk. There is reason to believe that this protection stems primarily from inhibition of cox-2 in pre-neoplastic lesions. Since safe aspirin regimens can only achieve a partial and transitory inhibition of cox-2, it may be feasible to complement the cancer-protective benefit of aspirin with other measures which decrease cox-2 expression or which limit the bioactivity of cox-2-derived PGE2. Oxidative stress boosts cox-2 expression by up-regulating activation of NF-kappaB and MAP kinases; NADPH oxidase activation may thus promote carcinogenesis by increasing cox-2 expression while also amplifying oxidant-mediated mutagenesis. A prospective cohort study has observed that relatively elevated serum bilirubin levels are associated with a marked reduction in subsequent cancer mortality; this may reflect bilirubin's physiological role as a potent inhibitor of NADPH oxidase. It may be feasible to mimic this protective effect by supplementing with spirulina, a rich source of a phycobilin which shares bilirubin's ability to inhibit NADPH oxidase. Ancillary antioxidant measures - phase 2 inducing phytochemicals, melatonin, N-acetylcysteine, and astaxanthin - may also aid cox-2 down-regulation. The cancer protection often associated with high-normal vitamin D status may be attributable, in part, to the ability of the activated vitamin D receptor to decrease cox-2 expression while promoting PGE2 catabolism and suppressing the expression of PGE2 receptors. Diets with a relatively low ratio of omega-6 to long-chain omega-3 fats may achieve cancer protection by antagonizing the production and bioactivity of PGE2. Growth factors such as IGF-I increase cox-2 expression by several complementary mechanisms; hence, decreased cox-2 activity may play a role in the remarkably low mortality from "Western" cancers enjoyed by Third World cultures in which systemic growth factor activity was minimized by quasi-vegan diets complemented by leanness and excellent muscle insulin sensitivity. Practical strategies for achieving a modest degree of calorie restriction may also have potential for down-regulating cox-2 expression while decreasing cancer risk. Soy isoflavones, linked to reduced cancer risk in Asian epidemiology, may suppress cox-2 induction by activating ERbeta. In aggregate, these considerations suggest that a comprehensive lifestyle strategy targeting cox-2 expression and bioactivity may have tremendous potential for cancer prevention. Copyright © 2011 Elsevier Ltd. All rights reserved.

MAPK pathway activation by chronic lead-exposure increases vascular reactivity through oxidative stress/cyclooxygenase-2-dependent pathways

DOE Office of Scientific and Technical Information (OSTI.GOV)

Simões, Maylla Ronacher, E-mail: yllars@hotmail.com; Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz; Aguado, Andrea

Chronic exposure to low lead concentration produces hypertension; however, the underlying mechanisms remain unclear. We analyzed the role of oxidative stress, cyclooxygenase-2-dependent pathways and MAPK in the vascular alterations induced by chronic lead exposure. Aortas from lead-treated Wistar rats (1st dose: 10 μg/100 g; subsequent doses: 0.125 μg/100 g, intramuscular, 30 days) and cultured aortic vascular smooth muscle cells (VSMCs) from Sprague Dawley rats stimulated with lead (20 μg/dL) were used. Lead blood levels of treated rats attained 21.7 ± 2.38 μg/dL. Lead exposure increased systolic blood pressure and aortic ring contractile response to phenylephrine, reduced acetylcholine-induced relaxation and didmore » not affect sodium nitroprusside relaxation. Endothelium removal and L-NAME left-shifted the response to phenylephrine more in untreated than in lead-treated rats. Apocynin and indomethacin decreased more the response to phenylephrine in treated than in untreated rats. Aortic protein expression of gp91(phox), Cu/Zn-SOD, Mn-SOD and COX-2 increased after lead exposure. In cultured VSMCs lead 1) increased superoxide anion production, NADPH oxidase activity and gene and/or protein levels of NOX-1, NOX-4, Mn-SOD, EC-SOD and COX-2 and 2) activated ERK1/2 and p38 MAPK. Both antioxidants and COX-2 inhibitors normalized superoxide anion production, NADPH oxidase activity and mRNA levels of NOX-1, NOX-4 and COX-2. Blockade of the ERK1/2 and p38 signaling pathways abolished lead-induced NOX-1, NOX-4 and COX-2 expression. Results show that lead activation of the MAPK signaling pathways activates inflammatory proteins such as NADPH oxidase and COX-2, suggesting a reciprocal interplay and contribution to vascular dysfunction as an underlying mechanisms for lead-induced hypertension. - Highlights: • Lead-exposure increases oxidative stress, COX-2 expression and vascular reactivity. • Lead exposure activates MAPK signaling pathway. • ROS and COX-2 activation by MAPK in lead exposure • Relationship between vascular ROS and COX-2 products in lead exposure.« less

In Vivo Physiological Experiments in the Random Positioning Macine: A Study on the Rat Intestinal Transit

NASA Astrophysics Data System (ADS)

Peana, A. T.; Marzocco, S.; Bianco, G.; Autore, G.; Pinto, A.; Pippia, P.

2008-06-01

The aim of this work is to evaluate the rat intestinal transit as well as the expression of enzymes involved in this process and in gastrointestinal homeostasis as ciclooxygenase (COX-1 and COX-2), the inducibile isoform of nitric oxide synthase (iNOS), ICAM-1 and heat shock proteins HSP70 and HSP90. The modeled microgravity conditions were performed utilizing a three-dimensional clinostat, the Random Positioning Machine (RPM). Our results indicate that modeled microgravity significantly reduce rat intestinal transit. Western blot analysis on small intestine tissues of RPM rats reveals a significant increase in iNOS expression, a significant reduction in COX-2 levels, while COX-1 expression remains unaltered, and a significant increase in ICAM-1 and HSP 70 expression. Also a significant increase in HSP 90 stomach expression indicates a strong effect of simulated low g on gastrointestinal homeostasis.

Resveratrol Directly Targets COX-2 to Inhibit Carcinogenesis

PubMed Central

Zykova, Tatyana A.; Zhu, Feng; Zhai, Xiuhong; Ma, Wei-ya; Ermakova, Svetlana P.; Lee, Ki Won; Bode, Ann M.; Dong, Zigang

2008-01-01

Targeted molecular cancer therapies can potentially deliver treatment directly to a specific protein or gene to optimize efficacy and reduce adverse side effects often associated with traditional chemotherapy. Key oncoprotein and oncogene targets are rapidly being identified based on their expression, pathogenesis and clinical outcome. One such protein target is cyclooxygenase-2 (COX-2), which is highly expressed in various cancers. Research findings suggest that resveratrol (3,5,4'-trihydroxy-trans-stilbene) demonstrates non-selective COX-2 inhibition. We report herein that resveratrol (RSVL) directly binds with COX-2 and this binding is absolutely required for RSVL's inhibition of the ability of human colon adenocarcinoma HT-29 cells to form colonies in soft agar. Binding of COX-2 with RSVL was compared with two RSVL analogues, 3,3’,4’,5’5’-pentahydroxy-trans-stilbene (RSVL-2) or 3,4’,5-trimethoxy-trans-stilbene (RSVL-3). The results indicated that COX-2 binds with RSVL-2 more strongly than with RSVL, but does not bind with RSVL-3. RSVL or RSVL-2, but not RSVL-3, inhibited COX-2-mediated PGE2 production in vitro and ex vivo. HT-29 human colon adenocarcinoma cells express high levels of COX-2 and either RSVL or RSVL-2, but not RSVL-3, suppressed anchorage independent growth of these cells in soft agar. RSVL or RSVL-2 (not RSVL-3) suppressed growth of COX-2+/+ cells by 60 or 80%, respectively. Notably, cells deficient in COX-2 were unresponsive to RSVL or RSVL-2. These data suggest that the anticancer effects of RSVL or RSLV-2 might be mediated directly through COX-2. PMID:18381589

Prostaglandin metabolising enzymes and PGE2 are inversely correlated with vitamin D receptor and 25(OH)2D3 in breast cancer.

PubMed

Thill, Marc; Fischer, Dorothea; Hoellen, Friederike; Kelling, Katharina; Dittmer, Christine; Landt, Solveig; Salehin, Darius; Diedrich, Klaus; Friedrich, Michael; Becker, Steffi

2010-05-01

Breast cancer is associated with inflammatory processes based on an up-regulation of cyclooxygenase-2 (COX-2) expression. The antiproliferative effects of calcitriol (1,25(OH)(2)D(3)) mediated via the vitamin D receptor (VDR) render vitamin D a promising target in breast cancer therapy. First data suggest a correlation between vitamin D and prostaglandin metabolism. We determined the expression of VDR, COX-2, 15-PGDH and the prostaglandin receptors EP(2)/EP(4) in normal and malignant breast tissue by real-time PCR and Western blot analysis, as well as 25(OH)(2)D(3) and PGE(2) plasma levels from healthy and breast cancer patients. Significantly higher COX-2, lower VDR and lower EP(2) and EP(4) receptor protein levels in the malignant tissue and a significantly lower 15-PGDH protein level in normal breast tissue were detected. Breast cancer patients older than 45 years, diagnosed and sampled in the winter time had significantly lower 25(OH)(2)D(3) and higher PGE(2) serum levels. The inverse correlation between VDR and both COX-2 and 15-PGDH, as well as between PGE(2) and 25(OH)(2)D(3) levels, suggests a possible link between VDR-associated target genes and prostaglandin metabolism.

MicroRNA-128 inhibits proliferation and invasion of glioma cells by targeting COX-2.

PubMed

Lin, Yihai; Wu, Zhangyi

2018-06-05

MicroRNAs (miRNA), a class of small noncoding RNAs, regulates message RNA (mRNA) by targeting the 3'-untranslated region (3'-UTR) resulting in suppression of gene expression. In this study, we identified the expression and function of miR-128, which was found to be downregulated in glioma tissues and glioma cells by real time PCR. Overexpression of miR-128 mimics into LN229 and U251 cells could inhibit proliferation and invasion of glioma cells. However, the inhibitory effects of miR-128 mimics on the invasion and proliferation of glioma cells were reversed by overexpression of cyclooxygenase-2 (COX-2). Our data showed that COX-2 was a candidate target of miR-128. Luciferase activity of 3'-UTR of COX-2 was reduced in the presence of miR-128. Additionally, miR-128 obviously decreased COX-2 mRNA stability determined by real time PCR. Contrarily, we found that miR-128 inhibitor significantly increased the COX-2 mRNA expression, and elevated the protein expression of MMP9 and ki67, and promoted the proliferation of glioma cells. Furthermore, luciferase activity of the 3'-UTR was upregulated by miR-128 inhibitor. All of these results supported that miR-128 was a direct regulator of COX-2. Further studies proved that COX-2 was elevated in glioma tissues and its expression was negatively correlated with the levels of miR-128. These findings may establish miR-128 as a new potential target for the treatment of patients with gliomas. Copyright © 2018 Elsevier B.V. All rights reserved.

Determination of dietary iron requirements by full expression of iron-containing cytochrome c oxidase in the heart of broilers from 22 to 42 d of age.

PubMed

Liao, Xiudong; Ma, Chunyan; Lu, Lin; Zhang, Liyang; Luo, Xugang

2017-10-01

The present study was carried out to determine dietary Fe requirements for the full expression of Fe-containing enzyme in broilers chicks from 22 to 42 d of age. At 22 d of age, 288 Arbor Acres male chicks were randomly assigned to one of six treatments with six replicates and fed a basal maize-soyabean-meal diet (control, containing 47·0 mg Fe/kg) or the basal diet supplemented with 20, 40, 60, 80 or 100 mg Fe/kg from FeSO4.7H2O for 21 d. Regression analysis was performed to estimate the optimal dietary Fe level using quadratic models. Liver cytochrome c oxidase (Cox), heart Cox and kidney succinate dehydrogenase mRNA levels as well as heart COX activity were affected (P<0·08) by dietary Fe level, and COX mRNA level and activity in heart of broilers increased quadratically (P<0·03) as dietary Fe level increased. The estimates of dietary Fe requirements were 110 and 104 mg/kg for the full expression of Cox mRNA and for its activity in the heart of broilers, respectively. The results from this study indicate that COX mRNA level and activity in the heart are new and sensitive criteria to evaluate the dietary Fe requirements of broilers, and the dietary Fe requirements would be 104-110 mg/kg to support the full expression of COX in the heart of broiler chicks from 22 to 42 d of age, which are higher than the current National Research Council Fe requirement (80 mg/kg) of broiler chicks from 1 to 21 d or 22 to 42 d of age.

Cyclooxygenases in human and mouse skin and cultured human keratinocytes: association of COX-2 expression with human keratinocyte differentiation

NASA Technical Reports Server (NTRS)

Leong, J.; Hughes-Fulford, M.; Rakhlin, N.; Habib, A.; Maclouf, J.; Goldyne, M. E.

1996-01-01

Epidermal expression of the two isoforms of the prostaglandin H-generating cyclooxygenase (COX-1 and COX-2) was evaluated both by immunohistochemistry performed on human and mouse skin biopsy sections and by Western blotting of protein extracts from cultured human neonatal foreskin keratinocytes. In normal human skin, COX-1 immunostaining is observed throughout the epidermis whereas COX-2 immunostaining increases in the more differentiated, suprabasilar keratinocytes. Basal cell carcinomas express little if any COX-1 or COX-2 immunostaining whereas both isozymes are strongly expressed in squamous cell carcinomas deriving from a more differentiated layer of the epidermis. In human keratinocyte cultures, raising the extracellular calcium concentration, a recognized stimulus for keratinocyte differentiation, leads to an increased expression of both COX-2 protein and mRNA; expression of COX-1 protein, however, shows no significant alteration in response to calcium. Because of a recent report that failed to show COX-2 in normal mouse epidermis, we also looked for COX-1 and COX-2 immunostaining in sections of normal and acetone-treated mouse skin. In agreement with a previous report, some COX-1, but no COX-2, immunostaining is seen in normal murine epidermis. However, following acetone treatment, there is a marked increase in COX-1 expression as well as the appearance of significant COX-2 immunostaining in the basal layer. These data suggest that in human epidermis as well as in human keratinocyte cultures, the expression of COX-2 occurs as a part of normal keratinocyte differentiation whereas in murine epidermis, its constitutive expression is absent, but inducible as previously published.

Cyclooxygenase-2 expression and recurrence of colorectal adenomas: effect of aspirin chemoprevention.

PubMed

Benamouzig, Robert; Uzzan, Bernard; Martin, Antoine; Deyra, Jacques; Little, Julian; Girard, Bernard; Chaussade, Stanislas

2010-05-01

Low-dose aspirin reduces the incidence of colorectal cancer and recurrence of adenomas. Cyclooxygenase-2 (COX-2), one of its main target enzymes, is reportedly over-expressed in colorectal adenomas. To assess COX-2 expression, in relation to adenoma recurrence and the protective effect of aspirin, in a large series of colorectal adenomas, recruited from a double-blind randomised controlled trial comparing recurrences after low-dose aspirin or placebo. Follow-up colonoscopies were performed after 1 and 4 years to assess adenoma recurrence. COX-2 expression was assessed by immunohistochemistry for each adenoma obtained at baseline colonoscopy, separately for epithelium, deep stroma and overall. Architecture, grade of dysplasia, K-ras mutation, p53 and cyclin D1 expression were studied. COX-2 expression could be assessed in 219 adenomas from 136 128 adenomas (58%) from 59 patients strongly expressed COX-2. Strong COX-2 expression predominated in adenomas larger than 10 mm (84/129 vs 44/90; p=0.02) and in adenomas showing high-grade dysplasia (22/29 vs 104/188; p=0.04). Deep stromal but not epithelial initial expression of COX-2 predicted adenoma recurrence in the whole population (30/72 patients or 42% strongly expressed deep stromal COX-2 compared with 16/64 or 25% without recurrent adenoma; p=0.04). The protective effect of aspirin was mainly observed in patients in whom COX-2 initial expression was low (RR for recurrence in patients taking aspirin with low COX-2 expression: 0.59; 95% CI 0.39 to 0.90; p=0.02). There was no significant effect of aspirin at the end of the trial. Over-expression of COX-2 was frequent and predominated in large and high-grade dysplasia adenomas. Deep stromal but not epithelial initial expression of COX-2 predicted recurrence of adenomas. Aspirin did not act preferentially on patients whose initial adenomas strongly expressed COX-2.

Cyclo-oxygenase 2 expression is associated with angiogenesis and lymph node metastasis in human breast cancer.

PubMed

Costa, C; Soares, R; Reis-Filho, J S; Leitão, D; Amendoeira, I; Schmitt, F C

2002-06-01

Cyclo-oxygenases 1 and 2 (COX-1 and COX-2) are key enzymes in prostaglandin biosynthesis. COX-2 is induced by a wide variety of stimuli, and present during inflammation. COX-2 overexpression has been observed in colon, head and neck, lung, prostate, stomach, and breast cancer. In colon and gastric cancer, COX-2 expression was associated with angiogenesis. The aim of this study was to determine the relation between COX-2 expression and angiogenesis in breast cancer, and to correlate the expression of this enzyme with classic clinicopathological parameters. COX-2 expression was investigated by immunohistochemistry and western blotting analysis. The expression of COX-2 was then related to age, histological grade, nodal status, oestrogen receptor status, p53 expression,c-erb-B2 overexpression, mitotic counts, MIB-1 labelling index, apoptotic index, sialyl-Tn expression, transforming growth factor alpha expression, microvessel density, and disease free survival in 46 patients with invasive ductal breast carcinoma. By means of immunohistochemistry, COX-2 expression was detected in eight of the 46 carcinomas studied. Western blotting showed COX-2 protein expression in the same breast tumours, but not in normal adjacent tissues. The density of microvessels immunostained with anti-F-VIII related antigen was significantly higher in patients with COX-2 expression than in those without expression (p = 0.03). In addition, COX-2 was significantly associated with the presence of sialyl-Tn expression (p = 0.02), lymph node metastasis (p = 0.03), a high apoptotic index (p = 0.03), and a short disease free survival (p = 0.03) in univariate analyses. These data suggest that COX-2 expression is associated with angiogenesis, lymph node metastasis, and apoptosis in human breast cancer. Moreover, these results warrant further studies with larger series of patients to confirm the association with short disease free survival in patients with breast cancer.

Expression of cyclooxygenase-2 in transitional cell carcinoma of the urinary bladder in dogs.

PubMed

Khan, K N; Knapp, D W; Denicola, D B; Harris, R K

2000-05-01

To evaluate expression of cyclooxygenase (COX)-1 and COX-2 in the urinary bladder epithelium of clinically normal dogs and in transitional cell carcinoma cells of dogs. 21 dogs with transitional cell carcinoma of the urinary bladder and 8 dogs with clinically normal urinary bladders. COX-1 and COX-2 were evaluated by use of isoform-specific antibodies with standard immunohistochemical methods. COX-1, but not COX-2, was constitutively expressed in normal urinary bladder epithelium; however, COX-2 was expressed in neoplastic epithelium in primary tumors and in metastatic lesions of all 21 dogs and in new proliferating blood vessels in 3 dogs. Also, COX-1 was expressed in the neoplastic cells. Lack of expression of COX-2 in normal bladder epithelium and its substantial expression in transitional cell carcinoma cells suggest that this isoform may be involved in tumor cell growth. Inhibition of COX-2 is a likely mechanism of the antineoplastic effects of non steroidal antiinflammatory drugs.

Circulating cycloxygenase-2 in patients with tobacco-related intraoral squamous cell carcinoma and evaluation of its peptide inhibitors as potential antitumor agent.

PubMed

Kapoor, Vaishali; Singh, Abhay K; Dey, Sharmistha; Sharma, Suresh C; Das, Satya N

2010-12-01

The aim of this study was to quantitate circulating COX-2 levels in patients with tobacco-related intraoral cancer and to evaluate antitumor activities of COX-2 peptide inhibitors in vitro on KB cell lines. We used a novel biosensor-based surface plasmon resonance (SPR) technique for estimation of circulating COX-2 levels in 76 patients with oral cancer and 43 normal individuals. Antitumor activities of five COX-2 inhibitory peptides were evaluated using propidium iodide labeling and flow cytometry, alamar blue, MTS, and annexin-V binding assays. Patients with oral cancer showed threefold increase in serum COX-2 level when compared to normal controls (P < 0.0001). Further, late-stage tumors and lymph node metastasis were associated with significant increase in serum COX-2 levels. Patients with higher circulating COX-2 also showed higher immunoreactivity to anti-COX-2 antibody in the lesions. The peptides significantly reduced viability and inhibited growth/proliferation, induced cytotoxicity and apoptosis in tumor cells. However, no such effect was observed either on normal human leukocytes or on MCF-7 cell line that did not over express COX-2. Our results indicate that SPR may be a useful proteomic technique for quantitative assessment of COX-2 and to identify patients with high-risk oral premalignant or occult cancer, as well as in monitoring response to novel COX-2 targeting strategies. Furthermore, COX-2 peptide inhibitors appear to be a new class of potent anticancer agent for human oral carcinoma.

Gigantol isolated from the whole plants of Cymbidium goeringii inhibits the LPS-induced iNOS and COX-2 expression via NF-kappaB inactivation in RAW 264.7 macrophages cells.

PubMed

Won, Jong-Heon; Kim, Ji-Yeon; Yun, Kyung-Jin; Lee, Jin-Hee; Back, Nam-In; Chung, Hae-Gon; Chung, Sun A; Jeong, Tae-Sook; Choi, Myung-Sook; Lee, Kyung-Tae

2006-10-01

During our efforts to find bioactive natural products with anti-inflammatory activity, we isolated gigantol from the whole plants of Cymbidium goeringii (Orchidaceae) by activity-guided chromatographic fractionation. Gigantol was found to have potent inhibitory effects on LPS-induced nitric oxide (NO) and prostaglandin E (2) (PGE (2)) production in RAW 264.7 cells. Consistent with these findings, gigantol suppressed the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at the protein and mRNA levels in RAW 264.7 cells in a concentration-dependent manner. Our data also indicate that gigantol is a potent inhibitor of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta) and interleukin-6 (IL-6) release and influenced the mRNA expression levels of these cytokines in a dose-dependent manner. Furthermore, a reporter gene assay for nuclear factor kappa B (NF-kappaB) and an electromobility shift assay (EMSA) demonstrated that gigantol effectively inhibited the activation of NF-kappaB, which is necessary for the expression of iNOS, COX-2, TNF-alpha, IL-1beta and IL-6. Thus, our studies suggest that gigantol inhibits LPS-induced iNOS and COX-2 expression by blocking NF- kappaB activation.

Flavocoxid, a dual inhibitor of cyclooxygenase-2 and 5-lipoxygenase, reduces pancreatic damage in an experimental model of acute pancreatitis

PubMed Central

Polito, F; Bitto, A; Irrera, N; Squadrito, F; Fazzari, C; Minutoli, L; Altavilla, D

2010-01-01

BACKGROUND AND PURPOSE Acute pancreatitis is an autodigestive process resulting in acute inflammation of the pancreas. Accumulating evidence indicates the essential contribution of cyclooxygenase (COX)-2 and 5-lipoxygenase (5-LOX) to acute pancreatitis. We studied the effects of flavocoxid, a plant-derived dual inhibitor of COX-2 and 5-LOX, in a model of caerulein (CER)-induced acute pancreatitis. EXPERIMENTAL APPROACH Rats were given CER (80 µg·kg−1 for each of four injections at hourly intervals) or vehicle (Sham-CER). Animals were then randomized to receive flavocoxid (20 mg·kg−1 i.p.) or vehicle, 30 min after the first CER injection. Two hours after the last CER injection, we evaluated damage to the pancreas by histological methods; serum levels of amylase, lipase, leukotriene (LT)B4 and prostaglandin (PG)E2; pancreatic expression of COX-2 and 5-LOX and tumour necrosis factor-α (TNF-α) gene expression by real-time polymerase chain reaction. KEY RESULTS Caerulein induced inflammatory changes in the pancreas and raised values of the other variables measured. In CER-treated animals, but not in those given saline, flavocoxid inhibited COX-2 and 5-LOX expression, reduced serum levels of lipase and amylase and the degree of pancreatic oedema. Treatment with flavocoxid blunted the increased pancreatic TNF-α mRNA expression, serum leukotriene B4 and prostaglandin E2 levels, and protected against histological damage in terms of vacuolization and leukocyte infiltration. CONCLUSIONS AND IMPLICATIONS Our results confirm the key role of both COX-2 and 5-LOX in the inflammatory response to acute pancreatitis. Flavocoxid may provide a potential therapeutic approach to the treatment of patients at high risk of developing this life-threatening condition. PMID:20977452

Diabetes Upregulation of Cyclooxygenase 2 Contributes to Altered Coronary Reactivity After Cardiac Surgery.

PubMed

Feng, Jun; Anderson, Kelsey; Singh, Arun K; Ehsan, Afshin; Mitchell, Hunter; Liu, Yuhong; Sellke, Frank W

2017-08-01

We hypothesized that upregulation of inducible cyclooxygenase 2 (COX-2) contributes to altered coronary arteriolar reactivity early after cardioplegic arrest and cardiopulmonary bypass (CP/CPB) in patients with diabetes mellitus who are undergoing cardiac surgery. The right atrial tissue samples of nondiabetes (ND), controlled diabetes (CDM), and uncontrolled diabetes (UDM) patients undergoing cardiac surgery were harvested before and after CP/CPB. Coronary arterioles (80 to 150 μm) were dissected from the harvested atrial tissue samples, cannulated, and pressurized. The changes in diameter were measured with video microscopy. The protein expression and localization of COX-1 and COX-2 were assayed by Western blot and immunohistochemistry. In the diabetes arterioles, bradykinin-induced relaxation response was inhibited by the selective COX-2 inhibitor NS398 at baseline (p < 0.05). This effect was more pronounced in UDM arterioles than CDM (p < 0.05). After CP/CPB, bradykinin-induced responses in all groups were inhibited by NS398, but this effect was more pronounced in the UDM patients (p < 0.05). The intensities of COX-2 staining of coronary arterioles and COX-2 protein levels in myocardium were higher in diabetes than nondiabetes at baseline (p < 0.05). The post-CP/CPB protein levels of the inducible COX-2 were significantly increased compared with pre-CP/CPB values in all groups (p < 0.05), whereas this increase was higher with diabetes than with ND (p < 0.05). Furthermore, these effects were more profound in UDM than CDM (p < 0.05). Diabetes and CP/CPB are associated with upregulation in COX-2 expression in human coronary vasculature. Upregulation of COX-2 expression may contribute to bradykinin-induced coronary arteriolar relaxation in diabetic patients undergoing cardiac surgery. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

In situ aromatase expression in primary tumor is associated with estrogen receptor expression but is not predictive of response to endocrine therapy in advanced breast cancer

PubMed Central

2009-01-01

Background New, third-generation aromatase inhibitors (AIs) have proven comparable or superior to the anti-estrogen tamoxifen for treatment of estrogen receptor (ER) and/or progesterone receptor (PR) positive breast cancer. AIs suppress total body and intratumoral estrogen levels. It is unclear whether in situ carcinoma cell aromatization is the primary source of estrogen production for tumor growth and whether the aromatase expression is predictive of response to endocrine therapy. Due to methodological difficulties in the determination of the aromatase protein, COX-2, an enzyme involved in the synthesis of aromatase, has been suggested as a surrogate marker for aromatase expression. Methods Primary tumor material was retrospectively collected from 88 patients who participated in a randomized clinical trial comparing the AI letrozole to the anti-estrogen tamoxifen for first-line treatment of advanced breast cancer. Semi-quantitative immunohistochemical (IHC) analysis was performed for ER, PR, COX-2 and aromatase using Tissue Microarrays (TMAs). Aromatase was also analyzed using whole sections (WS). Kappa analysis was applied to compare association of protein expression levels. Univariate Wilcoxon analysis and the Cox-analysis were performed to evaluate time to progression (TTP) in relation to marker expression. Results Aromatase expression was associated with ER, but not with PR or COX-2 expression in carcinoma cells. Measurements of aromatase in WS were not comparable to results from TMAs. Expression of COX-2 and aromatase did not predict response to endocrine therapy. Aromatase in combination with high PR expression may select letrozole treated patients with a longer TTP. Conclusion TMAs are not suitable for IHC analysis of in situ aromatase expression and we did not find COX-2 expression in carcinoma cells to be a surrogate marker for aromatase. In situ aromatase expression in tumor cells is associated with ER expression and may thus point towards good prognosis. Aromatase expression in cancer cells is not predictive of response to endocrine therapy, indicating that in situ estrogen synthesis may not be the major source of intratumoral estrogen. However, aromatase expression in combination with high PR expression may select letrozole treated patients with longer TTP. Trial registration Sub-study of trial P025 for advanced breast cancer. PMID:19531212

Topical Application of a Bioadhesive Black Raspberry Gel Modulates Gene Expression and Reduces Cyclooxygenase 2 Protein in Human Premalignant Oral Lesions

PubMed Central

Mallery, Susan R.; Zwick, Jared C.; Pei, Ping; Tong, Meng; Larsen, Peter E.; Shumway, Brian S.; Lu, Bo; Fields, Henry W.; Mumper, Russell J.; Stoner, Gary D.

2010-01-01

Reduced expression of proapoptotic and terminal differentiation genes in conjunction with increased levels of the proinflammatory and angiogenesis-inducing enzymes, cyclooxygenase 2 (COX-2) and inducible nitric oxide synthase (iNOS), correlate with malignant transformation of oral intraepithelial neoplasia (IEN). Accordingly, this study investigated the effects of a 10% (w/w) freeze-dried black raspberry gel on oral IEN histopathology, gene expression profiles, intraepithelial COX-2 and iNOS proteins, and microvascular densities. Our laboratories have shown that freeze-dried black raspberries possess antioxidant properties and also induce keratinocyte apoptosis and terminal differentiation. Oral IEN tissues were hemisected to provide samples for pretreatment diagnoses and establish baseline biochemical and molecular variables. Treatment of the remaining lesional tissue (0.5 g gel applied four times daily for 6 weeks) began 1 week after the initial biopsy. RNA was isolated from snap-frozen IEN lesions for microarray analyses, followed by quantitative reverse transcription-PCR validation. Additional epithelial gene-specific quantitative reverse transcription-PCR analyses facilitated the assessment of target tissue treatment effects. Surface epithelial COX-2 and iNOS protein levels and microvascular densities were determined by image analysis quantified immunohistochemistry. Topical berry gel application uniformly suppressed genes associated with RNA processing, growth factor recycling, and inhibition of apoptosis. Although the majority of participants showed posttreatment decreases in epithelial iNOS and COX-2 proteins, only COX-2 reductions were statistically significant. These data show that berry gel application modulated oral IEN gene expression profiles, ultimately reducing epithelial COX-2 protein. In a patient subset, berry gel application also reduced vascular densities in the superficial connective tissues and induced genes associated with keratinocyte terminal differentiation. PMID:18559542

Indoleamine-2,3-dioxygenase 1/cyclooxygenase 2 expression prediction for adverse prognosis in colorectal cancer

PubMed Central

Ma, Wen-Juan; Wang, Xing; Yan, Wen-Ting; Zhou, Zhong-Guo; Pan, Zhi-Zhong; Chen, Gong; Zhang, Rong-Xin

2018-01-01

AIM To evaluate indoleamine-2,3-dioxygenase 1/cyclooxygenase 2 (IDO1/COX2) expression as an independent prognostic biomarker for colorectal cancer (CRC) patients. METHODS We retrospectively studied the medical records of 95 patients who received surgical resection from August 2008 to January 2010. All patients were randomly assigned to adjuvant treatment with or without celecoxib groups after surgery. We performed standard immunohistochemistry to assess the expression levels of IDO1/COX2 and evaluated the correlation of IDO1/COX2 with clinicopathological factors and overall survival (OS) outcomes. RESULTS The expression of nuclear IDO1 was significantly correlated with body mass index (P < 0.001), and IDO1 expression displayed no association with sex, age, tumor differentiation, T stage, N stage, carcinoembryonic antigen, cancer antigen 19-9, CD3+ and CD8+ tumor infiltrating lymphocytes, and COX2. In univariate analysis, we found that nuclear IDO1 (P = 0.039), nuclear/cytoplasmic IDO1 [hazard ratio (HR) = 2.044, 95% confidence interval (CI): 0.871-4.798, P = 0.039], nuclear IDO1/COX2 (HR = 3.048, 95%CI: 0.868-10.7, P = 0.0049) and cytoplasmic IDO1/COX2 (HR = 2.109, 95%CI: 0.976-4.558, P = 0.022) all yielded significantly poor OS outcomes. Nuclear IDO1 (P = 0.041), nuclear/cytoplasmic IDO1 (HR = 3.023, 95%CI: 0.585-15.61, P = 0.041) and cytoplasmic IDO1/COX2 (HR = 2.740, 95%CI: 0.764-9.831, P = 0.038) have significantly poor OS outcomes for the CRC celecoxib subgroup. In our multivariate Cox model, high coexpression of cytoplasmic IDO1/COX2 was found to be an independent predictor of poor outcome in CRC (HR = 2.218, 95%CI: 1.011-4.48, P = 0.047) and celecoxib subgroup patients (HR = 3.210, 95%CI: 1.074-9.590, P = 0.037). CONCLUSION Our results showed that cytoplasmic IDO1/COX2 coexpression could be used as an independent poor predictor for OS in CRC. PMID:29853736

Aggravation of Alzheimer's disease due to the COX-2-mediated reciprocal regulation of IL-1β and Aβ between glial and neuron cells.

PubMed

Wang, Pu; Guan, Pei-Pei; Wang, Tao; Yu, Xin; Guo, Jian-Jun; Wang, Zhan-You

2014-08-01

Alzheimer's disease (AD) is the most common form of dementia and displays the characteristics of chronic neurodegenerative disorders; amyloid plaques (AP) that contain amyloid β-protein (Aβ) accumulate in AD, which is also characterized by tau phosphorylation. Epidemiological evidence has demonstrated that long-term treatment with nonsteroidal anti-inflammatory drugs (NSAIDs) markedly reduces the risk of AD by inhibiting the expression of cyclooxygenase 2 (COX-2). Although the levels of COX-2 and its metabolic product prostaglandin (PG)E2 are elevated in the brain of AD patients, the mechanisms for the development of AD remain unknown. Using human- or mouse-derived glioblastoma and neuroblastoma cell lines as model systems, we delineated the signaling pathways by which COX-2 mediates the reciprocal regulation of interleukin-1β (IL-1β) and Aβ between glial and neuron cells. In glioblastoma cells, COX-2 regulates the synthesis of IL-1β in a PGE2 -dependent manner. Moreover, COX-2-derived PGE2 signals the activation of the PI3-K/AKT and PKA/CREB pathways via cyclic AMP; these pathways transactivate the NF-κB p65 subunit via phosphorylation at Ser 536 and Ser 276, leading to IL-1β synthesis. The secretion of IL-1β from glioblastoma cells in turn stimulates the expression of COX-2 in human or mouse neuroblastoma cells. Similar regulatory mechanisms were found for the COX-2 regulation of BACE-1 expression in neuroblastoma cells. More importantly, Aβ deposition mediated the inflammatory response of glial cells via inducing the expression of COX-2 in glioblastoma cells. These findings not only provide new insights into the mechanisms of COX-2-induced AD but also initially define the therapeutic targets of AD. © 2014 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

Indomethacin treatment prior to pentylenetetrazole-induced seizures downregulates the expression of il1b and cox2 and decreases seizure-like behavior in zebrafish larvae.

PubMed

Barbalho, Patrícia Gonçalves; Lopes-Cendes, Iscia; Maurer-Morelli, Claudia Vianna

2016-03-09

It has been demonstrated that the zebrafish model of pentylenetetrazole (PTZ)-evoked seizures and the well-established rodent models of epilepsy are similar pertaining to behavior, electrographic features, and c-fos expression. Although this zebrafish model is suitable for studying seizures, to date, inflammatory response after seizures has not been investigated using this model. Because a relationship between epilepsy and inflammation has been established, in the present study we investigated the transcript levels of the proinflammatory cytokines interleukin-1 beta (il1b) and cyclooxygenase-2 (cox2a and cox2b) after PTZ-induced seizures in the brain of zebrafish 7 days post fertilization. Furthermore, we exposed the fish to the nonsteroidal anti-inflammatory drug indomethacin prior to PTZ, and we measured its effect on seizure latency, number of seizure behaviors, and mRNA expression of il1b, cox2b, and c-fos. We used quantitative real-time PCR to assess the mRNA expression of il1b, cox2a, cox2b, and c-fos, and visual inspection was used to monitor seizure latency and the number of seizure-like behaviors. We found a short-term upregulation of il1b, and we revealed that cox2b, but not cox2a, was induced after seizures. Indomethacin treatment prior to PTZ-induced seizures downregulated the mRNA expression of il1b, cox2b, and c-fos. Moreover, we observed that in larvae exposed to indomethacin, seizure latency increased and the number of seizure-like behaviors decreased. This is the first study showing that il1b and cox-2 transcripts are upregulated following PTZ-induced seizures in zebrafish. In addition, we demonstrated the anticonvulsant effect of indomethacin based on (1) the inhibition of PTZ-induced c-fos transcription, (2) increase in seizure latency, and (3) decrease in the number of seizure-like behaviors. Furthermore, anti-inflammatory effect of indomethacin is clearly demonstrated by the downregulation of the mRNA expression of il1b and cox2b. Our results are supported by previous evidences suggesting that zebrafish is a suitable alternative for studying inflammation, seizures, and the effect of anti-inflammatory compounds on seizure suppression.

Sulforaphane protects against acrolein-induced oxidative stress and inflammatory responses: modulation of Nrf-2 and COX-2 expression.

PubMed

Qin, Wang-Sen; Deng, Yu-Hui; Cui, Fa-Cai

2016-08-01

Acrolein (2-propenal) is a reactive α, β-unsaturated aldehyde which causes a health hazard to humans. The present study focused on determining the protection offered by sulforaphane against acrolein-induced damage in peripheral blood mononuclear cells (PBMC). Acrolein-induced oxidative stress was determined through evaluating the levels of reactive oxygen species, protein carbonyl and sulfhydryl content, thiobarbituric acid reactive species, total oxidant status and antioxidant status (total antioxidant capacity, glutathione, superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase activity). Also, Nrf-2 expression levels were determined using western blot analysis. Acrolein-induced inflammation was determined through analyzing expression of cyclooxygenase-2 by western blot and PGE2 levels by ELISA. The protection offered by sulforaphane against acrolein-induced oxidative stress and inflammation was studied. Acrolein showed a significant (p < 0.001) increase in the levels of oxidative stress parameters and down-regulated Nrf-2 expression. Acrolein-induced inflammation was observed through upregulation (p < 0.001) of COX-2 and PGE2 levels. Pretreatment with sulforaphane enhanced the antioxidant status through upregulating Nrf-2 expression (p < 0.001) in PBMC. Acrolein-induced inflammation was significantly inhibited through suppression of COX-2 (p < 0.001) and PGE2 levels (p < 0.001). The present study provides clear evidence that pre-treatment with sulforaphane completely restored the antioxidant status and prevented inflammatory responses mediated by acrolein. Thus the protection offered by sulforaphane against acrolein-induced damage in PBMC is attributed to its anti-oxidant and anti-inflammatory potential.

Kaposi's Sarcoma Associated Herpes Virus (KSHV) Induced COX-2: A Key Factor in Latency, Inflammation, Angiogenesis, Cell Survival and Invasion

PubMed Central

Sharma-Walia, Neelam; Sadagopan, Sathish; Veettil, Mohanan Valiya; Kerur, Nagaraj; Chandran, Bala

2010-01-01

Kaposi's sarcoma (KS), an enigmatic endothelial cell vascular neoplasm, is characterized by the proliferation of spindle shaped endothelial cells, inflammatory cytokines (ICs), growth factors (GFs) and angiogenic factors. KSHV is etiologically linked to KS and expresses its latent genes in KS lesion endothelial cells. Primary infection of human micro vascular endothelial cells (HMVEC-d) results in the establishment of latent infection and reprogramming of host genes, and cyclooxygenase-2 (COX-2) is one of the highly up-regulated genes. Our previous study suggested a role for COX-2 in the establishment and maintenance of KSHV latency. Here, we examined the role of COX-2 in the induction of ICs, GFs, angiogenesis and invasive events occurring during KSHV de novo infection of endothelial cells. A significant amount of COX-2 was detected in KS tissue sections. Telomerase-immortalized human umbilical vein endothelial cells supporting KSHV stable latency (TIVE-LTC) expressed elevated levels of functional COX-2 and microsomal PGE2 synthase (m-PGES), and secreted the predominant eicosanoid inflammatory metabolite PGE2. Infected HMVEC-d and TIVE-LTC cells secreted a variety of ICs, GFs, angiogenic factors and matrix metalloproteinases (MMPs), which were significantly abrogated by COX-2 inhibition either by chemical inhibitors or by siRNA. The ability of these factors to induce tube formation of uninfected endothelial cells was also inhibited. PGE2, secreted early during KSHV infection, profoundly increased the adhesion of uninfected endothelial cells to fibronectin by activating the small G protein Rac1. COX-2 inhibition considerably reduced KSHV latent ORF73 gene expression and survival of TIVE-LTC cells. Collectively, these studies underscore the pivotal role of KSHV induced COX-2/PGE2 in creating KS lesion like microenvironment during de novo infection. Since COX-2 plays multiple roles in KSHV latent gene expression, which themselves are powerful mediators of cytokine induction, anti-apoptosis, cell survival and viral genome maintainence, effective inhibition of COX-2 via well-characterized clinically approved COX-2 inhibitors could potentially be used in treatment to control latent KSHV infection and ameliorate KS. PMID:20169190

Prostaglandin metabolizing enzymes in correlation with vitamin D receptor in benign and malignant breast cell lines.

PubMed

Thill, Marc; Fischer, Dorothea; Becker, Steffi; Cordes, Tim; Dittmer, Christine; Diedrich, Klaus; Salehin, Darius; Friedrich, Michael

2009-09-01

The antiproliferative effects of calcitriol (1,25(OH)2D3) mediated via the vitamin D receptor (VDR), render the biologically active form of vitamin D a promising target in breast cancer therapy. Furthermore, breast cancer is associated with inflammatory processes based on an up-regulation of cyclooxygenase-2 (COX-2) expression, the prostaglandin E2 (PGE2) synthesizing enzyme. The PGE2 metabolizing enzyme, 15-hydroxyprostaglandin dehydrogenase (15-PGDH) is described as a tumor suppressor in cancer. First references suggest a correlation between vitamin D and prostaglandin metabolism through the impact of 1,25(OH)2D3 on the expression of COX-2 and 15-PGDH. The expression of VDR, COX-2 and 15-PGDH in benign MCF-10F and malignant MCF-7 breast cells was determined by real-time PCR (RT-PCR) and Western blot analysis. Although the RT-PCR data were divergent from those obtained from the Western blot analysis, the COX-2 protein expression was MCF-7 2-fold higher in the MCF-7 compared to the MCF-10F cells. Moreover, a correlation of 15-PGDH to VDR by RT-PCR was found in both cell lines. The VDR protein levels were inversely correlated to the 15-PGDH protein levels and revealed that the MCF-10F cells had the highest VDR expression. A possible link between VDR-associated target genes and prostaglandin metabolism is suggested.

Phloretin inhibits interleukin-1β-induced COX-2 and ICAM-1 expression through inhibition of MAPK, Akt, and NF-κB signaling in human lung epithelial cells.

PubMed

Huang, Wen-Chung; Wu, Shu-Ju; Tu, Rong-Syuan; Lai, You-Rong; Liou, Chian-Jiun

2015-06-01

Phloretin, a flavonoid isolated from the apple tree, is reported to have anti-inflammatory, anti-oxidant, and anti-adiposity effects. In this study, we evaluated the suppressive effects of phloretin on intercellular adhesion molecule 1 (ICAM-1) and cyclooxygenase (COX)-2 expression in IL-1β-stimulated human lung epithelial A549 cells. The cells were pretreated with various concentrations of phloretin (3-100 μM), followed by induced inflammation by IL-1β. Phloretin inhibited levels of prostaglandin E2, decreased COX-2 expression, and suppressed IL-8, monocyte chemotactic protein 1, and IL-6 production. It also decreased ICAM-1 gene and protein expression and suppressed monocyte adhesion to inflammatory A549 cells. Phloretin also significantly inhibited Akt and mitogen-activated protein kinase (MAPK) phosphorylation and decreased nuclear transcription factor kappa-B (NF-κB) subunit p65 protein translocation into the nucleus. In addition, ICAM-1 and COX-2 expression was suppressed by pretreatment with both MAPK inhibitors and phloretin in inflammatory A549 cells. However, phlorizin, a derivative of phloretin, did not suppress the inflammatory response in IL-1β-stimulated A549 cells. These results suggest that phloretin might have an anti-inflammatory effect by inhibiting proinflammatory cytokine, COX-2, and ICAM-1 expression via blocked NF-κB and MAPK signaling pathways.

Characterization of prostaglandin E2 generation through the cyclooxygenase (COX)-2 pathway in human neutrophils

PubMed Central

St-Onge, Mireille; Flamand, Nicolas; Biarc, Jordane; Picard, Serge; Bouchard, Line; Dussault, Andrée-Anne; Laflamme, Cynthia; James, Michael J.; Caughey, Gillian E.; Cleland, Leslie G.; Borgeat, Pierre; Pouliot, Marc

2010-01-01

In the present study, we characterized the generation of prostaglandin (PG)E2 in human neutrophils. We found that the Ca2+-dependent type IV cytosolic phospholipase A2 (cPLA2) was pivotally involved in the COX-2-mediated generation of PGE2 in response to a calcium ionophore, as determined by the use of selected PLA2 inhibitors. PGE2 biosynthesis elicited by bacterial-derived peptides or by phagocytic stimuli acting on cell surface receptors also showed to be dependent on cPLA2 activity. We then assessed metabolism of unesterified arachidonic acid (AA), and observed that PGE2 production becomes favored over that of LTB4 with higher AA concentrations. Withdrawal of calcium prevented the generation of PGE2 in response to a calcium ionophore but did not affect the up-regulation of COX-2 or its capacity to convert AA, thus limiting its implication at the level of cPLA2 activation. Of the main eicosanoids produced by neutrophils, only LTB4 was able to up-regulate COX-2 expression. Finally, the only PGE synthase isoform found in neutrophils is microsomal PGE synthase-1; it co-localized with COX-2 and its expression appeared mainly constitutive. These results highlight key differences in regulatory processes of the 5-LO and COX pathways, and enhance our knowledge at several levels in the PGE2 biosynthesis in neutrophils. PMID:17643350

COX-2 expression and outcome in canine nasal carcinomas treated with hypofractionated radiotherapy.

PubMed

Belshaw, Z; Constantio-Casas, F; Brearley, M J; Dunning, M D; Holmes, M A; Dobson, J M

2011-06-01

The expression of cyclooxygenase isoform 2 (COX-2) in canine nasal carcinomas has been well documented. COX-2 expression has proven to be a prognostic factor in several human tumours. The aims of this study were to assess the correlation between immunohistochemical COX-2 expression and prognosis using rhinoscopic biopsies from 42 dogs with nasal carcinomas treated with hypofractionated radiotherapy, and to establish a replicable COX-2 scoring system. Ninety per cent of sections evaluated were COX-2 positive with a mean score of 6.6 (median 8.0; range 0-12). Neither COX-2 expression nor tumour type had a significant correlation with survival. There are likely to be many as yet unidentified variants which contribute to length of survival in dogs with nasal carcinomas. Immunohistochemical COX-2 expression appears unlikely to be of prognostic significance for canine nasal carcinoma. © 2010 Blackwell Publishing Ltd.

Celecoxib enhances the radiosensitivity of HCT116 cells in a COX-2 independent manner by up-regulating BCCIP

PubMed Central

Xu, Xiao-Ting; Hu, Wen-Tao; Zhou, Ju-Ying; Tu, Yu

2017-01-01

It has been reported that celecoxib, a cyclooxygenase-2 (COX-2)-selective nonsteroidal anti-inflammatory drug (NSAID), regulates the radiosensitivity of several cancer cells. BCCIP (BRCA2 and CDKN1A interacting protein) plays a critical role in maintaining the critical functions of p53 in tumor suppression and response to therapy. However, whether the effect of celecoxib on the radiosensitivity of colorectal cancer (CRC) cells is dependent on BCCIP is largely unclear. In this study, we found that celecoxib enhanced the radiosensitivity of HeLa (a human cervical carcinoma cell line), A549 (a human lung carcinoma cell line), and HCT116 cells (a human CRC cells line). Among these cells, COX-2 expression was undetected in HCT116 cells. Treatment with celecoxib significantly increased BCCIP expression in COX-2 negative HCT116 cells. Knockdown of BCCIP obviously abrogated the enhanced radiosensitivity of HCT116 cells induced by celecoxib. A combination of celecoxib and irradiation treatment induced much more γ-H2AX foci formation, higher levels of radiation injury-related proteins phosphorylation, G2/M arrest, apoptosis, and p53 and p21 expression, and lower levels of Cyclin B1 in HCT116 cells than those in cells treated with irradiation alone. However, these changes were undetected in BCCIP-silenced HCT116 cells. Therefore, these data suggest that BCCIP gene may be a radiosensitivity-related gene in CRC. Celecoxib affects the functions of p53 and inhibits the recovery from the irradiation-induced injury by up-regulating the expression of BCCIP, and subsequently regulates the expressions of genes such as p21 and Cyclin B1 to enhance the radiosensitivity of HCT116 cells in a COX-2 independent manner. PMID:28386336

Radiation-induced cyclooxygenase 2 up-regulation is dependent on redox status in prostate cancer cells.

PubMed

Li, Lingyun; Steinauer, Kirsten K; Dirks, Amie J; Husbeck, Bryan; Gibbs, Iris; Knox, Susan J

2003-12-01

Cyclooxygenase 2 (COX2) is the inducible isozyme of COX, a key enzyme in arachidonate metabolism and the conversion of arachidonic acid (AA) to prostaglandins (PGs) and other eicosanoids. Previous studies have demonstrated that the COX2 protein is up-regulated in prostate cancer cells after irradiation and that this results in elevated levels of PGE(2). In the present study, we further investigated whether radiation-induced COX2 up-regulation is dependent on the redox status of cells from the prostate cancer cell line PC-3. l-Buthionine sulfoximine (BSO), which inhibits gamma glutamyl cysteine synthetase (gammaGCS), and the antioxidants alpha-lipoic acid and N-acetyl-l-cysteine (NAC) were used to modulate the cellular redox status. BSO decreased the cellular GSH level and increased cellular reactive oxygen species (ROS) in PC-3 cells, whereas alpha-lipoic acid and NAC increased the GSH level and decreased cellular ROS. Both radiation and the oxidant H(2)O(2) had similar effects on COX2 up-regulation and PGE(2) production in PC-3 cells, suggesting that radiation-induced COX2 up-regulation is secondary to the production of ROS. The relative increases in COX2 expression and PGE(2) production induced by radiation and H(2)O(2) were even greater when PC-3 cells were pretreated with BSO. When the cells were pretreated with alpha-lipoic acid or NAC for 24 h, both radiation- and H(2)O(2)-induced COX2 up-regulation and PGE(2) production were markedly inhibited. These results demonstrate that radiation-induced COX2 up-regulation in prostate cancer cells is modulated by the cellular redox status. Radiation-induced increases in ROS levels contribute to the adaptive response of PC-3 cells, resulting in elevated levels of COX2.

Infrared (810-nm) low-level laser therapy on rat experimental knee inflammation.

PubMed

Pallotta, Rodney Capp; Bjordal, Jan Magnus; Frigo, Lúcio; Leal Junior, Ernesto Cesar Pinto; Teixeira, Simone; Marcos, Rodrigo Labat; Ramos, Luciano; Messias, Felipe de Moura; Lopes-Martins, Rodrigo Alvaro Brandão

2012-01-01

Arthritis of the knee is the most common type of joint inflammatory disorder and it is associated with pain and inflammation of the joint capsule. Few studies address the effects of the 810-nm laser in such conditions. Here we investigated the effects of low-level laser therapy (LLLT; infrared, 810-nm) in experimentally induced rat knee inflammation. Thirty male Wistar rats (230-250 g) were anesthetized and injected with carrageenan by an intra-articular route. After 6 and 12 h, all animals were killed by CO(2) inhalation and the articular cavity was washed for cellular and biochemical analysis. Articular tissue was carefully removed for real-time PCR analysis in order to evaluate COX-1 and COX-2 expression. LLLT was able to significantly inhibit the total number of leukocytes, as well as the myeloperoxidase activity with 1, 3, and 6 J (Joules) of energy. This result was corroborated by cell counting showing the reduction of polymorphonuclear cells at the inflammatory site. Vascular extravasation was significantly inhibited at the higher dose of energy of 10 J. Both COX-1 and 2 gene expression were significantly enhanced by laser irradiation while PGE(2) production was inhibited. Low-level laser therapy operating at 810 nm markedly reduced inflammatory signs of inflammation but increased COX-1 and 2 gene expression. Further studies are necessary to investigate the possible production of antiinflammatory mediators by COX enzymes induced by laser irradiation in knee inflammation.

Expression and significance of cyclooxygenase-2 mRNA in benign and malignant ascites

PubMed Central

Lu, Jing; Li, Xiao-Feng; Kong, Li-Xia; Ma, Lin; Liao, Su-Huan; Jiang, Chang-You

2013-01-01

AIM: To investigate the mRNA expression of cyclooxygensae-2 (COX-2) in benign and malignant ascites, and to explore the difference in COX-2 mRNA expression among different diseases. METHODS: A total of 36 samples were collected from the Fifth Affiliated Hospital of Sun Yat-Sen University and divided into two experimental groups: benign ascites (n = 21) and malignant ascites (n = 15). Benign ascites included cirrhotic ascites (n = 10) and tuberculous ascites (n = 5). Malignant ascites included oophoroma (n = 7), cancer of colon (n = 5), cancer of the liver (n = 6), gastric cancer (n = 2), and bladder carcinoma (n = 1). The mRNA expression of COX-2 in ascites was examined with reverse transcriptase polymerase chain reaction (RT-PCR) technology, and the positive rate of COX-2 mRNA was compared between different diseases. RESULTS: The positive rate of COX-2 mRNA in malignant ascites was 42.9% (9/21), which was significantly higher than in benign ascites, 6.7% (1/15), difference being significant between these two groups (χ2 = 4.051, P = 0.044). The proportion of the positive rate in the malignant ascites was as follows: ovarian cancers 57.1% (4/7), colon cancer 40.0% (2/5), liver cancer 33.3% (2/6), gastric cancer 50.0% (1/2), and bladder cancer 0.00% (0/1). However, there was no significant difference in COX-2 mRNA expression among various tumors with malignant ascites (χ2 = 1.614, P = 0.806). Among the benign ascites, COX-2 mRNA levels were different between the tuberculous ascites (0/5) and cirrhotic ascites (1/10), but there was no significant difference (P = 1.000). CONCLUSION: COX-2 mRNA, detected by RT-PCR, is useful in the differential diagnosis of benign and malignant ascites, which also has potential value in the clinical diagnosis of tumors. PMID:24187465

Flavocoxid, a dual inhibitor of cyclooxygenase-2 and 5-lipoxygenase, reduces pancreatic damage in an experimental model of acute pancreatitis.

PubMed

Polito, F; Bitto, A; Irrera, N; Squadrito, F; Fazzari, C; Minutoli, L; Altavilla, D

2010-11-01

Acute pancreatitis is an autodigestive process resulting in acute inflammation of the pancreas. Accumulating evidence indicates the essential contribution of cyclooxygenase (COX)-2 and 5-lipoxygenase (5-LOX) to acute pancreatitis. We studied the effects of flavocoxid, a plant-derived dual inhibitor of COX-2 and 5-LOX, in a model of caerulein (CER)-induced acute pancreatitis. Rats were given CER (80 µg·kg⁻¹ for each of four injections at hourly intervals) or vehicle (Sham-CER). Animals were then randomized to receive flavocoxid (20 mg·kg⁻¹ i.p.) or vehicle, 30 min after the first CER injection. Two hours after the last CER injection, we evaluated damage to the pancreas by histological methods; serum levels of amylase, lipase, leukotriene (LT)B₄ and prostaglandin (PG)E₂ ; pancreatic expression of COX-2 and 5-LOX and tumour necrosis factor-α (TNF-α) gene expression by real-time polymerase chain reaction. Caerulein induced inflammatory changes in the pancreas and raised values of the other variables measured. In CER-treated animals, but not in those given saline, flavocoxid inhibited COX-2 and 5-LOX expression, reduced serum levels of lipase and amylase and the degree of pancreatic oedema. Treatment with flavocoxid blunted the increased pancreatic TNF-α mRNA expression, serum leukotriene B₄ and prostaglandin E₂ levels, and protected against histological damage in terms of vacuolization and leukocyte infiltration. Our results confirm the key role of both COX-2 and 5-LOX in the inflammatory response to acute pancreatitis. Flavocoxid may provide a potential therapeutic approach to the treatment of patients at high risk of developing this life-threatening condition. © 2010 The Authors. British Journal of Pharmacology © 2010 The British Pharmacological Society.

[Effect of M8046 on expression of COX-2/PGE2 in spinal cord and DRG in rats with neuropathic pain].

PubMed

Ou, Guo-Kun; Wang, Rui-Xian; Li, Jia-Jia; Cao, Hong; Lian, Qing-Quan; Li, Jun

2013-03-01

To investigate the effects of glucocorticoid receptor antagonist-M8046 on the behavior and the cyclooxygenase-2/prostaglandin E2( COX-2/PGE2) expression in spinal cord dorsal horn and dorsal root ganglia (DRG) in chronic constrictive injury (CCI) rats. One hundred and forty-four male SD rats were randomly divided into 4 groups, 36 rats in each group: Sham operation group (Sham), chronic constrictive group (CCI), M8046 treated group (M8046) and solvent controlled group (Sc). M8046 3 mg/(kg x d) intraperitoneal injection was given after operation in group M8046. Paw thennal withdrawal (PTWL) and paw mechanical withdrawal threshold (PMWT) of rats were measured on 2 pre-operative and 1, 3, 7, 10, 14 post-operative days. The spinal cord and L15 DRG of the operated side was removed at 3, 7, 14 days after surgery. The change of COX-2 and PGE2 expression was determined by immunohistochemical staining and ELISA separately. PTWL and PMWT in CCI group were significantly lower than those in Sham group on every post-operative day (P < 0.05). PTWL and PMWT in M8046 group were significantly higher than those in CCI group on 7, 10, 14 post-operative day (P < 0.05). In spinal dorsal horn, the level of COX-2 and PGE2 expression in CCI group was significantly higher than that in Sham group (P < 0.05). M8046 could significantly attenuate the activation of COX-2 and PGE2 induced by CCI (P < 0.05). The expression of COX-2 and PGE2 in DRG was similar to that in spinal dorsal horn. The effects of M8046 ameliorate the CCI-induced neuropathic pain may be related to attenuate the expression of COX-2 and PGE2 in spinal cord and DRG.

Eupatolide inhibits lipopolysaccharide-induced COX-2 and iNOS expression in RAW264.7 cells by inducing proteasomal degradation of TRAF6.

PubMed

Lee, Jongkyu; Tae, Nara; Lee, Jung Joon; Kim, Taeho; Lee, Jeong-Hyung

2010-06-25

Inula britannica is a traditional medicinal plant used to treat bronchitis, digestive disorders, and inflammation in Eastern Asia. Here, we identified eupatolide, a sesquiterpene lactone from I. britannica, as an inhibitor of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression. Eupatolide inhibited the production of nitric oxide (NO) and prostaglandin E(2) (PGE(2)) as well as iNOS and COX-2 protein expression in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Eupatolide dose-dependently decreased the mRNA levels and the promoter activities of COX-2 and iNOS in LPS-stimulated RAW264.7 cells. Moreover, eupatolide significantly suppressed the LPS-induced expression of nuclear factor-kappa B (NF-kappaB) and activator protein-1 (AP-1) reporter genes. Pretreatment of eupatolide inhibited LPS-induced phosphorylation and degradation of I kappaB alpha, and phosphorylation of RelA/p65 on Ser-536 as well as the activation of mitogen-activated protein kinases (MAPKs) and Akt in LPS-stimulated RAW264.7 cells. Eupatolide induced proteasomal degradation of tumor necrosis factor receptor-associated factor-6 (TRAF6), and subsequently inhibited LPS-induced TRAF6 polyubiquitination. These results suggest that eupatolide blocks LPS-induced COX-2 and iNOS expression at the transcriptional level through inhibiting the signaling pathways such as NF-kappaB and MAPKs via proteasomal degradation of TRAF6. Taken together, eupatolide may be a novel anti-inflammatory agent that induces proteasomal degradation of TRAF6, and a valuable compound for modulating inflammatory conditions. (c) 2010 Elsevier B.V. All rights reserved.

STIM1 Overexpression Promotes Colorectal Cancer Progression, Cell Motility and COX-2 Expression

PubMed Central

Wang, Jaw-Yuan; Sun, Jianwei; Huang, Ming-Yii; Wang, Yu-Shiuan; Hou, Ming-Feng; Sun, Yan; He, Huifang; Krishna, Niveditha; Chiu, Siou-Jin; Lin, Shengchen; Yang, Shengyu; Chang, Wei-Chiao

2014-01-01

Tumor metastasis is the major cause of death among cancer patients, with more than 90% of cancer-related death attributable to the spreading of metastatic cells to secondary organs. Store-operated Ca2+ entry (SOCE) is the predominant Ca2+ entry mechanism in most cancer cells, and STIM1 is the endoplasmic reticulum (ER) Ca2+ sensor for store-operated channels (SOC). Here we reported that the STIM1 was overexpressed in colorectal cancer (CRC) patients. STIM1 overexpression in CRC was significantly associated with tumor size, depth of invasion, lymphnode metastasis status and serum levels of carcinoembryonic antigen. Furthermore, ectopic expression of STIM1 promoted CRC cell motility, while depletion of STIM1 with shRNA inhibited CRC cell migration. Our data further suggested that STIM1 promoted CRC cell migration through increasing the expression of cyclooxygenase-2 (COX-2) and production of prostaglandin E2 (PGE2). Importantly, ectopically expressed COX-2 or exogenous PGE2 were able to rescue migration defect in STIM1 knockdown CRC cells, and inhibition of COX-2 with ibuprofen and indomethacin abrogated STIM1-mediated CRC cell motility. In short, our data provided clinicopathological significance for STIM1 and store-operated Ca2+ entry in CRC progression, and implicated a role for COX-2 in STIM1-mediated CRC metastasis. Our studies also suggested a new approach to inhibit STIM1-mediated metastasis with COX-2 inhibitors. PMID:25381814

Ubiquitin-proteasomal degradation of COX-2 in TGF-β stimulated human endometrial cells is mediated through endoplasmic reticulum mannosidase I.

PubMed

Singh, Mohan; Chaudhry, Parvesh; Parent, Sophie; Asselin, Eric

2012-01-01

Cyclooxygenase (COX)-2 is a key regulatory enzyme in the production of prostaglandins (PG) during various physiological processes. Mechanisms of COX-2 regulation in human endometrial stromal cells (human endometrial stromal cells) are not fully understood. In this study, we investigate the role of TGF-β in the regulation of COX-2 in human uterine stromal cells. Each TGF-β isoform decreases COX-2 protein level in human uterine stromal cells in Smad2/3-dependent manner. The decrease in COX-2 is accompanied by a decrease in PG synthesis. Knockdown of Smad4 using specific small interfering RNA prevents the decrease in COX-2 protein, confirming that Smad pathway is implicated in the regulation of COX-2 expression in human endometrial stromal cells. Pretreatment with 26S proteasome inhibitor, MG132, significantly restores COX-2 protein and PG synthesis, indicating that COX-2 undergoes proteasomal degradation in the presence of TGF-β. In addition, each TGF-β isoform up-regulates endoplasmic reticulum (ER)-mannosidase I (ERManI) implying that COX-2 degradation is mediated through ER-associated degradation pathway in these cells. Furthermore, inhibition of ERManI activity using the mannosidase inhibitor (kifunensine), or small interfering RNA-mediated knockdown of ERManI, prevents TGF-β-induced COX-2 degradation. Taken together, these studies suggest that TGF-β promotes COX-2 degradation in a Smad-dependent manner by up-regulating the expression of ERManI and thereby enhancing ER-associated degradation and proteasomal degradation pathways.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Bor-Ren; Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan; Tsai, Cheng-Fang

We investigated the interaction between proinflammatory and inflammatory responses caused by Staphylococcus aureus-derived lipoteichoic acid (LTA) in primary cultured microglial cells and BV-2 microglia. LTA induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein levels increase in a concentration- and time-dependent manner. Meanwhile, LTA also increased nitric oxide (NO) and PGE{sub 2} production in microglia. Administration of TLR2 antagonist effectively inhibited LTA-induced NO, iNOS, and COX-2 expression. Moreover, treatment of cells with LTA caused a time-dependent activation of ERK, p38, JNK, as well as AKT. We also found that LTA-induced iNOS and COX-2 up-regulation were attenuated by p38, JNK,more » and PI3-kinase inhibitors. On the other hand, LTA-enhanced HO-1 expression was attenuated by p38 and PI3-kinase inhibitors. Treatment of cells with NF-κB and AP-1 inhibitors antagonized LTA-induced iNOS and COX-2 expression. However, only NF-κB inhibitors reduced LTA-induced HO-1 expression in microglia. Furthermore, stimulation of cells with LTA also activated IκBα phosphorylation, p65 phosphorylation at Ser{sup 536}, and c-Jun phosphorylation. Moreover, LTA-induced increases of κB-DNA and AP-1-DNA binding activity were inhibited by p38, JNK, and PI3-kinase inhibitors. HO-1 activator CoPP IX dramatically reversed LTA-induced iNOS expression. Our results provided mechanisms linking LTA and inflammation/anti-inflammation, and indicated that LTA plays a regulatory role in microglia activation. - Highlights: • LTA causes an increase in iNOS, COX-2, and HO-1 expression in microglia. • LTA induces iNOS and COX-2 expression through TLR-2/NF-κB and AP-1 pathways. • HO-1 expression is regulated through p38, JNK, PI3K/AKT and AP-1 pathways. • Induced HO-1 reduces LTA-induced iNOS expression. • LTA plays a regulatory role on inflammatory/anti-inflammatory responses.« less

HGF Mediates the Anti-inflammatory Effects of PRP on Injured Tendons

PubMed Central

Zhang, Jianying; Middleton, Kellie K.; Fu, Freddie H.; Im, Hee-Jeong; Wang, James H-C.

2013-01-01

Platelet-rich plasma (PRP) containing hepatocyte growth factor (HGF) and other growth factors are widely used in orthopaedic/sports medicine to repair injured tendons. While PRP treatment is reported to decrease pain in patients with tendon injury, the mechanism of this effect is not clear. Tendon pain is often associated with tendon inflammation, and HGF is known to protect tissues from inflammatory damages. Therefore, we hypothesized that HGF in PRP causes the anti-inflammatory effects. To test this hypothesis, we performed in vitro experiments on rabbit tendon cells and in vivo experiments on a mouse Achilles tendon injury model. We found that addition of PRP or HGF decreased gene expression of COX-1, COX-2, and mPGES-1, induced by the treatment of tendon cells in vitro with IL-1β. Further, the treatment of tendon cell cultures with HGF antibodies reduced the suppressive effects of PRP or HGF on IL-1β-induced COX-1, COX-2, and mPGES-1 gene expressions. Treatment with PRP or HGF almost completely blocked the cellular production of PGE2 and the expression of COX proteins. Finally, injection of PRP or HGF into wounded mouse Achilles tendons in vivo decreased PGE2 production in the tendinous tissues. Injection of platelet-poor plasma (PPP) however, did not reduce PGE2 levels in the wounded tendons, but the injection of HGF antibody inhibited the effects of PRP and HGF. Further, injection of PRP or HGF also decreased COX-1 and COX-2 proteins. These results indicate that PRP exerts anti-inflammatory effects on injured tendons through HGF. This study provides basic scientific evidence to support the use of PRP to treat injured tendons because PRP can reduce inflammation and thereby reduce the associated pain caused by high levels of PGE2. PMID:23840657

Cyclooxygenase metabolites mediate glomerular monocyte chemoattractant protein-1 formation and monocyte recruitment in experimental glomerulonephritis.

PubMed

Schneider, A; Harendza, S; Zahner, G; Jocks, T; Wenzel, U; Wolf, G; Thaiss, F; Helmchen, U; Stahl, R A

1999-02-01

Monocyte chemoattractant protein-1 (MCP-1) has been shown to play a significant role in the recruitment of monocytes/macrophages in experimental glomerulonephritis. Whereas a number of inflammatory mediators have been characterized that are involved in the expression of MCP-1 in renal disease, little is known about repressors of chemokine formation in vivo. We hypothesized that cyclooxygenase (COX) products influence the formation of MCP-1 and affect inflammatory cell recruitment in glomerulonephritis. The effect of COX inhibitors was evaluated in the antithymocyte antibody model and an anti-glomerular basement membrane model of glomerulonephritis. Rats were treated with the COX-1/COX-2 inhibitor indomethacin and the selective COX-2 inhibitors meloxicam and SC 58125. Animals were studied at 1 hour, 24 hours, and 5 days after induction of the disease. Indomethacin, to a lesser degree the selective COX-2 inhibitors, enhanced glomerular MCP-1 and RANTES mRNA levels. Indomethacin enhanced glomerular monocyte chemoattractant activity an the infiltration of monocytes/macrophages at 24 hours and 5 days. Our studies demonstrate that COX products may serve as endogenous repressors of MCP-1 formation in experimental glomerulonephritis. The data suggest that COX-1 and COX-2 products mediate these effects differently because the selective COX-2 inhibitors had less influence on chemokine expression.

Macrophages From Irradiated Tumors Express Higher Levels of iNOS, Arginase-I and COX-2, and Promote Tumor Growth

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tsai, C.-S.; Graduate Institute of Clinical Medical Sciences, Chang Gung University, Taiwan; Chen, F.-H.

2007-06-01

Purpose: To investigate the effects of single and fractionated doses of radiation on tumors and tumor-associated macrophages (TAMs), and to elucidate the potential of TAMs to influence tumor growth. Methods and Materials: A murine prostate cell line, TRAMP-C1, was grown in C57Bl/6J mice to 4-mm tumor diameter and irradiated with either 25 Gy in a single dose, or 60 Gy in 15 fractions. The tumors were removed at the indicated times and assessed for a variety of markers related to TAM content, activation status, and function. Results: In tumors receiving a single radiation dose, arginase (Arg-I), and cycloxygenase-2 (COX-2) mRNAmore » expression increased as a small transient wave within 24 h and a larger persistent wave starting after 3 days. Inducible nitric oxide synthase (iNOS) mRNA was elevated only after 3 days and continued to increase up to 3 weeks. After fractionated irradiation, Arg-1 and COX-2 mRNA levels increased within 5 days, whereas iNOS was increased only after 10 fractions of irradiation had been given. Increased levels of Arg-I, COX-2, and, to a lesser extent, iNOS protein were found to associate with TAMs 1-2 weeks after tumor irradiation. Function of TAMs were compared by mixing them with TRAMP-C1 cells and injecting them into mice; TRAMP-C1 cells mixed with TAMs from irradiated tumors appeared earlier and grew significantly faster than those mixed with TAMs from unirradiated tumors or TRAMP-C1 alone. Conclusions: Tumor-associated macrophages in the postirradiated tumor microenvironment express higher levels of Arg-1, COX-2, and iNOS, and promote early tumor growth in vivo.« less

Elevated interleukin 6 is induced by prostaglandin E2 in a murine model of inflammation: possible role of cyclooxygenase-2.

PubMed Central

Hinson, R M; Williams, J A; Shacter, E

1996-01-01

Injection of mineral oils such as pristane into the peritoneal cavities of BALB/c mice results in a chronic peritonitis associated with high tissue levels of interleukin 6 (IL-6). Here we show that increased prostaglandin E2 (PGE2) synthesis causes induction of IL-6 and that expression of an inducible cyclooxygenase, Cox-2, may mediate this process. Levels of both PGE2 and IL-6 are elevated in inflammatory exudates from pristane-treated mice compared with lavage samples from untreated mice. The Cox-2 gene is induced in the peritoneal macrophage fraction isolated from the mice. A cause and effect relationship between increased macrophage PGE2 and IL-6 production is shown in vitro. When peritoneal macrophages are activated with an inflammatory stimulus (polymerized albumin), the Cox-2 gene is induced and secretion of PGE2 and IL-6 increases, with elevated PGE2 appearing before IL-6. Cotreatment with 1 microM indomethacin inhibits PGE2 production by the cells and reduces the induction of IL-6 mRNA but has no effect on Cox-2 mRNA, consistent with the fact that the drug inhibits catalytic activity of the cyclooxygenase but does not affect expression of the gene. Addition of exogenous PGE2 to macrophages induces IL-6 protein and mRNA synthesis, indicating that the eicosanoid stimulates IL-6 production at the level of gene expression. PGE2-stimulated IL-6 production is unaffected by addition of indomethacin. Taken together with the earlier finding that indomethacin diminishes the elevation of IL-6 in pristane-treated mice, the results show that PGE2 can induce IL-6 production in vivo and implicate expression of the Cox-2 gene in the regulation of this cytokine. Images Fig. 2 Fig. 4 Fig. 5 Fig. 6 Fig. 8 PMID:8643498

USP22 acts as an oncogene by regulating the stability of cyclooxygenase-2 in non-small cell lung cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xiao, Haibo; Tian, Yue; Yang, Yang

2015-05-08

The histone ubiquitin hydrolase ubiquitin-specific protease 22 (USP22) is an epigenetic modifier and an oncogene that is upregulated in many types of cancer. In non-small cell lung cancer (NSCLC), aberrant expression of USP22 is a predictor of poor survival, as is high expression of cyclooxygenase-2 (COX-2). Despite its oncogenic role, few substrates of USP22 have been identified and its mechanism of action in cancer remains unclear. Here, we identified COX-2 as a direct substrate of USP22 and showed that its levels are modulated by USP22 mediated deubiquitination. Silencing of USP22 downregulated COX-2, decreased its half-life, and inhibited lung carcinoma cellmore » proliferation by directly interacting with and modulating the stability and activity of COX-2 through the regulation of its ubiquitination status. The findings of the present study suggest a potential mechanism underlying the oncogenic role of USP22 mediated by the modulation of the stability and activity of COX-2. - Highlights: • USP22 interacts with COX-2. • USP22 deubiquitinates and stabilizes COX-2. • USP22 is required for COX-2-mediated upregulation of prostaglandin E2.« less

Cyclooxygenase and lipoxygenase gene expression in the inflammogenesis of breast cancer.

PubMed

Kennedy, Brian M; Harris, Randall E

2018-05-07

We examined the expression of major inflammatory genes, cyclooxygenase-1 and 2 (COX1, COX2) and arachidonate 5-lipoxygenase (ALOX5) in 1090 tumor samples of invasive breast cancer from The Cancer Genome Atlas (TCGA). Mean cyclooxygenase expression (COX1 + COX2) ranked in the upper 99th percentile of all 20,531 genes and surprisingly, the mean expression of COX1 was more than tenfold higher than COX2. Highly significant correlations were observed between COX2 with eight tumor-promoting genes (EGR2, IL6, RGS2, B3GNT5, SGK1, SLC2A3, SFRP1 and ETS2) and between ALOX5 and ten tumor promoter genes (CD33, MYOF1, NLRP1, GAB3, CD4, IFR8, CYTH4, BTK, FGR, CD37). Expression of CYP19A1 (aromatase) was significantly correlated with COX2, but only in tumors positive for ER, PR and HER2. Tumor-promoting genes correlated with the expression of COX1, COX2, and ALOX5 are known to effectively increase mitogenesis, mutagenesis, angiogenesis, cell survival, immunosuppression and metastasis in the pathogenesis of breast cancer.

Role of HCV Core gene of genotype 1a and 3a and host gene Cox-2 in HCV-induced pathogenesis

PubMed Central

2011-01-01

Background Hepatitis C virus (HCV) Core protein is thought to trigger activation of multiple signaling pathways and play a significant role in the alteration of cellular gene expression responsible for HCV pathogenesis leading to hepatocellular carcinoma (HCC). However, the exact molecular mechanism of HCV genome specific pathogenesis remains unclear. We examined the in vitro effects of HCV Core protein of HCV genotype 3a and 1a on the cellular genes involved in oxidative stress and angiogenesis. We also studied the ability of HCV Core and Cox-2 siRNA either alone or in combination to inhibit viral replication and cell proliferation in HCV serum infected Huh-7 cells. Results Over expression of Core gene of HCV 3a genotype showed stronger effect in regulating RNA and protein levels of Cox-2, iNOS, VEGF, p-Akt as compared to HCV-1a Core in hepatocellular carcinoma cell line Huh-7 accompanied by enhanced PGE2 release and cell proliferation. We also observed higher expression levels of above genes in HCV 3a patient's blood and biopsy samples. Interestingly, the Core and Cox-2-specific siRNAs down regulated the Core 3a-enhanced expression of Cox-2, iNOS, VEGF, p-Akt. Furthermore, the combined siRNA treatment also showed a dramatic reduction in viral titer and expression of these genes in HCV serum-infected Huh-7 cells. Taken together, these results demonstrated a differential response by HCV 3a genotype in HCV-induced pathogenesis, which may be due to Core and host factor Cox-2 individually or in combination. Conclusions Collectively, these studies not only suggest a genotype-specific interaction between key players of HCV pathogenesis but also may represent combined viral and host gene silencing as a potential therapeutic strategy. PMID:21457561

Expression of cyclooxygenase-1 and cyclooxygenase-2, syndecan-1 and connective tissue growth factor in benign and malignant breast tissue from premenopausal women.

PubMed

Fahlén, M; Zhang, H; Löfgren, L; Masironi, B; von Schoultz, E; von Schoultz, B; Sahlin, L

2017-05-01

Stromal factors have been identified as important for tumorigenesis and metastases of breast cancer. From 49 premenopausal women, samples were collected from benign or malignant tumors and the seemingly normal tissue adjacent to the tumor. The factors studied, with real-time polymerase chain reaction (PCR) and immunohistochemistry, were cyclooxygenase-1 and cyclooxygenase-2 (COX-1 and COX-2), syndecan-1 (S-1) and connective tissue growth factor (CTGF). COX-1 and S-1 mRNA levels were higher in the malignant tumors than in normal and benign tissues. The COX-2 mRNA level was lower in the malignant tumor than in the normal tissue, while CTGF mRNA did not differ between the groups. COX-1 immunostaining was higher in stroma from malignant tumors than in benign tissues, whereas COX-2 immunostaining was higher in the malignant tissue. Glandular S-1 immunostaining was lower in malignant tumors compared to benign and normal tissues, and the opposite was found in stroma. Conclusively, mRNA levels of COX-1 and COX-2 were oppositely regulated, with COX-1 being increased in the malignant tumor while COX-2 was decreased. S-1 protein localization switched from glandular to stromal cells in malignant tissues. Thus, these markers are, in premenopausal women, localized and regulated differently in normal/benign breast tissue as compared to the malignant tumor.

Transcutaneous electrical nerve stimulation attenuates CFA-induced hyperalgesia and inhibits spinal ERK1/2-COX-2 pathway activation in rats

PubMed Central

2013-01-01

Background Transcutaneous electrical nerve stimulation (TENS) is a non-pharmacologic treatment for pain relief. In previous animal studies, TENS effectively alleviated Complete Freund’s Adjuvant (CFA)- or carrageenan-induced inflammatory pain. Although TENS is known to produce analgesia via opioid activation in the brain and at the spinal level, few reports have investigated the signal transduction pathways mediated by TENS. Prior studies have verified the importance of the activation of extracellular signal-regulated kinase (ERK) signal transduction pathway in the spinal cord dorsal horn (SCDH) in acute and persistent inflammatory pains. Here, by using CFA rat model, we tested the efficacy of TENS on inhibiting the expressions of p-ERK1/2 and of its downstream cyclooxygenase-2 (COX-2) and the level of prostaglandin E2 (PGE2) at spinal level. Methods Rats were randomly divided into control, model and TENS groups, and injected subcutaneously with 100 μl CFA or saline in the plantar surface of right hind paw. Rats in the TENS group were treated with TENS (constant aquare wave, 2 Hz and 100 Hz alternating frequencies, intensities ranging from 1 to 2 mA, lasting for 30 min each time) at 5 h and 24 h after injection. Paw withdrawal thresholds (PWTs) were measured with dynamic plantar aesthesiometer at 3d before modeling and 5 h, 6 h, and 25 h after CFA injection. The ipsilateral sides of the lumbar spinal cord dosral horns were harvested for detecting the expressions of p-ERK1/2 and COX-2 by western blot analysis and qPCR, and PGE2 by ELISA. Results CFA-induced periphery inflammation decreased PWTs and increased paw volume of rats. TENS treatment significantly alleviated mechanical hyperalgesia caused by CFA. However, no anti-inflammatory effect of TENS was observed. Expression of p-ERK1/2 protein and COX-2 mRNA was significantly up-regualted at 5 h and 6 h after CFA injection, while COX-2 and PGE2 protein level only increased at 6 h after modeling. Furthermore, the high expression of p-ERK1/2 and COX-2, and over-production of PGE2 induced by CFA, were suppressed by TENS administration. Conclusions TENS may be an effective therapy in controlling inflammatory pain induced by CFA. Its analgesic effect may be associated with the inhibition of activation of the spinal ERK1/2-COX-2 pathway. PMID:23768044

Transcutaneous electrical nerve stimulation attenuates CFA-induced hyperalgesia and inhibits spinal ERK1/2-COX-2 pathway activation in rats.

PubMed

Fang, Jun-Fan; Liang, Yi; Du, Jun-Ying; Fang, Jian-Qiao

2013-06-15

Transcutaneous electrical nerve stimulation (TENS) is a non-pharmacologic treatment for pain relief. In previous animal studies, TENS effectively alleviated Complete Freund's Adjuvant (CFA)- or carrageenan-induced inflammatory pain. Although TENS is known to produce analgesia via opioid activation in the brain and at the spinal level, few reports have investigated the signal transduction pathways mediated by TENS. Prior studies have verified the importance of the activation of extracellular signal-regulated kinase (ERK) signal transduction pathway in the spinal cord dorsal horn (SCDH) in acute and persistent inflammatory pains. Here, by using CFA rat model, we tested the efficacy of TENS on inhibiting the expressions of p-ERK1/2 and of its downstream cyclooxygenase-2 (COX-2) and the level of prostaglandin E2 (PGE2) at spinal level. Rats were randomly divided into control, model and TENS groups, and injected subcutaneously with 100 μl CFA or saline in the plantar surface of right hind paw. Rats in the TENS group were treated with TENS (constant aquare wave, 2 Hz and 100 Hz alternating frequencies, intensities ranging from 1 to 2 mA, lasting for 30 min each time) at 5 h and 24 h after injection. Paw withdrawal thresholds (PWTs) were measured with dynamic plantar aesthesiometer at 3d before modeling and 5 h, 6 h, and 25 h after CFA injection. The ipsilateral sides of the lumbar spinal cord dosral horns were harvested for detecting the expressions of p-ERK1/2 and COX-2 by western blot analysis and qPCR, and PGE2 by ELISA. CFA-induced periphery inflammation decreased PWTs and increased paw volume of rats. TENS treatment significantly alleviated mechanical hyperalgesia caused by CFA. However, no anti-inflammatory effect of TENS was observed. Expression of p-ERK1/2 protein and COX-2 mRNA was significantly up-regualted at 5 h and 6 h after CFA injection, while COX-2 and PGE2 protein level only increased at 6 h after modeling. Furthermore, the high expression of p-ERK1/2 and COX-2, and over-production of PGE2 induced by CFA, were suppressed by TENS administration. TENS may be an effective therapy in controlling inflammatory pain induced by CFA. Its analgesic effect may be associated with the inhibition of activation of the spinal ERK1/2-COX-2 pathway.

Sulforaphane suppresses lipopolysaccharide-induced cyclooxygenase-2 (COX-2) expression through the modulation of multiple targets in COX-2 gene promoter.

PubMed

Woo, Kyung Jin; Kwon, Taeg Kyu

2007-12-15

Sulforaphane is a natural, biologically active compound extracted from cruciferous vegetables such as broccoli and cabbage. It possesses potent anti-inflammation and anti-cancer properties. The mechanism by which sulforaphane suppresses COX-2 expression remains poorly understood. In the present report, we investigated the effect of sulforaphane on the expression of COX-2 in lipopolysaccharide (LPS)-activated Raw 264.7 cells. Sulforaphane significantly suppressed the LPS-induced COX-2 protein and mRNA expression in a dose-dependent manner. The ability of sulforaphane to suppress the expression of the COX-2 was investigated using luciferase reporters controlled by various cis-elements in COX-2 promoter region. Electrophoretic mobility shift assay (EMSA) verified that NF-kappaB, C/EBP, CREB and AP-1 were identified as responsible for the sulforaphane-mediated COX-2 down-regulation. In addition, we demonstrated the signal transduction pathway of mitogen-activated protein kinase (MAP kinase) in LPS-induced COX-2 expression. Taken together, these results demonstrate that sulforaphane effectively suppressed the LPS-induced COX-2 protein via modulation of multiple core promoter elements (NF-kappaB, C/EBP, CREB and AP-1) in the COX-2 transcriptional regulation. These results will provide new insights into the anti-inflammatory and anti-carcinogenic properties of sulforaphane.

COX-2 Expression Correlates With Survival in Patients With Osteosarcoma Lung Metastases

PubMed Central

Rodriguez, Nidra I.; Hoots, William Keith; Koshkina, Nadezhda V.; Morales-Arias, Jaime A.; Arndt, Carola A.; Inwards, Carrie Y.; Hawkins, Douglas S.; Munsell, Mark F.; Kleinerman, Eugenie S.

2009-01-01

Summary The purpose of this study was to determine whether a correlation exists between tumor cyclooxygenase (COX)-2 expression and disease-specific survival in patients with osteosarcoma lung metastases. Thirty-six patients diagnosed with osteosarcoma lung metastases between the years 1990 and 2001 were included in this retrospective study. The majority of the patients (72%) presented newly -diagnosed osteosarcoma lung metastases whereas the remaining patients (28%) presented recurrent disease. Clinicopathologic parameters were obtained from patients’ clinical records. Tissue samples were obtained at the time of resection of the lung metastases and stained for COX-2 using immunohistochemistry. Samples were graded according to the intensity of COX-2 staining (grade 0: negative, grade 1: very weak, grade 2: weak, grade 3: moderate, and grade 4: strong). COX-2 staining was correlated with disease-specific survival and clinicopathologic parameters using the Jonckheere-Terpstra and the Kruskal-Wallis tests. All patients with grade 3 or 4 COX-2 expression died of osteosarcoma lung metastases. Ten percent of patients with grade 2 COX-2 expression and 29% of patients with grade 1 expression were alive and free of disease at the last follow-up. By contrast, 60% of the patients with grade 0 COX-2 expression were alive and free of disease at the last follow-up. No association between COX-2 expression and clinicopathologic parameters was found. However, COX-2 expression correlated inversely with disease-specific survival in patients with osteosarcoma lung metastases. Our data indicate that COX-2 expression in metastatic osteosarcoma may have prognostic significance. PMID:18797196

Hypomethylation of inflammatory genes (COX2, EGR1, and SOCS3) and increased urinary 8-nitroguanine in arsenic-exposed newborns and children

DOE Office of Scientific and Technical Information (OSTI.GOV)

Phookphan, Preeyaphan; Navasumrit, Panida

Early-life exposure to arsenic increases risk of developing a variety of non-malignant and malignant diseases. Arsenic-induced carcinogenesis may be mediated through epigenetic mechanisms and pathways leading to inflammation. Our previous study reported that prenatal arsenic exposure leads to increased mRNA expression of several genes related to inflammation, including COX2, EGR1, and SOCS3. This study aimed to investigate the effects of arsenic exposure on promoter DNA methylation and mRNA expression of these inflammatory genes (COX2, EGR1, and SOCS3), as well as the generation of 8-nitroguanine, which is a mutagenic DNA lesion involved in inflammation-related carcinogenesis. Prenatally arsenic-exposed newborns had promoter hypomethylationmore » of COX2, EGR1, and SOCS3 in cord blood lymphocytes (p < 0.01). A follow-up study in these prenatally arsenic-exposed children showed a significant hypomethylation of these genes in salivary DNA (p < 0.01). In vitro experiments confirmed that arsenite treatment at short-term high doses (10–100 μM) and long-term low doses (0.5–1 μM) in human lymphoblasts (RPMI 1788) caused promoter hypomethylation of these genes, which was in concordance with an increase in their mRNA expression. Additionally, the level of urinary 8-nitroguanine was significantly higher (p < 0.01) in exposed newborns and children, by 1.4- and 1.8-fold, respectively. Arsenic accumulation in toenails was negatively correlated with hypomethylation of these genes and positively correlated with levels of 8-nitroguanine. These results indicated that early-life exposure to arsenic causes hypomethylation of COX2, EGR1, and SOCS3, increases mRNA expression of these genes, and increases 8-nitroguanine formation. These effects may be linked to mechanisms of arsenic-induced inflammation and cancer development later in life. - Highlight: • Early-life arsenic exposure caused promoter hypomethylation of COX2, EGR1 and SOCS3. • Hypomethylation of these genes is associated with increased mRNA expression. • Arsenite treatment in vitro showed hypomethylation and increased mRNA expression. • Arsenic-exposed newborns and children had higher levels of urinary 8-nitroguanine. • Urinary 8-nitroguanine correlated with hypomethylation and mRNA expression.« less

COX-2 verexpression in pretreatment biopsies predicts response of rectal cancers to neoadjuvant radiochemotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, Fraser M.; Reynolds, John V.; Kay, Elaine W.

2006-02-01

Purpose: To determine the utility of COX-2 expression as a response predictor for patients with rectal cancer who are undergoing neoadjuvant radiochemotherapy (RCT). Methods and Materials: Pretreatment biopsies (PTB) from 49 patients who underwent RCT were included. COX-2 and proliferation in PTB were assessed by immunohistochemistry (IHC) and apoptosis was detected by TUNEL stain. Response to treatment was assessed by a 5-point tumor-regression grade (TRG) based on the ratio of residual tumor to fibrosis. Results: Good response (TRG 1 + 2), moderate response (TRG 3), and poor response (TRG 4 + 5) were seen in 21 patients (42%), 11 patientsmore » (22%), and 17 patients (34%), respectively. Patients with COX-2 overexpression in PTB were more likely to demonstrate moderate or poor response (TRG 3 + 4) to treatment than were those with normal COX-2 expression (p = 0.026, chi-square test). Similarly, poor response was more likely if patients had low levels of spontaneous apoptosis in PTBs (p = 0.0007, chi-square test). Conclusions: COX-2 overexpression and reduced apoptosis in PTB can predict poor response of rectal cancer to RCT. As COX-2 inhibitors are commercially available, their administration to patients who overexpress COX-2 warrants assessment in clinical trials in an attempt to increase overall response rates.« less

Modulation of Cytokine-Induced Cyclooxygenase 2 Expression by PPARG Ligands Through NFκB Signal Disruption in Human WISH and Amnion Cells1

PubMed Central

Ackerman, William E.; Zhang, Xiaolan L.; Rovin, Brad H.; Kniss, Douglas A.

2006-01-01

Cyclooxygenase (COX) activity increases in the human amnion in the settings of term and idiopathic preterm labor, contributing to the generation of uterotonic prostaglandins (PGs) known to participate in mammalian parturition. Augmented COX activity is highly correlated with increased COX2 (also known as prostaglandin-endoperoxide synthase 2, PTGS2) gene expression. We and others have demonstrated an essential role for nuclear factor κB (NFκB) in cytokine-driven COX2 expression. Peroxisome proliferator-activated receptor gamma (PPARG), a member of the nuclear hormone receptor superfamily, has been shown to antagonize NFκB activation and inflammatory gene expression, including COX2. We hypothesized that PPARG activation might suppress COX2 expression during pregnancy. Using primary amnion and WISH cells, we evaluated the effects of pharmacological (thiazolidinediones) and putative endogenous (15-deoxy-Δ12,14-prostaglandin J2, 15d-PGJ2) PPARG ligands on cytokine-induced NFκB activation, COX2 expression, and PGE2 production. We observed that COX2 expression and PGE2 production induced by tumor necrosis factor alpha (TNF) were significantly abrogated by 15d-PGJ2. The thiazolidinediones rosiglitazone (ROSI) and troglitazone (TRO) had relatively little effect on cytokine-induced COX2 expression except at high concentrations, at which these agents tended to increase COX2 abundance relative to cells treated with TNF alone. Interestingly, treatment with ROSI, but not TRO, led to augmentation of TNF-stimulated PGE2 production. Mechanistically, we observed that 15d-PGJ2 markedly diminished cytokine-induced activity of the NFκB transcription factor, whereas thiazolidinediones had no discernable effect on this system. Our data suggest that pharmacological and endogenous PPARG ligands use both receptor-dependent and -independent mechanisms to influence COX2 expression. PMID:15843495

The low molecular weight fraction of human serum albumin upregulates COX2, prostaglandin E2, and prostaglandin D2 under inflammatory conditions in osteoarthritic knee synovial fibroblasts.

PubMed

Frederick, Elizabeth D; Hausburg, Melissa A; Thomas, Gregory W; Rael, Leonard T; Brody, Edward; Bar-Or, David

2016-12-01

The ability to decrease inflammation and promote healing is important in the intervention and management of a variety of disease states, including osteoarthritis of the knee (OAK). Even though cyclooxygenase 2 (COX2) has an established pro-inflammatory role, evidence suggests it is also critical to the resolution that occurs after the initial activation phase of the immune response. In this study, we investigated the effects of the low molecular weight fraction of 5% human serum albumin (LMWF-5A), an agent that has proven to decrease pain and improve function in OAK patients after intra-articular injection, on the expression of COX2 and its downstream products, prostaglandins (PGs). Fibroblast-like synoviocytes from the synovial membrane of OAK patients were treated with LMWF-5A or saline as a control with or without the addition of interleukin-1β (IL-1β) or tumor necrosis factor α (TNFα) to elicit an inflammatory response. Cells were harvested for RNA and protein at 2, 4, 8, 12, and 24 h, and media was collected at 24 h for analysis of secreted products. COX2 mRNA expression was determined by qPCR, and COX2 protein expression was determined by western blot analysis. Levels of prostaglandin E2 (PGE2) and prostaglandin D2 (PGD2) in the media were quantified by competitive ELISA. In the presence of either IL-1β or TNFα, LMWF-5A increased the expression of both COX2 mRNA and protein, and this increase was significant compared to that observed with IL-1β- or TNFα-stimulated, saline-treated cells. Downstream of COX2, the levels of PGE2 were increased only in TNFα-stimulated, LMWF-5A-treated cells; however, in both IL-1β- and TNFα-stimulated cells, LMWF-5A increased the release of the anti-inflammatory prostaglandin PGD2. LMWF-5A appears to trigger increased anti-inflammatory PG signaling, and this may be a primary component of its therapeutic mode of action in the treatment of OAK.

In vitro anti-inflammatory effects of arctigenin, a lignan from Arctium lappa L., through inhibition on iNOS pathway.

PubMed

Zhao, Feng; Wang, Lu; Liu, Ke

2009-04-21

Arctigenin, a bioactive constituent from dried seeds of Arctium lappa L. (Compositae) which has been widely used as a Traditional Chinese Medicine for dispelling wind and heat included in Chinese Pharmacophere, was found to exhibit anti-inflammatory activities but its molecular mechanism remains unknown yet. To investigate the anti-inflammatory mechanism of arctigenin. Cultured macrophage RAW 264.7 cells and THP-1 cells were used for the experiments. Griess assay was used to evaluate the inhibitory effect of arctigenin on the overproduction of nitric oxide (NO). ELISA was used to determine the level of pro-inflammatory cytokines including tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6). The inhibitory effect on the enzymatic activity of cyclooxygenase-2 (COX-2) was tested by colorimetric method. Western blot was used to detect the expression of inducible nitric oxide synthase (iNOS) and COX-2. Arctigenin suppressed lipopolysaccharide (LPS)-stimulated NO production and pro-inflammatory cytokines secretion, including TNF-alpha and IL-6 in a dose-dependent manner. Arctigenin also strongly inhibited the expression of iNOS and iNOS enzymatic activity, whereas the expression of COX-2 and COX-2 enzymatic activity were not affected by arctigenin. These results indicated that potent inhibition on NO, TNF-alpha and IL-6, but not COX-2 expression and COX-2 activity, might constitute the anti-inflammatory mechanism of arctigenin. Arctigenin suppressed the overproduction of NO through down-regulation of iNOS expression and iNOS enzymatic activity in LPS-stimulated macrophage.

COX-2 overexpression in resected pancreatic head adenocarcinomas correlates with favourable prognosis

PubMed Central

2014-01-01

Background Overexpression of cyclooxygenase-2 (COX-2) has been implicated in oncogenesis and progression of adenocarcinomas of the pancreatic head. The data on the prognostic importance of COX expression in these tumours is inconsistent and conflicting. We evaluated how COX-2 overexpression affected overall postoperative survival in pancreatic head adenocarcinomas. Methods The study included 230 consecutive pancreatoduodenectomies for pancreatic cancer (PC, n = 92), ampullary cancer (AC, n = 62) and distal bile duct cancer (DBC, n = 76). COX-2 expression was assessed by immunohistochemistry. Associations between COX-2 expression and histopathologic variables including degree of differentiation, histopathologic type of differentiation (pancreatobiliary vs. intestinal) and lymph node ratio (LNR) were evaluated. Unadjusted and adjusted survival analysis was performed. Results COX-2 staining was positive in 71% of PC, 77% in AC and 72% in DBC. Irrespective of tumour origin, overall patient survival was more favourable in patients with COX-2 positive tumours than COX-2 negative (p = 0.043 in PC, p = 0.011 in AC, p = 0.06 in DBC). In tumours of pancreatobiliary type of histopathological differentiation, COX-2 expression did not significantly affect overall patient survival. In AC with intestinal differentiation COX-2 expression significantly predicted favourable survival (p = 0.003). In PC, COX-2 expression was significantly associated with high degree of differentiation (p = 0.002). COX-2 and LNR independently predicted good prognosis in a multivariate model. Conclusions COX-2 is overexpressed in pancreatic cancer, ampullary cancer and distal bile duct cancer and confers a survival benefit in all three cancer types. In pancreatic cancer, COX-2 overexpression is significantly associated with the degree of differentiation and independently predicts a favourable prognosis. PMID:24950702

Lactoferrin from Camelus dromedarius Inhibits Nuclear Transcription Factor-kappa B Activation, Cyclooxygenase-2 Expression and Prostaglandin E2 Production in Stimulated Human Chondrocytes

PubMed Central

Rasheed, Naila; Alghasham, Abdullah; Rasheed, Zafar

2016-01-01

Background: Osteoarthritis (OA) is a progressive joint disorder, which remains the leading cause of chronic disability in aged people. Nuclear factor-kappa B (NF)-κB is a major cellular event in OA and its activation by interleukin-1β (IL-1β) plays a critical role in cartilage breakdown in these patients. Objective: In this study, we examined the effect of lactoferrin on NF-κB activation, cyclooxygenase-2 (COX-2) expression and prostaglandin E2 (PGE2) production in stimulated human articular chondrocytes. Materials and Methods: Human chondrocytes were derived from OA articular cartilage and treated with camel lactoferrin and then stimulated with IL-1β. Gene expression was determined by TaqMan assays and protein expression was studied by Western immunoblotting. NF-κB activity and PGE2 levels were determined by ELISA based assays. NF-κB activity was also determined by treatment of chondrocytes with NF-κB specific inhibitor Bay 11–7082. Results: Lactoferrin inhibited IL-1β-induced activation and nuclear translocation of NF-κB p65 in human OA chondrocytes. Lactoferrin also inhibited mRNA/protein expression of COX-2 and production of PGE2. Moreover, Bay 11–7082 also inhibited IL-1β-induced expression of COX-2 and production of PGE2. The inhibitory effect of lactoferrin on the IL-1β induced expression of COX-2 or production of PGE2 was mediated at least in part via suppression of NF-κB activation. Conclusions: Our data determine camel lactoferrin as a novel inhibitor of IL-1β-induced activation of NF-κB signaling events and production of cartilage-degrading molecule PGE2 via inhibition of COX-2 expressions. These results may have important implications for the development of novel therapeutic strategies for the prevention/treatment of OA and other degenerative/inflammatory diseases. SUMMARY Lactoferrin shows anti-arthritic activity in IL-1β stimulated primary human chondrocytes.Lactoferrin inhibits IL-1β-induced NF-κB activation.Lactoferrin inhibits production of cartilage degrading PGE2 via inhibition of COX-2 expression. Abbreviations Used: OA: Osteoarthritis IL-1β: Interleukin-1 beta NF-κB: Nuclear factor-kappa B COX-2: cyclooxygenase-2 PGE2: prostaglandin E2 PMID:27034605

Lactoferrin from Camelus dromedarius Inhibits Nuclear Transcription Factor-kappa B Activation, Cyclooxygenase-2 Expression and Prostaglandin E2 Production in Stimulated Human Chondrocytes.

PubMed

Rasheed, Naila; Alghasham, Abdullah; Rasheed, Zafar

2016-01-01

Osteoarthritis (OA) is a progressive joint disorder, which remains the leading cause of chronic disability in aged people. Nuclear factor-kappa B (NF)-κB is a major cellular event in OA and its activation by interleukin-1β (IL-1β) plays a critical role in cartilage breakdown in these patients. In this study, we examined the effect of lactoferrin on NF-κB activation, cyclooxygenase-2 (COX-2) expression and prostaglandin E2 (PGE2) production in stimulated human articular chondrocytes. Human chondrocytes were derived from OA articular cartilage and treated with camel lactoferrin and then stimulated with IL-1β. Gene expression was determined by TaqMan assays and protein expression was studied by Western immunoblotting. NF-κB activity and PGE2 levels were determined by ELISA based assays. NF-κB activity was also determined by treatment of chondrocytes with NF-κB specific inhibitor Bay 11-7082. Lactoferrin inhibited IL-1β-induced activation and nuclear translocation of NF-κB p65 in human OA chondrocytes. Lactoferrin also inhibited mRNA/protein expression of COX-2 and production of PGE2. Moreover, Bay 11-7082 also inhibited IL-1β-induced expression of COX-2 and production of PGE2. The inhibitory effect of lactoferrin on the IL-1β induced expression of COX-2 or production of PGE2 was mediated at least in part via suppression of NF-κB activation. Our data determine camel lactoferrin as a novel inhibitor of IL-1β-induced activation of NF-κB signaling events and production of cartilage-degrading molecule PGE2 via inhibition of COX-2 expressions. These results may have important implications for the development of novel therapeutic strategies for the prevention/treatment of OA and other degenerative/inflammatory diseases. Lactoferrin shows anti-arthritic activity in IL-1β stimulated primary human chondrocytes.Lactoferrin inhibits IL-1β-induced NF-κB activation.Lactoferrin inhibits production of cartilage degrading PGE2 via inhibition of COX-2 expression. Abbreviations Used: OA: Osteoarthritis IL-1β: Interleukin-1 beta NF-κB: Nuclear factor-kappa B COX-2: cyclooxygenase-2 PGE2: prostaglandin E2.

XRCC5 cooperates with p300 to promote cyclooxygenase-2 expression and tumor growth in colon cancers

PubMed Central

Hao, Jiajiao; Chen, Miao; Yu, Wendan; Guo, Wei; Chen, Yiming; Huang, Wenlin; Deng, Wuguo

2017-01-01

Cyclooxygenase (COX) is the rate-limiting enzyme in prostaglandins (PGs) biosynthesis. Previous studies indicate that COX-2, one of the isoforms of COX, is highly expressed in colon cancers and plays a key role in colon cancer carcinogenesis. Thus, searching for novel transcription factors regulating COX-2 expression will facilitate drug development for colon cancer. In this study, we identified XRCC5 as a binding protein of the COX-2 gene promoter in colon cancer cells with streptavidin-agarose pulldown assay and mass spectrometry analysis, and found that XRCC5 promoted colon cancer growth through modulation of COX-2 signaling. Knockdown of XRCC5 by siRNAs inhibited the growth of colon cancer cells in vitro and of tumor xenografts in a mouse model in vivo by suppressing COX-2 promoter activity and COX-2 protein expression. Conversely, overexpression of XRCC5 promoted the growth of colon cancer cells by activating COX-2 promoter and increasing COX-2 protein expression. Moreover, the role of p300 (a transcription co-activator) in acetylating XRCC5 to co-regulate COX-2 expression was also evaluated. Immunofluorescence assay and confocal microscopy showed that XRCC5 and p300 proteins were co-located in the nucleus of colon cancer cells. Co-immunoprecipitation assay also proved the interaction between XRCC5 and p300 in nuclear proteins of colon cancer cells. Cell viability assay indicated that the overexpression of wild-type p300, but not its histone acetyltransferase (HAT) domain deletion mutant, increased XRCC5 acetylation, thereby up-regulated COX-2 expression and promoted the growth of colon cancer cells. In contrast, suppression of p300 by a p300 HAT-specific inhibitor (C646) inhibited colon cancer cell growth by suppressing COX-2 expression. Taken together, our results demonstrated that XRCC5 promoted colon cancer growth by cooperating with p300 to regulate COX-2 expression, and suggested that the XRCC5/p300/COX-2 signaling pathway was a potential target in the treatment of colon cancers. PMID:29049411

Immunohistochemical and morphometric evaluation of COX-1 and COX-2 in the remodeled lung in idiopathic pulmonary fibrosis and systemic sclerosis* ,**

PubMed Central

Parra, Edwin Roger; Lin, Flavia; Martins, Vanessa; Rangel, Maristela Peres; Capelozzi, Vera Luiza

2013-01-01

OBJECTIVE: To study the expression of COX-1 and COX-2 in the remodeled lung in systemic sclerosis (SSc) and idiopathic pulmonary fibrosis (IPF) patients, correlating that expression with patient survival. METHODS: We examined open lung biopsy specimens from 24 SSc patients and 30 IPF patients, using normal lung tissue as a control. The histological patterns included fibrotic nonspecific interstitial pneumonia (NSIP) in SSc patients and usual interstitial pneumonia (UIP) in IPF patients. We used immunohistochemistry and histomorphometry to evaluate the expression of COX-1 and COX-2 in alveolar septa, vessels, and bronchioles. We then correlated that expression with pulmonary function test results and evaluated its impact on patient survival. RESULTS: The expression of COX-1 and COX-2 in alveolar septa was significantly higher in IPF-UIP and SSc-NSIP lung tissue than in the control tissue. No difference was found between IPF-UIP and SSc-NSIP tissue regarding COX-1 and COX-2 expression. Multivariate analysis based on the Cox regression model showed that the factors associated with a low risk of death were younger age, high DLCO/alveolar volume, IPF, and high COX-1 expression in alveolar septa, whereas those associated with a high risk of death were advanced age, low DLCO/alveolar volume, SSc (with NSIP), and low COX-1 expression in alveolar septa. CONCLUSIONS: Our findings suggest that strategies aimed at preventing low COX-1 synthesis will have a greater impact on SSc, whereas those aimed at preventing high COX-2 synthesis will have a greater impact on IPF. However, prospective randomized clinical trials are needed in order to confirm that. PMID:24473763

Microarray analysis of gene expression in the cyclooxygenase knockout mice - a connection to autism spectrum disorder.

PubMed

Rai-Bhogal, Ravneet; Ahmad, Eizaaz; Li, Hongyan; Crawford, Dorota A

2018-03-01

The cellular and molecular events that take place during brain development play an important role in governing function of the mature brain. Lipid-signalling molecules such as prostaglandin E 2 (PGE 2 ) play an important role in healthy brain development. Abnormalities along the COX-PGE 2 signalling pathway due to genetic or environmental causes have been linked to autism spectrum disorder (ASD). This study aims to evaluate the effect of altered COX-PGE 2 signalling on development and function of the prenatal brain using male mice lacking cyclooxygenase-1 and cyclooxygenase-2 (COX-1 -/- and COX-2 -/- ) as potential model systems of ASD. Microarray analysis was used to determine global changes in gene expression during embryonic days 16 (E16) and 19 (E19). Gene Ontology: Biological Process (GO:BP) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were implemented to identify affected developmental genes and cellular processes. We found that in both knockouts the brain at E16 had nearly twice as many differentially expressed genes, and affected biological pathways containing various ASD-associated genes important in neuronal function. Interestingly, using GeneMANIA and Cytoscape we also show that the ASD-risk genes identified in both COX-1 -/- and COX-2 -/- models belong to protein-interaction networks important for brain development despite of different cellular localization of these enzymes. Lastly, we identified eight genes that belong to the Wnt signalling pathways exclusively in the COX-2 -/- mice at E16. The level of PKA-phosphorylated β-catenin (S552), a major activator of the Wnt pathway, was increased in this model, suggesting crosstalk between the COX-2-PGE 2 and Wnt pathways during early brain development. Overall, these results provide further molecular insight into the contribution of the COX-PGE 2 pathways to ASD and demonstrate that COX-1 -/- and COX-2 -/- animals might be suitable new model systems for studying the disorders. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Carbon Monoxide (CO) Released from Tricarbonyldichlororuthenium (II) Dimer (CORM-2) in Gastroprotection against Experimental Ethanol-Induced Gastric Damage.

PubMed

Magierowska, Katarzyna; Magierowski, Marcin; Hubalewska-Mazgaj, Magdalena; Adamski, Juliusz; Surmiak, Marcin; Sliwowski, Zbigniew; Kwiecien, Slawomir; Brzozowski, Tomasz

2015-01-01

The physiological gaseous molecule, carbon monoxide (CO) becomes a subject of extensive investigation due to its vasoactive activity throughout the body but its role in gastroprotection has been little investigated. We determined the mechanism of CO released from its donor tricarbonyldichlororuthenium (II) dimer (CORM-2) in protection of gastric mucosa against 75% ethanol-induced injury. Rats were pretreated with CORM-2 30 min prior to 75% ethanol with or without 1) non-selective (indomethacin) or selective cyclooxygenase (COX)-1 (SC-560) and COX-2 (celecoxib) inhibitors, 2) nitric oxide (NO) synthase inhibitor L-NNA, 3) ODQ, a soluble guanylyl cyclase (sGC) inhibitor, hemin, a heme oxygenase (HO)-1 inductor or zinc protoporphyrin IX (ZnPPIX), an inhibitor of HO-1 activity. The CO content in gastric mucosa and carboxyhemoglobin (COHb) level in blood was analyzed by gas chromatography. The gastric mucosal mRNA expression for HO-1, COX-1, COX-2, iNOS, IL-4, IL-1β was analyzed by real-time PCR while HO-1, HO-2 and Nrf2 protein expression was determined by Western Blot. Pretreatment with CORM-2 (0.5-10 mg/kg) dose-dependently attenuated ethanol-induced lesions and raised gastric blood flow (GBF) but large dose of 100 mg/kg was ineffective. CORM-2 (5 mg/kg and 50 mg/kg i.g.) significantly increased gastric mucosal CO content and whole blood COHb level. CORM-2-induced protection was reversed by indomethacin, SC-560 and significantly attenuated by celecoxib, ODQ and L-NNA. Hemin significantly reduced ethanol damage and raised GBF while ZnPPIX which exacerbated ethanol-induced injury inhibited CORM-2- and hemin-induced gastroprotection and the accompanying rise in GBF. CORM-2 significantly increased gastric mucosal HO-1 mRNA expression and decreased mRNA expression for iNOS, IL-1β, COX-1 and COX-2 but failed to affect HO-1 and Nrf2 protein expression decreased by ethanol. We conclude that CORM-2 released CO exerts gastroprotection against ethanol-induced gastric lesions involving an increase in gastric microcirculation mediated by sGC/cGMP, prostaglandins derived from COX-1, NO-NOS system and its anti-inflammatory properties.

Cyclooxygenase-2 expression after preoperative chemoradiotherapy correlates with more frequent esophageal cancer recurrence

PubMed Central

Yoshikawa, Reigetsu; Fujiwara, Yoshinori; Koishi, Kenji; Kojima, Syoudou; Matsumoto, Tomohiro; Yanagi, Hidenori; Yamamura, Takehira; Hashimoto-Tamaoki, Tomoko; Nishigami, Takashi; Tsujimura, Tohru

2007-01-01

AIM: To investigate the relationship between cycloo-xygenase-2 (COX-2), and vascular endothelial growth factor (VEGF), and to determine the clinical significance of this relationship in esophageal cancer patients undergoing chemoradiotherapy (CRT). METHODS: Immunohistochemical staining was used to evaluate COX-2 and VEGF expression in 40 patients with histologically-confirmed esophageal squamous carcinoma (ESCC) who were undergoing preoperative CRT. RESULTS: Fourteen out of 40 ESCC patients showed a pathological complete response (CR) after CRT. COX-2 and VEGF protein expressions were observed in the cytoplasm of 17 and 13 tumors, respectively, with null expression in 9 and 13 tumors, respectively. COX-2 expression was strongly correlated with VEGF expression (P < 0.05). There were also significant associations between COX-2 expression, tumor recurrence, and lymph-node involvement (P = 0.0277 and P = 0.0095, respectively). COX-2 expression and VEGF expression had significant prognostic value for disease-free survival (log-rank test; P = 0.0073 and P = 0.0341, respectively), but not for overall survival, as assessed by univariate analysis. CONCLUSION: Our results suggest that COX-2 expression correlates with VEGF expression and might be a useful prognostic factor for more frequent tumor recurrence in ESCC patients undergoing neoadjuvant CRT. These findings support the use of anti-angiogenic COX-2 inhibitors in the treatment of ESCC. PMID:17511025

Expression of cyclooxygenase-1 and -2 in canine nasal carcinomas.

PubMed

Borzacchiello, G; Paciello, O; Papparella, S

2004-07-01

Cyclooxygenase-1 (COX-1) and cyclooxygenase -2 (COX-2) are known to play a role in the carcinogenesis of many human and animal primary epithelial tumours. However, expression of COX-1 and -2 has not been investigated in canine nasal epithelial carcinoma, a rare form of neoplasia. COX-1 immunolabelling was demonstrated in normal canine nasal mucosa and in a minority of neoplastic specimens. Cytoplasmic COX-2, however, was strongly expressed in the majority of canine nasal carcinomas. In addition, COX-2 expression was demonstrated in dysplastic epithelium and in a proportion of stromal cells. Co-expression of both enzyme isoforms was revealed by confocal laser scanning microscopy. The results indicate that COX-2 is overexpressed in a proportion of naturally occurring canine nasal carcinomas, suggesting its possible role in canine nasal tumorigenesis. Copyright 2004 Elsevier Ltd.

COX-1 vs. COX-2 as a determinant of basal tone in the internal anal sphincter

PubMed Central

de Godoy, Márcio A. F.; Rattan, Neeru; Rattan, Satish

2009-01-01

Prostanoids, produced endogenously via cyclooxygenases (COXs), have been implicated in the sustained contraction of different smooth muscles. The two major types of COXs are COX-1 and COX-2. The COX subtype involved in the basal state of the internal anal sphincter (IAS) smooth muscle tone is not known. To identify the COX subtype, we examined the effect of COX-1- and COX-2-selective inhibitors, SC-560 and rofecoxib, respectively, on basal tone in the rat IAS. We also determined the effect of selective deletion of COX-1 and COX-2 genes (COX-1−/− and COX-2−/− mice) on basal tone in murine IAS. Our data show that SC-560 causes significantly more efficacious and potent concentration-dependent decreases in IAS tone than rofecoxib. In support of these data, significantly higher levels of COX-1 than COX-2 mRNA were found in the IAS. In addition, higher levels of COX-1 mRNA and protein were expressed in rat IAS than rectal smooth muscle. In wild-type mice, IAS tone was decreased 41.4 ± 3.4% (mean ± SE) by SC-560 (1 × 10−5 M) and 5.4 ± 2.2% by rofecoxib (P < 0.05, n = 5). Basal tone was 0.172 ± 0.021 mN//mg in the IAS from wild-type mice and significantly less (0.080 ± 0.015 mN/mg) in the IAS from COX-1−/− mice (P < 0.05, n = 5). However, basal tone in COX-2−/− mice was not significantly different from that in wild-type mice. We conclude that COX-1-related products contribute significantly to IAS tone. PMID:19056763

COX-1 vs. COX-2 as a determinant of basal tone in the internal anal sphincter.

PubMed

de Godoy, Márcio A F; Rattan, Neeru; Rattan, Satish

2009-02-01

Prostanoids, produced endogenously via cyclooxygenases (COXs), have been implicated in the sustained contraction of different smooth muscles. The two major types of COXs are COX-1 and COX-2. The COX subtype involved in the basal state of the internal anal sphincter (IAS) smooth muscle tone is not known. To identify the COX subtype, we examined the effect of COX-1- and COX-2-selective inhibitors, SC-560 and rofecoxib, respectively, on basal tone in the rat IAS. We also determined the effect of selective deletion of COX-1 and COX-2 genes (COX-1(-/-) and COX-2(-/-) mice) on basal tone in murine IAS. Our data show that SC-560 causes significantly more efficacious and potent concentration-dependent decreases in IAS tone than rofecoxib. In support of these data, significantly higher levels of COX-1 than COX-2 mRNA were found in the IAS. In addition, higher levels of COX-1 mRNA and protein were expressed in rat IAS than rectal smooth muscle. In wild-type mice, IAS tone was decreased 41.4 +/- 3.4% (mean +/- SE) by SC-560 (1 x 10(-5) M) and 5.4 +/- 2.2% by rofecoxib (P < 0.05, n = 5). Basal tone was 0.172 +/- 0.021 mN//mg in the IAS from wild-type mice and significantly less (0.080 +/- 0.015 mN/mg) in the IAS from COX-1(-/-) mice (P < 0.05, n = 5). However, basal tone in COX-2(-/-) mice was not significantly different from that in wild-type mice. We conclude that COX-1-related products contribute significantly to IAS tone.

Evaluation of guggulipid and nimesulide on production of inflammatory mediators and GFAP expression in LPS stimulated rat astrocytoma, cell line (C6).

PubMed

Niranjan, Rituraj; Kamat, Pradeep Kumar; Nath, Chandishwar; Shukla, Rakesh

2010-02-17

The present study was designed to investigate effect of guggulipid, a drug developed by CDRI and nimesulide on LPS stimulated neuroinflammatory changes in rat astrocytoma cell line (C6). Rat astrocytoma cells (C6) were stimulated with LPS (10 microg/ml) alone and in combinations with different concentrations of guggulipid or nimesulide for 24h of incubation. Nitrite release in culture supernatant, ROS in cells, expressions of COX-2, GFAP and TNF-alpha in cell lysate were estimated. LPS (10 microg/ml) stimulated C6 cells to release nitrite, ROS generation, up regulated COX-2 and GFAP expressions at protein level and TNF-alpha at mRNA level. Both guggulipid and nimesulide significantly attenuated nitrite release, ROS generation and also down regulated expressions of COX-2, GFAP and TNF-alpha. Guggulipid and nimesulide per se did not have any significant effect on C6 cells. Results demonstrate the anti-inflammatory effect of guggulipid comparable to nimesulide which suggest potential use of guggulipid in neuroinflammation associated conditions in CNS disorders. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

Involvement of COX-2 in nickel elution from a wire implanted subcutaneously in mice.

PubMed

Sato, Taiki; Kishimoto, Yu; Asakawa, Sanki; Mizuno, Natsumi; Hiratsuka, Masahiro; Hirasawa, Noriyasu

2016-07-01

Many types of medical alloys include nickel (Ni), and the elution of Ni ions from these materials causes toxicities and inflammation. We have previously reported that inflammation enhances Ni elution, although the molecular mechanisms underlying this effect remain unclear. In this study, we investigated how inflammatory responses enhanced Ni elution in a wire-implantation mouse model. Subcutaneous implantation of Ni wire induced the expression of cyclooxygenase-2 (COX-2) and microsomal prostaglandin E synthase-1 (mPGES-1) mRNA in the surrounding tissues. Immunostaining analysis showed that cells expressing COX-2 were mainly fibroblast-like cells 8h after implantation of a Ni wire, but were mainly infiltrated leukocytes at 24h. NiCl2 induced the expression of COX-2 mRNA in primary fibroblasts, neutrophils, RAW 264 cells, and THP-1 cells, indicating that Ni ions can induce COX-2 expression in various types of cells. The elution of Ni ions from the implanted Ni wire at 8h was reduced by dexamethasone (Dex), indomethacin (Ind), or celecoxib (Cel) treatment. Ni wire implantation induced an increase in mRNA levels for anaerobic glycolytic pathway components glucose transporter 1 (GLUT1), hexokinase 2 (HK2), lactate dehydrogenase A (LDHA), and monocarboxylate transporter 4 (MCT4); the expression of these genes was also inhibited by Dex, Ind, and Cel. In primary fibroblasts, the expression of these mRNAs and the production of lactate were induced by NiCl2 and further potentiated by PGE2. Furthermore, Ni wire-induced infiltration of inflammatory leukocytes was significantly reduced by Dex, Ind, or Cel. Depletion of neutrophils with a specific antibody caused reduction of both leukocyte infiltration and Ni elution. These results indicate that Ni ions eluted from wire induced COX-2 expression, which further promoted elution of Ni ions by increasing lactate production and leukocyte infiltration. Since COX inhibitors and Dex reduced the elution of Ni ions, these drugs may be useful for prevention of metal-related inflammation and allergy. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Are there attacking points in the eicosanoid cascade for chemotherapeutic options in benign meningiomas?

PubMed

Pfister, Christina; Ritz, Rainer; Pfrommer, Heike; Bornemann, Antje; Tatagiba, Marcos S; Roser, Florian

2007-01-01

The current treatment for recurrent or malignant meningiomas with adjuvant therapies has not been satisfactory, and there is an intense interest in evaluating new molecular markers to act as therapeutic targets. Enzymes of the arachidonic acid (AA) cascade such as cyclooxygenase (COX)-2 or 5-lipoxygenase (5-LO) are upregulated in a number of epithelial tumors, but to date there are hardly any data about the expression of these markers in meningiomas. To find possible targets for chemotherapeutic intervention, the authors evaluated the expression of AA derivatives at different molecular levels in meningiomas. One hundred and twenty-four meningioma surgical specimens and normal human cortical tissue samples were immunohistochemically and cytochemically stained for COX-2, COX-1, 5-LO, and prostaglandin E receptor 4 (PTGER4). In addition, Western blot and polymerase chain reaction (PCR) analyses were performed to detect the presence of eicosanoids in vivo and in vitro. Sixty (63%) of 95 benign meningiomas, 21 (88%) of 24 atypical meningiomas, all five malignant meningiomas, and all normal human cortex samples displayed high COX-2 immunoreactivity. All cultured specimens and IOMM-Lee cells stained positive for COX-2, COX-1, 5-LO, and PTGER4. The PCR analysis demonstrated no changes in eicosanoid expression among meningiomas of different World Health Organization grades and in normal human cortical and dura mater tissue. Eicosanoid derivatives COX-1, COX-2, 5-LO, and PTGER4 enzymes show a high universal expression in meningiomas but are not upregulated in normal human cortex and dura tissue. This finding of the ubiquitous presence of these enzymes in meningiomas offers an excellent baseline for testing upcoming chemotherapeutic treatments.

n-Hexane Insoluble Fraction of Plantago lanceolata Exerts Anti-Inflammatory Activity in Mice by Inhibiting Cyclooxygenase-2 and Reducing Chemokines Levels.

PubMed

Fakhrudin, Nanang; Dwi Astuti, Eny; Sulistyawati, Rini; Santosa, Djoko; Susandarini, Ratna; Nurrochmad, Arief; Wahyuono, Subagus

2017-03-13

Inflammation is involved in the progression of many disorders, such as tumors, arthritis, gastritis, and atherosclerosis. Thus, the development of new agents targeting inflammation is still challenging. Medicinal plants have been used traditionally to treat various diseases including inflammation. A previous study has indicated that dichloromethane extract of P. lanceolata leaves exerts anti-inflammatory activity in an in vitro model. Here, we examined the in vivo anti-inflammatory activities of a n -hexane insoluble fraction of P. lanceolata leaves dichloromethane extract (HIFPL). We first evaluated its potency to reduce paw edema induced by carrageenan, and the expression of the proinflammatory enzyme, cyclooxygenase (COX)-2, in mice. The efficacy of HIFPL to inhibit COX-2 was also evaluated in an in vitro enzymatic assay. We further studied the effect of HIFPL on leukocytes migration in mice induced by thioglycollate. The level of chemokines facilitating the migration of leukocytes was also measured. We found that HIFPL (40, 80, 160 mg/kg) demonstrated anti-inflammatory activities in mice. The HIFPL reduced the volume of paw edema and COX-2 expression. However, HIFPL acts as an unselective COX-2 inhibitor as it inhibited COX-1 with a slightly higher potency. Interestingly, HIFPL strongly inhibited leukocyte migration by reducing the level of chemokines, Interleukine-8 (IL-8) and Monocyte chemoattractant protein-1 (MCP-1).

Flavocoxid, a dual inhibitor of cyclooxygenase and 5-lipoxygenase, blunts pro-inflammatory phenotype activation in endotoxin-stimulated macrophages.

PubMed

Altavilla, D; Squadrito, F; Bitto, A; Polito, F; Burnett, B P; Di Stefano, V; Minutoli, L

2009-08-01

The flavonoids, baicalin and catechin, from Scutellaria baicalensis and Acacia catechu, respectively, have been used for various clinical applications. Flavocoxid is a mixed extract containing baicalin and catechin, and acts as a dual inhibitor of cyclooxygenase (COX) and 5-lipoxygenase (LOX) enzymes. The anti-inflammatory activity, measured by protein and gene expression of inflammatory markers, of flavocoxid in rat peritoneal macrophages stimulated with Salmonella enteritidis lipopolysaccharide (LPS) was investigated. LPS-stimulated (1 microg.mL(-1)) peritoneal rat macrophages were co-incubated with different concentrations of flavocoxid (32-128 microg.mL(-1)) or RPMI medium for different incubation times. Inducible COX-2, 5-LOX, inducible nitric oxide synthase (iNOS) and inhibitory protein kappaB-alpha (IkappaB-alpha) levels were evaluated by Western blot analysis. Nuclear factor kappaB (NF-kappaB) binding activity was investigated by electrophoretic mobility shift assay. Tumour necrosis factor-alpha (TNF-alpha) gene and protein expression were measured by real-time polymerase chain reaction and enzyme-linked immunosorbent assay respectively. Finally, malondialdehyde (MDA) and nitrite levels in macrophage supernatants were evaluated. LPS stimulation induced a pro-inflammatory phenotype in rat peritoneal macrophages. Flavocoxid (128 microg.mL(-1)) significantly inhibited COX-2 (LPS = 18 +/- 2.1; flavocoxid = 3.8 +/- 0.9 integrated intensity), 5-LOX (LPS = 20 +/- 3.8; flavocoxid = 3.1 +/- 0.8 integrated intensity) and iNOS expression (LPS = 15 +/- 1.1; flavocoxid = 4.1 +/- 0.4 integrated intensity), but did not modify COX-1 expression. PGE(2) and LTB(4) levels in culture supernatants were consequently decreased. Flavocoxid also prevented the loss of IkappaB-alpha protein (LPS = 1.9 +/- 0.2; flavocoxid = 7.2 +/- 1.6 integrated intensity), blunted increased NF-kappaB binding activity (LPS = 9.2 +/- 2; flavocoxid = 2.4 +/- 0.7 integrated intensity) and the enhanced TNF-alpha mRNA levels (LPS = 8 +/- 0.9; flavocoxid = 1.9 +/- 0.8 n-fold/beta-actin) induced by LPS. Finally, flavocoxid decreased MDA, TNF and nitrite levels from LPS-stimulated macrophages. Flavocoxid might be useful as a potential anti-inflammatory agent, acting at the level of gene and protein expression.

Comparative analysis of COX-2, vascular endothelial growth factor and microvessel density in human renal cell carcinomas.

PubMed

Hemmerlein, B; Galuschka, L; Putzer, N; Zischkau, S; Heuser, M

2004-12-01

Cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF) are frequently up-regulated in malignant tumours and play a role in proliferation, apoptosis, angiogenesis and tumour invasion. In the present study, the expression of COX-2 and VEGF in renal cell carcinoma (RCC) was analysed and correlated with the microvessel density (MVD). COX-2 and VEGF were analysed by realtime reverse transcriptase-polymerase chain reaction and immunohistochemistry. The MVD was assessed by CD31 immunohistochemistry. The expression of COX-2 and VEGF was determined in the RCC cell lines A498 and Caki-1 under short-term hypoxia and in multicellular tumour cell aggregates. COX-2 was expressed in RCC by tumour epithelia, endothelia and macrophages in areas of cystic tumour regression and tumour necrosis. COX-2 protein in RCC was not altered in comparison with normal renal tissue. VEGF mRNA was up-regulated in RCC and positively correlated with MVD. RCC with high up-regulation of VEGF mRNA showed weak intracytoplasmic expression of VEGF in tumour cells. Intracytoplasmic VEGF protein expression was negatively correlated with MVD. In RCC with necrosis the MVD was reduced in comparison with RCC without necrosis. A498 RCC cells down-regulated COX-2 and up-regulated VEGF under conditions of hypoxia. In Caki-1 cells COX-2 expression remained stable, whereas VEGF was significantly up-regulated. In multicellular A498 cell aggregates COX-2 and VEGF were up-regulated centrally, whereas no gradient was found in Caki-1 cells. COX-2 and VEGF are potential therapeutic targets because COX-2 and VEGF are expressed in RCC and associated cell populations such as endothelia and monocytes/macrophages.

The transcription factor c-Fos coordinates with histone lysine-specific demethylase 2A to activate the expression of cyclooxygenase-2

PubMed Central

Du, Yipeng; Cao, Lin-lin; Li, Meiting; Shen, Changchun; Hou, Tianyun; Zhao, Ying; Wang, Haiying; Deng, Dajun; Wang, Lina; He, Qihua; Zhu, Wei-Guo

2015-01-01

Cyclooxygenase-2 (COX-2) is overexpressed in a variety of human epithelial cancers, including lung cancer, and is highly associated with a poor prognosis and a low survival rate. Understanding how COX-2 is regulated in response to carcinogens will offer insight into designing anti-cancer strategies and preventing cancer development. Here, we analyzed COX-2 expression in several human lung cancer cell lines and found that COX-2 expression was absent in the H719 and H460 cell lines by a DNA methylation-independent mechanism. The re-expression of COX-2 was observed after 12-O-tetradecanoylphorbol-13-acetate (TPA) treatment in both cell lines. Further investigation found that H3K36 dimethylation was significantly reduced near the COX-2 promoter because histone demethylase 2A (KDM2A) was recruited to the COX-2 promoter after TPA treatment. In addition, the transcription factor c-Fos was found to be required to recruit KDM2A to the COX-2 promoter for reactivation of COX-2 in response to TPA treatment in both the H719 and H460 cell lines. Together, our data reveal a novel mechanism by which the carcinogen TPA activates COX-2 expression by regulating H3K36 dimethylation near the COX-2 promoter. PMID:26430963

Wine polyphenols exert antineoplasic effect on androgen resistant PC-3 cell line through the inhibition of the transcriptional activity of COX-2 promoter mediated by NF-kβ.

PubMed

Ferruelo, A; de Las Heras, M M; Redondo, C; Ramón de Fata, F; Romero, I; Angulo, J C

2014-09-01

Mediterranean diet may play a role in the prevention of prostate cancer (PCa) development and progression. Cyclooxygenase-2 (COX-2) expression is associated with increased cellular proliferation, prevents apoptosis and favors tumor invasion. We intend to clarify whether resveratrol and other polyphenols effectively inhibit COX-2 activity and induce apoptosis in hormone-resistant PC-3 cell line. PC-3 cells were cultured and treated with different concentrations of gallic acid, tannic acid, quercetin, and resveratrol in presence of phorbol myristate acetate (PMA; 50 μg/ml) that induces COX-2 expression. Total RNA was extracted and COX-2 expression was analyzed by relative quantification real-time PCR (ΔΔCt method). COX-2 activity was determined by PGE-2 detection using ELISA. Caspase 3/7 luminescence assay was used to disclose apoptosis. Transitory transfection with short human COX-2 (phPES2 -327/+59) and p5xNF-kβ-Luc plasmids determined COX-2 promoter activity and specifically that dependant of NF-kβ. COX-2 expression was not modified in media devoid of PMA. However, under PMA induction tannic acid (2.08 ±.21), gallic acid (2.46 ±.16), quercetin (1.78 ±.14) and resveratrol (1.15 ±.16) significantly inhibited COX-2 mRNA with respect to control (3.14 ±.07), what means a 34%, 23%, 46% and 61% reduction, respectively. The inhibition in the levels of PGE-2 followed a similar pattern. All compounds studied induced apoptosis at 48 h, although at a different rate. PMA caused a rise in activity 7.4 ±.23 times phPES2 -327/+59 and 2.0 ±.1 times p5xNF-kβ-Luc at 6h compared to basal. Resveratrol suppressed these effects 17.1 ±.21 and 32.4 ±.18 times, respectively. Similarly, but to a lesser extent, the rest of evaluated polyphenols diminished PMA inductor effect on the activity of both promoters. Polyphenols inhibit transcriptional activity of COX-2 promoter mediated by NF-kβ. This effect could explain, at least in part, the induction of apoptosis in vitro by these substances in castration resistant PCa. Copyright © 2014 AEU. Published by Elsevier Espana. All rights reserved.

Modulation of Inflammatory and Profibrotic Signaling in a Rabbit Model of Acute Phonotrauma Using Triamcinolone

PubMed Central

Hall, Joseph E.; Suehiro, Atsushi; Branski, Ryan C.; Garrett, C. Gaelyn; Rousseau, Bernard

2015-01-01

Objective To investigate the hypothesis that prophylactic triamcinolone modulates acute vocal fold inflammatory and profibrotic signaling during acute phonotrauma. Study Design In vivo rabbit phonation model. Setting Academic medical center. Subjects and Methods Forty New Zealand white breeder rabbits were randomly assigned to 1 of 4 groups: control (no intervention), no treatment (30 minutes of raised intensity phonation), sham treatment (bilateral intralaryngeal triamcinolone acetonide injection at 0 μg/25 μL followed by 30 minutes of raised intensity phonation), or steroid treatment (bilateral intralaryngeal triamcinolone acetonide injection at 400 μg/25 μL followed by 30 minutes of raised intensity phonation). Quantitative polymerase chain reaction (qPCR) was used to investigate gene expression levels of cyclooxygenase-2 (COX-2), interleukin (IL)–1β, and transforming growth factor (TGF)–β1. Results Results revealed a significant main effect for COX-2 (P = .002). Post hoc testing revealed that rabbits receiving no treatment (15.10) had higher COX-2 gene expression than control (5.90; P <.001). There were no significant differences in COX-2 expression between treatment groups. Results revealed a significant main effect for IL-1β (P < .001). Post hoc testing revealed that rabbits receiving no treatment (14.70) had higher IL-1β gene expression than control (6.30) (P = .001). There were no significant differences in IL-1β gene expression between treatment groups. There were no significant differences in TGF-β1 gene expression (P = .525) between treatment and control groups. Conclusion Given conflicting evidence, further studies are necessary to investigate vocal fold steroid injections prior to and following the induction of phonotrauma. Prophylactic administration of triamcinolone immediately prior to acute phonotrauma resulted in no significant changes in COX-2, IL-1β, and TGF-β1 gene transcript levels. PMID:22399283

Manganese induces IGF-1 and cyclooxygenase-2 gene expressions in the basal hypothalamus during prepubertal female development.

PubMed

Hiney, Jill K; Srivastava, Vinod K; Dees, William Les

2011-06-01

Precocious puberty is a significant child health problem, especially in girls, because 95% of cases are idiopathic. Our earlier studies demonstrated that low-dose levels of manganese (Mn) caused precocious puberty via stimulating the secretion of luteinizing hormone-releasing hormone (LHRH). Because glial-neuronal communications are important for the activation of LHRH secretion at puberty, we investigated the effects of prepubertal Mn exposure on specific glial-derived puberty-related genes known to affect neuronal LHRH release. Animals were supplemented with MnCl(2) (10 mg/kg) or saline by gastric gavage from day 12 until day 22 or day 29, then decapitated, and brains removed. The site of LHRH release is the medial basal hypothalamus (MBH), and tissues from this area were analyzed by real-time PCR for transforming growth factor α (TGFα), insulin-like growth factor-1 (IGF-1), and cyclooxygenase-2 (COX-2) messenger RNA levels. Protein levels for IGF-1 receptor (IGF-1R) were measured by Western blot analysis. LHRH gene expression was measured in the preoptic area/anteroventral periventricular (POA/AVPV) region. In the MBH, at 22 days, IGF-1 gene expression was increased (p < 0.05) with a concomitant increase (p < 0.05) in IGF-1R protein expression. Mn also increased (p < 0.01) COX-2 gene expression. At 29 days, the upregulation of IGF-1 (p < 0.05) and COX-2 (p < 0.05) continued in the MBH. At this time, we observed increased (p < 0.05) LHRH gene expression in the POA/AVPV. Additionally, Mn stimulated prostaglandin E(2) and LHRH release from 29-day-old median eminences incubated in vitro. These results demonstrate that Mn, through the upregulation of IGF-1 and COX-2, may promote maturational events and glial-neuronal communications facilitating the increased neurosecretory activity, including that of LHRH, resulting in precocious pubertal development.

Novel Allelic Variants in the Canine Cyclooxgenase-2 (Cox-2) Promoter Are Associated with Renal Dysplasia in Dogs

PubMed Central

Whiteley, Mary H.; Bell, Jerold S.; Rothman, Debby A.

2011-01-01

Renal dysplasia (RD) in dogs is a complex disease with a highly variable phenotype and mode of inheritance that does not follow a simple Mendelian pattern. Cox-2 (Cyclooxgenase-2) deficient mice have renal abnormalities and a pathology that has striking similarities to RD in dogs suggesting to us that mutations in the Cox-2 gene could be the cause of RD in dogs. Our data supports this hypothesis. Sequencing of the canine Cox-2 gene was done from clinically affected and normal dogs. Although no changes were detected in the Cox-2 coding region, small insertions and deletions of GC boxes just upstream of the ATG translation start site were found. These sequences are putative SP1 transcription factor binding sites that may represent important cis-acting DNA regulatory elements that govern the expression of Cox-2. A pedigree study of a family of Lhasa apsos revealed an important statistical correlation of these mutant alleles with the disease. We examined an additional 22 clinical cases from various breeds. Regardless of the breed or severity of disease, all of these had one or two copies of the Cox-2 allelic variants. We suggest that the unusual inheritance pattern of RD is due to these alleles, either by changing the pattern of expression of Cox-2 or making Cox-2 levels susceptible to influences of other genes or environmental factors that play an unknown but important role in the development of RD in dogs. PMID:21346820

Flavocoxid Inhibits Phospholipase A2, Peroxidase Moieties of the Cyclooxygenases (COX), and 5-Lipoxygenase, Modifies COX-2 Gene Expression, and Acts as an Antioxidant

PubMed Central

Burnett, Bruce P.; Bitto, Alessandra; Altavilla, Domenica; Squadrito, Francesco; Levy, Robert M.; Pillai, Lakshmi

2011-01-01

The multiple mechanisms of action for flavocoxid relating to arachidonic acid (AA) formation and metabolism were studied in vitro. Flavocoxid titrated into rat peritoneal macrophage cultures inhibited cellular phospholipase A2 (PLA2) (IC50 = 60 μg/mL). In in vitro enzyme assays, flavocoxid showed little anti-cyclooxygenase (CO) activity on COX-1/-2 enzymes, but inhibited the COX-1 (IC50 = 12.3) and COX-2 (IC50 = 11.3 μg/mL) peroxidase (PO) moieties as well as 5-lipoxygenase (5-LOX) (IC50 = 110 μg/mL). No detectable 5-LOX inhibition was found for multiple traditional and COX-2 selective NSAIDs. Flavocoxid also exhibited strong and varied antioxidant capacities in vitro and decreased nitrite levels (IC50 = 38 μg/mL) in rat peritoneal macrophages. Finally, in contrast to celecoxib and ibuprofen, which upregulated the cox-2 gene, flavocoxid strongly decreased expression. This work suggests that clinically favourable effects of flavocoxid for management of osteoarthritis (OA) are achieved by simultaneous modification of multiple molecular pathways relating to AA metabolism, oxidative induction of inflammation, and neutralization of reactive oxygen species (ROS). PMID:21765617

Flavocoxid inhibits phospholipase A2, peroxidase moieties of the cyclooxygenases (COX), and 5-lipoxygenase, modifies COX-2 gene expression, and acts as an antioxidant.

PubMed

Burnett, Bruce P; Bitto, Alessandra; Altavilla, Domenica; Squadrito, Francesco; Levy, Robert M; Pillai, Lakshmi

2011-01-01

The multiple mechanisms of action for flavocoxid relating to arachidonic acid (AA) formation and metabolism were studied in vitro. Flavocoxid titrated into rat peritoneal macrophage cultures inhibited cellular phospholipase A2 (PLA(2)) (IC(50) = 60 μg/mL). In in vitro enzyme assays, flavocoxid showed little anti-cyclooxygenase (CO) activity on COX-1/-2 enzymes, but inhibited the COX-1 (IC(50) = 12.3) and COX-2 (IC(50) = 11.3 μg/mL) peroxidase (PO) moieties as well as 5-lipoxygenase (5-LOX) (IC(50) = 110 μg/mL). No detectable 5-LOX inhibition was found for multiple traditional and COX-2 selective NSAIDs. Flavocoxid also exhibited strong and varied antioxidant capacities in vitro and decreased nitrite levels (IC(50) = 38 μg/mL) in rat peritoneal macrophages. Finally, in contrast to celecoxib and ibuprofen, which upregulated the cox-2 gene, flavocoxid strongly decreased expression. This work suggests that clinically favourable effects of flavocoxid for management of osteoarthritis (OA) are achieved by simultaneous modification of multiple molecular pathways relating to AA metabolism, oxidative induction of inflammation, and neutralization of reactive oxygen species (ROS).

DNA-hypomethylating agent, 5'-azacytidine, induces cyclooxygenase-2 expression via the PI3-kinase/Akt and extracellular signal-regulated kinase-1/2 pathways in human HT1080 fibrosarcoma cells.

PubMed

Yu, Seon-Mi; Kim, Song-Ja

2015-10-01

The cytosine analogue 5'-azacytidine (5'-aza) induces DNA hypomethylation by inhibiting DNA methyltransferase. In clinical trials, 5'-aza is widely used in epigenetic anticancer treatments. Accumulated evidence shows that cyclooxygenase-2 (COX-2) is overexpressed in various cancers, indicating that it may play a critical role in carcinogenesis. However, few studies have been performed to explore the molecular mechanism underlying the increased COX-2 expression. Therefore, we tested the hypothesis that 5'-aza regulates COX-2 expression and prostaglandin E2 (PGE2) production. The human fibrosarcoma cell line HT1080, was treated with various concentrations of 5'-aza for different time periods. Protein expressions of COX-2, DNA (cytosine-5)-methyltransferase 1 (DNMT1), pAkt, Akt, extracellular signal-regulated kinase (ERK), and phosphorylated ERK (pERK) were determined using western blot analysis, and COX-2 mRNA expression was determined using RT-PCR. PGE2 production was evaluated using the PGE2 assay kit. The localization and expression of COX-2 were determined using immunofluorescence staining. Treatment with 5'-aza induces protein and mRNA expression of COX-2. We also observed that 5'-aza-induced COX-2 expression and PGE2 production were inhibited by S-adenosylmethionine (SAM), a methyl donor. Treatment with 5'-aza phosphorylates PI3-kinase/Akt and ERK-1/2; inhibition of these pathways by LY294002, an inhibitor of PI3-kinase/Akt, or PD98059, an inhibitor of ERK-1/2, respectively, prevents 5'-aza-induced COX-2 expression and PGE2 production. Overall, these observations indicate that the hypomethylating agent 5'-aza modulates COX-2 expression via the PI3-kinase/Akt and ERK-1/2 pathways in human HT1080 fibrosarcoma cells.

Significance of Cox-2 expression in rectal cancers with or without preoperative radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pachkoria, Ketevan; Zhang Hong; Adell, Gunnar

2005-11-01

Purpose: Radiotherapy has reduced local recurrence of rectal cancers, but the result is not satisfactory. Further biologic factors are needed to identify patients for more effective radiotherapy. Our aims were to investigate the relationship of cyclooxygenase-2 (Cox-2) expression to radiotherapy, and clinicopathologic/biologic variables in rectal cancers with or without radiotherapy. Methods and Materials: Cox-2 expression was immunohistochemically examined in distal normal mucosa (n = 28), in adjacent normal mucosa (n = 107), in primary cancer (n = 138), lymph node metastasis (n = 30), and biopsy (n = 85). The patients participated in a rectal cancer trial of preoperative radiotherapy.more » Results: Cox-2 expression was increased in primary tumor compared with normal mucosa (p < 0.0001), but there was no significant change between primary tumor and metastasis. Cox-2 positivity was or tended to be related to more p53 and Ki-67 expression, and less apoptosis (p {<=} 0.05). In Cox-2-negative cases of either biopsy (p = 0.01) or surgical samples (p = 0.02), radiotherapy was related to less frequency of local recurrence, but this was not the case in Cox-2-positive cases. Conclusion: Cox-2 expression seemed to be an early event involved in rectal cancer development. Radiotherapy might reduce a rate of local recurrence in the patients with Cox-2 weakly stained tumors, but not in those with Cox-2 strongly stained tumors.« less

Hepatocyte growth factor upregulation promotes carcinogenesis and epithelial-mesenchymal transition in hepatocellular carcinoma via Akt and COX-2 pathways

PubMed Central

Ogunwobi, Olorunseun O.

2013-01-01

Advanced hepatocellular carcinoma (HCC) is an important cause of cancer mortality. Epithelial-mesenchymal transition (EMT) has been shown to be an important biological process in cancer progression and metastasis. We have focused on elucidating factors that induce EMT to promote carcinogenesis and subsequent metastasis in HCC using the BNL CL.2 (BNL) and BNL 1ME A. 7R.1 (1MEA) cell lines. BNL cells are normal hepatocytes whereas the 1MEA cells are HCC cells derived from chemical transformation of the BNL cells. Their morphological characteristics were examined. Expression levels of hepatocyte growth factor (HGF), markers of EMT and mediators of HGF signaling were determined and functional characteristics were compared. BNL cells were treated with HGF and effects on EMT-marker and mediators of HGF signaling were analyzed. BNL cells display characteristic epithelial morphology whereas 1MEA cells display mesenchymal characteristics. 1MEA cells express and secrete more HGF than BNL cells. There was significantly decreased expression of E-cadherin, albumin, AAT and increased expression of fibronectin, collagen-1, vimentin, snail and slug in 1MEA cells. There was also increased expression of cyclooxygenase-2 (COX-2), Akt and phosphorylated Akt (pAkt) in 1MEA cells. Moreover, 1MEA cells had increased migratory capacity inhibited by inhibition of COX-2 and Akt but not extracellular signal regulated kinase (ERK). Molecular mesenchymal characteristics of 1MEA cells were reversed by inhibition of COX-2, Akt and ERK. Treatment of BNL cells with HGF led to decreased expression of E-cadherin and increased expression of fibronectin, vimentin, snail, slug, COX-2, Akt, pAkt and increased migration, invasiveness and clonogenicity. We conclude that development of HCC is associated with upregulation of HGF which promotes EMT and carcinogenesis via upregulation of COX-2 and Akt. Consequently, HGF signaling may be targeted for therapy in advanced and metastatic HCC. PMID:21744257

Hepatocyte growth factor upregulation promotes carcinogenesis and epithelial-mesenchymal transition in hepatocellular carcinoma via Akt and COX-2 pathways.

PubMed

Ogunwobi, Olorunseun O; Liu, Chen

2011-12-01

Advanced hepatocellular carcinoma (HCC) is an important cause of cancer mortality. Epithelial-mesenchymal transition (EMT) has been shown to be an important biological process in cancer progression and metastasis. We have focused on elucidating factors that induce EMT to promote carcinogenesis and subsequent metastasis in HCC using the BNL CL.2 (BNL) and BNL 1ME A. 7R.1 (1MEA) cell lines. BNL cells are normal hepatocytes whereas the 1MEA cells are HCC cells derived from chemical transformation of the BNL cells. Their morphological characteristics were examined. Expression levels of hepatocyte growth factor (HGF), markers of EMT and mediators of HGF signaling were determined and functional characteristics were compared. BNL cells were treated with HGF and effects on EMT-marker and mediators of HGF signaling were analyzed. BNL cells display characteristic epithelial morphology whereas 1MEA cells display mesenchymal characteristics. 1MEA cells express and secrete more HGF than BNL cells. There was significantly decreased expression of E-cadherin, albumin, AAT and increased expression of fibronectin, collagen-1, vimentin, snail and slug in 1MEA cells. There was also increased expression of cyclooxygenase-2 (COX-2), Akt and phosphorylated Akt (pAkt) in 1MEA cells. Moreover, 1MEA cells had increased migratory capacity inhibited by inhibition of COX-2 and Akt but not extracellular signal regulated kinase (ERK). Molecular mesenchymal characteristics of 1MEA cells were reversed by inhibition of COX-2, Akt and ERK. Treatment of BNL cells with HGF led to decreased expression of E-cadherin and increased expression of fibronectin, vimentin, snail, slug, COX-2, Akt, pAkt and increased migration, invasiveness and clonogenicity. We conclude that development of HCC is associated with upregulation of HGF which promotes EMT and carcinogenesis via upregulation of COX-2 and Akt. Consequently, HGF signaling may be targeted for therapy in advanced and metastatic HCC.

BDNF and COX-2 participate in anti-depressive mechanisms of catalpol in rats undergoing chronic unpredictable mild stress.

PubMed

Wang, Jun-Ming; Yang, Lian-He; Zhang, Yue-Yue; Niu, Chun-Ling; Cui, Ying; Feng, Wei-Sheng; Wang, Gui-Fang

2015-11-01

Catalpol, a major compound in Rehmannia glutinosa with both medicinal and nutritional values, has been previously confirmed to shorten the duration of immobility in mice exposed to tail suspension and forced swimming tests. This study attempted to examine the anti-depressive mechanisms of catalpol in rats undergoing chronic unpredictable mild stress (CUMS) by involving brain-derived neurotrophic factor (BDNF) and cyclooxygenase-2 (COX-2). CUMS-exposed rats were given catalpol daily (5, 10, and 20mg/kg, ig) or a reference drug, fluoxetine hydrochloride (FH, 10mg/kg, ig), at 5 weeks after starting the CUMS procedure. Sucrose preference test was performed to observe depression-like behavior, and serum and brain tissues were used for neurochemical and fluorescent quantitative reverse transcription PCR analysis. CUMS induced depression-like behavior, whereas catalpol and FH administration attenuated this symptom. Moreover, CUMS caused excessively elevated levels of serum corticosterone, an index of hypothalamic-pituitary-adrenal (HPA) axis hyperactivation, in a manner attenuated by catalpol and FH administration. Catalpol administration also further decreased BDNF activities, downregulated the mRNA expression of BDNF and tropomyosin-related kinase B (TrkB), and reversed the excessive elevation in the activities and mRNA expression levels of COX-2 and prostaglandin E2 (PGE2) in the hippocampus and frontal cortex of rats undergoing CUMS. Results indicate that catalpol can ameliorate CUMS-induced depression-like behavior, and suggest its mechanisms may partially be ascribed to restoring HPA axis dysfunctions, upregulating BDNF expression and its cognate receptor TrkB, and downregulating COX-2 expression, thereby reducing PGE2 levels in the brain. Copyright © 2015 Elsevier Inc. All rights reserved.

Mechanisms underlying the growth inhibitory effects of the cyclo-oxygenase-2 inhibitor celecoxib in human breast cancer cells.

PubMed

Basu, Gargi D; Pathangey, Latha B; Tinder, Teresa L; Gendler, Sandra J; Mukherjee, Pinku

2005-01-01

Inhibitors of cyclo-oxygenase (COX)-2 are being extensively studied as anticancer agents. In the present study we evaluated the mechanisms by which a highly selective COX-2 inhibitor, celecoxib, affects tumor growth of two differentially invasive human breast cancer cell lines. MDA-MB-231 (highly invasive) and MDA-MB-468 (moderately invasive) cell lines were treated with varying concentrations of celecoxib in vitro, and the effects of this agent on cell growth and angiogenesis were monitored by evaluating cell proliferation, apoptosis, cell cycle arrest, and vasculogenic mimicry. The in vitro results of MDA-MB-231 cell line were further confirmed in vivo in a mouse xenograft model. The highly invasive MDA-MB-231 cells express higher levels of COX-2 than do the less invasive MDA-MB-468 cells. Celecoxib treatment inhibited COX-2 activity, indicated by prostaglandin E2 secretion, and caused significant growth arrest in both breast cancer cell lines. In the highly invasive MDA-MB-231 cells, the mechanism of celecoxib-induced growth arrest was by induction of apoptosis, associated with reduced activation of protein kinase B/Akt, and subsequent activation of caspases 3 and 7. In the less invasive MDA-MB-468 cells, growth arrest was a consequence of cell cycle arrest at the G0/G1 checkpoint. Celecoxib-induced growth inhibition was reversed by addition of exogenous prostaglandin E2 in MDA-MB-468 cells but not in MDA-MB-231 cells. Furthermore, MDA-MB-468 cells formed significantly fewer extracellular matrix associated microvascular channels in vitro than did the high COX-2 expressing MDA-MB-231 cells. Celecoxib treatment not only inhibited cell growth and vascular channel formation but also reduced vascular endothelial growth factor levels. The in vitro findings corroborated in vivo data from a mouse xenograft model in which daily administration of celecoxib significantly reduced tumor growth of MDA-MB-231 cells, which was associated with reduced vascularization and increased necrosis in the tumor mass. The disparate molecular mechanisms of celecoxib-induced growth inhibition in human breast cancer cells depends upon the level of COX-2 expression and the invasive potential of the cell lines examined. Data suggest a role for COX-2 not only in the growth of cancer cells but also in activating the angiogenic pathway through regulating levels of vascular endothelial growth factor.

Curcumin inhibits interferon-{alpha} induced NF-{kappa}B and COX-2 in human A549 non-small cell lung cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Jeeyun; Im, Young-Hyuck; Jung, Hae Hyun

2005-08-26

The A549 cells, non-small cell lung cancer cell line from human, were resistant to interferon (IFN)-{alpha} treatment. The IFN-{alpha}-treated A549 cells showed increase in protein expression levels of NF-{kappa}B and COX-2. IFN-{alpha} induced NF-{kappa}B binding activity within 30 min and this increased binding activity was markedly suppressed with inclusion of curcumin. Curcumin also inhibited IFN-{alpha}-induced COX-2 expression in A549 cells. Within 10 min, IFN-{alpha} rapidly induced the binding activity of a {gamma}-{sup 32}P-labeled consensus GAS oligonucleotide probe, which was profoundly reversed by curcumin. Taken together, IFN-{alpha}-induced activations of NF-{kappa}B and COX-2 were inhibited by the addition of curcumin in A549more » cells.« less

Dimethylthiourea ameliorates carbon tetrachloride-induced acute liver injury in ovariectomized mice.

PubMed

Mitazaki, Satoru; Kotajima, Natsumi; Matsuda, Sakiko; Ida, Naruki; Iide, Mina; Honma, Shigeyoshi; Suto, Miwako; Kato, Naho; Kuroda, Naohito; Hiraiwa, Kouichi; Yoshida, Makoto; Abe, Sumiko

2018-08-01

In order to clarify hepato-protective actions of estrogen, we examined the progress of carbon tetrachloride (CCl 4 )-induced acute liver injury (ALI) in sham and ovariectomized (ovx) mice and the effects of dimethylthiourea (DMTU), a hydroxyl radical scavenger, and meloxicam (Melo), a selective cox-2 inhibitor, on the development of CCl 4 -induced ALI. Female C57BL/6 J mice weighing 15-20 g were performed sham or ovx operation at 8 weeks of age. Blood and liver samples were collected 15 and 24 h after CCl 4 administration. Sham and ovx mice were given DMTU, Melo or saline intraperitoneally 30 min before CCl 4 or corn oil administration. ALT levels in ovx mice were significantly increased compared to those in sham mice. DMTU reduced ALT levels in ovx mice to the same levels as those in sham mice after CCl 4 injection. CCl 4 upregulated TNF-α, IL-6, cox-2 and iNOS expression in ovx mice compared to the levels in sham mice. DMTU significantly reduced cox-2 and iNOS expression levels upregulated by CCl 4 in ovx mice. However, pretreatment with Melo had no effects on ALT levels and the gene expression levels of TNF-α, IL-6 and HO-1 in either sham or ovx mice, indicating that cox-2 may not participate in increase of CCl 4 -induced ALI caused by estrogen deficiency. Ovariectomy accelerated the development of CCl 4 -induced acute liver injury, and DMTU reduced liver injury. These results suggest that estrogen may act as an antioxidant in the development CCl 4 -induced acute liver injury. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Altered monocyte cyclo-oxygenase response in non-obese diabetic mice.

PubMed

Beyan, H; Buckley, L R; Bustin, S A; Yousaf, N; Pozzilli, P; Leslie, R D

2009-02-01

Monocytes infiltrate islets in non-obese diabetic (NOD) mice. Activated monocyte/macrophages express cyclo-oxygenase-2 (COX-2) promoting prostaglandin-E(2) (PGE(2)) secretion, while COX-1 expression is constitutive. We investigated in female NOD mice: (i) natural history of monocyte COX expression basally and following lipopolysaccharide (LPS) stimulation; (ii) impact of COX-2 specific inhibitor (Vioxx) on PGE(2), insulitis and diabetes. CD11b(+) monocytes were analysed for COX mRNA expression from NOD (n = 48) and C57BL/6 control (n = 18) mice. NOD mice were treated with either Vioxx (total dose 80 mg/kg) (n = 29) or methylcellulose as control (n = 29) administered by gavage at 4 weeks until diabetes developed or age 30 weeks. In all groups, basal monocyte COX mRNA and PGE(2) secretion were normal, while following LPS, after 5 weeks of age monocyte/macrophage COX-1 mRNA decreased (P < 0.01) and COX-2 mRNA increased (P < 0.01). However, diabetic NOD mice had reduced COX mRNA response (P = 0.03). Vioxx administration influenced neither PGE(2), insulitis nor diabetes. We demonstrate an isoform switch in monocyte/macrophage COX mRNA expression following LPS, which is altered in diabetic NOD mice as in human diabetes. However, Vioxx failed to affect insulitis or diabetes. We conclude that monocyte responses are altered in diabetic NOD mice but COX-2 expression is unlikely to be critical to disease risk.

Anti-nociceptive effect of patchouli alcohol: Involving attenuation of cyclooxygenase 2 and modulation of mu-opioid receptor.

PubMed

Yu, Xuan; Wang, Xin-Pei; Yan, Xiao-Jin; Jiang, Jing-Fei; Lei, Fan; Xing, Dong-Ming; Guo, Yue-Ying; Du, Li-Jun

2017-08-09

To explore the anti-nociceptive effect of patchouli alcohol (PA), the essential oil isolated from Pogostemon cablin (Blanco) Bent, and determine the mechanism in molecular levels. The acetic acid-induced writhing test and formalin-induced plantar injection test in mice were employed to confifirm the effect in vivo. Intracellular calcium ion was imaged to verify PA on mu-opioid receptor (MOR). Cyclooxygenase 2 (COX2) and MOR of mouse brain were expressed for determination of PA's target. Cellular experiments were carried out to find out COX2 and MOR expression induced by PA. PA significantly reduced latency period of visceral pain and writhing induced by acetic acid saline solution (P<0.01) and allodynia after intra-plantar formalin (P<0.01) in mice. PA also up-regulated COX2 mRNA and protein (P<0.05) with a down-regulation of MOR (P<0.05) both in in vivo and in vitro experiments, which devote to the analgesic effect of PA. A decrease in the intracellular calcium level (P<0.05) induced by PA may play an important role in its anti-nociceptive effect. PA showed the characters of enhancing the MOR expression and reducing the intracellular calcium ion similar to opioid effect. Both COX2 and MOR are involved in the mechanism of PA's anti-nociceptive effect, and the up-regulation of the receptor expression and the inhibition of intracellular calcium are a new perspective to PA's effect on MOR.

Immunohistochemical analysis of cyclooxygenase-2 and brain fatty acid binding protein expression in grades I-II meningiomas: correlation with tumor grade and clinical outcome after radiotherapy.

PubMed

Kang, Hyun-Cheol; Kim, Il Han; Park, Charn Il; Park, Sung-Hye

2014-10-01

This study was done to evaluate the association of cyclooxygenase 2 (COX-2) and brain fatty acid binding protein (BFABP) with tumor grade and outcome of grades I-II meningiomas treated with radiotherapy. From 1996 to 2008, 40 patients with intracranial grades I-II meningiomas were treated with radiotherapy. Immunohistochemical staining for COX-2 and BFABP were performed on formalin-fixed paraffin-embedded tissues. COX-2 expression was significantly associated with BFABP status and both COX-2 (P < 0.01) and BFABP (P = 0.01) expression were stronger in the grade II meningiomas than in grade I tumors. Among the clinicopathologic factors, age and COX-2 status were prognostic in progression-free survival. Patients with moderate or strong COX-2 expression had worse outcome than those with negative or weak COX-2 expression (P = 0.03) after controlling for potential confounders. Our results suggest that the molecular biomarker COX-2 has prognostic significance in intracranial grades I-II meningiomas following radiotherapy. © 2014 Japanese Society of Neuropathology.

CD40 engagement on dendritic cells induces cyclooxygenase-2 and EP2 receptor via p38 and ERK MAPKs.

PubMed

Harizi, Hedi; Limem, Ilef; Gualde, Norbert

2011-02-01

We have previously reported that cyclooxygenase (COX)-2-derived prostaglandin (PG)E2 critically regulates dendritic cell (DC) inflammatory phenotype and function through EP2/EP4 receptor subtypes. As genes activated by CD40 engagement are directly relevant to inflammation, we examined the effects of CD40 activation on inflammatory PGs in murine bone marrow-derived DC (mBM-DC). We showed for the first time that activation of mBM-DC with agonist anti-CD40 monoclonal antibody (anti-CD40 mAb) dose dependently induces the synthesis of significant amounts of PGE2 via inducible expression of COX-2 enzyme, as NS-398, a COX-2-selective inhibitor reduces this upregulation. In contrast to lipopolysaccharide, which upregulates mBM-DC surface levels of EP2 and EP4 receptors, CD40 crosslinking on mBM-DC increases EP2, but not EP4, receptor expression. Flow cytometry analysis and radioligand-binding assay showed that EP2 was the major EP receptor subtype, which binds to PGE2 at the surface of anti-CD40-activated mBM-DC. Upregulation of COX-2 and EP2 levels by CD40 engagement was accompanied by dose-dependent phosphorylation of p38 and ERK1/2 mitogen-activated protein kinase (MAPK) and was abrogated by inhibitors of both pathways. Collectively, we demonstrated that CD40 engagement on mBM-DC upregulates COX-2 and EP2 receptor expression through activation of p38 and ERK1/2 MAPK signaling. Triggering the PGE2/EP2 pathway by anti-CD40 mAb resulted on the induction of Th2 immune response. Thus, CD40-induced production of PGE2 by mBM-DC could represent a negative feedback mechanism involving EP2 receptor and limiting the propagation of Th1 responses. Blocking CD40 pathway may represent a novel therapeutic pathway of inhibiting COX-2-derived prostanoids in chronically inflamed tissues (that is, arthritis).

Cyclooxygenase-2 Selectively Controls Renal Blood Flow Through a Novel PPARβ/δ-Dependent Vasodilator Pathway.

PubMed

Kirkby, Nicholas S; Sampaio, Walkyria; Etelvino, Gisele; Alves, Daniele T; Anders, Katie L; Temponi, Rafael; Shala, Fisnik; Nair, Anitha S; Ahmetaj-Shala, Blerina; Jiao, Jing; Herschman, Harvey R; Xiaomeng, Wang; Wahli, Walter; Santos, Robson A; Mitchell, Jane A

2018-02-01

Cyclooxygenase-2 (COX-2) is an inducible enzyme expressed in inflammation and cancer targeted by nonsteroidal anti-inflammatory drugs. COX-2 is also expressed constitutively in discreet locations where its inhibition drives gastrointestinal and cardiovascular/renal side effects. Constitutive COX-2 expression in the kidney regulates renal function and blood flow; however, the global relevance of the kidney versus other tissues to COX-2-dependent blood flow regulation is not known. Here, we used a microsphere deposition technique and pharmacological COX-2 inhibition to map the contribution of COX-2 to regional blood flow in mice and compared this to COX-2 expression patterns using luciferase reporter mice. Across all tissues studied, COX-2 inhibition altered blood flow predominantly in the kidney, with some effects also seen in the spleen, adipose, and testes. Of these sites, only the kidney displayed appreciable local COX-2 expression. As the main site where COX-2 regulates blood flow, we next analyzed the pathways involved in kidney vascular responses using a novel technique of video imaging small arteries in living tissue slices. We found that the protective effect of COX-2 on renal vascular function was associated with prostacyclin signaling through PPARβ/δ (peroxisome proliferator-activated receptor-β/δ). These data demonstrate the kidney as the principle site in the body where local COX-2 controls blood flow and identifies a previously unreported PPARβ/δ-mediated renal vasodilator pathway as the mechanism. These findings have direct relevance to the renal and cardiovascular side effects of drugs that inhibit COX-2, as well as the potential of the COX-2/prostacyclin/PPARβ/δ axis as a therapeutic target in renal disease. © 2018 The Authors.

Increased Dietary Sodium Induces COX2 Expression by activating NFκB in Renal Medullary Interstitial Cells

PubMed Central

Zhao, Min; Davis, Linda S.; Blackwell, Timothy S.; Yull, Fiona; Breyer, Matthew D.; Hao, Chuan-Ming

2013-01-01

High salt diet induces renal medullary COX2 expression. Selective blockade of renal medullary COX2 activity in rats causes salt sensitive hypertension, suggesting a role for renal medullary COX2 in maintaining systemic sodium balance. The present study characterized the cellular location of COX2 induction in the kidney of mice following high salt diet and examined the role of NFκB in mediating this COX2 induction in response to increased dietary salt. High salt diet (8% NaCl) for 3 days markedly increased renal medullary COX2 expression in C57Bl/6J mice. Co-immunofluorescence using a COX2 antibody and antibodies against AQP2, ClC-K, AQP1 and CD31 showed that high salt diet-induced COX2 was selectively expressed in renal medullary interstitial cells. By using NFκB reporter transgenic mice, we observed a 7 fold increase of luciferase activity in the renal medulla of the NFκB-luciferase reporter mice following high salt diet, and a robust induction of EGFP expression mainly in renal medullary interstitial cells of the NFκB-EGFP reporter mice following high salt diet. Treating high salt diet fed C57Bl/6J mice with selective IκB kinase inhibitor IMD-0354 (8mg/kg bw) substantially suppressed COX2 induction in renal medulla, and also significantly reduced urinary PGE2. These data therefore suggest that renal medullary interstitial cell NFκB plays an important role in mediating renal medullary COX2 expression and promoting renal PGE2 synthesis in response to increased dietary sodium. PMID:23900806

Fluid shear stress induces upregulation of COX-2 and PGI2 release in endothelial cells via a pathway involving PECAM-1, PI3K, FAK, and p38.

PubMed

Russell-Puleri, Sparkle; Dela Paz, Nathaniel G; Adams, Diana; Chattopadhyay, Mitali; Cancel, Limary; Ebong, Eno; Orr, A Wayne; Frangos, John A; Tarbell, John M

2017-03-01

Vascular endothelial cells play an important role in the regulation of vascular function in response to mechanical stimuli in both healthy and diseased states. Prostaglandin I 2 (PGI 2 ) is an important antiatherogenic prostanoid and vasodilator produced in endothelial cells through the action of the cyclooxygenase (COX) isoenzymes COX-1 and COX-2. However, the mechanisms involved in sustained, shear-induced production of COX-2 and PGI 2 have not been elucidated but are determined in the present study. We used cultured endothelial cells exposed to steady fluid shear stress (FSS) of 10 dyn/cm 2 for 5 h to examine shear stress-induced induction of COX-2/PGI 2 Our results demonstrate the relationship between the mechanosensor platelet endothelial cell adhesion molecule-1 (PECAM-1) and the intracellular mechanoresponsive molecules phosphatidylinositol 3-kinase (PI3K), focal adhesion kinase (FAK), and mitogen-activated protein kinase p38 in the FSS induction of COX-2 expression and PGI 2 release. Knockdown of PECAM-1 (small interference RNA) expression inhibited FSS-induced activation of α 5 β 1 -integrin, upregulation of COX-2, and release of PGI 2 in both bovine aortic endothelial cells (BAECs) and human umbilical vein endothelial cells (HUVECs). Furthermore, inhibition of the PI3K pathway (LY294002) substantially inhibited FSS activation of α 5 β 1 -integrin, upregulation of COX-2 gene and protein expression, and release of PGI 2 in BAECs. Inhibition of integrin-associated FAK (PF573228) and MAPK p38 (SB203580) also inhibited the shear-induced upregulation of COX-2. Finally, a PECAM-1 -/- mouse model was characterized by reduced COX-2 immunostaining in the aorta and reduced plasma PGI 2 levels compared with wild-type mice, as well as complete inhibition of acute flow-induced PGI 2 release compared with wild-type animals. NEW & NOTEWORTHY In this study we determined the major mechanotransduction pathway by which blood flow-driven shear stress activates cyclooxygenase-2 (COX-2) and prostaglandin I 2 (PGI 2 ) release in endothelial cells. Our work has demonstrated for the first time that COX-2/PGI 2 mechanotransduction is mediated by the mechanosensor platelet endothelial cell adhesion molecule-1 (PECAM-1). Copyright © 2017 the American Physiological Society.

Fluid shear stress induces upregulation of COX-2 and PGI2 release in endothelial cells via a pathway involving PECAM-1, PI3K, FAK, and p38

PubMed Central

Russell-Puleri, Sparkle; dela Paz, Nathaniel G.; Adams, Diana; Chattopadhyay, Mitali; Cancel, Limary; Ebong, Eno; Orr, A. Wayne; Frangos, John A.

2017-01-01

Vascular endothelial cells play an important role in the regulation of vascular function in response to mechanical stimuli in both healthy and diseased states. Prostaglandin I2 (PGI2) is an important antiatherogenic prostanoid and vasodilator produced in endothelial cells through the action of the cyclooxygenase (COX) isoenzymes COX-1 and COX-2. However, the mechanisms involved in sustained, shear-induced production of COX-2 and PGI2 have not been elucidated but are determined in the present study. We used cultured endothelial cells exposed to steady fluid shear stress (FSS) of 10 dyn/cm2 for 5 h to examine shear stress-induced induction of COX-2/PGI2. Our results demonstrate the relationship between the mechanosensor platelet endothelial cell adhesion molecule-1 (PECAM-1) and the intracellular mechanoresponsive molecules phosphatidylinositol 3-kinase (PI3K), focal adhesion kinase (FAK), and mitogen-activated protein kinase p38 in the FSS induction of COX-2 expression and PGI2 release. Knockdown of PECAM-1 (small interference RNA) expression inhibited FSS-induced activation of α5β1-integrin, upregulation of COX-2, and release of PGI2 in both bovine aortic endothelial cells (BAECs) and human umbilical vein endothelial cells (HUVECs). Furthermore, inhibition of the PI3K pathway (LY294002) substantially inhibited FSS activation of α5β1-integrin, upregulation of COX-2 gene and protein expression, and release of PGI2 in BAECs. Inhibition of integrin-associated FAK (PF573228) and MAPK p38 (SB203580) also inhibited the shear-induced upregulation of COX-2. Finally, a PECAM-1−/− mouse model was characterized by reduced COX-2 immunostaining in the aorta and reduced plasma PGI2 levels compared with wild-type mice, as well as complete inhibition of acute flow-induced PGI2 release compared with wild-type animals. NEW & NOTEWORTHY In this study we determined the major mechanotransduction pathway by which blood flow-driven shear stress activates cyclooxygenase-2 (COX-2) and prostaglandin I2 (PGI2) release in endothelial cells. Our work has demonstrated for the first time that COX-2/PGI2 mechanotransduction is mediated by the mechanosensor platelet endothelial cell adhesion molecule-1 (PECAM-1). PMID:28011582

The natural dual cyclooxygenase and 5-lipoxygenase inhibitor flavocoxid is protective in EAE through effects on Th1/Th17 differentiation and macrophage/microglia activation.

PubMed

Kong, Weimin; Hooper, Kirsten M; Ganea, Doina

2016-03-01

Prostaglandins and leukotrienes, bioactive mediators generated by cyclooxygenases (COX) and 5-lipoxygenase (5-LO) from arachidonic acid, play an essential role in neuroinflammation. High levels of LTB4 and PGE2 and increased expression of COX and 5-LO, as well as high expression of PGE2 receptors were reported in multiple sclerosis (MS) patients and in experimental autoimmune encephalomyelitis (EAE). Prostaglandins and leukotrienes have an interdependent and compensatory role in EAE, which led to the concept of therapy using dual COX/5-LO inhibitors. The plant derived flavocoxid, a dual COX/5-LO inhibitor with anti-inflammatory and antioxidant properties, manufactured as a prescription pharmaconutrient, was reported to be neuroprotective in models of transient ischemic stroke and brain injury. The present study is the first report on prophylactic and therapeutic effects of flavocoxid in EAE. The beneficial effects correlate with reduced expression of proinflammatory cytokines and of COX2 and 5-LO in spinal cords and spleens of EAE mice. The protective mechanisms include: 1. reduction in expression of MHCII/costimulatory molecules and production of proinflammatory cytokines; 2. promotion of the M2 phenotype including IL-10 expression and release by macrophages and microglia; 3. inhibition of Th1 and Th17 differentiation through direct effects on T cells. The direct inhibitory effect on Th1/Th17 differentiation, and promoting the development of M2 macrophages and microglia, represent novel mechanisms for the flavocoxid anti-inflammatory activity. As a dual COX/5-LO inhibitor with antioxidant properties, flavocoxid might be useful as a potential therapeutic medical food agent in MS patients. Copyright © 2015. Published by Elsevier Inc.

Assessment of MMP-9, TIMP-1, and COX-2 in normal tissue and in advanced symptomatic and asymptomatic carotid plaques

PubMed Central

2011-01-01

Background Mature carotid plaques are complex structures, and their histological classification is challenging. The carotid plaques of asymptomatic and symptomatic patients could exhibit identical histological components. Objectives To investigate whether matrix metalloproteinase 9 (MMP-9), tissue inhibitor of MMP (TIMP), and cyclooxygenase-2 (COX-2) have different expression levels in advanced symptomatic carotid plaques, asymptomatic carotid plaques, and normal tissue. Methods Thirty patients admitted for carotid endarterectomy were selected. Each patient was assigned preoperatively to one of two groups: group I consisted of symptomatic patients (n = 16, 12 males, mean age 66.7 ± 6.8 years), and group II consisted of asymptomatic patients (n = 14, 8 males, mean age 67.6 ± 6.81 years). Nine normal carotid arteries were used as control. Tissue specimens were analyzed for fibromuscular, lipid and calcium contents. The expressions of MMP-9, TIMP-1 and COX-2 in each plaque were quantified. Results Fifty-eight percent of all carotid plaques were classified as Type VI according to the American Heart Association Committee on Vascular Lesions. The control carotid arteries all were classified as Type III. The median percentage of fibromuscular tissue was significantly greater in group II compared to group I (p < 0.05). The median percentage of lipid tissue had a tendency to be greater in group I than in group II (p = 0.057). The percentages of calcification were similar among the two groups. MMP-9 protein expression levels were significantly higher in group II and in the control group when compared with group I (p < 0.001). TIMP-1 expression levels were significantly higher in the control group and in group II when compared to group I, with statistical difference between control group and group I (p = 0.010). COX-2 expression levels did not differ among groups. There was no statistical correlation between MMP-9, COX-2, and TIMP-1 levels and fibrous tissue. Conclusions MMP-9 and TIMP-1 are present in all stages of atherosclerotic plaque progression, from normal tissue to advanced lesions. When sections of a plaque are analyzed without preselection, MMP-9 concentration is higher in normal tissues and asymptomatic surgical specimens than in symptomatic specimens, and TIMP-1 concentration is higher in normal tissue than in symptomatic specimens. PMID:21457581

An apple oligogalactan potentiates the growth inhibitory effect of celecoxib on colorectal cancer.

PubMed

Li, Yuhua; Niu, Yinbo; Sun, Yang; Mei, Lin; Zhang, Bangle; Li, Qian; Liu, Li; Zhang, Rong; Chen, Jianfa; Mei, Qibing

2014-01-01

Multiple studies have indicated that selective cyclooxygenase-2 (COX-2) inhibitors possess clinically chemopreventive and preclinically anticancer activities. Their long-term use, however, may be limited by the cardiovascular toxicity. This study tried to investigate whether an apple oligogalactan (AOG) could enhance the growth inhibitory effect of celecoxib on colorectal cancer. Caco-2 and HT-29 cell lines were exposed to different concentrations of AOG (0-1 g/L), celecoxib (0-25 μmol/L), and their combination. COX-2 levels were assessed by reverse transcription PCR and Western blot. COX-2 activity was evaluated by measuring prostaglandin E2 concentration. A colitis-associated colorectal cancer (CACC) mouse model was used to determine the effect of the combination in vivo. AOG (0.1-0.5 g/L) could potentiate the inhibitory effect of physiologic doses of celecoxib (5 μmol/L) on cell growth and decrease COX-2 expressions both at RNA and protein levels. In vivo, the combination (2.5% AOG plus 0.04% celecoxib, w/w) prevented against CACC in mice effectively. Our data indicate that AOG could potentiate the growth inhibitory effect of celecoxib on colorectal cancer both in vitro and in vivo through influencing the expression and function of COX-2 and phosphorylation of MAPKs, which suggests a new possible combinatorial strategy in colorectal cancer therapy.

Triptolide inhibits COX-2 expression by regulating mRNA stability in TNF-{alpha}-treated A549 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Lixin; Zhang, Shuang; Jiang, Zhenzhou

2011-12-09

Highlights: Black-Right-Pointing-Pointer Triptolide inhibited COX-2 expression and the half-life of COX-2 mRNA is decreased. Black-Right-Pointing-Pointer The HuR protein shuttling from nucleus to cytoplasm is inhibited by triptolide. Black-Right-Pointing-Pointer Triptolide inhibited 3 Prime -UTR fluorescence reporter gene activity. Black-Right-Pointing-Pointer COX-2 mRNA binding to HuR is decreased by triptolide in pull-down experiments. -- Abstract: Cyclooxygenase-2 (COX-2) over-expression is frequently associated with human non-small-cell lung cancer (NSCLC) and involved in tumor proliferation, invasion, angiogenesis and resistance to apoptosis. In the present study, the effects of triptolide on COX-2 expression in A549 cells were investigated and triptolide was found to inhibit TNF-{alpha}-induced COX-2 expression.more » In our further studies, it was found that triptolide decreased the half-life of COX-2 mRNA dramatically and that it inhibited 3 Prime -untranslated region (3 Prime -UTR) fluorescence reporter gene activity. Meanwhile, triptolide inhibited the HuR shuttling from nucleus to cytoplasm. After triptolide treatment, decreased COX-2 mRNA in pull-down experiments with anti-HuR antibodies was observed, indicating that the decreased cytoplasmic HuR is responsible for the decreased COX-2 mRNA. Taken together, our results provided evidence for the first time that triptolide inhibited COX-2 expression by COX-2 mRNA stability modulation and post-transcriptional regulation. These results provide a novel mechanism of action for triptolide which may be important in the treatment of lung cancer.« less

COX2 Inhibition Reduces Aortic Valve Calcification In Vivo

PubMed Central

Wirrig, Elaine E.; Gomez, M. Victoria; Hinton, Robert B.; Yutzey, Katherine E.

2016-01-01

Objective Calcific aortic valve disease (CAVD) is a significant cause of morbidity and mortality, which affects approximately 1% of the US population and is characterized by calcific nodule formation and stenosis of the valve. Klotho-deficient mice were used to study the molecular mechanisms of CAVD as they develop robust aortic valve (AoV) calcification. Through microarray analysis of AoV tissues from klotho-deficient and wild type mice, increased expression of the gene encoding cyclooxygenase 2/COX2 (Ptgs2) was found. COX2 activity contributes to bone differentiation and homeostasis, thus the contribution of COX2 activity to AoV calcification was assessed. Approach and Results In klotho-deficient mice, COX2 expression is increased throughout regions of valve calcification and is induced in the valvular interstitial cells (VICs) prior to calcification formation. Similarly, COX2 expression is increased in human diseased AoVs. Treatment of cultured porcine aortic VICs with osteogenic media induces bone marker gene expression and calcification in vitro, which is blocked by inhibition of COX2 activity. In vivo, genetic loss of function of COX2 cyclooxygenase activity partially rescues AoV calcification in klotho-deficient mice. Moreover, pharmacologic inhibition of COX2 activity in klotho-deficient mice via celecoxib-containing diet reduces AoV calcification and blocks osteogenic gene expression. Conclusions COX2 expression is upregulated in CAVD and its activity contributes to osteogenic gene induction and valve calcification in vitro and in vivo. PMID:25722432

Cyclooxygenase-2 expression is related to nuclear grade in ductal carcinoma in situ and is increased in its normal adjacent epithelium

NASA Technical Reports Server (NTRS)

Shim, Veronica; Gauthier, Mona L.; Sudilovsky, Daniel; Mantei, Kristin; Chew, Karen L.; Moore, Dan H.; Cha, Imok; Tlsty, Thea D.; Esserman, Laura J.

2003-01-01

Cyclooxygenase-2 (COX-2) is emerging as an important cancer biomarker and is now an experimental target for solid tumor treatment.However, no study has exclusively focused on COX-2 expression in early lesions such as ductal carcinoma in situ (DCIS). We examined COX-2 expression by immunohistochemistry in 46 cases of women undergoing surgical resection for DCIS. We found that COX-2 expression was detected in 85% of all DCIS specimens, with increased COX-2 staining correlating with higher nuclear grade. Strikingly, COX-2 staining intensity in the normal adjacent epithelium was stronger than in the DCIS lesion itself. Our observations demonstrate that COX-2 is up-regulated in the normal adjacent epithelium and supports the hypothesis that the surrounding epithelial tissue is part of the disease process in DCIS.

Cyclo-oxygenase isozymes in mucosal ulcergenic and functional responses following barrier disruption in rat stomachs.

PubMed

Hirata, T; Ukawa, H; Yamakuni, H; Kato, S; Takeuchi, K

1997-10-01

1. We examined the effects of selective and nonselective cyclo-oxygenase (COX) inhibitors on various functional changes in the rat stomach induced by topical application of taurocholate (TC) and investigated the preferential role of COX isozymes in these responses. 2. Rat stomachs mounted in ex vivo chambers were perfused with 50 mM HCl and transmucosal potential difference (p.d.), mucosal blood flow (GMBF), luminal acid loss and luminal levels of prostaglandin E2 (PGE2) were measured before, during and after exposure to 20 mM TC. 3. Mucosal application of TC in control rats caused a reduction in p.d., followed by an increase of luminal acid loss and GMBF, and produced only minimal damage in the mucosa 2 h later. Pretreatment with indomethacin (10 mg kg[-1], s.c.), a nonselective COX-1 and COX-2 inhibitor, attenuated the gastric hyperaemic response caused by TC without affecting p.d. and acid loss, resulting in haemorrhagic lesions in the mucosa. In contrast, selective COX-2 inhibitors, such as NS-398 and nimesulide (10 mg kg[-1], s.c.), had no effect on any of the responses induced by TC and did not cause gross damage in the mucosa. 4. Luminal PGE2 levels were markedly increased during and after exposure to TC and this response was significantly inhibited by indomethacin but not by either NS-398 or nimesulide. The expression of COX-1-mRNA was consistently detected in the gastric mucosa before and after TC treatment, while a faint expression of COX-2-mRNA was detected only 2 h after TC treatment. 5. Both NS-398 and nimesulide significantly suppressed carrageenan-induced rat paw oedema, similar to indomethacin. 6. These results confirmed a mediator role for prostaglandins in the gastric hyperaemic response following TC-induced barrier disruption, and suggest that COX-1 but not COX-2 is a key enzyme in maintaining 'housekeeping' functions in the gastric mucosa under both normal and adverse conditions.

Microglia cyclooxygenase-2 activity in experimental gliomas: possible role in cerebral edema formation.

PubMed

Badie, Behnam; Schartner, Jill M; Hagar, Aaron R; Prabakaran, Sakthivel; Peebles, Todd R; Bartley, Becky; Lapsiwala, Samir; Resnick, Daniel K; Vorpahl, Jessica

2003-02-01

Cerebral edema is responsible for significant morbidity and mortality in patients harboring malignant gliomas. To examine the role of inflammatory cells in brain edema formation, we studied the expression cyclooxygenase (COX)-2, a key enzyme in arachidonic acid metabolism, by microglia in the C6 rodent glioma model. The expression of COX-2 in primary microglia cultures obtained from intracranial rat C6 gliomas was examined using reverse transcription-PCR, Western analysis, and prostaglandin E(2) (PGE(2)) enzyme immunoassay. Blood-tumor barrier permeability was studied in the same tumor model using magnetic resonance imaging. In contrast to C6 glioma cells, microglia isolated from intracranial C6 tumors produced high levels of PGE(2) through a COX-2-dependent pathway. To test whether the observed microglia COX-2 activity played a role in brain edema formation in gliomas, tumor-bearing rats were treated with rofecoxib, a selective COX-2 inhibitor. Rofecoxib was as effective as dexamethasone in decreasing the diffusion of contrast material into the brain parenchyma (P = 0.01, rofecoxib versus control animals), suggesting a reduction in blood-tumor barrier permeability. These findings suggest that glioma-infiltrating microglia are a major source of PGE(2) production through the COX-2 pathway and support the use of COX-2 inhibitors as possible alternatives to glucocorticoids in the treatment of peritumoral edema in patients with malignant brain tumors.

Cyclooxygenase-2 expression in non-metastatic triple-negative breast cancer patients.

PubMed

Mosalpuria, Kailash; Hall, Carolyn; Krishnamurthy, Savitri; Lodhi, Ashutosh; Hallman, D Michael; Baraniuk, Mary S; Bhattacharyya, Anirban; Lucci, Anthony

2014-09-01

Triple-negative breast cancer (TNBC) is characterised by lack of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor (HER)2/neu gene amplification. TNBC patients typically present at a younger age, with a larger average tumor size, higher grade and higher rates of lymph node positivity compared to patients with ER/PR-positive tumors. Cyclooxygenase (COX)-2 regulates the production of prostaglandins and is overexpressed in a variety of solid tumors. In breast cancer, the overexpression of COX-2 is associated with indicators of poor prognosis, such as lymph node metastasis, poor differentiation and large tumor size. Since both TNBC status and COX-2 overexpression are known poor prognostic markers in primary breast cancer, we hypothesized that the COX-2 protein is overexpressed in the primary tumors of TNBC patients. The purpose of this study was to determine whether there exists an association between TNBC status and COX-2 protein overexpression in primary breast cancer. We prospectively evaluated COX-2 expression levels in primary tumor samples obtained from 125 patients with stage I-III breast cancer treated between February, 2005 and October, 2007. Information on clinicopathological factors was obtained from a prospective database. Baseline tumor characteristics and patient demographics were compared between TNBC and non-TNBC patients using the Chi-square and Fisher's exact tests. In total, 60.8% of the patients were classified as having ER-positive tumors, 51.2% were PR-positive, 14.4% had HER-2/neu amplification and 28.0% were classified as TNBC. COX-2 overexpression was found in 33.0% of the patients. TNBC was associated with COX-2 overexpression (P=0.009), PR expression (P=0.048) and high tumor grade (P=0.001). After adjusting for age, menopausal status, body mass index (BMI), lymph node status and neoadjuvant chemotherapy (NACT), TNBC was an independent predictor of COX-2 overexpression (P=0.01). In conclusion, the association between TNBC and COX-2 overexpression in operable breast cancer supports further investigation into COX-2-targeted therapy for patients with TNBC.

Immunohistochemical localization of cyclooxygenase isoforms in the organ of Corti and the spiral ganglion cells of guinea pig cochlea.

PubMed

Ziegler, E A; Brieger, J; Heinrich, U R; Mann, W J

2004-01-01

Prostaglandins have been used in experimental models and clinical studies for the therapy of sudden hearing loss and tinnitus with conflicting results. However, little is known about the rate-limiting enzymes of prostaglandin synthesis in the inner ear, the generally constitutively expressed cyclooxygenase 1 (COX-1) and the distress-inducible cyclooxygenase 2 (COX-2). To extend our knowledge concerning the physiological expression and localization of these two enzymes, immunohistochemical stainings of the guinea pig cochlea were performed. Light microscopical analysis revealed a homogenous distribution of COX-1 within nearly all cell types of the organ of Corti, but no COX-1 expression in the cuticular plates of pillar cells. COX-2 was found to be expressed in all cell types, with much stronger expression in Hensen cells, neighboring Deiters cells and cuticular plates of outer hair cells. Both COX-1 and COX-2 immunoreactions were also found in the spiral ganglion. We conclude that both COX subtypes are expressed in the guinea pig cochlea under physiological conditions. The prominent expression of the distress-inducible COX-2 isoform in cell types under mechanical stress during noise reception might support the hypothesis of a cytoprotective function of COX products in hearing and in cellular stress situations like intense noise exposure. Copyright (c) 2004 S. Karger AG, Basel.

COX-2 expression in papillary thyroid carcinoma (PTC) in cytological material obtained by fine needle aspiration biopsy (FNAB)

PubMed Central

2011-01-01

Background COX-2 is an enzyme isoform that catalyses the formation of prostanoids from arachidonic acid. An increased COX-2 gene expression is believed to participate in carcinogenesis. Recent studies have shown that COX-2 up-regulation is associated with the development of numerous neoplasms, including skin, colorectal, breast, lung, stomach, pancreas and liver cancers. COX-2 products stimulate endothelial cell proliferation and their overexpression has been demonstrated to be involved in the mechanism of decreased resistance to apoptosis. Suppressed angiogenesis was found in experimental animal studies as a consequence of null mutation of COX-2 gene in mice. Despite the role of COX-2 expression remains a subject of numerous studies, its participation in carcinogenesis or the thyroid cancer progression remains unclear. Methods Twenty three (23) patients with cytological diagnosis of PTC were evaluated. After FNAB examination, the needle was washed out with a lysis buffer and the obtained material was used for COX-2 expression estimation. Total RNA was isolated (RNeasy Micro Kit), and RT reactions were performed. β-actin was used as endogenous control. Relative COX-2 expression was assessed in real-time PCR reactions by an ABI PRISM 7500 Sequence Detection System, using the ΔΔCT method. Results COX-2 gene expression was higher in patients with PTC, when compared to specimens from patients with non-toxic nodular goitre (NTG). Conclusions The preliminary results may indicate COX-2 role in thyroid cancer pathogenesis, however the observed variability in results among particular subjects requires additional clinical data and tumor progression analysis. PMID:21214962

COX-2 expression in papillary thyroid carcinoma (PTC) in cytological material obtained by fine needle aspiration biopsy (FNAB).

PubMed

Krawczyk-Rusiecka, Kinga; Wojciechowska-Durczyńska, Katarzyna; Cyniak-Magierska, Anna; Adamczewski, Zbigniew; Gałecka, Elżbieta; Lewiński, Andrzej

2011-01-10

COX-2 is an enzyme isoform that catalyses the formation of prostanoids from arachidonic acid. An increased COX-2 gene expression is believed to participate in carcinogenesis. Recent studies have shown that COX-2 up-regulation is associated with the development of numerous neoplasms, including skin, colorectal, breast, lung, stomach, pancreas and liver cancers. COX-2 products stimulate endothelial cell proliferation and their overexpression has been demonstrated to be involved in the mechanism of decreased resistance to apoptosis. Suppressed angiogenesis was found in experimental animal studies as a consequence of null mutation of COX-2 gene in mice. Despite the role of COX-2 expression remains a subject of numerous studies, its participation in carcinogenesis or the thyroid cancer progression remains unclear. Twenty three (23) patients with cytological diagnosis of PTC were evaluated. After FNAB examination, the needle was washed out with a lysis buffer and the obtained material was used for COX-2 expression estimation. Total RNA was isolated (RNeasy Micro Kit), and RT reactions were performed. β-actin was used as endogenous control. Relative COX-2 expression was assessed in real-time PCR reactions by an ABI PRISM 7500 Sequence Detection System, using the ΔΔCT method. COX-2 gene expression was higher in patients with PTC, when compared to specimens from patients with non-toxic nodular goitre (NTG). The preliminary results may indicate COX-2 role in thyroid cancer pathogenesis, however the observed variability in results among particular subjects requires additional clinical data and tumor progression analysis.

Prostacyclin synthase expression and epigenetic regulation in nonsmall cell lung cancer.

PubMed

Cathcart, Mary-Clare; Gray, Steven G; Baird, Anne-Marie; Boyle, Elaine; Gately, Kathy; Kay, Elaine; Cummins, Robert; Pidgeon, Graham P; O'Byrne, Kenneth J

2011-11-15

Prostacyclin synthase (PGIS) metabolizes prostaglandin H(2), into prostacyclin. This study aimed to determine the expression profile of PGIS in nonsmall cell lung cancer (NSCLC) and examine potential mechanisms involved in PGIS regulation. PGIS expression was examined in human NSCLC and matched controls by reverse transcriptase polymerase chain reaction (RT-PCR), Western analysis, and immunohistochemistry. A 204-patient NSCLC tissue microarray was stained for PGIS and cyclooxygenase 2 (COX2) expression. Staining intensity was correlated with clinical parameters. Epigenetic mechanisms underpinning PGIS promoter expression were examined using RT-PCR, methylation-specific PCR, and chromatin immunoprecipitation analysis. PGIS expression was reduced/absent in human NSCLC protein samples (P < .0001), but not mRNA relative to matched controls. PGIS tissue expression was higher in squamous cell carcinoma (P = .004) and in male patients (P < .05). No significant correlation of PGIS or COX2 expression with overall patient survival was observed, although COX2 was prognostic for short-term (2-year) survival (P < .001). PGIS mRNA expression was regulated by DNA CpG methylation and histone acetylation in NSCLC cell lines, with chromatin remodeling taking place directly at the PGIS gene. PGIS mRNA expression was increased by both demethylation agents and histone deacetylase inhibitors. Protein levels were unaffected by demethylation agents, whereas PGIS protein stability was negatively affected by histone deacetylase inhibitors. PGIS protein expression is reduced in NSCLC, and does not correlate with overall patient survival. PGIS expression is regulated through epigenetic mechanisms. Differences in expression patterns between mRNA and protein levels suggest that PGIS expression and protein stability are regulated post-translationally. PGIS protein stability may have an important therapeutic role in NSCLC. Copyright © 2011 American Cancer Society.

Ethanol extract of Angelica gigas inhibits croton oil-induced inflammation by suppressing the cyclooxygenase - prostaglandin pathway

PubMed Central

Shin, Sunhee; Joo, Seong Soo; Park, Dongsun; Jeon, Jeong Hee; Kim, Tae Kyun; Kim, Jeong Seon; Park, Sung Kyeong

2010-01-01

The anti-inflammatory effects of an ethanol extract of Angelica gigas (EAG) were investigated in vitro and in vivo using croton oil-induced inflammation models. Croton oil (20 µg/mL) up-regulated mRNA expression of cyclooxygenase (COX)-I and COX-II in the macrophage cell line, RAW 264.7, resulting in the release of high concentrations of prostaglandin E2 (PGE2). EAG (1~10 µg/mL) markedly suppressed croton oil-induced COX-II mRNA expression and PGE2 production. Application of croton oil (5% in acetone) to mouse ears caused severe local erythema, edema and vascular leakage, which were significantly attenuated by oral pre-treatment with EAG (50~500 mg/kg). Croton oil dramatically increased blood levels of interleukin (IL)-6 and PGE2 without affecting tumor-necrosis factor (TNF)-α and nitric oxide (NO) levels. EAG pre-treatment remarkably lowered IL-6 and PGE2, but did not alter TNF-α or NO concentrations. These results indicate that EAG attenuates inflammatory responses in part by blocking the COX-PGE2 pathway. Therefore, EAG could be a promising candidate for the treatment of inflammatory diseases. PMID:20195064

Targeted deletion and lipidomic analysis identify epithelial cell COX-2 as a major driver of chemically induced skin cancer.

PubMed

Jiao, Jing; Ishikawa, Tomo-O; Dumlao, Darren S; Norris, Paul C; Magyar, Clara E; Mikulec, Carol; Catapang, Art; Dennis, Edward A; Fischer, Susan M; Herschman, Harvey R

2014-11-01

Pharmacologic and global gene deletion studies demonstrate that cyclooxygenase-2 (PTGS2/COX-2) plays a critical role in DMBA/TPA-induced skin tumor induction. Although many cell types in the tumor microenvironment express COX-2, the cell types in which COX-2 expression is required for tumor promotion are not clearly established. Here, cell type-specific Cox-2 gene deletion reveals a vital role for skin epithelial cell COX-2 expression in DMBA/TPA tumor induction. In contrast, myeloid Cox-2 gene deletion has no effect on DMBA/TPA tumorigenesis. The infrequent, small tumors that develop on mice with an epithelial cell-specific Cox-2 gene deletion have decreased proliferation and increased cell differentiation properties. Blood vessel density is reduced in tumors with an epithelial cell-specific Cox-2 gene deletion, compared with littermate control tumors, suggesting a reciprocal relationship in tumor progression between COX-2-expressing tumor epithelial cells and microenvironment endothelial cells. Lipidomics analysis of skin and tumors from DMBA/TPA-treated mice suggests that the prostaglandins PGE2 and PGF2α are likely candidates for the epithelial cell COX-2-dependent eicosanoids that mediate tumor progression. This study both illustrates the value of cell type-specific gene deletions in understanding the cellular roles of signal-generating pathways in complex microenvironments and emphasizes the benefit of a systems-based lipidomic analysis approach to identify candidate lipid mediators of biologic responses. Cox-2 gene deletion demonstrates that intrinsic COX-2 expression in initiated keratinocytes is a principal driver of skin carcinogenesis; lipidomic analysis identifies likely prostanoid effectors. ©2014 American Association for Cancer Research.

Involvement of PI3K/Akt and p38 MAPK in the induction of COX-2 expression by bacterial lipopolysaccharide in murine adrenocortical cells.

PubMed

Mercau, M E; Astort, F; Giordanino, E F; Martinez Calejman, C; Sanchez, R; Caldareri, L; Repetto, E M; Coso, O A; Cymeryng, C B

2014-03-25

Previous studies from our laboratory demonstrated the involvement of COX-2 in the stimulation of steroid production by LPS in murine adrenocortical Y1 cells, as well as in the adrenal cortex of male Wistar rats. In this paper we analyzed signaling pathways involved in the induction of this key regulatory enzyme in adrenocortical cells and demonstrated that LPS triggers an increase in COX-2 mRNA levels by mechanisms involving the stimulation of reactive oxygen species (ROS) generation and the activation of p38 MAPK and Akt, in addition to the previously demonstrated increase in NFκB activity. In this sense we showed that: (1) inhibition of p38 MAPK or PI3K/Akt (pharmacological or molecular) prevented the increase in COX-2 protein levels by LPS, (2) LPS induced p38 MAPK and Akt phosphorylation, (3) antioxidant treatment blocked the effect of LPS on p38 MAPK phosphorylation and in COX-2 protein levels, (4) PI3K inhibition with LY294002 prevented p38 MAPK phosphorylation and, (5) the activity of an NFκB reporter was decreased by p38 MAPK or PI3K inhibition. These results suggest that activation of both p38 MAPK and PI3K/Akt pathways promote the stimulation of NFκB activity and that PI3K/Akt activity might regulate both p38 MAPK and NFκB signaling pathways. In summary, in this study we showed that in adrenal cells, LPS induces COX-2 expression by activating p38 MAPK and PI3K/Akt signaling pathways and that both pathways converge in the modulation of NFκB transcriptional activity. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Caffeic acid, a phenolic phytochemical in coffee, directly inhibits Fyn kinase activity and UVB-induced COX-2 expression

PubMed Central

Kang, Nam Joo; Lee, Ki Won; Shin, Bong Jik; Jung, Sung Keun; Hwang, Mun Kyung; Bode, Ann M.; Heo, Yong-Seok; Dong, Zigang

2009-01-01

Caffeic acid (3,4-dihydroxycinnamic acid) is a well-known phenolic phytochemical present in many foods, including coffee. Recent studies suggested that caffeic acid exerts anticarcinogenic effects, but little is known about the underlying molecular mechanisms and specific target proteins. In this study, we found that Fyn, one of the members of the non-receptor protein tyrosine kinase family, was required for ultraviolet (UV) B-induced cyclooxygenase-2 (COX-2) expression, and caffeic acid suppressed UVB-induced skin carcinogenesis by directly inhibiting Fyn kinase activity. Caffeic acid more effectively suppressed UVB-induced COX-2 expression and subsequent prostaglandin E2 production in JB6 P+ mouse skin epidermal (JB6 P+) cells compared with chlorogenic acid (5-O-caffeoylquinic acid), an ester of caffeic acid with quinic acid. Data also revealed that caffeic acid more effectively induced the downregulation of COX-2 expression at the transcriptional level mediated through the inhibition of activator protein-1 (AP-1) and nuclear factor-κB transcription activity compared with chlorogenic acid. Fyn kinase activity was suppressed more effectively by caffeic acid than by chlorogenic acid, and downstream mitogen-activated protein kinases (MAPKs) were subsequently blocked. Pharmacological Fyn kinase inhibitor (3-(4-chlorophenyl)1-(1,1-dimethylethyl)-1H-pyrazolo[3,4-d]pyrimidin-4-amine and leflunomide) data also revealed that Fyn is involved in UVB-induced COX-2 expression mediated through the phosphorylation of MAPKs in JB6 P+ cells. Pull-down assays revealed that caffeic acid directly bound with Fyn and non-competitively with adenosine triphosphate. In vivo data from mouse skin also supported the idea that caffeic acid suppressed UVB-induced COX-2 expression by blocking Fyn kinase activity. These results suggested that this compound could act as a potent chemopreventive agent against skin cancer. PMID:19073879

Increased dietary sodium induces COX2 expression by activating NFκB in renal medullary interstitial cells.

PubMed

He, Wenjuan; Zhang, Min; Zhao, Min; Davis, Linda S; Blackwell, Timothy S; Yull, Fiona; Breyer, Matthew D; Hao, Chuan-Ming

2014-02-01

High salt diet induces renal medullary cyclooxygenase 2 (COX2) expression. Selective blockade of renal medullary COX2 activity in rats causes salt-sensitive hypertension, suggesting a role for renal medullary COX2 in maintaining systemic sodium balance. The present study characterized the cellular location of COX2 induction in the kidney of mice following high salt diet and examined the role of NFκB in mediating this COX2 induction in response to increased dietary salt. High salt diet (8 % NaCl) for 3 days markedly increased renal medullary COX2 expression in C57Bl/6 J mice. Co-immunofluorescence using a COX2 antibody and antibodies against aquaporin-2, ClC-K, aquaporin-1, and CD31 showed that high salt diet-induced COX2 was selectively expressed in renal medullary interstitial cells. By using NFκB reporter transgenic mice, we observed a sevenfold increase of luciferase activity in the renal medulla of the NFκB-luciferase reporter mice following high salt diet, and a robust induction of enhanced green fluorescent protein (EGFP) expression mainly in renal medullary interstitial cells of the NFκB-EGFP reporter mice following high salt diet. Treating high salt diet-fed C57Bl/6 J mice with selective IκB kinase inhibitor IMD-0354 (8 mg/kg bw) substantially suppressed COX2 induction in renal medulla, and also significantly reduced urinary prostaglandin E2 (PGE2). These data therefore suggest that renal medullary interstitial cell NFκB plays an important role in mediating renal medullary COX2 expression and promoting renal PGE2 synthesis in response to increased dietary sodium.

Celecoxib plus chemoradiotherapy for locally advanced rectal cancer: a phase II TCOG study.

PubMed

Wang, Ling-Wei; Hsiao, Chin-Fu; Chen, William Tzu-Liang; Lee, Hao-Hsien; Lin, Tzu-Chen; Chen, Hung-Chang; Chen, Hong-Hwa; Chien, Chun-Ru; Lin, Tze-Yi; Liu, Tsang-Wu

2014-05-01

To report the results of a phase II trial combining celecoxib and preoperative chemoradiotherapy (CRT) for locally advanced rectal cancer. Patients with clinical stage II or III rectal cancer were treated with radiotherapy of 44 Gy in 22 fractions. Concurrent chemotherapy consisted of oral tegafur-uracil and folinate on days 1-30 and 38-65. Celecoxib (400 mg/day) given from days 1 to 65. Surgery was done on day 70. The expression of cyclooxygenase 2 (COX-2) in tumor tissues was evaluated microscopically as a prognostic factor. From 2008 to 2011, 53 patients completed CRT+ celecoxib therapy and 47 received radical surgery. Grade 3 diarrhea developed in 5 (9%). Grade 4 anemia was seen in 2 (4%). Pathological complete response (pCR) was seen in 6 (13%). T or N downstaging found in 38 (81%). Sphincter preservation was achieved in 77% of low-positioned tumors. Patients with tumors expressing high-level COX-2 after CRT + celecoxib treatment had inferior pelvic control (P = 0.01), disease-free survival (P = 0.04), and overall survival (P = 0.03) than those with low-level expression. Celecoxib can be safely combined with preoperative CRT for rectal cancer. More intensified adjuvant therapy may be considered for tumors expressing high-level COX-2 after CRT and surgery. © 2013 Wiley Periodicals, Inc.

Protective effects of levamisole, acetylsalicylic acid, and α-tocopherol against dioxin toxicity measured as the expression of AhR and COX-2 in a chicken embryo model.

PubMed

Gostomska-Pampuch, Kinga; Ostrowska, Alicja; Kuropka, Piotr; Dobrzyński, Maciej; Ziółkowski, Piotr; Kowalczyk, Artur; Łukaszewicz, Ewa; Gamian, Andrzej; Całkosiński, Ireneusz

2017-04-01

Polychlorinated dibenzo-p-dioxins and dibenzofurans (dioxins) are classed as persistent organic pollutants and have adverse effects on multiple functions within the body. Dioxins are known carcinogens, immunotoxins, and teratogens. Dioxins are transformed in vivo, and interactions between the products and the aryl hydrocarbon receptor (AhR) lead to the formation of proinflammatory and toxic metabolites. The aim of this study was to determine whether α-tocopherol (vitamin E), acetylsalicylic acid (ASA), and levamisole can decrease the amount of damage caused by dioxins. Fertile Hubbard Flex commercial line chicken eggs were injected with solutions containing 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) or containing TCDD and the test compounds. The chicken embryos and organs were analyzed after 7 and 13 days. The levels at which AhR and cyclooxygenase-2 (COX-2) proteins (which are induced during inflammation) were expressed were evaluated by performing immunohistochemical analyses on embryos treated with TCDD alone or with TCDD and the test compounds. TCDD caused developmental disorders and increased AhR and COX-2 expression in the chicken embryo tissues. Vitamin E, levamisole, ASA, and ASA plus vitamin E inhibited AhR and COX-2 expression in embryos after 7 days and decreased AhR and COX-2 expression in embryos after 13 days. ASA, levamisole, and ASA plus vitamin E weakened the immune response and prevented multiple organ changes. Vitamin E was not fully protective against developmental changes in the embryos.

Ethanol enhances arsenic-induced cyclooxygenase-2 expression via both NFAT and NF-κB signalings in colorectal cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Lei; Hitron, John Andrew; Toxicology and Cancer Biology, College of Medicine, University of Kentucky, Lexington, KY 40536

Arsenic is a known carcinogen to humans, and chronic exposure to environmental arsenic is a worldwide health concern. As a dietary factor, ethanol carries a well-established risk for malignancies, but the effects of co-exposure to arsenic and ethanol on tumor development are not well understood. In the present study, we hypothesized that ethanol would enhance the function of an environmental carcinogen such as arsenic through increase in COX-2 expression. Our in vitro results show that ethanol enhanced arsenic-induced COX-2 expression. We also show that the increased COX-2 expression associates with intracellular ROS generation, up-regulated AKT signaling, with activation of bothmore » NFAT and NF-κB pathways. We demonstrate that antioxidant enzymes have an inhibitory effect on arsenic/ethanol-induced COX-2 expression, indicating that the responsive signaling pathways from co-exposure to arsenic and ethanol relate to ROS generation. In vivo results also show that co-exposure to arsenic and ethanol increased COX-2 expression in mice. We conclude that ethanol enhances arsenic-induced COX-2 expression in colorectal cancer cells via both the NFAT and NF-κB pathways. These results imply that, as a common dietary factor, ethanol ingestion may be a compounding risk factor for arsenic-induced carcinogenesis/cancer development. - Highlights: • Arsenic is able to induce Cox-2 expression in colorectal cancer cells. • Ethanol, a diet nutritional factor, could enhance arsenic-induced Cox-2. • The up-regulation of Cox-2 via both NFAT and NF-κB activities.« less

Nutritionally relevant concentrations of resveratrol and hydroxytyrosol mitigate oxidative burst of human granulocytes and monocytes and the production of pro-inflammatory mediators in LPS-stimulated RAW 264.7 macrophages.

PubMed

Bigagli, Elisabetta; Cinci, Lorenzo; Paccosi, Sara; Parenti, Astrid; D'Ambrosio, Mario; Luceri, Cristina

2017-02-01

The health benefits of bio-active phenolic compounds have been largely investigated in vitro at concentrations which exceed those reachable in vivo. We investigated and compared the anti-inflammatory effects of resveratrol, hydroxytyrosol and oleuropein at physiologically relevant concentrations by using in vitro models of inflammation. Human granulocytes and monocytes were stimulated with phorbol myristate acetate (PMA) and the ability of resveratrol, hydroxytyrosol and oleuropein to inhibit the oxidative burst and CD11b expression was measured. Nitric oxide (NO), prostaglandin E2 (PGE2) levels, COX-2, iNOS, TNFα, IL-1β and miR-146a expression and activation of the transcription factor Nrf2 were evaluated in macrophages RAW 264.7 stimulated with LPS (1μg/ml) for 18h, exposed to resveratrol, hydroxytyrosol and oleuropein (5 and 10μM). Synergistic effects were explored as well, together with the levels of PGE2, COX-2 and IL-1β expression in macrophages after 6h of LPS stimulation. PGE2 and COX-2 expression were also assessed on human monocytes. All the tested compounds inhibited granulocytes oxidative burst in a concentration dependent manner and CD11b expression was also significantly counteracted by resveratrol and hydroxytyrosol. The measurement of oxidative burst in human monocytes produced similar effects being resveratrol more active. Hydroxytyrosol and resveratrol inhibited the production of NO and PGE2 but did not reduce iNOS, TNFα or IL-1β gene expression in LPS-stimulated RAW 264.7 for 18h. Resveratrol slightly decreased COX-2 expression after 18h but not after 6h, but reduced PGE2 levels after 6h. Resveratrol and hydroxytyrosol 10μM induced NRf2 nuclear translocation and reduced miR-146a expression in LPS treated RAW 264.7. Overall, we reported an anti-inflammatory effect of resveratrol and hydroxytyrosol at low, nutritionally relevant concentrations, involving the inhibition of granulocytes and monocytes activation, the modulation of miR-146a expression and the activation of Nrf2. A regular dietary intake of resveratrol and hydroxytyrosol may be a useful complementary strategy to control inflammatory diseases. Copyright © 2016 Elsevier B.V. All rights reserved.

Identification of novel Cyclooxygenase-2-dependent genes in Helicobacter pylori infection in vivo

PubMed Central

Walduck, Anna K; Weber, Matthias; Wunder, Christian; Juettner, Stefan; Stolte, Manfred; Vieth, Michael; Wiedenmann, Bertram; Meyer, Thomas F; Naumann, Michael; Hoecker, Michael

2009-01-01

Background Helicobacter pylori is a crucial determining factor in the pathogenesis of benign and neoplastic gastric diseases. Cyclooxygenase-2 (Cox-2) is the inducible key enzyme of arachidonic acid metabolism and is a central mediator in inflammation and cancer. Expression of the Cox-2 gene is up-regulated in the gastric mucosa during H. pylori infection but the pathobiological consequences of this enhanced Cox-2 expression are not yet characterized. The aim of this study was to identify novel genes down-stream of Cox-2 in an in vivo model, thereby identifying potential targets for the study of the role of Cox- 2 in H. pylori pathogenesis and the initiation of pre- cancerous changes. Results Gene expression profiles in the gastric mucosa of mice treated with a specific Cox-2 inhibitor (NS398) or vehicle were analysed at different time points (6, 13 and 19 wk) after H. pylori infection. H. pylori infection affected the expression of 385 genes over the experimental period, including regulators of gastric physiology, proliferation, apoptosis and mucosal defence. Under conditions of Cox-2 inhibition, 160 target genes were regulated as a result of H. pylori infection. The Cox-2 dependent subset included those influencing gastric physiology (Gastrin, Galr1), epithelial barrier function (Tjp1, connexin45, Aqp5), inflammation (Icam1), apoptosis (Clu) and proliferation (Gdf3, Igf2). Treatment with NS398 alone caused differential expression of 140 genes, 97 of which were unique, indicating that these genes are regulated under conditions of basal Cox-2 expression. Conclusion This study has identified a panel of novel Cox-2 dependent genes influenced under both normal and the inflammatory conditions induced by H. pylori infection. These data provide important new links between Cox-2 and inflammatory processes, epithelial repair and integrity. PMID:19317916

Curcumin inhibits VEGF-mediated angiogenesis in human intestinal microvascular endothelial cells through COX-2 and MAPK inhibition.

PubMed

Binion, D G; Otterson, M F; Rafiee, P

2008-11-01

Angiogenesis, the growth of new blood vessels, is a critical homeostatic mechanism which regulates vascular populations in response to physiological requirements and pathophysiological demand, including chronic inflammation and cancer. The importance of angiogenesis in gastrointestinal chronic inflammation and cancer has been defined, as antiangiogenic therapy has demonstrated benefit in models of inflammatory bowel disease and colon cancer treatment. Curcumin is a natural product undergoing evaluation for the treatment of chronic inflammation, including inflammatory bowel disease (IBD). The effect of curcumin on human intestinal angiogenesis is not defined. The antiangiogenic effect of curcumin on in vitro angiogenesis was examined using primary cultures of human intestinal microvascular endothelial cells (HIMECs), stimulated with vascular endothelial growth factor (VEGF). Curcumin inhibited proliferation, cell migration and tube formation in HIMECs induced by VEGF. Activation of HIMECs by VEGF resulted in enhanced expression of cyclo-oxygenase-2 (COX-2) mRNA, protein and prostaglandin E(2) (PGE(2)) production. Pretreatment of HIMECs with 10 microM curcumin as well as 1 microM NS398, a selective inhibitor of COX-2, resulted in inhibition of COX-2 at the mRNA and protein level and PGE(2) production. Similarly COX-2 expression in HIMECs was significantly inhibited by Jun N-terminal kinase (JNK; SP600125) and p38 mitogen-activated protein kinase (MAPK; SB203580) inhibitors and was reduced by p44/42 MAPK inhibitor (PD098059). Taken together, these data demonstrate an important role for COX-2 in the regulation of angiogenesis in HIMECs via MAPKs. Moreover, curcumin inhibits microvascular endothelial cell angiogenesis through inhibition of COX-2 expression and PGE(2) production, suggesting that this natural product possesses antiangiogenic properties, which warrants further investigation as adjuvant treatment of IBD and cancer.

Effects of C-phycocyanin and Spirulina on Salicylate-Induced Tinnitus, Expression of NMDA Receptor and Inflammatory Genes

PubMed Central

Hwang, Juen-Haur; Chen, Jin-Cherng; Chan, Yin-Ching

2013-01-01

Effects of C-phycocyanin (C-PC), the active component of Spirulina platensis water extract on the expressions of N-methyl D-aspartate receptor subunit 2B (NR2B), tumor necrosis factor–α (TNF-α), interleukin-1β (IL-1β), and cyclooxygenase type 2 (COX-2) genes in the cochlea and inferior colliculus (IC) of mice were evaluated after tinnitus was induced by intraperitoneal injection of salicylate. The results showed that 4-day salicylate treatment (unlike 4-day saline treatment) caused a significant increase in NR2B, TNF-α, and IL-1β mRNAs expression in the cochlea and IC. On the other hand, dietary supplementation with C-PC or Spirulina platensis water extract significantly reduced the salicylate-induced tinnitus and down-regulated the mRNAs expression of NR2B, TNF-α, IL-1β mRNAs, and COX-2 genes in the cochlea and IC of mice. The changes of protein expression levels were generally correlated with those of mRNAs expression levels in the IC for above genes. PMID:23533584

Role of interleukin-1beta and tumor necrosis factor-alpha-dependent expression of cyclooxygenase-2 mRNA in thermal hyperalgesia induced by chronic inflammation in mice.

PubMed

Narita, M; Shimamura, M; Imai, S; Kubota, C; Yajima, Y; Takagi, T; Shiokawa, M; Inoue, T; Suzuki, M; Suzuki, T

2008-03-18

The present study investigated whether the endogenous pro-inflammatory cytokines [interleukin (IL)-1beta and tumor necrosis factor-alpha (TNF-alpha)]-dependent expression of cyclooxygenase-2 (COX-2) mRNA within the spinal cord could be involved in the development of chronic inflammatory pain-like behaviors in mice. We demonstrated that the expression of COX-2 mRNA on the ipsilateral side of the spinal cord was significantly increased 6 h and 3 days after intraplantar injection of complete Freund's adjuvant (CFA), compared with the expression in saline-treated mice. In addition, the chronic pain-like behaviors following CFA injection were markedly suppressed by repeated intrathecal (i.t.) pre-treatment with the COX-2 inhibitor etodolac, but not with the COX-1 inhibitor mofezolac. The cytosolic level of the activated form of nuclear factor-kappa B (NF-kappaB), which is a major contributor to the induction of COX-2, on the ipsilateral side of the mouse spinal cord was also increased compared with that in the saline-treated mice. The key finding in the present study was that a single i.t. injection with either IL-1beta or TNF-alpha induced a marked increase in spinal COX-2 mRNA and persistent thermal hyperalgesia in mice. Furthermore, CFA-induced hypersensitivity to inflammatory pain was significantly reduced by repeated i.t. pre-injection of the recombinant Fc chimera of IL-1 receptor I or soluble TNF receptor I, which sequesters endogenous IL-1beta or TNF-alpha, respectively. In contrast, the expression of spinal COX-2 mRNA in CFA-treated mice was similar to that in saline-treated mice at 7 days after CFA injection. The present findings strongly indicate the early intrathecal use of the COX-2 inhibitor for the relief of chronic inflammatory pain. Furthermore, together with the result in a previous study that pro-inflammatory cytokines lead to stimulation of a NF-kappaB-dependent transcriptional pathway, these findings suggest that a spinal cytokine/NF-kappaB/COX-2 pathway may play an important role in the development, but not maintenance, of chronic pain following peripheral tissue inflammation.

Radiation Therapy Overcomes Adverse Prognostic Role of Cyclooxygenase-2 Expression on Reed-Sternberg Cells in Early Hodgkin Lymphoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mestre, Francisco; Gutiérrez, Antonio, E-mail: antoniom.gutierrez@ssib.es; Rodriguez, Jose

Purpose: To analyze the role of radiation therapy (RT) on the adverse prognostic influence of cyclooxygenase-2 (COX-2) expression on Reed-Sternberg (RS) cells, in the setting of early Hodgkin lymphoma (HL) treated with ABVD (adriamycin, vinblastine, bleomycin, dacarbazine). Methods and Materials: In the present study we retrospectively investigated the prognostic value of COX-2 expression in a large (n=143), uniformly treated early HL population from the Spanish Network of HL using tissue microarrays. Univariate and multivariate analyses were done, including the most recognized clinical variables and the potential role of administration of adjuvant RT. Results: Median age was 31 years; the expression of COX-2more » defined a subgroup with significantly worse prognosis. Considering COX-2{sup +} patients, those who received RT had significantly better 5-year progression-free survival (PFS) (80% vs 54% if no RT; P=.008). In contrast, COX-2{sup −} patients only had a modest, nonsignificant benefit from RT in terms of 5-year PFS (90% vs 79%; P=.13). When we compared the outcome of patients receiving RT considering the expression of COX-2 on RS cells, we found a nonsignificant 10% difference in terms of PFS between COX-2{sup +} and COX-2{sup −} patients (P=.09), whereas the difference between the 2 groups was important (25%) in patients not receiving RT (P=.04). Conclusions: Cyclooxygenase-2 RS cell expression is an adverse independent prognostic factor in early HL. Radiation therapy overcomes the worse prognosis associated with COX-2 expression on RS cells, acting in a chemotherapy-independent way. Cyclooxygenase-2 RS cell expression may be useful for determining patient candidates with early HL to receive consolidation with RT.« less

Effects of the estrous cycle, pregnancy and interferon tau on expression of cyclooxygenase two (COX-2) in ovine endometrium

PubMed Central

Kim, Seokwoon; Choi, Youngsok; Spencer, Thomas E; Bazer, Fuller W

2003-01-01

In sheep, the uterus produces luteolytic pulses of prostaglandin F2α (PGF) on Days 15 to 16 of estrous cycle to regress the corpus luteum (CL). These PGF pulses are produced by the endometrial lumenal epithelium (LE) and superficial ductal glandular epithelium (sGE) in response to binding of pituitary and/or luteal oxytocin to oxytocin receptors (OTR) and liberation of arachidonic acid, the precursor of PGF. Cyclooxygenase-one (COX-1) and COX-2 are rate-limiting enzymes in PGF synthesis, and COX-2 is the major form expressed in ovine endometrium. During pregnancy recognition, interferon tau (IFNτ), produced by the conceptus trophectoderm, acts in a paracrine manner to suppress development of the endometrial epithelial luteolytic mechanism by inhibiting transcription of estrogen receptor α (ERα) (directly) and OTR (indirectly) genes. Conflicting studies indicate that IFNτ increases, decreases or has no effect on COX-2 expression in bovine and ovine endometrial cells. In Study One, COX-2 mRNA and protein were detected solely in endometrial LE and sGE of both cyclic and pregnant ewes. During the estrous cycle, COX-2 expression increased from Days 10 to 12 and then decreased to Day 16. During early pregnancy, COX-2 expression increased from Days 10 to 12 and remained higher than in cyclic ewes. In Study Two, intrauterine infusion of recombinant ovine IFNτ in cyclic ewes from Days 11 to 16 post-estrus did not affect COX-2 expression in the endometrial epithelium. These results clearly indicate that IFNτ has no effect on expression of the COX-2 gene in the ovine endometrium. Therefore, antiluteolytic effects of IFNτ are to inhibit ERα and OTR gene transcription, thereby preventing endometrial production of luteolytic pulses of PGF. Indeed, expression of COX-2 in the endometrial epithelia as well as conceptus is likely to have a beneficial regulatory role in implantation and development of the conceptus. PMID:12956885

Mercury exposure induces proinflammatory enzymes in vascular fibroblasts.

PubMed

Millán Longo, Alberto; Montero Saiz, Óscar; Sarró Fuente, Claudia; Aguado Martínez, Andrea; Salaices Sánchez, Mercedes

Previous studies show that mercury exposure increases cardiovascular risk, although the underlying cellular mechanisms have still not been fully studied. The aim of this project is to study, in vascular fibroblasts (VF), the effect of HgCl 2 exposure on the expression of enzymes involved in the synthesis of prostanoids and reactive oxygen species (ROS). These molecules have been shown to participate in the inflammatory response associated with cardiovascular diseases. Adventitial VF cultures of Sprague-Dawley rat aortas, shown to be α-actin negative by immunofluorescence, were exposed to HgCl 2 (0.05-5μg/mL) for 48h. mRNA and protein levels of cyclooxygenase-2 (COX-2), microsomal prostaglandin E synthase 1 (mPGES-1), thromboxane A 2 synthase (TXAS), NADPH oxidase 1 (NOX-1), and 4 (NOX-4) where analyzed using qRT-PCR and western blot, respectively. NOX activity was determined by chemiluminescence. HgCl 2 exposure increased COX-2, mPGES-1, TXAS, and NOX-1 expression and NOX activity, and decreased NOX-4 expression. The increase in NOX-1 and COX-2 expression was abolished by the treatment with inhibitors of COX-2 (10μM celecoxib) and NOX (300μM apocynin, 0.5μM ML-171). 1) HgCl 2 increases the expression of pro-inflammatory enzymes involved in ROS and prostanoid synthesis in VF. 2) There is a reciprocal regulation between COX-2 and NOX-1 pathways. 3) These effects can contribute to explain the increase in cardiovascular risk associated to mercury. Copyright © 2017 Sociedad Española de Arteriosclerosis. Publicado por Elsevier España, S.L.U. All rights reserved.

Expression of COX-2 and bcl-2 in oral lichen planus lesions and lichenoid reactions

PubMed Central

Arreaza, Alven J; Rivera, Helen; Correnti, María

2014-01-01

Oral lichen planus and lichenoid reactions are autoimmune type inflammatory conditions of the oral mucosa with similar clinical and histological characteristics. Recent data suggest that oral lichenoid reactions (OLR) present a greater percentage of malignant transformation than oral lichen planus (OLP). Objective To compare the expression of bcl-2 and COX-2 in OLP and OLR. Methods The study population consisted of 65 cases; 34 cases diagnosed as OLR and 31 as OLP. A retrospective study was done, and bcl-2 and COX-2 expression was semiquantitatively analysed. Results Fifty-three per cent (18/34) of the ORL samples tested positive for COX-2, whereas in the OLP group, 81% of the samples (25/31) immunostained positive for COX-2. The Fisher’s exact test for the expression of COX-2 revealed that there are significant differences between the two groups, P = 0.035. With respect to the expression of the bcl-2 protein, 76% (26/34) of the samples were positive in OLR, while 97% (30/31) were positive in the group with OLP. The Fisher’s exact test for the expression of bcl-2 revealed that there are significant statistical differences between the two groups, P = 0.028. Conclusions The expression of bcl-2 and COX-2 was more commonly expressed in OLP when compared with OLR. PMID:24834112

Injured nerve-derived COX2/PGE2 contributes to the maintenance of neuropathic pain in aged rats.

PubMed

Ma, Weiya; Chabot, Jean-Guy; Vercauteren, Freya; Quirion, Remi

2010-07-01

Neuropathic pain (NeP) is a debilitating disease afflicting mostly the aged population. Inflammatory responses in injured nerves play a pivotal role in the pathogenesis of NeP. Injured nerve derived cyclooxygenase 2/prostaglandin E2 (COX2/PGE2) contributes to the genesis of NeP at the early stage in young rats. Here we show that COX2/PGE2 is involved in the maintenance of NeP at a chronic stage in aged rats. Eighteen months after partial sciatic nerve ligation (PSNL), NeP remained prominent in aged rats. COX2 expressing macrophages and PGE2 levels were increased in injured nerves. PGE2 receptors (EP1 and EP4) and pain-related ion channel transient receptor potential vanilloid-1 (TRPV1) were increased in the ipsilateral dorsal root ganglion (DRG) neurons of aged PSNL rats. Perineural injection of a selective COX2 inhibitor NS-398 relieved NeP, reversed PSNL increased expression of EP1, EP4 and TRPV1 and suppressed the levels of pain-related peptide substance P and calcitonin gene-related peptide in DRG neurons. These data suggest that injured nerve-derived PGE2 contributes to the maintenance of NeP at the chronic stage in aged rats. Chronically facilitating the synthesis of pain-related molecules in nociceptive DRG neurons is a novel mechanism underpinning the contribution of PGE2. Copyright 2008 Elsevier Inc. All rights reserved.

Extract from Nandina domestica inhibits lipopolysaccharide-induced cyclooxygenase-2 expression in human pulmonary epithelial A549 cells.

PubMed

Ueki, Takuro; Akaishi, Tatsuhiro; Okumura, Hidenobu; Abe, Kazuho

2012-01-01

Extract from fruits of Nandina domestica THUNBERG (NDE) has been used to improve cough and breathing difficulty in Japan for many years. To explore whether NDE may alleviate respiratory inflammation, we investigated its effect on expression of cyclooxygenase-2 (COX-2) and production of prostaglandin E₂ (PGE₂) in human pulmonary epithelial A549 cells in culture. Treatment with lipopolysaccharide (LPS; 6 µg/mL) resulted in an increase of COX-2 expression and PGE₂ production in A549 cells. Both the LPS-induced COX-2 expression and PGE₂ production were significantly inhibited by NDE (1-10 µg/mL) in a concentration-dependent manner. NDE did not affect COX-1 expression nor COX activity. These results suggest that NDE downregulates LPS-induced COX-2 expression and inhibits PGE₂ production in pulmonary epithelial cells. Furthermore, higenamine and nantenine, two major constituents responsible for tracheal relaxing effect of NDE, did not mimic the inhibitory effect of NDE on LPS-induced COX-2 expression in A549 cells. To identify active constituent(s) of NDE responsible for the anti-inflammatory effect, NDE was introduced in a polyaromatic absorbent resin column and stepwise eluted to yield water fraction, 20% methanol fraction, 40% methanol fraction, 99.8% methanol fraction, and 99.5% acetone fraction. However, none of these five fractions alone inhibited LPS-induced COX-2 expression. On the other hand, exclusion of water fraction from NDE abolished the inhibitory effect of NDE on LPS-induced COX-2 expression. These results suggest that constituent(s) present in water fraction is required but not sufficient for the anti-inflammatory activity of NDE, which may result from interactions among multiple constituents.

The role of COX-2 and Nrf2/ARE in anti-inflammation and antioxidative stress: Aging and anti-aging.

PubMed

Luo, Cheng; Urgard, Egon; Vooder, Tõnu; Metspalu, Andres

2011-08-01

Oxidative stress and inflammation are constant features of many chronic diseases and complications, and have been linked to carcinogenesis. Cyclooxygenase 2 (COX-2), a rate-limiting enzyme for the synthesis of prostaglandins, plays important roles in physiology and pathology, but has been a source of controversy within the scientific and clinical community. However, recent work has shown that nuclear factor erythroid-2-related factor-2 (Nrf2) confers protection against oxidative stress. Furthermore, COX-2-dependent electrophile oxo-derivative (EFOX) molecules have been shown to act as anti-inflammatory mediators via activation of the Nrf2-dependent antioxidant response element (ARE). These studies have provided more insight into COX-2-mediated events. The function of all tissues, especially epithelial and endothelial tissues, declines with age, leading to the production of reactive oxygen species (ROS). COX-2 expression increases with aging in most tissues, due in part to ROS, chemical reactions, physical shearing, and dietary molecules. Here we discuss new findings related to COX-2 inflammatory and anti-inflammatory responses. Taken together, we hypothesize that COX-2 levels increase during the aging process because increasing levels of ROSs necessitate the involvement of COX-2-dependent EFOXs for anti-inflammation and Nrf2/ARE signaling for antioxidation. We also propose that COX-2 may act as an intrinsic biological aging clock due to its role in balancing inflammatory and anti-inflammatory responses. Copyright © 2011 Elsevier Ltd. All rights reserved.

Changes in gene expression induced by histamine, fexofenadine and osthole: Expression of histamine H1 receptor, COX-2, NF-κB, CCR1, chemokine CCL5/RANTES and interleukin-1β in PBMC allergic and non-allergic patients.

PubMed

Kordulewska, Natalia Karolina; Kostyra, Elżbieta; Cieślińska, Anna; Matysiewicz, Michał; Fiedorowicz, Ewa; Sienkiewicz-Szłapka, Edyta

2017-03-01

Fexofenadine (FXF) is a third-generation antihistamine drug and osthole is assumed as a natural antihistamine alternative. This paper compares results of histamine, FXF and osthole impact on HRH-1, COX-2, NF-κB-p50, CCR1 mRNA expression. We also measured mRNA expression of IL-1β and CCL5/RANTES in incubated peripheral blood mononuclear cells (PBMC) to compared how histamine, FXF and osthole had influence on expression level and interacts on product secretion. The purpose was to investigate expression pattern in asthma PBMC. The cultures were treated 72h with FXF and osthole. We measured mRNA expression of histamine HRH-1, COX-2, NF-κB-p50, CCR1, IL-1β and CCL5/RANTES with Real-Time PCR (RT-PCR). The present study suggest that osthole may be a potential inhibitor of histamine H 1 receptor activity. We also demonstrated that cells cultured with histamine increase COX-2 mRNA expression and osthole reduce it. Allergy remains one of the most common chronic diseases in Europe and it is rapidly approaching epidemic proportions; with current predictions estimating that the number of allergy-afflicted will equal the healthy population by 2020. It is therefore paramount to find new pharmaceuticals which successfully combat allergic disease. Copyright © 2016 Elsevier GmbH. All rights reserved.

DPPC regulates COX-2 expression in monocytes via phosphorylation of CREB

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morris, R.H.K.; Tonks, A.J.; Jones, K.P.

2008-05-23

The major phospholipid in pulmonary surfactant dipalmitoyl phosphatidylcholine (DPPC) has been shown to modulate inflammatory responses. Using human monocytes, this study demonstrates that DPPC significantly increased PGE{sub 2} (P < 0.05) production by 2.5-fold when compared to untreated monocyte controls. Mechanistically, this effect was concomitant with an increase in COX-2 expression which was abrogated in the presence of a COX-2 inhibitor. The regulation of COX-2 expression was independent of NF-{kappa}B activity. Further, DPPC increased the phosphorylation of the cyclic AMP response element binding protein (CREB; an important nuclear transcription factor important in regulating COX-2 expression). In addition, we also showmore » that changing the fatty acid groups of PC (e.g. using L-{alpha}-phosphatidylcholine {beta}-arachidonoyl-{gamma}-palmitoyl (PAPC)) has a profound effect on the regulation of COX-2 expression and CREB activation. This study provides new evidence for the anti-inflammatory activity of DPPC and that this activity is at least in part mediated via CREB activation of COX-2.« less

COX2/mPGES1/PGE2 pathway regulates PD-L1 expression in tumor-associated macrophages and myeloid-derived suppressor cells

PubMed Central

Prima, Victor; Kaliberova, Lyudmila N.; Kaliberov, Sergey; Curiel, David T.; Kusmartsev, Sergei

2017-01-01

In recent years, it has been established that programmed cell death protein ligand 1 (PD-L1)–mediated inhibition of activated PD-1+ T lymphocytes plays a major role in tumor escape from immune system during cancer progression. Lately, the anti–PD-L1 and –PD-1 immune therapies have become an important tool for treatment of advanced human cancers, including bladder cancer. However, the underlying mechanisms of PD-L1 expression in cancer are not fully understood. We found that coculture of murine bone marrow cells with bladder tumor cells promoted strong expression of PD-L1 in bone marrow–derived myeloid cells. Tumor-induced expression of PD-L1 was limited to F4/80+ macrophages and Ly-6C+ myeloid-derived suppressor cells. These PD-L1–expressing cells were immunosuppressive and were capable of eliminating CD8 T cells in vitro. Tumor-infiltrating PD-L1+ cells isolated from tumor-bearing mice also exerted morphology of tumor-associated macrophages and expressed high levels of prostaglandin E2 (PGE2)-forming enzymes microsomal PGE2 synthase 1 (mPGES1) and COX2. Inhibition of PGE2 formation, using pharmacologic mPGES1 and COX2 inhibitors or genetic overexpression of PGE2-degrading enzyme 15-hydroxyprostaglandin dehydrogenase (15-PGDH), resulted in reduced PD-L1 expression. Together, our study demonstrates that the COX2/mPGES1/PGE2 pathway involved in the regulation of PD-L1 expression in tumor-infiltrating myeloid cells and, therefore, reprogramming of PGE2 metabolism in tumor microenvironment provides an opportunity to reduce immune suppression in tumor host. PMID:28096371

Cyclooxygenase-2 expression in the eyes of cats with and without uveitis.

PubMed

Sim, Zhi Hui; Pinard, Chantale L; Plattner, Brandon L; Bienzle, Dorothee

2018-01-01

OBJECTIVE To characterize the distribution and intensity of cyclooxygenase (COX)-2 expression in the eyes of cats with and without uveitis and to determine whether COX-2 expression is correlated with severity of inflammation. SAMPLES Archived ocular tissue specimens from 51 cats with and 10 cats without ocular disease. PROCEDURES Specimens from only 1 eye were evaluated for each cat. Specimens were stained with H&E stain or immunohistochemical stain for detection of COX-2 and reviewed. For each eye, the type, severity, and distribution of inflammation and the distribution and intensity of COX-2 expression were determined for the uvea and other ocular tissues. Correlation between COX-2 expression and inflammation severity was also assessed. RESULTS COX-2 was not expressed in any nondiseased eye. Of the 51 diseased eyes, 20 had histologic evidence of lymphocytic-plasmacytic uveitis, 13 had neutrophilic uveitis, 11 had diffuse iris melanoma with uveitis, and 7 had diffuse iris melanoma without uveitis. Of the 44 eyes with uveitis, COX-2 was detected in the uvea of 16, including 11 eyes with lymphocytic-plasmacytic uveitis, 4 with neutrophilic uveitis, and 1 with diffuse iris melanoma-induced uveitis. Inflammation was severe, moderate, or mild in 10, 5, and 1 of those eyes, respectively. Cyclooxygenase-2 was detected in the cornea of 21 eyes with uveitis and 1 eye with diffuse iris melanoma without uveitis. Uveitis severity was positively correlated with COX-2 expression in both the uvea and cornea. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that COX-2 is an inflammatory mediator in feline uveitis but not diffuse iris melanoma.

MicroRNA-144 is regulated by CP2 and decreases COX-2 expression and PGE2 production in mouse ovarian granulosa cells

PubMed Central

Zhou, Jiawei; Lei, Bin; Li, Huanan; Zhu, Lihua; Wang, Lei; Tao, Hu; Mei, Shuqi; Li, Fenge

2017-01-01

Mammalian folliculogenesis is a complex process in which primordial follicles develop into pre-ovulatory follicles, followed by ovulation to release mature oocytes. In this study, we explored the role of miR-144 in ovulation. miR-144 was one of the differentially expressed microRNAs, which showed 5.59-fold changes, in pre-ovulatory ovarian follicles between Large White and Chinese Taihu sows detected by Solexa deep sequencing. We demonstrated that overexpression of miR-144 significantly decreased the luciferase reporter activity under the control of the cyclooxygenase-2 (COX-2) or mothers against decapentaplegic homologue 4 (Smad4) 3'-untranslated region (3'-UTR) and suppressed COX-2 and Smad4 expression. In contrast, a miR-144 inhibitor increased COX-2 and Smad4 expression in mouse granulosa cells (mGCs). Meanwhile, Smad4 upregulated COX-2 expression, but this effect was abolished when the mGCs were treated with the transforming growth factor beta signalling pathway inhibitor SB431542. Moreover, luciferase reporter, chromatin immunoprecipitation and electrophoretic mobility shift assay results showed that the transcription factor CP2 upregulated miR-144 expression, which partially contributed to the suppression of COX-2 in mGCs. Both CP2 and miR-144 alter prostaglandin E2 (PGE2) production by regulating COX-2 expression. In addition, miR-144 regulated mGC apoptosis and affected follicular atresia, but these activities did not appear to be through COX-2 and Smad4. Taken together, we revealed an important CP2/miR-144/COX-2/PGE2/ovulation pathway in mGCs. PMID:28182010

Coordinate up-regulation of low-density lipoprotein receptor and cyclo-oxygenase-2 gene expression in human colorectal cells and in colorectal adenocarcinoma biopsies

NASA Technical Reports Server (NTRS)

Lum, D. F.; McQuaid, K. R.; Gilbertson, V. L.; Hughes-Fulford, M.

1999-01-01

Many colorectal cancers have high levels of cyclo-oxygenase 2 (COX-2), an enzyme that metabolizes the essential fatty acids into prostaglandins. Since the low-density lipoprotein receptor (LDLr) is involved in the uptake of essential fatty acids, we studied the effect of LDL on growth and gene regulation in colorectal cancer cells. DiFi cells grown in lipoprotein-deficient sera (LPDS) grew more slowly than cells with LDL. LDLr antibody caused significant inhibition of tumor cell growth but did not affect controls. In addition, LDL uptake did not change in the presence of excess LDL, suggesting that ldlr mRNA lacks normal feedback regulation in some colorectal cancers. Analysis of the ldlr mRNA showed that excess LDL in the medium did not cause down-regulation of the message even after 24 hr. The second portion of the study examined the mRNA expression of ldlr and its co-regulation with cox-2 in normal and tumor specimens from patients with colorectal adenocarcinomas. The ratio of tumor:paired normal mucosa of mRNA expression of ldlr and of cox-2 was measured in specimens taken during colonoscopy. ldlr and cox-2 transcripts were apparent in 11 of 11 carcinomas. There was significant coordinate up-regulation both of ldlr and of cox-2 in 6 of 11 (55%) tumors compared with normal colonic mucosa. There was no up-regulation of cox-2 without concomitant up-regulation of ldlr. These data suggest that the LDLr is abnormally regulated in some colorectal tumors and may play a role in the up-regulation of cox-2. Copyright 1999 Wiley-Liss, Inc.

Suppression of IL-1beta-induced COX-2 expression by trichostatin A (TSA) in human endometrial stromal cells.

PubMed

Wu, Yan; Guo, Sun-Wei

2007-11-01

Over-production of cyclooxygenase-2 (COX-2) plays an important role in the positive feedback loop that leads to proliferation and inflammation in endometriosis. Following our observation that histone deacetylase inhibitors (HDACIs) trichostatin A (TSA) and valproic acid (VPA) can suppress proliferation of endometrial stromal cells, we sought to determine whether TSA suppresses IL-1beta-induced COX-2 expression in endometrial stromal cells. In vitro study using a recently established immortalized endometrial stromal cell line. The stromal cells were pretreated with TSA before stimulation with IL-1beta, and COX-2 gene and protein expression was measured by real-time quantitative RT-PCR and Western blot analysis, respectively. IL-1beta stimulated COX-2 expression in a concentration-dependent manner in endometrial stromal cells. The induced COX-2 gene and protein expression were suppressed by TSA pretreatment. TSA suppresses IL-1beta-induced COX-2 gene and protein expression in endometrial stromal cells. This finding, coupled with the findings that TSA and another HDACI, valproic acid, suppress proliferation and induce cell cycle arrest, suggests that HDACIs are a promising class of compound that has therapeutic potential for endometriosis.

Cyclooxygenase-2 inhibitors modulate skin aging in a catalytic activity-independent manner

PubMed Central

Lee, Mi Eun; Kim, So Ra; Lee, Seungkoo; Jung, Yu-Jin; Choi, Sun Shim; Kim, Woo Jin

2012-01-01

It has been proposed that the pro-inflammatory catalytic activity of cyclooxygenase-2 (COX-2) plays a key role in the aging process. However, it remains unclear whether the COX-2 activity is a causal factor for aging and whether COX-2 inhibitors could prevent aging. We here examined the effect of COX-2 inhibitors on aging in the intrinsic skin aging model of hairless mice. We observed that among two selective COX-2 inhibitors and one non-selective COX inhibitor studied, only NS-398 inhibited skin aging, while celecoxib and aspirin accelerated skin aging. In addition, NS-398 reduced the expression of p53 and p16, whereas celecoxib and aspirin enhanced their expression. We also found that the aging-modulating effect of the inhibitors is closely associated with the expression of type I procollagen and caveolin-1. These results suggest that pro-inflammatory catalytic activity of COX-2 is not a causal factor for aging at least in skin and that COX-2 inhibitors might modulate skin aging by regulating the expression of type I procollagen and caveolin-1. PMID:22771771

COX-2 contributes to LPS-induced Stat3 activation and IL-6 production in microglial cells

PubMed Central

Zhu, Jie; Li, Shuzhen; Zhang, Yue; Ding, Guixia; Zhu, Chunhua; Huang, Songming; Zhang, Aihua; Jia, Zhanjun; Li, Mei

2018-01-01

Many stimuli including lipopolysaccharide (LPS) could activate microglial cells to subsequently cause inflammatory nerve injury. However, the mechanism of LPS-induced neuroinflammation in microglial cells is still elusive. Thus, the present study was undertaken to examine the role of COX-2 in mediating the activation of Stat3 and the production of IL-6 in BV2 cells challenged with LPS. After 24 h treatment, LPS dose-dependently enhanced COX-2 expression at both mRNA and protein levels. Meanwhile, IL-6 with other inflammatory cytokines including IL-1β, TNF-α, and MCP-1 were similarly enhanced by LPS. Then a specific COX-2 inhibitor (NS-398) was administered to BV2 before LPS treatment. Significantly, COX-2 inhibition suppressed the upregulation of IL-6 at both mRNA and protein levels in line with the trend blockade on IL-1β, TNF-α, and MCP-1. Stat3 drives proinflammatory signaling pathways and contributes to IL-6 production via a transcriptional mechanism in many diseases. Here we found that inhibition of COX-2 entirely blocked LPS-induced Stat3 phosphorylation, which might contribute to the blockade of IL-6 production to some extent. Meanwhile, COX-2 siRNA approach largely reproduced the phenotypes shown by specific COX-2 inhibitor in LPS-treated BV2 cells. Together, these findings suggested that COX-2 might contribute to LPS-induced IL-6 production possibly through activating Stat3 signaling pathway in microglial cells. PMID:29636886

Enhanced cyclooxygenase-2 expression levels and metalloproteinase 2 and 9 activation by Hexachlorobenzene in human endometrial stromal cells.

PubMed

Chiappini, Florencia; Bastón, Juan Ignacio; Vaccarezza, Agustina; Singla, José Javier; Pontillo, Carolina; Miret, Noelia; Farina, Mariana; Meresman, Gabriela; Randi, Andrea

2016-06-01

Hexachlorobenzene (HCB) is an organochlorine pesticide that induces toxic reproductive effects in laboratory animals. It is a dioxin-like compound and a weak ligand of the aryl hydrocarbon receptor (AhR). Endometriosis is characterized by the presence of functional endometrial tissues outside the uterine cavity. Experimental studies indicate that exposure to organochlorines can interfere with both hormonal regulation and immune function to promote endometriosis. Altered expression of metalloproteinases (MMPs) in patients with endometriosis, suggests that MMPs may play a critical role. In the endometriotic lesions, prostaglandin E2 (PGE2) produced by cyclooxygenase-2 (COX-2), binds to its EP4 receptor (EP4), and via c-Src kinase induces MMPs activation, promoting endometriosis. We examined the HCB action on MMP-2 and MMP-9 activities and expression, COX-2 levels, PGE2 signaling, and the AhR involvement in HCB-induced effects. We have used different in vitro models: (1) human endometrial stromal cell line T-HESC, (2) primary cultures of Human Uterine Fibroblast (HUF), and (3) primary cultures of endometrial stromal cells from eutopic endometrium of control (CESC) and subjects with endometriosis (EESC). Our results show that HCB enhances MMP-2 and MMP-9 activities in T-HESC, HUF and ESC cells. The MMP-9 levels were elevated in all models, while the MMP-2 expression only increased in ESC cells. HCB enhanced COX-2 and EP4 expression, PGE2 secretion and the c-Src kinase activation in T-HESC. Besides, we observed that AhR is implicated in these HCB-induced effects. In conclusion, our results show that HCB exposure could contribute to endometriosis development, affecting inflammation and invasion parameters of human endometrial cells. Copyright © 2016 Elsevier Inc. All rights reserved.

Flavocoxid, a dual inhibitor of cyclooxygenase and 5-lipoxygenase, blunts pro-inflammatory phenotype activation in endotoxin-stimulated macrophages

PubMed Central

Altavilla, D; Squadrito, F; Bitto, A; Polito, F; Burnett, BP; Di Stefano, V; Minutoli, L

2009-01-01

Background and purpose: The flavonoids, baicalin and catechin, from Scutellaria baicalensis and Acacia catechu, respectively, have been used for various clinical applications. Flavocoxid is a mixed extract containing baicalin and catechin, and acts as a dual inhibitor of cyclooxygenase (COX) and 5-lipoxygenase (LOX) enzymes. The anti-inflammatory activity, measured by protein and gene expression of inflammatory markers, of flavocoxid in rat peritoneal macrophages stimulated with Salmonella enteritidis lipopolysaccharide (LPS) was investigated. Experimental approach: LPS-stimulated (1 µg·mL−1) peritoneal rat macrophages were co-incubated with different concentrations of flavocoxid (32–128 µg·mL−1) or RPMI medium for different incubation times. Inducible COX-2, 5-LOX, inducible nitric oxide synthase (iNOS) and inhibitory protein κB-α (IκB-α) levels were evaluated by Western blot analysis. Nuclear factor κB (NF-κB) binding activity was investigated by electrophoretic mobility shift assay. Tumour necrosis factor-α (TNF-α) gene and protein expression were measured by real-time polymerase chain reaction and enzyme-linked immunosorbent assay respectively. Finally, malondialdehyde (MDA) and nitrite levels in macrophage supernatants were evaluated. Key results: LPS stimulation induced a pro-inflammatory phenotype in rat peritoneal macrophages. Flavocoxid (128 µg·mL−1) significantly inhibited COX-2 (LPS = 18 ± 2.1; flavocoxid = 3.8 ± 0.9 integrated intensity), 5-LOX (LPS = 20 ± 3.8; flavocoxid = 3.1 ± 0.8 integrated intensity) and iNOS expression (LPS = 15 ± 1.1; flavocoxid = 4.1 ± 0.4 integrated intensity), but did not modify COX-1 expression. PGE2 and LTB4 levels in culture supernatants were consequently decreased. Flavocoxid also prevented the loss of IκB-α protein (LPS = 1.9 ± 0.2; flavocoxid = 7.2 ± 1.6 integrated intensity), blunted increased NF-κB binding activity (LPS = 9.2 ± 2; flavocoxid = 2.4 ± 0.7 integrated intensity) and the enhanced TNF-α mRNA levels (LPS = 8 ± 0.9; flavocoxid = 1.9 ± 0.8 n-fold/β-actin) induced by LPS. Finally, flavocoxid decreased MDA, TNF and nitrite levels from LPS-stimulated macrophages. Conclusion and implications: Flavocoxid might be useful as a potential anti-inflammatory agent, acting at the level of gene and protein expression. PMID:19681869

Kyungheechunggan-Tang-01, a New Herbal Medication, Suppresses LPS-Induced Inflammatory Responses through JAK/STAT Signaling Pathway in RAW 264.7 Macrophages

PubMed Central

Han, Hee-Soo; Shin, Ji-Sun; Inn, Kyung-Soo; Lee, Jang-Hoon; Park, Geonha

2017-01-01

Medicinal plants have been used as alternative therapeutic tools to alleviate inflammatory diseases. The objective of this study was to evaluate anti-inflammatory properties of Kyungheechunggan-tang- (KCT-) 01, KCT-02, and Injinchunggan-tang (IJCGT) as newly developed decoctions containing 3–11 herbs in LPS-induced macrophages. KCT-01 showed the most potent inhibitory effects on LPS-induced NO, PGE2, TNF-α, and IL-6 production among those three herbal formulas. In addition, KCT-01 significantly inhibited LPS-induced iNOS and COX-2 at protein levels and expression of iNOS, COX-2, TNF-α, and IL-6 at mRNA levels. Molecular data revealed that KCT-01 attenuated the activation of JAK/STAT signaling cascade without affecting NF-κB or AP-1 activation. In ear inflammation induced by croton oil, KCT-01 significantly reduced edema, MPO activity, expression levels of iNOS and COX-2, and STAT3 phosphorylation in ear tissues. Taken together, our findings suggest that KCT-01 can downregulate the expression of proinflammatory genes by inhibiting JAK/STAT signaling pathway under inflammatory conditions. This study provides useful data for further exploration and application of KCT-01 as a potential anti-inflammatory medicine. PMID:29348772

Neuroimmune response to endogenous and exogenous pyrogens is differently modulated by sex steroids.

PubMed

Mouihate, A; Pittman, Q J

2003-06-01

The objective of this study was to explore whether and how ovarian hormones interact with the febrile response to pyrogens. Estrogen and progesterone treatment of ovariectomized rats was associated with a reduction in lipopolysaccharide (LPS)-induced fever, compared with ovariectomized controls. LPS-fever reduction was accompanied by reduced levels of the inducible cyclooxygenase-2 (COX-2) protein expression in the hypothalamus as well as reduced plasma levels of IL-1beta. The amount of LPS-induced IL-6 in the plasma was not affected by ovarian hormone replacement. In contrast, hypothalamic COX-2 expression in response to intraperitoneal injection of IL-1beta was potentiated by the ovarian hormone replacement. IL-1beta induced a moderate increase in plasma levels of IL-6 that was suppressed by ovarian hormone replacement. These data suggest that ovarian hormone replacement attenuated the proinflammatory response to LPS by suppressing the LPS-induced IL-1beta production and COX-2 expression in the hypothalamus. The markedly different action of ovarian hormones on IL-1beta and LPS effects suggests that this sex hormone modulation of the immune response is a function of the nature of infection and provides further evidence that LPS actions are different from those of IL-1beta.

Azilsartan increases levels of IL-10, down-regulates MMP-2, MMP-9, RANKL/RANK, Cathepsin K and up-regulates OPG in an experimental periodontitis model.

PubMed

Araújo, Aurigena Antunes de; Varela, Hugo; Brito, Gerly Anne de Castro; Medeiros, Caroline Addison Carvalho Xavier de; Araújo, Lorena de Souza; do Nascimento, José Heriberto Oliveira; de Araújo Júnior, Raimundo Fernandes

2014-01-01

The aim of this study was to evaluate the effects of azilsartan (AZT) on bone loss, inflammation, and the expression of matrix metallo proteinases (MMPs), receptor activator of nuclear factor κB ligand (RANKL), receptor activator of nuclear factor κB (RANK), osteoprotegerin (OPG), cyclooxygenase-2 (COX-2), and cathepsin K in periodontal tissue in a rat model of ligature-induced periodontitis. Male Wistar albino rats were randomly divided into 5 groups of 10 rats each: (1) nonligated, water; (2) ligated, water; (3) ligated, 1 mg/kg AZT; (4) ligated, 5 mg/kg AZT; and (5) ligated, 10 mg/kg AZT. All groups were treated with saline or AZT for 10 days. Periodontal tissues were analyzed by histopathology and immunohistochemical detection of MMP-2, MMP-9, COX-2, RANKL, RANK, OPG, and cathepsin K. Levels of IL-1β, IL-10, TNF-α, myeloperoxidase (MPO), and glutathione (GSH) were determined by ELISA. Treatment with 5 mg/kg AZT resulted in reduced MPO (p<0.05) and IL-1β (p<0.05), increased levels of IL-10 (p<0.05), and reduced expression of MMP-2, MMP-9, COX-2, RANK, RANKL, cathepsin K, and increased expression of OPG. These findings reveal that AZT increases anti-inflammatory cytokines and GSH and decreases bone loss in ligature-induced periodontitis in rats.

Rebamipide Promotes the Regeneration of Aspirin-Induced Small-Intestine Mucosal Injury through Accumulation of β-Catenin.

PubMed

Lai, Yu; Zhong, Wa; Yu, Tao; Xia, Zhong-Sheng; Li, Jie-Yao; Ouyang, Hui; Shan, Ti-Dong; Yang, Hong-Sheng; Chen, Qi-Kui

2015-01-01

The effect of rebamipide on repairing intestinal mucosal damage induced by nonsteroidal anti-inflammatory drugs and its mechanism remain unclear. In this study, we sought to explore the mechanism whereby rebamipide could promote the regeneration of aspirin-induced intestinal mucosal damage. BALB/c mice were administered aspirin (200 mg/kg/d) for 5 days to induce acute small intestinal injury (SII). Subsequently, SII mice were treated with rebamipide (320 mg/kg/d) for 5 days. The structure of intestinal barrier was observed with transmission electron microscope, and Zo-1 and occludin expressions were detected. The proliferative index was indicated by the percentage of proliferating cell nuclear antigen positive cells. The prostaglandin E2 (PGE2) levels in the small intestine tissues were measured by an enzyme immunoassay. The mRNA and protein expression levels of cyclooxygenase (COX) and β-catenin signal were detected in the small intestine using quantitative PCR and Western blot, respectively. COX expression was significantly down-regulated in aspirin induced SII (P < 0.05). In SII mice treated with rebamipide, histopathological findings of aspirin-induced intestinal inflammation were significantly milder and tight junctions between intestinal epithelial cells were improved significantly. The proliferative index increased after rebamipide treatment when compared with that in the control mice. The expressions of COX-2, β-catenin, and c-myc and the PGE2 concentrations in small intestinal tissues were significantly increased in mice with rebamipide treatments (P < 0.05). Rebamipide administration in aspirin-induced SII mice could improve the intestinal barrier structure and promote the regeneration of small intestinal epithelial injury through up-regulating COX-2 expression and the accumulation of β-catenin.

Rebamipide Promotes the Regeneration of Aspirin-Induced Small-Intestine Mucosal Injury through Accumulation of β-Catenin

PubMed Central

Yu, Tao; Xia, Zhong-Sheng; Li, Jie-Yao; Ouyang, Hui; Shan, Ti-Dong; Yang, Hong-Sheng; Chen, Qi-Kui

2015-01-01

Background The effect of rebamipide on repairing intestinal mucosal damage induced by nonsteroidal anti-inflammatory drugs and its mechanism remain unclear. In this study, we sought to explore the mechanism whereby rebamipide could promote the regeneration of aspirin-induced intestinal mucosal damage. Methods BALB/c mice were administered aspirin (200 mg/kg/d) for 5 days to induce acute small intestinal injury (SII). Subsequently, SII mice were treated with rebamipide (320 mg/kg/d) for 5 days. The structure of intestinal barrier was observed with transmission electron microscope, and Zo-1 and occludin expressions were detected. The proliferative index was indicated by the percentage of proliferating cell nuclear antigen positive cells. The prostaglandin E2 (PGE2) levels in the small intestine tissues were measured by an enzyme immunoassay. The mRNA and protein expression levels of cyclooxygenase (COX) and β-catenin signal were detected in the small intestine using quantitative PCR and Western blot, respectively. Results COX expression was significantly down-regulated in aspirin induced SII (P < 0.05). In SII mice treated with rebamipide, histopathological findings of aspirin-induced intestinal inflammation were significantly milder and tight junctions between intestinal epithelial cells were improved significantly. The proliferative index increased after rebamipide treatment when compared with that in the control mice. The expressions of COX-2, β-catenin, and c-myc and the PGE2 concentrations in small intestinal tissues were significantly increased in mice with rebamipide treatments (P < 0.05). Conclusion Rebamipide administration in aspirin-induced SII mice could improve the intestinal barrier structure and promote the regeneration of small intestinal epithelial injury through up-regulating COX-2 expression and the accumulation of β-catenin. PMID:26135128

Actinic cheilitis: epithelial expression of COX-2 and its association with mast cell tryptase and PAR-2.

PubMed

Rojas, I Gina; Martínez, Alejandra; Brethauer, Ursula; Grez, Patricia; Yefi, Roger; Luza, Sandra; Marchesani, Francisco J

2009-03-01

Cyclooxygenase-2 (COX-2) is overexpressed in various types of human malignancies, including oral cancers. Recent studies have shown that mast cell-derived protease tryptase can induce COX-2 expression by the cleavage of proteinase-activated receptor-2 (PAR-2). Actinic cheilitis (AC) is a premalignant form of lip cancer characterized by an increased density of tryptase-positive mast cells. To investigate the possible contribution of tryptase to COX-2 overexpression during early lip carcinogenesis, normal lip (n=24) and AC (n=45) biopsies were processed for COX-2, PAR-2 and tryptase detection, using RT-PCR and immunohistochemistry. Expression scores were obtained for each marker and tested for statistical significance using Mann-Whitney and Spearmann's correlation tests as well as multivariate logistic regression analysis. Increased epithelial co-expression of COX-2 and PAR-2, as well as, elevated subepithelial density of tryptase-positive mast cells were found in AC as compared to normal lip (P<0.001). COX-2 overexpression was found to be a significant predictor of AC (P<0.034, forward stepwise, Wald), and to be correlated with both tryptase-positive mast cells and PAR-2 expression (P<0.01). The results suggest that epithelial COX-2 overexpression is a key event in AC, which is associated with increased tryptase-positive mast cells and PAR-2. Therefore, tryptase may contribute to COX-2 up-regulation by epithelial PAR-2 activation during early lip carcinogenesis.

Dysregulated expression of miR-101b and miR-26b lead to age-associated increase in LPS-induced COX-2 expression in murine macrophage.

PubMed

Liu, Dan; Wang, Dongsheng; Xu, Zhenbiao; Gao, Jing; Liu, Min; Liu, Yanxin; Jiang, Minghong; Zheng, Dexian

2015-10-01

Aging is the natural process of decline in physiological structure and function of various molecules, cells, tissues, and organs. Growing evidence indicates that increased immune genetic diversity and dysfunction of immune system cause aging-related pathophysiological process with the growth of age. In the present study, we observed that LPS-induced higher activation of cyclooxygenase (COX)-2 promoter is associated with the upregulated binding activity of nuclear factor kappa B (NF-κB) in peritoneal macrophages of aged mice than young ones. Additionally, COX-2 is a direct target of miR-101b and miR-26b in the macrophages. Significant upregulation of miR-101b and miR-26b effectively prevented LPS-induced excessive expression of COX-2 in the young mice. Because these negative regulatory factors were unresponsive to LPS stimulation, the levels of COX-2 were markedly higher in the macrophages of aged mice. Further study showed that NF-κB activation contributed to the increase in the expression of miR-101b and miR-26b in the LPS-stimulated macrophages of young mice, but not aged ones. Moreover, histone deacetylase (HDAC) inhibitor trichostatin A (TSA) upregulated expression of miR-101b and miR-26b in the aged mouse macrophages only, but not the young cells. This demonstrated that HDAC suppressed the expression of miR-101b and miR-26b in the LPS-treated macrophages of aged mice and contributed to the aging process. TSA-induced increased expression of miR-101b and miR-26b could further suppress COX-2 expression. These findings provide novel evidence on the regulation of immune senescence and miR-101b and miR-26b, which might be promising targets in treating aged-related inflammatory diseases. Epigenetic regulation of the microRNAs (miRNAs) provides an important evidence for the treatment of innate inflammatory disease with HDAC inhibitors in elderly.

Mechanisms underlying the growth inhibitory effects of the cyclo-oxygenase-2 inhibitor celecoxib in human breast cancer cells

PubMed Central

Basu, Gargi D; Pathangey, Latha B; Tinder, Teresa L; Gendler, Sandra J; Mukherjee, Pinku

2005-01-01

Introduction Inhibitors of cyclo-oxygenase (COX)-2 are being extensively studied as anticancer agents. In the present study we evaluated the mechanisms by which a highly selective COX-2 inhibitor, celecoxib, affects tumor growth of two differentially invasive human breast cancer cell lines. Methods MDA-MB-231 (highly invasive) and MDA-MB-468 (moderately invasive) cell lines were treated with varying concentrations of celecoxib in vitro, and the effects of this agent on cell growth and angiogenesis were monitored by evaluating cell proliferation, apoptosis, cell cycle arrest, and vasculogenic mimicry. The in vitro results of MDA-MB-231 cell line were further confirmed in vivo in a mouse xenograft model. Results The highly invasive MDA-MB-231 cells express higher levels of COX-2 than do the less invasive MDA-MB-468 cells. Celecoxib treatment inhibited COX-2 activity, indicated by prostaglandin E2 secretion, and caused significant growth arrest in both breast cancer cell lines. In the highly invasive MDA-MB-231 cells, the mechanism of celecoxib-induced growth arrest was by induction of apoptosis, associated with reduced activation of protein kinase B/Akt, and subsequent activation of caspases 3 and 7. In the less invasive MDA-MB-468 cells, growth arrest was a consequence of cell cycle arrest at the G0/G1 checkpoint. Celecoxib-induced growth inhibition was reversed by addition of exogenous prostaglandin E2 in MDA-MB-468 cells but not in MDA-MB-231 cells. Furthermore, MDA-MB-468 cells formed significantly fewer extracellular matrix associated microvascular channels in vitro than did the high COX-2 expressing MDA-MB-231 cells. Celecoxib treatment not only inhibited cell growth and vascular channel formation but also reduced vascular endothelial growth factor levels. The in vitro findings corroborated in vivo data from a mouse xenograft model in which daily administration of celecoxib significantly reduced tumor growth of MDA-MB-231 cells, which was associated with reduced vascularization and increased necrosis in the tumor mass. Conclusion The disparate molecular mechanisms of celecoxib-induced growth inhibition in human breast cancer cells depends upon the level of COX-2 expression and the invasive potential of the cell lines examined. Data suggest a role for COX-2 not only in the growth of cancer cells but also in activating the angiogenic pathway through regulating levels of vascular endothelial growth factor. PMID:15987447

Targeted Deletions of COX-2 and Atherogenesis in Mice

PubMed Central

Hui, Yiqun; Ricciotti, Emanuela; Crichton, Irene; Yu, Zhou; Wang, Dairong; Stubbe, Jane; Wang, Miao; Puré, Ellen; FitzGerald, Garret A.

2010-01-01

Background While the dominant product of vascular cyclooxygenase (COX)-2, prostacyclin (PGI2), restrains atherogenesis, inhibition and deletion of COX-2 have yielded conflicting results in mouse models of atherosclerosis. Floxed mice were used to parse distinct cellular contributions of COX-2 in macrophages (Mac) and T cells (TC) to atherogenesis. Methods and Results Deletion of Mac COX-2 (MacKO) was attained using LysMCre mice and suppressed completely lipopolysaccharide (LPS) stimulated Mac prostaglandin (PG) formation and LPS evoked systemic PG biosynthesis by ∼ 30%. LPS stimulated COX-2 expression was suppressed in polymorphonuclear leucocytes (PMN) isolated from MacKOs, but PG formation was not even detected in PMN supernatants from control mice. Atherogenesis was attenuated when MacKOs were crossed into hyperlipidemic LdlR KOs. Deletion of Mac COX-2 appeared to remove a restraint on COX-2 expression in lesional non-leukocyte (CD45 and CD11b negative) vascular cells that express vascular cell adhesion molecule and variably, α-smooth muscle actin and vimentin, portending a shift in PG profile and consequent atheroprotection. Basal expression of COX-2 was minimal in TCs, but use of CD4Cre to generate TC knockouts (TCKOs) depressed its modest upregulation by anti-CD3ε. However, biosynthesis of PGs, TC composition in lymphatic organs and atherogenesis in LDLR KOs were unaltered in TCKOs. Conclusions Mac COX-2, primarily a source of thromboxane A2 and PGE2, promotes atherogenesis and exerts a restraint on enzyme expression by lesional cells suggestive of vascular smooth muscle cells, a prominent source of atheroprotective PGI2. TC COX-2 does not influence detectably TC development or function nor atherogenesis in mice. PMID:20530000

Targeted Deletion and Lipidomic Analysis Identify Epithelial Cell COX-2 as a Major Driver of Chemically-induced Skin Cancer

PubMed Central

Jiao, Jing; Ishikawa, Tomo-o; Dumlao, Darren S.; Norris, Paul C.; Magyar, Clara E.; Mikulec, Carol; Catapang, Art; Dennis, Edward A.; Fischer, Susan M.; Herschman, Harvey R.

2014-01-01

Pharmacologic and global gene deletion studies demonstrate that cyclooxygenase-2 (PTGS2/COX2) plays a critical role in DMBA/TPA-induced skin tumor induction. While many cell types in the tumor microenvironment express COX-2, the cell types in which COX-2 expression is required for tumor promotion are not clearly established. Here, cell-type specific Cox-2 gene deletion reveals a vital role for skin epithelial cell COX-2 expression in DMBA/TPA tumor induction. In contrast, myeloid Cox-2 gene deletion has no effect on DMBA/TPA tumorigenesis. The infrequent, small tumors that develop on mice with an epithelial cell-specific Cox-2 gene deletion have decreased proliferation and increased cell differentiation properties. Blood vessel density is reduced in tumors with an epithelial cell-specific Cox-2 gene deletion, compared to littermate control tumors, suggesting a reciprocal relationship in tumor progression between COX-2 expressing tumor epithelial cells and microenvironment endothelial cells. Lipidomics analysis of skin and tumors from DMBA/TPA-treated mice suggests that the prostaglandins PGE2 and PGF2α are likely candidates for the epithelial cell COX-2-dependent eicosanoids that mediate tumor progression. This study both illustrates the value of cell-type specific gene deletions in understanding the cellular roles of signal-generating pathways in complex microenvironments and emphasizes the benefit of a systems-based lipidomic analysis approach to identify candidate lipid mediators of biological responses. PMID:25063587

Misoprostol Reverse Hippocampal Neuron Cyclooxygenase-2 Downstream Signaling Imbalance in Aluminum-Overload Rats

PubMed Central

Guo, Yuanxin; Lei, Wenjuan; Wang, Jianfeng; Hu, Xinyue; Wei, Yuling; Ji, Chaonan; Yang, Junqing

2016-01-01

Although COX-2 inhibition in animal models of neurodegenerative diseases has shown neuroprotection, recent studies have revealed some serious side effects (ulcers, bleeding, fatal cerebrovascular diseases etc.) and the limited benefits of COX-2 inhibitors. A more focused approach is necessary to explore the therapeutic effect of the COX downstream signaling pathway in neurological research. The aim of this study was to explore the alterations of the PGES-PGE2-EP signal pathway and the effect of misoprostol on neurodegeneration by chronic aluminum-overload in rats. Adult rats were treated by intragastric administration of aluminum gluconate. The PGE2 content and expression of PGES and EPs in the hippocampi of rats were detected using ELISA, q-PCR and Western blot analysis, respectively. The content of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) in the rat hippocampi were also detected. The misoprostol treatment dose-dependently improved spatial learning and memory function as well as healing after hippocampal neuron damage induced by chronic aluminum-overload in rats. Meanwhile, the administration of misoprostol resulted in a decrease in the PGE2 level and down-regulation of the mPGES-1, EP2 and EP4 expression levels, while there was a dose-dependent up-regulation of EP3 expression. These results suggest that misoprostol possesses a neuroprotective property, and the mechanism involves affecting the EP3 level and reducing the endogenous production of PGE2 through a negative feedback mechanism, increasing the EP3 expression level, decreasing the EP2 and EP4 expression levels, and rebuilding the mPGES-1-PGE2-EP1-4 signal pathway balance. In this way, misoprostol has a counteractive effect on oxidant stress and inflammation in the central nervous system. The PGES-PGE2-EPs signaling pathway is a potential therapeutic strategy for treating neurodegeneration in patients. PMID:27033056

Apoptosis Inducing Effect of Plumbagin on Colonic Cancer Cells Depends on Expression of COX-2

PubMed Central

Subramaniya, Bharathi Raja; Srinivasan, Gayathri; Mohammed Sadullah, Sakeena Sadullah; Davis, Nimitha; Baddi Reddi Subhadara, Lakshmi; Halagowder, Devaraj; Sivasitambaram, Niranjali Devaraj

2011-01-01

Plumbagin, a quinonoid found in the plants of the Plumbaginaceae, possesses medicinal properties. In this study we investigated the anti-proliferative and apoptotic activity of plumbagin by using two human colonic cancer cell lines, HT29 and HCT15. IC50 of Plumbagin for HCT15 and HT29 cells (22.5 µM and 62.5 µM, respectively) were significantly different. To study the response of cancer cells during treatment strategies, cells were treated with two different concentrations, 15 µM, 30 µM for HCT15 and 50 µM, 75 µM for HT29 cells. Though activation of NFκB, Caspases-3, elevated levels of TNF-α, cytosolic Cytochrome C were seen in both HCT15 cells HT29 treated with plumbagin, aberrant apoptosis with decreased level of pEGFR, pAkt, pGsk-3β, PCNA and Cyclin D1was observed only in 15 µM and 30 µM plumbagin treated HCT15 and 75 µM plumbagin treated HT29 cells. This suggests that plumbagin induces apoptosis in both HCT15 cells and HT29 treated, whereas, proliferation was inhibited only in 15 µM and 30 µM plumbagin treated HCT15 and 75 µM plumbagin treated HT29 cells, but not in 50 µM plumbagin treated HT29 cells. Expression of COX-2 was decreased in 75 µM plumbagin treated HT29 cells when compared to 50 µM plumbagin treated HT29 cells, whereas HCT15 cells lack COX. Hence the observed resistance to induction of apoptosis in 50 µM plumbagin treated HT29 cells are attributed to the expression of COX-2. In conclusion, plumbagin induces apoptosis in colonic cancer cells through TNF-α mediated pathway depending on expression of COX-2 expression. PMID:21559086

Houttuynia cordata, a novel and selective COX-2 inhibitor with anti-inflammatory activity.

PubMed

Li, Weifeng; Zhou, Ping; Zhang, Yanmin; He, Langchong

2011-01-27

Houttuynia cordata Thunb. (Saururaceae; HC) has been long used in traditional oriental medicine for the treatment of inflammation diseases. Modern research has implicated inducible cyclooxygenase-2 (COX-2) as a key regulator of the inflammatory process. In the present study, we aimed to investigate the effect of HC on COX-2. We examined the effects of HC on lipopolysaccharide (LPS)-induced prostaglandin (PG) E(2) production, an indirect indicator of COX-2 activity, and COX-2 gene and protein expression in mouse peritoneal macrophages. LPS-induced mouse peritoneal macrophages were employed as an in vitro model system. LPS-induced PGE(2) production was assessed by enzyme-linked immunosorbant assay and COX-2 protein expression was assessed by Western blot assay. The results showed that HC was able to inhibit the release of LPS-induced PGE(2) from mouse peritoneal macrophages (IC50 value: 44.8 μg/mL). Moreover, the inhibitory activity of HC essential oil elicited a dose-dependent inhibition of COX-2 enzyme activity (IC50 value: 30.9 μg/mL). HC was also found to cause reduction in LPS-induced COX-2 mRNA and protein expression, but did not affect COX-1 expression. The non-steroidal anti-inflammatory drug (NSAID) and specific COX-2 inhibitor NS398 functioned similarly in LPS-induced mouse peritoneal macrophages. Taken together, our data suggest HC mediates inhibition of COX-2 enzyme activity and can affect related gene and protein expression. HC works by a mechanism of action similar to that of NSAIDs. These results add a novel aspect to the biological profile of HC. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Chronic Arsenic Exposure and Angiogenesis in Human Bronchial Epithelial Cells via the ROS/miR-199a-5p/HIF-1α/COX-2 Pathway

PubMed Central

He, Jun; Wang, Min; Jiang, Yue; Chen, Qiudan; Xu, Shaohua; Xu, Qing; Jiang, Bing-Hua

2014-01-01

Background: Environmental and occupational exposure to arsenic is a major public health concern. Although it has been identified as a human carcinogen, the molecular mechanism underlying the arsenic-induced carcinogenesis is not well understood. Objectives: We aimed to determine the role and mechanisms of miRNAs in arsenic-induced tumor angiogenesis and tumor growth. Methods: We utilized an in vitro model in which human lung epithelial BEAS-2B cells were transformed through long-term exposure to arsenic. A human xenograft tumor model was established to assess tumor angiogenesis and tumor growth in vivo. Tube formation assay and chorioallantoic membranes assay were used to assess tumor angiogenesis. Results: We found that miR-199a-5p expression levels were more than 100-fold lower in arsenic-transformed cells than parental cells. Re-expression of miR-199a-5p impaired arsenic-induced angiogenesis and tumor growth through its direct targets HIF-1α and COX-2. We further showed that arsenic induced COX-2 expression through HIF-1 regulation at the transcriptional level. In addition, we demonstrated that reactive oxygen species are an upstream event of miR-199a-5p/ HIF-1α/COX-2 pathway in arsenic-induced carcinogenesis. Conclusion: The findings establish critical roles of miR-199a-5p and its downstream targets HIF-1/COX-2 in arsenic-induced tumor growth and angiogenesis. Citation: He J, Wang M, Jiang Y, Chen Q, Xu S, Xu Q, Jiang BH, Liu LZ. 2014. Chronic arsenic exposure and angiogenesis in human bronchial epithelial cells via the ROS/miR-199a-5p/HIF-1α/COX-2 Pathway. Environ Health Perspect 122:255–261; http://dx.doi.org/10.1289/ehp.1307545 PMID:24413338

Electroacupuncture attenuates mechanical allodynia by suppressing the spinal JNK1/2 pathway in a rat model of inflammatory pain.

PubMed

Du, Jun-Ying; Fang, Jian-Qiao; Liang, Yi; Fang, Jun-Fan

2014-09-01

Electroacupuncture (EA) has a substantial analgesic effect on inflammatory pain induced by complete Freund's adjuvant (CFA). The activation of the c-Jun N-terminal kinase 1/2 (JNK1/2) signal transduction pathway in the spinal cord is associated with inflammatory pain. However, the relationship between EA's analgesic effect and the JNK1/2 signal transduction pathway in the inflammatory pain remain unclear. In the present study, we used the established rat model of CFA-induced inflammatory pain to investigate the role of the spinal JNK1/2 pathway in EA-mediated analgesia. We observed a decrease in paw withdrawal thresholds and an increase in paw edema at 1 and 3 days after injecting CFA into the right hindpaw. CFA, 3 days after injection, upregulated expression of phospho-c-Jun N-terminal kinase1/2 (p-JNK1/2) protein and its downstream targets, the transcriptional regulators p-c-Jun and activator protein-1 (AP-1), as well as cyclooxygenase-2 (COX-2) and the transient receptor potential vanilloid 1 (TRPV1). EA significantly alleviated CFA-induced inflammatory pain. In addition, EA reduced p-JNK1/2 protein levels and COX-2 mRNA expressions, a degree of down-regulated p-c-Jun protein level and AP-1 DNA binding activity in the spinal dorsal horn of CFA-administered animals, but it had no effect on TRPV1 mRNA expression. Furthermore, EA and the JNK inhibitor SP600125 synergistically inhibited CFA-induced hyperalgesia and suppressed the COX-2 mRNA expression in the spinal dorsal horn. Our findings indicate that EA alleviates inflammatory pain behavior, at least in part, by reducing COX-2 expression in the spinal cord via the JNK1/2 signaling pathway. Inactivation of the spinal JNK1/2 signal transduction pathway maybe the potential mechanism of EA's antinociception in the inflammatory pain model. Copyright © 2014 Elsevier Inc. All rights reserved.

Selective inhibition of inducible cyclooxygenase 2 in vivo is antiinflammatory and nonulcerogenic.

PubMed Central

Masferrer, J L; Zweifel, B S; Manning, P T; Hauser, S D; Leahy, K M; Smith, W G; Isakson, P C; Seibert, K

1994-01-01

We have examined the role of cyclooxygenase 2 (COX-2) in a model of inflammation in vivo. Carrageenan administration to the subcutaneous rat air pouch induces a rapid inflammatory response characterized by high levels of prostaglandins (PGs) and leukotrienes in the fluid exudate. The time course of the induction of COX-2 mRNA and protein coincided with the production of PGs in the pouch tissue and cellular infiltrate. Carrageenan-induced COX-2 immunoreactivity was localized to macrophages obtained from the fluid exudate as well as to the inner surface layer of cells within the pouch lining. Dexamethasone inhibited both COX-2 expression and PG synthesis in the fluid exudate but failed to inhibit PG synthesis in the stomach. Furthermore, NS-398, a selective COX-2 inhibitor, and indomethacin, a nonselective COX-1/COX-2 inhibitor, blocked proinflammatory PG synthesis in the air pouch. In contrast, only indomethacin blocked gastric PG and, additionally, produced gastric lesions. These results suggest that inhibitors of COX-2 are potent antiinflammatory agents which do not produce the typical side effects (e.g., gastric ulcers) associated with the nonselective, COX-1-directed antiinflammatory drugs. Images PMID:8159730

Mast cells exert pro-inflammatory effects of relevance to the pathophyisology of tendinopathy.

PubMed

Behzad, Hayedeh; Sharma, Aishwariya; Mousavizadeh, Rouhollah; Lu, Alex; Scott, Alex

2013-01-01

We have previously found an increased mast cell density in tendon biopsies from patients with patellar tendinopathy compared to controls. This study examined the influence of mast cells on basic tenocyte functions, including production of the inflammatory mediator prostaglandin E2 (PGE2), extracellular matrix remodeling and matrix metalloproteinase (MMP) gene transcription, and collagen synthesis. Primary human tenocytes were stimulated with an established human mast cell line (HMC-1). Extracellular matrix remodeling was studied by culturing tenocytes in a three-dimensional collagen lattice. Survival/proliferation was assessed with the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium salt (MTS) assay. Levels of mRNA for COX-2, COL1A1, MMP1, and MMP7 were determined by quantitative real-time polymerase chain reaction (qPCR). Cox-2 protein level was assessed by Western blot analysis and type I procollagen was detected by immunofluorescent staining. PGE2 levels were determined using an enzyme-linked immunosorbent assay (ELISA). Mast cells stimulated tenocytes to produce increased levels of COX-2 and the pro-inflammatory mediator PGE2, which in turn decreased COL1A1 mRNA expression. Additionally, mast cells reduced the type I procollagen protein levels produced by tenocytes. Transforming growth factor beta 1 (TGF-β1) was responsible for the induction of Cox-2 and PGE2 by tenocytes. Mast cells increased MMP1 and MMP7 transcription and increased the contraction of a three-dimensional collagen lattice by tenocytes, a phenomenon which was blocked by a pan-MMP inhibitor (Batimastat). Our data demonstrate that mast cell-derived PGE2 reduces collagen synthesis and enhances expression and activities of MMPs in human tenocytes.

Correlation between expression of cyclooxygenase-2 and angiogenesis in human gastric adenocarcinoma

PubMed Central

Li, Hong-Xia; Chang, Xin-Ming; Song, Zheng-Jun; He, Shui-Xiang

2003-01-01

AIM: To evaluate the expression of cyclooxygenase (COX-2) and the relationship with tumor angiogenesis and advancement in gastric adenocarcinoma. METHODS: Immunohistochemical stain was used for detecting the expression of COX-2 in 45 resected specimens of gastric adenocarcinoma; the monoclonal antibody against CD34 was used for displaying vascular endothelial cells, and microvascular density (MVD) was detected by counting of CD34-positive vascular endothelial cells. Paracancerous tissues were examined as control. RESULTS: Immunohistological staining with COX-2-specific polyclonal antibody showed cytoplasmic staining in the cancer cells, some atypical hyperplasia and intestinal metaplasia, as well as angiogenic vasculature present within the tumors and prexisting vasculature adjacent to cancer lesions. The rate of expression of COX-2 and MVD index in gastric cancers were significantly increased, compared with those in the paracancerous tissues (77.78 vs 33.33%, 58.13 ± 19.99 vs 24.02 ± 10.28, P < 0.01, P < 0.05, respectively). In 36 gastric carcinoma specimens with lymph node metastasis, the rate of COX-2 expression and MVD were higher than those in the specimens without metostasis (86.11 vs 44.44%, 58.60 ± 18.24 vs 43.54 ± 15.05, P < 0.05, P < 0.05, respectively). The rate of COX-2 expression and MVD in the specimens with invasive serosa were significantly higher than those in the specimens without invasion to serosa (87.88 vs 50.0%, 57.01 ± 18.79 vs 42.35 ± 14.65, P < 0.05, P < 0.05). Moreover, MVD in COX-2-positive specimens was higher than that in COX-2-negative specimens (61.29 ± 14.31 vs 45.38 ± 12.42, P < 0.05). COX-2 expression was positively correlated with MVD (r = 0.63, P < 0.05). CONCLUSION: COX-2 expression might correlate with the occurance and advancement of gastric carcinoma and is involved in tumor angiogenesis in gastric carcinoma. It is likely that COX-2 by inducing angiogenesis can be one of mechanisms which promotes invasion and metastasis of gastric carcinoma. It may become a new therapeutic target for anti-angiogenesis. PMID:12679908

Epidermal Growth Factor and Interleukin-1β Utilize Divergent Signaling Pathways to Synergistically Upregulate Cyclooxygenase-2 Gene Expression in Human Amnion-Derived WISH Cells1

PubMed Central

Ackerman, William E.; Rovin, Brad H.; Kniss, Douglas A.

2006-01-01

In human parturition, uterotonic prostaglandins (PGs) arise predominantly via increased expression of cyclooxygenase-2 (COX-2 [also known as prostaglandin synthase 2]) within intra-uterine tissues. Interleukin-1 (IL-1) and epidermal growth factor (EGF), both inducers of COX-2 transcription, are among numerous factors that accumulate within amniotic fluid with advancing gestation. It was previously demonstrated that EGF could potentiate IL-1β-driven PGE2 production in amnion and amnion-derived (WISH) cells. To define the mechanism for this observation, we hypothesized that EGF and IL-1β might exhibit synergism in regulating COX-2 gene expression. In WISH cells, combined treatment with EGF and IL-1β resulted in a greater-than-additive increase in COX-2 mRNA relative to challenge with either agent independently. Augmentation of IL-1β-induced transactivation by EGF was not observed in cells harboring reporter plasmids bearing nuclear factor-kappa B (NFκB) regulatory elements alone, but was evident when a fragment (−891/+9) of the COX-2 gene 5′-promoter was present. Both agents transiently activated intermediates of multiple signaling pathways potentially involved in the regulation of COX-2 gene expression. The 26 S proteasome inhibitor, MG-132, selectively abrogated IL-1β-driven NFκB activation and COX-2 mRNA expression. Only pharmacologic blockade of the p38 mitogen-activated protein kinase eliminated COX-2 expression following EGF stimulation. We conclude that EGF and IL-1β appear to signal through different signaling cascades leading to COX-2 gene expression. IL-1β employs the NFκB pathway predominantly, while the spectrum of EGF signaling is broader and includes p38 kinase. The synergism observed between IL-1β and EGF does not rely on augmented NFκB function, but rather, occurs through differential use of independent response elements within the COX-2 promoter. PMID:15329330

Breast cancer cell cyclooxygenase-2 expression alters extracellular matrix structure and function and numbers of cancer associated fibroblasts.

PubMed

Krishnamachary, Balaji; Stasinopoulos, Ioannis; Kakkad, Samata; Penet, Marie-France; Jacob, Desmond; Wildes, Flonne; Mironchik, Yelena; Pathak, Arvind P; Solaiyappan, Meiyappan; Bhujwalla, Zaver M

2017-03-14

Cyclooxygenase-2 (COX-2) is a critically important mediator of inflammation that significantly influences tumor angiogenesis, invasion, and metastasis. We investigated the role of COX-2 expressed by triple negative breast cancer cells in altering the structure and function of the extracellular matrix (ECM). COX-2 downregulation effects on ECM structure and function were investigated using magnetic resonance imaging (MRI) and second harmonic generation (SHG) microscopy of tumors derived from triple negative MDA-MB-231 breast cancer cells, and a derived clone stably expressing a short hairpin (shRNA) molecule downregulating COX-2. MRI of albumin-GdDTPA was used to characterize macromolecular fluid transport in vivo and SHG microscopy was used to quantify collagen 1 (Col1) fiber morphology. COX-2 downregulation decreased Col1 fiber density and altered macromolecular fluid transport. Immunohistochemistry identified significantly fewer activated cancer associated fibroblasts (CAFs) in low COX-2 expressing tumors. Metastatic lung nodules established by COX-2 downregulated cells were infrequent, smaller, and contained fewer Col1 fibers.COX-2 overexpression studies were performed with tumors derived from triple negative SUM-149 breast cancer cells lentivirally transduced to overexpress COX-2. SHG microscopy identified significantly higher Col1 fiber density in COX-2 overexpressing tumors with an increase of CAFs. These data expand upon the roles of COX-2 in shaping the structure and function of the ECM in primary and metastatic tumors, and identify the potential role of COX-2 in modifying the number of CAFs in tumors that may have contributed to the altered ECM.

Effects of low-level laser therapy (LLLT) and diclofenac (topical and intramuscular) as single and combined therapy in experimental model of controlled muscle strain in rats.

PubMed

de Paiva Carvalho, Rodrigo Leal; Leal-Junior, Ernesto Cesar Pinto; Petrellis, Maria Carla; Marcos, Rodrigo Labat; de Carvalho, Maria Helena Catelli; De Nucci, Gilberto; Lopes-Martins, Rodrigo Alvaro Brandão

2013-01-01

Muscle injuries represent ca 30% of sports injuries and excessive stretching of muscle causes more than 90% of injuries. Currently the most used treatments are nonsteroidal anti-inflammatory drugs (NSAIDs), however, in last years, low-level laser therapy (LLLT) is becoming an interesting therapeutic modality. The aim of this study was to evaluate the effect of single and combined therapies (LLLT, topical application of diclofenac and intramuscular diclofenac) on functional and biochemical aspects in an experimental model of controlled muscle strain in rats. Muscle strain was induced by overloading tibialis anterior muscle of rats. Injured groups received either no treatment, or a single treatment with topical or intramuscular diclofenac (TD and ID), or LLLT (3 J, 810 nm, 100 mW) 1 h after injury. Walking track analysis was the functional outcome and biochemical analyses included mRNA expression of COX-1 and COX-2 and blood levels of prostaglandin E2 (PGE2 ). All treatments significantly decreased COX-1 and COX-2 gene expression compared with injury group (P < 0.05). However, LLLT showed better effects than TD and ID regarding PGE2 levels and walking track analysis (P < 0.05). We can conclude that LLLT has more efficacy than topical and intramuscular diclofenac in treatment of muscle strain injury in acute stage. © 2012 Wiley Periodicals, Inc. Photochemistry and Photobiology © 2012 The American Society of Photobiology.

Exisulind in combination with celecoxib modulates epidermal growth factor receptor, cyclooxygenase-2, and cyclin D1 against prostate carcinogenesis: in vivo evidence.

PubMed

Narayanan, Bhagavathi A; Reddy, Bandaru S; Bosland, Maarten C; Nargi, Dominick; Horton, Lori; Randolph, Carla; Narayanan, Narayanan K

2007-10-01

Nonsteroidal anti-inflammatory drugs mediate anticancer effects by modulating cyclooxygenase-2 (COX-2)-dependent and/or COX-2-independent mechanism(s); however, the toxicity issue is a concern with single agents at higher doses. In this study, we determined the combined effect of celecoxib, a COX-2 inhibitor, along with exisulind (sulindac sulfone/Aptosyn) at low doses in prostate cancer. We used a sequential regimen of N-methyl-N-nitrosourea + testosterone to induce prostate cancer in Wistar-Unilever rats. Following carcinogen treatment, celecoxib and exisulind individually and their combination at low doses were given in NIH-07 diet for 52 weeks. We determined the incidence of prostatic intraepithelial neoplasia, adenocarcinomas, rate of tumor cell proliferation, and apoptosis. Immunohistochemical and Western blot analysis were done to determine COX-2, epidermal growth factor receptor (EGFR), Akt, androgen receptor, and cyclin D1 expression. Serum prostaglandin E2 and tumor necrosis factor-alpha levels were determined using enzyme immunoassay/ELISA assays. The rats that received celecoxib in combination with exisulind at low doses showed a significant decrease in prostatic intraepithelial neoplasia and adenocarcinomas as well as an enhanced rate of apoptosis. An overall decrease in COX-2, EGFR, Akt, androgen receptor, and cyclin D1 expression was found associated with tumor growth inhibition. Reduced serum levels of COX-2 protein, prostaglandin E2, and tumor necrosis factor-alpha indicated anti-inflammatory effects. A strong inhibition of total and phosphorylated form of EGFR (Tyr(992) and Tyr(845)) and Akt (Ser(473)) was significant in rats given with these agents in combination. In this study, we show for the first time that the combination of celecoxib with exisulind at low doses could prevent prostate carcinogenesis by altering key molecular events.

Differential regulation of collagen secretion by kinin receptors in cardiac fibroblast and myofibroblast

DOE Office of Scientific and Technical Information (OSTI.GOV)

Catalán, Mabel; Smolic, Christian; Contreras, Ariel

Kinins mediate their cellular effects through B1 (B1R) and B2 (B2R) receptors, and the activation of B2R reduces collagen synthesis in cardiac fibroblasts (CF). However, the question of whether B1R and/or B2R have a role in cardiac myofibroblasts remains unanswered. Methods: CF were isolated from neonate rats and myofibroblasts were generated by an 84 h treatment with TGF-β1 (CMF). B1R was evaluated by western blot, immunocytochemistry and radioligand assay; B2R, inducible nitric oxide synthase (iNOS), endothelial nitric oxide synthase (eNOS), and cyclooxygenases 1and 2 (COX-1, and COX-2) were evaluated by western blot; intracellular Ca{sup +2} levels were evaluated with Fluo-4AM;more » collagen secretion was measured in the culture media using the picrosirius red assay kit. Results: B2R, iNOS, COX-1 and low levels of B1R but not eNOS, were detected by western blot in CF. Also, B1R, B2R, and COX-2 but not iNOS, eNOS or COX-1, were detected by western blot in CMF. By immunocytochemistry, our results showed lower intracellular B1R levels in CF and higher B1R levels in CMF, mainly localized on the cell membrane. Additionally, we found B1R only in CMF cellular membrane through radioligand displacement assay. Bradykinin (BK) B2R agonist increased intracellular Ca{sup 2+} levels and reduced collagen secretion both in CF and CMF. These effects were blocked by HOE-140, and inhibited by L-NAME, 1400W and indomethacin. Des-Arg-kallidin (DAKD) B1R agonist did not increase intracellular Ca{sup 2+} levels in CF; however, after preincubation for 1 h with DAKD and re-stimulation with the same agonist, we found a low increase in intracellular Ca{sup 2+} levels. Finally, DAKD increased intracellular Ca{sup 2+} levels and decreased collagen secretion in CMF, being this effect blocked by the B1R antagonist des-Arg9-Leu8-kallidin and indomethacin, but not by L-NAME or 1400 W. Conclusion: B1R, B2R, iNOS and COX-1 were expressed differently between CF and CMF, and collagen secretion was regulated differentially by kinin receptor agonists in cultured CF and CMF. -- Highlights: ► B1 and B2 kinin receptors modulates collagen secretion in cardiac myofibroblast. ► TGF-β1 increases B1 kinin receptor expression levels in cardiac myofibroblast. ► B1 kinin receptor through COX-2 decreases collagen synthesis in cardiac myofibroblast.« less

Celecoxib Ameliorates Non-Alcoholic Steatohepatitis in Type 2 Diabetic Rats via Suppression of the Non-Canonical Wnt Signaling Pathway Expression

PubMed Central

Tian, Feng; Zhang, Ya Jie; Li, Yu; Xie, Ying

2014-01-01

Our aim was to test whether pharmacological inhibition of cycloxygenase-2 (COX-2) reverses non-alcoholic steatohepatitis (NASH) in type 2 diabetes mellitus (T2DM) rats via suppression of the non-canonical Wnt signaling pathway expression. Twenty-four male Sprague-Dawley rats were randomly distributed to two groups and were fed with a high fat and sucrose (HF-HS) diet or a normal chow diet, respectively. After four weeks, rats fed with a HF-HS diet were made diabetic with low-dose streptozotocin. At the 9th week the diabetic rats fed with a HF-HS diet or the non-diabetic rats fed with a normal chow diet were further divided into two subgroups treated with vehicle or celecoxib (a selective COX-2 inhibitor, 10 mg/Kg/day, gavage) for the last 4 weeks, respectively. At the end of the 12th week, rats were anesthetized. NASH was assessed by histology. Related cytokine expression was measured at both the protein and gene levels through immunohistochemistry (IHC), Western blot and real-time PCR. T2DM rats fed with a HF-HS diet developed steatohepatitis and insulin resistance associated with elevated serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), insulin levels and the non-alcoholic fatty liver disease (NAFLD) activity score (NAS). The expression of Wnt5a, JNK1, NF-κB p65, and COX-2 were all significantly increased in the T2DM-NASH group compared with the control and control-cele group. Hepatic injury was improved by celecoxib in T2DM-NASH-Cele group indicated by reduced serum ALT and AST levels and hepatic inflammation was reduced by celecoxib showed by histology and the NAFLD activity score (NAS). Serum related metabolic parameters, HOMA-IR and insulin sensitivity index were all improved by celecoxib. The expression of Wnt5a, JNK1, NF-κB p65, and COX-2 expression were all suppressed by celecoxib in T2DM-NASH-Cele group. The results of the present study indicated that celecoxib ameliorated NASH in T2DM rats via suppression of the non-canonical Wnt5a/JNK1 signaling pathway expression. PMID:24404139

Anti-inflammatory Activity of Grains of Paradise (Aframomum melegueta Schum) Extract

PubMed Central

2015-01-01

The ethanolic extract of grains of paradise (Aframomum melegueta Schum, Zingiberaceae) has been evaluated for inhibitory activity on cyclooxygenase-2 (COX-2) enzyme, in vivo for the anti-inflammatory activity and expression of several pro-inflammatory genes. Bioactivity-guided fractionation showed that the most active COX-2 inhibitory compound in the extract was [6]-paradol. [6]-Shogaol, another compound from the extract, was the most active inhibitory compound in pro-inflammatory gene expression assays. In a rat paw edema model, the whole extract reduced inflammation by 49% at 1000 mg/kg. Major gingerols from the extract [6]-paradol, [6]-gingerol, and [6]-shogaol reduced inflammation by 20, 25 and 38%. respectively when administered individually at a dose of 150 mg/kg. [6]-Shogaol efficacy was at the level of aspirin, used as a positive control. Grains of paradise extract has demonstrated an anti-inflammatory activity, which is in part due to the inhibition of COX-2 enzyme activity and expression of pro-inflammatory genes. PMID:25293633

A dual inhibitor of cyclooxygenase and 5-lipoxygenase protects against kainic acid-induced brain injury.

PubMed

Minutoli, Letteria; Marini, Herbert; Rinaldi, Mariagrazia; Bitto, Alessandra; Irrera, Natasha; Pizzino, Gabriele; Pallio, Giovanni; Calò, Margherita; Adamo, Elena Bianca; Trichilo, Vincenzo; Interdonato, Monica; Galfo, Federica; Squadrito, Francesco; Altavilla, Domenica

2015-06-01

Systemic administration of kainic acid causes inflammation and apoptosis in the brain, resulting in neuronal loss. Dual cyclooxygenase/5-lipoxygenase (COX/5-LOX) inhibitors could represent a possible neuroprotective approach in preventing glutamate excitotoxicity. Consequently, we investigated the effects of a dual inhibitor of COX/5-LOX following intraperitoneal administration of kainic acid (KA, 10 mg/kg) in rats. Animals were randomized to receive either the dual inhibitor of COX/5-LOX (flavocoxid, 20 mg/kg i.p.) or its vehicle (1 ml/kg i.p.) 30 min after KA administration. Sham brain injury rats were used as controls. We evaluated protein expression of phosphorylated extracellular signal-regulated kinase (p-ERK1/2) and tumor necrosis factor alpha (TNF-α) as well as levels of malondialdehyde (MDA), prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) in the hippocampus. Animals were also observed for monitoring behavioral changes according to Racine Scale. Finally, histological analysis and brain edema evaluation were carried out. Treatment with the dual inhibitor of COX/5-LOX decreased protein expression of p-ERK1/2 and TNF-α in hippocampus, markedly reduced MDA, LTB4 and PGE2 hippocampal levels, and also ameliorated brain edema. Histological analysis showed a reduction in cell damage in rats treated with the dual inhibitor of COX/5-LOX, particularly in hippocampal subregion CA3c. Moreover, flavocoxid significantly improved behavioral signs following kainic acid administration. Our results suggest that dual inhibition of COX/5-LOX by flavocoxid has neuroprotective effects during kainic acid-induced excitotoxicity.

COX-2 expression in canine anal sac adenocarcinomas and in non-neoplastic canine anal sacs.

PubMed

Knudsen, C S; Williams, A; Brearley, M J; Demetriou, J L

2013-09-01

Anal sac adenocarcinoma (ASAC) is a clinically significant canine neoplasm characterized by early lymphatic invasion. Up-regulation of cyclooxygenase isoform 2 (COX-2) has been confirmed in several animal and human neoplastic tissues. The aim of the current study was primarily to evaluate COX-2 expression in canine ASAC and compare it to COX-2 expression in non-neoplastic canine anal sac tissue using immunohistochemistry with scoring for percentage positivity and intensity. Twenty-five ASAC samples and 22 normal anal sacs were available for evaluation. All canine ASAC samples and the normal anal sac tissues stained positively for COX-2. However, while normal anal sac tissue showed strong staining of the ductal epithelial cells, ASAC samples showed staining of the neoplastic glandular epithelial cells, with varying percentage positivity and intensity between ASAC samples. COX-2 immunoreactivity of ASAC samples was of low intensity in 52% and high in 12% of the cases; the remaining samples were of intermediate intensity. Seventy-six per cent of the ASAC had over 50% of the neoplastic glandular cells staining positive. These results confirm that COX-2 is expressed in the neoplastic glandular epithelial cells in canine ASAC and suggest a potential role for COX-2 inhibitors in the management of ASAC. Furthermore, the results indicate that COX-2 is expressed in ductal epithelial cells of the normal anal sac. Copyright © 2013 Elsevier Ltd. All rights reserved.

Early increased density of cyclooxygenase-2 (COX-2) immunoreactive neurons in Down syndrome.

PubMed

Mulet, Maria; Blasco-Ibáńez, José Miguel; Crespo, Carlos; Nácher, Juan; Varea, Emilio

2017-01-01

Neuroinflammation is one of the hallmarks of Alzheimer's disease. One of the enzymes involved in neuroinflammation, even in early stages of the disease, is COX-2, an inducible cyclooxygenase responsible for the generation of eicosanoids and for the generation of free radicals. Individuals with Down syndrome develop Alzheimer's disease early in life. Previous studies pointed to the possible overexpression of COX-2 and correlated it to brain regions affected by the disease. We analysed the COX-2 expression levels in individuals with Down syndrome and in young, adult and old mice of the Ts65Dn mouse model for Down syndrome. We have observed an overexpression of COX-2 in both, Down syndrome individuals and mice. Importantly, mice already presented an overexpression of COX-2 at postnatal day 30, before neurodegeneration begins; which suggests that neuroinflammation may underlie the posterior neurodegeneration observed in individuals with Down syndrome and in Ts65Dn mice and could be a factor for the premature appearance of Alzheimer's disease..

Cyclooxygenase-2 Deficiency Leads to Intestinal Barrier Dysfunction and Increased Mortality During Polymicrobial Sepsis 1

PubMed Central

Fredenburgh, Laura E.; Velandia, Margarita M. Suarez; Ma, Jun; Olszak, Torsten; Cernadas, Manuela; Englert, Joshua A.; Chung, Su Wol; Liu, Xiaoli; Begay, Cynthia; Padera, Robert F.; Blumberg, Richard S.; Walsh, Stephen R.; Baron, Rebecca M.; Perrella, Mark A.

2011-01-01

Sepsis remains the leading cause of death in critically ill patients despite modern advances in critical care. Intestinal barrier dysfunction may lead to secondary bacterial translocation and the development of the multiple organ dysfunction syndrome during sepsis. Cyclooxygenase-2 (COX-2) is highly upregulated in the intestine during sepsis and we hypothesized that it may be critical in the maintenance of intestinal epithelial barrier function during peritonitis-induced polymicrobial sepsis. COX-2−/− and COX-2+/+ BALB/c mice underwent cecal ligation and puncture (CLP) or sham surgery. Mice chimeric for COX-2 were derived by bone marrow transplantation and underwent CLP. C2BBe1 cells, an intestinal epithelial cell line, were treated with the COX-2 inhibitor NS-398, PGD2, or vehicle and stimulated with cytokines. COX-2−/− mice developed exaggerated bacteremia and increased mortality compared with COX-2+/+ mice following CLP. Mice chimeric for COX-2 exhibited the recipient phenotype suggesting that epithelial COX-2 expression in the ileum attenuates bacteremia following CLP. Absence of COX-2 significantly increased epithelial permeability of the ileum and reduced expression of the tight junction proteins zonula occludens-1 (ZO-1), occludin, and claudin-1 in the ileum following CLP. Furthermore, PGD2 attenuated cytokine-induced hyperpermeability and ZO-1 downregulation in NS-398-treated C2BBe1 cells. Our findings reveal that absence of COX-2 is associated with enhanced intestinal epithelial permeability and leads to exaggerated bacterial translocation and increased mortality during peritonitis-induced sepsis. Taken together, our results suggest that epithelial expression of COX-2 in the ileum is a critical modulator of tight junction protein expression and intestinal barrier function during sepsis. PMID:21967897

Nonylphenol regulates cyclooxygenase-2 expression via Ros-activated NF-κB pathway in sertoli TM4 cells.

PubMed

Liu, Xiaozhen; Nie, Shaoping; Huang, Danfei; Xie, Mingyong

2015-09-01

The aim of this study was to investigate the signaling pathways involved in the cyclooxygenase (COX)-2 regulation induced by nonylphenol (NP) in mouse testis Sertoli TM4 cells. Our results showed that treatment of TM4 cells with NP increased COX-2 protein expression and interleukin-6 (IL)-6 and prostaglandin E2 (PGE2) secretion in a dose-dependent manner. Pretreatment with reactive oxygen species (ROS) scavenger, N-acetylcysteine (NAC), attenuated NP-induced ROS production, COX-2 expression, and IL-6 and PGE2 release in TM4 cells. Exposure to NP stimulated activation of NF-κB, whereas the NF-κB inhibitor, pyrrolidine dithiocarbamate, attenuated NP-enhanced COX-2 expression and IL-6 and PGE2 release in TM4 cells in a dose-dependent manner. Furthermore, NAC blocked NP-induced activation of NF-κB. In addition, inhibition of COX-2 mitigated NP-induced IL-6 release. In conclusion, NP induced ROS generation, activation of NF-κB pathway, COX-2 upregulation, and IL-6 and PGE2 secretion in TM4 cells. NP may regulate COX-2 expression via ROS-activated NF-κB pathway in Sertoli TM4 cells. © 2014 Wiley Periodicals, Inc.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shim, Su Jung; Yang, Woo-Ick; Shin, Eunah

Purpose: To determine whether there are any differences in therapeutic response, patterns of systemic recurrence, and prognosis of patients with extranodal natural killer (NK)/T-cell lymphoma, nasal type, by the cyclooxygenase-2 (COX-2) expression. Patients and Methods: Thirty-four patients with Ann Arbor Stage I and II extranodal NK/T-cell lymphoma who underwent chemotherapy or radiotherapy, or both, were retrospectively reviewed. These patients were divided into two groups according to their immunohistochemical staining for COX-2 expressions: a COX-2-negative group (n = 10 patients) and a COX-2-positive group (n = 24 patients). The treatment response, patterns of treatment failure, and survival data for the patientsmore » were compared between the COX-2-positive and negative groups. Results: There was no significant difference in the clinical profiles between the COX-2-negative and COX-2-positive groups. All patients (100%) in the COX-2-negative group achieved complete response after initial treatment, whereas only 14 patients (58%) in the COX-2-positive group achieved complete response (p = 0.03). Compared with the patients in the COX-2-negative group, those in the COX-2-positive group had a significantly lower 2-year systemic recurrence-free survival rate (100% for the COX-2-negative group vs. 54% for the COX-2-positive group) (p = 0.02) and a decreased 5-year overall survival rate (70% for the COX-2-negative group vs. 32% for the COX-2-positive group) (p = 0.06). Conclusion: Cyclooxygenase-2 expression can serve as a predictive factor for poor treatment response, higher systemic recurrence, and unfavorable prognosis in patients with extranodal NK/T-cell lymphoma, nasal type.« less

Cyclooxygenase-2 expression in human gastric tubular adenomas and carcinomas; correlation with intratumoral microvessel density and apoptotic index.

PubMed

Honjo, Soichiro; Kase, Satoru; Osaki, Mitsuhiko; Ardyanto, Tonang Dwi; Kaibara, Nobuaki; Ito, Hisao

2004-01-01

Cyclooxygenase (COX)-2 plays an important role in carcinogenesis in various human malignancies. This study examined the relationship among COX-2 expression, angiogenesis and apoptosis in human gastric adenoma and carcinoma. We examined the expression of COX-2 in 30 tubular adenomas and 11 carcinomas, comparing it with intratumoral microvessel density (IMVD) and apoptotic index (AI) by immunohistochemistry and the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-digoxygenin nick-end labeling (TUNEL) procedure. Immunohistochemistry demonstrated positive expression of COX-2 in 15 (50.0%) adenomas and in 50 (53.1%) carcinomas, respectively. The frequency of COX-2 expression was significantly higher in intestinal-type carcinomas than in diffuse-type, regardless of the tumor stage. The IMVD was significantly higher in the early and advanced carcinomas than in the adenomas and also higher in the COX-2-positive adenomas and carcinomas than in the negative ones. The AI was significantly higher in the adenomas than in the carcinomas and also in the COX-2-negative adenomas and intestinal-type early carcinomas than in their positive counterparts, respectively (p < 0.05). The IMVD and AI showed significant inverse correlation in both the adenomas (p=0.02, r=-0.64) and carcinomas (p=0.04, r=-0.18). COX-2 expression might be an early event in gastric tumorigenesis and provide a preferential advantage for tumor cell proliferation because of its vascular-rich microenvironment and escape from tumor cell apoptosis, especially in intestinal-type gastric carcinomas.

Angiogenic function of prostacyclin biosynthesis in human endothelial progenitor cells

PubMed Central

He, Tongrong; Lu, Tong; d’Uscio, Livius V.; Lam, Chen-Fuh; Lee, Hon-Chi; Katusic, Zvonimir S.

2009-01-01

The role of prostaglandins production in the control of regenerative function of endothelial progenitor cells (EPCs) has not been studied. We hypothesized that activation of cyclooxygenase (COX) enzymatic activity and the subsequent production of prostacyclin (PGI2) is an important mechanism responsible for the regenerative function of EPCs. In the present study, we detected high levels of COX-1 protein expression and PGI2 biosynthesis in human EPCs outgrown from blood mononuclear cells. Expression of COX-2 protein was almost undetectable under basal conditions but significantly elevated after treatment with tumor necrosis factor-α. Condition medium derived from EPCs hyperpolarized human coronary artery smooth muscle cells, similar to the effect of the PGI2 analogue iloprost. The proliferation and in vitro tube formation by EPCs were inhibited by the COX inhibitor indomethacin, or by genetic inactivation of COX-1 or PGI2 synthase (PGIS) with small interfering RNA (siRNA). Impaired tube formation and cell proliferation induced by inactivation of COX-1 were rescued by the treatment with iloprost or selective peroxisome-proliferator activated receptor-δ (PPARδ) agonist, GW501516, but not by the selective PGI2 receptor agonist, cicaprost. Down regulation of PPARδ by siRNA also reduced angiogenic capacity of EPCs. Iloprost failed to reverse PPARδ-siRNA-induced impairment of angiogenesis. Furthermore, transfection of PGIS-siRNA, COX-1-siRNA, or PPARδ-siRNA into EPCs decreased the capillary formation in vivo after transplantation of human EPCs into the nude mice. These results suggest that activation of COX-1-PGI2-PPARδ pathway is an important mechanism underlying pro-angiogenic function of EPCs. PMID:18511850

o,p'-DDT induces cyclooxygenase-2 gene expression in murine macrophages: Role of AP-1 and CRE promoter elements and PI3-kinase/Akt/MAPK signaling pathways

DOE Office of Scientific and Technical Information (OSTI.GOV)

Han, Eun Hee; Kim, Ji Young; Kim, Hyung-Kyun

Dichlorodiphenyltrichloroethane (DDT) has been used as an insecticide to prevent the devastation of malaria in tropical zones. However, many reports suggest that DDT may act as an endocrine disruptor and may have possible carcinogenic effects. Cyclooxygenase-2 (COX-2) acts as a link between inflammation and carcinogenesis through its involvement in tumor promotion. In the present study, we examined the effect of o,p'-DDT on COX-2 gene expression and analyzed the molecular mechanism of its activity in murine RAW 264.7 macrophages. Exposure to o,p'-DDT markedly enhanced the production of prostaglandin E{sub 2} (PGE{sub 2}), a major COX-2 metabolite, in murine macrophages. Furthermore, o,p'-DDTmore » dose-dependently increased the levels of COX-2 protein and mRNA. Transfection with human COX-2 promoter construct, electrophoretic mobility shift assays and DNA-affinity protein-binding assay experiments revealed that o,p'-DDT activated the activator protein 1 (AP-1) and cyclic AMP response element (CRE) sites, but not the NF-{kappa}B site. Phosphatidylinositol 3 (PI3)-kinase, its downstream signaling molecule, Akt, and mitogen-activated protein kinases (MAPK) were also significantly activated by the o,p'-DDT-induced AP-1 and CRE activation. These results demonstrate that o,p'-DDT induced COX-2 expression via AP-1 and CRE activation through the PI3-K/Akt/ERK, JNK, and p38 MAP kinase pathways. These findings provide further insight into the signal transduction pathways involved in the carcinogenic effects of o,p'-DDT.« less

Protein kinase Cε regulates nuclear translocation of extracellular signal-regulated kinase, which contributes to bradykinin-induced cyclooxygenase-2 expression.

PubMed

Nakano, Rei; Kitanaka, Taku; Namba, Shinichi; Kitanaka, Nanako; Sugiya, Hiroshi

2018-06-04

The proinflammatory mediator bradykinin stimulated cyclooxygenase-2 (COX-2) expression and subsequently prostaglandin E 2 synthesis in dermal fibroblasts. The involvement of B2 receptors and Gαq in the role of bradykinin was suggested by using pharmacological inhibitors. The PKC activator PMA stimulated COX-2 mRNA expression. Bradykinin failed to induce COX-2 mRNA expression in the presence of PKC inhibitors, whereas the effect of bradykinin was observed in the absence of extracellular Ca 2+ . Bradykinin-induced COX-2 mRNA expression was inhibited in cells transfected with PKCε siRNA. These observations suggest that the novel PKCε is concerned with bradykinin-induced COX-2 expression. Bradykinin-induced PKCε phosphorylation and COX-2 mRNA expression were inhibited by an inhibitor of 3-phosphoinositide-dependent protein kinase-1 (PDK-1), and bradykinin-induced PDK-1 phosphorylation was inhibited by phospholipase D (PLD) inhibitors, suggesting that PLD/PDK-1 pathway contributes to bradykinin-induced PKCε activation. Pharmacological and knockdown studies suggest that the extracellular signal-regulated kinase 1 (ERK1) MAPK signaling is involved in bradykinin-induced COX-2 expression. Bradykinin-induced ERK phosphorylation was attenuated in the cells pretreated with PKC inhibitors or transfected with PKCε siRNA. We observed the interaction between PKCε and ERK by co-immunoprecipitation experiments. These observations suggest that PKCε activation contributes to the regulation of ERK1 activation. Bradykinin stimulated the accumulation of phosphorylated ERK in the nuclear fraction, that was inhibited in the cells treated with PKC inhibitors or transfected with PKCε siRNA. Consequently, we concluded that bradykinin activates PKCε via the PLD/PDK-1 pathway, which subsequently induces activation and translocation of ERK1 into the nucleus, and contributes to COX-2 expression for prostaglandin E 2 synthesis in dermal fibroblasts.

Down-regulation of Cyclooxygenase-2 by the Carboxyl Tail of the Angiotensin II Type 1 Receptor*

PubMed Central

Sood, Rapita; Minzel, Waleed; Rimon, Gilad; Tal, Sharon; Barki-Harrington, Liza

2014-01-01

The enzyme cyclooxygenase-2 (COX-2) plays an important role in the kidney by up-regulating the production of the vasoconstrictor hormone angiotensin II (AngII), which in turn down-regulates COX-2 expression via activation of the angiotensin II type 1 receptor (AT1) receptor. Chemical inhibition of the catalytic activity of COX-2 is a well-established strategy for treating inflammation but little is known of cellular mechanisms that dispose of the protein itself. Here we show that in addition to its indirect negative feedback on COX-2, AT1 also down-regulates the expression of the COX-2 protein via a pathway that does not involve G-protein or β-arrestin-dependent signaling. Instead, AT1 enhances the ubiquitination and subsequent degradation of the enzyme in the proteasome through elements in its cytosolic carboxyl tail (CT). We find that a mutant receptor that lacks the last 35 amino acids of its CT (Δ324) is devoid of its ability to reduce COX-2, and that expression of the CT sequence alone is sufficient to down-regulate COX-2. Collectively these results propose a new role for AT1 in regulating COX-2 expression in a mechanism that deviates from its canonical signaling pathways. Down-regulation of COX-2 by a short peptide that originates from AT1 may present as a basis for novel therapeutic means of eliminating excess COX-2 protein. PMID:25231994

Cyclic stretch induces cyclooxygenase-2 gene expression in vascular endothelial cells via activation of nuclear factor kappa-{beta}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Haige; Hiroi, Toyoko; Hansen, Baranda S.

2009-11-27

Vascular endothelial cells respond to biomechanical forces, such as cyclic stretch and shear stress, by altering gene expression. Since endothelial-derived prostanoids, such as prostacyclin and thromboxane A{sub 2}, are key mediators of endothelial function, we investigated the effects of cyclic stretch on the expression of genes in human umbilical vein endothelial cells controlling prostanoid synthesis: cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), prostacyclin synthase (PGIS) and thromboxane A{sub 2} synthase (TXAS). COX-2 and TXAS mRNAs were upregulated by cyclic stretch for 24 h. In contrast, PGIS mRNA was decreased and stretch had no effect on COX-1 mRNA expression. We further show that stretch-inducedmore » upregulation of COX-2 is mediated by activation of the NF-{kappa}{beta} signaling pathway.« less

Nimesulide, a cyclooxygenase-2 selective inhibitor, suppresses obesity-related non-alcoholic fatty liver disease and hepatic insulin resistance through the regulation of peroxisome proliferator-activated receptor γ

PubMed Central

Tsujimoto, Shunsuke; Kishina, Manabu; Koda, Masahiko; Yamamoto, Yasutaka; Tanaka, Kohei; Harada, Yusuke; Yoshida, Akio; Hisatome, Ichiro

2016-01-01

Cyclooxygenase (COX)-2 selective inhibitors suppress non-alcoholic fatty liver disease (NAFLD); however, the precise mechanism of action remains unknown. The aim of this study was to examine how the COX-2 selective inhibitor nimesulide suppresses NAFLD in a murine model of high-fat diet (HFD)-induced obesity. Mice were fed either a normal chow diet (NC), an HFD, or HFD plus nimesulide (HFD-nime) for 12 weeks. Body weight, hepatic COX-2 mRNA expression and triglyceride accumulation were significantly increased in the HFD group. Triglyceride accumulation was suppressed in the HFD-nime group. The mRNA expression of hepatic peroxisome proliferator-activated receptor γ (PPARγ) and the natural PPARγ agonist 15-deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2) were significantly increased in the HFD group and significantly suppressed in the HFD-nime group. Glucose metabolism was impaired in the HFD group compared with the NC group, and it was significantly improved in the HFD-nime group. In addition, the plasma insulin levels in the HFD group were increased compared with those in the NC group, and were decreased in the HFD-nime group. These results indicate that HFD-induced NAFLD is mediated by the increased hepatic expression of COX-2. We suggest that the production of 15d-PGJ2, which is mediated by COX-2, induces NAFLD and hepatic insulin resistance by activating PPARγ. Furthermore, the mRNA expression of tissue inhibitor of metalloproteinases-1 (TIMP-1), procollagen-1 and monocyte chemoattractant protein-1 (MCP-1), as well as the number of F4/80-positive hepatic (Kupffer) cells, were significantly increased in the HFD group compared with the NC group, and they were reduced by nimesulide. In conclusion, COX-2 may emerge as a molecular target for preventing the development of NAFLD and insulin resistance in diet-related obesity. PMID:27431935

Vitamin C down-regulates VEGF production in B16F10 murine melanoma cells via the suppression of p42/44 MAPK activation.

PubMed

Kim, Ha Na; Kim, Hyemin; Kong, Joo Myung; Bae, Seyeon; Kim, Yong Sung; Lee, Naeun; Cho, Byung Joo; Lee, Seung Koo; Kim, Hang-Rae; Hwang, Young-il; Kang, Jae Seung; Lee, Wang Jae

2011-03-01

It is known that vitamin C induces apoptosis in several kinds of tumor cells, but its effect on the regulation of the angiogenic process of tumors is not completely studied. Vascular endothelial growth factor (VEGF) is the most well-known angiogenic factor, and it has a potent function as a stimulator of endothelial survival, migration, as well as vascular permeability. Therefore, we have investigated whether vitamin C can regulate the angiogenic process through the modulation of VEGF production from B16F10 melanoma cells. VEGF mRNA expression and VEGF production at protein levels were suppressed by vitamin C. In addition, we found that vitamin C suppressed the expression of cyclooxygenase (COX)-2 and that decreased VEGF production by vitamin C was also restored by the administration of prostaglandin E2 which is a product of COX-2. These results suggest that vitamin C suppresses VEGF expression via the regulation of COX-2 expression. Mitogen-activated protein kinases are generally known as key mediators in the signaling pathway for VEGF production. In the presence of vitamin C, the activation of p42/44 MAPK was completely inhibited. Taken together, our data suggest that vitamin C can down-regulate VEGF production via the modulation of COX-2 expression and that p42/44 MAPK acts as an important signaling mediator in this process. Copyright © 2010 Wiley-Liss, Inc.

The HGF Receptor c-Met Is Overexpressed in Esophageal Adenocarcinoma1

PubMed Central

Herrera, Luis J; El-Hefnawy, Talal; Queiroz de Oliveira, Pierre E; Raja, Siva; Finkelstein, Sydney; Gooding, William; Luketich, James D; Godfrey, Tony E; Hughes, Steven J

2005-01-01

Abstract The hepatocyte growth factor (HGF) receptor, Met, has established oncogenic properties; however, its expression and function in esophageal adenocarcinoma (EA) remain poorly understood. We aimed to determine the expression and potential alterations in Met expression in EA. Met expression was investigated in surgical specimens of EA, Barrett's esophagus (BE), and normal esophagus (NE) using immunohistochemistry (IHC) and quantitative reverse transcriptase polymerase chain reaction. Met expression, phosphorylation, and the effect of COX-2 inhibition on expression were examined in EA cell lines. IHC demonstrated intense Met immunoreactivity in all (100%) EA and dysplastic BE specimens. In contrast, minimal immunostaining was observed in BE without dysplasia or NE specimens. Met mRNA and protein levels were increased in three EA cell lines, and Met protein was phosphorylated in the absence of serum. Sequence analysis found the kinase domain of c-met to be wild type in all three EA cell lines. HGF mRNA expression was identified in two EA cell lines. In COX-2-overexpressing cells, COX-2 inhibition decreased Met expression. Met is consistently overexpressed in EA surgical specimens and in three EA cell lines. Met dysregulation occurs early in Barrett's dysplasia to adenocarcinoma sequence. Future study of Met inhibition as a potential biologic therapy for EA is warranted. PMID:15720819

A miR-335/COX-2/PTEN axis regulates the secretory phenotype of senescent cancer-associated fibroblasts

PubMed Central

Kabir, Tasnuva D.; Leigh, Ross J.; Tasena, Hataitip; Mellone, Massimiliano; Coletta, Ricardo D.; Parkinson, Eric K.; Prime, Stephen S.; Thomas, Gareth J.; Paterson, Ian C.; Zhou, Donghui; McCall, John; Speight, Paul M.; Lambert, Daniel W.

2016-01-01

Senescent cancer-associated fibroblasts (CAF) develop a senescence-associated secretory phenotype (SASP) that is believed to contribute to cancer progression. The mechanisms underlying SASP development are, however, poorly understood. Here we examined the functional role of microRNA in the development of the SASP in normal fibroblasts and CAF. We identified a microRNA, miR-335, up-regulated in the senescent normal fibroblasts and CAF and able to modulate the secretion of SASP factors and induce cancer cell motility in co-cultures, at least in part by suppressing the expression of phosphatase and tensin homologue (PTEN). Additionally, elevated levels of cyclo-oxygenase 2 (PTGS2; COX-2) and prostaglandin E2 (PGE2) secretion were observed in senescent fibroblasts, and inhibition of COX-2 by celecoxib reduced the expression of miR-335, restored PTEN expression and decreased the pro-tumourigenic effects of the SASP. Collectively these data demonstrate the existence of a novel miRNA/PTEN-regulated pathway modulating the inflammasome in senescent fibroblasts. PMID:27385366

Inhibitory effect of interferon-α-2b on expression of cyclooxygenase-2 and vascular endothelial growth factor in human hepatocellular carcinoma inoculated in nude mice

PubMed Central

Cao, Bin; Chen, Xiao-Ping; Zhu, Peng; Ding, Lei; Guan, Jian; Shi, Zuo-Liang

2008-01-01

AIM: To evaluate the effects of interferon-α-2b (IFN-α-2b) on expression of cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF) in human hepatocellular carcinoma (HCC) inoculated in nude mice and to study the underlying mechanism of IFN-α-2b against HCC growth. METHODS: Thirty-two nude mice bearing human HCC were randomly divided into four groups (n = 8). On the 10th day after implantation of HCC cells, the mice in test groups (groups A, B and C) received IFN-α-2b at a serial dose (10 000 IU for group A, 20 000 IU for group B, 40 000 IU for group C sc daily) for 35 d. The mice in control group received normal saline (NS). The growth conditions of transplanted tumors were observed. Both genes and proteins of COX-2 and VEGF were detected by RT-PCR and Western blot. Apoptosis of tumor cells in nude mice was detected by TUNEL assay after treatment with IFN-α-2b. RESULTS: Tumors were significantly smaller and had a lower weight in the IFN-α-2b treatment groups than those in the control group (P < 0.01), and the tumor growth inhibition rate in groups A, B and C was 27.78%, 65.22% and 49.64%, respectively. The expression levels of both genes and proteins of COX-2 and VEGF were much lower in the IFN-α-2b treatment groups than in the control group (P < 0.01). The apoptosis index (AI) of tumor cells in the IFN-α-2b treatment groups was markedly higher than that in the control group (P < 0.01). Group B had a higher inhibition rate of tumor growth, a lower expression level of COX-2 and VEGF and a higher AI than groups A and C (P < 0.05), but there was no significant difference between groups A and C. CONCLUSION: The inhibitory effects of IFN-α-2b on implanted tumor growth and apoptosis may be associated with the down-regulation of COX-2 and VEGF expression. There is a dose-effect relationship. The medium dose of IFN-α-2b for inhibiting tumor growth is 20 000 IU/d. PMID:19058305

Nitric Oxide Synthase and Cyclooxygenase Pathways: A Complex Interplay in Cellular Signaling.

PubMed

Sorokin, Andrey

2016-01-01

The cellular reaction to external challenges is a tightly regulated process consisting of integrated processes mediated by a variety of signaling molecules, generated as a result of modulation of corresponding biosynthetic systems. Both, nitric oxide synthase (NOS) and cyclooxygenase (COX) systems, consist of constitutive forms (NOS1, NOS3 and COX-1), which are mostly involved in housekeeping tasks, and inducible forms (NOS2 and COX-2), which shape the cellular response to stress and variety of bioactive agents. The complex interplay between NOS and COX pathways can be observed at least at three levels. Firstly, products of NOS and Cox systems can mediate the regulation and the expression of inducible forms (NOS2 and COX-2) in response of similar and dissimilar stimulus. Secondly, the reciprocal modulation of cyclooxygenase activity by nitric oxide and NOS activity by prostaglandins at the posttranslational level has been shown to occur. Mechanisms by which nitric oxide can modulate prostaglandin synthesis include direct S-nitrosylation of COX and inactivation of prostaglandin I synthase by peroxynitrite, product of superoxide reaction with nitric oxide. Prostaglandins, conversely, can promote an increased association of dynein light chain (DLC) (also known as protein inhibitor of neuronal nitric oxide synthase) with NOS1, thereby reducing its activity. The third level of interplay is provided by intracellular crosstalk of signaling pathways stimulated by products of NOS and COX which contributes significantly to the complexity of cellular signaling. Since modulation of COX and NOS pathways was shown to be principally involved in a variety of pathological conditions, the dissection of their complex relationship is needed for better understanding of possible therapeutic strategies. This review focuses on implications of interplay between NOS and COX for cellular function and signal integration.

Effect of topical application of quercetin-3-O-(2″-gallate)-α-l-rhamnopyranoside on atopic dermatitis in NC/Nga mice.

PubMed

Park, Eun Joo; Kim, Ji-Yun; Jeong, Mi Sook; Park, Kui Young; Park, Kwan Hee; Lee, Min Won; Joo, Seong Soo; Seo, Seong Jun

2015-03-01

Quercetin-3-O-(2″-gallate)-α-l-rhamnopyranoside (QGR) is a new quercetin derivative which is isolated from the leaves of Acer ginnala Maxim, a native plant of Korea. Quercetin has several biological effects including antioxidative, anti-inflammatory, and anti-allergic effects. However, the topical effect of QGR on atopic dermatitis (AD) like skin lesion in NC/Nga mice has not been studied. To evaluate the anti-inflammatory and anti-allergic effect of QGR in a murine model of atopic dermatitis. We measured inducible nitric oxide synthase (iNOS) and cyclooxygenase -2(COX-2) level in RAW264.7 cell with QGR treatment. And after induction of AD like skin lesions with Dermatophagoides farina (Df) ointment, mice were treated with QGR and control drugs. Clinical scores, interleukin (IL) 4, 5, and 13, serum IgE, eosinophil levels, iNOS and COX-2 level were evaluated. Results show that mRNA level of iNOS and COX-2 in vitro were decreased after QGR treatment. Topical QGR markedly decreased the iNOS and COX-2 mRNA expressions in the skin. QGR also significantly suppressed the increase in the level of total plasma IgE and eosinophils. In addition, topical application of QGR down-regulated the expressions of the cytokines, IL-4,5 and 13, which were induced by Df ointment stimulation. In the present study, we showed that topical application of QGR ameliorated Df-induced AD-like inflammatory responses in NC/Nga mice. These results demonstrate that QGR might be beneficial in the treatment of AD. Copyright © 2015 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

Myeloid Cell COX-2 deletion reduces mammary tumor growth through enhanced cytotoxic T-lymphocyte function

PubMed Central

Chen, Edward P.; Markosyan, Nune; Connolly, Emma; Lawson, John A.; Li, Xuanwen; Grant, Gregory R.; Grosser, Tilo; FitzGerald, Garret A.; Smyth, Emer M.

2014-01-01

Cyclooxygenase-2 (COX-2) expression is associated with poor prognosis across a range of human cancers, including breast cancer. The contribution of tumor cell-derived COX-2 to tumorigenesis has been examined in numerous studies; however, the role of stromal-derived COX-2 is ill-defined. Here, we examined how COX-2 in myeloid cells, an immune cell subset that includes macrophages, influences mammary tumor progression. In mice engineered to selectively lack myeloid cell COX-2 [myeloid-COX-2 knockout (KO) mice], spontaneous neu oncogene-induced tumor onset was delayed, tumor burden reduced, and tumor growth slowed compared with wild-type (WT). Similarly, growth of neu-transformed mammary tumor cells as orthotopic tumors in immune competent syngeneic myeloid-COX-2 KO host mice was reduced compared with WT. By flow cytometric analysis, orthotopic myeloid-COX-2 KO tumors had lower tumor-associated macrophage (TAM) infiltration consistent with impaired colony stimulating factor-1-dependent chemotaxis by COX-2 deficient macrophages in vitro. Further, in both spontaneous and orthotopic tumors, COX-2-deficient TAM displayed lower immunosuppressive M2 markers and this was coincident with less suppression of CD8+ cytotoxic T lymphocytes (CTLs) in myeloid-COX-2 KO tumors. These studies suggest that reduced tumor growth in myeloid-COX-2 KO mice resulted from disruption of M2-like TAM function, thereby enhancing T-cell survival and immune surveillance. Antibody-mediated depletion of CD8+, but not CD4+ cells, restored tumor growth in myeloid-COX-2 KO to WT levels, indicating that CD8+ CTLs are dominant antitumor effectors in myeloid-COX-2 KO mice. Our studies suggest that inhibition of myeloid cell COX-2 can potentiate CTL-mediated tumor cytotoxicity and may provide a novel therapeutic approach in breast cancer therapy. PMID:24590894

Azilsartan Increases Levels of IL-10, Down-Regulates MMP-2, MMP-9, RANKL/RANK, Cathepsin K and Up-Regulates OPG in an Experimental Periodontitis Model

PubMed Central

Brito, Gerly Anne de Castro; de Medeiros, Caroline Addison Carvalho Xavier; Araújo, Lorena de Souza; do Nascimento, José Heriberto Oliveira; de Araújo Júnior, Raimundo Fernandes

2014-01-01

Aims The aim of this study was to evaluate the effects of azilsartan (AZT) on bone loss, inflammation, and the expression of matrix metallo proteinases (MMPs), receptor activator of nuclear factor κB ligand (RANKL), receptor activator of nuclear factor κB (RANK), osteoprotegerin (OPG), cyclooxygenase-2 (COX-2), and cathepsin K in periodontal tissue in a rat model of ligature-induced periodontitis. Materials and Methods Male Wistar albino rats were randomly divided into 5 groups of 10 rats each: (1) nonligated, water; (2) ligated, water; (3) ligated, 1 mg/kg AZT; (4) ligated, 5 mg/kg AZT; and (5) ligated, 10 mg/kg AZT. All groups were treated with saline or AZT for 10 days. Periodontal tissues were analyzed by histopathology and immunohistochemical detection of MMP-2, MMP-9, COX-2, RANKL, RANK, OPG, and cathepsin K. Levels of IL-1β, IL-10, TNF-α, myeloperoxidase (MPO), and glutathione (GSH) were determined by ELISA. Results Treatment with 5 mg/kg AZT resulted in reduced MPO (p<0.05) and IL-1β (p<0.05), increased levels of IL-10 (p<0.05), and reduced expression of MMP-2, MMP-9, COX-2, RANK, RANKL, cathepsin K, and increased expression of OPG. Conclusions These findings reveal that AZT increases anti-inflammatory cytokines and GSH and decreases bone loss in ligature-induced periodontitis in rats. PMID:24819928

Induction of cyclo-oxygenase-2 mRNA by prostaglandin E2 in human prostatic carcinoma cells

NASA Technical Reports Server (NTRS)

Tjandrawinata, R. R.; Dahiya, R.; Hughes-Fulford, M.

1997-01-01

Prostaglandins are synthesized from arachidonic acid by the enzyme cyclo-oxygenase. There are two isoforms of cyclooxygenases: COX-1 (a constitutive form) and COX-2 (an inducible form). COX-2 has recently been categorized as an immediate-early gene and is associated with cellular growth and differentiation. The purpose of this study was to investigate the effects of exogenous dimethylprostaglandin E2 (dmPGE2) on prostate cancer cell growth. Results of these experiments demonstrate that administration of dmPGE2 to growing PC-3 cells significantly increased cellular proliferation (as measured by the cell number), total DNA content and endogenous PGE2 concentration. DmPGE2 also increased the steady-state mRNA levels of its own inducible synthesizing enzyme, COX-2, as well as cellular growth to levels similar to those seen with fetal calf serum and phorbol ester. The same results were observed in other human cancer cell types, such as the androgen-dependent LNCaP cells, breast cancer MDA-MB-134 cells and human colorectal carcinoma DiFi cells. In PC-3 cells, the dmPGE2 regulation of the COX-2 mRNA levels was both time dependent, with maximum stimulation seen 2 h after addition, and dose dependent on dmPGE2 concentration, with maximum stimulation seen at 5 microg ml(-1). The non-steroidal anti-inflammatory drug flurbiprofen (5 microM), in the presence of exogenous dmPGE2, inhibited the up-regulation of COX-2 mRNA and PC-3 cell growth. Taken together, these data suggest that PGE2 has a specific role in the maintenance of human cancer cell growth and that the activation of COX-2 expression depends primarily upon newly synthesized PGE2, perhaps resulting from changes in local cellular PGE2 concentrations.

IL-1β Stimulates COX-2 Dependent PGE2 Synthesis and CGRP Release in Rat Trigeminal Ganglia Cells

PubMed Central

Neeb, Lars; Hellen, Peter; Boehnke, Carsten; Hoffmann, Jan; Schuh-Hofer, Sigrid; Dirnagl, Ulrich; Reuter, Uwe

2011-01-01

Objective Pro-inflammatory cytokines like Interleukin-1 beta (IL-1β) have been implicated in the pathophysiology of migraine and inflammatory pain. The trigeminal ganglion and calcitonin gene-related peptide (CGRP) are crucial components in the pathophysiology of primary headaches. 5-HT1B/D receptor agonists, which reduce CGRP release, and cyclooxygenase (COX) inhibitors can abort trigeminally mediated pain. However, the cellular source of COX and the interplay between COX and CGRP within the trigeminal ganglion have not been clearly identified. Methods and Results 1. We used primary cultured rat trigeminal ganglia cells to assess whether IL-1β can induce the expression of COX-2 and which cells express COX-2. Stimulation with IL-1β caused a dose and time dependent induction of COX-2 but not COX-1 mRNA. Immunohistochemistry revealed expression of COX-2 protein in neuronal and glial cells. 2. Functional significance was demonstrated by prostaglandin E2 (PGE2) release 4 hours after stimulation with IL-1β, which could be aborted by a selective COX-2 (parecoxib) and a non-selective COX-inhibitor (indomethacin). 3. Induction of CGRP release, indicating functional neuronal activation, was seen 1 hour after PGE2 and 24 hours after IL-1β stimulation. Immunohistochemistry showed trigeminal neurons as the source of CGRP. IL-1β induced CGRP release was blocked by parecoxib and indomethacin, but the 5-HT1B/D receptor agonist sumatriptan had no effect. Conclusion We identified a COX-2 dependent pathway of cytokine induced CGRP release in trigeminal ganglia neurons that is not affected by 5-HT1B/D receptor activation. Activation of neuronal and glial cells in the trigeminal ganglion by IL-β leads to an elevated expression of COX-2 in these cells. Newly synthesized PGE2 (by COX-2) in turn activates trigeminal neurons to release CGRP. These findings support a glia-neuron interaction in the trigeminal ganglion and demonstrate a sequential link between COX-2 and CGRP. The results could help to explain the mechanism of action of COX-2 inhibitors in migraine. PMID:21394197

COX-2 and PPAR-γ confer cannabidiol-induced apoptosis of human lung cancer cells.

PubMed

Ramer, Robert; Heinemann, Katharina; Merkord, Jutta; Rohde, Helga; Salamon, Achim; Linnebacher, Michael; Hinz, Burkhard

2013-01-01

The antitumorigenic mechanism of cannabidiol is still controversial. This study investigates the role of COX-2 and PPAR-γ in cannabidiol's proapoptotic and tumor-regressive action. In lung cancer cell lines (A549, H460) and primary cells from a patient with lung cancer, cannabidiol elicited decreased viability associated with apoptosis. Apoptotic cell death by cannabidiol was suppressed by NS-398 (COX-2 inhibitor), GW9662 (PPAR-γ antagonist), and siRNA targeting COX-2 and PPAR-γ. Cannabidiol-induced apoptosis was paralleled by upregulation of COX-2 and PPAR-γ mRNA and protein expression with a maximum induction of COX-2 mRNA after 8 hours and continuous increases of PPAR-γ mRNA when compared with vehicle. In response to cannabidiol, tumor cell lines exhibited increased levels of COX-2-dependent prostaglandins (PG) among which PGD(2) and 15-deoxy-Δ(12,14)-PGJ(2) (15d-PGJ(2)) caused a translocation of PPAR-γ to the nucleus and induced a PPAR-γ-dependent apoptotic cell death. Moreover, in A549-xenografted nude mice, cannabidiol caused upregulation of COX-2 and PPAR-γ in tumor tissue and tumor regression that was reversible by GW9662. Together, our data show a novel proapoptotic mechanism of cannabidiol involving initial upregulation of COX-2 and PPAR-γ and a subsequent nuclear translocation of PPAR-γ by COX-2-dependent PGs.

Staurosporine synergistically potentiates the deoxycholate-mediated induction of COX-2 expression.

PubMed

Saeki, Tohru; Inui, Haruka; Fujioka, Saya; Fukuda, Suguru; Nomura, Ayumi; Nakamura, Yasushi; Park, Eun Young; Sato, Kenji; Kanamoto, Ryuhei

2014-08-01

Colorectal cancer is a major cause of cancer-related death in western countries, and thus there is an urgent need to elucidate the mechanism of colorectal tumorigenesis. A diet that is rich in fat increases the risk of colorectal tumorigenesis. Bile acids, which are secreted in response to the ingestion of fat, have been shown to increase the risk of colorectal tumors. The expression of cyclooxygenase (COX)-2, an inducible isozyme of cyclooxygenase, is induced by bile acids and correlates with the incidence and progression of cancers. In this study, we investigated the signal transduction pathways involved in the bile-acid-mediated induction of COX-2 expression. We found that staurosporine (sts), a potent protein kinase C (PKC) inhibitor, synergistically potentiated the deoxycholate-mediated induction of COX-2 expression. Sts did not increase the stabilization of COX-2 mRNA. The sts- and deoxycholate-mediated synergistic induction of COX-2 expression was suppressed by a membrane-permeable Ca(2+) chelator, a phosphoinositide 3-kinase inhibitor, a nuclear factor-κB pathway inhibitor, and inhibitors of canonical and stress-inducible mitogen-activated protein kinase pathways. Inhibition was also observed using PKC inhibitors, suggesting the involvement of certain PKC isozymes (η, θ, ι, ζ, or μ). Our results indicate that sts exerts its potentiating effects via the phosphorylation of p38. However, the effects of anisomycin did not mimic those of sts, indicating that although p38 activation is required, it does not enhance deoxycholate-induced COX-2 expression. We conclude that staurosporine synergistically enhances deoxycholate-induced COX-2 expression in RCM-1 colon cancer cells. © 2014 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

Control of human energy expenditure by cytochrome c oxidase subunit IV-2.

PubMed

Schiffer, Tomas A; Peleli, Maria; Sundqvist, Michaela L; Ekblom, Björn; Lundberg, Jon O; Weitzberg, Eddie; Larsen, Filip J

2016-09-01

Resting metabolic rate (RMR) in humans shows pronounced individual variations, but the underlying molecular mechanism remains elusive. Cytochrome c oxidase (COX) plays a key role in control of metabolic rate, and recent studies of the subunit 4 isoform 2 (COX IV-2) indicate involvement in the cellular response to hypoxia and oxidative stress. We evaluated whether the COX subunit IV isoform composition may explain the pronounced individual variations in resting metabolic rate (RMR). RMR was determined in healthy humans by indirect calorimetry and correlated to levels of COX IV-2 and COX IV-1 in vastus lateralis. Overexpression and knock down of the COX IV isoforms were performed in primary myotubes followed by evaluation of the cell respiration and production of reactive oxygen species. Here we show that COX IV-2 protein is constitutively expressed in human skeletal muscle and strongly correlated to RMR. Primary human myotubes overexpressing COX IV-2 displayed markedly (>60%) lower respiration, reduced (>50%) cellular H2O2 production, higher resistance toward both oxidative stress, and severe hypoxia compared with control cells. These results suggest an important role of isoform COX IV-2 in the control of energy expenditure, hypoxic tolerance, and mitochondrial ROS homeostasis in humans. Copyright © 2016 the American Physiological Society.

Involvement of hypothalamic cyclooxygenase-2, interleukin-1β and melanocortin in the development of docetaxel-induced anorexia in rats.

PubMed

Yamamoto, Kouichi; Asano, Keiko; Ito, Yui; Matsukawa, Naoki; Kim, Seikou; Yamatodani, Atsushi

2012-12-16

Docetaxel, a taxane derivative, is frequently used for the treatment of advanced breast cancer, non-small cell lung cancer, and metastatic prostate cancer. Clinical reports demonstrated that docetaxel-based chemotherapy often induces anorexia, but the etiology is not completely understood. To elucidate possible mechanisms, we investigated the involvement of central interleukin (IL)-1β, cyclooxygenase (COX)-2, and pro-opiomelanocortin (POMC) in the development of docetaxel-induced anorexia in rats. Rats received docetaxel (10mg/kg, i.p.) with or without pretreatment with selective COX-2 inhibitors, NS-398 (10 and 30 mg/kg, i.g.) or celecoxib (10 and 30 mg/kg, i.g.), and a non-selective COX inhibitor, indomethacin (10mg/kg, i.g.), then food intake was monitored for 24h after administration. We also examined expression of IL-1β, COX-2, and POMC mRNA in hypothalamus of docetaxel-treated rats and the effect of a COX-2 inhibitor on docetaxel-induced POMC mRNA expression. Food consumption in rats was significantly decreased 24h after administration of docetaxel and anorexia was partially reversed by all COX inhibitors. Administration of docetaxel increased IL-1β, COX-2, and POMC mRNA expression in the hypothalamus of rats. The time required to increase these gene expressions was comparable to the latency period of docetaxel-induced anorexia in rats. In addition, pretreatment with COX-2 inhibitors suppressed docetaxel-induced expression of POMC mRNA. These results suggest that IL-1β and COX-2 mRNA expression and subsequent activation of POMC in the hypothalamus may contribute to the development of docetaxel-induced anorexia in rats. Copyright © 2012. Published by Elsevier Ireland Ltd.

Constitutive hypophosphorylation of extracellular signal-regulated kinases-1/2 and down-regulation of c-Jun in human gastric adenocarcinoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, William Ka Kei; Department of Medicine and Therapeutics, Chinese University of Hong Kong, Hong Kong; Institute of Digestive Diseases, Chinese University of Hong Kong, Hong Kong

2008-08-22

Hyperphosphorylation of extracellular signal-regulated protein kinases-1/2 (ERK1/2) is known to promote cancer cell proliferation. We therefore investigated the constitutive phosphorylation levels of ERK1/2 and the expression of its downstream targets c-Fos, c-Jun, and cyclooxygenase-2 (COX-2) in biopsied human gastric cancer tissues. Results showed that ERK1/2 phosphorylation and c-Jun expression were significantly lowered in gastric cancer compared with the non-cancer adjacent tissues. The expression of c-Fos, however, was not altered while COX-2 was significantly up-regulated. To conclude, we demonstrate that hypophosphorylation of ERK1/2 may occur in gastric cancer. Such discovery may have implication in the application of pathway-directed therapy for thismore » malignant disease.« less

The Role of COX-2 in the Inflammatory and Fibrotic Response in the Lung Following Exposure to Multi-Walled Carbon Nanotubes

NASA Astrophysics Data System (ADS)

Sayers, Brian C.

Exposure to multiwalled carbon nanotubes (MWCNT) has been demonstrated to exacerbate airway inflammation and fibrosis in allergen-challenged mouse model. These data have led to concern that individuals with asthma could represent a susceptible population to adverse health effects following exposure to MWCNT, and possibly other engineered nanoparticles. Asthma pathogenesis is caused by the interaction of a complex genetic predisposition and environmental exposures. Because chronic airway inflammation is common to all asthma phenotypes, it is logical to investigate genes that are involved in inflammatory pathways in order to understand the genetic basis of asthma. The metabolism of arachidonic acid by cyclooxygenase (COX) enzymes is the rate-determining step in the synthesis of prostanoids, which are biologically active lipids that are important modulators of inflammation. Based on the role of COX enzymes in inflammatory pathways, we sought to investigate how COX enzymes are involved in the inflammatory response following MWCNT exposure in asthmatic airways. We report that MWCNT significantly exacerbated allergen-induced airway inflammation and mucus cell metaplasia in COX-2 deficient mice compared to wild type mice. In addition, MWCNTs significantly enhanced allergen-induced cytokines involved in Th2 (IL-13, IL-5), Th1 (CXCL10), and Th17 (IL-17A) inflammatory responses in COX-2 deficient mice but not in WT mice. We conclude that exacerbation of allergen-induced airway inflammation and mucus cell metaplasia by MWCNTs is enhanced by deficiency in COX-2 and associated with activation of a mixed Th1/Th2/Th17 immune response. Based on our observation that COX-2 deficient mice developed a mixed Th immune response following MWCNT exposure, we sought to evaluate how cytokines associated with different Th immune responses alter COX expression following MWCNT exposure. For this study, a mouse macrophage cell line (RAW264.7) was used because MWCNT were largely sequestered within alveolar macrophages with 24 hours after aspiration in mice. We report that the Th1 cytokine interferon gamma (IFNgamma) causes decreased COX-1 expression but increased prostaglandin E2 (PGE 2) production in mouse macrophages exposed to nickel nanoparticles (NiNP), a residual impurity found in MWCNT from the catalytic synthesis process. NiNP exposure alone increased COX-2 and decreased COX-1 in the absence of exogenous cytokines. IFNgamma further reduced COX-1 levels suppressed by NiNP. IL-4, IL-13, or IL-17 did not reduce COX-1 expression alone or in combination with NiNP. Exogenous PGE2 enhanced NiNP- or IFN-gamma-mediated COX-1 suppression. Pharmacologic inhibition of ERK1,2 or JAK/STAT-1 cell signaling pathways inhibited PGE2 production in all dose groups and restored COX-1 expression in cells treated with IFNgamma and NiNP. These data show that PGE2 production is induced in macrophages exposed to IFNgamma and NiNP and suggest that macrophages could be an important source of the anti-inflammatory mediator PGE2 following nanoparticle exposure in a Th1 immune microenvironment. In summary, these studies highlight an important role for COX enzymes in regulating inflammation in response to engineered nanoparticles and show that prostanoid production in response to nanoparticle exposure could be determined in part by the Th immune microenvironment.

Prostacyclin induction by high-density lipoprotein (HDL) in vascular smooth muscle cells depends on sphingosine 1-phosphate receptors: effect of simvastatin.

PubMed

González-Díez, María; Rodríguez, Cristina; Badimon, Lina; Martínez-González, José

2008-07-01

Prostacyclin (PGI2) is an important regulator of vascular homeostasis. Our goal was to analyze the role of sphingosine 1-phosphate (S1P) and its receptors in the up-regulation of cyclooxygenase-2 (Cox-2) induced by HDL in human vascular smooth muscle cells (VSMC). S1P induces Cox-2 expression in a time-and dose-dependent manner at concentrations (0.02-1 microM) compatible with those present in physiological HDL levels. The effect was mimicked by dihydro-S1P (DhS1P), a S1P derivative that only acts through cell surface S1P receptors. Desensitization of S1P receptors with S1P (or DhS1P) abolished HDL-induced Cox-2 up-regulation and PGI2 release. Inhibition of S1P receptors by suramin (inhibitor of S1P3), JTE013 (inhibitor of S1P2) or VPC23019 (inhibitor of S1P1 and S1P3) reduced the up-regulation of Cox-2 induced by HDL and S1P. The combination of suramin and JTE013 increased the inhibitory effect compared to that observed in cells treated with each inhibitor alone. siRNA against S1P2 or S1P3 significantly reduced the ability of HDL and S1P to up-regulate Cox-2. Simvastatin induced over-expression of S1P3 and potentiated the induction of Cox-2 expression produced by HDL (or S1P). Finally, suramin, JTE013 and VPC23019 inhibited p38 MAPK and ERK1/2 signaling pathways activated by HDL (or S1P) and the downstream activation of CREB, a key transcription factor involved in Cox-2 transcriptional up-regulation. These results indicate that S1P receptors, in particular S1P2 and S1P3, are involved in the Cox-2-dependent effects of HDL on vascular cells. Strategies aimed to therapeutically modulate S1P or S1P receptors could be useful to improve cardiovascular protection.

Eicosapentaenoic and docosahexaenoic acids have different effects on peripheral phospholipase A2 gene expressions in acute depressed patients.

PubMed

Su, Kuan-Pin; Yang, Hui-Ting; Chang, Jane Pei-Chen; Shih, Yin-Hua; Guu, Ta-Wei; Kumaran, Satyanarayanan Senthil; Gałecki, Piotr; Walczewska, Anna; Pariante, Carmine M

2018-01-03

Omega-3 polyunsaturated fatty acids (PUFAs) have been proven critical in the development and management of major depressive disorder (MDD) by a number of epidemiological, clinical and preclinical studies, but the molecular mechanisms underlying this therapeutic action are yet to be understood. Although eicosapentaenoic acid (EPA) seems to be the active component of omega-3 PUFAs' antidepressant effects, the biological research about the difference of specific genetic regulations between EPA and docosahexaenoic acid (DHA), the two main components of omega-3 PUFAs, is still lacking in human subjects. We conducted a 12-week randomized-controlled trial comparing the effects of EPA and DHA on gene expressions of phospholipase A2 (cPLA2) and cyclooxygenase-2 (COX2), serotonin transporter (5HTT), and Tryptophan hydroxylase 2 (TPH-2) in 27 MDD patients. In addition, the erythrocyte PUFA compositions and the candidate gene expressions were also compared between these 27 MDD patients and 22 healthy controls. EPA was associated with a significant decrease in HAM-D scores (CI: -13 to -21, p<0.001) and significant increases in erythrocyte levels of EPA (CI: +1.0% to +2.9%, p=0.001) and DHA (CI: +2.9% to +5.6%, p=0.007). DHA treatment was associated with a significant decrease in HAM-D scores (CI: -6 to -14, p<0.001) and a significant increase in DHA levels (CI: +0.2% to +2.3%, p=0.047), but not of EPA levels. The cPLA2 gene expression levels were significantly increased in patients received EPA (1.9 folds, p=0.038), but not DHA (1.08 folds, p=0.92). There was a tendency for both EPA and DHA groups to decrease COX-2 gene expressions. The gene expressions of COX-2, cPLA2, TPH-2 and 5-HTT did not differ between MDD cases and healthy controls. EPA differentiates from DHA in clinical antidepressant efficacy and in upregulating cPLA2 gene regulations, which supports the clinical observation showing the superiority of EPA's antidepressant effects. ClinicalTrials.gov identifier: NCT02615405. Copyright © 2017 Elsevier Inc. All rights reserved.

Intracellular gene transfer in action: Dual transcription and multiple silencings of nuclear and mitochondrial cox2 genes in legumes

PubMed Central

Adams, Keith L.; Song, Keming; Roessler, Philip G.; Nugent, Jacqueline M.; Doyle, Jane L.; Doyle, Jeff J.; Palmer, Jeffrey D.

1999-01-01

The respiratory gene cox2, normally present in the mitochondrion, was previously shown to have been functionally transferred to the nucleus during flowering plant evolution, possibly during the diversification of legumes. To search for novel intermediate stages in the process of intracellular gene transfer and to assess the evolutionary timing and frequency of cox2 transfer, activation, and inactivation, we examined nuclear and mitochondrial (mt) cox2 presence and expression in over 25 legume genera and mt cox2 presence in 392 genera. Transfer and activation of cox2 appear to have occurred during recent legume evolution, more recently than previously inferred. Many intermediate stages of the gene transfer process are represented by cox2 genes in the studied legumes. Nine legumes contain intact copies of both nuclear and mt cox2, although transcripts could not be detected for some of these genes. Both cox2 genes are transcribed in seven legumes that are phylogenetically interspersed with species displaying only nuclear or mt cox2 expression. Inactivation of cox2 in each genome has taken place multiple times and in a variety of ways, including loss of detectable transcripts or transcript editing and partial to complete gene loss. Phylogenetic evidence shows about the same number (3–5) of separate inactivations of nuclear and mt cox2, suggesting that there is no selective advantage for a mt vs. nuclear location of cox2 in plants. The current distribution of cox2 presence and expression between the nucleus and mitochondrion in the studied legumes is probably the result of chance mutations silencing either cox2 gene. PMID:10570164

Potential use of COX-2–aromatase inhibitor combinations in breast cancer

PubMed Central

Bundred, N J; Barnes, N L P

2005-01-01

Cyclooxygenase-2 (COX-2) is overexpressed in several epithelial tumours, including breast cancer. Cyclooxygenase-2-positive tumours tend to be larger, higher grade, node-positive and HER-2/neu-positive. High COX-2 expression is associated with poor prognosis. Cyclooxygenase-2 inhibition reduces the incidence of tumours in animal models, inhibits the development of invasive cancer in colorectal cancer and reduces the frequency of polyps in familial adenomatous polyposis (FAP). These effects may be as a result of increased apoptosis, reduced angiogenesis and/or proliferation. Studies of COX-2 inhibitors in breast cancer are underway both alone and in combination with other agents. There is evidence to suggest that combining COX-2 inhibitors with aromatase inhibitors, growth factor receptor blockers, or chemo- or radiotherapy may be particularly effective. Preliminary results from combination therapy with celecoxib and exemestane in postmenopausal women with advanced breast cancer showed that the combination increased the time to recurrence. Up to 80% of ductal carcinomas in situ (DCISs) express COX-2, therefore COX-2 inhibition may be of particular use in this situation. Cyclooxygenase-2 expression correlates strongly with expression of HER-2/neu. As aromatase inhibitors appear particularly effective in patients with HER-2/neu-positive tumours, the combination of aromatase inhibitors and COX-2 inhibitors may be particularly useful in both DCIS and invasive cancer. PMID:16100520

Increased expression of cyclooxygenase-2 protein during rat hepatocarcinogenesis caused by a choline-deficient, L-amino acid-defined diet and chemopreventive efficacy of a specific inhibitor, nimesulide.

PubMed

Denda, Ayumi; Kitayama, Wakashi; Murata, Akiko; Kishida, Hideki; Sasaki, Yasutaka; Kusuoka, Osamu; Tsujiuchi, Toshifumi; Tsutsumi, Masahiro; Nakae, Dai; Takagi, Hidetoshi; Konishi, Yoichi

2002-02-01

Expression of cyclooxygenase (COX)-2 protein during rat hepatocarcinogenesis associated with fatty change, fibrosis, cirrhosis and oxidative DNA damage, caused by a choline-deficient, L-amino acid-defined (CDAA) diet were investigated in F344 male rats, along with the chemopreventive efficacy of the specific COX-2 inhibitor, nimesulide (NIM). Nimesulide, which was administered in the diet at concentrations of 200, 400, 600 and 800 p.p.m. for 12 weeks, decreased the number and size of preneoplastic enzyme-altered liver foci, levels of oxidative DNA damage, and the grade and incidence of fibrosis in a dose-dependent manner. A preliminary long-term study of 65 weeks also revealed that 800 p.p.m. NIM decreased the multiplicity of neoplastic nodules and hepatocellular carcinomas and prevented the development of cirrhosis. Western blot analysis revealed that COX-2 protein was barely expressed in control livers and increased approximately 2.9-fold in the livers of rats fed on a CDAA diet for 12 weeks and approximately 4.5-5.4-fold in tumors, with a diameter larger than 5 mm, at 80 weeks. Immunohistochemically, COX-2 protein was positive in sinusoidal and stromal cells in fibrotic septa, which were identified by immunoelectron microscopy as Kupffer cells, macrophages, either activated Ito cells or fibroblasts, after exposure to the CDAA diet for 12 weeks, whereas it was only occasionally weakly positive in sinusoidal, probably Kupffer, cells in control livers. In neoplastic nodules in rats fed on a CDAA diet for 30 and 80 weeks, sinusoidal cells and cells with relatively large round nuclei and scanty cytoplasm were strongly positive for COX-2 protein, with the neoplastic hepatocytes in the minority of the nodules, but not the cancer cells, being moderately positive. These results clearly indicate that rat hepatocarcinogenesis, along with fatty change, fibrosis and cirrhosis, is associated with increased expression of COX-2 protein, and point to the chemopreventive efficacy of a selective COX-2 inhibitor against, at least, the early stages of hepatocarcinogenesis.

Adenosine up-regulates cyclooxygenase-2 in human granulocytes: impact on the balance of eicosanoid generation.

PubMed

Pouliot, Marc; Fiset, Marie-Elaine; Massé, Mireille; Naccache, Paul H; Borgeat, Pierre

2002-11-01

Polymorphonuclear neutrophils (granulocytes; PMNs) are often the first blood cells to migrate toward inflammatory lesions to perform host defense functions. PMNs respond to specific stimuli by releasing several factors and generate lipid mediators of inflammation from the 5-lipoxygenase and the inducible cyclooxygenase (COX)-2 pathways. In view of adenosine's anti-inflammatory properties and suppressive impact on the 5-lipoxygenase pathway, we addressed in this study the impact of this autacoid on the COX-2 pathway. We observed that adenosine up-regulates the expression of the COX-2 enzyme and mRNA. Production of PGE(2) in response to exogenous arachidonic acid was also increased by adenosine and correlated with COX-2 protein levels. The potentiating effect of adenosine on COX-2 could be mimicked by pharmacological increases of intracellular cAMP levels, involving the latter as a putative second messenger for the up-regulation of COX-2 by adenosine. Specific COX-2 inhibitors were used to confirm the predominant role of the COX-2 isoform in the formation of prostanoids by stimulated PMNs. Withdrawal of extracellular adenosine strikingly emphasized the inhibitory potential of PGE(2) on leukotriene B(4) formation and involved the EP(2) receptor subtype in this process. Thus, adenosine may promote a self-limiting regulatory process through the increase of PGE(2) generation, which may result in the inhibition of PMN functions. This study identifies a new aspect of the anti-inflammatory properties of adenosine in leukocytes, introducing the concept that this autacoid may exert its immunomodulatory activities in part by modifying the balance of lipid mediators generated by PMNs.

D-limonene suppresses doxorubicin-induced oxidative stress and inflammation via repression of COX-2, iNOS, and NFκB in kidneys of Wistar rats.

PubMed

Rehman, Muneeb U; Tahir, Mir; Khan, Abdul Quaiyoom; Khan, Rehan; Oday-O-Hamiza; Lateef, Abdul; Hassan, Syed Kazim; Rashid, Sumaya; Ali, Nemat; Zeeshan, Mirza; Sultana, Sarwat

2014-04-01

D-limonene is a naturally occurring monoterpene and has been found to posses numerous therapeutic properties. In this study, we used D-limonene as a protective agent against the nephrotoxic effects of anticancer drug doxorubicin (Dox). Rats were given D-limonene at doses of 5% and 10% mixed with diet for 20 consecutive days. Dox was give at the dose of 20 mg/kg body weight intraperitoneally. The protective effects of D-limonene on Dox-induced oxidative stress and inflammation were investigated by assaying oxidative stress biomarkers, lipid peroxidation, serum toxicity markers, proinflammatory cytokines, and expression of nuclear factor kappa B (NFκB), cyclo-oxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) and Nitrite levels. Administration of Dox (20 mg/kg body weight) in rats enhanced renal lipid peroxidation; depleted glutathione content and anti-oxidant enzymes; elevated levels of kidney toxicity markers viz. kidney injury molecule-1 (KIM-1), blood urea nitrogen (BUN), and creatinine; enhanced expression of NFκB, COX-2, and iNOS and nitric oxide. Treatment with D-limonene prevented oxidative stress by restoring the levels of antioxidant enzymes, further both doses of 5% and 10% showed significant decrease in inflammatory response. Both the doses of D-limonene significantly decreased the levels of kidney toxicity markers KIM-1, BUN, and creatinine. D-limonene also effectively decreased the Dox induced overexpression of NF-κB, COX-2, and iNOS and nitric oxide. Data from the present study indicate the protective role of D-limonene against Dox-induced renal damage.

Pirfenidone attenuates IL-1β-induced COX-2 and PGE2 production in orbital fibroblasts through suppression of NF-κB activity.

PubMed

Choi, Youn-Hee; Back, Keum Ok; Kim, Hee Ja; Lee, Sang Yeul; Kook, Koung Hoon

2013-08-01

The aim of this study was to determine the effect of pirfenidone on interleukin (IL)-1β-induced cyclooxygenase (COX)-2 and prostaglandin (PG)E2 expression in orbital fibroblasts from patients with thyroid-associated ophthalmopathy (TAO). Primary cultures of orbital fibroblasts from patients with TAO (n = 4) and non-TAO subjects (n = 4) were prepared. The level of PGE2 in orbital fibroblasts treated with IL-1β in the presence or absence of pirfenidone was measured using an enzyme-linked immunosorbent assay. The effect of pirfenidone on IL-1β-induced COX-2 expression in orbital fibroblasts from patients with TAO was evaluated by reverse transcription-polymerase chain reaction (PCR) and quantitative real-time PCR analyses, and verified by Western blot. Activation of nuclear factor-κB (NF-κB) was evaluated by immunoblotting for inhibitor of κB (IκB)α and phosphorylated IκBα, and DNA-binding activity of p50/p65 NF-κB was analyzed by electrophoretic mobility shift assay. In addition, IL-1 receptor type 1 (IL-1R1) expression was assessed by RT-PCR in IL-1β-treated cells with or without pirfenidone. Pirfenidone significantly attenuated IL-1β-induced PGE2 release in both TAO and non-TAO cells. IL-1β-induced COX-2 mRNA and protein expression decreased significantly following co-treatment with pirfenidone. IL-1β-induced IκBα phosphorylation and degradation decreased in the presence of pirfenidone and led to decreased nuclear translocation and DNA binding of the active NF-κB complex. In our system, neither IL-1β nor pirfenidone co-treatment influenced IL-1R1 expression. Our results suggest that pirfenidone attenuates the IL-1β-induced PGE2/COX-2 production in TAO orbital fibroblasts, which is related with suppression of the NF-κB activation. Copyright © 2013 Elsevier Ltd. All rights reserved.

FOXP3 inhibits cancer stem cell self-renewal via transcriptional repression of COX2 in colorectal cancer cells.

PubMed

Liu, Shuo; Zhang, Cun; Zhang, Kuo; Gao, Yuan; Wang, Zhaowei; Li, Xiaoju; Cheng, Guang; Wang, Shuning; Xue, Xiaochang; Li, Weina; Zhang, Wei; Zhang, Yingqi; Xing, Xianghui; Li, Meng; Hao, Qiang

2017-07-04

Colon cancer stem cell (cCSC) is considered as the seed cell of colon cancer initiation and metastasis. Cyclooxygenase-2 (COX2), a downstream target of NFκB, is found to be essential in promoting cancer stem cell renewal. However, how COX2 is dysregulated in cCSCs is largely unknown. In this study, we found that the expression of transcription factor FOXP3 was much lower in the spheroids than that in the parental tumor cells. Overexpression of FOXP3 significantly decreased the numbers of spheres, reduced the side population. Accordingly, FOXP3 expression decreased the tumor size and weight in the xenograft model. The tumor inhibitory effects of FOXP3 were rarely seen when COX2 was additionally knocked down. Mechanically, FOXP3 transcriptionally repressed COX2 expression via interacting with and thus inhibiting p65 activity on the putative NFκB response elements in COX2 promoter. Taken together, we here revealed possible involvement of FOXP3 in regulating cCSC self-renewal via tuning COX2 expression, and thus providing a new target for the eradication of colon cancer stem cells.

Cyclooxygenase-2 is an obligatory factor in methamphetamine-induced neurotoxicity.

PubMed

Thomas, David M; Kuhn, Donald M

2005-05-01

Methamphetamine causes persistent damage to dopamine nerve endings of the striatum. The mechanisms underlying its neurotoxicity are not fully understood, but considerable evidence points to oxidative stress as a probable mechanism. A recent microarray analysis of gene expression changes caused by methamphetamine revealed that cyclooxygenase-2 (COX-2) was induced along with its transcription factor CCAAT/enhancer-binding protein (Thomas DM, Francescutti-Verbeem DM, Liu X, and Kuhn DM, 2004). We report presently that methamphetamine increases striatal expression of COX-2 protein. Cyclooxygenase-1 (COX-1) expression was not changed. Mice bearing a null mutation of the gene for COX-2 were resistant to methamphetamine-induced neurotoxicity. COX-1 knockouts, like wild-type mice, showed extensive dopamine nerve terminal damage. Selective inhibitors of COX-1 [5-(4-chlorophenyl)-1-(4-methoxyphenyl)-3-trifluoromethyl pyrazole (SC-560)], COX-2 [N-[2-(cyclohexyloxy)-4-nitrophenyl] methanesulfonamide (NS-398), rofecoxib], or COX-3 (antipyrine) or a nonselective inhibitor of the COX-1/2 isoforms (ketoprofen) did not protect mice from neurotoxicity. Finally, methamphetamine did not change striatal prostaglandin E(2) content. Taken together, these data suggest that COX-2 is an obligatory factor in methamphetamine-induced neurotoxicity. The functional aspect of COX-2 that contributes to drug-induced neurotoxicity does not appear to be its prostaglandin synthetic capacity. Instead, the peroxidase activity associated with COX-2, which can lead to the formation of reactive oxygen species and dopamine quinones, can account for its role.

Anti-tumor effect and mechanism of cyclooxygenase-2 inhibitor through matrix metalloproteinase 14 pathway in PANC-1 cells.

PubMed

Li, Siyuan; Gu, Zhuoyu; Xiao, Zhiwei; Zhou, Ting; Li, Jun; Sun, Kan

2015-01-01

To investigate whether celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, can attenuate proliferation, migration, invasion and MMP-14 expression in pancreatic cancer cells PANC-1 and the possible anti-tumor mechanism of celecoxib. Human pancreatic cancer cell line PANC-1 cells were treated with diverse concentrations of celecoxib (20, 60, 100 μmol/L). Cell proliferation, invasion and migration capabilities were measured by MTT colorimetry, transwell invasion assay, and scratch assay separately. At the same time, the protein expression of COX-2 and MMP-14 was assessed by ELISA. The capabilities of proliferation, invasion and migration in PANC-1 cells were attenuated in a concentration-dependent manner after treated with celecoxib, followed by the down-regulation of the protein expression of COX-2 and MMP-14. In addition, MMP-14 expression was significantly positively correlated with COX-2 expression. COX-2 inhibitor celecoxib can inhibit the proliferation, invasion and migration of PANC-1 cells via down-regulating the expression of MMP-14 in a concentration-dependent manner, thus contributing to its anti-tumor effect in pancreatic cancer.

A Cross-Talk Between NFAT and NF-κB Pathways is Crucial for Nickel-Induced COX-2 Expression in Beas-2B Cells

PubMed Central

Cai, T.; Li, X.; Ding, J.; Luo, W.; Li, J.; Huang, C.

2013-01-01

Cyclooxygenase-2 (COX-2) is a critical enzyme implicated in chronic inflammation-associated cancer development. Our studies have shown that the exposure of Beas-2B cells, a human bronchial epithelial cell line, to lung carcinogenic nickel compounds results in increased COX-2 expression. However, the signaling pathways leading to nickel-induced COX-2 expression are not well understood. In the current study, we found that the exposure of Beas-2B cells to nickel compounds resulted in the activation of both nuclear factor of activated T cell (NFAT) and nuclear factor-κB (NF-κB). The expression of COX-2 induced upon nickel exposure was inhibited by either a NFAT pharmacological inhibitor or the knockdown of NFAT3 by specific siRNA. We further found that the activation of NFAT and NF-κB was dependent on each other. Since our previous studies have shown that NF-κB activation is critical for nickel-induced COX-2 expression in Beas-2B cells exposed to nickel compounds under same experimental condition, we anticipate that there might be a cross-talk between the activation of NFAT and NF-κB for the COX-2 induction due to nickel exposure in Beas-2B cells. Furthermore, we showed that the scavenging of reactive oxygen species (ROS) by introduction of mitochondrial catalase inhibited the activation of both NFAT and NF-κB, and the induction of COX-2 due to nickel exposure. Taken together, our results defining the evidence showing a key role of the cross-talk between NFAT and NF-κB pathways in regulating nickel-induced COX-2 expression, further provide insight into the understanding of the molecular mechanisms linking nickel exposure to its lung carcinogenic effects. PMID:21486220

Induction of cyclooxygenase-2 expression by prostaglandin E2 stimulation of the prostanoid EP4 receptor via coupling to Gαi and transactivation of the epidermal growth factor receptor in HCA-7 human colon cancer cells.

PubMed

Yoshida, Kenji; Fujino, Hiromichi; Otake, Sho; Seira, Naofumi; Regan, John W; Murayama, Toshihiko

2013-10-15

Increased expressions of cyclooxygenase-2 (COX-2) and its downstream metabolite, prostaglandin E2 (PGE2), are well documented events in the development of colorectal cancer. Interestingly, PGE2 itself can induce the expression of COX-2 thereby creating the potential for positive feedback. Although evidence for such a positive feedback has been previously described, the specific E-type prostanoid (EP) receptor subtype that mediates this response, as well as the relevant signaling pathways, remain unclear. We now report that the PGE2 stimulated induction of COX-2 expression in human colon cancer HCA-7 cells is mediated by activation of the prostanoid EP4 receptor subtype and is followed by coupling of the receptor to Gαi and the activation of phosphatidylinositol 3-kinase. Subsequent activation of metalloproteinases releases membrane bound heparin-binding epidermal growth factor-like growth factor resulting in the transactivation of epidermal growth factor receptors and the activation of the extracellular signal-regulated kinases and induction of COX-2 expression. This induction of COX-2 expression by PGE2 stimulation of the prostanoid EP4 receptor may underlie the upregulation of COX-2 during colorectal cancer and appears to be an early event in the process of tumorigenesis. © 2013 Elsevier B.V. All rights reserved.

Low-level laser therapy (LLLT; 780 nm) acts differently on mRNA expression of anti- and pro-inflammatory mediators in an experimental model of collagenase-induced tendinitis in rat.

PubMed

Pires, Débora; Xavier, Murilo; Araújo, Tiago; Silva, José Antônio; Aimbire, Flavio; Albertini, Regiane

2011-01-01

Low-level laser therapy (LLLT) has been found to produce anti-inflammatory effects in a variety of disorders. Tendinopathies are directly related to unbalance in expression of pro- and anti-inflammatory cytokines which are responsible by degeneration process of tendinocytes. In the current study, we decided to investigate if LLLT could reduce mRNA expression for TNF-α, IL-1β, IL-6, TGF-β cytokines, and COX-2 enzyme. Forty-two male Wistar rats were divided randomly in seven groups, and tendinitis was induced with a collagenase intratendinea injection. The mRNA expression was evaluated by real-time PCR in 7th and 14th days after tendinitis. LLLT irradiation with wavelength of 780 nm required for 75 s with a dose of 7.7 J/cm(2) was administered in distinct moments: 12 h and 7 days post tendinitis. At the 12 h after tendinitis, the animals were irradiated once in intercalate days until the 7th or 14th day in and them the animals were killed, respectively. In other series, 7 days after tendinitis, the animals were irradiated once in intercalated days until the 14th day and then the animals were killed. LLLT in both acute and chronic phases decreased IL-6, COX-2, and TGF-β expression after tendinitis, respectively, when compared to tendinitis groups: IL-6, COX-2, and TGF-β. The LLLT not altered IL-1β expression in any time, but reduced the TNF-α expression; however, only at chronic phase. We conclude that LLLT administered with this protocol reduces one of features of tendinopathies that is mRNA expression for pro-inflammatory mediators.

Gene Therapy With Inducible Nitric Oxide Synthase Protects Against Myocardial Infarction via a Cyclooxygenase-2—Dependent Mechanism

PubMed Central

Li, Qianhong; Guo, Yiru; Xuan, Yu-Ting; Lowenstein, Charles J.; Stevenson, Susan C.; Prabhu, Sumanth D.; Wu, Wen-Jian; Zhu, Yanqing; Bolli, Roberto

2013-01-01

Although the inducible isoform of NO synthase (iNOS) mediates late preconditioning (PC), it is unknown whether iNOS gene transfer can replicate the cardioprotective effects of late PC, and the role of this protein in myocardial ischemia is controversial. Thus, the cDNA for human iNOS was cloned behind the Rous sarcoma virus (RSV) promoter to create adenovirus (Ad) 5/iNOS lacking E1, E2a, and E3 regions. Intramyocardial injection of Ad5/iNOS in mice increased local iNOS protein expression and activity and markedly reduced infarct size. The infarct-sparing effects of Ad5/iNOS were at least as powerful as those of ischemic PC. The increased iNOS expression was associated with increased cyclooxygenase-2 (COX-2) protein expression and prostanoid levels. Pretreatment with the COX-2–selective inhibitor NS-398 completely abrogated the infarct-sparing actions of Ad5/iNOS, demonstrating that COX-2 is an obligatory downstream effector of iNOS-dependent cardioprotection. We conclude that gene transfer of iNOS (an enzyme commonly thought to be detrimental) affords powerful cardioprotection the magnitude of which is equivalent to that of late PC. This is the first report that upregulation of iNOS, in itself, is sufficient to reduce infarct size. The results provide proof-of-principle for gene therapy against ischemia/reperfusion injury, which increases local myocardial NO synthase levels without the need for continuous intravenous infusion of NO donors and without altering systemic hemodynamics. The data also reveal the existence of a close coupling between iNOS and COX-2, whereby induction of the former enzyme leads to secondary induction of the latter, which in turn mediates the cytoprotective effects of iNOS. We propose that iNOS and COX-2 form a stress-responsive functional module that mitigates ischemia/reperfusion injury. PMID:12702642

Chronic inhibition of nitric-oxide synthase potentiates endothelium-dependent contractions in the rat aorta by augmenting the expression of cyclooxygenase-2.

PubMed

Qu, Chen; Leung, Susan W S; Vanhoutte, Paul M; Man, Ricky Y K

2010-08-01

Acute inhibition of nitric-oxide synthase (NOS) unmasks the release of endothelium-derived contracting factors (EDCFs). The present study investigated whether chronic inhibition of NOS modulates endothelium-dependent contractions. Eighteen-week-old male Sprague-Dawley rats were treated by daily gavage for 6 weeks with the NOS inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME) (60 mg/kg) or vehicle (distilled water; 1 ml/kg). Chronic treatment with L-NAME increased arterial blood pressure. Isometric tension was measured in aortic rings with or without endothelium. Endothelium-dependent relaxations to acetylcholine and the calcium ionophore 5-(methylamino)-2-[(2R,3R,6S,8S,9R,11R)-3,9,11-trimethyl-8-[(1S)-1-methyl-2-oxo-2-(1H-pyrrol-2-yl)-ethyl]-1,7-dioxaspiro[5.5]undec-2-yl]methyl]-4-benzoxazolecarboxylic acid (A23187) were reduced in preparations from L-NAME-treated rats. The reduction in relaxation to A23187 was partially reversed by L-arginine (1 mM). In quiescent aortic rings, A23187 caused contractions in the presence of L-NAME and intact endothelium. The A23187-induced contractions were greater in rings from the L-NAME-treated rats than in those from the control group. These contractions were abolished by the cyclooxygenase (COX)-2 inhibitor N-[2-cyclohexyloxy-4-nitrophenyl]methanesulfonamide (NS-398) and the thromboxane-prostanoid (TP) receptor antagonist 3-((6R)-6-{[(4-chlorophenyl)sulfonyl]amido}-2-methyl-5,6,7,8-tetrahydronaphthalen-1-yl)propanoate (S18886), but not by the COX-1 inhibitor 5-(4-chlorophenyl)-1-(4-methoxyphenyl)-3-(trifluoromethyl)-1H-pyrazole (SC-560). Chronic L-NAME treatment reduced the level of nitric oxide in the plasma but increased COX activity in the aortic rings. Western blotting and immunohistochemical staining showed that endothelial NOS expression was reduced in the aortae of the chronic L-NAME-treated group. COX-1 expression was augmented slightly, whereas COX-2 expression was up-regulated markedly. The TP receptor expression was comparable with control. These experiments demonstrate that chronic NOS inhibition increases endothelium-dependent contractions of the rat aorta by inducing COX-2 expression and augmenting the production of EDCF.

Serotonin and histamine mediate gastroprotective effect of fluoxetine against experimentally-induced ulcers in rats.

PubMed

Salem Sokar, Samia; Elsayed Elsayad, Mageda; Sabri Ali, Hend

2016-09-01

Research in the treatment of gastric ulcer has involved the investigation of new alternatives, such as anti-depressant drugs. The present study was designed to investigate the gastroprotective effects of fluoxetine against indomethacin and alcohol induced gastric ulcers in rats and the potential mechanisms of that effect. Fluoxetine (20 mg/kg) was administered IP for 14 days. For comparative purposes, other rats were treated with ranitidine (30 mg/kg). Thereafter, after 24 h of fasting, INDO (100 mg/kg) or absolute alcohol (5 ml/kg) was administered to all rats (saline was administered to naïve controls) and rats in each group were sacrificed 5 h (for INDO rats) or 1 h (for alcohol rats) later. Macroscopic examination revealed that both fluoxetine and ranitidine decreased ulcer scores in variable ratios, which was supported by microscopic histopathological examination. Biochemical analysis of fluoxetine- or ranitidine-pre-treated host tissues demonstrated reductions in tumor necrosis factor (TNF)-α and myeloperoxidase (MPO) levels and concomitant increases in gastric pH, nitric oxide (NO) and reduced glutathione (GSH) contents. Fluoxetine, more than ranitidine, also resulted in serotonin and histamine levels nearest to control values. Moreover, immuno-histochemical analysis showed that fluoxetine markedly enhanced expression of cyclo-oxygenases COX-1 and COX-2 in both models; in comparison, ranitidine did not affect COX-1 expression in either ulcer model but caused moderate increases in COX-2 expression in INDO-induced hosts and high expression in alcohol-induced hosts. The results here indicated fluoxetine exhibited better gastroprotective effects than ranitidine and this could be due to anti-secretory, anti-oxidant, anti-inflammatory and anti-histaminic effects of the drug, as well as a stabilization of gastric serotonin levels.

Picfeltarraenin IA inhibits lipopolysaccharide-induced inflammatory cytokine production by the nuclear factor-κB pathway in human pulmonary epithelial A549 cells.

PubMed

Shi, Rong; Wang, Qing; Ouyang, Yang; Wang, Qian; Xiong, Xudong

2016-02-01

The present study aimed to investigate the effect of picfeltarraenin IA (IA) on respiratory inflammation by analyzing its effect on interleukin (IL)-8 and prostaglandin E2 (PGE2) production. The expression of cyclooxygenase 2 (COX2) in human pulmonary adenocarcinoma epithelial A549 cells in culture was also examined. Human pulmonary epithelial A549 cells and the human monocytic leukemia THP-1 cell line were used in the current study. Cell viability was measured using a methylthiazol tetrazolium assay. The production of IL-8 and PGE2 was investigated using an enzyme-linked immunosorbent assay. The expression of COX2 and nuclear factor-κB (NF-κB)-p65 was examined using western blot analysis. Treatment with lipopolysaccharide (LPS; 10 µg/ml) resulted in the increased production of IL-8 and PGE2, and the increased expression of COX2 in the A549 cells. Furthermore, IA (0.1-10 µmol/l) significantly inhibited PGE2 production and COX2 expression in cells with LPS-induced IL-8, in a concentration-dependent manner. The results suggested that IA downregulates LPS-induced COX2 expression, and inhibits IL-8 and PGE2 production in pulmonary epithelial cells. Additionally, IA was observed to suppress the expression of COX2 in THP-1 cells, and also to regulate the expression of COX2 via the NF-κB pathway in the A549 cells, but not in the THP-1 cells. These results indicate that IA regulates LPS-induced cytokine release in A549 cells via the NF-κB pathway.

In vitro exposure to isoprene-derived secondary organic aerosol by direct deposition and its effects on COX-2 and IL-8 gene expression

NASA Astrophysics Data System (ADS)

Arashiro, Maiko; Lin, Ying-Hsuan; Sexton, Kenneth G.; Zhang, Zhenfa; Jaspers, Ilona; Fry, Rebecca C.; Vizuete, William G.; Gold, Avram; Surratt, Jason D.

2016-11-01

Atmospheric oxidation of isoprene, the most abundant non-methane hydrocarbon emitted into Earth's atmosphere primarily from terrestrial vegetation, is now recognized as a major contributor to the global secondary organic aerosol (SOA) burden. Anthropogenic pollutants significantly enhance isoprene SOA formation through acid-catalyzed heterogeneous chemistry of epoxide products. Since isoprene SOA formation as a source of fine aerosol is a relatively recent discovery, research is lacking on evaluating its potential adverse effects on human health. The objective of this study was to examine the effect of isoprene-derived SOA on inflammation-associated gene expression in human lung cells using a direct deposition exposure method. We assessed altered expression of inflammation-related genes in human bronchial epithelial cells (BEAS-2B) exposed to isoprene-derived SOA generated in an outdoor chamber facility. Measurements of gene expression of known inflammatory biomarkers interleukin 8 (IL-8) and cyclooxygenase 2 (COX-2) in exposed cells, together with complementary chemical measurements, showed that a dose of 0.067 µg cm-2 of SOA from isoprene photooxidation leads to statistically significant increases in IL-8 and COX-2 mRNA levels. Resuspension exposures using aerosol filter extracts corroborated these findings, supporting the conclusion that isoprene-derived SOA constituents induce the observed changes in mRNA levels. The present study is an attempt to examine the early biological responses of isoprene SOA exposure in human lung cells.

Compensatory Hypertrophy Induced by Ventricular Cardiomyocyte Specific COX-2 Expression in Mice

PubMed Central

Streicher, John M.; Kamei, Kenichiro; Ishikawa, Tomo-o; Herschman, Harvey; Wang, Yibin

2010-01-01

Cyclooxygenase-2 (COX-2) is an important mediator of inflammation in stress and disease states. Recent attention has focused on the role of COX-2 in human heart failure and diseases, due to the finding that highly specific COX-2 inhibitors (i.e. Vioxx) increased the risk of myocardial infarction and stroke in chronic users. However, the specific impact of COX-2 expression in the intact heart remains to be determined. We report here the development of a transgenic mouse model, using a loxP-Cre approach, that displays robust COX-2 overexpression and subsequent prostaglandin synthesis specifically in ventricular myocytes. Histological, functional and molecular analyses showed that ventricular myocyte specific COX-2 overexpression led to cardiac hypertrophy and fetal gene marker activation, but with preserved cardiac function. Therefore, specific induction of COX-2 and prostaglandin in vivo is sufficient to induce compensated hypertrophy and molecular remodeling. PMID:20170663

Hexavalent Chromium Cr(VI) Up-Regulates COX-2 Expression through an NFκB/c-Jun/AP-1–Dependent Pathway

PubMed Central

Zuo, Zhenghong; Cai, Tongjian; Li, Jingxia; Zhang, Dongyun; Yu, Yonghui

2012-01-01

Background: Hexavalent chromium [Cr(VI)] is recognized as a human carcinogen via inhalation. However, the molecular mechanisms by which Cr(VI) causes cancers are not well understood. Objectives: We evaluated cyclooxygenase-2 (COX-2) expression and the signaling pathway leading to this induction due to Cr(VI) exposure in cultured cells. Methods: We used the luciferase reporter assay and Western blotting to determine COX-2 induction by Cr(VI). We used dominant negative mutant, genetic knockout, gene knockdown, and chromatin immunoprecipitation approaches to elucidate the signaling pathway leading to COX-2 induction. Results: We found that Cr(VI) exposure induced COX-2 expression in both normal human bronchial epithelial cells and mouse embryonic fibroblasts in a concentration- and time-dependent manner. Deletion of IKKβ [inhibitor of transcription factor NFκB (IκB) kinase β; an upstream kinase responsible for nuclear factor κB (NFκB) activation] or overexpression of TAM67 (a dominant-negative mutant of c-Jun) dramatically inhibited the COX-2 induction due to Cr(VI), suggesting that both NFκB and c-Jun/AP-1 pathways were required for Cr(VI)-induced COX-2 expression. Our results show that p65 and c-Jun are two major components involved in NFκB and AP-1 activation, respectively. Moreover, our studies suggest crosstalk between NFκB and c-Jun/AP-1 pathways in cellular response to Cr(VI) exposure for COX-2 induction. Conclusion: We demonstrate for the first time that Cr(VI) is able to induce COX-2 expression via an NFκB/c-Jun/AP-1–dependent pathway. Our results provide novel insight into the molecular mechanisms linking Cr(VI) exposure to lung inflammation and carcinogenesis. PMID:22472290

Gentiolactone, a Secoiridoid Dilactone from Gentiana triflora, Inhibits TNF-α, iNOS and Cox-2 mRNA Expression and Blocks NF-κB Promoter Activity in Murine Macrophages

PubMed Central

Yamada, Hidetoshi; Kikuchi, Sayaka; Inui, Tomoki; Takahashi, Hideyuki; Kimura, Ken-ichi

2014-01-01

Background Gentian roots have been used as a herbal medicine because of their anti-inflammatory activities. However, the molecular mechanisms of these anti-inflammatory effects remain to be completely explained. Methods and Findings Here, we investigated anti-inflammatory effects of gentian roots and showed that root extracts from Gentiana triflora inhibited lipopolysaccharide (LPS)-induced expression of TNF-α in RAW264.7 cells. The extracts also contained swertiamarin and gentiopicroside, which are the major active compounds of gentian roots; however, neither compound had any effect on LPS-induced TNF-α production in our test system. We isolated gentiolactone as an inhibitor of TNF-α production from the extracts. Gentiolactone also inhibited LPS-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (Cox-2) expression at the mRNA level. Moreover, gentiolactone suppressed NF-κB transcriptional activity without inhibition of IκB degradation or NF-κB nuclear transport. Conclusions Our results indicate that inhibition of TNF-α, iNOS and Cox-2 expression by gentiolactone is one of the mechanisms of the anti-inflammatory properties of gentian roots. PMID:25423092

Inflammation in gastric cancer: Interplay of the COX-2/prostaglandin E2 and Toll-like receptor/MyD88 pathways.

PubMed

Echizen, Kanae; Hirose, Osamu; Maeda, Yusuke; Oshima, Masanobu

2016-04-01

Cyclooxygenase-2 (COX-2) and its downstream product prostaglandin E2 (PGE2 ) play a key role in generation of the inflammatory microenvironment in tumor tissues. Gastric cancer is closely associated with Helicobacter pylori infection, which stimulates innate immune responses through Toll-like receptors (TLRs), inducing COX-2/PGE2 pathway through nuclear factor-κB activation. A pathway analysis of human gastric cancer shows that both the COX-2 pathway and Wnt/β-catenin signaling are significantly activated in tubular-type gastric cancer, and basal levels of these pathways are also increased in other types of gastric cancer. Expression of interleukin-11, chemokine (C-X-C motif) ligand 1 (CXCL1), CXCL2, and CXCL5, which play tumor-promoting roles through a variety of mechanisms, is induced in a COX-2/PGE2 pathway-dependent manner in both human and mouse gastric tumors. Moreover, the COX-2/PGE2 pathway plays an important role in the maintenance of stemness with expression of stem cell markers, including CD44, Prom1, and Sox9, which are induced in both gastritis and gastric tumors through a COX-2/PGE2 -dependent mechanism. In contrast, disruption of Myd88 results in suppression of the inflammatory microenvironment in gastric tumors even when the COX-2/PGE2 pathway is activated, indicating that the interplay of the COX-2/PGE2 and TLR/MyD88 pathways is needed for inflammatory response in tumor tissues. Furthermore, TLR2/MyD88 signaling plays a role in maintenance of stemness in normal stem cells as well as gastric tumor cells. Accordingly, these results suggest that targeting the COX-2/PGE2 pathway together with TLR/MyD88 signaling, which would suppress the inflammatory microenvironment and maintenance of stemness, could be an effective preventive or therapeutic strategy for gastric cancer. © 2016 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

HCV NS5A Up-Regulates COX-2 Expression via IL-8-Mediated Activation of the ERK/JNK MAPK Pathway

PubMed Central

Chen, Wei-Chun; Tseng, Chin-Kai; Chen, Yen-Hsu; Lin, Chun-Kuang; Hsu, Shih-hsien; Wang, Shen-Nien; Lee, Jin-Ching

2015-01-01

Chronic hepatitis C virus (HCV) infection leads to intrahepatic inflammation and liver cell injury, which are considered a risk factor for virus-associated hepatitis, cirrhosis, and hepatocellular carcinoma worldwide. Inflammatory cytokines are critical components of the immune system and influence cellular signaling, and genetic imbalances. In this study, we found that cyclooxygenase-2 (COX-2) and interleukin-8 (IL-8) were significantly induced by HCV infection and HCV NS5A expression, and induction of COX-2 correlated with HCV-induced IL-8 production. We also found that the ERK and JNK signaling pathways were involved in the regulation of IL-8-mediated COX-2 induction in response to HCV infection. Using a promoter-linked reporter assay, we identified that the C/EBP regulatory element within the COX-2 promoter was the dominant factor responsible for the induction of COX-2 by HCV. Silencing C/EBP attenuated HCV-induced COX-2 expression. Our results revealed that HCV-induced inflammation promotes viral replication, providing new insights into the involvement of IL-8-mediated COX-2 induction in HCV replication. PMID:26231035

Contribution of vasoactive eicosanoids and nitric oxide production to the effect of selective cyclooxygenase-2 inhibitor, NS-398, on endotoxin-induced hypotension in rats.

PubMed

Tunctan, Bahar; Korkmaz, Belma; Cuez, Tuba; Kemal Buharalioglu, C; Sahan-Firat, Seyhan; Falck, John; Malik, Kafait U

2010-11-01

Our previous studies with the use of non-selective cyclooxygenase (COX) inhibitor, indomethacin, demonstrated that prostanoids produced during endotoxaemia increase inducible nitric oxide synthase (iNOS) protein expression and nitric oxide synthesis, and decrease cyctochrome P450 (CYP) 4A1 protein expression and CYP 4A activity. The results suggest that dual inhibition of iNOS and COX by indomethacin restores blood pressure presumably due to increased production of 20-hydroxyeicosatetraenoic acid (20-HETE) derived from CYP 4A in endotoxaemic rats. The present study examined whether increased levels of vasoconstrictor eicosanoids, 20-HETE, prostaglandin F(2α) (PGF(2α) )and thromboxane A(2) (TxA(2) ), would contribute to the effect of selective COX-2 inhibition to prevent endotoxin (ET)-induced fall in blood pressure associated with an increase in the production of vasodilator prostanoids, prostaglandin I(2) (PGI(2) ) and prostaglandin E(2) (PGE(2) ) and nitric oxide synthesis. Mean arterial blood pressure fell by 31 mmHg and heart rate (HR) rose by 90 beats/min. in male Wistar rats treated with ET (10 mg/kg, i.p.). The fall in mean arterial pressure and increase in HR were associated with increased levels of 6-keto-prostaglandin F(1α) (6-keto-PGF(1α) ), PGE(2) , TxB(2) , and nitrite in the serum, kidney, heart, thoracic aorta and/or superior mesenteric artery. Systemic and renal 20-HETE and PGF(2α) levels were also decreased in endotoxaemic rats. These effects of ET were prevented by a selective COX-2 inhibitor, N-(2-cyclohexyloxy-4-nitrophenyl)methansulphonamide (10 mg/kg, i.p.), given 1 hr after injection of ET. These data suggest that an increase in 20-HETE and PGF(2α) levels associated with decreased production of PGI(2) , PGE(2) , and TxA(2) , and nitric oxide synthesis contributes to the effect of selective COX-2 inhibitor to prevent the hypotension during rat endotoxaemia. © 2010 The Authors. Basic & Clinical Pharmacology & Toxicology © 2010 Nordic Pharmacological Society.

Pathogenesis of NSAID-induced gastric damage: Importance of cyclooxygenase inhibition and gastric hypermotility

PubMed Central

Takeuchi, Koji

2012-01-01

This article reviews the pathogenic mechanism of non-steroidal anti-inflammatory drug (NSAID)-induced gastric damage, focusing on the relation between cyclooxygenase (COX) inhibition and various functional events. NSAIDs, such as indomethacin, at a dose that inhibits prostaglandin (PG) production, enhance gastric motility, resulting in an increase in mucosal permeability, neutrophil infiltration and oxyradical production, and eventually producing gastric lesions. These lesions are prevented by pretreatment with PGE2 and antisecretory drugs, and also via an atropine-sensitive mechanism, not related to antisecretory action. Although neither rofecoxib (a selective COX-2 inhibitor) nor SC-560 (a selective COX-1 inhibitor) alone damages the stomach, the combined administration of these drugs provokes gastric lesions. SC-560, but not rofecoxib, decreases prostaglandin E2 (PGE2) production and causes gastric hypermotility and an increase in mucosal permeability. COX-2 mRNA is expressed in the stomach after administration of indomethacin and SC-560 but not rofecoxib. The up-regulation of indomethacin-induced COX-2 expression is prevented by atropine at a dose that inhibits gastric hypermotility. In addition, selective COX-2 inhibitors have deleterious influences on the stomach when COX-2 is overexpressed under various conditions, including adrenalectomy, arthritis, and Helicobacter pylori-infection. In summary, gastric hypermotility plays a primary role in the pathogenesis of NSAID-induced gastric damage, and the response, causally related with PG deficiency due to COX-1 inhibition, occurs prior to other pathogenic events such as increased mucosal permeability; and the ulcerogenic properties of NSAIDs require the inhibition of both COX-1 and COX-2, the inhibition of COX-1 upregulates COX-2 expression in association with gastric hypermotility, and PGs produced by COX-2 counteract the deleterious effect of COX-1 inhibition. PMID:22611307

Phloretin Inhibits Phorbol Ester–Induced Tumor Promotion and Expression of Cyclooxygenase-2 in Mouse Skin: Extracellular Signal-Regulated Kinase and Nuclear Factor-κB as Potential Targets

PubMed Central

Shin, Jun-Wan; Kundu, Joydeb Kumar

2012-01-01

Abstract The present study investigated the effect of phloretin [2′,4′,6′-trihydroxy-3-(4-hydroxyphenyl)-propiophenone] on 12-O-tetradecanoylphorbol 13-acetate (TPA)–induced cyclooxygenase-2 (COX-2) expression and tumor promotion in mouse skin and explored the underlying molecular mechanisms. Topical application of phloretin significantly inhibited 7,12-dimethylbenz[a]anthracene-initiated and TPA-promoted mouse skin carcinogenesis. Pretreatment with phloretin on the dorsal skin of mice inhibited TPA-induced COX-2 expression in a dose-dependent manner. To elucidate the molecular mechanism underlying COX-2 inhibition by phloretin, we examined its effect on TPA-induced activation of nuclear factor-κB (NF-κB), a ubiquitous transcription factor responsible for TPA-induced COX-2 expression in mouse skin. Topically applied phloretin decreased the TPA-induced DNA binding of NF-κB. In addition, phloretin inhibited the phosphorylation as well as the catalytic activity of extracellular signal-regulated kinase (ERK), which was previously found to activate NF-κB and induce COX-2 expression in TPA-treated mouse skin. Taken together, the inhibitory effects of phloretin on TPA-induced NF-κB activation and COX-2 expression through the modulation of ERK signaling may partly account for its antitumor-promoting effect on mouse skin carcinogenesis. PMID:22181070

Phloretin inhibits phorbol ester-induced tumor promotion and expression of cyclooxygenase-2 in mouse skin: extracellular signal-regulated kinase and nuclear factor-κB as potential targets.

PubMed

Shin, Jun-Wan; Kundu, Joydeb Kumar; Surh, Young-Joon

2012-03-01

The present study investigated the effect of phloretin [2',4',6'-trihydroxy-3-(4-hydroxyphenyl)-propiophenone] on 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced cyclooxygenase-2 (COX-2) expression and tumor promotion in mouse skin and explored the underlying molecular mechanisms. Topical application of phloretin significantly inhibited 7,12-dimethylbenz[a]anthracene-initiated and TPA-promoted mouse skin carcinogenesis. Pretreatment with phloretin on the dorsal skin of mice inhibited TPA-induced COX-2 expression in a dose-dependent manner. To elucidate the molecular mechanism underlying COX-2 inhibition by phloretin, we examined its effect on TPA-induced activation of nuclear factor-κB (NF-κB), a ubiquitous transcription factor responsible for TPA-induced COX-2 expression in mouse skin. Topically applied phloretin decreased the TPA-induced DNA binding of NF-κB. In addition, phloretin inhibited the phosphorylation as well as the catalytic activity of extracellular signal-regulated kinase (ERK), which was previously found to activate NF-κB and induce COX-2 expression in TPA-treated mouse skin. Taken together, the inhibitory effects of phloretin on TPA-induced NF-κB activation and COX-2 expression through the modulation of ERK signaling may partly account for its antitumor-promoting effect on mouse skin carcinogenesis.

Effects of Camphorquinone on Cytotoxicity, Cell Cycle Regulation and Prostaglandin E2 Production of Dental Pulp Cells: Role of ROS, ATM/Chk2, MEK/ERK and Hemeoxygenase-1

PubMed Central

Chang, Mei-Chi; Lin, Li-Deh; Wu, Min-Tsz; Chan, Chiu-Po; Chang, Hsiao-Hua; Lee, Ming-Shu; Sun, Tzu-Ying; Jeng, Po-Yuan; Yeung, Sin-Yuet; Lin, Hsueh-Jen; Jeng, Jiiang-Huei

2015-01-01

Camphorquinone (CQ) is a popularly-used photosensitizer in composite resin restoration. In this study, the effects of CQ on cytotoxicity and inflammation-related genes and proteins expression of pulp cells were investigated. The role of reactive oxygen species (ROS), ATM/Chk2/p53 and hemeoxygenase-1 (HO-1) and MEK/ERK signaling was also evaluated. We found that ROS and free radicals may play important role in CQ toxicity. CQ (1 and 2 mM) decreased the viability of pulp cells to about 70% and 50% of control, respectively. CQ also induced G2/M cell cycle arrest and apoptosis of pulp cells. The expression of type I collagen, cdc2, cyclin B, and cdc25C was inhibited, while p21, HO-1 and cyclooxygenase-2 (COX-2) were stimulated by CQ. CQ also activated ATM, Chk2, and p53 phosphorylation and GADD45α expression. Besides, exposure to CQ increased cellular ROS level and 8-isoprostane production. CQ also stimulated COX-2 expression and PGE2 production of pulp cells. The reduction of cell viability caused by CQ can be attenuated by N-acetyl-L-cysteine (NAC), catalase and superoxide dismutase (SOD), but can be promoted by Zinc protoporphyin (ZnPP). CQ stimulated ERK1/2 phosphorylation, and U0126 prevented the CQ-induced COX-2 expression and prostaglandin E2 (PGE2) production. These results indicate that CQ may cause cytotoxicity, cell cycle arrest, apoptosis, and PGE2 production of pulp cells. These events could be due to stimulation of ROS and 8-isoprostane production, ATM/Chk2/p53 signaling, HO-1, COX-2 and p21 expression, as well as the inhibition of cdc2, cdc25C and cyclin B1. These results are important for understanding the role of ROS in pathogenesis of pulp necrosis and pulpal inflammation after clinical composite resin filling. PMID:26658076

Nicotine enhances skin necrosis and expression of inflammatory mediators in a rat pressure ulcer model.

PubMed

Tsutakawa, S; Kobayashi, D; Kusama, M; Moriya, T; Nakahata, N

2009-11-01

Many bedridden patients develop pressure ulcers, not only in hospital but also at home. Clinical studies have indicated cigarette smoking to be a risk factor for pressure ulcers. However, the contribution of nicotine to pressure ulcer formation has not been identified. We aimed to clarify the effect of nicotine on pressure ulcer formation, and its mechanism. Ischaemia-reperfusion (I/R) was performed in rat dorsal skin to induce pressure ulcers. The extent of the resulting necrotic area was determined. To clarify the mechanism of the effect of nicotine, mRNA levels of cyclooxygenase-2 (COX-2), interleukin (IL)-1beta, IL-6 and inducible nitric oxide synthase (iNOS) and protein expression of COX-2 and iNOS in the necrotic area were investigated by real-time reverse transcription-polymerase chain reaction and Western blotting, respectively. Furthermore, the effects of the COX-2 inhibitor NS-398 and the iNOS inhibitor aminoguanidine on necrosis were examined. Skin necrosis in the I/R-treated area was significantly increased by intraperitoneal administration of nicotine (0.175 mg kg(-1) daily). Repeated nicotine administration had little effect on systolic and diastolic blood pressure. I/R treatment increased mRNA levels of COX-2, IL-1beta, IL-6 and iNOS, which were further augmented by nicotine in a dose-dependent manner. Correspondingly, nicotine (0.35 mg kg(-1) daily) markedly enhanced the protein expression of COX-2 and iNOS. Moreover, NS-398 and aminoguanidine showed a tendency to abrogate the increase of I/R-induced skin necrosis caused by nicotine. These results suggest that the increased risk of pressure ulcers due to cigarette smoking is mediated, in part, by nicotine. They also indicated that the effect of nicotine is not mediated by a change in blood pressure, but is elicited via an increase of inflammatory mediators in the I/R-treated skin.

Amelioration of meconium-induced acute lung injury by parecoxib in a rabbit model

PubMed Central

Li, Ai-Min; Zhang, Li-Na; Li, Wen-Zhi

2015-01-01

Cyclooxygenase-2 (COX-2) plays important roles in various inflammatory conditions and is significantly increased in meconium-induced lung injury. We investigated the effects of parecoxib on meconium-induced acute lung injury (ALI) in rabbits. Twenty-four rabbits were randomized into sham, control, and parecoxib groups. Rabbits in the control and parecoxib groups underwent tracheal instillation of meconium, followed by intravenous injection of saline or parecoxib and 4 h of ventilation. The airway pressure, dynamic compliance, and ratio of partial pressure of oxygen in arterial blood to fraction of inspired oxygen (PaO2/FiO2 ratio) were recorded at baseline (T0) and 4 h after instillation (T1-T4). The lung tissue wet-to-dry weight ratio; neutrophil percentage; and total protein, tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-8, prostaglandin E2, and malondialdehyde levels in bronchoalveolar lavage fluid (BALF) were evaluated. The myeloperoxidase activity, COX-2 expression, and degree of histopathologic injury in lung tissue were also analyzed. The airway pressure, compliance, and PaO2/FiO2 ratio were significantly improved by parecoxib after meconium instillation. The lung wet-to-dry weight ratio, total protein level, and neutrophil percentage in BALF were lowest in the parecoxib group. The TNF-α, IL-1β, IL-8, prostaglandin E2, and malondialdehyde levels in the BALF were lowest in the parecoxib group. The COX-2 expression and myeloperoxidase activity in lung tissue were significantly reduced by parecoxib. The degree of lung injury was also reduced. In conclusions: Parecoxib effectively ameliorates respiratory function and attenuates meconium-induced ALI. These effects are correlated with prostaglandin E2 and COX-2 inhibition. PMID:26221218

Amelioration of meconium-induced acute lung injury by parecoxib in a rabbit model.

PubMed

Li, Ai-Min; Zhang, Li-Na; Li, Wen-Zhi

2015-01-01

Cyclooxygenase-2 (COX-2) plays important roles in various inflammatory conditions and is significantly increased in meconium-induced lung injury. We investigated the effects of parecoxib on meconium-induced acute lung injury (ALI) in rabbits. Twenty-four rabbits were randomized into sham, control, and parecoxib groups. Rabbits in the control and parecoxib groups underwent tracheal instillation of meconium, followed by intravenous injection of saline or parecoxib and 4 h of ventilation. The airway pressure, dynamic compliance, and ratio of partial pressure of oxygen in arterial blood to fraction of inspired oxygen (PaO2/FiO2 ratio) were recorded at baseline (T0) and 4 h after instillation (T1-T4). The lung tissue wet-to-dry weight ratio; neutrophil percentage; and total protein, tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-8, prostaglandin E2, and malondialdehyde levels in bronchoalveolar lavage fluid (BALF) were evaluated. The myeloperoxidase activity, COX-2 expression, and degree of histopathologic injury in lung tissue were also analyzed. The airway pressure, compliance, and PaO2/FiO2 ratio were significantly improved by parecoxib after meconium instillation. The lung wet-to-dry weight ratio, total protein level, and neutrophil percentage in BALF were lowest in the parecoxib group. The TNF-α, IL-1β, IL-8, prostaglandin E2, and malondialdehyde levels in the BALF were lowest in the parecoxib group. The COX-2 expression and myeloperoxidase activity in lung tissue were significantly reduced by parecoxib. The degree of lung injury was also reduced. In conclusions: Parecoxib effectively ameliorates respiratory function and attenuates meconium-induced ALI. These effects are correlated with prostaglandin E2 and COX-2 inhibition.

Is the etiology of eosinophilic esophagitis in adults a response to allergy or reflux injury? Study of cellular proliferation markers.

PubMed

Lewis, C J; Lamb, C A; Kanakala, V; Pritchard, S; Armstrong, G R; Attwood, S E A

2009-01-01

Recent research suggests that allergy may be the key factor in the etiology of eosinophilic esophagitis (EE); however, historically, the condition was hypothesized as related to reflux injury to the esophageal mucosa. We studied this hypothesis by comparing markers of inflammation and cellular proliferation in EE and reflux esophagitis. Lower esophageal biopsies of adult patients with EE (n = 10), reflux esophagitis (n = 8), and normal controls (n = 13) were assessed quantitatively for the expression of the cyclooxygenase-2 (COX-2) enzyme, cellular proliferation, and oncogenic resistance to apoptosis using monoclonal antibodies for COX-2, Ki-67, and Bcl-2, respectively. Normal esophageal epithelium demonstrated weak diffuse uptake of COX-2 stain in the basal layer. No COX-2 expression was demonstrated in the EE group, significantly less than the control and reflux groups (P < 0.01 and P < 0.001, respectively). Cellular proliferation measured by Ki-67 expression was higher in EE and reflux compared with control (P < 0.001 and P < 0.01). Ki-67 expression, and thus degree of hyperplasia, appeared greater in EE than reflux, but was not statistically significant (P = 0.228). The degree of apoptosis was similar in all study groups. EE and reflux esophagitis are proliferative conditions expressing Ki-67 in higher concentrations than control. Mucosal proliferation in reflux esophagitis is COX-2 dependent. This novel research in EE has demonstrated downregulation of COX-2 expression compared with reflux esophagitis and control. We hypothesize that the allergy-related cytokine IL-13 known to inhibit COX-2 expression and found in high concentrations in EE as responsible for this. The pathogenesis of EE is likely dependent on allergy rather than reflux injury to the esophagus.

Low levels of Caspase-3 predict favourable response to 5FU-based chemotherapy in advanced colorectal cancer: Caspase-3 inhibition as a therapeutic approach.

PubMed

Flanagan, L; Meyer, M; Fay, J; Curry, S; Bacon, O; Duessmann, H; John, K; Boland, K C; McNamara, D A; Kay, E W; Bantel, H; Schulze-Bergkamen, H; Prehn, J H M

2016-02-04

Colorectal cancer (CRC) is one of the most common cancers in the Western world. 5-Fluorouracil (5FU)-based chemotherapy (CT) remains the mainstay treatment of CRC in the advanced setting, and activates executioner caspases in target cells. Executioner caspases are key proteins involved in cell disassembly during apoptosis. Activation of executioner caspases also has a role in tissue regeneration and repopulation by stimulating signal transduction and cell proliferation in neighbouring, non-apoptotic cells as reported recently. Tissue microarrays (TMAs) consisting of tumour tissue from 93 stage II and III colon cancer patients were analysed by immunohistochemistry. Surprisingly, patients with low levels of active Caspase-3 had an increased disease-free survival time. This was particularly pronounced in patients who received 5FU-based adjuvant CT. In line with this observation, lower serum levels of active Caspase-3 were found in patients with metastasised CRC who revealed stable disease or tumour regression compared with those with disease progression. The role of Caspase-3 in treatment responses was explored further in primary human tumour explant cultures from fresh patient tumour tissue. Exposure of explant cultures to 5FU-based CT increased the percentage of cells positive for active Caspase-3 and Terminal Deoxynucleotidyl Transferase dUTP Nick end Labelling (TUNEL), but also the expression of regeneration and proliferation markers β-Catenin and Ki-67, as well as cyclooxygenase-2 (COX-2). Of note, selective inhibition of Caspase-3 with Ac-DNLD-CHO, a selective, reversible inhibitor of Caspase-3, significantly reduced the expression of proliferation markers as well as COX-2. Inhibition of COX-2 with aspirin or celecoxib did not affect Caspase-3 levels but also reduced Ki-67 and β-Catenin levels, suggesting that Caspase-3 acted via COX-2 to stimulate cell proliferation and tissue regeneration. This indicates that low levels of active Caspase-3 may represent a new predictor of CT responsiveness, and inhibition of Caspase-3, or antagonising downstream effectors of Caspase-3 paracrine signalling, such as COX-2 may improve patient outcomes following CT in advanced CRC.

Immunohistochemical expression of cyclooxygenase-2 (COX-2) in oral nevi and melanoma.

PubMed

de Souza do Nascimento, Juliana; Carlos, Román; Delgado-Azañero, Wilson; Mosqueda Taylor, Adalberto; de Almeida, Oslei Paes; Romañach, Mário José; de Andrade, Bruno Augusto Benevenuto

2016-07-01

Cyclooxygenase-2 (COX-2) catalyses the conversion of arachidonic acid to prostaglandin, and its overexpression has been demonstrated in different malignant tumors, including cutaneous melanoma. However, no data about the expression of this protein in oral melanocytic lesions are available to date. The aim of this study was to evaluate the immunohistochemical expression of COX-2 in oral nevi and melanomas, comparing the results with correspondent cutaneous lesions. COX-2 was evaluated by immunohistochemistry in 49 oral melanocytic lesions, including 36 intramucosal nevi and 13 primary oral melanomas, and in four cutaneous nevi and eight melanomas. All cases of oral and cutaneous melanomas were positive for COX-2. On the other hand, all oral and cutaneous melanocytic nevi were negative. COX-2 is highly positive in oral melanomas and negative in oral nevi and might represent a useful marker to distinguish melanocytic lesions of the oral cavity. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The expression of ERα, OTR, cPLA(2), COX-2, and PPARγ in the cervix of the ewe during the estrous cycle.

PubMed

Falchi, L; Scaramuzzi, R J

2013-01-01

The ovine cervix relaxes at estrus allowing easier entry of spermatozoa into the uterus. The mechanism responsible for this relaxation is not fully elucidated and we hypothesized that cervical relaxation at estrus is induced by ovarian and pituitary hormones stimulating the local production of prostaglandin E(2) via a biosynthetic pathway involving a number of mediators including oxytocin, phospholipase A(2) (cPLA(2)), cyclooxygenase-2 (COX-2), and peroxisome proliferator-activated receptor gamma (PPARγ). The aim of this study was to investigate the cervical expression of estradiol receptor alpha (ERα), oxytocin receptor (OTR), cPLA(2), COX-2, and PPARγ at three stages of the estrous cycle (the luteal phase and two times during the follicular phase, just before and just after the LH surge). An experiment was conducted during the breeding season, in 25 ewes to test this hypothesis. Samples of cervical tissue were collected from groups of ewes at three stages of the estrous cycle: the luteal (N = 8), "pre-LH surge" (N = 8), and "post-LH surge" (N = 9) stages. Cervical tissue from uterine, mid, and vaginal regions of the cervix were analyzed by Western immunoblot analysis for ERα, OTR, cPLA(2,) COX-2, and PPARγ. The results showed that the levels of all five proteins were lowest during the luteal phase of the estrous cycle in all regions of the cervix. The levels of all except cPLA(2), increased significantly during the "pre-LH surge" stage. The levels of cPLA(2) and ERα increased in the "post-LH surge" stage and those for OTR and PPARγ were unchanged and those for COX-2 were lower. These data show that the cervical levels of all five of the intermediates in the synthesis of prostaglandin E(2) that were examined in this study were higher in the "pre-" and "post-LH surge" stages compared with the luteal phase of the estrous cycle and these findings are consistent with our hypothesis. Copyright © 2013 Elsevier Inc. All rights reserved.

Induction of Cyclooxygenase-2 Expression by Hepatitis B Virus Depends on Demethylation-associated Recruitment of Transcription Factors to the Promoter

PubMed Central

2011-01-01

Background The hepatitis B virus (HBV) is a major etiological factor of inflammation and damage to the liver resulting in hepatocellular carcinoma. Transcription factors play important roles in the disordered gene expression and liver injury caused by HBV. However, the molecular mechanisms behind this observation have not been defined. Results In this study, we observed that circulating prostaglandin (PGE) 2 synthesis was increased in patients with chronic hepatitis B infection, and detected elevated cyclooxygenase (COX)-2 expression in HBV- and HBx-expressing liver cells. Likewise, the association of HBx with C/EBPβ contributed to the induction of COX-2. The COX-2 promoter was hypomethylated in HBV-positive cells, and specific demethylation of CpG dinucleotides within each of the two NF-AT sites in the COX-2 promoter resulted in the increased binding affinity of NF-AT to the cognate sites in the promoter, followed by increased COX-2 expression and PGE2 accumulation. The DNA methylatransferase DNMT3B played a key role in the methylation of the COX-2 promoter, and its decreased binding to the promoter was responsible for the regional demethylation of CpG sites, and for the increased binding of transcription factors in HBV-positive cells. Conclusion Our results indicate that upregulation of COX-2 by HBV and HBx is mediated by both demethylation events and recruitment of multiple transcription factors binding to the promoter. PMID:21401943

Inhibitory effects and mechanism of 25-OH-PPD on glomerular mesangial cell proliferation induced by high glucose.

PubMed

Yu, Junxian; Liu, Chunna; Li, Zhe; Zhang, Chao; Wang, Zheng; Liu, Xinyu

2016-06-01

To investigate the protective effects and potential mechanism of the compound 25-OH-PPD (PPD) on the glomerular mesangial cells (GMC) under high glucose condition. The hypertrophic GMC cells were established by DMEM containing glucose and randomly divided into five groups, including the normal control group (Control), the high glucose model group (HG, 25 mmolL(-1)), the PPD low dose group (1μmolL(-1), PPD-L), the PPD middle dose group (5μmolL(-1), PPD -M) and the PPD high dose group (10μmolL(-1), UCN-H). The GMC were incubated for 48h under different treatment factors. Total protein content was determined by Lowry method. The diameter of the single GMC and volume were measured by computer photograph analysis system. The GMC cell viability was analyzed by MTT assay. The level of malondialdehyde (MDA), the content of glutathione (GSH) and superoxide dismutase (SOD) activity were measured by ELISA. [Ca(2+)]і transient was measured by Till image system and by cell-loading Fura-2/AM. The expression of COX-1 and COX-2 were also determined using ELISA method. The viability of GMC and the total protein content were decreased in HG group, different dosage PPD group could increase these indexes (P<0.05). The level of MDA was increased, the content of GSH and SOD was decreased in HG group, while PPD could reduce the MDA and enhance GSH and SOD (P<0.05). Following treatment with different dosage (PPD-L, PPD-M or PPD-H), the [Ca(2+)]і transient was reduced (P<0.05 or P<0.01). Moreover, the expression of COX-1 was decreased while COX-2 expression was increased in different dosage PPD groups. The protective effects of PPD on GMC from HG-induced hypertrophy may be associated with the inhibition of [Ca(2+)]і transient and decreasing expression of COX-1 via the oxidative-stress injure pathway. Copyright © 2016 Elsevier B.V. All rights reserved.

Association between expression of cumulus expansion markers and real-time proliferation of porcine follicular granulosa cells in a primary cell culture model.

PubMed

Ciesiółka, S; Budna, J; Bryja, A; Kranc, W; Chachuła, A; Dyszkiewicz-Konwińska, M; Piotrowska, H; Bukowska, D; Antosik, P; Bruska, M; Brüssow, K P; Nowicki, M; Zabel, M; Kempisty, B

2016-01-01

Folliculogenesis is a compound process that involves both ovarian follicle growth and oocyte development, which is tightly attached to the follicular wall. During this process, cells that form the follicle structure undergo substantial morphological and molecular modifications that finally lead to differentiation and specialization of ovarian follicular cells. The differentiation of ovarian cells encompasses formation of follicle, which is composed of theca (TCs), mural granulosa (GCs), and cumulus cells (CCs). It was previously hypothesized that GCs and CCs represent undifferentiated and highly specialized follicular cells, respectively, which may have similar primordial cell origins. In this study, we investigated the expression pattern of cumulus expansion markers such as COX2, HAS2, PTX3, and TSG6 in porcine GCs during short-term, in vitro culture. We hypothesized that these genes may display an important function in GCs in relation to cellular real-time proliferation. The expression pattern of COX2, HAS2, PTX3, and TSG6 was evaluated after using RT-qPCR in relation to confocal microscopy observations of protein expression and distribution during real-time proliferation of porcine follicular GCs. The COX2 and HAS2 mRNAs were highly expressed after 120 h of in vitro culture (IVC), whereas PTX3 and TSG6 mRNAs were increased during the first 24-48 h of IVC (P less than 0.001, P less than 0.01). Conversely, all of the encoded proteins were highly expressed after 144-168 h of IVC as compared to other culture periods (P less than 0.001, P less than 0.01). When analyzing the realtime proliferation of GCs in vitro, we observed a logarithmic increase of cell proliferation between 0 h and 120 h of IVC. However, after 120-168 h of IVC, the cells reached the lag phase of proliferation. Since it is well accepted that porcine GCs undergo luteinization shortly after 24-48 h of IVC, the expression pattern of investigated genes indicated that Cox2 and Has2 are independent from the LH surge, but their increased levels may be upregulated by cell proliferation in vitro. Moreover, higher expression of PTX3 and TSG6 during first 24 h and/or 48 h of IVC suggested that their levels are accompanied by porcine GCs luteinization process.

Metformin inhibits inflammatory response via AMPK-PTEN pathway in vascular smooth muscle cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Sun Ae; Choi, Hyoung Chul, E-mail: hcchoi@med.yu.ac.kr

2012-09-07

Highlights: Black-Right-Pointing-Pointer PTEN was induced by metformin and inhibited by compound C and AMPK siRNA. Black-Right-Pointing-Pointer Metformin suppressed TNF-{alpha}-induced COX-2 and iNOS mRNA expression. Black-Right-Pointing-Pointer Compound C and bpv (pic) increased iNOS and COX-2 protein expression. Black-Right-Pointing-Pointer NF-{kappa}B activation was restored by inhibiting AMPK and PTEN. Black-Right-Pointing-Pointer AMPK and PTEN regulated TNF-{alpha}-induced ROS production in VSMCs. -- Abstract: Atherosclerosis is a chronic inflammation of the coronary arteries. Vascular smooth muscle cells (VSMCs) stimulated by cytokines and chemokines accelerate the inflammatory response and migrate to the injured endothelium during the progression of atherosclerosis. Activation of AMP activated protein kinase (AMPK), amore » key sensor maintaining metabolic homeostasis, suppresses the inflammatory response. However, how AMPK regulates the inflammatory response is poorly understood. To identify the mechanism of this response, we focused on phosphatase and tensin homolog (PTEN), which is a negative regulator of inflammation. We investigated that activation of AMPK-induced PTEN expression and suppression of the inflammatory response through the AMPK-PTEN pathway in VSMCs. We treated with the well-known AMPK activator metformin to induce PTEN expression. PTEN was induced by metformin (2 mM) and inhibited by compound C (10 {mu}M) and AMPK siRNA. Tumor necrosis factor-alpha (TNF-{alpha}) was used to induce inflammation. The inflammatory response was confirmed by cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS) expression, and activation of nuclear factor (NF)-{kappa}B. Metformin suppressed COX-2 and iNOS mRNA and protein expression dose dependently. Treatment with compound C and bpv (pic) in the presence of metformin, iNOS and COX-2 protein expression increased. NF-{kappa}B activation decreased in response to metformin and was restored by inhibiting AMPK and PTEN. Inhibiting AMPK and PTEN restored ROS levels stimulated with TNF-{alpha}. Taken together, PTEN could be a possible downstream regulator of AMPK, and the AMPK-PTEN pathway might be important in the regulation of the inflammatory response in VSMCs.« less

Expression of VEGF, VEGFR, EGFR, COX-2 and MVD in cervical carcinoma, in relation with the response to radio-chemotherapy.

PubMed

Nagy, Viorica Magdalena; Buiga, R; Brie, Ioana; Todor, N; Tudoran, Oana; Ordeanu, Claudia; Virág, Piroska; Tarta, Oana; Rus, Meda; Bălăcescu, O

2011-01-01

Despite the improvement in the treatment results due to modern irradiation techniques and to the association of chemo-radiotherapy, cervical cancer remains an unsolved problem of oncology both due to the increased rate of local failures and of the distant metastasis. Efforts to implement new therapeutic strategies in order to obtain better results in patients with cervical cancer appear justified. Neovascularization is an important step in the tumor progression and the therapeutic targeting of the tumor blood vessels appears to be a good strategy to follow in the anti-cancer treatment. Thus, even in an incipient phase of the clinical research process, the combination between the anti-angiogenic aimed therapies and the current radio-chemotherapy seems to represent a new, feasible and promising approach. The aim of the present study was to determine the prognostic and/or predictive value of some biological markers of tumor angiogenesis and of their implication in increasing the efficacy of current treatments for this cancer. So far, 54 women were included in a prospective trial: 44 having an advanced cervical carcinoma and 10 healthy women, as controls. A tumor biopsy and a blood sample were obtained from each patient before the start of therapy. The density of microvascularization was assessed using CD34 monoclonal antibody (hot spot technique), the expression of angiogenic factors VEGFR, EGFR and COX-2 were determined in tumor biopsies by specific immunohistochemistry techniques, using primary antibodies anti-EGFR, anti-VEGF and anti-COX-2 respectively. The quantitative polymerase chain reaction (Real Time PCR) was employed for assessing the expression level of the genes involved. Serum VEGF was determined by quantitative ELISA technique. Among the studied clinical and molecular factors, we found to be predictive for the type of response the following factors: tumor size at diagnosis (p=0.01), VEGFR2 expression (p=0.02) and a tendency to significance for patients' age (p=0.06). From the large panel of studied markers it was observed correlation between MVD expression with stromal COX-2 (p=0.01) and a tendency with epithelial COX-2 (p=0.06). Stromal COX-2 has higher correlation with VEGFR2 (p=0.01) and MVD (p=0.01) and also has a lower correlation with tumor size (p=0.08). Univariate analysis demonstrates that the response to radio-chemotherapy in cervical cancer is related to a set of clinical and molecular factors as: the tumor size, the expression of VEGFR2 as mRNA level and the patients' age. Unfortunately, the multivariate analysis by logistic model selects only VEGFR2 expression for prediction of tumor response. The interrelations between the different biomarkers demonstrate the complexity of the tumor progression process and the necessity of further studies to identify new therapeutic targets.

The SK-N-AS human neuroblastoma cell line develops osteolytic bone metastases with increased angiogenesis and COX-2 expression

PubMed Central

Tsutsumimoto, Takahiro; Williams, Paul; Yoneda, Toshiyuki

2014-01-01

Neuroblastoma (NB), which arises from embryonic neural crest cells, is the most common extra-cranial solid tumor of childhood. Approximately half of NB patients manifest bone metastasis accompanied with bone pain, fractures and bone marrow failure, leading to disturbed quality of life and poor survival. To study the mechanism of bone metastasis of NB, we established an animal model in which intracardiac inoculation of the SK-N-AS human NB cells in nude mice developed osteolytic bone metastases with increased osteoclastogenesis. SK-N-AS cells induced the expression of receptor activator of NF-κB ligand and osteoclastogenesis in mouse bone marrow cells in the co-culture. SK-N-AS cells expressed COX-2 mRNA and produced substantial amounts of prostaglandin E2 (PGE2). In contrast, the SK-N-DZ and SK-N-FI human NB cells failed to develop bone metastases, induce osteoclastogenesis, express COX-2 mRNA and produce PGE2. Immunohistochemical examination of SK-N-AS bone metastasis and subcutaneous tumor showed strong expression of COX-2. The selective COX-2 inhibitor NS-398 inhibited PGE2 production and suppressed bone metastases with reduced osteoclastogenesis. NS-398 also inhibited subcutaneous SK-N-AS tumor development with decreased angiogenesis and vascular endothelial growth factor-A expression. Of interest, metastasis to the adrenal gland, a preferential site for NB development, was also diminished by NS-398. Our results suggest that COX2/PGE2 axis plays a critical role in the pathophysiology of osteolytic bone metastases and tumor development of the SK-NS-AS human NB. Inhibition of angiogenesis by suppressing COX-2/PGE2 may be an effective therapeutic approach for children with NB. PMID:26909300

Aldosterone stimulates superoxide production in macula densa cells.

PubMed

Zhu, Xiaolong; Manning, R Davis; Lu, Deyin; Gomez-Sanchez, Celso E; Fu, Yiling; Juncos, Luis A; Liu, Ruisheng

2011-09-01

Two major factors which regulate tubuloglomerular feedback (TGF)-mediated constriction of the afferent arteriole are release of superoxide (O(2)(-)) and nitric oxide (NO) by macula densa (MD) cells. MD O(2)(-) inactivates NO; however, among the factors that increase MD O(2)(-) release, the role of aldosterone is unclear. We hypothesize that aldosterone activates the mineralocorticoid receptor (MR) on MD cells, resulting in increased O(2)(-) production due to upregulation of cyclooxygenase-1 (COX-2) and NOX-2, and NOX-4, isoforms of NAD(P)H oxidase. Studies were performed on MMDD1 cells, a renal epithelial cell line with properties of MD cells. RT-PCR and Western blotting confirmed the expression of MR. Aldosterone (10(-8) mol/l for 30 min) doubled MMDD1 cell O(2)(-) production, and this was completely blocked by MR inhibition with 10(-5) mol/l eplerenone. RT-PCR, real-time PCR, and Western blotting demonstrated aldosterone-induced increases in COX-2, NOX-2, and NOX-4 expression. Inhibition of COX-2 (NS398), NADPH oxidase (apocynin), or a combination blocked aldosterone-induced O(2)(-) production to the same degree. These data suggest that aldosterone-stimulated MD O(2)(-) production is mediated by COX-2 and NADPH oxidase. Next, COX-2 small-interfering RNA (siRNA) specifically decreased COX-2 mRNA without affecting NOX-2 or NOX-4 mRNAs. In the presence of the COX-2 siRNA, the aldosterone-induced increases in COX-2, NOX-2, and NOX-4 mRNAs and O(2)(-) production were completely blocked, suggesting that COX-2 causes increased expression of NOX-2 and NOX-4. In conclusion 1) MD cells express MR; 2) aldosterone increases O(2)(-) production by activating MR; and 3) aldosterone stimulates COX-2, which further activates NOX-2 and NOX-4 and generates O(2)(-). The resulting balance between O(2)(-) and NO in the MD is important in modulating TGF.

Protective effect of hydroxytyrosol in arsenic-induced mitochondrial dysfunction in rat brain.

PubMed

Soni, Manisha; Prakash, Chandra; Sehwag, Sfurti; Kumar, Vijay

2017-07-01

The present study was planned to investigate the protective effect of hydroxytyrosol (HT) against arsenic (As)-induced mitochondrial dysfunction in rat brain. Rats exposed to sodium arsenite (25 ppm for 8 weeks) showed decreased mitochondrial complexes (I, II, IV) activities, mitochondrial superoxide dismutase (MnSOD), and catalase activities in brain mitochondria. As-treated rats showed reduced mRNA expression of complex I (ND-1, ND-2), IV (COX-1, COX-4) subunits, and uncoupling protein-2 (UCP-2). In addition to this, As exposure downregulated the protein expression of MnSOD. Administration of HT with As restored the enzymatic activities of mitochondrial complexes, MnSOD and catalase, increased the mRNA levels of complexes subunits and UCP-2 as well as proteins level of MnSOD. These results suggest that HT efficiently restores mitochondrial dysfunction in As neurotoxicity and might be used as potential mitoprotective agent in future. © 2017 Wiley Periodicals, Inc.

Acrylamide up-regulates cyclooxygenase-2 expression through the MEK/ERK signaling pathway in mouse epidermal cells.

PubMed

Lim, Tae-Gyu; Lee, Bo Kyung; Kwon, Jung Yeon; Jung, Sung Keun; Lee, Ki Won

2011-06-01

Acrylamide is formed during cooking processes and is present in many foods. Accumulating evidence suggests that AA is carcinogenic, but the underlying mechanism remains unclear. Here, we investigated the carcinogenesis mechanisms of AA. AA increased the COX-2 expression. Two major transcription factors, AP-1 and NF-κB, were activated by AA treatment. AA induced the ERK phosphorylation, and this was abolished by the treatment of U0126, a pharmacological inhibitor of MEK, an upstream kinase of ERK. AA-induced expression and promoter activity of COX-2 were suppressed by U0126. U0126 treatment attenuated AA-induced transactivation of AP-1 and NF-κB, suggesting that the MEK/ERK signaling pathway regulates COX-2 expression. In addition, myricetin, a natural inhibitor of the MEK/ERK signal pathway, reduced AA-induced activation of the COX-2 promoter as well as activation of AP-1 and NF-κB. Collectively, these results suggest that the ability of AA to up-regulate COX-2 expression through the MEK/ERK signaling pathway underlies AA carcinogenicity. Copyright © 2011 Elsevier Ltd. All rights reserved.

New Inducible Nitric Oxide Synthase and Cyclooxygenase-2 Inhibitors, Nalidixic Acid Linked to Isatin Schiff Bases via Certain l-Amino Acid Bridges.

PubMed

Naglah, Ahmed M; Ahmed, Atallah F; Wen, Zhi-Hong; Al-Omar, Mohamed A; Amr, Abd El-Galil E; Kalmouch, Atef

2016-04-15

A series of new Schiff bases were synthesized by condensation of isatins with the nalidixic acid-l-amino acid hydrazides. Prior to hydrazide formation, a peptide linkage has been prepared via coupling of nalidixic acid with appropriate l-amino acid methyl esters to yield 3a-c. The chemical structures of the new Schiff bases (5b and 5d-h) were confirmed by means of IR, NMR, mass spectroscopic, and elemental analyses. The anti-inflammatory activity of these Schiff bases was evaluated via measurement of the expressed inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in the lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells model. The Schiff bases exhibited significant dual inhibitory effect against the induction of the pro-inflammatory iNOS and COX-2 proteins with variable potencies. However, they strongly down-regulated the iNOS expression to the level of 16.5% ± 7.4%-42.2% ± 19.6% compared to the effect on COX-2 expression (<56.4% ± 3.1% inhibition) at the same concentration (10 μM). The higher iNOS inhibition activity of the tested Schiff bases, relative to that of COX-2, seems to be a reflection of the combined suppressive effects exerted by their nalidixic acid, isatins (4a-c), and l-amino acid moieties against iNOS expression. These synthesized nalidixic acid-l-amino acid-isatin conjugates can be regarded as a novel class of anti-inflammatory antibacterial agents.

Role of cyclooxygenase-2 in intestinal injury in neonatal rats.

PubMed

Lu, Hui; Zhu, Bing

2014-11-01

Necrotizing enterocolitis (NEC) is the most common gastrointestinal emergency in premature neonates. The pathogenesis of NEC remains poorly understood. The present study aimed to investigate the dynamic change and role of cyclooxygenase-2 (COX-2) in neonatal rats with intestinal injury. Wistar rats, <24 h in age, received an intraperitoneal injection with 5 mg/kg lipopolysaccharide (LPS). Ileal tissues were collected at 1, 3, 6, 12 and 24 h following the LPS challenge for histological evaluation of NEC and for measurements of COX-2 mRNA. The correlation between the degree of intestinal injury and expression of COX-2 mRNA was determined. The LPS-injected pups showed a significant increase in injury scores compared to the control, and the most deteriorating change was at 12 h. COX-2 mRNA expression was upregulated following LPS injection. There was a significantly positive correlation between COX-2 mRNA and the grade of intestinal injury within 12 h, whereas COX-2 mRNA expression had a significantly negative correlation with the severity of intestinal injury at 24 h. COX-2 plays an important role in LPS-induced intestinal injury and the repair processes. Caution should be exerted concerning the potential therapeutic uses of COX-2 inhibitors or promoters in NEC.

Sulforaphane inhibits phorbol ester-stimulated IKK-NF-κB signaling and COX-2 expression in human mammary epithelial cells by targeting NF-κB activating kinase and ERK.

PubMed

Kim, Ha-Na; Kim, Do-Hee; Kim, Eun-Hee; Lee, Mee-Hyun; Kundu, Joydeb Kumar; Na, Hye-Kyung; Cha, Young-Nam; Surh, Young-Joon

2014-08-28

Sulforaphane, an isothiocyanate present in cruciferous vegetables, has been reported to possess anti-inflammatory and cancer chemopreventive properties. However, the molecular mechanisms by which sulforaphane suppresses inflammation and carcinogenesis are yet to be fully elucidated. Since the aberrant expression of cyclooxygenase-2 (COX-2) links inflammation and cancer, the present study was aimed to elucidate the mechanisms by which sulforaphane modulates COX-2 overexpression in human mammary epithelial (MCF-10A) cells stimulated with a prototypic tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). Treatment of MCF-10A cells with sulforaphane significantly inhibited TPA-induced expression of COX-2 protein and its mRNA transcript. Transient transfection of cells with deletion mutant constructs of COX-2 promoter revealed that the transcription factor nuclear factor-kappaB (NF-κB) plays a key role in TPA-induced COX-2 expression in MCF-10A cells. Pretreatment with sulforaphane significantly attenuated nuclear localization, DNA binding and the transcriptional activity of NF-κB through inhibition of phosphorylation and subsequent degradation of IκBα in MCF-10A cells stimulated with TPA. Sulforaphane also attenuated TPA-induced activation of IκB kinases (IKK), NF-κB-activating kinase (NAK) and extracellular signal-regulated kinase-1/2 (ERK1/2). Pharmacological inhibition of IKK or transient transfection of cells with dominant-negative mutant forms of this kinase abrogated TPA-induced NF-κB activation and COX-2 expression. In addition, the blockade of ERK1/2 activation negated the catalytic activity of IKKα, but not that of IKKβ, whereas silencing NAK by specific siRNA abrogated the IKKβ activity in TPA-treated cells. Taken together, sulforaphane inhibits TPA-induced NF-κB activation and COX-2 expression in MCF-10A cells by blocking two distinct signaling pathways mediated by ERK1/2-IKKα and NAK-IKKβ. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Nimesulide, a cyclooxygenase-2 selective inhibitor, suppresses obesity-related non-alcoholic fatty liver disease and hepatic insulin resistance through the regulation of peroxisome proliferator-activated receptor γ.

PubMed

Tsujimoto, Shunsuke; Kishina, Manabu; Koda, Masahiko; Yamamoto, Yasutaka; Tanaka, Kohei; Harada, Yusuke; Yoshida, Akio; Hisatome, Ichiro

2016-09-01

Cyclooxygenase (COX)-2 selective inhibitors suppress non-alcoholic fatty liver disease (NAFLD); however, the precise mechanism of action remains unknown. The aim of this study was to examine how the COX-2 selective inhibitor nimesulide suppresses NAFLD in a murine model of high-fat diet (HFD)‑induced obesity. Mice were fed either a normal chow diet (NC), an HFD, or HFD plus nimesulide (HFD-nime) for 12 weeks. Body weight, hepatic COX-2 mRNA expression and triglyceride accumulation were significantly increased in the HFD group. Triglyceride accumulation was suppressed in the HFD-nime group. The mRNA expression of hepatic peroxisome proliferator-activated receptor γ (PPARγ) and the natural PPARγ agonist 15-deoxy-Δ12,14-prostaglandin J2 (15d‑PGJ2) were significantly increased in the HFD group and significantly suppressed in the HFD-nime group. Glucose metabolism was impaired in the HFD group compared with the NC group, and it was significantly improved in the HFD-nime group. In addition, the plasma insulin levels in the HFD group were increased compared with those in the NC group, and were decreased in the HFD-nime group. These results indicate that HFD-induced NAFLD is mediated by the increased hepatic expression of COX-2. We suggest that the production of 15d-PGJ2, which is mediated by COX-2, induces NAFLD and hepatic insulin resistance by activating PPARγ. Furthermore, the mRNA expression of tissue inhibitor of metalloproteinases-1 (TIMP‑1), procollagen-1 and monocyte chemoattractant protein-1 (MCP-1), as well as the number of F4/80-positive hepatic (Kupffer) cells, were significantly increased in the HFD group compared with the NC group, and they were reduced by nimesulide. In conclusion, COX-2 may emerge as a molecular target for preventing the development of NAFLD and insulin resistance in diet-related obesity.

CRE-Mediated Transcription and COX-2 Expression in the Pilocarpine Model of Status Epilepticus

PubMed Central

Lee, Boyoung; Dziema, Heather; Lee, Kyu Hyun; Choi, Yun-Sik; Obrietan, Karl

2007-01-01

Status epilepticus (SE) triggers neuronal death, reactive gliosis and remodeling of synaptic circuitry, thus leading to profound pathological alterations in CNS physiology. These processes are, in part, regulated by the rapid upregulation of both cytotoxic and cytoprotective genes. One pathway that may couple SE to transcriptionally-dependent alterations in CNS physiology is the CREB (cAMP response element-binding protein)/CRE (cAMP response element) cascade. Here, we utilized the pilocarpine model of SE on a mouse strain transgenic for a CRE-reporter construct (β-galactosidase) to begin to characterize how seizure activity regulates the activation state of the CREB/CRE pathway in both glia and neurons of the hippocampus. SE triggered a rapid (4–8 hrs post SE) but transient increase in CRE-mediated gene expression in the neuronal sublayers. In contrast to neurons, SE induced a lasting increase (up to 20 days) in CRE-mediated transcription in both reactive astrocytes and microglia. CRE-mediated gene expression correlated with expression of the pro-inflammatory enzyme cyclooxygenase-2 (COX-2). To examine the role of CREB in SE-induced COX-2 expression, we generated a transgenic mouse strain that expresses A-CREB, a potent repressor of CREB-dependent transcription. In these animals, the capacity of SE to stimulate COX-2 expression was markedly attenuated, indicating that CREB is a key intermediate in SE-induced COX-2 expression. Collectively these data show that SE triggers two waves of CREB-mediated gene expression, a transient wave in neurons and a long-lasting wave in reactive glial cells, and that CREB couples SE to COX-2 expression. PMID:17029965

Sodium Channel Voltage-Gated Beta 2 Plays a Vital Role in Brain Aging Associated with Synaptic Plasticity and Expression of COX5A and FGF-2.

PubMed

XiYang, Yan-Bin; Wang, You-Cui; Zhao, Ya; Ru, Jin; Lu, Bing-Tuan; Zhang, Yue-Ning; Wang, Nai-Chao; Hu, Wei-Yan; Liu, Jia; Yang, Jin-Wei; Wang, Zhao-Jun; Hao, Chun-Guang; Feng, Zhong-Tang; Xiao, Zhi-Cheng; Dong, Wei; Quan, Xiong-Zhi; Zhang, Lian-Feng; Wang, Ting-Hua

2016-03-01

The role of sodium channel voltage-gated beta 2 (SCN2B) in brain aging is largely unknown. The present study was therefore designed to determine the role of SCN2B in brain aging by using the senescence-accelerated mice prone 8 (SAMP8), a brain senescence-accelerated animal model, together with the SCN2B transgenic mice. The results showed that SAMP8 exhibited impaired learning and memory functions, assessed by the Morris water maze test, as early as 8 months of age. The messenger RNA (mRNA) and protein expressions of SCN2B were also upregulated in the prefrontal cortex at this age. Treatment with traditional Chinese anti-aging medicine Xueshuangtong (Panax notoginseng saponins, PNS) significantly reversed the SCN2B expressions in the prefrontal cortex, resulting in improved learning and memory. Moreover, SCN2B knockdown transgenic mice were generated and bred to determine the roles of SCN2B in brain senescence. A reduction in the SCN2B level by 60.68% resulted in improvement in the hippocampus-dependent spatial recognition memory and long-term potential (LTP) slope of field excitatory postsynaptic potential (fEPSP), followed by an upregulation of COX5A mRNA levels and downregulation of fibroblast growth factor-2 (FGF-2) mRNA expression. Together, the present findings indicated that SCN2B could play an important role in the aging-related cognitive deterioration, which is associated with the regulations of COX5A and FGF-2. These findings could provide the potential strategy of candidate target to develop antisenescence drugs for the treatment of brain aging.

COX-2 Promotes Migration and Invasion by the Side Population of Cancer Stem Cell-Like Hepatocellular Carcinoma Cells

PubMed Central

Guo, Zhe; Jiang, Jing-Hang; Zhang, Jun; Yang, Hao-Jie; Yang, Fu-Quan; Qi, Ya-Peng; Zhong, Yan-Ping; Su, Jie; Yang, Ri-Rong; Li, Le-Qun; Xiang, Bang-De

2015-01-01

Abstract Cancer stem cells (CSCs) are thought to be responsible for tumor relapse and metastasis due to their abilities to self-renew, differentiate, and give rise to new tumors. Cyclooxygenase-2 (COX-2) is highly expressed in several kinds of CSCs, and it helps promote stem cell renewal, proliferation, and radioresistance. Whether and how COX-2 contributes to CSC migration and invasion is unclear. In this study, COX-2 was overexpressed in the CSC-like side population (SP) of the human hepatocellular carcinoma (HCC) cell line HCCLM3. COX-2 overexpression significantly enhanced migration and invasion of SP cells, while reducing expression of metastasis-related proteins PDCD4 and PTEN. Treating SP cells with the selective COX-2 inhibitor celecoxib down-regulated COX-2 and caused a dose-dependent reduction in cell migration and invasion, which was associated with up-regulation of PDCD4 and PTEN. These results suggest that COX-2 exerts pro-metastatic effects on SP cells, and that these effects are mediated at least partly through regulation of PDCD4 and PTEN expression. These results further suggest that celecoxib may be a promising anti-metastatic agent to reduce migration and invasion by hepatic CSCs. PMID:26554780

Increased COX-2 expression in epithelial and stromal cells of high mammographic density tissues and in a xenograft model of mammographic density.

PubMed

Chew, G L; Huo, C W; Huang, D; Hill, P; Cawson, J; Frazer, H; Hopper, J L; Haviv, I; Henderson, M A; Britt, K; Thompson, E W

2015-08-01

Mammographic density (MD) adjusted for age and body mass index is one of the strongest known risk factors for breast cancer. Given the high attributable risk of MD for breast cancer, chemoprevention with a safe and available agent that reduces MD and breast cancer risk would be beneficial. Cox-2 has been implicated in MD-related breast cancer risk, and was increased in stromal cells in high MD tissues in one study. Our study assessed differential Cox-2 expression in epithelial and stromal cells in paired samples of high and low MD human breast tissue, and in a validated xenograft biochamber model of MD. We also examined the effects of endocrine treatment upon Cox-2 expression in high and low MD tissues in the MD xenograft model. Paired high and low MD human breast tissue samples were immunostained for Cox-2, then assessed for differential expression and staining intensity in epithelial and stromal cells. High and low MD human breast tissues were separately maintained in biochambers in mice treated with Tamoxifen, oestrogen or placebo implants, then assessed for percentage Cox-2 staining in epithelial and stromal cells. Percentage Cox-2 staining was greater for both epithelial (p = 0.01) and stromal cells (p < 0.0001) of high compared with low MD breast tissues. In high MD biochamber tissues, percentage Cox-2 staining was greater in stromal cells of oestrogen-treated versus placebo-treated tissues (p = 0.05).

HPV16 E6 Promotes Breast Cancer Proliferation via Upregulation of COX-2 Expression

PubMed Central

Li, Y. Z.; Zhang, Z. Y.; Wang, J. Q.

2017-01-01

Background. Breast cancer remains the leading cause of cancer-related mortality worldwide. It has been indicated that human papillomaviruses 16 (HPV16) might participate in the pathogenesis and development of breast cancer. However, the detected rate of HPV16 varies with region. We will investigate HPV16 E6 expression in North China and explore the effects and mechanism of HPV16 E6 on breast cancer proliferation in this study. Methods. The expressions of HPV16 E6 and COX-2 in paraffin-embedded tissues of the invasive ductal breast cancer were detected by qPCR and IHC. The effects of HPV16 E6 on breast cancer proliferation were determined by function studies. The mechanism of HPV16 E6 in promoting breast cancer proliferation was explored by Western blot and Dual-Luciferase Reporter Assay. Results. HPV16 E6 was positive in 28% invasive ductal breast carcinoma in North China; HPV16 E6 promoted breast cancer proliferation. Inhibition of COX-2 by siCOX-2 or Celecoxib attenuated the proliferation of breast cancer cells with HPV16 E6 expression; and the upregulation of COX-2 could be suppressed by the inhibition of NF-κB activity. Conclusion. HPV16 E6 promotes breast cancer proliferation by activation of NF-κB signaling pathway and increase of COX-2 expression. COX-2 will be a potential target for HPV16 E6-associated breast cancer. PMID:29250535

The Effect of PSD-93 Deficiency on the Expression of Early Inflammatory Cytokines Induced by Ischemic Brain Injury.

PubMed

Zhang, Qingxiu; Cheng, Hongyu; Rong, Rong; Yang, Hui; Ji, Qiuhong; Li, Qingjie; Rong, Liangqun; Hu, Gang; Xu, Yun

2015-12-01

The aim of the study was to explore the effect of PSD-93 deficiency on the expression of early inflammatory cytokines induced by cerebral ischemia/reperfusion injury. Ten- to twelve-week-old male PSD-93 knockout (PSD-93 KO) mice (C57BL/6 genetic background) and wild-type (WT) littermates were randomly divided into sham and ischemia/reperfusion (I/R) group. The focal cerebral I/R model was established by middle cerebral artery occlusion (MCAO) suture method. RT-PCR was used to detect the mRNA expression of IL-6, IL-10, Cox-2, iNOS, and TNF-α4h following reperfusion. Infarct volume at different time points after I/R was analyzed using 2,3,5-triphenyl tetrazolium staining, and neurological damage score (neurological severity scores, NSS) was used to evaluate the effect of PSD-93 gene knockout on the MCAO-induced neurological injury. In WT mice, early I/R injury led to the increase in the mRNA expression of proinflammatory cytokines IL-6, Cox-2, iNOS, and TNF-α that coincided with the decrease in the expression of anti-inflammatory cytokine IL-10, as compared to the sham group (P < 0.05). This effect was markedly attenuated by depleting PSD-93 levels by gene knockout. As compared to sham group, in PSD-93 KO mice I/R4h led to downregulation of Cox-2 and iNOS expression, and increase in the mRNA levels of IL-10 (P < 0.05). In addition, following MCAO, PSD-93 KO mice exhibited improved NSS and reduced infarct volumes, as compared with WT animals. PSD-93 knockout may play a neuroprotective role by mediating the early release of inflammatory cytokines induced by cerebral ischemia.

Cyclooxygenase-2 up-regulates CCR7 expression via AKT-mediated phosphorylation and activation of Sp1 in breast cancer cells.

PubMed

Chuang, Chun-Wei; Pan, Mei-Ren; Hou, Ming-Feng; Hung, Wen-Chun

2013-02-01

Up-regulation of cyclooxygenase-2 (COX-2) is frequently found in human cancers and is significantly associated with tumor metastasis. Our previous results demonstrate that COX-2 and its metabolite prostaglandin E2 (PGE2) stimulate the expression of CCR7 chemokine receptor via EP2/EP4 receptors to promote lymphatic invasion in breast cancer cells. In this study, we address the underlying mechanism of COX-2/PGE2-induced CCR7 expression. We find that COX-2/PGE2 increase CCR7 expression via the AKT signaling pathway in breast cancer cells. Promoter deletion and mutation assays identify the Sp1 site located at the -60/-57 region of CCR7 gene promoter is critical for stimulation. Chromatin immunoprecipitation (ChIP) assay confirms that in vivo binding of Sp1 to human CCR7 promoter is increased by COX-2 and PGE2. Knockdown of Sp1 by shRNA reduces the induction of CCR7 by PGE2. We demonstrate for the first time that AKT may directly phosphorylate Sp1 at S42, T679, and S698. Phosphorylation-mimic Sp1 protein harboring S42D, T679D, and S698D mutation strongly activates CCR7 expression. In contrast, change of these three residues to alanine completely blocks the induction of CCR7 by PGE2. Pathological investigation demonstrates that CCR7 expression is strongly associated with phospho-AKT and Sp1 in 120 breast cancer tissues. Collectively, our results demonstrate that COX-2 up-regulates CCR7 expression via AKT-mediated phosphorylation and activation of Sp1 and this pathway is highly activated in metastatic breast cancer. Copyright © 2012 Wiley Periodicals, Inc.

Aryl Hydrocarbon Receptor-Dependent Retention of Nuclear HuR Suppresses Cigarette Smoke-Induced Cyclooxygenase-2 Expression Independent of DNA-Binding

PubMed Central

Zago, Michela; Sheridan, Jared A.; Nair, Parameswaran; Rico de Souza, Angela; Gallouzi, Imed-Eddine; Rousseau, Simon; Di Marco, Sergio; Hamid, Qutayba; Eidelman, David H.; Baglole, Carolyn J.

2013-01-01

The aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor that responds to man-made environmental toxicants, has emerged as an endogenous regulator of cyclooxygenase-2 (Cox-2) by a mechanism that is poorly understood. In this study, we first used AhR-deficient (AhR−/−) primary pulmonary cells, together with pharmacological tools to inhibit new RNA synthesis, to show that the AhR is a prominent factor in the destabilization of Cox-2 mRNA. The destabilization of Cox-2 mRNA and subsequent suppression of cigarette smoke-induced COX-2 protein expression by the AhR was independent of its ability to bind the dioxin response element (DRE), thereby differentiating the DRE-driven toxicological AhR pathway from its anti-inflammatory abilities. We further describe that the AhR destabilizes Cox-2 mRNA by sequestering HuR within the nucleus. The role of HuR in AhR stabilization of Cox-2 mRNA was confirmed by knockdown of HuR, which resulted in rapid Cox-2 mRNA degradation. Finally, in the lungs of AhR−/− mice exposed to cigarette smoke, there was little Cox-2 mRNA despite robust COX-2 protein expression, a finding that correlates with almost exclusive cytoplasmic HuR within the lungs of AhR−/− mice. Therefore, we propose that the AhR plays an important role in suppressing the expression of inflammatory proteins, a function that extends beyond the ability of the AhR to respond to man-made toxicants. These findings open the possibility that a DRE-independent AhR pathway may be exploited therapeutically as an anti-inflammatory target. PMID:24086407

Aryl hydrocarbon receptor-dependent retention of nuclear HuR suppresses cigarette smoke-induced cyclooxygenase-2 expression independent of DNA-binding.

PubMed

Zago, Michela; Sheridan, Jared A; Nair, Parameswaran; Rico de Souza, Angela; Gallouzi, Imed-Eddine; Rousseau, Simon; Di Marco, Sergio; Hamid, Qutayba; Eidelman, David H; Baglole, Carolyn J

2013-01-01

The aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor that responds to man-made environmental toxicants, has emerged as an endogenous regulator of cyclooxygenase-2 (Cox-2) by a mechanism that is poorly understood. In this study, we first used AhR-deficient (AhR(-/-) ) primary pulmonary cells, together with pharmacological tools to inhibit new RNA synthesis, to show that the AhR is a prominent factor in the destabilization of Cox-2 mRNA. The destabilization of Cox-2 mRNA and subsequent suppression of cigarette smoke-induced COX-2 protein expression by the AhR was independent of its ability to bind the dioxin response element (DRE), thereby differentiating the DRE-driven toxicological AhR pathway from its anti-inflammatory abilities. We further describe that the AhR destabilizes Cox-2 mRNA by sequestering HuR within the nucleus. The role of HuR in AhR stabilization of Cox-2 mRNA was confirmed by knockdown of HuR, which resulted in rapid Cox-2 mRNA degradation. Finally, in the lungs of AhR(-/-) mice exposed to cigarette smoke, there was little Cox-2 mRNA despite robust COX-2 protein expression, a finding that correlates with almost exclusive cytoplasmic HuR within the lungs of AhR(-/-) mice. Therefore, we propose that the AhR plays an important role in suppressing the expression of inflammatory proteins, a function that extends beyond the ability of the AhR to respond to man-made toxicants. These findings open the possibility that a DRE-independent AhR pathway may be exploited therapeutically as an anti-inflammatory target.

Anti-inflammatory effect of sophoraflavanone G isolated from Sophora flavescens in lipopolysaccharide-stimulated mouse macrophages.

PubMed

Wun, Zih-Yi; Lin, Chwan-Fwu; Huang, Wen-Chung; Huang, Yu-Ling; Xu, Pei-Yin; Chang, Wei-Tien; Wu, Shu-Ju; Liou, Chian-Jiun

2013-12-01

Sophoraflavanone G (SG; 5,7,D, 2',4'-tetrahydroxy-8-lavandulylflavanone) has been isolated from Sophora flavescens and found to be effective against bacteria and to decrease cyclooxygenase (COX)-2 expression in RAW 264.7 macrophage. However, the anti-inflammatory mechanisms of SG are not well understood. RAW 264.7 cells were pretreated with various concentrations of SG (2.5-20 μM) and inflammatory responses were induced with lipopolysaccharide. Using enzyme-linked immunosorbent assay, the levels of pro-inflammatory cytokines and prostaglandin E2 (PGE2) were determined. Western blot was used to examine the protein expression of inducible nitric oxide synthase (iNOS), COX-2, and heme oxygenase-1 (HO-1). To investigate the molecular mechanism, we analyzed inflammatory-associated signaling pathways, including nuclear transcription factor kappa-B (NF-κB) and mitogen-activated protein kinase (MAPK). SG inhibited the levels of nitric oxide and PGE2 and decreased the production of pro-inflammatory cytokines, such as interleukin (IL)-1β, IL-6, and tumor necrosis factor α. The expression of iNOS and COX-2 was also suppressed. However, SG increased HO-1 production in a concentration-dependent manner and significantly decreased MAPK activation and inhibited NF-κB subunit p65 proteins to translocate into the nucleus. These results suggest that SG has an anti-inflammatory effect, inhibiting pro-inflammatory cytokines and mediators production via interruption of the NF-κB and MAPK signaling pathways. Copyright © 2013 Elsevier Ltd. All rights reserved.

COX-derived prostanoid pathways in gastrointestinal cancer development and progression: novel targets for prevention and intervention.

PubMed

Cathcart, Mary-Clare; O'Byrne, Kenneth J; Reynolds, John V; O'Sullivan, Jacintha; Pidgeon, Graham P

2012-01-01

Arachidonic acid metabolism through cyclooxygenase (COX) pathways leads to the generation of biologically active eicosanoids. Eicosanoid expression levels vary during development and progression of gastrointestinal (GI) malignancies. COX-2 is the major COX-isoform responsible for G.I. cancer development/progression. COX-2 expression increases during progression from a normal to cancerous state. Evidence from observational studies has demonstrated that chronic NSAID use reduces the risk of cancer development, while both incidence and risk of death due to G.I. cancers were significantly reduced by daily aspirin intake. A number of randomized controlled trials (APC trial, Prevention of Sporadic Adenomatous Polyps trial, APPROVe trial) have also shown a significant protective effect in patients receiving selective COX-2 inhibitors. However, chronic use of selective COX-2 inhibitors at high doses was associated with increased cardiovascular risk, while NSAIDs have also been associated with increased risk. More recently, downstream effectors of COX-signaling have been investigated in cancer development/progression. PGE(2), which binds to both EP and PPAR receptors, is the major prostanoid implicated in the carcinogenesis of G.I. cancers. The role of TXA(2) in G.I. cancers has also been examined, although further studies are required to uncover its role in carcinogenesis. Other prostanoids investigated include PGD(2) and its metabolite 15d-PGJ2, PGF(1α) and PGI(2). Targeting these prostanoids in G.I. cancers has the promise of avoiding cardiovascular toxicity associated with chronic selective COX-2 inhibition, while maintaining anti-tumor reactivity. A progressive sequence from normal to pre-malignant to a malignant state has been identified in G.I. cancers. In this review, we will discuss the role of the COX-derived prostanoids in G.I. cancer development and progression. Targeting these downstream prostanoids for chemoprevention and/or treatment of G.I. cancers will also be discussed. Finally, we will highlight the latest pre-clinical technologies as well as avenues for future investigation in this highly topical research field. Copyright © 2011 Elsevier B.V. All rights reserved.

Brain inflammation and Alzheimer's-like pathology in individuals exposed to severe air pollution.

PubMed

Calderón-Garcidueñas, Lilian; Reed, William; Maronpot, Robert R; Henríquez-Roldán, Carlos; Delgado-Chavez, Ricardo; Calderón-Garcidueñas, Ana; Dragustinovis, Irma; Franco-Lira, Maricela; Aragón-Flores, Mariana; Solt, Anna C; Altenburg, Michael; Torres-Jardón, Ricardo; Swenberg, James A

2004-01-01

Air pollution is a complex mixture of gases (e.g., ozone), particulate matter, and organic compounds present in outdoor and indoor air. Dogs exposed to severe air pollution exhibit chronic inflammation and acceleration of Alzheimer's-like pathology, suggesting that the brain is adversely affected by pollutants. We investigated whether residency in cities with high levels of air pollution is associated with human brain inflammation. Expression of cyclooxygenase-2 (COX2), an inflammatory mediator, and accumulation of the 42-amino acid form of beta-amyloid (Abeta42), a cause of neuronal dysfunction, were measured in autopsy brain tissues of cognitively and neurologically intact lifelong residents of cities having low (n:9) or high (n:10) levels of air pollution. Genomic DNA apurinic/apyrimidinic sites, nuclear factor-kappaB activation and apolipoprotein E genotype were also evaluated. Residents of cities with severe air pollution had significantly higher COX2 expression in frontal cortex and hippocampus and greater neuronal and astrocytic accumulation of Abeta42 compared to residents in low air pollution cities. Increased COX2 expression and Abeta42 accumulation were also observed in the olfactory bulb. These findings suggest that exposure to severe air pollution is associated with brain inflammation and Abeta42 accumulation, two causes of neuronal dysfunction that precede the appearance of neuritic plaques and neurofibrillary tangles, hallmarks of Alzheimer's disease.

Methamphetamine toxicity-induced calcineurin activation, nuclear translocation of nuclear factor of activated T-cells and elevation of cyclooxygenase 2 levels are averted by calpastatin overexpression in neuroblastoma SH-SY5Y cells.

PubMed

Chetsawang, Jirapa; Nudmamud-Thanoi, Sutisa; Phonchai, Ruchee; Abubakar, Zuroida; Govitrapong, Piyarat; Chetsawang, Banthit

2018-06-23

Methamphetamine (METH) is an addictive stimulant drug that has many negative consequences, including toxic effects to the brain. Recently, the induction of inflammatory processes has been identified as a potential contributing factor to induce neuronal cell degeneration. It has been demonstrated that the expression of inflammatory agents, such as cyclooxygenase 2 (COX-2), depends on the activation of calcineurin (CaN) and nuclear factor of activated T-cells (NFAT). Moreover, the excessive elevation in cytosolic Ca 2+ levels activates the cell death process, including calpain activation in neurons, which was diminished by the overexpression of the calpain inhibitor protein, calpastatin. However, it is unclear whether calpain mediates CaN-NFAT activation in the neurotoxic process. In the present study, we observed that the toxic high dose of METH-treated neuroblastoma SH-SY5Y cells significantly decreased cell viability but increased apoptotic cell death, the active cleaved form of calcineurin, the nuclear translocation of NFAT, and COX-2 levels. Nevertheless, these toxic effects were diminished in METH-treated calpastatin-overexpressing SH-SY5Y cells. These findings might emphasize the role of calpastatin against METH-induced toxicity by a mechanism related to calpain-dependent CaN-NFAT activation-induced COX-2 expression. Copyright © 2018. Published by Elsevier B.V.

Clinicopathological and prognostic significance of cyclooxygenase-2 expression in head and neck cancer: A meta-analysis

PubMed Central

Guo, Qiaojuan; Ren, Hui; Hu, Yanping; Xie, Tao

2016-01-01

Several studies have assessed the clinicopathological and prognostic value of cyclooxygenase-2 (COX-2) expression in patients with head and neck cancer (HNC), but their results remain controversial. To address this issue, a meta-analysis was carried out. A total of 29 studies involving 2430 patients were subjected to final analysis. Our results indicated that COX-2 expression was not statistically associated with advanced tumor stage (OR, 1.23; 95% CI, 0.98–1.55) but correlated with high risk of lymph node metastasis (OR, 1.28; 95% CI, 1.03–1.60) and advanced TNM stage (OR, 1.33; 95% CI, 1.06–1.66). Moreover, COX-2 expression had significant effect on poor OS (HR, 1.93; 95% CI, 1.29–2.90), RFS (HR, 2.02; 95% CI, 1.00–4.08) and DFS (HR, 5.14; 95% CI, 2.84–9.31). The results of subgroup analyses revealed that COX-2 expression was related with high possibility of lymph node metastasis in oral cancer (OR, 1.49; 95% CI, 1.01–2.20) and advanced TNM stage in oral cancer (OR, 1.58; 95% CI, 1.05–2.37) and no site-specific HNC (OR, 1.64; 95% CI, 1.02–2.62). However, subgroup analyses only showed a tendency without statistically significant association between COX-2 expression and survival. Significant heterogeneity was not found when analyzing clinicopathological data, but it appeared when considering survival data. No publication bias was detected in this study. This meta-analysis suggested that COX-2 expression could act as a prognostic factor for patients with HNC. PMID:27323811

Early life stress and later peer distress on depressive behavior in adolescent female rats: Effects of a novel intervention on GABA and D2 receptors.

PubMed

Lukkes, Jodi L; Meda, Shirisha; Thompson, Britta S; Freund, Nadja; Andersen, Susan L

2017-07-14

Early life adversity (ELA) increases the risk of depression during adolescence that may result from a decline in parvalbumin (PVB) secondary to increased neuroinflammation. In this study, we investigated depressive-like behavior following exposure to two different types of stressors that are relevant for their developmental period: 1) chronic ELA (maternal separation; MS) and 2) an acute emotional stressor during adolescence (witnessing their peers receive multiple shocks; WIT), and their interaction. We also determined whether reducing inflammation by cyclooxygenase-2 (COX-2) inhibition would prevent the onset of depressive-like behavior. Female Sprague-Dawley rat pups underwent MS for four-hours/day or received typical care (CON) between postnatal days (P) 2 and P20. A COX-2 inhibitor (COX-2I) or vehicle was administered every other day between P30 and P38. Subjects were tested for learned helplessness to assess depressive-like behavior at P40 (adolescence). MS females demonstrated increased escape latency and decreased PVB in the prefrontal cortex (PFC) and dorsal raphe that were attenuated by COX-2I intervention. Helplessness was also associated with an increase in D2 receptors in the accumbens. In contrast, WIT elevated escape latency in CON, but reduced latency in MS females. Furthermore, COX-2I intervention decreased escape latency in both CON and MS after WIT. WIT reduced PVB levels in the basolateral amygdala and increased PFC levels to CON levels. Our data suggest that decreased PVB in the PFC is important for the expression of depressive-like behavior and suggest that COX-2I intervention may provide a novel prevention for depression. Copyright © 2017 Elsevier B.V. All rights reserved.

Epigallocatechin-3-gallate blocks triethylene glycol dimethacrylate-induced cyclooxygenase-2 expression by suppressing extracellular signal-regulated kinase in human dental pulp and embryonic palatal mesenchymal cells.

PubMed

Yang, Wan-Hsien; Deng, Yi-Ting; Kuo, Mark Yen-Ping; Liu, Cheing-Meei; Chang, Hao-Hueng; Chang, Jenny Zwei-Chieng

2013-11-01

Methacrylate resin-based materials could release components into adjacent environment even after polymerization. The major components leached include triethylene glycol dimethacrylate (TEGDMA). TEGDMA has been shown to induce the expression of cyclooxygenase-2 (COX-2). However, the mechanisms are not completely understood. The aims of this study were to investigate the molecular mechanism underlying TEGDMA-induced COX-2 in 2 oral cell types, the primary culture of human dental pulp (HDP) cells and the human embryonic palatal mesenchymal (HEPM) pre-osteoblasts, and to propose potential strategy to prevent or ameliorate the TEGDMA-induced inflammation in oral tissues. TEGDMA-induced COX-2 expression and its signaling pathways were assessed by Western blot analyses in HDP and HEPM cells. The inhibition of TEGDMA-induced COX-2 protein expression using various dietary phytochemicals was investigated. COX-2 protein expression was increased after exposure to TEGDMA at concentrations as low as 5 μmol/L. TEGDMA-induced COX-2 expression was associated with reaction oxygen species, the extracellular signal-regulated kinase 1/2, and the p38 mitogen-activated protein kinase signaling pathways in HDP and HEPM cells. The activation of p38 mitogen-activated protein kinase was directly associated with reactive oxygen species. Epigallocatechin-3-gallate suppressed TEGDMA-induced COX-2 expression by inhibiting phosphorylation of extracellular signal-regulated kinase 1/2. Cells exposed to low concentrations of TEGDMA may induce inflammatory responses of the adjacent tissues, and this should be taken into consideration during common dental practice. Green tea, which has a long history of safe beverage consumption, may be a useful agent for the prevention or treatment of TEGDMA-induced inflammation in oral tissues. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Upregulation of Cyclooxygenase-2 Expression in Porcine Macula Densa With Chronic Nitric Oxide Synthase Inhibition

PubMed Central

Kommareddy, M.; McAllister, R. M.; Ganjam, V. K.; Turk, J. R.; Laughlin, M. Harold

2012-01-01

The objective of this study was to investigate the effects of chronic inhibition of nitric oxide synthase (NOS) on cyclooxygenase-2 (COX-2) expression in the macula densa (MD) of swine, as well as the effects on expression of related proteins. Adult female Yucatan swine were given either tap water (control, n = 6) or water with NG-nitro-l-arginine methyl ester (L-NAME, 100 mg/liter, n = 5) for a minimum of 30 days. Duplicate samples of kidney were fixed or snap frozen. There was a significant (P = .0082) upregulation of COX-2 mRNA expression in the MD of L-NAME, as well as an apparent increase in COX-2 protein. Plasma renin activity also increased with L-NAME treatment (control, 0.34 ± 0.08 ng/ml; L-NAME, 1.26 ± 0.03 ng/ml; P = .00000003). There were no differences between groups in expression of either inducible NOS or renin protein or in serum electrolyte concentrations. In conclusion, with chronic inhibition of NOS, COX-2 in MD is upregulated, perhaps to compensate for loss of nitric oxide. Increases in COX-2 products may counteract renal arteriolar constriction and sustain renin release. PMID:21160023

Upregulation of cyclooxygenase-2 expression in porcine macula densa with chronic nitric oxide synthase inhibition.

PubMed

Kommareddy, M; McAllister, R M; Ganjam, V K; Turk, J R; Laughlin, M Harold

2011-11-01

The objective of this study was to investigate the effects of chronic inhibition of nitric oxide synthase (NOS) on cyclooxygenase-2 (COX-2) expression in the macula densa (MD) of swine, as well as the effects on expression of related proteins. Adult female Yucatan swine were given either tap water (control, n = 6) or water with N (G)-nitro-L-arginine methyl ester (L-NAME, 100 mg/liter, n = 5) for a minimum of 30 days. Duplicate samples of kidney were fixed or snap frozen. There was a significant (P = .0082) upregulation of COX-2 mRNA expression in the MD of L-NAME, as well as an apparent increase in COX-2 protein. Plasma renin activity also increased with L-NAME treatment (control, 0.34 ± 0.08 ng/ml; L-NAME, 1.26 ± 0.03 ng/ml; P = .00000003). There were no differences between groups in expression of either inducible NOS or renin protein or in serum electrolyte concentrations. In conclusion, with chronic inhibition of NOS, COX-2 in MD is upregulated, perhaps to compensate for loss of nitric oxide. Increases in COX-2 products may counteract renal arteriolar constriction and sustain renin release.

Antioxidative effects of cinnamomi cortex: A potential role of iNOS and COX-II

PubMed Central

Chung, Jin-Won; Kim, Jeong-Jun; Kim, Sung-Jin

2011-01-01

Background: Cinnamomi cortex has wide varieties of pharmacological actions such as anti-inflammatory action, anti-platelet aggregation, and improving blood circulation. In this study, we tested to determine whether the Cinnamomi cortex extract has antioxidant activities. Materials and Methods: Antioxidative actions were explored by measuring free radical scavenging activity, NO levels, and reducing power. The mechanism of antioxidative action of Cinnamomi cortex was determined by measuring iNOS and COX-II expression in lipopolysaccharide (LPS) stimulated Raw cells. Results: Seventy percent methanolic extract of Cinnamomi cortex exerted significant 1,1-diphenyl--2--picrylhydrazyl (DPPH) free radicals and NO scavenging activities in a dose-dependent manner. More strikingly, the Cinnamomi cortex extract exerted dramatic reducing power activity (13-fold over control). Production of iNOS induced by LPS was significantly inhibited by the Cinnamomi cortex extract, suggesting that it inhibits NO production by suppressing iNOS expression. Additionally, COX-2 induced by LPS was dramatically inhibited by the Cinnamomi cortex extract. Conclusion: These results suggest that 70% methanolic extract of Cinnamomi cortex exerts significant antioxidant activity via inhibiting iNOS and COX-II induction. PMID:22262934

Lentiviral Infection of Rhesus Macaques Causes Long-Term Injury to Cortical and Hippocampal Projections of Prostaglandin-Expressing Cholinergic Basal Forebrain Neurons

PubMed Central

Depboylu, Candan; Weihe, Eberhard; Eiden, Lee E.

2011-01-01

The simian immunodeficiency virus (SIV) macaque model resembles human HIV-AIDS and associated brain dysfunction. Altered expression of synaptic markers and transmitters in neuro-AIDS has been reported, but limited data exist for the cholinergic system and lipid mediators such as prostaglandins. Here, we analyzed cholinergic basal forebrain neurons with their telencephalic projections and the rate-limiting enzymes for prostaglandin synthesis, cyclooxygenases 1 and 2 (COX1 and 2) in brains of SIV-infected macaques with and without encephalitis and antiretroviral therapy, and uninfected controls. COX1 but not COX2 was co-expressed with markers of cholinergic phenotype, i.e. choline acetyltransferase and vesicular acetylcholine transporter (VAChT), in basal forebrain neurons of monkey, as well as human samples. COX1 was decreased in basal forebrain neurons in macaques with AIDS vs. uninfected and asymptomatic SIV-infected macaques. VAChT-positive fiber density was reduced in frontal, parietal and hippocampal-entorhinal cortex. Although brain SIV burden and associated COX1- and COX2-positive mononuclear and endothelial inflammatory reactions were mostly reversed in AIDS-diseased macaques that received 6-chloro-2′,3′-dideoxyguanosine treatment, decreased VAChT-positive terminal density and reduced cholinergic COX1 expression were not. Thus, COX1 expression is a feature of primate cholinergic basal forebrain neurons; it may be functionally important and a critical biomarker of cholinergic dysregulation accompanying lentiviral encephalopathy. These results imply that insufficiently prompt initiation of antiretroviral therapy in lentiviral infection may lead to neurostructurally unremarkable but neurochemically prominent, irreversible brain damage. PMID:22157616

Cyclooxygenase system contributes to the maintenance of post convulsive period of epileptic phenomena in the genetically epileptic El mice.

PubMed

Okada, Kazumasa; Yamashita, Uki; Tsuji, Sadatoshi

2006-09-01

Recent studies have shown that cytokines and cyclooxygenase (COX)-2 are up-regulated in the brain of human epilepsy patients and animal models of epilepsy. We investigated the effect of inflammatory responses induced by intramuscular injection of turpentine on the epileptic phenomenon in genetically epileptic El mice. As parameters of epileptic seizure, seizure threshold (number of toss-ups to induce convulsion), duration of actual convulsion and duration of post actual convulsive period (period from the offset of convulsion to full recovery) were evaluated. The post actual convulsive period was prolonged without any change of seizure threshold or duration of actual convulsion 24 h after turpentine injection. Although pretreatment with indomethacin for one week did not change the seizure parameters, indomethacin suppressed the prolongation of the post actual convulsive period induced by turpentine. The mRNA expression of IL-1beta, IL-6 and COX-2 in the cerebral cortex was detected by RT-PCR. There was no difference in the mRNA expression in the cerebral cortex before and 24 h after seizure. The mRNA levels of IL-1beta, IL-6 and COX-2 in the cerebral cortex were up-regulated 24 h after turpentine injection. On the other hand, the up-regulated mRNA levels of IL-1beta, IL-6 and COX-2 in the cerebral cortex after turpentine treatment were not suppressed by indomethacin. These results suggest that prostaglandins induced with COX-2 in the cerebral cortex seem to play an important role in the maintenance of the post convulsive period, but not in induction and maintenance of the actual convulsive state.

P38 AND EGF RECEPTOR KINASE-MEDIATED ACTIVATION OF THE PHOSPHATIDYLINOSITOL 3-KINASE/AKT PATHWAY IS REQUIRED FOR ZN2+INDUCED CYCLOOXYGENASE-2 EXPRESSION

EPA Science Inventory

Cyclooxygenase 2 (COX-2) expression is induced by physiological and inflammatory stimuli. Regulation of COX-2 expression is stimulus- and cell type-specific. Exposure to Zn2+ has been associated with activation of multiple intracellular signaling pathways as well as the induction...

Hydrogen Sulfide Improves Endothelial Dysfunction via Downregulating BMP4/COX-2 Pathway in Rats with Hypertension.

PubMed

Xiao, Lin; Dong, Jing-Hui; Jin, Sheng; Xue, Hong-Mei; Guo, Qi; Teng, Xu; Wu, Yu-Ming

2016-01-01

Aims. We object to elucidate that protective effect of H2S on endothelium is mediated by downregulating BMP4 (bone morphogenetic protein 4)/cyclooxygenase- (COX-) 2 pathway in rats with hypertension. Methods and Results. The hypertensive rat model induced by two-kidney one-clip (2K1C) model was used. Exogenous NaHS administration (56 μmol/kg/day, intraperitoneally once a day) reduced mean arterial pressure (MAP) of 2K1C rats from 199.9 ± 3.312 mmHg to 159.4 ± 5.434 mmHg, while NaHS did not affect the blood pressure in the Sham rats and ameliorated endothelium-dependent contractions (EDCs) of renal artery in 2K1C rats. 2K1C reduced CSE level twofold, decreased plasma levels of H2S about 6-fold, increased BMP4, Nox2, and Nox4 levels 2-fold and increased markers of oxidative stress MDA and nitrotyrosine 1.5-fold, upregulated the expression of phosphorylation-p38 MAPK 2-fold, and increased protein levels of COX-2 1.5-fold, which were abolished by NaHS treatment. Conclusions. Our results demonstrate that H2S prevents activation of BMP4/COX-2 pathway in hypertension, which may be involved in the ameliorative effect of H2S on endothelial impairment. These results throw light on endothelial protective effect of H2S and provide new target for prevention and therapy of hypertension.

Nucleobindin Co-Localizes and Associates with Cyclooxygenase (COX)-2 in Human Neutrophils

PubMed Central

Leclerc, Patrick; Biarc, Jordane; St-Onge, Mireille; Gilbert, Caroline; Dussault, Andrée-Anne; Laflamme, Cynthia; Pouliot, Marc

2008-01-01

The inducible cyclooxygenase isoform (COX-2) is associated with inflammation, tumorigenesis, as well as with physiological events. Despite efforts deployed in order to understand the biology of this multi-faceted enzyme, much remains to be understood. Nucleobindin (Nuc), a ubiquitous Ca2+-binding protein, possesses a putative COX-binding domain. In this study, we investigated its expression and subcellular localization in human neutrophils, its affinity for COX-2 as well as its possible impact on PGE2 biosynthesis. Complementary subcellular localization approaches including nitrogen cavitation coupled to Percoll fractionation, immunofluorescence, confocal and electron microscopy collectively placed Nuc, COX-2, and all of the main enzymes involved in prostanoid synthesis, in the Golgi apparatus and endoplasmic reticulum of human neutrophils. Immunoprecipitation experiments indicated a high affinity between Nuc and COX-2. Addition of human recombinant (hr) Nuc to purified hrCOX-2 dose-dependently caused an increase in PGE2 biosynthesis in response to arachidonic acid. Co-incubation of Nuc with COX-2-expressing neutrophil lysates also increased their capacity to produce PGE2. Moreover, neutrophil transfection with hrNuc specifically enhanced PGE2 biosynthesis. Together, these results identify a COX-2-associated protein which may have an impact in prostanoid biosynthesis. PMID:18493301

Prevotella intermedia induces prostaglandin E2 via multiple signaling pathways.

PubMed

Guan, S-M; Fu, S-M; He, J-J; Zhang, M

2011-01-01

Prostaglandin E(2) (PGE(2)) plays important roles in the bone resorption of inflammatory diseases such as rheumatoid arthritis and periodontitis via specific prostaglandin receptors (i.e., EP1-EP4). In this study, the authors examined whether Prevotella intermedia regulates PGE(2) production and EP expression in human periodontal ligament fibroblasts (hPDLs); they also explored the potential signaling pathways involved in PGE(2) production. P. intermedia induced PGE(2) production and cyclooxygenase-2 (COX-2) expression in a dose- and time-dependent manner. Indomethacin and NS-398 completely abrogated the P. intermedia-induced PGE(2) production without modulating COX-2 expression. Specific inhibitors of extracellular signal-regulated kinase, c-Jun N-terminal kinase, p38, phosphatidylinositol 3-kinase, and protein kinase C--but not c-AMP and protein kinase A--significantly attenuated the P. intermedia-induced COX-2 and PGE(2) expression. P. intermedia reduced EP1 expression in a concentration- and time-dependent manner. The results indicate that the COX-2-dependent induction of PGE(2) by P. intermedia in hPDLs is mediated by multiple signaling pathways.

Effect of DanQi Pill on PPARα, lipid disorders and arachidonic acid pathway in rat model of coronary heart disease.

PubMed

Chang, Hong; Wang, Qiyan; Shi, Tianjiao; Huo, Kuiyuan; Li, Chun; Zhang, Qian; Wang, Guoli; Wang, Yuanyuan; Tang, Binghua; Wang, Wei; Wang, Yong

2016-03-22

Danqi pill (DQP) is one of the most widely prescribed formulas and has been shown to have remarkable protective effect on coronary heart disease (CHD). However, its regulatory effects on lipid metabolism disorders haven't been comprehensively studied so far. We aimed to explore the effects of DQP on Peroxisome Proliferator activated receptors α (PPARα), lipid uptake-transportation-metabolism pathway and arachidonic acid (AA)-mediated inflammation pathway in rats with CHD. 80 Sprague-Dawley (SD) Rats were randomly divided into sham group, model group, positive control group and DQP group. Rat model of CHD was induced by ligation of left ventricle anterior descending artery and fed with high fat diet in all but the sham group. Rats in sham group only underwent thoracotomy. After surgery, rats in the positive control and DQP group received daily treatments of pravastatin and DQP respectively. At 28 days after surgery, rats were sacrificed and plasma lipids were evaluated by plasma biochemical detection. Western blot and PCR were applied to evaluate the expressions of PPARα, proteins involved in lipid metabolism and AA pathways. Twenty eight days after surgery, dyslipidemia developed in CHD model rats, as illustrated by elevated plasma lipid levels. Expressions of apolipoprotein A-I (ApoA-I), cluster of differentiation 36 (CD36) and fatty acid binding protein (FABP) in the heart tissues of model group were down-regulated compared with those in sham group. Expressions of carnitine palmitoyl transferase I (CPT-1A) and lipoproteinlipase (LPL) were also reduced significantly. In addition, levels of phospholipase A2 (PLA2) and cyclooxygenase 2 (COX-2) were up-regulated. Expressions of Nuclear factor-κB (NF- κB) and signal transducer and activator of transcription 3 (STAT3) also increased. Furthermore, Expression of PPARα decreased in the model group. DQP significantly up-regulated expressions of ApoA-I and FABP, as well as the expressions of CPT-1A and CD36. In addition, DQP down-regulated expressions of PLA2, COX-2 and NF-κB in inflammation pathway. Levels of STAT3 and LPL were not affected by DQP treatment. In particular, DQP up-regulated PPARα level significantly. DQP could effectively regulate lipid uptake-transportation-metabolism process in CHD model rats, and the effect is achieved mainly by activating ApoA-I-CD36-CPT-1A molecules. Interestingly, DQP can up-regulate expression of PPARα significantly. The anti-inflammatory effect of DQP is partly exerted by inhibiting expressions of PLA2-COX2 -NF-κB pathway.

Comparable Molecular Alterations in 4-Nitroquinoline 1-Oxide-induced Oral and Esophageal Cancer in Mice and in Human Esophageal Cancer, Associated with Poor Prognosis of Patients

PubMed Central

YANG, ZHENGDUO; GUAN, BAOXIANG; MEN, TAOYAN; FUJIMOTO, JUNYA; XU, XIAOCHUN

2013-01-01

Background The murine model of 4-nitroquinoline 1-oxide (4-NQO)-induced oral and esophageal cancer is frequently used to assess the effects of different cancer prevention/therapy agents in vivo, but the molecular mechanisms in those 4-NQO-induced carcinogenesis are unknown. This study investigated aberrant expression of cell growth-critical genes in 4-NQO-induced oral and esophageal cancer tissues in mice compared to human disease for association with survival of patients. Materials and Methods C57LB6/129Sv mice were given 4-NQO in their drinking water to induce oral and esophageal cancer. Quantitative-reverse transcription polymerase chain reaction (qRT-PCR), western blot, and immunohistochemistry were used to detect gene expression in the cancer tissues from mice and in 4-NQO-treated human esophageal cancer cell lines and esophageal cancer tissues. Methylation-specific PCR and DNA sequencing were performed to assess methylation of Rarb2 promoter in murine tissues. Kaplan-Meier analysis was performed to associate gene expression in esophageal cancer tissues with survival data for patients with esophageal cancer. Results 4-NQO dose-dependently induced pre-malignant and malignant lesions in oral cavity and esophagus in mice that pathologically and morphologically mimicked human oral and esophageal cancer. Molecularly, 4-NQO inhibited Rarβ2 but induced expression of phosphorylated extracellular-signal-regulated kinase 1 and 2 (p-ERK1/2) and Cox2 proteins and Rarβ2 gene promoter methylation in murine tumors. In vitro treatment with 4-NQO altered expression of RARβ2, p-ERK1/2, and COX2 in human esophageal cancer cells. In tissues from 90 patients with esophageal cancer, expression of p-ERK1/2 and COX2 was up-regulated, and p-ERK1/2 expression was associated with advanced clinical tumor stage and consumption of hot beverages, while COX2 expression was associated with tumor de-differentiation in esophageal cancer. Furthermore, expression of p-ERK1/2 was associated with a worse overall survival rate of patients (p=0.014), whereas the association of COX2 expression with worse overall survival rate did not reach statistical significance (p=0.19). Knockdown of COX2 expression using transient transfection of a COX2 antisense expression vector inhibited Ki67 expression, an indicator of cell proliferation, in human esophageal cancer cells. Conclusion 4-NQO-induced cancer in oral cavity and esophagus of mice not only pathologically and morphologically mimicked human oral and esophageal cancer but also shared some molecular alterations (e.g. aberrant expression of Rarb2, p-ERK1/2, and Cox2). This study further demonstrated that targeting of the altered RARβ2-led gene pathway could effectively suppress development of this deadly type of cancer. PMID:23812217

Cyanidin-3-glucoside suppresses B[a]PDE-induced cyclooxygenase-2 expression by directly inhibiting Fyn kinase activity.

PubMed

Lim, Tae-Gyu; Kwon, Jung Yeon; Kim, Jiyoung; Song, Nu Ry; Lee, Kyung Mi; Heo, Yong-Seok; Lee, Hyong Joo; Lee, Ki Won

2011-07-15

Benzo[a]pyrene-7,8-diol-9,10-epoxide (B[a]PDE) is a well-known carcinogen that is associated with skin cancer. Abnormal expression of cyclooxygenase-2 (COX-2) is an important mediator in inflammation and tumor promotion. We investigated the inhibitory effect of cyanidin-3-glucoside (C3G), an anthocyanin present in fruits, on B[a]PDE-induced COX-2 expression in mouse epidermal JB6 P+ cells. Pretreatment with C3G resulted in the reduction of B[a]PDE-induced expression of COX-2 and COX-2 promoter activity. The activation of activator protein-1 (AP-1) and nuclear factor-κB (NF-κB) induced by B[a]PDE was also attenuated by C3G. C3G attenuated the B[a]PDE-induced phosphorylation of MEK, MKK4, Akt, and mitogen-activated protein kinases (MAPKs), but no effect on the phosphorylation of the upstream MAPK regulator Fyn. However, kinase assays demonstrated that C3G suppressed Fyn kinase activity and C3G directly binds Fyn kinase noncompetitively with ATP. By using PP2, a pharmacological inhibitor for SFKs, we showed that Fyn kinase regulates B[a]PDE-induced COX-2 expression by activating MAPKs, AP-1 and NF-κB. These results suggest that C3G suppresses B[a]PDE-induced COX-2 expression mainly by blocking the activation of the Fyn signaling pathway, which may contribute to its chemopreventive potential. Copyright © 2011 Elsevier Inc. All rights reserved.

Cyclooxygenase Expression and Platelet Function in Healthy Dogs Receiving Low Dose Aspirin

PubMed Central

Dudley, Alicia; Thomason, John; Fritz, Sara; Grady, Jesse; Stokes, John; Wills, Robert; Pinchuk, Lesya; Mackin, Andrew; Lunsford, Kari

2014-01-01

Background Low dose aspirin is used to prevent thromboembolic complications in dogs, but some animals are non-responsive to the anti-platelet effects of aspirin (‘aspirin resistance’). Hypothesis/Objectives That low dose aspirin would inhibit platelet function, decrease thromboxane synthesis, and alter platelet cyclooxygenase (COX) expression. Animals Twenty-four healthy dogs Methods A repeated measures study. Platelet function (PFA-100® closure time, collagen/epinephrine), platelet COX-1 and COX-2 expression, and urine 11-dehydro-thromboxane B2 (11-dTXB2) was evaluated prior to and during aspirin administration (1 mg/kg Q24 hours PO, 10 days). Based on prolongation of closure times after aspirin administration, dogs were divided into categories according to aspirin responsiveness: responders, non-responders, and inconsistent responders. Results Low dose aspirin increased closure times significantly (62% by Day 10, P<0.001), with an equal distribution among aspirin responsiveness categories, 8 dogs per group. Platelet COX-1 mean fluorescent intensity (MFI) increased significantly during treatment, 13% on Day 3 (range, −29.7%–136.1%) (P=0.047) and 72% on Day 10 (range, −0.37–210.36%) (P<0.001). Platelet COX-2 MFI increased significantly by 34% (range, −29.2–270.4%) on Day 3 (P = 0.003) and 74% (range, −19.7–226.2%) on Day 10 (P<0.001). Urinary 11-dTXB2 concentrations significantly (P=0.005, P<0.001) decreased at both time points. There was no difference between aspirin responsiveness and either platelet COX expression or thromboxane production. Conclusions and Clinical Importance Low dose aspirin consistently inhibits platelet function in approximately one third of healthy dogs, despite decreased thromboxane synthesis and increased platelet COX expression in most dogs. Pre-treatment COX isoform expression did not predict aspirin resistance. PMID:23278865

An Anacardiaceae preparation reduces the expression of inflammation-related genes in murine macrophages.

PubMed

Leiro, J; García, D; Arranz, J A; Delgado, R; Sanmartín, M L; Orallo, F

2004-08-01

This study investigated the effects of an aqueous extract of the stem bark of Mangifera indica L. (Anacardiaceae; Vimang), which contains a defined mixture of components including polyphenols (principally mangiferin, MA), triterpenes, phytosteroids, fatty acids and microelements, on expression of inflammation mediators in inflammatory murine macrophages after stimulation in vitro with lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma). In vitro treatment with Vimang at 4 microg/ml reduced levels of NOS-2 mRNA and NOS-2, while treatment at 40 microg/ml also reduced levels of COX-2 mRNA, COX-2, and prostaglandin E2 (PGE2). Results suggested that MA is involved in these effects. In vitro treatment with Vimang at 40 microg/ml also inhibited mRNA levels of the proinflammatory cytokines interleukin 1beta (IL-1beta), tumor necrosis factor alpha (TNF-alpha) and colony-stimulating factor (GM-CSF), but did not affect mRNA levels of IL-6 or tumor growth factor-beta (TGF-beta). Extracellular release of TNF-alpha by inflammatory macrophages was inhibited by in vitro treatment with Vimang at the same concentrations that showed inhibition of TNF-alpha mRNA levels. The inhibition of TNF-alpha production appears to be at least partially attributable to MA. Vimang at 4 microg/ml decreased mRNA levels of nuclear factor-kappaB (NF-kappaB) but did not affect expression of the NF-kappaB inhibitor (IkappaB). These data indicate that the potent anti-inflammatory effects of Vimang are due to selective modulation of the expression of inflammation-related genes, leading to attenuation of macrophage activation.

Activating PTEN by COX-2 inhibitors antagonizes radiation-induced AKT activation contributing to radiosensitization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meng, Zhen; Department of Oral & Maxillofacial Surgery, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081; Gan, Ye-Hua, E-mail: kqyehuagan@bjmu.edu.cn

2015-05-01

Radiotherapy is still one of the most effective nonsurgical treatments for many tumors. However, radioresistance remains a major impediment to radiotherapy. Although COX-2 inhibitors can induce radiosensitization, the underlying mechanism is not fully understood. In this study, we showed that COX-2 selective inhibitor celecoxib enhanced the radiation-induced inhibition of cell proliferation and apoptosis in HeLa and SACC-83 cells. Treatment with celecoxib alone dephosphorylated phosphatase and tensin homolog deleted on chromosome ten (PTEN), promoted PTEN membrane translocation or activation, and correspondingly dephosphorylated or inactivated protein kinase B (AKT). By contrast, treatment with radiation alone increased PTEN phosphorylation, inhibited PTEN membrane translocationmore » and correspondingly activated AKT in the two cell lines. However, treatment with celecoxib or another COX-2 selective inhibitor (valdecoxib) completely blocked radiation-induced increase of PTEN phosphorylation, rescued radiation-induced decrease in PTEN membrane translocation, and correspondingly inactivated AKT. Moreover, celecoxib could also upregulate PTEN protein expression by downregulating Sp1 expression, thereby leading to the activation of PTEN transcription. Our results suggested that COX-2 inhibitors could enhance radiosensitization at least partially by activating PTEN to antagonize radiation-induced AKT activation. - Highlights: • COX-2 inhibitor, celecoxib, could enhance radiosensitization. • Radiation induced PTEN inactivation (phosphorylation) and AKT activation. • COX-2 inhibitor induced PTEN expression and activation, and inactivated AKT. • COX-2 inhibitor enhanced radiosensitization through activating PTEN.« less

Betulinic acid exerts anti-hepatitis C virus activity via the suppression of NF-κB- and MAPK-ERK1/2-mediated COX-2 expression.

PubMed

Lin, Chun-Kuang; Tseng, Chin-Kai; Chen, Kai-Hsun; Wu, Shih-Hsiung; Liaw, Chih-Chuang; Lee, Jin-Ching

2015-06-23

This study was designed to evaluate the effect of betulinic acid (BA), extracted from Avicennia marina, on the replication of hepatitis C virus (HCV) and to investigate the mechanism of this BA-mediated anti-HCV activity. HCV replicon and infectious systems were used to evaluate the anti-HCV activity of BA. Exogenous COX-2 or knock-down of COX-2 expression was used to investigate the role of COX-2 in the anti-HCV activity of BA. The effects of BA on the phosphorylation of NF-κB and on kinases in the MAPK signalling pathway were determined. The anti-HCV activity of BA in combination with other HCV inhibitors was also determined to assess its use as an anti-HCV supplement. BA inhibited HCV replication in both Ava5 replicon cells and in a cell culture-derived infectious HCV particle system. Treatment with a combination of BA and IFN-α, the protease inhibitor telaprevir or the NS5B polymerase inhibitor sofosbuvir resulted in the synergistic suppression of HCV RNA replication. Exogenous overexpression of COX-2 gradually attenuated the inhibitory effect of BA on HCV replication, suggesting that BA reduces HCV replication by suppressing the expression of COX-2. In particular, BA down-regulated HCV-induced COX-2 expression by reducing the phosphorylation of NF-κB and ERK1/2 of the MAPK signalling pathway. BA inhibits HCV replication by suppressing the NF-κB- and ERK1/2-mediated COX-2 pathway and may serve as a promising compound for drug development or as a potential supplement for use in the treatment of HCV-infected patients. © 2015 The British Pharmacological Society.

Flavanols from Japanese quince (Chaenomeles japonica) fruit suppress expression of cyclooxygenase-2, metalloproteinase-9, and nuclear factor-kappaB in human colon cancer cells.

PubMed

Owczarek, Katarzyna; Hrabec, Elżbieta; Fichna, Jakub; Sosnowska, Dorota; Koziołkiewicz, Maria; Szymański, Jacek; Lewandowska, Urszula

2017-01-01

Natural polyphenols and polyphenol-rich extracts have been found to possess preventive and therapeutic potential against several types of cancers, including colorectal cancer (CRC), which is an example of an inflammation-associated cancer. This study examines the chemopreventive effect of a Japanese quince (Chaenomeles japonica) fruit flavanol preparation (JQFFP) on colon cancer SW-480 cells. JQFFP, rich in procyanidin monomers and oligomers, was found to inhibit the SW-480 cell viability by 40% at 150 µM catechin equivalents (CE) after 72 h incubation when compared to control, but it was non-toxic to normal colon fibroblast CCD-18Co cells. Furthermore, 100 µM CE JQFFP suppressed COX-2 mRNA expression to 36.7% of control values and protein expression to 77%. In addition, JQFFP reduced the MMP-9 protein expression (to 24% vs. control at 100 µM CE) and caused inhibition of its enzymatic activity (to 35% vs. control at 100 µM CE). Not only did JQFFP inhibit the COX-2 and MMP-9 levels, but it also reduced the NF-κB protein expression (to 65% of control) and phosphorylation of its p65 subunit (to 51%) at 100 µM CE. These results provide the first evidence that JQFFP inhibits COX-2, MMP-9, and NF-κB expression, suggesting that it has cytotoxic, anti-inflammatory, and anti-metastatic activities towards the colon cancer SW-480 cells.

COX2 expression and Erk1/Erk2 activity mediate Cot-induced cell migration.

PubMed

Rodríguez, Cristina; López, Pilar; Pozo, Maite; Duce, Antonio Martín; López-Pelaéz, Marta; Fernández, Margarita; Alemany, Susana

2008-09-01

The MAPKKK8 Cot/tpl-2, identified as an oncogene (Cot-T), participates in the intracellular signaling activated by members of the TLR and TNFalpha receptor superfamilies. Here we demonstrate that Cot promotes cell migration by regulating different steps involved in this process, such as cell adhesion and metalloproteinase activity. Indeed, Cot also regulates the cytoskeleton and Cot-T overexpression provokes the polarization of microtubules and the loss of stress fibers. Moreover, and in accordance with the increased Rac-GTP levels observed, Cot-T overexpressing cells develop more lamellipodia than control cells. Conversely, depletion of endogenous Cot increases the formation of stress fibers which is correlated with the high levels of Rho-GTP observed in these cells. In addition, the increase in COX2 expression and the activation of Erk1/2 regulated by Cot are essential for the induction of cell migration. Together, these data provide evidence of a new role for both proto-oncogenic and oncogenic Cot.

The endocannabinoid system expression in the female reproductive tract is modulated by estrogen.

PubMed

Maia, J; Almada, M; Silva, A; Correia-da-Silva, G; Teixeira, N; Sá, S I; Fonseca, B M

2017-11-01

The endocannabinoid system (ECS) is involved in several physiological events that resulted in a growing interest in its modulation. Moreover, the uterine levels of anandamide (AEA), the major endocannabinoid, must be tightly regulated to create proper embryo implantation conditions. However, there are no evidences about the regulation of AEA in uterus by estrogen. Thus, the aim of this study is to elucidate whether estradiol benzoate (EB) and tamoxifen (TAM) administration to ovariectomized (OVX) rats can induce changes in the expression of cannabinoid receptors and AEA-metabolic enzymes in uterus by evaluating gene transcription and protein levels by qPCR, Western blot and immunohistochemistry. Moreover, the plasmatic and uterine levels of AEA and of prostaglandin E 2 (PGE 2 ) and prostaglandin F 2 α (PGF 2α ), the major cyclooxygenase-2 (COX-2) products, were determined by UPLC-MS/MS. The immunohistochemistry showed that cannabinoid receptors, as well as AEA-metabolic enzymes are mainly located in the epithelial cells of both lumen and glands and, to a lesser extent, in the muscle cells. Moreover, EB administration to OVX rats significantly increased CB1, CB2, NAPE-PLD, FAAH and COX-2 expression and transcription. These effects were absent in TAM and TAM+EB treatments showing that this response is estrogen receptor dependent. Additionally, although uterine levels of AEA remained unchanged in EB or TAM treated animals, they showed a rise with EB treatment in plasma. The latter also produced a decrease in uterine PGE 2 levels. In summary, these data collectively indicate that the expression of ECS components, as well as, the AEA and PGE 2 levels in rat uterus is modulated by EB. Thus, estradiol may have a direct regulatory role in the modulation of ECS in female reproductive tissues. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of Cyclooxygenase on the Urothelium of the Urinary Bladder of Mice Exposed to Pelvic Radiation.

PubMed

Ozbilgin, M Kemal; Onal, Tuna; Ozcan, Cemil; Temel, Merve; Aktas, Caner; Gareveran, Manuchehr Salehi; Uluer, Elgin Turkoz; Inan, Sevinc; Kurtman, Cengiz

2016-04-01

To determine the role of cyclooxygenase (COX) expression in the urothelium of the urinary bladder during radiation injury caused by pelvic radiotherapy for cancer therapy. Twenty-four male Swiss Albino mice were separated into 4 groups. The first group was the control group (Group 1) and the second, third, and fourth groups were euthanized after 24 hours (Group 2), 48 hours (Group 3), and 7 days (Group 4), respectively. A single-fractioned 10 Gy of ionizing radiation was applied to all mice's pelvic zone with Co-60. Bladders were removed completely from the pelvic region. Histochemical analysis using hematoxylin and eosin and immunohistochemical analysis using anti-COX-1 and COX-2 antibodies were performed on tissue samples. The immunoreactivities of the urinary bladder were quantified using H-score measurement, and statistical comparison was performed. In the immunohistochemical examination the COX-1 immunoreactivities were found to be higher in the urothelium of the bladder in the radiation exposed groups than in the normal control group (group 1) (p < 0.005). Additionally, high immunoreactivity of COX-2 molecule was established in groups 2, 3, and 4 of radiation groups as compared to group 1 (p < 0.005) in examination of the urothelium. COX-1 and COX-2 immunoreactivities in the submucosa were detected higher in group 4 than in the other groups (p < 0.005). COX-1 and COX-2 expressions in the urothelium and subepithelium of the urinary bladder were investigated in mice during the acute radiation response. The expression of COX-1 and COX-2 in the urothelium seems to prevent bladder damage from radiation, supplying differentiation and restoration of the urothelium.

Aluminium induced oxidative stress results in decreased mitochondrial biogenesis via modulation of PGC-1α expression.

PubMed

Sharma, Deep Raj; Sunkaria, Aditya; Wani, Willayat Yousuf; Sharma, Reeta Kumari; Kandimalla, Ramesh J L; Bal, Amanjit; Gill, Kiran Dip

2013-12-01

The present investigation was carried out to elucidate a possible molecular mechanism related to the effects of aluminium-induced oxidative stress on various mitochondrial respiratory complex subunits with special emphasis on the role of Peroxisome proliferator activated receptor gamma co-activator 1α (PGC-1α) and its downstream targets i.e. Nuclear respiratory factor-1(NRF-1), Nuclear respiratory factor-2(NRF-2) and Mitochondrial transcription factor A (Tfam) in mitochondrial biogenesis. Aluminium lactate (10mg/kgb.wt./day) was administered intragastrically to rats for 12 weeks. After 12 weeks of exposure, we found an increase in ROS levels, mitochondrial DNA oxidation and decrease in citrate synthase activity in the Hippocampus (HC) and Corpus striatum (CS) regions of rat brain. On the other hand, there was a decrease in the mRNA levels of the mitochondrial encoded subunits-NADH dehydrogenase (ND) subunits i.e. ND1, ND2, ND3, Cytochrome b (Cytb), Cytochrome oxidase (COX) subunits i.e. COX1, COX3, ATP synthase (ATPase) subunit 6 along with reduced expression of nuclear encoded subunits COX4, COX5A, COX5B of Electron transport chain (ETC). Besides, a decrease in mitochondrial DNA copy number and mitochondrial content in both regions of rat brain was observed. The PGC-1α was down-regulated in aluminium treated rats along with NRF-1, NRF-2 and Tfam, which act downstream from PGC-1α in aluminium treated rats. Electron microscopy results revealed a significant increase in the mitochondrial swelling, loss of cristae, chromatin condensation and decreases in mitochondrial number in case of aluminium treated rats as compared to control. So, PGC-1α seems to be a potent target for aluminium neurotoxicity, which makes it an almost ideal target to control or limit the damage that has been associated with the defective mitochondrial function seen in neurodegenerative diseases. © 2013.

Determination of Dietary Iron Requirements by Full Expression of Iron-Containing Enzymes in Various Tissues of Broilers.

PubMed

Ma, Xinyan; Liao, Xiudong; Lu, Lin; Li, Sufen; Zhang, Liyang; Luo, Xugang

2016-11-01

The current dietary iron requirement (80 mg/kg) of broilers is mainly based on growth, hemoglobin concentration, or hematocrit data obtained in a few early studies; however, expressions of iron-containing enzymes might be more sensitive novel criteria to evaluate dietary iron requirements. The objective of this study was to determine dietary iron requirements of broilers for the full expression of succinate dehydrogenase (SDH), catalase, and cytochrome c oxidase (COX) in various tissues. A total of 336 1-d-old Arbor Acres male chicks were randomly assigned to 1 of 7 treatments with 6 replicates and fed a basal corn and soybean-meal diet (control, containing 67 mg Fe/kg) and the basal diet supplemented with 20, 40, 60, 80, 100, or 120 mg Fe/kg from FeSO 4 ⋅ 7H 2 O for 21 d. Regression analysis was performed to estimate the optimal dietary iron concentration with the use of broken-line or quadratic models. SDH activity in the liver and heart, COX and catalase activity in the liver, Sdh mRNA levels in the liver, and Cox mRNA levels in the liver and heart of broilers were affected (P < 0.027) by supplemental iron concentration, and increased quadratically (P < 0.004) as dietary iron concentration increased. Dietary iron requirements estimated on the basis of fitted broken-line or quadratic-curve models (P < 0.005) of the above indexes were 97-136 mg/kg. SDH activity in the liver and heart, COX and catalase activity in the liver, Sdh mRNA levels in the liver, and Cox mRNA levels in the liver and heart are, to our knowledge, new and sensitive criteria to evaluate the dietary iron requirements of broilers, and the dietary iron requirements would be 97-136 mg/kg to support the full expression of the above iron-containing enzymes in various tissues of broiler chicks from 1 to 21 d of age, which are higher than the current NRC iron requirement. © 2016 American Society for Nutrition.

Tangeretin suppresses IL-1beta-induced cyclooxygenase (COX)-2 expression through inhibition of p38 MAPK, JNK, and AKT activation in human lung carcinoma cells.

PubMed

Chen, Kuan-Hung; Weng, Meng-Shih; Lin, Jen-Kun

2007-01-15

Tangeretin (5,6,7,8,4'-pentamethoxyflavone) is a polymethoxylated flavonoid concentrated in the peel of citrus fruits. Recent studies have shown that tangeretin exhibits anti-proliferative, anti-invasive, anti-metastatic, and antioxidant activities. However, the anti-inflammatory properties of tangeretin are unclear. In this study, we examine the effects of tangeretin and its structure-related compound, nobiletin, on the expression of cyclooxygenases-2 (COX-2) in human lung epithelial carcinoma cells, A549, and human non-small cell lung carcinoma cells, H1299. Tangeretin exerts a much better inhibitory activity than nobiletin against IL-1beta-induced production of COX-2 in A549 cells, and it effectively represses the constitutively expressed COX-2 in H1299. RT-PCR was used to investigate the transcriptional inhibition of COX-2 by tangeretin. COX-2 mRNA was rapidly induced by IL-1beta in 3h and markedly suppressed by tangeretin. IL-1beta-induced the activation of ERK, p38 MAPK, JNK, and AKT in A549 cells. COX-2 expression in response to IL-1beta was attenuated by pretreatment with SB203580, SP600125, and LY294002, but not with PD98059, suggesting the involvement of p38 MAPK, JNK, and PI3K in this response. Pretreatment of cells with tangeretin inhibited IL-1beta-induced p38 MAPK, JNK, and AKT phosphorylation and the downstream activation of NF-kappaB. These results may reveal that the tangeretin inhibition of IL-1beta-induced COX-2 expression in A549 cells is, at least in part, mediated through suppression of NF-kappaB transcription factor as well as through suppression of the signaling proteins of p38 MAPK, JNK, and PI3K, but not of ERK.

Myricetin down-regulates phorbol ester-induced cyclooxygenase-2 expression in mouse epidermal cells by blocking activation of nuclear factor kappa B.

PubMed

Lee, Kyung Mi; Kang, Nam Joo; Han, Jin Hee; Lee, Ki Won; Lee, Hyong Joo

2007-11-14

Abnormal expression of cyclooxygenase-2 (COX-2) has been implicated in the development of cancer. There are multiple lines of evidence that red wine exerts chemopreventive effects, and 3,5,4'-trihydroxy- trans-stilbene (resveratrol), which is a non-flavonoid polyphenol found in red wine, has been reported to be a natural chemopreventive agent. However, other phytochemicals might contribute to the cancer-preventive activities of red wine, and the flavonol content of red wines is about 30 times higher than that of resveratrol. Here we report that 3,3',4',5,5',7-hexahydroxyflavone (myricetin), one of the major flavonols in red wine, inhibits 12-O-tetradecanoylphorbol-13-acetate (phorbol ester)-induced COX-2 expression in JB6 P+ mouse epidermal (JB6 P+) cells by suppressing activation of nuclear factor kappa B (NF-kappaB). Myricetin at 10 and 20 microM inhibited phorbol ester-induced upregulation of COX-2 protein, while resveratrol at the same concentration did not exert significant effects. The phorbol ester-induced production of prostaglandin E 2 was also attenuated by myricetin treatment. Myricetin inhibited both COX-2 and NF-kappaB transactivation in phorbol ester-treated JB6 P+ cells, as determined using a luciferase assay. Myricetin blocked the phorbol ester-stimulated DNA binding activity of NF-kappaB, as determined using an electrophoretic mobility shift assay. Moreover, TPCK (N-tosyl-l-phenylalanine chloromethyl ketone), a NF-kappaB inhibitor, significantly attenuated COX-2 expression and NF-kappaB promoter activity in phorbol ester-treated JB6 P+ cells. In addition, red wine extract inhibited phorbol ester-induced COX-2 expression and NF-kappaB transactivation in JB6 P+ cells. Collectively, these data suggest that myricetin contributes to the chemopreventive effects of red wine through inhibition of COX-2 expression by blocking the activation of NF-kappaB.

Maternal Betaine Supplementation during Gestation Enhances Expression of mtDNA-Encoded Genes through D-Loop DNA Hypomethylation in the Skeletal Muscle of Newborn Piglets.

PubMed

Jia, Yimin; Song, Haogang; Gao, Guichao; Cai, Demin; Yang, Xiaojing; Zhao, Ruqian

2015-11-25

Betaine has been widely used in animal and human nutrition to promote muscle growth and performance, yet it remains unknown whether maternal betaine supplementation during gestation affects the metabolic characteristics of neonatal skeletal muscles. In the present study, feeding sows with betaine-supplemented diets throughout gestation significantly upregulated the expression of mtDNA-encoded OXPHOS genes (p < 0.05), including COX1, COX2, and ND5, in the muscle of newborn piglets, which was associated with enhanced mitochondrial COX enzyme activity (p < 0.05). Concurrently, maternal betaine supplementation increased the plasma betaine concentration and muscle expression of methyl transfer enzymes (p < 0.05), BHMT and GNMT, in offspring piglets. Nevertheless, Dnmt3a was downregulated at the level of both mRNA and protein, which was associated with a hypomethylated mtDNA D-loop region (p < 0.05). These results suggest that maternal betaine supplementation during gestation enhances expression of mtDNA-encoded genes through D-loop DNA hypomethylation in the skeletal muscle of newborn piglets.

Aluminium induced oxidative stress results in decreased mitochondrial biogenesis via modulation of PGC-1α expression

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharma, Deep Raj; Sunkaria, Aditya; Wani, Willayat Yousuf

The present investigation was carried out to elucidate a possible molecular mechanism related to the effects of aluminium-induced oxidative stress on various mitochondrial respiratory complex subunits with special emphasis on the role of Peroxisome proliferator activated receptor gamma co-activator 1α (PGC-1α) and its downstream targets i.e. Nuclear respiratory factor-1(NRF-1), Nuclear respiratory factor-2(NRF-2) and Mitochondrial transcription factor A (Tfam) in mitochondrial biogenesis. Aluminium lactate (10 mg/kg b.wt./day) was administered intragastrically to rats for 12 weeks. After 12 weeks of exposure, we found an increase in ROS levels, mitochondrial DNA oxidation and decrease in citrate synthase activity in the Hippocampus (HC) andmore » Corpus striatum (CS) regions of rat brain. On the other hand, there was a decrease in the mRNA levels of the mitochondrial encoded subunits–NADH dehydrogenase (ND) subunits i.e. ND1, ND2, ND3, Cytochrome b (Cytb), Cytochrome oxidase (COX) subunits i.e. COX1, COX3, ATP synthase (ATPase) subunit 6 along with reduced expression of nuclear encoded subunits COX4, COX5A, COX5B of Electron transport chain (ETC). Besides, a decrease in mitochondrial DNA copy number and mitochondrial content in both regions of rat brain was observed. The PGC-1α was down-regulated in aluminium treated rats along with NRF-1, NRF-2 and Tfam, which act downstream from PGC-1α in aluminium treated rats. Electron microscopy results revealed a significant increase in the mitochondrial swelling, loss of cristae, chromatin condensation and decreases in mitochondrial number in case of aluminium treated rats as compared to control. So, PGC-1α seems to be a potent target for aluminium neurotoxicity, which makes it an almost ideal target to control or limit the damage that has been associated with the defective mitochondrial function seen in neurodegenerative diseases. - Highlights: • Aluminium decreases the mRNA levels of mitochondrial and nuclear encoded subunits. • It decreases the mtDNA copy number and mitochondrial content in rat brain. • It down-regulates the mRNA and protein levels of PGC-1α, NRF-1, NRF-2 and Tfam. • It also disturbs the mitochondrial or nuclear architecture of neurons. • Finally it also decreases mitochondrial number in HC and CS regions of rat brain.« less

Prevention of posterior capsular opacification through cyclooxygenase-2 inhibition

PubMed Central

Barden, Curtis A; Lu, Ping; Kusewitt, Donna F.; Colitz, Carmen M. H.

2007-01-01

Purpose To determine if cyclooxygenase-2 (COX-2) is upregulated when lens epithelial cells (LEC) in clinical samples of cataracts and posterior capsule opacification (PCO) undergo epithelial-mesenchymal transition (EMT)-like changes. We also wanted to learn if inhibition of the enzymatic activity of COX-2 could prevent PCO formation. Methods To ensure that EMT-like changes were occurring in LEC, real-time RT-PCR was used to examine expression of EMT markers. Clinical samples of canine cataracts and PCO were examined for COX-2 expression using immunohistochemistry, western blot analysis, and real-time RT-PCR. The COX-2 inhibitors, rofecoxib and celecoxib, were used in an ex vivo model of PCO formation, and the effects on cellular migration, proliferation, and apoptosis were analyzed using immunohistochemistry and western blots. Prostaglandin E2 (PGE2) expression was examined with ELISA. Results Markers of EMT, such as lumican, Snail, Slug, and COX-2 were expressed in LEC. In clinical samples of cataracts and PCO, there was overexpression of COX-2 protein and mRNA. Both rofecoxib and celecoxib were effective at inhibiting PCO formation in our ex vivo model. Prevention of PCO with the COX-2 inhibitors appeared to work through decreased migration and proliferation, and increased apoptosis. Neither of the drugs had a toxic effect on confluent LEC and appeared to inhibit PCO through their pharmacologic action. Synthesis of PGE2 was inhibiting in the capsules treated with the COX-2 inhibiting drugs. Conclusions Extracapsular phacoemulsification cataract surgery is the most common surgical procedure performed in human and veterinary ophthalmology. The most frequent postoperative complication is PCO. The LEC that remain adhered to the lens capsule undergo EMT-like changes, proliferate, and migrate across the posterior lens capsule causing opacities. We have shown that COX-2, a protein associated with EMT, is upregulated in canine cataracts and PCO. Inhibiting the enzymatic activity effectively prevented EMT of LEC in our ex vivo model of PCO through pharmacologic action, and not acute toxicity. These findings indicate that using COX-2 inhibitors in vivo may be an effective technique in preventing PCO. PMID:17563718

Reactive astrocyte COX2-PGE2 production inhibits oligodendrocyte maturation in neonatal white matter injury.

PubMed

Shiow, Lawrence R; Favrais, Geraldine; Schirmer, Lucas; Schang, Anne-Laure; Cipriani, Sara; Andres, Christian; Wright, Jaclyn N; Nobuta, Hiroko; Fleiss, Bobbi; Gressens, Pierre; Rowitch, David H

2017-12-01

Inflammation is a major risk factor for neonatal white matter injury (NWMI), which is associated with later development of cerebral palsy. Although recent studies have demonstrated maturation arrest of oligodendrocyte progenitor cells (OPCs) in NWMI, the identity of inflammatory mediators with direct effects on OPCs has been unclear. Here, we investigated downstream effects of pro-inflammatory IL-1β to induce cyclooxygenase-2 (COX2) and prostaglandin E2 (PGE2) production in white matter. First, we assessed COX2 expression in human fetal brain and term neonatal brain affected by hypoxic-ischemic encephalopathy (HIE). In the developing human brain, COX2 was expressed in radial glia, microglia, and endothelial cells. In human term neonatal HIE cases with subcortical WMI, COX2 was strongly induced in reactive astrocytes with "A2" reactivity. Next, we show that OPCs express the EP1 receptor for PGE2, and PGE2 acts directly on OPCs to block maturation in vitro. Pharmacologic blockade with EP1-specific inhibitors (ONO-8711, SC-51089), or genetic deficiency of EP1 attenuated effects of PGE2. In an IL-1β-induced model of NWMI, astrocytes also exhibit "A2" reactivity and induce COX2. Furthermore, in vivo inhibition of COX2 with Nimesulide rescues hypomyelination and behavioral impairment. These findings suggest that neonatal white matter astrocytes can develop "A2" reactivity that contributes to OPC maturation arrest in NWMI through induction of COX2-PGE2 signaling, a pathway that can be targeted for neonatal neuroprotection. © 2017 Wiley Periodicals, Inc.

Inhibition of cyclooxygenase (COX)-2 affects endothelial progenitor cell proliferation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Colleselli, Daniela; Bijuklic, Klaudija; Mosheimer, Birgit A.

2006-09-10

Growing evidence indicates that inducible cyclooxygenase-2 (COX-2) is involved in the pathogenesis of inflammatory disorders and various types of cancer. Endothelial progenitor cells recruited from the bone marrow have been shown to be involved in the formation of new vessels in malignancies and discussed for being a key point in tumour progression and metastasis. However, until now, nothing is known about an interaction between COX and endothelial progenitor cells (EPC). Expression of COX-1 and COX-2 was detected by semiquantitative RT-PCR and Western blot. Proliferation kinetics, cell cycle distribution and rate of apoptosis were analysed by MTT test and FACS analysis.more » Further analyses revealed an implication of Akt phosphorylation and caspase-3 activation. Both COX-1 and COX-2 expression can be found in bone-marrow-derived endothelial progenitor cells in vitro. COX-2 inhibition leads to a significant reduction in proliferation of endothelial progenitor cells by an increase in apoptosis and cell cycle arrest. COX-2 inhibition leads further to an increased cleavage of caspase-3 protein and inversely to inhibition of Akt activation. Highly proliferating endothelial progenitor cells can be targeted by selective COX-2 inhibition in vitro. These results indicate that upcoming therapy strategies in cancer patients targeting COX-2 may be effective in inhibiting tumour vasculogenesis as well as angiogenic processes.« less

Differential effects of selective cyclooxygenase (COX)-1 and COX-2 inhibitors on anorexic response and prostaglandin generation in various tissues induced by zymosan.

PubMed

Naoi, Kazuhisa; Kogure, Suguru; Saito, Masataka; Hamazaki, Tomohito; Watanabe, Shiro

2006-07-01

We have shown that anorexic response is induced by intraperitoneal injection of zymosan in mice, although the role of prostaglandins in this response is relatively unknown as compared with lipopolysaccharide (LPS)-induced anorexic response. Indomethacin (0.5 and 2.0 mg/kg), a non-selective cyclooxygenase (COX) inhibitor, as well as meloxicam (0.5 mg/kg), a selective COX-2 inhibitor, but not FR122047 (2.0 mg/kg), a selective COX-1 inhibitor, attenuated zymosan-induced anorexia. Zymosan injection elevated COX-2 expression in brain and liver but not in small intestine and colon. Meloxicam (0.5 mg/kg) and FR122047 treatment (2.0 mg/kg) similarly suppressed the generation of brain prostaglandin E(2) (PGE(2)) and peritoneal prostacyclin (PGI(2)) upon zymosan injection. PGE(2) generation in liver upon zymosan injection was suppressed by meloxicam (0.5 mg/kg) but not by FR122047 treatment (2.0 mg/kg). Our observations suggest that COX-2 plays an important role in zymosan-induced anorexia, which is a similar feature in LPS-induced anorexic response. However, non-selective inhibition by selective COX-1 and COX-2 inhibitors of brain PGE(2) generation upon zymosan injection does not support the role of COX-2 expressed in brain in zymosan-induced anorexic response. PGE(2) generation in liver may account for peripheral role of COX-2 in zymosan-induced anorexic response.

Integrated Cox's model for predicting survival time of glioblastoma multiforme.

PubMed

Ai, Zhibing; Li, Longti; Fu, Rui; Lu, Jing-Min; He, Jing-Dong; Li, Sen

2017-04-01

Glioblastoma multiforme is the most common primary brain tumor and is highly lethal. This study aims to figure out signatures for predicting the survival time of patients with glioblastoma multiforme. Clinical information, messenger RNA expression, microRNA expression, and single-nucleotide polymorphism array data of patients with glioblastoma multiforme were retrieved from The Cancer Genome Atlas. Patients were separated into two groups by using 1 year as a cutoff, and a logistic regression model was used to figure out any variables that can predict whether the patient was able to live longer than 1 year. Furthermore, Cox's model was used to find out features that were correlated with the survival time. Finally, a Cox model integrated the significant clinical variables, messenger RNA expression, microRNA expression, and single-nucleotide polymorphism was built. Although the classification method failed, signatures of clinical features, messenger RNA expression levels, and microRNA expression levels were figured out by using Cox's model. However, no single-nucleotide polymorphisms related to prognosis were found. The selected clinical features were age at initial diagnosis, Karnofsky score, and race, all of which had been suggested to correlate with survival time. Both of the two significant microRNAs, microRNA-221 and microRNA-222, were targeted to p27 Kip1 protein, which implied the important role of p27 Kip1 on the prognosis of glioblastoma multiforme patients. Our results suggested that survival modeling was more suitable than classification to figure out prognostic biomarkers for patients with glioblastoma multiforme. An integrated model containing clinical features, messenger RNA levels, and microRNA expression levels was built, which has the potential to be used in clinics and thus to improve the survival status of glioblastoma multiforme patients.

Genotoxic stress induces Sca-1 expressing metastatic mammary cancer cells.

PubMed

Gong, Jianlin; Lang, Benjamin J; Weng, Desheng; Eguchi, Takanori; Murshid, Ayesha; Borges, Thiago J; Doshi, Sachin; Song, Baizheng; Stevenson, Mary Ann; Calderwood, Stuart K

2018-05-08

We describe a cell damage-induced phenotype in mammary carcinoma cells involving acquisition of enhanced migratory and metastatic properties. Induction of this state by radiation required increased activity of the Ptgs2 gene product cyclooxygenase 2 (Cox2), secretion of its bioactive lipid product prostaglandin E2 (PGE2) and the activity of the PGE2 receptor EP4. Although largely transient, decaying to low levels in a few days to a week, this phenotype was cumulative with damage and levels of cell markers Sca-1 and ALDH1 increased with treatment dose. The Sca-1 + , metastatic phenotype was inhibited by both Cox2 inhibitors and PGE2 receptor antagonists suggesting novel approaches to radiosensitization. Molecular Oncology (2018) © 2018 The Authors. Published by FEBS Press and John Wiley & Sons Ltd.

Monitoring tissue inflammation and responses to drug treatments in early stages of mice bone fracture using 50 MHz ultrasound

PubMed Central

Chen, Yen-Chu; Lin, Yi-Hsun; Wang, Shyh-Hau; Lin, Shih-Ping; Shung, K. Kirk; Wu, Chia-Ching

2014-01-01

Bone fracture induces moderate inflammatory responses that are regulated by cyclooxygenase-2 (COX-2) or 5-lipoxygenase (5-LO) for initiating tissue repair and bone formation. Only a handful of non-invasive techniques focus on monitoring acute inflammation of injured bone currently exists. In the current study, we monitored in vivo inflammation levels during the initial 2 weeks of the inflammatory stage after mouse bone fracture utilizing 50 MHz ultrasound. The acquired ultrasonic images were correlated well with histological examinations. After the bone fracture in the tibia, dynamic changes in the soft tissue at the medial-posterior compartment near the fracture site were monitored by ultrasound on the days of 0, 2, 4, 7, and 14. The corresponding echogenicity increased on the 2nd, 4th, and 7th day, and subsequently declined to basal levels after the 14th day. An increase of cell death was identified by the positive staining of deoxynucleotidyl transferase dUTP nick end-labeling (TUNEL) assay and was consistent with ultrasound measurements. The increases of both COX-2 and Leukotriene B4 receptor 1 (BLT1, 5- LO-relative receptor), which are regulators for tissue inflammation, in the immunohistochemistry staining revealed their involvement in bone fracture injury. Monitoring the inflammatory response to various non-steroidal anti-inflammatory drugs (NSAIDs) treatments was investigated by treating injured mice with a daily oral intake of aspirin (Asp), indomethacin (IND), and a selective COX-2 inhibitor (SC-236). The Asp treatment significantly reduced fracture-increased echogenicity (hyperechogenicity, p < 0.05) in ultrasound images as well as inhibited cell death, and expression of COX-2 and BLT1. In contrast, treatment with IND or SC-236 did not reduce the hyperechogenicity, as confirmed by cell death (TUNEL) and expression levels of COX-2 or BLT1. Taken together, the current study reports the feasibility of a noninvasive ultrasound method capable of monitoring post-fracture tissue inflammation that positively correlates with histological findings. Results of this study also suggest that this approach may be further applied to elucidate the underlying mechanisms of inflammatory processes and to develop therapeutic strategies for facilitating fracture healing. PMID:23871514

Role of spinal p38α and β MAPK in inflammatory hyperalgesia and spinal COX-2 expression

PubMed Central

Fitzsimmons, Bethany L.; Zattoni, Michela; Svensson, Camilla I.; Steinauer, Joanne; Hua, Xiao-Ying; Yaksh, Tony L.

2010-01-01

Pharmacological studies indicate that spinal p38 MAPK plays a role in the development of hyperalgesia. We investigated whether either the spinal isoform p38α or p38β is involved in peripheral inflammation-evoked pain state and increased expression of spinal COX-2. Using intrathecal antisense oligonucleotides, we show that hyperalgesia is prevented by downregulation of p38β but not p38α, while increases in spinal COX-2 protein expression at eight hours is mediated by both p38α and β isoforms. These data suggest that early activation of spinal p38β isoform may affect acute facilitatory processing, and both p38β and α isforms mediate temporally delayed upregulation of spinal COX-2. PMID:20134354

Changes in gene expression linked to methamphetamine-induced dopaminergic neurotoxicity.

PubMed

Xie, Tao; Tong, Liqiong; Barrett, Tanya; Yuan, Jie; Hatzidimitriou, George; McCann, Una D; Becker, Kevin G; Donovan, David M; Ricaurte, George A

2002-01-01

The purpose of these studies was to examine the role of gene expression in methamphetamine (METH)-induced dopamine (DA) neurotoxicity. First, the effects of the mRNA synthesis inhibitor, actinomycin-D, and the protein synthesis inhibitor, cycloheximide, were examined. Both agents afforded complete protection against METH-induced DA neurotoxicity and did so independently of effects on core temperature, DA transporter function, or METH brain levels, suggesting that gene transcription and mRNA translation play a role in METH neurotoxicity. Next, microarray technology, in combination with an experimental approach designed to facilitate recognition of relevant gene expression patterns, was used to identify gene products linked to METH-induced DA neurotoxicity. This led to the identification of several genes in the ventral midbrain associated with the neurotoxic process, including genes for energy metabolism [cytochrome c oxidase subunit 1 (COX1), reduced nicotinamide adenine dinucleotide ubiquinone oxidoreductase chain 2, and phosphoglycerate mutase B], ion regulation (members of sodium/hydrogen exchanger and sodium/bile acid cotransporter family), signal transduction (adenylyl cyclase III), and cell differentiation and degeneration (N-myc downstream-regulated gene 3 and tau protein). Of these differentially expressed genes, we elected to further examine the increase in COX1 expression, because of data implicating energy utilization in METH neurotoxicity and the known role of COX1 in energy metabolism. On the basis of time course studies, Northern blot analyses, in situ hybridization results, and temperature studies, we now report that increased COX1 expression in the ventral midbrain is linked to METH-induced DA neuronal injury. The precise role of COX1 and other genes in METH neurotoxicity remains to be elucidated.

Global Gene Expression Analysis of Canine Osteosarcoma Stem Cells Reveals a Novel Role for COX-2 in Tumour Initiation

PubMed Central

Pang, Lisa Y.; Gatenby, Emma L.; Kamida, Ayako; Whitelaw, Bruce A.; Hupp, Ted R.; Argyle, David J.

2014-01-01

Osteosarcoma is the most common primary bone tumour of both children and dogs. It is an aggressive tumour in both species with a rapid clinical course leading ultimately to metastasis. In dogs and children distant metastasis occurs in >80% of individuals treated by surgery alone. Both canine and human osteosarcoma has been shown to contain a sub-population of cancer stem cells (CSCs), which may drive tumour growth, recurrence and metastasis, suggesting that naturally occurring canine osteosarcoma could act as a preclinical model for the human disease. Here we report the successful isolation of CSCs from primary canine osteosarcoma, as well as established cell lines. We show that these cells can form tumourspheres, and demonstrate relative resistance to chemotherapy. We demonstrate similar results for the human osteosarcma cell lines, U2OS and SAOS2. Utilizing the Affymetrix canine microarray, we are able to definitively show that there are significant differences in global gene expression profiles of isolated osteosarcoma stem cells and the daughter adherent cells. We identified 13,221 significant differences (p = 0.05), and significantly, COX-2 was expressed 141-fold more in CSC spheres than daughter adherent cells. To study the role of COX-2 expression in CSCs we utilized the COX-2 inhibitors meloxicam and mavacoxib. We found that COX-2 inhibition had no effect on CSC growth, or resistance to chemotherapy. However inhibition of COX-2 in daughter cells prevented sphere formation, indicating a potential significant role for COX-2 in tumour initiation. PMID:24416158

Global gene expression analysis of canine osteosarcoma stem cells reveals a novel role for COX-2 in tumour initiation.

PubMed

Pang, Lisa Y; Gatenby, Emma L; Kamida, Ayako; Whitelaw, Bruce A; Hupp, Ted R; Argyle, David J

2014-01-01

Osteosarcoma is the most common primary bone tumour of both children and dogs. It is an aggressive tumour in both species with a rapid clinical course leading ultimately to metastasis. In dogs and children distant metastasis occurs in >80% of individuals treated by surgery alone. Both canine and human osteosarcoma has been shown to contain a sub-population of cancer stem cells (CSCs), which may drive tumour growth, recurrence and metastasis, suggesting that naturally occurring canine osteosarcoma could act as a preclinical model for the human disease. Here we report the successful isolation of CSCs from primary canine osteosarcoma, as well as established cell lines. We show that these cells can form tumourspheres, and demonstrate relative resistance to chemotherapy. We demonstrate similar results for the human osteosarcma cell lines, U2OS and SAOS2. Utilizing the Affymetrix canine microarray, we are able to definitively show that there are significant differences in global gene expression profiles of isolated osteosarcoma stem cells and the daughter adherent cells. We identified 13,221 significant differences (p = 0.05), and significantly, COX-2 was expressed 141-fold more in CSC spheres than daughter adherent cells. To study the role of COX-2 expression in CSCs we utilized the COX-2 inhibitors meloxicam and mavacoxib. We found that COX-2 inhibition had no effect on CSC growth, or resistance to chemotherapy. However inhibition of COX-2 in daughter cells prevented sphere formation, indicating a potential significant role for COX-2 in tumour initiation.

Berberine-induced AMPK activation inhibits the metastatic potential of melanoma cells via reduction of ERK activity and COX-2 protein expression.

PubMed

Kim, Hak-Su; Kim, Myung-Jin; Kim, Eun Ju; Yang, Young; Lee, Myeong-Sok; Lim, Jong-Seok

2012-02-01

Berberine is clinically important natural isoquinoline alkaloid that affects various biological functions, such as cell proliferation, migration and survival. The activation of AMP-activated protein kinase (AMPK) regulates tumor cell migration. However, the specific role of AMPK on the metastatic potential of cancer cells remains largely unknown. The present study investigated whether berberine induces AMPK activation and whether this induction directly affects mouse melanoma cell migration, adhesion and invasion. Berberine strongly increased AMPK phosphorylation via reactive oxygen species (ROS) production. 5-Aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR), a well-known AMPK activator, also inhibited tumor cell adhesion and invasion and reduced the expression of epithelial to mesenchymal transition (EMT)-related genes. Knockdown of AMPKα subunits using siRNAs significantly abated the berberine-induced inhibition of tumor cell invasion. Furthermore, berberine inhibited the metastatic potential of melanoma cells through a decrease in ERK activity and protein levels of cyclooxygenase-2 (COX-2) by a berberine-induced AMPK activation. These data were confirmed using specific MEK inhibitor, PD98059, and a COX-2 inhibitor, celecoxib. Berberine- and AICAR-treated groups demonstrated significantly decreased lung metastases in the pulmonary metastasis model in vivo. Treatment with berberine also decreased the metastatic potential of A375 human melanoma cells. Collectively, our results suggest that berberine-induced AMPK activation inhibits the metastatic potential of tumor cells through a reduction in the activity of the ERK signaling pathway and COX-2 protein levels. Copyright © 2011 Elsevier Inc. All rights reserved.

Flavocoxid, a dual inhibitor of COX-2 and 5-LOX of natural origin, attenuates the inflammatory response and protects mice from sepsis

PubMed Central

2012-01-01

Introduction Cecal ligation and puncture (CLP) is an inflammatory condition that leads to multisystemic organ failure. Flavocoxid, a dual inhibitor of cyclooxygenase (COX-2) and 5-lipoxygenase (5-LOX), has been shown in vitro to possess antiinflammatory activity in lipopolysaccharide (LPS)-stimulated rat macrophages by reducing nuclear factor (NF)-κB activity and COX-2, 5-LOX and inducible nitric oxide synthase (iNOS) expression. The aim of this study was to evaluate the effects of flavocoxid in a murine model of CLP-induced polymicrobial sepsis. Methods C57BL/6J mice were subjected to CLP or sham operation. In a first set of experiments, an intraperitoneal injection of flavocoxid (20 mg/kg) or vehicle was administered 1 hour after surgery and repeated every 12 hours. Survival rate was monitored every 24 hours throughout 120 hours. Furthermore, additional groups of sham and CLP mice were killed 18 hours after surgical procedures for blood-sample collection and the lung and liver were collected for biomolecular, biochemical and histopathologic studies. Results COX-2, 5-LOX, tumor necrosis factor-α (TNF-α), interleukin (IL)-6, IL-10, extracellular-regulated-kinase 1/2 (ERK), JunN-terminal kinase (JNK), NF-κB, and β-arrestin 2 protein expression were evaluated in lung and liver with Western blot analysis. In addition, leukotriene B4 (LTB4), prostaglandin E2 (PGE2), cytokines, and lipoxin A4 serum content were measured with an enzyme-linked immunosorbent assay (ELISA). Flavocoxid administration improved survival, reduced the expression of NF-κB, COX-2, 5-LOX, TNF-α and IL-6 and increased IL-10 production. Moreover, flavocoxid inhibited the mitogen-activated protein kinases (MAPKs) pathway, preserved β-arrestin 2 expression, reduced blood LTB4, PGE2, TNF-α and IL-6, and increased IL-10 and lipoxin A4 serum levels. The treatment with flavocoxid also protected against the histologic damage induced by CLP and reduced the myeloperoxidase (MPO) activity in the lung and liver. Conclusions Flavocoxid protects mice from sepsis, suggesting that this dual inhibitor may represent a promising approach in such a life-threatening condition. PMID:22356547

Flavocoxid, a dual inhibitor of COX-2 and 5-LOX of natural origin, attenuates the inflammatory response and protects mice from sepsis.

PubMed

Bitto, Alessandra; Minutoli, Letteria; David, Antonio; Irrera, Natasha; Rinaldi, Mariagrazia; Venuti, Francesco S; Squadrito, Francesco; Altavilla, Domenica

2012-02-22

Cecal ligation and puncture (CLP) is an inflammatory condition that leads to multisystemic organ failure. Flavocoxid, a dual inhibitor of cyclooxygenase (COX-2) and 5-lipoxygenase (5-LOX), has been shown in vitro to possess antiinflammatory activity in lipopolysaccharide (LPS)-stimulated rat macrophages by reducing nuclear factor (NF)-κB activity and COX-2, 5-LOX and inducible nitric oxide synthase (iNOS) expression. The aim of this study was to evaluate the effects of flavocoxid in a murine model of CLP-induced polymicrobial sepsis. C57BL/6J mice were subjected to CLP or sham operation. In a first set of experiments, an intraperitoneal injection of flavocoxid (20 mg/kg) or vehicle was administered 1 hour after surgery and repeated every 12 hours. Survival rate was monitored every 24 hours throughout 120 hours. Furthermore, additional groups of sham and CLP mice were killed 18 hours after surgical procedures for blood-sample collection and the lung and liver were collected for biomolecular, biochemical and histopathologic studies. COX-2, 5-LOX, tumor necrosis factor-α (TNF-α), interleukin (IL)-6, IL-10, extracellular-regulated-kinase 1/2 (ERK), JunN-terminal kinase (JNK), NF-κB, and β-arrestin 2 protein expression were evaluated in lung and liver with Western blot analysis. In addition, leukotriene B4 (LTB4), prostaglandin E2 (PGE2), cytokines, and lipoxin A4 serum content were measured with an enzyme-linked immunosorbent assay (ELISA). Flavocoxid administration improved survival, reduced the expression of NF-κB, COX-2, 5-LOX, TNF-α and IL-6 and increased IL-10 production. Moreover, flavocoxid inhibited the mitogen-activated protein kinases (MAPKs) pathway, preserved β-arrestin 2 expression, reduced blood LTB4, PGE2, TNF-α and IL-6, and increased IL-10 and lipoxin A4 serum levels. The treatment with flavocoxid also protected against the histologic damage induced by CLP and reduced the myeloperoxidase (MPO) activity in the lung and liver. Flavocoxid protects mice from sepsis, suggesting that this dual inhibitor may represent a promising approach in such a life-threatening condition.

Impact of COX2 genotype, ER status and body constitution on risk of early events in different treatment groups of breast cancer patients.

PubMed

Markkula, Andrea; Simonsson, Maria; Rosendahl, Ann H; Gaber, Alexander; Ingvar, Christian; Rose, Carsten; Jernström, Helena

2014-10-15

The COX2 rs5277 (306G>C) polymorphism has been associated with inflammation-associated cancers. In breast cancer, tumor COX-2 expression has been associated with increased estrogen levels in estrogen receptor (ER)-positive and activated Akt-pathway in ER-negative tumors. Our study investigated the impact of COX2 genotypes on early breast cancer events and treatment response in relation to tumor ER status and body constitution. In Sweden, between 2002 and 2008, 634 primary breast cancer patients, aged 25-99 years, were included. Disease-free survival was assessed for 570 rs5277-genotyped patients. Body measurements and questionnaires were obtained preoperatively. Clinical data, patient- and tumor-characteristics were obtained from questionnaires, patients' charts, population registries and pathology reports. Minor allele(C) frequency was 16.1%. Genotype was not linked to COX-2 tumor expression. Median follow-up was 5.1 years. G/G genotype was not associated with early events in patients with ER-positive tumors, adjusted HR 0.77 (0.46-1.29), but conferred an over 4-fold increased risk in patients with ER-negative tumors, adjusted HR 4.41 (1.21-16.02)(p(interaction) = 0.015). Chemotherapy-treated G/G-carriers with a breast volume ≥ 850 ml had an increased risk of early events irrespective of ER status, adjusted HR 8.99 (1.14-70.89). Endocrine-treated C-allele carriers with ER-positive tumors and a breast volume ≥ 850 ml had increased risk of early events, adjusted HR 2.30 (1.12-4.75). COX2 genotype, body constitution and ER status had a combined effect on the risk of early events and treatment response. The high risk for early events in certain subgroups of patients suggests that COX2 genotype in combination with body measurements may identify patients in need of more personalized treatment. © 2014 The Authors. Published by Wiley Periodicals, Inc. on behalf of UICC.

COX-2 Elevates Oncogenic miR-526b in Breast Cancer by EP4 Activation.

PubMed

Majumder, Mousumi; Landman, Erin; Liu, Ling; Hess, David; Lala, Peeyush K

2015-06-01

MicroRNAs (miRs) are small regulatory molecules emerging as potential biomarkers in cancer. Previously, it was shown that COX-2 expression promotes breast cancer progression via multiple mechanisms, including induction of stem-like cells (SLC), owing to activation of the prostaglandin E2 receptor EP4 (PTGER4). COX-2 overexpression also upregulated microRNA-526b (miR-526b), in association with aggressive phenotype. Here, the functional roles of miR-526b in breast cancer and the mechanistic role of EP4 signaling in miR-526b upregulation were examined. A positive correlation was noted between miR-526b and COX-2 mRNA expression in COX-2 disparate breast cancer cell lines. Stable overexpression of miR-526b in poorly metastatic MCF7 and SKBR3 cell lines resulted in increased cellular migration, invasion, EMT phenotype and enhanced tumorsphere formation in vitro, and lung colony formation in vivo in immunodeficient mice. Conversely, knockdown of miR-526b in aggressive MCF7-COX-2 and SKBR3-COX-2 cells reduced oncogenic functions and reversed the EMT phenotype, in vitro. Furthermore, it was determined that miR-526b expression is dependent on EP4 receptor activity and downstream PI3K-AKT and cyclic AMP (cAMP) signaling pathways. PI3K-AKT inhibitors blocked EP4 agonist-mediated miR-526b upregulation and tumorsphere formation in MCF7 and SKBR3 cells. NF-κB inhibitor abrogates EP agonist-stimulated miRNA expression in MCF7 and T47D cells, indicating that the NF-κB pathway is also involved in miR-526b regulation. In addition, inhibition of COX-2, EP4, PI3K, and PKA in COX-2-overexpressing cells downregulated miR-526b and its functions in vitro. Finally, miR-526b expression was significantly higher in cancerous than in noncancerous breast tissues and associated with reduced patient survival. In conclusion, miR-526b promotes breast cancer progression, SLC-phenotype through EP4-mediated signaling, and correlates with breast cancer patient survival. This study presents novel findings that miRNA 526b is a COX-2 upregulated, oncogenic miRNA promoting SLCs, the expression of which follows EP4 receptor-mediated signaling, and is a promising biomarker for monitoring and personalizing breast cancer therapy. ©2015 American Association for Cancer Research.

Cancer/stroma interplay via cyclooxygenase-2 and indoleamine 2,3-dioxygenase promotes breast cancer progression.

PubMed

Chen, Jing-Yi; Li, Chien-Feng; Kuo, Cheng-Chin; Tsai, Kelvin K; Hou, Ming-Feng; Hung, Wen-Chun

2014-07-25

Expression of indoleamine 2,3-dioxygenase (IDO) in primary breast cancer increases tumor growth and metastasis. However, the clinical significance of stromal IDO and the regulation of stromal IDO are unclear. Metabolomics and enzyme-linked immunosorbent assay (ELISA) were used to study the effect of cyclooxygenase-2 (COX-2)-overexpressing breast cancer cells on IDO expression in co-cultured human breast fibroblasts. Biochemical inhibitors and short-hairpin RNA (shRNA) were used to clarify how prostaglandin E2 (PGE2) upregulates IDO expression. Associations of stromal IDO with clinicopathologic parameters were tested in tumor specimens. An orthotopic animal model was used to examine the effect of COX-2 and IDO inhibitors on tumor growth. Kynurenine, the metabolite generated by IDO, increases in the supernatant of fibroblasts co-cultured with COX-2-overexpressing breast cancer cells. PGE2 released by cancer cells upregulates IDO expression in fibroblasts through an EP4/signal transducer and activator of transcription 3 (STAT3)-dependent pathway. Conversely, fibroblast-secreted kynurenine promotes the formation of the E-cadherin/Aryl hydrocarbon receptor (AhR)/S-phase kinase-associated protein 2 (Skp2) complex, resulting in degradation of E-cadherin to increase breast cancer invasiveness. The enhancement of motility of breast cancer cells induced by co-culture with fibroblasts is suppressed by the IDO inhibitor 1-methyl-tryptophan. Pathological analysis demonstrates that upregulation of stromal IDO is a poor prognosis factor and is associated with of COX-2 overexpression. Co-expression of cancer COX-2 and stromal IDO predicts a worse disease-free and metastasis-free survival. Finally, COX-2 and IDO inhibitors inhibit tumor growth in vivo. Integration of metabolomics and molecular and pathological approaches reveals the interplay between cancer and stroma via COX-2, and IDO promotes tumor progression and predicts poor patient survival.

Manipulation of sinapine, choline and betaine accumulation in Arabidopsis seed: towards improving the nutritional value of the meal and enhancing the seedling performance under environmental stresses in oilseed crops.

PubMed

Huang, Jun; Rozwadowski, Kevin; Bhinu, V S; Schäfer, Ulrike; Hannoufa, Abdelali

2008-07-01

Sinapoylcholine (sinapine) is the most abundant antinutritional phenolic compound in cruciferous seeds. The quaternary ammonium compounds, choline, betaine and N,N-dimethylglycine, reside along a biosynthetic pathway linked to the synthesis of membrane phospholipids and neurotransmitters with various biological functions. In chicken, choline intake is required for optimal egg-laying performance and a choline supplement in diet is positively correlated with weight gains. A key step in sinapine biosynthesis is catalyzed by sinapoylglucose: choline sinapoyltransferase (SCT; EC 2.3.1.91) to form an ester linkage with sinapoylglucose and choline. The objective of this work was to reduce the sinapine content and simultaneously enhance free choline levels in cruciferous seeds. We report here the characterization of an Arabidopsis T-DNA insertion mutant lacking SCT activity in the seed. The sct mutant seeds contain less than 1% of sinapine and a more than 2-fold increase in free choline compared with wild type. We further expressed a choline oxidase (COX; EC 1.1.3.17) gene from Arthrobacter pascens in the Arabidopsis sct mutant and wild-type background using a napin gene promoter to convert free choline into betaine, an effective stress-alleviating compound in plants. Betaine was not detected in WT or sct mutant seeds. The sct+COX seeds contain nearly 2-fold greater levels of betaine relative to WT+COX seeds, demonstrating a positive correlation between endogenous choline and betaine production. In contrast, stable comparable levels of free choline were detected between sct+COX and WT+COX plants suggesting choline homeostasis likely prevent high levels of betaine production in the seed of transgenic COX plants.

ZN2+ INDUCES COX-2 EXPRESSION THROUGH DOWNREGULATION OF LIPID PHOSPHATASE PTEN

EPA Science Inventory

Zn2+ Induces COX-2 Expression through Downregulation of Lipid Phosphatase PTEN
Weidong Wu*, James M. Samet, Philip A. Bromberg*?, Young E. Whang?, and Lee M. Graves* ?
*CEMALB, ?Department of Medicine, and ?Department of Pharmacology, UNC-Chapel Hill, NC27599; Human Studie...

Role of cyclooxygenase isoforms in the altered excitatory motor pathways of human colon with diverticular disease.

PubMed

Fornai, M; Colucci, R; Antonioli, L; Ippolito, C; Segnani, C; Buccianti, P; Marioni, A; Chiarugi, M; Villanacci, V; Bassotti, G; Blandizzi, C; Bernardini, N

2014-08-01

The COX isoforms (COX-1, COX-2) regulate human gut motility, although their role under pathological conditions remains unclear. This study examines the effects of COX inhibitors on excitatory motility in colonic tissue from patients with diverticular disease (DD). Longitudinal muscle preparations, from patients with DD or uncomplicated cancer (controls), were set up in organ baths and connected to isotonic transducers. Indomethacin (COX-1/COX-2 inhibitor), SC-560 (COX-1 inhibitor) or DFU (COX-2 inhibitor) were assayed on electrically evoked, neurogenic, cholinergic and tachykininergic contractions, or carbachol- and substance P (SP)-induced myogenic contractions. Distribution and expression of COX isoforms in the neuromuscular compartment were assessed by RT-PCR, Western blot and immunohistochemical analysis. In control preparations, neurogenic cholinergic contractions were enhanced by COX inhibitors, whereas tachykininergic responses were blunted. Carbachol-evoked contractions were increased by indomethacin or SC-560, but not DFU, whereas all inhibitors reduced SP-induced motor responses. In preparations from DD patients, COX inhibitors did not affect electrically evoked cholinergic contractions. Both indomethacin and DFU, but not SC-560, decreased tachykininergic responses. COX inhibitors did not modify carbachol-evoked motor responses, whereas they counteracted SP-induced contractions. COX-1 expression was decreased in myenteric neurons, whereas COX-2 was enhanced in glial cells and smooth muscle. In control colon, COX-1 and COX-2 down-regulate cholinergic motility, whereas both isoforms enhance tachykininergic motor activity. In the presence of DD, there is a loss of modulation by both COX isoforms on the cholinergic system, whereas COX-2 displays an enhanced facilitatory control on tachykininergic contractile activity. © 2014 The British Pharmacological Society.

Role of cyclooxygenase isoforms in the altered excitatory motor pathways of human colon with diverticular disease

PubMed Central

Fornai, M; Colucci, R; Antonioli, L; Ippolito, C; Segnani, C; Buccianti, P; Marioni, A; Chiarugi, M; Villanacci, V; Bassotti, G; Blandizzi, C; Bernardini, N

2014-01-01

BACKGROUND AND PURPOSE The COX isoforms (COX-1, COX-2) regulate human gut motility, although their role under pathological conditions remains unclear. This study examines the effects of COX inhibitors on excitatory motility in colonic tissue from patients with diverticular disease (DD). EXPERIMENTAL APPROACH Longitudinal muscle preparations, from patients with DD or uncomplicated cancer (controls), were set up in organ baths and connected to isotonic transducers. Indomethacin (COX-1/COX-2 inhibitor), SC-560 (COX-1 inhibitor) or DFU (COX-2 inhibitor) were assayed on electrically evoked, neurogenic, cholinergic and tachykininergic contractions, or carbachol- and substance P (SP)-induced myogenic contractions. Distribution and expression of COX isoforms in the neuromuscular compartment were assessed by RT-PCR, Western blot and immunohistochemical analysis. KEY RESULTS In control preparations, neurogenic cholinergic contractions were enhanced by COX inhibitors, whereas tachykininergic responses were blunted. Carbachol-evoked contractions were increased by indomethacin or SC-560, but not DFU, whereas all inhibitors reduced SP-induced motor responses. In preparations from DD patients, COX inhibitors did not affect electrically evoked cholinergic contractions. Both indomethacin and DFU, but not SC-560, decreased tachykininergic responses. COX inhibitors did not modify carbachol-evoked motor responses, whereas they counteracted SP-induced contractions. COX-1 expression was decreased in myenteric neurons, whereas COX-2 was enhanced in glial cells and smooth muscle. CONCLUSIONS AND IMPLICATIONS In control colon, COX-1 and COX-2 down-regulate cholinergic motility, whereas both isoforms enhance tachykininergic motor activity. In the presence of DD, there is a loss of modulation by both COX isoforms on the cholinergic system, whereas COX-2 displays an enhanced facilitatory control on tachykininergic contractile activity. PMID:24758697

Protective effect of Holothurian intestine against indomethacin induced gastric mucosal damage in rats

NASA Astrophysics Data System (ADS)

Li, Xiaoyu; Qiao, Xuejing; Zhang, Cuiping; Gao, Hua; Niu, Qinghui; Wu, Tong; Zhang, Qi; Tian, Zibin

2017-06-01

Our study aimed to investigate the protective effects of Holothurian intestines (HI) on NSAIDs-induced gastric mucosal damage and the possible mechanism. At first, 60 male Wistar rats were induced of gastric lesions with indomethacin (IDM, 30 mg kg-1). The rats were pretreated for 15 consecutive days with saline, sucralfate, or HI (0.4 g kg-1d-1, 0.8 g kg-1d-1 and 1.6 g kg-1d-1) prior to IDM treatment, followed by evaluations of macroscopic damage and microscopic features; and investigation of the levels of inflammatory cytokines, oxidative stress parameters, gastric mucosal prostaglandin E2 (PGE2) and total hexosamine in tissues. The expression of COX-1 and COX-2 mRNA in the gastric tissue were determined by quantitative polymerase chain reaction (qPCR). Pathological gastric ulcer indexes, levels of pro-inflammatory cytokines (IL-1β, IL-17, TNF-α) and lipid peroxidation were significantly decreased in HI-treated groups, whereas the levels of protective factors (TGF-β, GSH, SOD activity and PGE2) were significantly elevated especially in the group with HI 1.6 g kg-1d-1 ( P < 0.05). Furthermore, the expression of COX-2 mRNA decreased significantly in HI groups ( P < 0.05). The study investigates that holothurian intestines may act as a kind of marine medicine which have protective effect on IDM-induced gastric ulcer, which could be a dietary preventive agent for the prevention of gastric damage.

Valsartan decreases platelet activity and arterial thrombotic events in elderly patients with hypertension.

PubMed

Wu, Fang; Wang, Hong-Yan; Cai, Fan; Wang, Ling-Jie; Zhang, Feng-Ru; Chen, Xiao-Nan; Yang, Qian; Jiang, Meng-Hui; Wang, Xue-Feng; Shen, Wei-Feng

2015-01-20

Angiotensin type 1 receptor (AT 1 R) antagonists are extensively used for blood pressure control in elderly patients with hypertension. This study aimed to investigate the inhibitory effects of AT 1 R antagonist valsartan on platelet aggregation and the occurrence of cardio-cerebral thrombotic events in elderly patients with hypertension. Two-hundred and ten patients with hypertension and aged > 60 years were randomized to valsartan (n = 140) or amlodipine (n = 70) on admission. The primary endpoint was platelet aggregation rate (PAR) induced by arachidonic acid at discharge, and the secondary endpoint was the rate of thrombotic events including brain infarction and myocardial infarction during follow-up. Human aortic endothelial cells (HAECs) were stimulated by angiotensin II (Ang II, 100 nmol/L) with or without pretreatment of valsartan (100 nmol/L), and relative expression of cyclooxygenase-2 (COX-2) and thromboxane B 2 (TXB 2 ) and both p38 mitogen-activated protein kinase (p38MAPK) and nuclear factor-kB (NF-kB) activities were assessed. Statistical analyses were performed by GraphPad Prism 5.0 software (GraphPad Software, Inc., California, USA). PAR was lower after treatment with valsartan (11.49 ± 0.69% vs. 18.71 ± 2.47%, P < 0.001), associated with more reduced plasma levels of COX-2 (76.94 ± 7.07 U/L vs. 116.4 ± 15.89 U/L, P < 0.001) and TXB 2 (1667 ± 56.50 pg/ml vs. 2207 ± 180.20 pg/ml) (all P < 0.001). Plasma COX-2 and TXB 2 levels correlated significantly with PAR in overall patients (r = 0.109, P < 0.001). During follow-up (median, 18 months), there was a significantly lower thrombotic event rate in patients treated with valsartan (14.3% vs. 32.8%, P = 0.002). Relative expression of COX-2 and secretion of TXB 2 with concordant phosphorylation of p38MAPK and NF-kB were increased in HAECs when stimulated by Ang II (100 nmol/L) but were significantly decreased by valsartan pretreatment (100 nmol/L). AT 1 R antagonist valsartan decreases platelet activity by attenuating COX-2/TXA 2 expression through p38MAPK and NF-kB pathways and reduces the occurrence of cardio-cerebral thrombotic events in elderly patients with hypertension.

The role of p38 in mitochondrial respiration in male and female mice.

PubMed

Ju, Xiaohua; Wen, Yi; Metzger, Daniel; Jung, Marianna

2013-06-07

p38 is a mitogen-activated protein kinase and mediates cell growth, cell differentiation, and synaptic plasticity. The aim of this study is to determine the extent to which p38 plays a role in maintaining mitochondrial respiration in male and female mice under a normal condition. To achieve this aim, we have generated transgenic mice that lack p38 in cerebellar Purkinje neurons by crossing Pcp2 (Purkinje cell protein 2)-Cre mice with p38(loxP/loxP) mice. Mitochondria from cerebellum were then isolated from the transgenic and wild-type mice to measure mitochondrial respiration using XF24 respirometer. The mRNA and protein expression of cytochrome c oxidase (COX) in cerebellum were also measured using RT-PCR and immunoblot methods. Separately, HT22 cells were used to determine the involvement of 17β-estradiol (E2) and COX in mitochondrial respiration. The genetic knockout of p38 in Purkinje neurons suppressed the mitochondrial respiration only in male mice and increased COX expression only in female mice. The inhibition of COX by sodium azide (SA) sharply suppressed mitochondrial respiration of HT22 cells in a manner that was protected by E2. These data suggest that p38 is required for the mitochondrial respiration of male mice. When p38 is below a normal level, females may maintain mitochondrial respiration through COX up-regulation. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Inhibitory effect of rape pollen supercritical CO2 fluid extract against testosterone-induced benign prostatic hyperplasia in rats

PubMed Central

YANG, BI-CHENG; JIN, LI-LI; YANG, YI-FANG; LI, KUN; PENG, DAN-MING

2014-01-01

Benign prostatic hyperplasia (BPH) can lead to lower urinary tract symptoms. Rape pollen is an apicultural product that is composed of nutritionally valuable and biologically active substances. The aim of the present study was to investigate the protective effect of rape pollen supercritical CO2 fluid extract (SFE-CO2) in BPH development using a testosterone-induced BPH rat model. BPH was induced in the experimental groups by daily subcutaneous injections of testosterone for a period of 30 days. Rape pollen SFE-CO2 was administered daily by oral gavage concurrently with the testosterone injections. Animals were sacrificed at the scheduled termination and the prostates were weighed and subjected to histopathological examination. Testosterone, dihydrotestosterone (DHT), 5α-reductase and cyclooxygenase-2 (COX-2) levels were also measured. BPH-induced animals exhibited an increase in prostate weight with increased testosterone, DHT, 5α-reductase and COX-2 expression levels. However, rape pollen SFE-CO2 treatment resulted in significant reductions in the prostate index and testosterone, DHT, 5α-reductase and COX-2 levels compared with those in BPH-induced animals. Histopathological examination also demonstrated that rape pollen SFE-CO2 treatment suppressed testosterone-induced BPH. These observations indicate that rape pollen SFE-CO2 inhibits the development of BPH in rats and these effects are closely associated with reductions in DHT, 5α-reductase and COX-2 levels. Therefore, the results of the present study clearly indicate that rape pollen SFE-CO2 extract may be a useful agent in BPH treatment. PMID:24944593

Inhibitory effect of rape pollen supercritical CO2 fluid extract against testosterone-induced benign prostatic hyperplasia in rats.

PubMed

Yang, Bi-Cheng; Jin, Li-Li; Yang, Yi-Fang; Li, Kun; Peng, Dan-Ming

2014-07-01

Benign prostatic hyperplasia (BPH) can lead to lower urinary tract symptoms. Rape pollen is an apicultural product that is composed of nutritionally valuable and biologically active substances. The aim of the present study was to investigate the protective effect of rape pollen supercritical CO 2 fluid extract (SFE-CO 2 ) in BPH development using a testosterone-induced BPH rat model. BPH was induced in the experimental groups by daily subcutaneous injections of testosterone for a period of 30 days. Rape pollen SFE-CO 2 was administered daily by oral gavage concurrently with the testosterone injections. Animals were sacrificed at the scheduled termination and the prostates were weighed and subjected to histopathological examination. Testosterone, dihydrotestosterone (DHT), 5α-reductase and cyclooxygenase-2 (COX-2) levels were also measured. BPH-induced animals exhibited an increase in prostate weight with increased testosterone, DHT, 5α-reductase and COX-2 expression levels. However, rape pollen SFE-CO 2 treatment resulted in significant reductions in the prostate index and testosterone, DHT, 5α-reductase and COX-2 levels compared with those in BPH-induced animals. Histopathological examination also demonstrated that rape pollen SFE-CO 2 treatment suppressed testosterone-induced BPH. These observations indicate that rape pollen SFE-CO 2 inhibits the development of BPH in rats and these effects are closely associated with reductions in DHT, 5α-reductase and COX-2 levels. Therefore, the results of the present study clearly indicate that rape pollen SFE-CO 2 extract may be a useful agent in BPH treatment.

The Expression and Significance of Feces Cyclooxygensae-2 mRNA in Colorectal Cancer and Colorectal Adenomas

PubMed Central

Li, Xiaofeng; Kong, Lixia; Liao, Suhuan; Lu, Jing; Ma, Lin; Long, Xiaohua

2017-01-01

Background/Aim: This study aims to explore the expression and significance of feces cyclooxygensae-2 (COX-2) mRNA in colorectal cancer and colorectal adenomas. Materials and Methods: The expression of feces COX-2 mRNA in colorectal cancer (n = 28), colorectal adenomas (n = 54), and normal control group (n = 11) were examined by reverse transcriptase polymerase chain reaction (RT-PCR). The positive rate of fecal occult blood test (FOBT) were detected in colorectal cancer (n = 30), colorectal adenomas (n = 56), and normal control group (n = 11); the sensitivity of the two methods was also compared. Results: The positive rate of feces COX-2 mRNA in colorectal cancer was 82.1% (25/28), which was significantly higher than colorectal adenomas 59.3% (32/54), and normal tissues 18.2% (2/11), the difference being significant between the three groups (χ2= 13.842, P = 0.001). The positive rate of FOBT in colorectal cancer was 73.3% (10/30), which was significantly higher than colorectal adenomas 10.7% (6/56) and normal tissues 9.1% (1/11), the difference being significant between these three groups (χ2= 7.525, P = 0.023). There was no significant association between feces COX-2 expression and various clinical pathological features of colorectal cancer and colorectal adenomas (P > 0.05). The sensitivity of the RT-PCR method is higher than FOBT, however, the specificity of FOBT is slightly higher than RT-PCR. Conclusions: High expression of feces COX-2 mRNA in colorectal adenomas and colorectal cancer is a common event; it is an early event in the development of colorectal adenomas to colorectal cancer. Feces COX-2 mRNA has a high sensitivity for detect colorectal cancer; combination with FOBT will be the best alternative. Feces COX-2 can be potentially used in the early diagnosis and screening of colorectal cancer. PMID:28139497

The expression and significance of feces cyclooxygensae-2 mRNA in colorectal cancer and colorectal adenomas.

PubMed

Li, Xiaofeng; Kong, Lixia; Liao, Suhuan; Lu, Jing; Ma, Lin; Long, Xiaohua

2017-01-01

This study aims to explore the expression and significance of feces cyclooxygensae-2 (COX-2) mRNA in colorectal cancer and colorectal adenomas. The expression of feces COX-2 mRNA in colorectal cancer (n = 28), colorectal adenomas (n = 54), and normal control group (n = 11) were examined by reverse transcriptase polymerase chain reaction (RT-PCR). The positive rate of fecal occult blood test (FOBT) were detected in colorectal cancer (n = 30), colorectal adenomas (n = 56), and normal control group (n = 11); the sensitivity of the two methods was also compared. The positive rate of feces COX-2 mRNA in colorectal cancer was 82.1% (25/28), which was significantly higher than colorectal adenomas 59.3% (32/54), and normal tissues 18.2% (2/11), the difference being significant between the three groups (χ2= 13.842,P= 0.001). The positive rate of FOBT in colorectal cancer was 73.3% (10/30), which was significantly higher than colorectal adenomas 10.7% (6/56) and normal tissues 9.1% (1/11), the difference being significant between these three groups (χ2= 7.525,P= 0.023). There was no significant association between feces COX-2 expression and various clinical pathological features of colorectal cancer and colorectal adenomas (P > 0.05). The sensitivity of the RT-PCR method is higher than FOBT, however, the specificity of FOBT is slightly higher than RT-PCR. High expression of feces COX-2 mRNA in colorectal adenomas and colorectal cancer is a common event; it is an early event in the development of colorectal adenomas to colorectal cancer. Feces COX-2 mRNA has a high sensitivity for detect colorectal cancer; combination with FOBT will be the best alternative. Feces COX-2 can be potentially used in the early diagnosis and screening of colorectal cancer.

Inhibition of cyclooxygenase-2 alleviates liver cirrhosis via improvement of the dysfunctional gut-liver axis in rats.

PubMed

Gao, Jin-Hang; Wen, Shi-Lei; Tong, Huan; Wang, Chun-Hui; Yang, Wen-Juan; Tang, Shi-Hang; Yan, Zhao-Ping; Tai, Yang; Ye, Cheng; Liu, Rui; Huang, Zhi-Yin; Tang, Ying-Mei; Yang, Jin-Hui; Tang, Cheng-Wei

2016-06-01

Inflammatory transport through the gut-liver axis may facilitate liver cirrhosis. Cyclooxygenase-2 (COX-2) has been considered as one of the important molecules that regulates intestinal epithelial barrier function. This study was aimed to test the hypothesis that inhibition of COX-2 by celecoxib might alleviate liver cirrhosis via reduction of intestinal inflammatory transport in thiacetamide (TAA) rat model. COX-2/prostaglandin E2 (PGE2)/EP-2/p-ERK integrated signal pathways regulated the expressions of intestinal zonula occludens-1 (ZO-1) and E-cadherin, which maintain the function of intestinal epithelial barrier. Celecoxib not only decreased the intestinal permeability to a 4-kDa FITC-dextran but also significantly increased expressions of ZO-1 and E-cadherin. When celecoxib greatly decreased intestinal levels of LPS, TNF-α, and IL-6, it significantly enhanced T cell subsets reduced by TAA. As a result, liver fibrosis induced by TAA was significantly alleviated in the celecoxib group. These data indicated that celecoxib improved the integrity of intestinal epithelial barrier, blocked inflammatory transport through the dysfunctional gut-liver axis, and ameliorated the progress of liver cirrhosis. Copyright © 2016 the American Physiological Society.

Luteal activity of pregnant rats with hypo-and hyperthyroidism.

PubMed

Silva, Juneo Freitas; Ocarino, Natália Melo; Serakides, Rogéria

2014-07-12

Luteal activity is dependent on the interaction of various growth factors, cytokines and hormones, including the thyroid hormones, being that hypo- and hyperthyroidism alter the gestational period and are also a cause of miscarriage and stillbirth. Because of that, we evaluated the proliferation, apoptosis and expression of angiogenic factors and COX-2 in the corpus luteum of hypo- and hyperthyroid pregnant rats. Seventy-two adult female rats were equally distributed into three groups: hypothyroid, hyperthyroid and control. Hypo- and hyperthyroidism were induced by the daily administration of propylthiouracil and L-thyroxine, respectively. The administration began five days before becoming pregnant and the animals were sacrificed at days 10, 14, and 19 of gestation. We performed an immunohistochemical analysis to evaluate the expression of CDC-47, VEGF, Flk-1 (VEGF receptor) and COX-2. Apoptosis was evaluated by the TUNEL assay. We assessed the gene expression of VEGF, Flk-1, caspase 3, COX-2 and PGF2α receptor using real time RT-PCR. The data were analyzed by SNK test. Hypothyroidism reduced COX-2 expression on day 10 and 19 (P < 0.05), endothelial/pericyte and luteal cell proliferation on day 10 and 14 (p < 0.05), apoptotic cell numbers on day 19 (p < 0.05) and the expression of Flk-1 and VEGF on day 14 and 19, respectively (p < 0.05). Hyperthyroidism increased the expression of COX-2 on day 19 (P < 0.05) and the proliferative activity of endothelial/pericytes cells on day 14 (p <0.05), as well as the expression of VEGF and Flk-1 on day 19 (P < 0.05). Hypothyroidism reduces the proliferation, apoptosis and expression of angiogenic factors and COX-2in the corpus luteum of pregnant rats, contrary to what is observed in hyperthyroid animals, being this effect dependent of the gestational period.

Luteal activity of pregnant rats with hypo-and hyperthyroidism

PubMed Central

2014-01-01

Background Luteal activity is dependent on the interaction of various growth factors, cytokines and hormones, including the thyroid hormones, being that hypo- and hyperthyroidism alter the gestational period and are also a cause of miscarriage and stillbirth. Because of that, we evaluated the proliferation, apoptosis and expression of angiogenic factors and COX-2 in the corpus luteum of hypo- and hyperthyroid pregnant rats. Methods Seventy-two adult female rats were equally distributed into three groups: hypothyroid, hyperthyroid and control. Hypo- and hyperthyroidism were induced by the daily administration of propylthiouracil and L-thyroxine, respectively. The administration began five days before becoming pregnant and the animals were sacrificed at days 10, 14, and 19 of gestation. We performed an immunohistochemical analysis to evaluate the expression of CDC-47, VEGF, Flk-1 (VEGF receptor) and COX-2. Apoptosis was evaluated by the TUNEL assay. We assessed the gene expression of VEGF, Flk-1, caspase 3, COX-2 and PGF2α receptor using real time RT-PCR. The data were analyzed by SNK test. Results Hypothyroidism reduced COX-2 expression on day 10 and 19 (P < 0.05), endothelial/pericyte and luteal cell proliferation on day 10 and 14 (p < 0.05), apoptotic cell numbers on day 19 (p < 0.05) and the expression of Flk-1 and VEGF on day 14 and 19, respectively (p < 0.05). Hyperthyroidism increased the expression of COX-2 on day 19 (P < 0.05) and the proliferative activity of endothelial/pericytes cells on day 14 (p <0.05), as well as the expression of VEGF and Flk-1 on day 19 (P < 0.05). Conclusions Hypothyroidism reduces the proliferation, apoptosis and expression of angiogenic factors and COX-2in the corpus luteum of pregnant rats, contrary to what is observed in hyperthyroid animals, being this effect dependent of the gestational period. PMID:25298361

Downregulation of NF-κB and PCNA in the regulatory pathways of apoptosis by cyclooxygenase-2 inhibitors in experimental lung cancer.

PubMed

Setia, Shruti; Sanyal, Sankar Nath

2012-10-01

Non-steroidal anti-inflammatory drugs (NSAIDs) are emerging as novel chemopreventive agents against a variety of cancers owing to their capability in blocking the tumor development by cellular proliferation, angiogenesis and by promoting apoptosis. The present study further explored the comparative role of a traditional NSAID, indomethacin and a newly developed coxib, etoricoxib against 9,10-dimethylbenz(a)anthracene (DMBA)-induced lung carcinogenesis in rats. Morphological and histological analysis revealed the occurrence of tumors and lesions along with constricted alveolar spaces in the DMBA treated animals which were largely corrected both by indomethacin and etoricoxib. COX-1 was found to be uniformly expressed in all the groups while COX-2 levels were raised prominently in the DMBA treated animals. Proliferation, as studied by PCNA expression was found to be markedly increased in the DMBA group as compared to the others. Increased NF-κB expression in the DMBA group was found to correct with the co-administration of NSAIDs. Also, fluorescent co-staining of the isolated lung cells revealed a significantly decreased apoptosis and altered mitochondrial membrane potential. In conclusion, these parameters indicate to the chemopreventive action of the two NSAIDs studied in lung cancer and as their mechanism of action suggests, can be achievable both by COX-dependent and COX-independent pathways.

Anti-inflammatory effect of the water fraction from hawthorn fruit on LPS-stimulated RAW 264.7 cells

PubMed Central

Li, Chunmei

2011-01-01

The hawthorn fruit (Crataegus pinnatifida Bunge var. typica Schneider) is used as a traditional medicine in Korea. The objective of this study was to understand the mechanisms of the anti-inflammatory effects of the water fractionated portion of hawthorn fruit on a lipopolysaccharide (LPS)-stimulated RAW 264.7 cellular model. The level of nitric oxide (NO) production in the water fraction and LPS-treated RAW 264.7 cells were determined with an ELISA. The cytotoxicity of the water fraction and LPS was measured with an MTT assay. Expression of nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor (TNF)-α, interleukin 6 (IL-6), and interleukin 1β (IL-1β) mRNA were analyzed with a reverse transcription polymerase chain reaction (RT-PCR). The water fraction of hawthorn fruit was determined to be safe and significantly inhibited NO production in LPS-stimulated RAW 264.7 cells and suppressed COX-2, TNF-α, IL-1β, and IL-6 expression. The observed anti-inflammatory effects of the water fraction of hawthorn fruit might be attributed to the down-regulation of COX-2, TNF-α, IL-1β, and IL-6 expression in LPS-stimulated RAW 264.7 cells. PMID:21556222

Rapid development of colitis in NSAID-treated IL-10-deficient mice.

PubMed

Berg, Daniel J; Zhang, Juan; Weinstock, Joel V; Ismail, Hanan F; Earle, Keith A; Alila, Hector; Pamukcu, Rifat; Moore, Steven; Lynch, Richard G

2002-11-01

Interleukin (IL)-10 is an anti-inflammatory and immune regulatory cytokine. IL-10-deficient mice (IL-10(-/-)) develop chronic inflammatory bowel disease (IBD), indicating that endogenous IL-10 is a central regulator of the mucosal immune response. Prostaglandins are lipid mediators that may be important mediators of intestinal inflammation. In this study we assessed the role of prostaglandins in the regulation of mucosal inflammation in the IL-10(-/-) mouse model of IBD. Prostaglandin (PG) synthesis was inhibited with nonselective or cyclooxygenase (COX)-isoform selective inhibitors. Severity of inflammation was assessed histologically. Cytokine production was assessed by ribonuclease protection analysis and enzyme-linked immunosorbent assay. PGE(2) levels were assessed by enzyme immunoassay. COX-1 and COX-2 expression was assessed by Western blot analysis. Nonsteroidal anti-inflammatory drug (NSAID) treatment of wild-type mice had minimal effect on the colon. In contrast, NSAID treatment of 4-week-old IL-10(-/-) mice resulted in rapid development of colitis characterized by infiltration of the lamina propria with macrophages and interferon gamma-producing CD4(+) T cells. Colitis persisted after withdrawal of the NSAID. NSAID treatment decreased colonic PGE(2) levels by 75%. Treatment of IL-10(-/-) mice with sulindac sulfone (which does not inhibit PG production) did not induce colitis whereas the NSAID sulindac induced severe colitis. COX-1- or COX-2-selective inhibitors used alone did not induce IBD in IL-10(-/-) mice. However, the combination of COX-1- and COX-2-selective inhibitors did induce colitis. NSAID treatment of IL-10(-/-) mice results in the rapid development of severe, chronic IBD. Endogenous PGs are important inhibitors of the development of intestinal inflammation in IL-10(-/-) mice.

The influence of acute resistance exercise on cyclooxygenase-1 and -2 activity and protein levels in human skeletal muscle.

PubMed

Carroll, Chad C; O'Connor, Devin T; Steinmeyer, Robert; Del Mundo, Jonathon D; McMullan, David R; Whitt, Jamie A; Ramos, Jahir E; Gonzales, Rayna J

2013-07-01

This study evaluated the activity and content of cyclooxygenase (COX)-1 and -2 in response to acute resistance exercise (RE) in human skeletal muscle. Previous work suggests that COX-1, but not COX-2, is the primary COX isoform elevated with resistance exercise in human skeletal muscle. COX activity, however, has not been assessed after resistance exercise in humans. It was hypothesized that RE would increase COX-1 but not COX-2 activity. Muscle biopsies were taken from the vastus lateralis of nine young men (25 ± 1 yr) at baseline (preexercise), 4, and 24 h after a single bout of knee extensor RE (three sets of 10 repetitions at 70% of maximum). Tissue lysate was assayed for COX-1 and COX-2 activity. COX-1 and COX-2 protein levels were measured via Western blot analysis. COX-1 activity increased at 4 h (P < 0.05) compared with preexercise, but returned to baseline at 24 h (PRE: 60 ± 10, 4 h: 106 ± 22, 24 h: 72 ± 8 nmol PGH2·g total protein(-1)·min(-1)). COX-2 activity was elevated at 4 and 24 h after RE (P < 0.05, PRE: 51 ± 7, 4 h: 100 ± 19, 24 h: 98 ± 14 nmol PGH2·g total protein(-1)·min(-1)). The protein level of COX-1 was not altered (P > 0.05) with acute RE. In contrast, COX-2 protein levels were nearly 3-fold greater (P > 0.05) at 4 h and 5-fold greater (P = 0.06) at 24 h, compared with preexercise. In conclusion, COX-1 activity increases transiently with exercise independent of COX-1 protein levels. In contrast, both COX-2 activity and protein levels were elevated with exercise, and this elevation persisted to at least 24 h after RE.

Effects of flavocoxid, a dual inhibitor of COX and 5-lipoxygenase enzymes, on benign prostatic hyperplasia

PubMed Central

Altavilla, D; Minutoli, L; Polito, F; Irrera, N; Arena, S; Magno, C; Rinaldi, M; Burnett, BP; Squadrito, F; Bitto, A

2012-01-01

BACKGROUND AND PURPOSE Inflammation plays a key role in the development of benign prostatic hyperplasia (BPH). Eicosanoids derived from the COX and 5-lipoxygenase (5-LOX) pathways are elevated in the enlarging prostate. Flavocoxid is a novel flavonoid–based ‘dual inhibitor’ of the COX and 5-LOX enzymes. This study evaluated the effects of flavocoxid in experimental BPH. EXPERIMENTAL APPROACH Rats were treated daily with testosterone propionate (3 mg·kg−1 s.c.) or its vehicle for 14 days to induce BPH. Animals receiving testosterone were randomized to receive vehicle (1 mL·kg−1, i.p.) or flavocoxid (20 mg·kg−1, i.p.) for 14 days. Histological changes, eicosanoid content and mRNA and protein levels for apoptosis-related proteins and growth factors were assayed in prostate tissue. The effects of flavocoxid were also tested on human prostate carcinoma PC3 cells. KEY RESULTS Flavocoxid reduced prostate weight and hyperplasia, blunted inducible expression of COX-2 and 5-LOX as well as the increased production of PGE2 and leukotriene B4 (LTB4), enhanced pro-apoptotic Bax and caspase-9 and decreased the anti-apoptotic Bcl-2 mRNA. Flavocoxid also reduced EGF and VEGF expression. In PC3 cells, flavocoxid stimulated apoptosis and inhibited growth factor expression. Flavocoxid-mediated induction of apoptosis was inhibited by the pan-caspase inhibitor, Z-VAD-FMK, in PC3 cells, suggesting an essential role of caspases in flavocoxid-mediated apoptosis during prostatic growth. CONCLUSION AND IMPLICATIONS Our results show that a ‘dual inhibitor’ of the COX and 5-LOX enzymes, such as flavocoxid, might represent a rational approach to reduce BPH through modulation of eicosanoid production and a caspase-induced apoptotic mechanism. PMID:22471974

Effects of flavocoxid, a dual inhibitor of COX and 5-lipoxygenase enzymes, on benign prostatic hyperplasia.

PubMed

Altavilla, D; Minutoli, L; Polito, F; Irrera, N; Arena, S; Magno, C; Rinaldi, M; Burnett, B P; Squadrito, F; Bitto, A

2012-09-01

Inflammation plays a key role in the development of benign prostatic hyperplasia (BPH). Eicosanoids derived from the COX and 5-lipoxygenase (5-LOX) pathways are elevated in the enlarging prostate. Flavocoxid is a novel flavonoid-based 'dual inhibitor' of the COX and 5-LOX enzymes. This study evaluated the effects of flavocoxid in experimental BPH. Rats were treated daily with testosterone propionate (3 mg·kg(-1)  s.c.) or its vehicle for 14 days to induce BPH. Animals receiving testosterone were randomized to receive vehicle (1 mL·kg(-1) , i.p.) or flavocoxid (20 mg·kg(-1) , i.p.) for 14 days. Histological changes, eicosanoid content and mRNA and protein levels for apoptosis-related proteins and growth factors were assayed in prostate tissue. The effects of flavocoxid were also tested on human prostate carcinoma PC3 cells. Flavocoxid reduced prostate weight and hyperplasia, blunted inducible expression of COX-2 and 5-LOX as well as the increased production of PGE(2) and leukotriene B(4) (LTB(4) ), enhanced pro-apoptotic Bax and caspase-9 and decreased the anti-apoptotic Bcl-2 mRNA. Flavocoxid also reduced EGF and VEGF expression. In PC3 cells, flavocoxid stimulated apoptosis and inhibited growth factor expression. Flavocoxid-mediated induction of apoptosis was inhibited by the pan-caspase inhibitor, Z-VAD-FMK, in PC3 cells, suggesting an essential role of caspases in flavocoxid-mediated apoptosis during prostatic growth. Our results show that a 'dual inhibitor' of the COX and 5-LOX enzymes, such as flavocoxid, might represent a rational approach to reduce BPH through modulation of eicosanoid production and a caspase-induced apoptotic mechanism. © 2012 The Authors. British Journal of Pharmacology © 2012 The British Pharmacological Society.

Gq protein mediates UVB-induced cyclooxygenase-2 expression by stimulating HB-EGF secretion from HaCaT human keratinocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seo, MiRan; Juhnn, Yong-Sung, E-mail: juhnn@snu.ac.kr

Ultraviolet (UV) radiation induces cyclooxygenase-2 expression to produce cellular responses including aging and carcinogenesis in skin. We hypothesised that heterotrimeric G proteins mediate UV-induced COX-2 expression by stimulating secretion of soluble HB-EGF (sHB-EGF). In this study, we aimed to elucidate the role and underlying mechanism of the {alpha} subunit of Gq protein (G{alpha}q) in UVB-induced HB-EGF secretion and COX-2 induction. We found that expression of constitutively active G{alpha}q (G{alpha}qQL) augmented UVB-induced HB-EGF secretion, which was abolished by knockdown of G{alpha}q with shRNA in HaCaT human keratinocytes. G{alpha}q was found to mediate the UVB-induced HB-EGF secretion by sequential activation of phospholipasemore » C (PLC), protein kinase C{delta} (PKC{delta}), and matrix metaloprotease-2 (MMP-2). Moreover, G{alpha}qQL mediated UVB-induced COX-2 expression in an HB-EGF-, EGFR-, and p38-dependent manner. From these results, we concluded that G{alpha}q mediates UV-induced COX-2 expression through activation of EGFR by HB-EGF, of which ectodomain shedding was stimulated through sequential activation of PLC, PKC{delta} and MMP-2 in HaCaT cells.« less

Nicotine impairs cyclooxygenase-2-dependent kinin-receptor-mediated murine airway relaxations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Yuan, E-mail: yuan.xu@ki.se; Cardell, Lars-Olaf

Introduction: Cigarette smoke induces local inflammation and airway hyperreactivity. In asthmatics, it worsens the symptoms and increases the risk for exacerbation. The present study investigates the effects of nicotine on airway relaxations in isolated murine tracheal segments. Methods: Segments were cultured for 24 h in the presence of vehicle, nicotine (10 μM) and/or dexamethasone (1 μM). Airway relaxations were assessed in myographs after pre-contraction with carbachol (1 μM). Kinin receptors, cyclooxygenase (COX) and inflammatory mediator expressions were assessed by real-time PCR and confocal-microscopy-based immunohistochemistry. Results: The organ culture procedure markedly increased bradykinin- (selective B{sub 2} receptor agonist) and des-Arg{sup 9}-bradykinin-more » (selective B{sub 1} receptor agonist) induced relaxations, and slightly increased relaxation induced by isoprenaline, but not that induced by PGE{sub 2}. The kinin receptor mediated relaxations were epithelium-, COX-2- and EP2-receptor-dependent and accompanied by drastically enhanced mRNA levels of kinin receptors, as well as inflammatory mediators MCP-1 and iNOS. Increase in COX-2 and mPGES-1 was verified both at mRNA and protein levels. Nicotine selectively suppressed the organ-culture-enhanced relaxations induced by des-Arg{sup 9}-bradykinin and bradykinin, at the same time reducing mPGES-1 mRNA and protein expressions. α7-nicotinic acetylcholine receptor inhibitors α-bungarotoxin and MG624 both blocked the nicotine effects on kinin B{sub 2} receptors, but not those on B{sub 1}. Dexamethasone completely abolished kinin-induced relaxations. Conclusion: It is tempting to conclude that a local inflammatory process per se could have a bronchoprotective component by increasing COX-2 mediated airway relaxations and that nicotine could impede this safety mechanism. Dexamethasone further reduced airway inflammation together with relaxations. This might contribute to the steroid resistance seen in some patients with asthma. - Highlights: • Nicotine from smoking impaired epithelial COX-2-mediated airway relaxation. • Nicotine's effects were at least partially mediated by α7-nicotinic receptors. • Kinin-receptor-mediated airway relaxations are mediated by EP2 receptors in mice. • Nicotine reduced mPGES-1 mRNA and protein expressions in airway smooth muscle. • Dexamethasone could not restore nicotine-impaired airway relaxations.« less

The protective effect of total phenolics from Oenanthe Javanica on acute liver failure induced by D-galactosamine.

PubMed

Ai, Guo; Huang, Zheng-Ming; Liu, Qing-Chuan; Han, Yan-Quan; Chen, Xi

2016-06-20

Water dropwort [Oenanthe javanica (O. javanica)] is an aquatic perennial herb cultivated in East Asian countries. It has been popularly used in traditional Chinese medicine which is beneficial for the treatment of many diseases, including jaundice and various types of chronic and acute hepatitis. In the present study, we investigated the hepatoprotective effect of total phenolics from O. javanica (TPOJ) against D-galactosamine (D-GalN) induced liver injury in mice. The hepatoprotective activity of TPOJ (125, 250 and 500mg/kg) was investigated on D-GalN (800mg/kg)-induced liver damages in mice. Blood and liver were collected for biochemical and microscopic analysis. RT-PCR was used to determine the changes in hepatic nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression. Protein levels of iNOS, COX-2, superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) were determined by western blotting. In the animal studies, TPOJ could improve the survival of acute liver failure model significantly and prevente the D-GalN-induced elevation of the serum enzymatic markers and nonenzymatic markers levels significantly. Meanwhile, TPOJ-treatment decreased the malondialdehyde (MDA) level and elevated the content of glutathione (GSH) in the liver as compared to those in the D-GalN group. Hepatic activities and protein expressions of antioxidative enzymes, including SOD, GPx, and CAT were enhanced dose dependently with TPOJ. At the same time, application of TPOJ effectively suppressed the D-GalN-induced proinflammatory mRNA and protein expression of iNOS and COX-2. Subsequently, the serum levels of proinflammatory mediators, nitric oxide (NO) and prostaglandin E2 (PGE2) were reduced. Additionally, histological analyses also showed that TPOJ reduced the extent of liver lesions induced by D-GalN. Our investigation demonstrated the hepatoprotective activity of TPOJ and revealed that TPOJ attributed its significance in the traditional use for treating liver diseases. Copyright © 2016. Published by Elsevier Ireland Ltd.

Novel insights into the regulation of cyclooxygenase-2 expression by platelet-cancer cell cross-talk

PubMed Central

Dovizio, Melania; Alberti, Sara; Sacco, Angela; Guillem-Llobat, Paloma; Schiavone, Simone; Maier, Thorsten J.; Steinhilber, Dieter; Patrignani, Paola

2015-01-01

Platelets are activated by the interaction with cancer cells and release enhanced levels of lipid mediators [such as thromboxane (TX)A2 and prostaglandin (PG)E2, generated from arachidonic acid (AA) by the activity of cyclooxygenase (COX)-1], granule content, including ADP and growth factors, chemokines, proteases and Wnt proteins. Moreover, activated platelets shed different vesicles, such as microparticles (MPs) and exosomes (rich in genetic material such as mRNAs and miRNAs). These platelet-derived products induce several phenotypic changes in cancer cells which confer high metastatic capacity. A central event involves an aberrant expression of COX-2 which influences cell-cycle progression and contribute to the acquisition of a cell migratory phenotype through the induction of epithelial mesenchymal transition genes and down-regulation of E-cadherin expression. The identification of novel molecular determinants involved in the cross-talk between platelets and cancer cells has led to identify novel targets for anti-cancer drug development. PMID:26551717

Signaling of Prostaglandin E Receptors, EP3 and EP4 Facilitates Wound Healing and Lymphangiogenesis with Enhanced Recruitment of M2 Macrophages in Mice.

PubMed

Hosono, Kanako; Isonaka, Risa; Kawakami, Tadashi; Narumiya, Shuh; Majima, Masataka

2016-01-01

Lymphangiogenesis plays an important role in homeostasis, metabolism, and immunity, and also occurs during wound-healing. Here, we examined the roles of prostaglandin E2 (PGE2) receptor (EP) signaling in enhancement of lymphangiogenesis in wound healing processes. The hole-punch was made in the ears of male C57BL/6 mice using a metal ear punch. Healing process and lymphangiogenesis together with macrophage recruitment were analyzed in EP knockout mice. Lymphangiogenesis was up-regulated in the granulation tissues at the margins of punched-hole wounds in mouse ears, and this increase was accompanied by increased expression levels of COX-2 and microsomal prostaglandin E synthase-1. Administration of celecoxib, a COX-2 inhibitor, suppressed lymphangiogenesis in the granulation tissues and reduced the induction of the pro-lymphangiogenic factors, vascular endothelial growth factor (VEGF) -C and VEGF-D. Topical applications of selective EP receptor agonists enhanced the expressions of lymphatic vessel endothelial hyaluronan receptor-1 and VEGF receptor-3. The wound-healing processes and recruitment of CD11b-positive macrophages, which produced VEGF-C and VEGF-D, were suppressed under COX-2 inhibition. Mice lacking either EP3 or EP4 exhibited reduced wound-healing, lymphangiogenesis and recruitment of M2 macrophages, compared with wild type mice. Proliferation of cultured human lymphatic endothelial cells was not detected under PGE2 stimulation. Lymphangiogenesis and recruitment of M2 macrophages that produced VEGF-C/D were suppressed in mice treated with a COX-2 inhibitor or lacking either EP3 or EP4 during wound healing. COX-2 and EP3/EP4 signaling may be novel targets to control lymphangiogenesis in vivo.

Mercury induces proliferation and reduces cell size in vascular smooth muscle cells through MAPK, oxidative stress and cyclooxygenase-2 pathways

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aguado, Andrea; Galán, María; Zhenyukh, Olha

2013-04-15

Mercury exposure is known to increase cardiovascular risk but the underlying cellular mechanisms remain undetermined. We analyzed whether chronic exposure to HgCl{sub 2} affects vascular structure and the functional properties of vascular smooth muscle cells (VSMC) through oxidative stress/cyclooxygenase-2 dependent pathways. Mesenteric resistance arteries and aortas from Wistar rats treated with HgCl{sub 2} (first dose 4.6 mg kg{sup −1}, subsequent doses 0.07 mg kg{sup −1} day{sup −1}, 30 days) and cultured aortic VSMC stimulated with HgCl{sub 2} (0.05–5 μg/ml) were used. Treatment of rats with HgCl{sub 2} decreased wall thickness of the resistance and conductance vasculature, increased the number ofmore » SMC within the media and decreased SMC nucleus size. In VSMCs, exposure to HgCl{sub 2}: 1) induced a proliferative response and a reduction in cell size; 2) increased superoxide anion production, NADPH oxidase activity, gene and/or protein levels of the NADPH oxidase subunit NOX-1, the EC- and Mn-superoxide dismutases and cyclooxygenase-2 (COX-2); 3) induced activation of ERK1/2 and p38 MAPK. Both antioxidants and COX-2 inhibitors normalized the proliferative response and the altered cell size induced by HgCl{sub 2}. Blockade of ERK1/2 and p38 signaling pathways abolished the HgCl{sub 2}-induced Nox1 and COX-2 expression and normalized the alterations induced by mercury in cell proliferation and size. In conclusion, long exposure of VSMC to low doses of mercury activates MAPK signaling pathways that result in activation of inflammatory proteins such as NADPH oxidase and COX-2 that in turn induce proliferation of VSMC and changes in cell size. These findings offer further evidence that mercury might be considered an environmental risk factor for cardiovascular disease. - Highlights: ► Chronic HgCl{sub 2} exposure induces vascular remodeling. ► HgCl{sub 2} induces proliferation and decreased cell size in vascular smooth muscle cells. ► HgCl{sub 2} induces MAPK activation, oxidative stress and COX-2 expression. ► Inhibition of MAPK reduces HgCl{sub 2}-induced oxidative stress and COX-2 expression. ► Inhibition of MAPK, oxidative stress and COX-2 restores the altered cell proliferation and size.« less

Canine mesenchymal stem cells treated with TNF-α and IFN-γ enhance anti-inflammatory effects through the COX-2/PGE2 pathway.

PubMed

Yang, Hye-Mi; Song, Woo-Jin; Li, Qiang; Kim, Su-Yeon; Kim, Hyeon-Jin; Ryu, Min-Ok; Ahn, Jin-Ok; Youn, Hwa-Young

2018-05-14

Mesenchymal stem cells (MSCs) have been used in studies on treatment of various diseases, and their application to immune-mediated diseases has garnered interest. Various methods for enhancing the immunomodulation effect of human MSCs have been used; however, similar approaches for canine MSCs are relatively unexplored. Accordingly, we evaluated immunomodulatory effects and mechanisms in canine MSCs treated with TNF-α and IFN-γ. Lipopolysaccharide (LPS)-stimulated RAW 264.7 cells were incubated with the conditioned media (CM) from canine MSCs for 48 h. Expression of RNA was assessed by quantitative reverse transcription PCR (qRT-PCR), and protein levels were assessed by western blot. Expression of inducible nitric oxide synthase (iNOS), IL-6 and IL-1β was significantly (one-way ANOVA) decreased in LPS-stimulated RAW 264.7 cells incubated with CM from canine MSCs compared to that in LPS-stimulated RAW 264.7 cells alone. Furthermore, anti-inflammatory effects of TNF-α- and IFN-γ-primed canine MSCs were significantly increased compared with those of naïve canine MSCs. Expression of cyclooxygenase 2 (COX-2) and prostaglandin E 2 (PGE 2 ) were likewise significantly increased in primed canine MSCs. The level of iNOS protein in LPS-stimulated RAW 264.7 cells incubated with CM from the primed canine MSCs was decreased, but it increased when the cells were treated with NS-398(PGE 2 inhibitor). In conclusion, compared with naïve canine MSCs, cells primed with TNF-α and IFN-γ cause a greater reduction in release of anti-inflammatory cytokines from LPS-stimulated RAW 264.7 cells; the mechanism is upregulation of the COX-2/PGE 2 pathway. Copyright © 2018. Published by Elsevier Ltd.

Comparative inhibitory effects of magnolol, honokiol, eugenol and bis-eugenol on cyclooxygenase-2 expression and nuclear factor-kappa B activation in RAW264.7 macrophage-like cells stimulated with fimbriae of Porphyromonas gingivalis.

PubMed

Murakami, Yukio; Kawata, Akifumi; Seki, Yuya; Koh, Teho; Yuhara, Kenji; Maruyama, Takehisa; Machino, Mamoru; Ito, Shigeru; Kadoma, Yoshinori; Fujisawa, Seiichiro

2012-01-01

The anti-inflammatory activity of magnolol and related compounds is currently a focus of interest. In the present study, the inhibitory effects of these compounds on cyclooxygenase (COX-2) expression and nuclear factor-kappa B (NF-κB) activation were investigated in RAW264.7 macrophage-like cells stimulated with the fimbriae of Porphyromonas gingivalis, an oral anaerobe. The cytotoxicity of magnolol, honokiol, eugenol and bis-eugenol against RAW264.7 cells was determined using a cell counting kit (CCK-8). The regulatory effect of these compounds on the expression of COX-2 mRNA, stimulated by exposure to the fimbriae was investigated by real-time polymerase chain reaction (PCR). NF-κB activation was evaluated by enzyme-linked immunosorbent assay (ELISA)-like microwell colorimetric transcription factor activity assay (Trans-AM) and western blot analysis. The radical-scavenging activity was determined using the induction period method in the methyl methacrylate-azobisisobutyronitrile (AIBN) polymerization system under nearly anaerobic conditions. The phenolic bond dissociation enthalpy (BDE) and orbital energy were calculated at the density functional theory (DFT) B3LYP/6-31G* level. The cytotoxicity against RAW264.7 cells declined in the order bis-eugenol>eugenol> honokiol>magnolol, whereas the radical-scavenging activity declined in the order honokiol, bis-eugenol>magnolol> eugenol. Magnolol and honokiol significantly inhibited the fimbria-induced expression of COX-2 at non-cytotoxic concentrations. Both the fimbria-stimulated binding of NF-κB to its consensus sequence and phosphorylation-dependent proteolysis of inhibitor κB-α were markedly inhibited by magnilol and honokiol, whereas eugenol and bis-eugenol did not inhibit COX-2 expression and NF-κB activation. Magnolol and honokiol possessed a high electronegativity (χ) value. Magnolol and honokiol exhibit antioxidative activity, low cytotoxicity, and anti-inflammatory activity. These compounds may be capable of preventing chronic inflammatory diseases induced by oral bacteria.

Microsomal PGE2 synthase-1 regulates melanoma cell survival and associates with melanoma disease progression

PubMed Central

Kim, Sun-Hee; Hashimoto, Yuuri; Cho, Sung-Nam; Roszik, Jason; Milton, Denái R.; Dal, Fulya; Kim, Sangwon F.; Menter, David G.; Yang, Peiying; Ekmekcioglu, Suhendan; Grimm, Elizabeth A.

2016-01-01

Summary COX-2 and its product PGE2 enhance carcinogenesis and tumor progression, which has been previously reported in melanoma. As most COX inhibitors cause much toxicity, the downstream microsomal PGE2 synthase-1 (mPGES1) is a consideration for targeting. Human melanoma TMAs were employed for testing mPGES1 protein staining intensity and percentage levels and both increased with clinical stage; employing a different Stage III TMA, mPGES1 intensity (not percentage) associated with reduced patient survival. Our results further show that iNOS was also highly expressed in melanoma tissues with high mPGES1 levels, and iNOS-mediated NO promoted mPGES1 expression and PGE2 production. An mPGES1specific inhibitor (CAY10526) as well as siRNA attenuated cell survival and increased apoptosis. CAY10526 significantly suppressed tumor growth and increased apoptosis in melanoma xenografts. Our findings support the value of a prognostic and predictive role for mPGES1, and suggest targeting this molecule in the PGE2 pathway as another avenue toward improving melanoma therapy. PMID:26801201

Quercetin protects rat dorsal root ganglion neurons against high glucose-induced injury in vitro through Nrf-2/HO-1 activation and NF-κB inhibition.

PubMed

Shi, Yue; Liang, Xiao-chun; Zhang, Hong; Wu, Qun-li; Qu, Ling; Sun, Qing

2013-09-01

To examine the effects of quercetin, a natural antioxidant, on high glucose (HG)-induced apoptosis of cultured dorsal root ganglion (DRG) neurons of rats. DRG neurons exposed to HG (45 mmol/L) for 24 h were employed as an in vitro model of diabetic neuropathy. Cell viability, reactive oxygen species (ROS) level and apoptosis were determined. The expression of NF-кB, IкBα, phosphorylated IкBα and Nrf2 was examined using RT PCR and Western blot assay. The expression of hemeoxygenase-1 (HO-1), IL-6, TNF-α, iNOS, COX-2, and caspase-3 were also examined. HG treatment markedly increased DRG neuron apoptosis via increasing intracellular ROS level and activating the NF-κB signaling pathway. Co-treatment with quercetin (2.5, 5, and 10 mmol/L) dose-dependently decreased HG-induced caspase-3 activation and apoptosis. Quercetin could directly scavenge ROS and significantly increased the expression of Nrf-2 and HO-1 in DRG neurons. Quercetin also dose-dependently inhibited the NF-κB signaling pathway and suppressed the expression of iNOS, COX-2, and proinflammatory cytokines IL-6 and TNF-α. Quercetin protects rat DRG neurons against HG-induced injury in vitro through Nrf-2/HO-1 activation and NF-κB inhibition, thus may be beneficial for the treatment of diabetic neuropathy.

Inhibitory Effects of Culinary Herbs and Spices on the Growth of HCA-7 Colorectal Cancer Cells and Their COX-2 Expression.

PubMed

Jaksevicius, Andrius; Carew, Mark; Mistry, Calli; Modjtahedi, Helmout; Opara, Elizabeth I

2017-09-21

It is unclear if the anti-inflammatory properties of culinary herbs and spices (CHS) are linked to their ability to inhibit Colorectal cancer cell (CRC) growth. Furthermore, their therapeutic potential with regards to CRC is unknown. The aim of this study was to establish if the inhibition of HCA-7 CRC cell growth by a selection of culinary herbs and spices (CHS) is linked to the inhibition of the cells' cyclooxygenase-2 (COX-2 )expression, and to investigate their therapeutic potential. CHS inhibited the growth of Human colon adenocarcinoma-7 (HCA-7) cells; the order of potency was turmeric, bay leaf, ginger, sage, and rosemary; their combinations had a synergistic or additive effect on cell growth inhibition. CHS also inhibited COX-2 expression and activity; this action was comparable to that of the specific COX-2 inhibitor Celecoxib. Coincident with COX-2 inhibition was the accumulation of cells in the sub G1 phase of the HCA-7's cell cycle and, using bay leaf and turmeric, the cleavage of caspase 3 and poly (ADP-ribose) polymerase (PARP). This latter effect showed that the effect of these CHS on growth arrest was irreversible, and was comparable to that of the caspase activator Etoposide. This study provides evidence of a link between the inhibition of HCA-7 growth, and its COX-2 expression, by CHS, and their therapeutic potential.

Inhibitory Effects of Culinary Herbs and Spices on the Growth of HCA-7 Colorectal Cancer Cells and Their COX-2 Expression

PubMed Central

Jaksevicius, Andrius; Carew, Mark; Mistry, Calli

2017-01-01

It is unclear if the anti-inflammatory properties of culinary herbs and spices (CHS) are linked to their ability to inhibit Colorectal cancer cell (CRC) growth. Furthermore, their therapeutic potential with regards to CRC is unknown. The aim of this study was to establish if the inhibition of HCA-7 CRC cell growth by a selection of culinary herbs and spices (CHS) is linked to the inhibition of the cells’ cyclooxygenase-2 (COX-2 )expression, and to investigate their therapeutic potential. CHS inhibited the growth of Human colon adenocarcinoma-7 (HCA-7) cells; the order of potency was turmeric, bay leaf, ginger, sage, and rosemary; their combinations had a synergistic or additive effect on cell growth inhibition. CHS also inhibited COX-2 expression and activity; this action was comparable to that of the specific COX-2 inhibitor Celecoxib. Coincident with COX-2 inhibition was the accumulation of cells in the sub G1 phase of the HCA-7’s cell cycle and, using bay leaf and turmeric, the cleavage of caspase 3 and poly (ADP-ribose) polymerase (PARP). This latter effect showed that the effect of these CHS on growth arrest was irreversible, and was comparable to that of the caspase activator Etoposide. This study provides evidence of a link between the inhibition of HCA-7 growth, and its COX-2 expression, by CHS, and their therapeutic potential. PMID:28934138

COX-2 expression and function in the hyperalgesic response to paw inflammation in mice

PubMed Central

Jain, Naveen K.; Ishikawa, Tomo-o; Spigelman, Igor; Herschman, Harvey R.

2009-01-01

Peripheral inflammation and edema are often accompanied by primary and secondary hyperalgesia which are mediated by both peripheral and central mechanisms. The role of cyclooxygenase-2 (COX-2)-mediated prostanoid production in hyperalgesia is a topic of substantial current interest. We have established a murine foot-pad inflammation model in which both pharmacologic and genetic tools can be used to characterize the role of COX-2 in hyperalgesia. Zymosan, an extract from yeast, injected into the plantar surface of the hind paw induces an edema response and an increase in COX-2 expression in the hindpaw, spinal cord and brain. Zymosan-induced primary hyperalgesia, measured as a decrease in hindpaw withdrawal latency in response to a thermal stimulus, is long-lasting and is not inhibited by pre-treatment with the systemic COX-2 selective inhibitor, parecoxib (20 mg/kg). In contrast, the central component of hyperalgesia, measured as a reduction in tail flick latency in response to heat, is reduced by parecoxib. Zymosan-induced primary hyperalgesia in Cox-2−/− mice is similar to that of their Cox-2+/+ littermate controls. However, the central component of hyperalgesia is substantially reduced in Cox-2−/− versus Cox-2+/+ mice, and returns to baseline values much more rapidly. Thus pharmacological data suggest, and genetic experiments confirm, (i) that primary hyperalgesia in response to zymosan inflammation in the mouse paw is not mediated by COX-2 function and (ii) that COX-2 function plays a major role in the central component of hyperalgesia in this model of inflammation. PMID:18829279

Cyclic Tensile Strain Upregulates Pro-Inflammatory Cytokine Expression Via FAK-MAPK Signaling in Chondrocytes.

PubMed

Yanoshita, Makoto; Hirose, Naoto; Okamoto, Yuki; Sumi, Chikako; Takano, Mami; Nishiyama, Sayuri; Asakawa-Tanne, Yuki; Horie, Kayo; Onishi, Azusa; Yamauchi, Yuka; Mitsuyoshi, Tomomi; Kunimatsu, Ryo; Tanimoto, Kotaro

2018-05-08

Excessive mechanical stimulation is considered an important factor in the destruction of chondrocytes. Focal adhesion kinase (FAK) is non-receptor tyrosine kinase related to a number of different signaling proteins. Little is known about the function of FAK in chondrocytes under mechanical stimulation. In the present study, we investigated the function of FAK in mechanical signal transduction and the mechanism through which cyclic tensile strain (CTS) induces expression of inflammation-related factors. Mouse ATDC5 chondrogenic cells were subjected to CTS of 0.5 Hz to 10% cell elongation with an FAK inhibitor. The expression of genes encoding COX-2, IL-1β, and TNF-α was examined using real-time RT-PCR after CTS application with FAK inhibitor. Phosphorylation of p-38, ERK, and JNK was analyzed by Western blotting. Differences in COX-2 expression following pretreatment with FAK, p-38, ERK, and JNK inhibitors were compared by Western blotting. We found that CTS increased the expression of genes encoding COX-2, IL-1β, and TNF-α and activated the phosphorylation of FAK, p-38, ERK, and JNK. Pretreatment with an FAK inhibitor for 2 h reduced the expression of genes encoding COX-2, IL-1β, and TNF-α induced by CTS-associated inflammation and decreased phosphorylation of FAK, p-38, ERK, and JNK. Pretreatment with FAK, p-38, ERK, and JNK inhibitors markedly suppressed COX-2 and IL-1β protein expression. In conclusion, FAK appears to regulate inflammation in chondrocytes under CTS via MAPK pathways.

Synthesis and reception of prostaglandins in corpora lutea of domestic cat and lynx.

PubMed

Zschockelt, Lina; Amelkina, Olga; Siemieniuch, Marta J; Kowalewski, Mariusz P; Dehnhard, Martin; Jewgenow, Katarina; Braun, Beate C

2016-08-01

Felids show different reproductive strategies related to the luteal phase. Domestic cats exhibit a seasonal polyoestrus and ovulation is followed by formation of corpora lutea (CL). Pregnant and non-pregnant cycles are reflected by diverging plasma progesterone (P4) profiles. Eurasian and Iberian lynxes show a seasonal monooestrus, in which physiologically persistent CL (perCL) support constantly elevated plasma P4 levels. Prostaglandins (PGs) represent key regulators of reproduction, and we aimed to characterise PG synthesis in feline CL to identify their contribution to the luteal lifespan. We assessed mRNA and protein expression of PG synthases (PTGS2/COX2, PTGES, PGFS/AKR1C3) and PG receptors (PTGER2, PTGER4, PTGFR), and intra-luteal levels of PGE2 and PGF2α Therefore, CL of pregnant (pre-implantation, post-implantation, regression stages) and non-pregnant (formation, development/maintenance, early regression, late regression stages) domestic cats, and prooestrous Eurasian (perCL, pre-mating) and metoestrous Iberian (perCL, freshCL, post-mating) lynxes were investigated. Expression of PTGS2/COX2, PTGES and PTGER4 was independent of the luteal stage in the investigated species. High levels of luteotrophic PGE2 in perCL might be associated with persistence of luteal function in lynxes. Signals for PGFS/AKR1C3 expression were weak in mid and late luteal stages of cats but were absent in lynxes, concomitant with low PGF2α levels in these species. Thus, regulation of CL regression by luteal PGF2α seems negligible. In contrast, expression of PTGFR was evident in nearly all investigated CL of cat and lynxes, implying that luteal regression, e.g. at the end of pregnancy, is triggered by extra-luteal PGF2α. © 2016 Society for Reproduction and Fertility.

COX-2 and SCD, markers of inflammation and adipogenesis, are related to disease activity in Graves' ophthalmopathy.

PubMed

Vondrichova, Tereza; de Capretz, Annika; Parikh, Hemang; Frenander, Christofer; Asman, Peter; Aberg, Magnus; Groop, Leif; Hallengren, Bengt; Lantz, Mikael

2007-06-01

Inflammation and adipogenesis are two parallel processes with increased activity in severe Graves' ophthalmopathy. The aim of this work was to define target genes for therapeutic intervention in adipogenesis and inflammation in Graves' ophthalmopathy. Orbital tissue was obtained from patients with ophthalmopathy in acute or chronic phase undergoing orbital surgery to study gene expression followed by the study of potential intervention mechanisms in preadipocytes. Clinic of Endocrinology, University Hospital, Malmö, Sweden. Patients in acute severe or in chronic phase of ophthalmopathy. Lateral orbital decompression in acute phase and restorative surgery in chronic phase. In vitro treatment of preadipocytes with rosiglitazone and diclofenac. Gene expression in intraorbital tissue or preadipocytes and differentiation of preadipocytes. A marker of adipose tissue, stearoyl-coenzyme A desaturase (SCD), and the proinflammatory gene, cyclooxygenase-2 (COX-2), were overexpressed in patients in active phase compared to the chronic phase of ophthalmopathy. In growth-arrested preadipocytes stimulated with rosiglitazone, COX-2 expression increased temporarily within 1 hour and decreased to undetectable levels after 48 hours. In contrast, SCD and peroxisome proliferator-activated receptor-gamma (PPAR-gamma) expression increased continuously from day 2 to day 7 during adipogenesis. Diclofenac, an inhibitor of cyclooxygenases with antagonistic effects on PPAR-gamma, reduced the number of mature adipocytes by approximately 50%. We conclude that inflammation and adipogenesis decrease with a decrease in activity of ophthalmopathy and that the nonsteroidal antiinflammatory drug diclofenac inhibits adipogenesis. This may represent a putative future treatment of endocrine ophthalmopathy.

Naproxen sodium decreases prostaglandins secretion from cultured human endometrial stromal cells modulating metabolizing enzymes mRNA expression.

PubMed

Carrarelli, Patrizia; Funghi, Lucia; Bruni, Simone; Luisi, Stefano; Arcuri, Felice; Petraglia, Felice

2016-01-01

Dysmenorrhea, defined as painful cramps occurring immediately before or during the menstrual period, is a common symptom of different gynecological diseases. An acute uterine inflammatory response driven by prostaglandins (PGs) is responsible for painful symptoms. Progesterone withdrawal is responsible for activation of cyclooxygenase (COX-2) enzyme and decrease of hydroxyprostaglandin dehydrogenase (HPDG) with consequent increased secretion of PGs secretion, inducing uterine contractility and pain. The most widely used drugs for the treatment of pelvic pain associated with menstrual cycle are non steroidal anti-inflammatory drugs (NSAIDs). The uterine site of action of these drugs is still not defined and the present study evaluated the effect of naproxen sodium in cultured human endometrial stromal cells (HESC) collected from healthy women. PGE2 release was measured by ELISA; COX-2 and HPDG mRNA expression were assessed by qRT-PCR. Naproxen sodium did not affect HESC vitality. Naproxen sodium significantly decreased PGE2 secretion (p < 0.01) and COX-2 mRNA expression (p < 0.01). TNF-α induced PGE2 release was reduced in presence of naproxen sodium (p < 0.05), in association with decreased COX-2 and increased HPDG mRNAs expression. Naproxen sodium decreases endometrial PGE2 release induced by inflammatory stimulus acting on endometrial COX-2 and HPDG expression, suggesting endometrial synthesis of prostaglandins as a possible target for reduction of uterine inflammatory mechanism in dysmenorrhea.

VEGF expression and the effect of NSAIDs on ascites cell proliferation in the hen model of ovarian cancer.

PubMed

Urick, M E; Giles, J R; Johnson, P A

2008-09-01

We aimed to determine the expression of vascular endothelial growth factor (VEGF) and the effect of nonsteroidal anti-inflammatory drugs (NSAIDs) on the proliferation of cells isolated from ascites in the hen model of ovarian cancer. Ovarian tumor and normal ovary were collected from hens and ascites cells were isolated from hens with ovarian cancer. Quantitative real-time PCR was used to quantify mRNA expression. Immunohistochemical and/or Western blot analyses were used to localize protein expression in ovarian tumors, normal ovaries, and ascites cells. Cells were treated with a nonspecific, COX-1-specific, or COX-2-specific NSAID and proliferation was determined. VEGF mRNA was increased in ascites cells and there was a trend for a correlation between VEGF mRNA in ascites cells and ascites volume. VEGF protein was localized to theca cells of normal ovaries, in glandular areas of tumors, and to the cytoplasm of ascites cells. Aspirin and a COX-1-specific inhibitor decreased the proliferation of ascites cells, whereas a COX-2-specific inhibitor did not. VEGF may play a role in ovarian cancer progression in the hen and the proliferation of ascites cells can be decreased by targeting the COX-1 but not COX-2 pathway.

Celastrol, an inhibitor of heat shock protein 90β potently suppresses the expression of matrix metalloproteinases, inducible nitric oxide synthase and cyclooxygenase-2 in primary human osteoarthritic chondrocytes.

PubMed

Ding, Qian-Hai; Cheng, Ye; Chen, Wei-Ping; Zhong, Hui-Ming; Wang, Xiang-Hua

2013-05-15

Overexpression of matrix metalloproteinases (MMPs), inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) have long been suggested to play crucial roles in the progression of osteoarthritis. Studies have showed that selective MMPs, iNOS and COX-2 inhibitors possess great potential as chondroprotective agents for osteoarthritis. Therefore, there have been intensive efforts to develop novel natural compounds that target MMPs, iNOS and COX-2 activation. As interleukin-1β (IL-1β) is one of the key proinflammatory cytokines contributing to the progression in osteoarthritis, we investigated the effect of celastrol, a triterpenoid compound extracted from the Chinese herb Tript erygium wilfordii Hook F, in neutralizing the inflammatory effects of IL-1β on MMPs, iNOS and COX-2 expression as well as nitric oxide (NO) and prostaglandin E2 (PGE2) production. Protein expression was detected by Western blotting or by enzyme-linked immunosorbent assay (ELISA); messenger RNA (mRNA) expression was examined by real-time reverse transcription-polymerase chain reaction analysis and the involvement of signal pathway was assessed by transient transfection and luciferase activity assay. We found that treatment of primary human osteoarthritic chondrocytes with various concentrations of celastrol resulted in striking decrease in the expression of MMP-1, MMP-3, MMP-13, iNOS-2 and COX-2. In addition, celastrol treatment of cells also inhibited the activation of nuclear factor-kappa B (NF-kappaB). Taken together, we provide evidence that celastrol can protect human chondrocytes by downregulating the expression of MMPs, iNOS and COX-2. We suggest that celastrol could be a useful agent for prevention and treatment of osteoarthritis. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

The value of cyclooxygenase-2 expression in differentiating between early melanomas and histopathologically difficult types of benign human skin lesions.

PubMed

Kuźbicki, Łukasz; Lange, Dariusz; Strączyńska-Niemiec, Anita; Chwirot, Barbara W

2012-02-01

Early cutaneous melanomas may present a substantial diagnostic challenge. We have already reported that expression of cyclooxygenase-2 (COX-2) may be useful for differentiating between cutaneous melanomas and naevi. The purpose of this study was to examine the value of COX-2 in a challenging task of differential diagnosis of early melanomas and melanocytic naevi considered by histopathologists as morphologically difficult to unequivocally diagnose as benign lesions. The material for the study comprised formalin-fixed paraffin-embedded samples of 46 naevi (including 27 cases of dysplastic, Spitz and Reed naevi) and 30 early human cutaneous melanomas. The expression of COX-2 was detected immunohistochemically. Melanomas expressed COX-2 significantly more strongly compared with naevi. The test, on the basis of determination of the percentage fractions of COX-2-positive cells, allows for differentiation of early skin melanomas and naevi with high sensitivity and specificity. Receiver operating characteristic analysis of the test results yielded areas under receiver operating characteristics curves (AUC)=0.946±0.030 for central regions and AUC=0.941±0.031 for the peripheries of the lesions. The performance of the test in differentiating between melanomas and the naevi group comprising dysplastic, Spitz and Reed naevi was also good, with AUC=0.933±0.034 and 0.923±0.037 for the central and the border regions of the lesions, respectively. Using a more complex diagnostic algorithm also accounting for the staining intensity did not result in an improvement in the resolving power of the assay. A diagnostic algorithm using differences in the percentage fractions of cells expressing COX-2 may serve as a useful tool in aiding the differential diagnosis of 'histopathologically difficult' benign melanocytic skin lesions and early melanomas.

Sulforaphane suppresses ultraviolet B-induced inflammation in HaCaT keratinocytes and HR-1 hairless mice.

PubMed

Shibata, Akira; Nakagawa, Kiyotaka; Yamanoi, Hiroko; Tsuduki, Tsuyoshi; Sookwong, Phumon; Higuchi, Ohki; Kimura, Fumiko; Miyazawa, Teruo

2010-08-01

Ultraviolet B (UVB) irradiation induces skin damage and inflammation. One way to reduce the inflammation is via the use of molecules termed photochemopreventive agents. Sulforaphane (4-methylsulfinylbutyl isothiocyanate, SF), which is found in cruciferous vegetables, is known for its potent physiological properties. This study was designed to evaluate the effect of SF on skin inflammation in vitro and in vivo. In in vitro study using immortalized human keratinocytes (HaCaT), UVB caused marked inflammatory responses [i.e., decrease of HaCaT viability and increase of production of an inflammatory marker interleukin-6 (IL-6)]. SF recovered the cell proliferation and suppressed the IL-6 production. These anti-inflammatory effects of SF were explained by its ability to reduce UVB-induced inflammatory gene expressions [IL-6, IL-1beta and cyclooxgenase-2 (COX-2)]. Because SF seems to have an impact on COX-2 expression, we focused on COX-2 and found that SF reduced UVB-induced COX-2 protein expression. In support of this, PGE(2) released from HaCaT was suppressed by SF. Western blot analysis revealed that SF inhibited p38, ERK and SAPK/JNK activation, indicating that the inhibition of mitogen-activated protein kinases (MAPK) by SF would attenuate the expression of inflammatory mediators (e.g., COX-2), thereby reducing inflammatory responses. Moreover, we conducted skin thickening assay using HR-1 hairless mice and found that UVB-induced skin thickness, COX-2 protein expression and hyperplasia were all suppressed by feeding SF to the mice. These results suggest that SF has a potential use as a compound for protection against UVB-induced skin inflammation. Copyright 2010 Elsevier Inc. All rights reserved.

Brain-targeted ACE2 overexpression attenuates neurogenic hypertension by inhibiting COX mediated inflammation

PubMed Central

Sriramula, Srinivas; Xia, Huijing; Xu, Ping; Lazartigues, Eric

2014-01-01

Overactivity of the renin angiotensin system (RAS), oxidative stress, and cyclooxygenases (COX) in the brain are implicated in the pathogenesis of hypertension. We previously reported that Angiotensin-Converting Enzyme 2 (ACE2) overexpression in the brain attenuates the development of DOCA-salt hypertension, a neurogenic hypertension model with enhanced brain RAS and sympathetic activity. To elucidate the mechanisms involved, we investigated whether oxidative stress, mitogen activated protein kinase signaling and cyclooxygenase (COX) activation in the brain are modulated by ACE2 in neurogenic hypertension. DOCA-salt hypertension significantly increased expression of Nox-2 (+61 ±5 %), Nox-4 (+50 ±13 %) and nitrotyrosine (+89 ±32 %) and reduced activity of the antioxidant enzymes, catalase (−29 ±4 %) and SOD (−31 ±7 %), indicating increased oxidative stress in the brain of non-transgenic mice. This increased oxidative stress was attenuated in transgenic mice overexpressing ACE2 in the brain. DOCA-salt-induced reduction of nNOS expression (−26 ±7 %) and phosphorylated eNOS/total eNOS (−30 ±3 %), and enhanced phosphorylation of Akt and ERK1/2 in the paraventricular nucleus (PVN), were reversed by ACE2 overexpression. In addition, ACE2 overexpression blunted the hypertension-mediated increase in gene and protein expression of COX-1 and COX-2 in the PVN. Furthermore, gene silencing of either COX-1 or COX-2 in the brain, reduced microglial activation and accompanied neuro-inflammation, ultimately attenuating DOCA-salt hypertension. Together, these data provide evidence that brain ACE2 overexpression reduces oxidative stress and COX-mediated neuro-inflammation, improves anti-oxidant and nitric oxide signaling, and thereby attenuates the development of neurogenic hypertension. PMID:25489058

Combination of a poxvirus-based vaccine with a cyclooxygenase-2 inhibitor (celecoxib) elicits antitumor immunity and long-term survival in CEA.Tg/MIN mice.

PubMed

Zeytin, Hasan E; Patel, Arti C; Rogers, Connie J; Canter, Daniel; Hursting, Stephen D; Schlom, Jeffrey; Greiner, John W

2004-05-15

The present study was designed to determine whether: (a) chronic administration of dietary celecoxib (Celebrex), a potent nonsteroidal anti-inflammatory drug, which targets the cyclooxygenase-2 (COX-2) enzyme, negatively impacts host immunity; and (b) celecoxib can be coupled with a poxvirus-based vaccine to impact tumor burden in a murine tumor model of spontaneous adenomatous polyposis coli. Naive mice fed the celecoxib-supplemented diets developed eosinophilia with lowered plasma prostaglandin E(2) levels and reduced COX-2 mRNA expression levels in their splenic T cells. Responses of splenic T, B, and natural killer cells to broad-based and antigen-specific stimuli were, for the most part, unchanged in those mice as well as COX-2 knockout mice; exceptions included: (a) reduced IFN-gamma production by concanavalin A- or antigen-stimulated T cells; and (b) heightened lipopolysaccharide response of naive B cells from mice fed a diet supplemented with 1000 ppm of celecoxib. When transgenic mice that express the human carcinoembryonic antigen (CEA) gene (CEA transgenic) were bred with mice bearing a mutation in the Apc(Delta850) gene (multiple intestinal neoplasia mice), the progeny (CEA transgenic/multiple intestinal neoplasia) spontaneously develop multiple intestinal neoplasms that overexpress CEA and COX-2. Beginning at 30 days of age, the administration of a diversified prime/boost recombinant CEA-poxvirus-based vaccine regimen or celecoxib (1000 ppm)-supplemented diet reduced the number of intestinal neoplasms by 54% and 65%, respectively. Combining the CEA-based vaccine with the celecoxib-supplemented diet reduced tumor burden by 95% and significantly improved overall long-term survival. Both tumor reduction and improved overall survival were achieved without any evidence of autoimmunity directed at CEA-expressing or other normal tissues. Celecoxib is prescribed for the treatment of familial adenomatous polyposis in humans, and the CEA-based vaccines have been well tolerated and capable of eliciting anti-CEA host immune responses in early clinical studies. The results suggest that the administration of a recombinant poxvirus-based vaccine is compatible with celecoxib, and this combined chemoimmuno-based approach might lead to an additive therapeutic antitumor benefit not only in patients diagnosed with familial adenomatous polyposis but, perhaps, in other preventive settings in which COX-2 overexpression is associated with progression from premalignancy to neoplasia.

Cyclooxygenase-2 inhibitor enhances the efficacy of a breast cancer vaccine: role of IDO.

PubMed

Basu, Gargi D; Tinder, Teresa L; Bradley, Judy M; Tu, Tony; Hattrup, Christine L; Pockaj, Barbara A; Mukherjee, Pinku

2006-08-15

We report that administration of celecoxib, a specific cyclooxygenase-2 (COX-2) inhibitor, in combination with a dendritic cell-based cancer vaccine significantly augments vaccine efficacy in reducing primary tumor burden, preventing metastasis, and increasing survival. This combination treatment was tested in MMTV-PyV MT mice that develop spontaneous mammary gland tumors with metastasis to the lungs and bone marrow. Improved vaccine potency was associated with an increase in tumor-specific CTLs. Enhanced CTL activity was attributed to a significant decrease in levels of tumor-associated IDO, a negative regulator of T cell activity. We present data suggesting that inhibiting COX-2 activity in vivo regulates IDO expression within the tumor microenvironment; this is further corroborated in the MDA-MB-231 human breast cancer cell line. Thus, a novel mechanism of COX-2-induced immunosuppression via regulation of IDO has emerged that may have implications in designing future cancer vaccines.

Sulforaphane inhibits IL-1β-induced proliferation of rheumatoid arthritis synovial fibroblasts and the production of MMPs, COX-2, and PGE2.

PubMed

Choi, Yun Jung; Lee, Won-Seok; Lee, Eun-Gyeong; Sung, Myung-Soon; Yoo, Wan-Hee

2014-10-01

This study was performed to define the effects of sulforaphane on interleukin-1β (IL-1β)-induced proliferation of rheumatoid arthritis synovial fibroblasts (RASFs), the expression of matrix metalloproteinases (MMPs) and cyclooxygenase (COX), and the production of prostaglandin E2 (PGE2) by RASFs. The proliferation of RASFs was evaluated with CCK-8 reagent in the presence of IL-1β with/without sulforaphane. The expression of MMPs, tissue inhibitor of metalloproteinase-1, COXs, intracellular mitogen-activated protein kinase signalings, including p-ERK, p-p38, p-JNK, and nuclear factor-kappaB (NF-kB), and the production of PGE2 were examined by Western blotting or semi-quantitative RT-PCR and ELISA. Sulforaphane inhibits unstimulated and IL-1β-induced proliferation of RASFs; the expression of MMP-1, MMP-3, and COX-2 mRNA and protein; and the PGE2 production induced by IL-1β. Sulforaphane also inhibits the phosphorylation of ERK-1/2, p-38, and JNK and activation of NF-kB by IL-1β. These results indicate that sulforaphane inhibits the proliferation of synovial fibroblasts, the expression of MMPs and COX-2, and the production of PGE2, which are involved in synovitis and destruction of RA, and suggest that sulforaphane might be a new therapeutic agent for RA.

Baicalein inhibits pulmonary carcinogenesis-associated inflammation and interferes with COX-2, MMP-2 and MMP-9 expressions in-vivo

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chandrashekar, Naveenkumar; Selvamani, Asokkumar; Subramanian, Raghunandhakumar

2012-05-15

The objective of the present study is to investigate the therapeutic efficacy of baicalein (BE) on inflammatory cytokines, which is in line with tumor invasion factors and antioxidant defensive system during benzo(a)pyrene [B(a)P] (50 mg/kg body weight) induced pulmonary carcinogenesis in Swiss albino mice. After experimental period, increased levels of total and differential cell count in bronchoalveolar lavage fluid were observed. Accompanied by marked increase in immature mast cell by toluidine blue staining and mature mast cell by safranin–alcian blue staining in B(a)P-induced lung cancer bearing animals. Protein expression levels studied by immunohistochemistry and immunoblot analysis of cytokines such asmore » tumor necrosis factor-α, interleukin-1β and inducible nitric oxide synthase were also found to be significantly increased in lung cancer bearing animals. B(a)P-exposed mice lung exhibits activated expression of nuclear transcription factor kappa-B as confirmed by immunofluorescence and immunoblot analysis. Administration of BE (12 mg/kg body weight) significantly counteracted all the above deleterious changes. Moreover, assessment of tumor invasion factors on protein levels by immunoblot and mRNA expression levels by RT-PCR revealed that BE treatment effectively negates B(a)P-induced upregulated expression of matrix metalloproteinase-2, matrix metalloproteinase-9 and cyclo-oxygenase-2. Further analysis of lipid peroxidation markers such as thiobarbituric acid reactive substances, hydro-peroxides and antioxidants such as glutathione-S-transferase and reduced glutathione in lung tissue was carried out to substantiate the antioxidant effect of BE. The chemotherapeutic effect observed in the present study is attributed to the potent anti-inflammatory and antioxidant potential by BE against pulmonary carcinogenesis. -- Highlights: ► BE treatment protects from inflammatory cells and mast-cells accumulation in lungs. ► BE altered the expressions of TNF-α, IL-1β, i-NOS and NF-κBp65 at protein levels. ► BE modulates the expressions of MMP-2, MMP-9 and COX-2 at protein and mRNA levels. ► BE decreases LPO levels and enhances antioxidant status.« less

Prostaglandin E(2) and insulin-like growth factor I interact to enhance proliferation of theca externa cells from chicken prehierarchical follicles.

PubMed

Jia, Yudong; Lin, Jinxing; Mi, Yuling; Zhang, Caiqiao

2013-10-01

The interactive effect of insulin-like growth factor I (IGF-I) and prostaglandin E2 (PGE2) on the proliferation of theca externa cells (TECs) was investigated in the prehierarchical small yellow follicles of laying hens. IGF-I manifested a proliferating effect like PGE2 on TECs, but this stimulating effect was restrained by AG1024 (IGF-IR inhibitor), KP372-1 (PKB/AKT inhibitor) or NS398 (COX-2 inhibitor). AG1024, KP372-1 or NS398 abolished IGF-I-stimulated COX-2 expression and PGE2 production. Meanwhile, KP372-1, NS398 or AG1024 depressed the PGE2-stimulated expression of COX-2 and IGF-IR mRNA. Therefore, the IGF-I receptor pathway up-regulates COX-2 expression and PGE2 synthesis via PKB signaling cascade, and then PGE2 stimulates IGF-IR mRNA expression to promote TEC proliferation in an autocrine pattern. Overall, the reciprocal stimulation of intracellular PGE2 and IGF-I may enhance TEC proliferation and facilitate the development of chicken prehierarchical follicles. Copyright © 2013 Elsevier Inc. All rights reserved.

The Effect of Cyclooxygenase Inhibition on Tendon-Bone Healing in an In Vitro Coculture Model

PubMed Central

Schwarting, Tim; Pretzsch, Sebastian; Debus, Florian; Ruchholtz, Steffen; Lechler, Philipp

2015-01-01

The effects of cyclooxygenase (COX) inhibition following the reconstruction of the anterior cruciate ligament remain unclear. We examined the effects of selective COX-2 and nonselective COX inhibition on bone-tendon integration in an in vitro model. We measured the dose-dependent effects of ibuprofen and parecoxib on the viability of lipopolysaccharide- (LPS-) stimulated and unstimulated mouse MC3T3-E1 and 3T3 cells, the influence on gene expression at the osteoblast, interface, and fibroblast regions measured by quantitative PCR, and cellular outgrowth assessed on histological sections. Ibuprofen led to a dose-dependent suppression of MC3T3 cell viability, while parecoxib reduced the viability of 3T3 cultures. Exposure to ibuprofen significantly suppressed expression of Alpl (P < 0.01), Bglap (P < 0.001), and Runx2 (P < 0.01), and although parecoxib reduced expression of Alpl (P < 0.001), Fmod (P < 0.001), and Runx2 (P < 0.01), the expression of Bglap was increased (P < 0.01). Microscopic analysis showed a reduction in cellular outgrowth in LPS-stimulated cultures following exposure to ibuprofen and parecoxib. Nonselective COX inhibition and the specific inhibition of COX-2 led to region-specific reductions in markers of calcification and cell viability. We suggest further in vitro and in vivo studies examining the biologic and biomechanical effects of selective and nonselective COX inhibition. PMID:26063979

UVB light upregulates prostaglandin synthases and prostaglandin receptors in mouse keratinocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Black, Adrienne T.; Gray, Joshua P.; Shakarjian, Michael P.

Prostaglandins belong to a class of cyclic lipid-derived mediators synthesized from arachidonic acid via COX-1, COX-2 and various prostaglandin synthases. Members of this family include prostaglandins such as PGE{sub 2}, PGF{sub 2{alpha}}, PGD{sub 2} and PGI{sub 2} (prostacyclin) as well as thromboxane. In the present studies we analyzed the effects of UVB on prostaglandin production and prostaglandin synthase expression in primary cultures of undifferentiated and calcium-differentiated mouse keratinocytes. Both cell types were found to constitutively synthesize PGE{sub 2}, PGD{sub 2} and the PGD{sub 2} metabolite PGJ{sub 2}. Twenty-four hours after treatment with UVB (25 mJ/cm{sup 2}), production of PGE{sub 2}more » and PGJ{sub 2} increased, while PGD{sub 2} production decreased. This was associated with increased expression of COX-2 mRNA and protein. UVB (2.5-25 mJ/cm{sup 2}) also caused marked increases in mRNA expression for the prostanoid synthases PGDS, mPGES-1, mPGES-2, PGFS and PGIS, as well as expression of receptors for PGE{sub 2} (EP1 and EP2), PGD{sub 2} (DP and CRTH2) and prostacyclin (IP). UVB was more effective in inducing COX-2 and DP in differentiated cells and EP1 and IP in undifferentiated cells. UVB readily activated keratinocyte PI-3-kinase (PI3K)/Akt, JNK and p38 MAP signaling pathways which are known to regulate COX-2 expression. While inhibition of PI3K suppressed UVB-induced mPGES-1 and CRTH2 expression, JNK inhibition suppressed mPGES-1, PGIS, EP2 and CRTH2, and p38 kinase inhibition only suppressed EP1 and EP2. These data indicate that UVB modulates expression of prostaglandin synthases and receptors by distinct mechanisms. Moreover, both the capacity of keratinocytes to generate prostaglandins and their ability to respond to these lipid mediators are stimulated by exposure to UVB.« less

Vitamin D Inhibits COX-2 Expression and Inflammatory Response by Targeting Thioesterase Superfamily Member 4*

PubMed Central

Wang, Qingsong; He, Yuhu; Shen, Yujun; Zhang, Qianqian; Chen, Di; Zuo, Caojian; Qin, Jing; Wang, Hui; Wang, Junwen; Yu, Ying

2014-01-01

Inadequate vitamin D status has been linked to increased risk of type 2 diabetes and cardiovascular disease. Inducible cyclooxygenase (COX) isoform COX-2 has been involved in the pathogenesis of such chronic inflammatory diseases. We found that the active form of vitamin D, 1,25(OH)2D produces dose-dependent inhibition of COX-2 expression in murine macrophages under both basal and LPS-stimulated conditions and suppresses proinflammatory mediators induced by LPS. Administration of 1,25(OH)2D significantly alleviated local inflammation in a carrageenan-induced paw edema mouse model. Strikingly, the phosphorylation of both Akt and its downstream target IκBα in macrophages were markedly suppressed by 1,25(OH)2D in the presence and absence of LPS stimulation through up-regulation of THEM4 (thioesterase superfamily member 4), an Akt modulator protein. Knockdown of both vitamin D receptor and THEM4 attenuated the inhibitory effect of 1,25(OH)2D on COX-2 expression in macrophages. A functional vitamin D-responsive element in the THEM4 promoter was identified by chromatin immunoprecipitation and luciferase reporter assay. Our results indicate that vitamin D restrains macrophage-mediated inflammatory processes by suppressing the Akt/NF-κB/COX-2 pathway, suggesting that vitamin D supplementation might be utilized for adjunctive therapy for inflammatory disease. PMID:24619416

The shunt from the cyclooxygenase to lipoxygenase pathway in human osteoarthritic subchondral osteoblasts is linked with a variable expression of the 5-lipoxygenase-activating protein.

PubMed

Maxis, Kelitha; Delalandre, Aline; Martel-Pelletier, Johanne; Pelletier, Jean-Pierre; Duval, Nicolas; Lajeunesse, Daniel

2006-01-01

Osteoarthritis (OA) is characterized by articular cartilage degradation and hypertrophic bone changes with osteophyte formation and abnormal bone remodeling. Two groups of OA patients were identified via the production of variable and opposite levels of prostaglandin E2 (PGE2) or leukotriene B4 (LTB4) by subchondral osteoblasts, PGE2 levels discriminating between low and high subgroups. We studied whether the expression of 5-lipoxygenase (5-LO) or 5-LO-activating protein (FLAP) is responsible for the shunt from prostaglandins to leukotrienes. FLAP mRNA levels varied in low and high OA groups compared with normal, whereas mRNA levels of 5-LO were similar in all osteoblasts. Selective inhibition of cyclooxygenase-2 (COX-2) with NS-398-stimulated FLAP expression in the high OA osteoblasts subgroup, whereas it was without effect in the low OA osteoblasts subgroup. The addition of PGE2 to the low OA osteoblasts subgroup decreased FLAP expression but failed to affect it in the high OA osteoblasts subgroup. LTB4 levels in OA osteoblasts were stimulated about twofold by 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) plus transforming growth factor-beta (TGF-beta), a situation corresponding to their effect on FLAP mRNA levels. Treatments with 1,25(OH)2D3 and TGF-beta also modulated PGE2 production. TGF-beta stimulated PGE2 production in both OA osteoblast groups, whereas 1,25(OH)2D3 alone had a limited effect but decreased the effect of TGF-beta in the low OA osteoblasts subgroup. This modulation of PGE2 production was mirrored by the synthesis of COX-2. IL-18 levels were only slightly increased in a subgroup of OA osteoblasts compared with normal; however, no relationship was observed overall between IL-18 and PGE2 levels in normal and OA osteoblasts. These results suggest that the shunt from the production of PGE2 to LTB4 is through regulation of the expression of FLAP, not 5-LO, in OA osteoblasts. The expression of FLAP in OA osteoblasts is also modulated differently by 1,25(OH)2D3 and TGF-beta depending on their endogenous low and high PGE2 levels.

Curcumin attenuates inflammatory response in IL-1beta-induced human synovial fibroblasts and collagen-induced arthritis in mouse model.

PubMed

Moon, Dong-Oh; Kim, Mun-Ok; Choi, Yung Hyun; Park, Yung-Min; Kim, Gi-Young

2010-05-01

Curcumin, a major component of turmeric, has been shown to exhibit anti-oxidant and anti-inflammatory activities. The present study was performed to determine whether curcumin is efficacious against both collagen-induced arthritis (CIA) in mice and IL-1beta-induced activation in fibroblast-like synoviocytes (FLSs). DBA/1 mice were immunized with bovine type II collagen (CII) and treated with curcumin every other day for 2weeks after the initial immunization. For arthritis, we evaluated the incidence of disease and used an arthritis index based on paw thickness. In vitro proliferation of CII- or concanavalin A-induced splenic T cells was examined using IFN-gamma production. Pro-inflammatory cytokines TNF-alpha and IL-1beta were examined in the mouse ankle joint and serum IgG1 and IgG2a isotypes were analyzed. The expression levels of prostaglandin E(2) (PGE(2)), cyclooxygenase-2 (COX-2), and matrix metalloproteinases (MMPs) in human FLSs were also determined. The results showed that compared with untreated CIA mice, curcumin-treated mice downregulated clinical arthritis score, the proliferation of splenic T cells, expression levels of TNF-alpha and IL-1beta in the ankle joint, and expression levels of IgG2a in serum. Additionally, by altering nuclear factor (NF)-kappaB transcription activity in FLSs, curcumin inhibited PGE(2) production, COX-2 expression, and MMP secretion. These results suggest that curcumin can effectively suppress inflammatory response by inhibiting pro-inflammatory mediators and regulating humoral and cellular immune responses. Copyright 2010 Elsevier B.V. All rights reserved.

Redox and Reactive Oxygen Species Regulation of Mitochondrial Cytochrome c Oxidase Biogenesis

PubMed Central

Bourens, Myriam; Fontanesi, Flavia; Soto, Iliana C.; Liu, Jingjing

2013-01-01

Abstract Significance: Cytochrome c oxidase (COX), the last enzyme of the mitochondrial respiratory chain, is the major oxygen consumer enzyme in the cell. COX biogenesis involves several redox-regulated steps. The process is highly regulated to prevent the formation of pro-oxidant intermediates. Recent Advances: Regulation of COX assembly involves several reactive oxygen species and redox-regulated steps. These include: (i) Intricate redox-controlled machineries coordinate the expression of COX isoenzymes depending on the environmental oxygen concentration. (ii) COX is a heme A-copper metalloenzyme. COX copper metallation involves the copper chaperone Cox17 and several other recently described cysteine-rich proteins, which are oxidatively folded in the mitochondrial intermembrane space. Copper transfer to COX subunits 1 and 2 requires concomitant transfer of redox power. (iii) To avoid the accumulation of reactive assembly intermediates, COX is regulated at the translational level to minimize synthesis of the heme A-containing Cox1 subunit when assembly is impaired. Critical Issues: An increasing number of regulatory pathways converge to facilitate efficient COX assembly, thus preventing oxidative stress. Future Directions: Here we will review on the redox-regulated COX biogenesis steps and will discuss their physiological relevance. Forthcoming insights into the precise regulation of mitochondrial COX biogenesis in normal and stress conditions will likely open future perspectives for understanding mitochondrial redox regulation and prevention of oxidative stress. Antioxid. Redox Signal. 19, 1940–1952. PMID:22937827

Nuclear Respiratory Factor-1 (NRF-1) Gene Expression in Chronic Kidney Disease Patients Undergoing Hemodialysis and Mitochondrial Oxidative Dysregulation.

PubMed

Hashad, Doaa; Elgohry, Iman; Dwedar, Fatma

2016-11-01

Chronic kidney disease (CKD) is characterized by progressive irreversible deterioration of renal functions. Advanced stages of CKD are associated with oxidative stress due to the imbalance between oxidant production and antioxidant defense mechanisms. Survival of patients with end stage renal diseases is maintained on variable forms of renal replacement therapies (RRT) which include peritoneal dialysis, hemodialysis, and sometimes renal transplantation. In humans, Nuclear Respiratory Factor 1 (NRF-1) gene encodes for a transcription factor that, together with the transcriptional co-activator encoded by Peroxisome Proliferator activated Receptor Gamma coactivator 1 Alpha (PGC1-a) gene, stimulates the expression of a broad set of nuclear genes (as COX6C) which are involved in mitochondrial biogenesis and functions. As mitochondria are considered a major source of reactive oxidant species, the objective of the present study was to assess mitochondrial oxidative dysregulation occurring in chronic kidney disease patients undergoing hemodialysis employing NRF-1 and COX6C genes' expression as an indicator of mitochondrial oxidative metabolism. Forty-nine chronic kidney disease patients undergoing intermittent hemodialysis were included in the present study. A group of thirty-three age- and gender- matched healthy volunteers served as a control group. Assessment of expression of NRF-1 and COX6C genes was performed using quantitative real-time PCR technique. NRF-1 and COX6C expression showed a statistically significant difference between both studied groups being down-regulated in CKD patients. In addition, malondialdehyde (MDA) levels were higher in patients on hemodialysis indicating lipid peroxidation. A negative correlation was detected between MDA level and expression of both NRF-1 and COX6C genes. Chronic kidney disease patients undergoing hemodialysis might be subjected to potential mitochondrial oxidative dysregulation with subsequent possible vascular and tissue injury.

Cloning and expression analysis of innate immune genes from red sea bream to assess different susceptibility to megalocytivirus infection.

PubMed

Jin, J W; Kim, Y C; Hong, S; Kim, M S; Jeong, J B; Jeong, H D

2017-04-01

As suggested by the Office International des Epizooties (OIE), fishes belonging to the genus Oplegnathus are more sensitive to megalocytivirus infection than other fish species including red sea bream (Pagrus major). To assess the roles of the innate immune response to these different susceptibilities, we cloned the genes encoding inflammatory factors including IL-8 and COX-2, and the antiviral factor like Mx from red sea bream for the first time and performed phylogenetic and structural analysis. Analysed expression levels of IL-1β, IL-8 and COX-2 and the antiviral factor like Mx genes performed with in vivo challenge experiment showed no difference in inflammatory gene expression or respiratory burst activity between red sea bream and rock bream (Oplegnathus fasciatus). However, the Mx gene expression levels in red sea bream were markedly higher than those in rock bream, suggesting the importance of type I interferon (IFN)-induced proteins, particularly Mx, during megalocytivirus infection, rather than inflammation-related genes. The in vitro challenge experiments using embryonic primary cultures derived from both fish species showed no difference in cytopathic effects (CPE), viral replication profiles, and inflammatory and Mx gene expression pattern between the two fish species. © 2016 John Wiley & Sons Ltd.

Dual oxidase 1: A predictive tool for the prognosis of hepatocellular carcinoma patients.

PubMed

Chen, Shengsen; Ling, Qingxia; Yu, Kangkang; Huang, Chong; Li, Ning; Zheng, Jianming; Bao, Suxia; Cheng, Qi; Zhu, Mengqi; Chen, Mingquan

2016-06-01

Dual oxidase 1 (DUOX1), which is the main source of reactive oxygen species (ROS) production in the airway, can be silenced in human lung cancer and hepatocellular carcinomas. However, the prognostic value of DUOX1 expression in hepatocellular carcinoma patients is still unclear. We investigated the prognostic value of DUOX1 expression in liver cancer patients. DUOX1 mRNA expression was determined in tumor tissues and non-tumor tissues by real‑time PCR. For evaluation of the prognostic value of DUOX1 expression, Kaplan-Meier method and Cox's proportional hazards model (univariate analysis and multivariate analysis) were employed. A simple risk score was devised by using significant variables obtained from the Cox's regression analysis to further predict the HCC patient prognosis. We observed a reduced DUOX1 mRNA level in the cancer tissues in comparison to the non‑cancer tissues. More importantly, Kaplan-Meier analysis showed that patients with high DUOX1 expression had longer disease-free survival and overall survival compared with those with low expression of DUOX1. Cox's regression analysis indicated that DUOX1 expression, age, and intrahepatic metastasis may be significant prognostic factors for disease-free survival and overall survival. Finally, we found that patients with total scores of >2 and >1 were more likely to relapse and succumb to the disease than patients whose total scores were ≤2 and ≤1. In conclusion, DUOX1 expression in liver tumors is a potential prognostic tool for patients. The risk scoring system is useful for predicting the survival of liver cancer patients after tumor resection.

Involvement of DDAH/ADMA/NOS/cGMP and COX-2/PTGIS/cAMP Pathways in Human Tissue Kallikrein 1 Protecting Erectile Function in Aged Rats

PubMed Central

Tang, Zhe; Rao, Ke; Wang, Tao; Chen, Zhong; Wang, Shaogang; Liu, Jihong; Wang, Daowen

2017-01-01

Our previous studies had reported that Human Tissue Kallikrein 1 (hKLK1) preserved erectile function in aged transgenic rats, while the detailed mechanism of hKLK1 protecting erectile function in aged rats through activation of cGMP and cAMP was not mentioned. To explore the latent mechanism, male wild-type Sprague-Dawley rats (WTR) and transgenic rats harboring the hKLK1 gene (TGR) were fed to 4 and 18 months old and divided into four groups: young WTR (yWTR) as the control, aged WTR (aWTR), aged TGR (aTGR) and aged TGRs with HOE140 (aTGRH). Erectile function of all rats was evaluated by cavernous nerve electrostimulation method and measured by the ratio of intracavernous pressure/ mean arterial pressure (ICP/MAP) in rats. Expression levels of cAMP and cGMP were assessed, and related signaling pathways were detected by western blot, immunohistochemistry and RT-PCR. Our experiment results showed erectile function of the aWTR group and aTGRH group was lower compared with those of other two groups. Also, expression levels of cAMP and cGMP were significantly lower than those of other two groups. Moreover, expressions of related signaling pathways including DDAH/ADMA/NOS/cGMP and COX-2/PTGIS/cAMP were also downregulated in the corpus cavernosum of rats in aWTR group. Our finding revealed hKLK1 played a protective role in age-related ED. The DDAH/ADMA/NOS/cGMP and COX-2/PTGIS/cAMP pathways that were linked to the mechanism hKLK1 could increase the levels of cGMP and cAMP, which might provide novel therapy targets for age-related ED. PMID:28103290

Overexpression of COX-2 and LMP1 are correlated with lymph node in Tunisian NPC patients.

PubMed

Fendri, Ali; Khabir, Abdelmajid; Hadhri-Guiga, Boutheina; Sellami-Boudawara, Tahia; Ghorbel, Abdelmoonem; Daoud, Jamel; Frikha, Mounir; Jlidi, Rachid; Gargouri, Ali; Mokdad-Gargouri, Raja

2008-07-01

Cyclooxygenase 2 (COX-2) an inducible form of COX is frequently up-regulated in many human tumours. The expression of COX-2 in nasopharyngeal carcinoma (NPC) and its relationship to clinicopathological features were studied in Tunisian patients. COX-2 mRNA was detected in 91% of tumour tissues. Immunohistochemical analysis showed that COX-2 protein was strongly detected in tumour cells and the staining was mainly cytoplasmic. In contrast, COX-2 mRNA and protein were very low or undetectable in normal nasopharyngeal mucosa. Our result showed a significant association of COX-2 overexpression with the lymph node involvement, however, no correlation was observed with age, tumour stage, histological type and distant metastasis. Moreover, we showed that all tumour specimens co-overexpressed COX-2 and the EBV oncoprotein LMP1 corroborating the fact that LPM1 is known to induce COX-2. Altogether, our data suggests that the COX-2 is overexpressed in NPC biopsies and that is linked to the lymph node involvement.

Oxymatrine attenuated isoproterenol-induced heart failure in rats via regulation of COX-2/PGI2 pathway.

PubMed

Zhou, Ru; Xu, Qingbin; Xu, Yehua; Xiong, Aiqin; Wang, Yang; Ma, Ping

2016-12-01

Oxymatrine (OMT) is an active constituent of traditional Chinese herb Sophora japonica Ait which has been shown to exert potent anti-inflammatory,anti-oxidant and anti-fibrosis properties. Our previous studies have demonstrated that OMT has protective effects on isoproterenol-induced heart failure in rats through regulation of DDAH/ADMA metabolism pathway.In this study,we further investigated whether OMT could attenuate isoproterenol-induced heart failure through the regulation of COX-2/PGI 2 pathway. Heart failure was induced in Sprague-Dawley rats by 5mg/kg isoproterenol subcutaneous injection for 7days. The rats were maintained on normal diet and randomly divided into five groups: control, isoproterenol, isoproterenol with OMT (50, 100mg/kg), and OMT alone groups (n=12 in each group). Serum brain natruretic peptide (BNP, a heart failure biomarker), histopathological variables, expression of Cytosolic phospholipase A 2 (cPLA 2 ), cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2) and Prostacyclin synthase (PGIS) were analysed. Administration of OMT significantly reduced the increased BNP in plasm of isoproterenol-induced rats, attenuated cardiac fibrosis,suppressed overexpression of myocardial COX-1 expression, up-regulated COX-2 and PGIS expression, but had no effects on isoproterenol-induced elevated protein cPLA 2 . And compared with control group, any indexes in sham rats treated with OMT (100mg/kg) alone were unaltered. These results demonstrated that OMT has cardioprotective effects on isoproterenol-induced heart failure in rats by regulating COX-2/PGI 2 pathway. Copyright © 2016. Published by Elsevier Masson SAS.

Protein kinase C delta overexpressing transgenic mice are resistant to chemically but not to UV radiation-induced development of squamous cell carcinomas: a possible link to specific cytokines and cyclooxygenase-2.

PubMed

Aziz, Moammir H; Wheeler, Deric L; Bhamb, Bhushan; Verma, Ajit K

2006-01-15

Protein kinase C delta (PKCdelta), a Ca(2+)-independent, phospholipid-dependent serine/threonine kinase, is among the novel PKCs (delta, epsilon, and eta) expressed in mouse epidermis. We reported that FVB/N transgenic mice that overexpress ( approximately 8-fold) PKCdelta protein in basal epidermal cells and cells of the hair follicle are resistant to the development of both skin papillomas and squamous cell carcinoma (SCC) elicited by 7,12-dimethylbenz(a)anthracene initiation and 12-O-tetradecanoylphorbol-13-acetate (TPA) promotion protocol. We now present that PKCdelta overexpression in transgenic mice failed to suppress the induction of SCC developed by repeated exposures to UV radiation (UVR), the environmental carcinogen linked to the development of human SCC. Both TPA and UVR treatment of wild-type mice (a) increased the expression of proliferating cell nuclear antigen (PCNA) and apoptosis; (b) stimulated the expression of cytokines tumor necrosis factor-alpha (TNF-alpha), granulocyte macrophage colony-stimulating factor (GM-CSF), and granulocyte CSF (G-CSF); and (c) increased cyclooxygenase-2 (COX-2) expression and expression of phosphorylated Akt (p-Akt), p38, extracellular signal-regulated kinase-1 (ERK1), and ERK2. PKCdelta overexpression in transgenic mice enhanced TPA-induced but not UVR-induced apoptosis and suppressed TPA-stimulated but not UVR-stimulated levels of cell PCNA, cytokines (TNF-alpha, G-CSF, and GM-CSF), and the expression of COX-2, p-Akt, and p38. The results indicate that UVR-mediated signal transduction pathway to the induction of SCC does not seem to be sensitive to PKCdelta overexpression. The proapoptotic activity of PKCdelta coupled with its ability to suppress TPA-induced expression of proinflammatory cytokines, COX-2 expression, and the phosphorylation of Akt and p38 may play roles in the suppression of TPA-promoted development of SCC.

Curcumin, a Curcuma longa constituent, acts on MAPK p38 pathway modulating COX-2 and iNOS expression in chronic experimental colitis.

PubMed

Camacho-Barquero, Laura; Villegas, Isabel; Sánchez-Calvo, Juan Manuel; Talero, Elena; Sánchez-Fidalgo, Susana; Motilva, Virginia; Alarcón de la Lastra, Catalina

2007-03-01

Ulcerative colitis (UC) is a nonspecific inflammatory disorder characterized by oxidative and nitrosative stress, leucocyte infiltration and up-regulation of pro-inflammatory cytokines. Mitogen-activated protein kinases (MAPKs), such as the p38 and the c-Jun N-terminal kinase (JNK) modulate the transcription of many genes involved in the inflammatory process. Curcumin is a polyphenol derived from Curcuma longa, which is known to have anti-inflammatory activity. The aim of this study was to study the effects and mechanisms of action of curcumin, on chronic colitis in rats. Inflammation response was assessed by histology and myeloperoxidase activity (MPO). We determined the production of Th1 and Th2 cytokines and nitrites in colon mucosa, as well as the expression of inducible nitric oxide synthase (iNOS), cyclo-oxygenase(COX)-1 and-2 by western blotting and inmmunohistochemistry. Finally, we studied the involvement of MAPKs signaling in the protective effect of curcumin in chronic colonic inflammation. Curcumin (50-100 mg/kg/day) were administered by oral gavage 24 h after trinitrobenzensulfonic acid (TNBS) instillation, and daily during 2 weeks before sacrifice. Curcumin significantly attenuated the damage and caused substantial reductions of the rise in MPO activity and tumour necrosis factor alpha (TNF)-alpha. Also curcumine was able to reduce nitrites colonic levels and induced down-regulation of COX-2 and iNOS expression, and a reduction in the activation of p38 MAPK; however, no changes in the activation of JNK could be observed. In conclusion, we suggest that inhibition of p38 MAPK signaling by curcumin could explain the reduced COX-2 and iNOS immunosignals and the nitrite production in colonic mucosa reducing the development of chronic experimental colitis.

Effects of Pleiotrophin on endothelial and inflammatory cells: Pro-angiogenic and anti-inflammatory properties and potential role for vascular bio-prosthesis endothelialization.

PubMed

Palmieri, Daniela; Mura, Marzia; Mambrini, Simone; Palombo, Domenico

2015-09-01

One of the limitations emerged with both synthetic and degradable vascular grafts is the lack of endothelialization after implantation that is known to be the main reason leading to unfavourable outcomes. It emerges the need to find new strategies to promote a rapid endothelialization of the scaffold. Pleiotrophin is a growth/differentiation cytokine for various cell type. We here evaluated the effect of Pleiotrophin on endothelial cells (EC), monocytes and macrophages that have been shown as key cells promoting neovascularization. EA.hy926 endothelial cells, THP-1 monocytes and PMA-differentiated macrophages were treated with Pleiotrophin (10 and 100ng/ml). VEGF, Flk-1, Nrp-1, COX-2, ICAM-1 and TGFβ expression were detected by Western Blot, IL-10, MCP-1 and TNFα levels by ELISA. Chemotaxis was performed in Boyden chambers. Wound healing was performed by scratch wound assay. Pleiotrophin induces in EC the expression of VEGF and its receptors Flk-1 and Nrp-1 and improves the migratory capacity. In THP-1 monocytes, Pleiotrophin induces the expression of VEGF and its receptor Nrp-1 and decreases the levels of COX-2 and TNFα. In PMA-differentiated macrophages COX-2 expression was significantly reduced by Pleiotrophin, while IL-10 and TGFβ were increased. Pleiotrophin acts as an angiogenesis 'driver' by promoting the creation of a pro-angiogenic environment, a migratory behaviour in EC and a pro-regenerative alternative phenotype in macrophages. Our results suggest that Pleiotrophin might be considered for vascular prosthesis engineering. Copyright © 2015 Medical University of Bialystok. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Chamomile, a novel and selective COX-2 inhibitor with anti-inflammatory activity

PubMed Central

Srivastava, Janmejai K; Pandey, Mitali; Gupta, Sanjay

2009-01-01

Aims Inducible cyclooxygenase (COX-2) has been implicated in the process of inflammation and carcinogenesis. Chamomile has long been used in traditional medicine for the treatment of inflammatory diseases. In this study we aimed to investigate whether chamomile interferes with the COX-2 pathway. Main Methods We used lipopolysaccharide (LPS)-activated RAW 264.7 macrophages as an in vitro model for our studies. Key Findings Chamomile treatment inhibited the release of LPS-induced prostaglandin E(2) in RAW 264.7 macrophages. This effect was found to be due to inhibition of COX-2 enzyme activity by chamomile. In addition, chamomile caused reduction in LPS-induced COX-2 mRNA and protein expression, without affecting COX-1 expression. The non-steroidal anti-inflammatory drug, sulindac and a specific COX-2 inhibitor, NS398, were shown to act similarly in LPS-activated RAW 264.7 cells. Our data suggest that chamomile works by a mechanism of action similar to that attributed to non-steroidal anti-inflammatory drugs. Significance These findings add a novel aspect to the biological profile of chamomile which might be important for understanding the usefulness of aqueous chamomile extract in the form of tea in preventing inflammation and cancer. PMID:19788894

Chamomile, a novel and selective COX-2 inhibitor with anti-inflammatory activity.

PubMed

Srivastava, Janmejai K; Pandey, Mitali; Gupta, Sanjay

2009-11-04

Inducible cyclooxygenase (COX-2) has been implicated in the process of inflammation and carcinogenesis. Chamomile has long been used in traditional medicine for the treatment of inflammatory diseases. In this study we aimed to investigate whether chamomile interferes with the COX-2 pathway. We used lipopolysaccharide (LPS)-activated RAW 264.7 macrophages as an in vitro model for our studies. Chamomile treatment inhibited the release of LPS-induced prostaglandin E(2) in RAW 264.7 macrophages. This effect was found to be due to inhibition of COX-2 enzyme activity by chamomile. In addition, chamomile caused reduction in LPS-induced COX-2 mRNA and protein expression, without affecting COX-1 expression. The non-steroidal anti-inflammatory drug, sulindac and a specific COX-2 inhibitor, NS398, were shown to act similarly in LPS-activated RAW 264.7 cells. Our data suggest that chamomile works by a mechanism of action similar to that attributed to non-steroidal anti-inflammatory drugs. These findings add a novel aspect to the biological profile of chamomile which might be important for understanding the usefulness of aqueous chamomile extract in the form of tea in preventing inflammation and cancer.

Induction of cyclooxygenase-2 by ginsenoside Rd via activation of CCAAT-enhancer binding proteins and cyclic AMP response binding protein

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jeong, Hye Gwang; Pokharel, Yuba Raj; Han, Eun Hee

2007-07-20

Panax ginseng is a widely used herbal medicine in East Asia and is reported to have a variety of pharmacological effects against cardiovascular diseases and cancers. Here we show a unique effect of ginsenoside Rd (Rd) on cyclooxygenase-2 (COX-2) expression in RAW264.7 macrophages. Rd (100 {mu}g/ml), but not other ginsenosides induced COX-2 and increased prostaglandin E{sub 2} production. Gel shift and Western blot analyses using nuclear fractions revealed that Rd increased both the DNA binding of and the nuclear levels of CCAAT/enhancer binding protein (C/EBP){alpha}/{beta} and cyclic AMP response element binding protein (CREB), but not of p65, in RAW264.7 cells.more » Moreover, Rd increased the luciferase reporter gene activity in cells transfected with a 574-bp mouse COX-2 promoter construct. Site-specific mutation analyses confirmed that Rd-mediated transcriptional activation of COX-2 gene was regulated by C/EBP and CREB. These results provide evidence that Rd activated C/EBP and CREB, and that the activation of C/EBP and CREB appears to be essential for induction of COX-2 in RAW264.7 cells.« less

Effects of esomeprazole on healing of nonsteroidal anti-inflammatory drug (NSAID)-induced gastric ulcers in the presence of a continued NSAID treatment: Characterization of molecular mechanisms.

PubMed

Fornai, Matteo; Colucci, Rocchina; Antonioli, Luca; Awwad, Oriana; Ugolini, Clara; Tuccori, Marco; Fulceri, Federica; Natale, Gianfranco; Basolo, Fulvio; Blandizzi, Corrado

2011-01-01

Proton pump inhibitors promote ulcer repair in nonsteroidal anti-inflammatory drug (NSAID)-treated patients with ongoing NSAID-induced gastric toxicity, although the underlying mechanisms remain unclear. We examined the healing mechanisms of esomeprazole on NSAID-induced gastric ulcerations in the presence of a continued NSAID treatment. Ulcerations were induced in rats by oral indomethacin (6μmol/kg/day) for 14 days. Indomethacin administration was continued, alone or combined with equivalent acid inhibitory doses of esomeprazole (5μmol/kg/day), lansoprazole (15μmol/kg/day) or famotidine (20μmol/kg/day), for additional 7 days. Stomachs were then processed for: histomorphometric analysis of mucosal injury; mucosal levels of prostaglandin E(2) (PGE(2)) and malondialdehyde (MDA); expression of vascular endothelial growth factor (VEGF), proliferating cell nuclear antigen (PCNA), caspase-3, and cyclooxygenase-2 (COX-2) (Western blot); expression of Ki-67 (immunohistochemistry). Indomethacin for 14 days elicited mucosal damage, reduced PGE(2) levels and increased MDA. After additional 7 days, indomethacin induced the following effects: further enhancement of mucosal damage and MDA content; decrease in PGE(2) levels; increase in COX-2 and activated caspase-3 expression; decrease in VEGF, PCNA and Ki-67 expression. In the presence of indomethacin, esomeprazole and lansoprazole were more effective than famotidine in promoting resolution of mucosal damage. Concomitantly, esomeprazole and lansoprazole, but not famotidine, restored PCNA and Ki-67 expression, and normalized MDA levels. Moreover, esomeprazole, lansoprazole and famotidine partly counteracted caspase-3 activation, without affecting VEGF expression. The healing activity of esomeprazole on indomethacin-induced gastric ulcerations can be ascribed to two mechanisms: (1) acid-dependent reduction of pro-apoptotic signalling; (2) acid-independent restoration of proliferating/repairing pathways. Copyright © 2010 Elsevier Ltd. All rights reserved.

COX-2 and Prostaglandin EP3/EP4 Signaling Regulate the Tumor Stromal Proangiogenic Microenvironment via CXCL12-CXCR4 Chemokine Systems

PubMed Central

Katoh, Hiroshi; Hosono, Kanako; Ito, Yoshiya; Suzuki, Tatsunori; Ogawa, Yasufumi; Kubo, Hidefumi; Kamata, Hiroki; Mishima, Toshiaki; Tamaki, Hideaki; Sakagami, Hiroyuki; Sugimoto, Yukihiko; Narumiya, Shuh; Watanabe, Masahiko; Majima, Masataka

2010-01-01

Bone marrow (BM)–derived hematopoietic cells, which are major components of tumor stroma, determine the tumor microenvironment and regulate tumor phenotypes. Cyclooxygenase (COX)−2 and endogenous prostaglandins are important determinants for tumor growth and tumor-associated angiogenesis; however, their contributions to stromal formation and angiogenesis remain unclear. In this study, we observed that Lewis lung carcinoma cells implanted in wild-type mice formed a tumor mass with extensive stromal formation that was markedly suppressed by COX-2 inhibition, which reduced the recruitment of BM cells. Notably, COX-2 inhibition attenuated CXCL12/CXCR4 expression as well as expression of several other chemokines. Indeed, in a Matrigel model, prostaglandin (PG) E2 enhanced stromal formation and CXCL12/CXCR4 expression. In addition, a COX-2 inhibitor suppressed stromal formation and reduced expression of CXCL12/CXCR4 and a fibroblast marker (S100A4) in a micropore chamber model. Moreover, stromal formation after tumor implantation was suppressed in EP3−/− mice and EP4−/− mice, in which stromal expression of CXCL12/CXCR4 and S100A4 was reduced. The EP3 or EP4 knockout suppressed S100A4+ fibroblasts, CXCL12+, and/or CXCR4+ stromal cells as well. Immunofluorescent analyses revealed that CXCL12+CXCR4+S100A4+ fibroblasts mainly comprised stromal cells and most of these were recruited from the BM. Additionally, either EP3- or EP4-specific agonists stimulated CXCL12 expression by fibroblasts in vitro. The present results address the novel activities of COX-2/PGE2-EP3/EP4 signaling that modulate tumor biology and show that CXCL12/CXCR4 axis may play a crucial role in tumor stromal formation and angiogenesis under the control of prostaglandins. PMID:20110411

Expression levels of brown/beige adipocyte-related genes in fat depots of vitamin A-restricted fattening cattle.

PubMed

Chen, Hsuan-Ju; Ihara, Tsubasa; Yoshioka, Hidetugu; Itoyama, Erina; Kitamura, Shoko; Nagase, Hiroshi; Murakami, Hiroaki; Hoshino, Yoichiro; Murakami, Masaru; Tomonaga, Shozo; Matsui, Tohru; Funaba, Masayuki

2018-06-15

Brown/beige adipocytes dissipate energy as heat. We previously showed that brown/beige adipocytes are present in white adipose tissue (WAT) of fattening cattle. The present study examined the effect of vitamin A restriction on mRNA expression of brown/beige adipocyte-related genes. In Japan, fattening cattle are conventionally fed a vitamin A-restricted diet to improve beef marbling. Twelve Japanese Black steers aged 10 months were fed control feed (n=6) or vitamin A-restricted feed (n=6) for 20 months. Subcutaneous WAT (scWAT) and mesenteric WAT (mesWAT) were collected, and mRNA expression levels of molecules related to function of brown/beige adipocytes (Ucp1, Cidea, Dio2, Cox7a and Cox8b) as well as transcriptional regulators related to brown/beige adipogenesis (Zfp516, Nfia, Prdm16, and Pgc-1α) were evaluated. The vitamin A restriction significantly increased or tended to increase expression levels of Cidea and Pgc-1α in scWAT, and Cidea, Dio2, and Nfia in mesWAT. Previous studies revealed that the bone morphogenetic protein (BMP) pathway was responsible for commitment of mesenchymal stem cells to brown/beige adipocyte-lineage cells. The vitamin A restriction increased expression of Bmp7 and some Bmp receptors in WAT. The interrelationship between gene expression levels indicated that expression levels of Nfia, Prdm16, and Pgc-1α were closely related to those of genes related to function of brown/beige adipocytes in scWAT. Also, expression levels of Nfia, Prdm16, and Pgc-1α were highly correlated with those of Alk3 in scWAT. In summary, the present results suggest that the vitamin A restriction increases the number or activity of brown/beige adipocytes through regulatory expression of transcriptional regulators to induce brown/beige adipogenesis especially in scWAT of fattening cattle, which may be governed by the Bmp pathway.

Anti-inflammatory effects of shea butter through inhibition of iNOS, COX-2, and cytokines via the Nf-κB pathway in LPS-activated J774 macrophage cells.

PubMed

Verma, Nandini; Chakrabarti, Rina; Das, Rakha H; Gautam, Hemant K

2012-01-12

Shea butter is traditionally used in Africa for its anti-inflammatory and analgesic effects. In this study we explored the anti-inflammatory activities of the methanolic extract of shea butter (SBE) using lipopolysaccharide (LPS)-induced murine macrophage cell line J774. It was observed that SBE significantly reduced the levels of LPS-induced nitric oxide, Tumor necrosis factor-α (TNF-α), interleukins, 1β (IL-1β), and -12 (IL-12) in the culture supernatants in a dose dependent manner. Expression of pro-inflammatory enzymes, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) were also inhibited by SBE. These anti-inflammatory effects were due to an inhibitory action of SBE on LPS-induced iNOS, COX-2, TNF-α, IL-1β, and IL-12 mRNA expressions. Moreover, SBE efficiently suppressed IκB phosphorylation and NF-κB nuclear translocation induced by LPS. These findings explain the molecular bases of shea butter's bioactivity against various inflammatory conditions and substantiate it as a latent source of novel therapeutic agents.

Increased pulmonary vascular contraction to serotonin after cardiopulmonary bypass: role of cyclooxygenase.

PubMed

Sato, K; Li, J; Metais, C; Bianchi, C; Sellke, F

2000-05-15

Pulmonary vascular resistance is frequently elevated after cardiopulmonary bypass (CPB). We examined if altered pulmonary microvascular reactivity to serotonin (5-HT) is due to altered expression of isoforms of nitric oxide synthase (NOS) or cyclooxygenase (COX). Pigs (n = 8) were heparinized and placed on total CPB for 90 min and then perfused off CPB for 90 min. Noninstrumented pigs (n = 6) served as controls for vascular studies. Relaxation responses (% of precontraction) of microvessels (60-150 microm in diameter) were examined in vitro in a pressurized (20 mm Hg) no-flow state with video microscopic imaging. Expression of eNOS, iNOS, and inducible (COX-2) and constitutive (COX-1) cyclooxygenase was examined with Western blotting and reverse transcription polymerase chain reaction. Pulmonary vascular resistance (PVR) increased from 316 +/- 39 mm Hg x s/cm(5) at baseline to 495 +/- 53 at 60 min and 565 +/- 62 at 90 min after termination of CPB. 5-HT elicited a relaxation response (46.8 +/- 11. 8%) in precontracted control microvessels. This response was not affected by the NOS inhibitor N(G)-nitro-l-arginine. After CPB, pulmonary microvessels contracted significantly to 5-HT (-29 +/- 27%, P < 0.05 vs control). This response was partially inhibited (7 +/- 20%, P = 0.06) in the presence of the COX-2 inhibitor NS398, but was unaffected by the thromboxane synthase inhibitor U63557A (-20 +/- 19%). Expression of iNOS or COX-1 was not changed after CPB. Protein and mRNA expressions of COX-2 both increased significantly after CPB, while that of eNOS decreased by approximately 50%. PVR increased after CPB. This was associated with a hypercontractile response of isolated pulmonary microvessels to 5-HT that was in part mediated by the release of prostaglandins (but not thromboxane) and associated with increased expression of COX-2 and with decreased expression of eNOS. Copyright 2000 Academic Press.

Acceleration of atherogenesis by COX-1-dependent prostanoid formation in low density lipoprotein receptor knockout mice.

PubMed

Praticò, D; Tillmann, C; Zhang, Z B; Li, H; FitzGerald, G A

2001-03-13

The cyclooxygenase (COX) product, prostacyclin (PGI(2)), inhibits platelet activation and vascular smooth-muscle cell migration and proliferation. Biochemically selective inhibition of COX-2 reduces PGI(2) biosynthesis substantially in humans. Because deletion of the PGI(2) receptor accelerates atherogenesis in the fat-fed low density lipoprotein receptor knockout mouse, we wished to determine whether selective inhibition of COX-2 would accelerate atherogenesis in this model. To address this hypothesis, we used dosing with nimesulide, which inhibited COX-2 ex vivo, depressed urinary 2,3 dinor 6-keto PGF(1alpha) by approximately 60% but had no effect on thromboxane formation by platelets, which only express COX-1. By contrast, the isoform nonspecific inhibitor, indomethacin, suppressed platelet function and thromboxane formation ex vivo and in vivo, coincident with effects on PGI(2) biosynthesis indistinguishable from nimesulide. Indomethacin reduced the extent of atherosclerosis by 55 +/- 4%, whereas nimesulide failed to increase the rate of atherogenesis. Despite their divergent effects on atherogenesis, both drugs depressed two indices of systemic inflammation, soluble intracellular adhesion molecule-1, and monocyte chemoattractant protein-1 to a similar but incomplete degree. Neither drug altered serum lipids and the marked increase in vascular expression of COX-2 during atherogenesis. Accelerated progression of atherosclerosis is unlikely during chronic intake of specific COX-2 inhibitors. Furthermore, evidence that COX-1-derived prostanoids contribute to atherogenesis suggests that controlled evaluation of the effects of nonsteroidal anti-inflammatory drugs and/or aspirin on plaque progression in humans is timely.

Effects of tumour necrosis factor α upon the metabolism of the endocannabinoid anandamide in prostate cancer cells.

PubMed

Karlsson, Jessica; Gouveia-Figueira, Sandra; Alhouayek, Mireille; Fowler, Christopher J

2017-01-01

Tumour necrosis factor α (TNFα) is involved in the pathogenesis of prostate cancer, a disease where disturbances in the endocannabinoid system are seen. In the present study we have investigated whether treatment of DU145 human prostate cancer cells affects anandamide (AEA) catabolic pathways. Additionally, we have investigated whether cyclooxygenase-2 (COX-2) can regulate the uptake of AEA into cells. Levels of AEA synthetic and catabolic enzymes were determined by qPCR. AEA uptake and hydrolysis in DU145 and RAW264.7 macrophage cells were assayed using AEA labeled in the arachidonic and ethanolamine portions of the molecule, respectively. Levels of AEA, related N-acylethanolamines (NAEs), prostaglandins (PG) and PG-ethanolamines (PG-EA) in DU145 cells and medium were quantitated by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) analysis. TNFα treatment of DU145 cells increased mRNA levels of PTSG2 (gene of COX-2) and decreased the mRNA of the AEA synthetic enzyme N-acyl-phosphatidylethanolamine selective phospholipase D. mRNA levels of the AEA hydrolytic enzymes fatty acid amide hydrolase (FAAH) and N-acylethanolamine-hydrolyzing acid amidase were not changed. AEA uptake in both DU145 and RAW264.7 cells was inhibited by FAAH inhibition, but not by COX-2 inhibition, even in RAW264.7 cells where the expression of this enzyme had greatly been induced by lipopolysaccharide + interferon γ treatment. AEA and related NAEs were detected in DU145 cells, but PGs and PGE2-EA were only detected when the cells had been preincubated with 100 nM AEA. The data demonstrate that in DU145 cells, TNFα treatment changes the relative expression of the enzymes involved in the hydrolytic and oxygenation catabolic pathways for AEA. In RAW264.7 cells, COX-2, in contrast to FAAH, does not regulate the cellular accumulation of AEA. Further studies are necessary to determine the extent to which inflammatory mediators are involved in the abnormal endocannabinoid signalling system in prostate cancer.

Elucidating the role of Cyclooxygenase-2 in the pathogenesis of oral lichen planus - an immunohistochemical study with supportive histochemical analysis.

PubMed

Singh, Pratyush; Grover, Jasleen; Byatnal, Aditi Amit; Guddattu, Vasudeva; Radhakrishnan, Raghu; Solomon, Monica Charlotte

2017-05-01

Oral lichen planus (OLP) is a chronic, inflammatory disorder that affects the oral mucous membrane. During an inflammatory response, several chemokines and cytokines are released by the cells of the immune system. Activation of MMPs, along with mast cell-derived chymase and tryptase, degrades the basement membrane structural proteins, resulting in basement membrane breaks. To investigate the association between the COX-2 expressions, presence of intact or degranulating mast cells within the connective tissue and the extent of basement membrane discontinuity in OLP cases. This study included a total of 50 formalin-fixed paraffin-embedded specimens (FFPE) of histologically confirmed cases of idiopathic oral lichen planus. A retrospective cross-sectional analysis was carried out by immunohistochemistry to study the epithelial expression of COX-2 and by the use of special stains such as toluidine blue and periodic acid-Schiff (PAS) to study the mast cell count and basement membrane changes in the oral mucosal tissue, respectively. There was a significant (P = 0.03) association between the COX-2 expressions and mast cell count. As the intensity of COX-2 expression increased from mild to moderate or severe, the number of mast cell count almost doubled. Interaction between upregulation of COX-2, mast cell and basement membrane sets a vicious cycle which relates to the chronic nature of the disease. Inhibitors of COX-2 may reduce the inflammatory process preceding the immune dysregulation in OLP. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Ahr2-dependence of PCB126 effects on the swim bladder in relation to expression of CYP1 and cox-2 genes in developing zebrafish

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jönsson, Maria E., E-mail: maria.jonsson@ebc.uu.se; Biology Department, Redfield 3-42 MS 32, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543; Kubota, Akira, E-mail: akubota@whoi.edu

2012-12-01

The teleost swim bladder is assumed a homolog of the tetrapod lung. Both swim bladder and lung are developmental targets of persistent aryl hydrocarbon receptor (AHR) agonists; in zebrafish (Danio rerio) the swim bladder fails to inflate with exposure to 3,3′,4,4′,5-pentachlorobiphenyl (PCB126). The mechanism for this effect is unknown, but studies have suggested roles of cytochrome P450 1 (CYP1) and cyclooxygenase 2 (Cox-2) in some Ahr-mediated developmental effects in zebrafish. We determined relationships between swim bladder inflation and CYP1 and Cox-2 mRNA expression in PCB126-exposed zebrafish embryos. We also examined effects on β-catenin dependent transcription, histological effects, and Ahr2 dependencemore » of the effect of PCB126 on swim bladder using morpholinos targeting ahr2. One-day-old embryos were exposed to waterborne PCB126 or carrier (DMSO) for 24 h and then held in clean water until day 4, a normal time for swim bladder inflation. The effects of PCB126 were concentration-dependent with EC{sub 50} values of 1.4 to 2.0 nM for induction of the CYP1s, 3.7 and 5.1 nM (or higher) for cox-2a and cox-2b induction, and 2.5 nM for inhibition of swim bladder inflation. Histological defects included a compaction of the developing bladder. Ahr2-morpholino treatment rescued the effect of PCB126 (5 nM) on swim bladder inflation and blocked induction of CYP1A, cox-2a, and cox-2b. With 2 nM PCB126 approximately 30% of eleutheroembryos failed to inflate the swim bladder, but there was no difference in CYP1 or cox-2 mRNA expression between those embryos and embryos showing inflated swim bladder. Our results indicate that PCB126 blocks swim bladder inflation via an Ahr2-mediated mechanism. This mechanism seems independent of CYP1 or cox-2 mRNA induction but may involve abnormal development of swim bladder cells. -- Highlights: ► PCB126 caused cellular changes in the developing swim bladder. ► Swim bladder inflation was not related to expression of CYP1 or cox-2. ► Failure of swim bladder inflation is mediated via an Ahr2-dependent mechanism. ► PCB126-exposed zebrafish larvae showed upregulation of the oncogene myca.« less

Naringin attenuates the development of carrageenan-induced acute lung inflammation through inhibition of NF-κb, STAT3 and pro-inflammatory mediators and enhancement of IκBα and anti-inflammatory cytokines.

PubMed

Ahmad, Sheikh Fayaz; Attia, Sabry M; Bakheet, Saleh A; Zoheir, Khairy M A; Ansari, Mushtaq Ahmad; Korashy, Hesham M; Abdel-Hamied, Hala E; Ashour, Abdelkader E; Abd-Allah, Adel R A

2015-04-01

Naringin has been reported to possess diverse pharmacological properties, including anti-arthritic and anti-inflammatory activities. The aim of the present study was to determine the potential anti-inflammatory effect of naringin in a mouse model of carrageenan-induced pleurisy. A single dose of naringin (40 and 80 mg/kg) was administered per oral (p.o.) 1 h before carrageenan (Cg) administration. Pro- and anti-inflammatory cytokines were analysed in pleural fluid. We also assessed the effects of naringin on the expression levels of iNOS, inducible cyclooxygenase isoform (COX-2), ICAM-1, MIP-2, PGE2, STAT3, TGF-β1, nuclear factor kappa B (NF-κB) and inhibitor of kappa B (IκBα) in lung tissue. The histological examinations revealed anti-inflammatory effect of naringin while Cg group deteriorated. Naringin downregulated Th1 and upregulated Th2 cytokines. Western blot analyses revealed increased protein expression of NF-κB, STAT3 and COX-2 and decreased IκBα in response to Cg treatment, which were reversed by the treatment with naringin. In the Cg group, mRNA expression levels of pro-inflammatory mediators upregulated and anti-inflammatory mediators downregulated. Naringin reversed these actions.

Selenoprotein Expression in Macrophages Is Critical for Optimal Clearance of Parasitic Helminth Nippostrongylus brasiliensis*

PubMed Central

Nelson, Shakira M.; Shay, Ashley E.; James, Jamaal L.; Carlson, Bradley A.; Urban, Joseph F.; Prabhu, K. Sandeep

2016-01-01

The plasticity of macrophages is evident in helminthic parasite infections, providing protection from inflammation. Previously we demonstrated that the micronutrient selenium induces a phenotypic switch in macrophage activation from a classically activated (pro-inflammatory; M1/CAM) toward an alternatively activated (anti-inflammatory; M2/AAM) phenotype, where cyclooxygenase (COX)-dependent cyclopentenone prostaglandin J2 (15d-PGJ2) plays a key role. Here, we hypothesize that dietary selenium modulates macrophage polarization toward an AAM phenotype to assist in the increasing clearance of adult Nippostrongylus brasiliensis, a gastrointestinal nematode parasite. Mice on a selenium-adequate (0.08 ppm) diet significantly augmented intestinal AAM presence while decreasing adult worms and fecal egg production when compared with infection of mice on selenium-deficient (<0.01 ppm) diet. Further increase in dietary selenium to supraphysiological levels (0.4 ppm) had very little or no impact on worm expulsion. Normal adult worm clearance and enhanced AAM marker expression were observed in the selenium-supplemented Trspfl/flCreWT mice that express selenoproteins driven by tRNASec (Trsp), whereas N. brasiliensis-infected Trspfl/flCreLysM selenium-supplemented mice showed a decreased clearance, with lowered intestinal expression of several AAM markers. Inhibition of the COX pathway with indomethacin resulted in delayed worm expulsion in selenium-adequate mice. This was rescued with 15d-PGJ2, which partially recapitulated the effect of selenium supplementation on fecal egg output in addition to increasing markers of AAMs in the small intestine. Antagonism of PPARγ blocked the effect of selenium. These results suggest that optimal expression of selenoproteins and selenium-dependent production of COX-derived endogenous prostanoids, such as Δ12-PGJ2 and 15d-PGJ2, may regulate AAM activation to enhance anti-helminthic parasite responses. PMID:26644468

Differential free fatty acid receptor-1 (FFAR1/GPR40) signalling is associated with gene expression or gelatinase granule release in bovine neutrophils.

PubMed

Mena, Sandra J; Manosalva, Carolina; Carretta, Maria D; Teuber, Stefanie; Olmo, Iván; Burgos, Rafael A; Hidalgo, Maria A

2016-08-01

Fatty acids have been recognized as regulators of immune function in addition to their known metabolic role. Long-chain fatty acids bind free fatty acid receptor (FFAR)-1/GPR40, which is expressed on bovine neutrophils, and increase responses such as granule release and gene expression. In this study, we investigated the molecular mechanisms governing the up-regulation of cyclooxygenase-2 (COX-2) and IL-8, as well as matrix metalloproteinase (MMP)-9 granule release in FFAR1/GPR40 agonist-stimulated neutrophils. Our results showed that natural (oleic and linoleic acid) and synthetic (GW9508) FFAR1/GPR40 agonists increased ERK1/2, p38 MAPK and Akt phosphorylation, and that the FFAR1/GPR40 antagonist GW1100 reduced these responses. We evaluated the levels of IκBα, a component of the classical activation pathway of the transcription factor NF-κB, and we observed IκBα reduction after stimulation with FFAR1/GPR40 agonists, an effect that was inhibited by GW1100 or the inhibitors UO126, SB203580 or LY294002. FFAR1/GPR40 agonists increased COX-2 and IL-8 expression, which was inhibited by GW1100 and an NF-κB inhibitor. Finally, the FFAR1/GPR40 agonist-induced MMP-9 granule release was reduced by GW1100 and UO126. In conclusion, FFAR1/GPR40 agonists differentially stimulate neutrophil functions; COX-2 and IL-8 are expressed after FFAR1/GPR40 activation via NF-κB, IκBα reduction is FFAR1/GPR40- and PI3K/MAPK-dependent, and MMP-9 granule release is FFAR1/GPR40- and ERK1/2-dependent. © The Author(s) 2016.

Dendritic cells issued in vitro from bone marrow produce PGE(2) that contributes to the immunomodulation induced by antigen-presenting cells.

PubMed

Harizi, H; Juzan, M; Grosset, C; Rashedi, M; Gualde, N

2001-04-10

Given that preliminary work has indicated that prostaglandins can play a role in modulating dendritic cell (DC) functions, we addressed the prostaglandin E(2) (PGE(2)) biosynthetic capacity of mouse DC produced in vitro from bone marrow cells. We observed production of significant amounts of PGE(2), which was reduced by at least 80% when cells were incubated in the presence of indomethacin, a COX-1 preferential inhibitor. Indeed, when tested by Western blot analysis with specific COX-1 and COX-2 antibodies, only COX-1 expression could be detected in the bone marrow (BM)-DC. For lipopolysaccharide (LPS)-treated BM-DC, inhibition of PGE(2) production by indomethacin or by NS-398 (a COX-2-selective inhibitor) used alone was less potent. After LPS treatment of BM-DC, COX-1 and COX-2 expression was potent, and inhibition of PGE(2) synthesis needed the presence of both indomethacin and NS-398. We also observed that exogenous PGE(2) diminished the expression of MHC class II molecules by BM-DC and that prostaglandin and indomethacin had antagonistic effects on cell proliferation during the mixed lymphocyte reaction using BM-DC as stimulatory cells. This assessment of PGE(2) suggests that endogenous PGE(2) produced by DC might play a role as an immunomodulating factor during the immune response. This hypothesis is sustained by the fact that IL-12 production by BM-DC is modulated by exogenous PGE(2) as well as endogenous prostaglandin, since either the addition of exogenous PGE(2) or the presence of LPS (which increases endogenous PGE(2) synthesis) decreases IL-12 production, while NS-398 (which decreases LPS-induced PGE(2) synthesis) increases IL-12 synthesis. Copyright 2001 Academic Press.

Pinocembrin attenuates lipopolysaccharide-induced inflammatory responses in Labeo rohita macrophages via the suppression of the NF-κB signalling pathway.

PubMed

Giri, Sib Sankar; Sen, Shib Sankar; Sukumaran, Venkatachalam; Park, Se Chang

2016-09-01

Pinocembrin is a flavonoid that has been reported to exhibit various pharmacological and biological activities including antimicrobial, antioxidant, and anti-inflammatory. To explore the anti-inflammatory activity of pinocembrin in a fish cell line, we investigated its ability to regulate the inflammatory mediators elevated by lipopolysaccharide (LPS) in Labeo rohita head-kidney (HK) macrophages. HK macrophages of L. rohita were treated with LPS (1 μg mL(-1)) in the presence or absence of pinocembrin. We examined the inhibitory effect of pinocembrin on LPS-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production. The inhibitory effect of pinocembrin on nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) was investigated by RT-PCR and western blot. The effect of pinocembrin on pro-inflammatory cytokines (tumour necrosis factor alpha (TNF-α) and interleukin-1β (IL-1β)) and anti-inflammatory cytokine IL-10 was investigated by ELISA and RT-PCR. The phosphorylation of three mitogen activated protein kinases (MAPKs) ERK, JNK, and p38 was analysed by western blot. Pinocembrin inhibited LPS-induced productions of NO and PGE2, and also markedly inhibited TNF-α, IL-1β, iNOS, and COX-2 production in a concentration-dependent manner. In addition, TNF-α and IL-1β mRNA expression levels decreased significantly, while IL-10 mRNA expression increased (P < 0.05) with pinocembrin pre-treatment. RT-PCR and western blot analysis showed that pinocembrin decreased both the mRNA and protein expression levels of LPS-induced iNOS and COX-2 in HK macrophages. Pinocembrin suppressed the phosphorylation of MAPK in LPS-stimulated HK macrophages. Further, pinocembrin significantly inhibited LPS-induced NF-κB transcriptional activity via the attenuation of IκBα degradation. Taken together, pinocembrin reduced the levels of pro-inflammatory mediators, such as iNOS, COX-2, TNF-α, and IL-1β, by inhibiting NF-κB activation via the suppression of ERK and p38 phosphorylation, and by attenuating the degradation of IκBα. These results suggest that pinocembrin is a potential novel candidate for the treatment of inflammatory conditions in L. rohita macrophages. Copyright © 2016 Elsevier Ltd. All rights reserved.

EPA or DHA enhanced oxidative stress and aging protein expression in brain of d-galactose treated mice.

PubMed

Hsu, Yuan-Man; Yin, Mei-Chin

2016-06-01

Effects of eicosapentaenoic acid (EPA, 20:5) and docosahexaenoic acid (DHA, 22:6) upon fatty acid composition, oxidative and inflammatory factors and aging proteins in brain of d-galactose (DG) treated aging mice were examined. Each fatty acid at 7 mg/kg BW/week was supplied for 8 weeks. Brain aging was induced by DG treatment (100 mg/kg body weight) via daily subcutaneous injection for 8 weeks. DG, EPA and DHA treatments changed brain fatty acid composition. DG down-regulated brain Bcl-2 expression and up-regulated Bax expression. Compared with DG groups, EPA and DHA further enhanced Bax expression. DG decreased glutathione content, increased reactive oxygen species (ROS) and oxidized glutathione (GSSG) production, the intake of EPA or DHA caused greater ROS and GSSG formation. DG treatments up-regulated the protein expression of p47(phox) and gp91(phox), and the intake of EPA or DHA led to greater p47(phox) and gp91(phox) expression. DG increased brain prostaglandin E2 (PGE2) levels, and cyclooxygenase (COX)-2 expression and activity, the intake of EPA or DHA reduced brain COX-2 activity and PGE2 formation. DG enhanced brain p53, p16 and p21 expression. EPA and DHA intake led to greater p21 expression, and EPA only caused greater p53 and p16 expression. These findings suggest that these two PUFAs have toxic effects toward aging brain.

Lentiviral infection of rhesus macaques causes long-term injury to cortical and hippocampal projections of prostaglandin-expressing cholinergic basal forebrain neurons.

PubMed

Depboylu, Candan; Weihe, Eberhard; Eiden, Lee E

2012-01-01

The simian immunodeficiency virus (SIV) macaque model resembles human immunodeficiency virus-acquired immunodeficiency syndrome (AIDS) and associated brain dysfunction. Altered expression of synaptic markers and transmitters in neuro-AIDS has been reported, but limited data exist for the cholinergic system and lipid mediators such as prostaglandins. Here, we analyzed cholinergic basal forebrain neurons with their telencephalic projections and the rate-limiting enzymes for prostaglandin synthesis, cyclooxygenase isotypes 1 and 2 (COX1 and COX2) in the brains of SIV-infected macaques with or without encephalitis and antiretroviral therapy and uninfected controls.Cyclooxygenase isotype 1, but not COX2, was coexpressed with markers of cholinergic phenotype, that is, choline acetyltransferase and vesicular acetylcholine transporter (VAChT), in basal forebrain neurons of monkey, as well as human, brain. Cyclooxygenase isotype 1 was decreased in basal forebrain neurons in macaques with AIDS versus uninfected and asymptomatic SIV-infected macaques. The VAChT-positive fiber density was reduced in frontal, parietal, and hippocampal-entorhinal cortex. Although brain SIV burden and associated COX1- and COX2-positive mononuclear and endothelial inflammatory reactions were mostly reversed in AIDS-diseased macaques that received 6-chloro-2',3'-dideoxyguanosine treatment, decreased VAChT-positive terminal density and reduced cholinergic COX1 expression were not. Thus, COX1 expression is a feature of primate cholinergic basal forebrain neurons; it may be functionally important and a critical biomarker of cholinergic dysregulation accompanying lentiviral encephalopathy. These results further imply that insufficiently prompt initiation of antiretroviral therapy in lentiviral infection may lead to neurostructurally unremarkable but neurochemically prominent irreversible brain damage.

Losartan reverses COX-2-dependent vascular dysfunction in offspring of hyperglycaemic rats.

PubMed

de Queiroz, Diego Barbosa; Ramos-Alves, Fernanda Elizabethe; Santos-Rocha, Juliana; Duarte, Gloria Pinto; Xavier, Fabiano Elias

2017-09-01

This study examined whether chronic treatment with losartan, an angiotensin II type 1 receptor (AT 1 R) antagonist, might reverse COX-2-mediated vascular dysfunction in mesenteric resistance arteries (MRA) from offspring of hyperglycaemic rats. Male 12-month-old offspring of hyperglycaemic (O-DR) and normoglycaemic (O-CR) rats were treated with losartan (15mg·kg·day -1 ) during 2months. Third order MRA of untreated and losartan-treated O-DR and O-CR were mounted in wire myograph for isometric tension measurements. COX-2 expression was analyzed by Western blot; TxA 2 , PGE 2 and PGF 2α release was measured using commercial kits. O-DR showed increased blood pressure, impaired acetylcholine-induced vasodilation and increased noradrenaline-induced vasoconstriction than O-CR. All these parameters were normalized by losartan in O-DR. Pre-incubation of MRA with indomethacin (COX-1/2 inhibitor), NS-398 (COX-2 inhibitor) or tempol (superoxide dismutase mimetic) increased relaxation to acetylcholine and reduced contraction to noradrenaline only in O-DR. COX-2 expression, TxA 2 , PGE 2 and PGF 2α release were increased in O-DR. In losartan-treated O-DR, NS-398, indomethacin or tempol failed to produce any effect on acetylcholine or noradrenaline responses. Losartan treatment reduced COX-2 expression, TxA 2 , PGE 2 and PGF 2α release in O-DR. The present results reveal that chronic losartan administration in O-DR normalizes endothelial function in MRA by correcting the existing COX-2 overexpression and the imbalance between endothelium-derived relaxing and contracting factors. These findings not only support the beneficial effects of AT 1 receptor antagonist in O-DR, but also suggest the implication of angiotensin II as a putative mediator of hyperglycemia-programmed vascular dysfunction in rats. Copyright © 2017 Elsevier Inc. All rights reserved.

Parathyroid hormone modulates the response of osteoblast-like cells to mechanical stimulation

NASA Technical Reports Server (NTRS)

Ryder, K. D.; Duncan, R. L.

2000-01-01

Mechanical loading stimulates many responses in bone and osteoblasts associated with osteogenesis. Since loading and parathyroid hormone (PTH) activate similar signaling pathways in osteoblasts, we postulate that PTH can potentiate the effects of mechanical stimulation. Using an in vitro four-point bending device, we found that expression of COX-2, the inducible isoform of cyclooxygenase, was dependent on fluid forces generated across the culture plate, but not physiologic levels of strain in MC3T3-E1 osteoblast-like cells. Addition of 50 nM PTH during loading increased COX-2 expression at both subthreshold and threshold levels of fluid forces compared with either stimuli alone. We also demonstrated that application of fluid shear to MC3T3-E1 cells induced a rapid increase in [Ca(2+)](i). Although PTH did not significantly change [Ca(2+)](i) levels, flow and PTH did produce a significantly greater [Ca(2+)](i) response and increased the number of responding cells than is found in fluid shear alone. The [Ca(2+)](i) response to these stimuli was significantly decreased when the mechanosensitive channel inhibitor, gadolinium, was present. These studies indicate that PTH increases the cellular responses of osteoblasts to mechanical loading. Furthermore, this response may be mediated by alterations in [Ca(2+)](i) by modulating the mechanosensitive channel.

Chemopreventive effects of NSAIDs as inhibitors of cyclooxygenase-2 and inducers of apoptosis in experimental lung carcinogenesis.

PubMed

Setia, Shruti; Vaish, Vivek; Sanyal, Sankar Nath

2012-07-01

Roles of cyclooxygenase (COX) enzyme and intrinsic pathway of apoptosis have been explored for the chemopreventive effects of non-steroidal anti-inflammatory drugs (NSAIDs) on 9,10-dimethyl benz(a)anthracene (DMBA)-induced lung cancer in rat model. 16 weeks after the administration of DMBA, morphological analysis revealed the occurrences of tumours and lesions, which were regressed considerably with the co-administration of indomethacin and etoricoxib, the two NSAIDs under investigation. DMBA group was marked by hyperplasia and dysplasia as observed by histological examination, and these features were corrected to a large extent by the two NSAIDs. Elevated levels of COX-2 were seen in the DMBA group, the enzyme responsible for prostaglandin synthesis during inflammation and cancer, whilst the expression of the constitutive isoform, COX-1, was equally expressed in all the groups. Apoptosis was quantified by studying the activities of apaf-1, caspase-9, and 3 by immunofluorescence and western blots. Their activities were found to diminish in the DMBA-treated animals as compared to the other groups. Fluorescent co-staining of the isolated broncho-alveolar lavage cells showed reduced number of apoptotic cells in the DMBA group, indicating decrease in apoptosis after carcinogen administration. The present results thus suggest that the mechanism of cancer chemoprevention of NSAIDs may include the suppression of COX-2 and the induction of apoptosis.

Cyclooxygenase-2 inhibitors for non-small-cell lung cancer: A phase II trial and literature review.

PubMed

Yokouchi, Hiroshi; Kanazawa, Kenya; Ishida, Takashi; Oizumi, Satoshi; Shinagawa, Naofumi; Sukoh, Noriaki; Harada, Masao; Ogura, Shigeaki; Munakata, Mitsuru; Dosaka-Akita, Hirotoshi; Isobe, Hiroshi; Nishimura, Masaharu

2014-09-01

Several preclinical and clinical studies have demonstrated that cyclooxygenase-2 (COX-2) inhibitors are efficient for the treatment of non-small-cell lung cancer (NSCLC). However, two recent phase III clinical trials using COX-2 inhibitors in combination with platinum-based chemotherapy failed to demonstrate a survival benefit. Thus, validation and discussion regarding the usefulness of COX-2 inhibitors for patients with NSCLC are required. We conducted a prospective trial using COX-2 inhibitors for the treatment of 50 NSCLC patients accrued between April, 2005 and July, 2006. Patients with untreated advanced NSCLC received oral meloxicam (150 mg daily), carboplatin (area under the curve = 5 mg/ml × min on day 1) and docetaxel (60 mg/m 2 on day 1) every 3 weeks. The primary endpoint was response rate. The response and disease control rates were 36.0 and 76.0%, respectively. The time-to-progression (TTP) and overall survival (OS) were 5.7 months [95% confidence interval (CI): 4.6-6.7] and 13.7 months (95% CI: 11.4-15.9), respectively. The 1-year survival ratio was 56.0%. Grade 3 neuropathy was observed in only 1 patient. We performed tumor immunohistochemistry for COX-2 and p27 and investigated the correlation between their expression and clinical outcome. COX-2 expression in the tumor tended to correlate with a higher response rate (50.0% in the high- and 18.2% in the low-COX-2 group; P=0.092). Based on our results and previous reports, various trial designs, such as the prospective use of COX-2 inhibitors only for patients with COX-2-positive NSCLC, including the exploratory analysis of biomarkers associated with the COX-2 pathway, may be worth further consideration.

Treatment with LPS plus INF-γ induces the expression and function of muscarinic acetylcholine receptors, modulating NIH3T3 cell proliferation: participation of NOS and COX.

PubMed

Español, A J; Maddaleno, M O; Lombardi, M G; Cella, M; Martínez Pulido, P; Sales, M E

2014-11-01

LPS and IFN-γ are potent stimuli of inflammation, a process in which fibroblasts are frequently involved. We analysed the effect of treatment with LPS plus IFN-γ on the expression and function of muscarinic acetylcholine receptors in NIH3T3 fibroblasts with regards to proliferation of these cells. We also investigated the participation of NOS and COX, and the role of NF-κB in this process. NIH3T3 cells were treated with LPS (10 ng·mL(-1)) plus IFN-γ (0.5 ng·mL(-1)) for 72 h (iNIH3T3 cells). Cell proliferation was evaluated with MTT and protein expression by Western blot analysis. NOS and COX activities were measured by the Griess method and radioimmunoassay respectively. The cholinoceptor agonist carbachol was more effective at stimulating proliferation in iNIH3T3 than in NIH3T3 cells, probably due to the de novo induction of M3 and M5 muscarinic receptors independently of NF-κB activation. iNIH3T3 cells produced higher amounts of NO and PGE2 than NIH3T3 cells, concomitantly with an up-regulation of NOS1 and COX-2, and with the de novo induction of NOS2/3 in inflamed cells. We also found a positive feedback between NOS and COX that could potentiate inflammation. Inflammation induced the expression of muscarinic receptors and, therefore,stimulated carbachol-induced proliferation of fibroblasts. Inflammation also up-regulated the expression of NOS and COX-2, thus potentiating the effect of carbachol on NO and PGE2 production. A positive crosstalk between NOS and COX triggered by carbachol in inflamed cells points to muscarinic receptors as potential therapeutic targets in inflammation. © 2014 The British Pharmacological Society.

Treatment with LPS plus INF-γ induces the expression and function of muscarinic acetylcholine receptors, modulating NIH3T3 cell proliferation: participation of NOS and COX

PubMed Central

Español, A J; Maddaleno, M O; Lombardi, M G; Cella, M; Martínez Pulido, P; Sales, M E

2014-01-01

Background and Purpose LPS and IFN-γ are potent stimuli of inflammation, a process in which fibroblasts are frequently involved. We analysed the effect of treatment with LPS plus IFN-γ on the expression and function of muscarinic acetylcholine receptors in NIH3T3 fibroblasts with regards to proliferation of these cells. We also investigated the participation of NOS and COX, and the role of NF-κB in this process. Experimental Approach NIH3T3 cells were treated with LPS (10 ng·mL−1) plus IFN-γ (0.5 ng·mL−1) for 72 h (iNIH3T3 cells). Cell proliferation was evaluated with MTT and protein expression by Western blot analysis. NOS and COX activities were measured by the Griess method and radioimmunoassay respectively. Key Results The cholinoceptor agonist carbachol was more effective at stimulating proliferation in iNIH3T3 than in NIH3T3 cells, probably due to the de novo induction of M3 and M5 muscarinic receptors independently of NF-κB activation. iNIH3T3 cells produced higher amounts of NO and PGE2 than NIH3T3 cells, concomitantly with an up-regulation of NOS1 and COX-2, and with the de novo induction of NOS2/3 in inflamed cells. We also found a positive feedback between NOS and COX that could potentiate inflammation. Conclusions and Implications Inflammation induced the expression of muscarinic receptors and, therefore,stimulated carbachol-induced proliferation of fibroblasts. Inflammation also up-regulated the expression of NOS and COX-2, thus potentiating the effect of carbachol on NO and PGE2 production. A positive crosstalk between NOS and COX triggered by carbachol in inflamed cells points to muscarinic receptors as potential therapeutic targets in inflammation. PMID:24990429

Berberine improves endothelial function by inhibiting endoplasmic reticulum stress in the carotid arteries of spontaneously hypertensive rats.

PubMed

Liu, Limei; Liu, Jian; Huang, Zhengxiang; Yu, Xiaoxing; Zhang, Xinyu; Dou, Dou; Huang, Yu

2015-03-20

Activation of endoplasmic reticulum (ER) stress in endothelial cells leads to increased oxidative stress and often results in cell death, which has been implicated in hypertension. The present study investigated the effects of berberine, a botanical alkaloid purified from Coptidis rhizoma, on ER stress in spontaneously hypertensive rats (SHRs) and the underling mechanism. Isolated carotid arteries from normotensive WKYs and SHRs were suspended in myograph for isometric force measurement. Protein phosphorylations and expressions were determined by Western blotting. Reactive oxygen species (ROS) level was measured by DHE staining. SHR carotid arteries exhibited exaggerated acetylcholine-triggered endothelium-dependent contractions (EDCs) and elevated ROS accumulation compared with WKY arteries. Moreover, Western blot analysis revealed the reduced AMPK phosphorylation, increased eIF2α phosphorylation, and elevated levels of ATF3, ATF6, XBP1 and COX-2 in SHR carotid arteries while these pathological alterations were reversed by 12 h-incubation with berberine. Furthermore, AMPK inhibitor compound C or dominant negative AMPK adenovirus inhibited the effects of berberine on above-mentioned marker proteins and EDCs. More importantly, ROS scavengers, tempol and tiron plus DETCA, or ER stress inhibitors, 4-PBA and TUCDA normalized the elevated levels of ROS and COX-2 expression, and attenuated EDCs in SHR arteries. Taken together, the present results suggest that berberine reduces EDCs likely through activating AMPK, thus inhibiting ER stress and subsequently scavenging ROS leading to COX-2 down-regulation in SHR carotid arteries. The present study thus provides additional insights into the vascular beneficial effects of berberine in hypertension. Copyright © 2015 Elsevier Inc. All rights reserved.

Anti-inflammatory intestinal activity of Arctium lappa L. (Asteraceae) in TNBS colitis model.

PubMed

de Almeida, Ana Beatriz Albino; Sánchez-Hidalgo, Marina; Martín, Antonio Ramón; Luiz-Ferreira, Anderson; Trigo, José Roberto; Vilegas, Wagner; dos Santos, Lourdes Campaner; Souza-Brito, Alba Regina Monteiro; de la Lastra, Catalina Alarcón

2013-03-07

In Brazilian traditional medicine, Arctium lappa (Asteraceae), has been reported to relieve gastrointestinal symptoms. In the present study, we investigated the effects of the lactone sesquiterpene onopordopicrin enriched fraction (ONP fraction) from Arctium lappa in an experimental colitis model induced by 2,4,6 trinitrobenzene sulfonic acid and performed experiments to elucidate the underlying action mechanisms involved in that effect. ONP fraction (25 and 50 mg/kg/day) was orally administered 48, 24 and 1 h prior to the induction of colitis and 24 h after. The inflammatory response was assessed by gross appearance, myeloperoxidase (MPO) activity, tumor necrosis factor alpha (TNF-α) levels and a histological study of the lesions. We determined cyclooxygenase (COX)-1 and -2 protein expressions by western blotting and immunohistochemistry assays. TNBS group was characterized by increased colonic wall thickness, edema, diffuse inflammatory cell infiltration, increased MPO activity and TNF-α levels. On the contrary, ONP fraction (25 and 50 mg/kg) treatment significantly reduced the macroscopic inflammation scores (p<0.05 and p<0.01, respectively) and morphological alterations associated with an increase in the mucus secretion. Similarly, the degree of neutrophil infiltration and the cytokine levels were significantly ameliorated. Moreover, COX-2 expression was up regulated in TNBS-treated rats. In contrast, ONP fraction (50 mg/kg) administration reduced COX-2 overexpression. We have shown that the ONP fraction obtained from Arctium lappa exert marked protective effects in acute experimental colitis, confirming and justifying, at least in part, the popular use of this plant to treat gastrointestinal diseases. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Measurements of canine aqueous humor inflammatory mediators and the effect of carprofen following anterior chamber paracentesis.

PubMed

Pinard, Chantale L; Gauvin, Dominique; Moreau, Maxim; Martel-Pelletier, Johanne; Pelletier, Jean-Pierre; Troncy, Eric

2011-09-01

Phase I: To evaluate levels of prostaglandin E(2) (PGE(2) ), nitrites and nitrates (NO(x) ), tumor necrosis factor-alpha (TNF-α) and expression of inducible cyclo-oxygenase (COX-2), nitric oxide synthase (NOS-2), and matrix metalloproteinases (MMP-3 and -9) in canine aqueous humor following repeated anterior chamber paracenteses (ACP). Phase II: to evaluate the effect of carprofen on PGE(2) , NO(x) , and TNF-α in canine aqueous humor following ACP. Four beagles in phase I and 8 beagles in phase II. Phase I: ACP was performed at time (T) 0, 4 and 8 h. Phase II: A randomized, placebo-controlled cross-over design with four dogs per group where carprofen was given 4.4 mg/kg/day on day (D) 1, 2 and 3. ACP was performed at T0 and T1.5 on D3. Statistical analysis was performed with repeated measures anova and post hoc Tukey-Kramer multiple-comparison procedure. In phase II, TNF-α level was analyzed with a Wilcoxon signed-rank test. Phase I: PGE(2) significantly increased (P < 0.0001) to plateau at T4. NO(X) was decreased at T4 (P < 0.06), but increased at T8 (P < 0.0001). COX-2 showed detectable expression only at T8. TNF-α, NOS-2, MMP-3 and -9 were undetectable at all time points. Phase II: At T1.5, PGE(2) was significantly elevated in both groups but was lower in the carprofen group (P = 0.037). NO(x) and TNF-α did not statistically increase in either group. Following ACP, significant increases in PGE(2) levels confirmed inflammation characterized by a rise of COX-2. The NO(x) pathway took longer to induce as compared with PGE(2) . Carprofen decreased PGE(2) levels and could help control intraocular inflammation. © 2011 American College of Veterinary Ophthalmologists.

[Effect of nonsteroidal antiinflammatory drugs on colonic lipoxygenase and cyclooxygenase activities from patients with colonic neoplasia].

PubMed

Di Girolamo, G; Franchi, A; De Los Santos, A R; Martí, M L; Farina, M; Fernández de Gimeno, M A

2001-01-01

Lysine clonixinate (LC) is a nonsteroidal anti-inflammatory drug (NSAID) with good gastrointestinal tolerance. Treatment with LC at levels equivalent to those found in plasma following therapeutic doses resulted in significant inhibition of both cyclooxygenase 2 (COX-2) and production of 5 hydroxy-eicosatetraeonic acid (5-HETE) and slightly affected levels of cyclooxygenase 1 (COX-1) in in vitro studies carried out on human tissues. This study deals with the in vivo effect of the drug on human colon segments. Experiment 1: Five patients about to undergo hemicholectomy due to colon neoplasia were treated preoperatively with a continuous infusion of LC, to achieve a steady-state concentration between 4 and 6 mg/ml. Human colon segments from the five patients and from another five control patients receiving no treatment with [14C]-arachidonic acid were incubated. Human colon segments treated with LC showed significant inhibition of PGE2, the only prostaglandin (PG) synthesised by the tissue, as well as of 5-HETE. Experiment 2: Fifteen patients received an i.v. bolus of LC 100 mg (n1 = 5); LC 200 mg (n2 = 5) or indomethacin (INDO) 50 mg (n3 = 5). Both doses of LC showed greater inhibition of PGE2 synthesis than the INDO bolus. Both NSAIDs studied proved to have different effects on the production of 5-HETE; while treatment with LC elicited significant inhibition, levels with INDO remained unchanged. Western blotting analysis showed expression of both COX isoforms in colon segments, COX-2 levels being 20% higher. Both types of in vivo studies conducted continuous infusion and i.v. bolus, revealed that LC exerted significant inhibition of basal synthesis of PGE2 and 5-HETE.

Abalone visceral extract inhibit tumor growth and metastasis by modulating Cox-2 levels and CD8+ T cell activity.

PubMed

Lee, Choong-Gu; Kwon, Ho-Keun; Ryu, Jae Ha; Kang, Sung Jin; Im, Chang-Rok; Ii Kim, Jae; Im, Sin-Hyeog

2010-10-20

Abalone has long been used as a valuable food source in East Asian countries. Although the nutritional importance of abalone has been reported through in vitro and in vivo studies, there is little evidence about the potential anti-tumor effects of abalone visceral extract. The aim of the present study is to examine anti-tumor efficacy of abalone visceral extract and to elucidate its working mechanism. In the present study, we used breast cancer model using BALB/c mouse-derived 4T1 mammary carcinoma and investigated the effect of abalone visceral extract on tumor development. Inhibitory effect against tumor metastasis was assessed by histopathology of lungs. Cox-2 productions by primary and secondary tumor were measured by real-time RT-PCR and immunoblotting (IB). Proliferation assay based on [3H]-thymidine incorporation and measurement of cytokines and effector molecules by RT-PCR were used to confirm tumor suppression efficacy of abalone visceral extract by modulating cytolytic CD8+ T cells. The cytotoxicity of CD8+ T cell was compared by JAM test. Oral administration of abalone visceral extract reduced tumor growth (tumor volume and weight) and showed reduced metastasis as confirmed by decreased level of splenomegaly (spleen size and weight) and histological analysis of the lung metastasis (gross analysis and histological staining). Reduced expression of Cox-2 (mRNA and protein) from primary tumor and metastasized lung was also detected. In addition, treatment of abalone visceral extract increased anti-tumor activities of CD8+ T cells by increasing the proliferation capacity and their cytolytic activity. Our results suggest that abalone visceral extract has anti-tumor effects by suppressing tumor growth and lung metastasis through decreasing Cox-2 expression level as well as promoting proliferation and cytolytic function of CD8+ T cells.

Abalone visceral extract inhibit tumor growth and metastasis by modulating Cox-2 levels and CD8+ T cell activity

PubMed Central

2010-01-01

Background Abalone has long been used as a valuable food source in East Asian countries. Although the nutritional importance of abalone has been reported through in vitro and in vivo studies, there is little evidence about the potential anti-tumor effects of abalone visceral extract. The aim of the present study is to examine anti-tumor efficacy of abalone visceral extract and to elucidate its working mechanism. Methods In the present study, we used breast cancer model using BALB/c mouse-derived 4T1 mammary carcinoma and investigated the effect of abalone visceral extract on tumor development. Inhibitory effect against tumor metastasis was assessed by histopathology of lungs. Cox-2 productions by primary and secondary tumor were measured by real-time RT-PCR and immunoblotting (IB). Proliferation assay based on [3H]-thymidine incorporation and measurement of cytokines and effector molecules by RT-PCR were used to confirm tumor suppression efficacy of abalone visceral extract by modulating cytolytic CD8+ T cells. The cytotoxicity of CD8+ T cell was compared by JAM test. Results Oral administration of abalone visceral extract reduced tumor growth (tumor volume and weight) and showed reduced metastasis as confirmed by decreased level of splenomegaly (spleen size and weight) and histological analysis of the lung metastasis (gross analysis and histological staining). Reduced expression of Cox-2 (mRNA and protein) from primary tumor and metastasized lung was also detected. In addition, treatment of abalone visceral extract increased anti-tumor activities of CD8+ T cells by increasing the proliferation capacity and their cytolytic activity. Conclusions Our results suggest that abalone visceral extract has anti-tumor effects by suppressing tumor growth and lung metastasis through decreasing Cox-2 expression level as well as promoting proliferation and cytolytic function of CD8+ T cells. PMID:20961430

Azoxymethane protects intestinal stem cells and reduces crypt epithelial mitosis through a COX-1-dependent mechanism.

PubMed

Riehl, Terrence E; George, Robert J; Sturmoski, Mark A; May, Randal; Dieckgraefe, Brian; Anant, Shrikant; Houchen, Courtney W

2006-12-01

Azoxymethane (AOM) is a potent DNA-damaging agent and carcinogen that induces intestinal and colonic tumors in rodents. Evaluation of the stem cell population by colony formation assay reveals that, within 8 h after treatment, AOM (10 mg/kg) elicited a prosurvival response. In wild-type (WT) mice, AOM treatment induced a 2.5-fold increase in intestinal crypt stem cell survival. AOM treatment increased stem cell survival in cyclooxygenase (COX)-2(-/-) but not COX-1(-/-) mice, confirming a role of COX-1 in the AOM-induced increase in stem cell survival. COX-1 mRNA and protein expression as well as COX-1-derived PGE(2) synthesis were increased 8 h after AOM treatment. Immunohistochemical staining of COX-1 demonstrated expression of the enzyme in the crypt epithelial cells, especially in the columnar epithelial cells between the Paneth cells adjacent to the stem cell zone. WT mice receiving AOM exhibited increased intestinal apoptosis and a simultaneous reduction in crypt mitotic figures within 8 h of injection. There were no significant differences in baseline or AOM-induced intestinal epithelial apoptosis between WT and COX-1(-/-) mice, but there was a complete reversal of the AOM-mediated reduction in mitosis in COX-1(-/-) mice. This suggests that COX-1-derived PGE(2) may play a key role in the early phase of intestinal tumorigenesis in response to DNA damage and suggests that COX-1 may be a potential therapeutic target in this model of colon cancer.

Effusanin E suppresses nasopharyngeal carcinoma cell growth by inhibiting NF-κB and COX-2 signaling.

PubMed

Zhuang, Mingzhu; Zhao, Mouming; Qiu, Huijuan; Shi, Dingbo; Wang, Jingshu; Tian, Yun; Lin, Lianzhu; Deng, Wuguo

2014-01-01

Rabdosia serra is well known for its antibacterial, anti-inflammatory and antitumor activities, but no information has been available for the active compounds derived from this plant in inhibiting human nasopharyngeal carcinoma (NPC) cell growth. In this study, we isolated and purified a natural diterpenoid from Rabdosia serra and identified its chemical structure as effusanin E and elucidated its underlying mechanism of action in inhibiting NPC cell growth. Effusanin E significantly inhibited cell proliferation and induced apoptosis in NPC cells. Effusanin E also induced the cleavage of PARP, caspase-3 and -9 proteins and inhibited the nuclear translocation of p65 NF-κB proteins. Moreover, effusanin E abrogated the binding of NF-κB to the COX-2 promoter, thereby inhibiting the expression and promoter activity of COX-2. Pretreatment with a COX-2 or NF-κB-selective inhibitor (celecoxib or ammonium pyrrolidinedithiocarbamate) had an additive effect on the effusanin E-mediated inhibition of proliferation, while pretreatment with an activator of NF-κB/COX-2 (lipopolysaccharides) abrogated the effusanin E-mediated inhibition of proliferation. Effusanin E also significantly suppressed tumor growth in a xenograft mouse model without obvious toxicity, furthermore, the expression of p50 NF-κB and COX-2 were down-regulated in the tumors of nude mice. These data suggest that effusanin E suppresses p50/p65 proteins to down-regulate COX-2 expression, thereby inhibiting NPC cell growth. Our findings provide new insights into exploring effusanin E as a potential therapeutic compound for the treatment of human nasopharyngeal carcinoma.

The effect of non-steroidal anti-inflammatory agents on behavioural changes and cytokine production following systemic inflammation: Implications for a role of COX-1

PubMed Central

Teeling, J.L.; Cunningham, C.; Newman, T.A.; Perry, V.H.

2010-01-01

Systemic inflammation gives rise to metabolic and behavioural changes, largely mediated by pro-inflammatory cytokines and prostaglandin production (PGE2) at the blood–brain barrier. Despite numerous studies, the exact biological pathways that give rise to these changes remains elusive. This study investigated the mechanisms underlying immune-to-brain communication following systemic inflammation using various anti-inflammatory agents. Mice were pre-treated with selective cyclo-oxygenase (COX) inhibitors, thromboxane synthase inhibitors or dexamethasone, followed by intra-peritoneal injection of lipopolysaccharide (LPS). Changes in body temperature, open-field activity, and burrowing were assessed and mRNA and/or protein levels of inflammatory mediators measured in serum and brain. LPS-induced systemic inflammation resulted in behavioural changes and increased production of IL-6, IL-1β and TNF-α, as well as PGE2 in serum and brain. Indomethacin and ibuprofen reversed the effect of LPS on behaviour without changing peripheral or central IL-6, IL-1β and TNF-α mRNA levels. In contrast, dexamethasone did not alter LPS-induced behavioural changes, despite complete inhibition of cytokine production. A selective COX-1 inhibitor, piroxicam, but not the selective COX-2 inhibitor, nimesulide, reversed the LPS-induced behavioural changes without affecting IL-6, IL-1β and TNF-α protein expression levels in the periphery or mRNA levels in the hippocampus. Our results suggest that the acute LPS-induced changes in burrowing and open-field activity depend on COX-1. We further show that COX-1 is not responsible for the induction of brain IL-6, IL-1β and TNF-α synthesis or LPS-induced hypothermia. Our results may have implications for novel therapeutic strategies to treat or prevent neurological diseases with an inflammatory component. PMID:19931610

Effect of uric acid on inflammatory COX-2 and ROS pathways in vascular smooth muscle cells.

PubMed

Oğuz, Nurgül; Kırça, Mustafa; Çetin, Arzu; Yeşilkaya, Akın

2017-10-01

Hyperuricemia is thought to play a role in cardiovascular diseases (CVD), including hypertension, coronary artery disease and atherosclerosis. However, exactly how uric acid contributes to these pathologies is unknown. An underlying mechanism of inflammatory diseases, such as atherosclerosis, includes enhanced production of cyclooxygenase-2 (COX-2) and superoxide anion. Here, we aimed to examine the effect of uric acid on inflammatory COX-2 and superoxide anion production and to determine the role of losartan. Primarily cultured vascular smooth muscle cells (VSMCs) were time and dose-dependently induced by uric acid and COX-2 and superoxide anion levels were measured. COX-2 levels were determined by ELISA, and superoxide anion was measured by the superoxide dismutase (SOD)-inhibitable reduction of ferricytochrome c method. Uric acid elevated COX-2 levels in a time-dependent manner. Angiotensin-II receptor blocker, losartan, diminished uric-acid-induced COX-2 elevation. Uric acid also increased superoxide anion level in VSMCs. Uric acid plays an important role in CVD pathogenesis by inducing inflammatory COX-2 and ROS pathways. This is the first study demonstrating losartan's ability to reduce uric-acid-induced COX-2 elevation.

Pleurotus giganteus (Berk. Karun & Hyde), the giant oyster mushroom inhibits NO production in LPS/H2O2 stimulated RAW 264.7 cells via STAT 3 and COX-2 pathways.

PubMed

Baskaran, Asweni; Chua, Kek Heng; Sabaratnam, Vikineswary; Ravishankar Ram, Mani; Kuppusamy, Umah Rani

2017-01-13

Pleurotus giganteus (Berk. Karunarathna and K.D. Hyde), has been used as a culinary mushroom and is known to have medicinal properties but its potential as an anti-inflammatory agent to mitigate inflammation triggered diseases is untapped. In this study, the molecular mechanism underlying the protective effect of ethanol extract of P. giganteus (EPG) against lipopolysaccharide (LPS) and combination of LPS and hydrogen peroxide (H 2 O 2 )-induced inflammation on RAW 264.7 macrophages was investigated. The effect of EPG on nitric oxide (NO) production as an indicator of inflammation in RAW 264.7 macrophages was estimated based on Griess reaction that measures nitrite level. The expressions of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), NF-kB activating protein (NKAP), signal transducer and activator of transcription 3 protein (STAT 3) and glutathione peroxidase (GPx) genes were assessed using real time reverse transcription polymerase chain reaction (RT-PCR) approach. EPG (10 μg/ml) showed the highest reduction in the LPS-induced NO production in RAW 264.7 macrophages and significantly suppressed (p < 0.05) the expression iNOS, STAT 3 and COX-2. There was a significant increase (p < 0.05) in combination of LPS and H 2 O 2 - induced iNOS production when compared to the LPS-induced iNOS production in RAW 264.7 macrophages and this concurred with the NO production which was attenuated by EPG at 10 μg/ml. A significant (p < 0.05) down regulation was observed in the combination of LPS and H 2 O 2 -induced iNOS and GPx expression by EPG. Our data suggest that the anti-inflammatory activity of EPG is mediated via the suppression of the STAT 3 and COX-2 pathways and can serve as potential endogenous antioxidant stimulant.

Ahr2-dependance of PCB126 effects on the swimbladder in relation to expression of CYP1 and cox-2 genes in developing zebrafish

PubMed Central

Jönsson, Maria E.; Kubota, Akira; Timme-Laragy, Alicia; Woodin, Bruce; Stegeman, John J.

2012-01-01

The teleost swimbladder is assumed a homolog of the tetrapod lung. Both swimbladder and lung are developmental targets of persistent aryl hydrocarbon receptor (AHR1) agonists; in zebrafish (Danio rerio) the swimbladder fails to inflate with exposure to 3,3’,4,4’,5-pentachlorobiphenyl (PCB126). The mechanism for this effect is unknown, but studies have suggested roles of cytochrome P4501 (CYP1) and cyclooxygenase 2 (Cox-2) in some Ahr-mediated developmental effects in zebrafish. We determined relationships between swimbladder inflation and CYP1 and Cox-2 mRNA expression in PCB126-exposed zebrafish embryos. We also examined effects on β-catenin dependent transcription, histological effects, and Ahr2 dependance of the effect of PCB126 on swimbladder using morpholinos targeting ahr2. One-day-old embryos were exposed to waterborne PCB126 or carrier (DMSO) for 24 h and then held in clean water until day 4, a normal time for swimbladder inflation. The effects of PCB126 were concentration-dependent with EC50 values of 1.4 to 2.0 nM for induction of the CYP1s, 3.7 and 5.1 nM (or higher) for cox-2a and cox-2b induction, and 2.5 nM for inhibition of swimbladder inflation. Histological defects included a compaction of the developing bladder. Ahr2-morpholino treatment rescued the effect of PCB126 (5 nM) on swimbladder inflation and blocked induction of CYP1A, cox-2a, and cox-2b. With 2 nM PCB126 approximately 30% of eleutheroembryos2 failed to inflate the swimbladder, but there was no difference in CYP1 or cox-2 mRNA expression between those embryos and embryos showing inflated swimbladder. Our results indicate that PCB126 blocks swimbladder inflation via an Ahr2-mediated mechanism. This mechanism seems independent of CYP1 or cox-2 mRNA induction but may involve abnormal development of swimbladder cells. PMID:23036320

Celecoxib restores angiogenic factor expression at the maternal-fetal interface in the BPH/5 mouse model of preeclampsia.

PubMed

Reijnders, Dorien; Liu, Chin-Chi; Xu, Xinjing; Zhao, Anna M; Olson, Kelsey N; Butler, Scott D; Douglas, Nataki C; Sones, Jenny L

2018-05-01

Preeclampsia (PE), a hypertensive disease of pregnancy, is a leading cause of fetal and maternal morbidity/mortality. Early angiogenic and inflammatory disturbances within the placenta are thought to underlie the development of the maternal PE syndrome and poor pregnancy outcomes. However, the exact etiology remains largely unknown. Here, we use the BPH/5 mouse model of PE to elucidate the way in which inflammation early in pregnancy contributes to abnormal expression of angiogenic factors at the maternal-fetal interface. We have previously described improvement in maternal hypertension and fetal growth restriction in this model after treatment with the anti-inflammatory cyclooxygenase-2 (Cox2) specific inhibitor celecoxib. To further characterize the mechanisms by which celecoxib improves poor pregnancy outcomes in BPH/5 mice, we determined expression of angiogenic factors and complement pathway components after celecoxib. In BPH/5 implantation sites there was increased hypoxia inducible factor-1α ( Hif1α), heme oxygenase-1 ( Ho-1), and stem cell factor ( Scf) mRNA concomitant with elevated prostaglandin synthase 2 ( Ptgs2), encoding Cox2, and elevated VEGF protein. Angiopoietin 1 ( Ang1), tunica interna endothelial cell kinase-2 receptor ( Tie2), complement factor 3 ( C3), and complement factor B ( CfB) were increased in midgestation BPH/5 placentae. Whereas BPH/5 expression levels of VEGF, Ang1, and Tie2 normalized after celecoxib, placental C3 and CfB mRNA remained unchanged. However, celecoxib did reduce the pregnancy-specific circulating soluble fms-like tyrosine kinase-1 (sFlt-1) rise in BPH/5 mice at midgestation. These data show that elevated Cox2 during implantation contributes to placental angiogenic factor imbalances in the BPH/5 mouse model of PE.

[Notch1 signaling participates in the release of inflammatory mediators in mouse RAW264.7 cells via activating NF-κB pathway].

PubMed

Zhao, Hongwei; Xu, Che Nan; Huang, Chao; Jiang, Jinzhi; Li, Liangchang

2017-10-01

Objective To study the effect of Notch1 signaling on the release of inflammatory mediators in lipopolysaccharide (LPS)-induced macrophages and the related mechanism. Methods The expressions of Notch1 and hairy and enhancer of split 1 (Hes1) mRNAs were investigated by reverse transcription PCR (RT-PCR) in mouse RAW264.7 cells after stimulated with 100 ng/mL LPS for 8 hours. Prior to stimulation with LPS, mouse RAW264.7 cells were treated with DAPT (10 μmol/L), an inhibitor of Notch1 signaling, for 1 hour. The concentrations of tumor necrosis factor (TNF-α), interleukin 1β (IL-1β), IL-6, nitric oxide (NO) and prostaglandin E 2 (PGE 2 ) in cell culture media were measured by ELISA. The mRNA levels of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were examined by RT-PCR. The protein levels of iNOS, COX-2, nuclear factor kappa Bp65 (NF-κBp65) and phosphorylated nuclear factor κB inhibitor α (p-IκBα) were detected by Western blotting. Results The expressions of Notch1 and Hes1 mRNAs significantly increased in mouse RAW264.7 cells after stimulated with LPS. The levels of TNF-α, IL-1β, IL-6, NO and PGE 2 were significantly up-regulated in cell culture media after stimulated with LPS, but the levels of those inflammatory mediators were reduced by DAPT. The mRNA and protein levels of iNOS and COX-2 were significant raised in mouse RAW264.7 cells after stimulated with LPS, while they were inhibited by DAPT. Both IκBα-phosphorylation and NF-κBp65 translocation into nuclear in LPS-induced RAW264.7 cells were also inhibited by DAPT. Conclusion Notch1 signaling activates NF-κB to participate in LPS-induced inflammatory mediator release in macrophages.

Cancer survival analysis using semi-supervised learning method based on Cox and AFT models with L1/2 regularization.

PubMed

Liang, Yong; Chai, Hua; Liu, Xiao-Ying; Xu, Zong-Ben; Zhang, Hai; Leung, Kwong-Sak

2016-03-01

One of the most important objectives of the clinical cancer research is to diagnose cancer more accurately based on the patients' gene expression profiles. Both Cox proportional hazards model (Cox) and accelerated failure time model (AFT) have been widely adopted to the high risk and low risk classification or survival time prediction for the patients' clinical treatment. Nevertheless, two main dilemmas limit the accuracy of these prediction methods. One is that the small sample size and censored data remain a bottleneck for training robust and accurate Cox classification model. In addition to that, similar phenotype tumours and prognoses are actually completely different diseases at the genotype and molecular level. Thus, the utility of the AFT model for the survival time prediction is limited when such biological differences of the diseases have not been previously identified. To try to overcome these two main dilemmas, we proposed a novel semi-supervised learning method based on the Cox and AFT models to accurately predict the treatment risk and the survival time of the patients. Moreover, we adopted the efficient L1/2 regularization approach in the semi-supervised learning method to select the relevant genes, which are significantly associated with the disease. The results of the simulation experiments show that the semi-supervised learning model can significant improve the predictive performance of Cox and AFT models in survival analysis. The proposed procedures have been successfully applied to four real microarray gene expression and artificial evaluation datasets. The advantages of our proposed semi-supervised learning method include: 1) significantly increase the available training samples from censored data; 2) high capability for identifying the survival risk classes of patient in Cox model; 3) high predictive accuracy for patients' survival time in AFT model; 4) strong capability of the relevant biomarker selection. Consequently, our proposed semi-supervised learning model is one more appropriate tool for survival analysis in clinical cancer research.

Progesterone and the Repression of Myometrial Inflammation: The Roles of MKP-1 and the AP-1 System

PubMed Central

Lei, K.; Georgiou, E. X.; Chen, L.; Yulia, A.; Sooranna, S. R.; Brosens, J. J.; Bennett, P. R.

2015-01-01

Progesterone (P4) maintains uterine quiescence during pregnancy and its functional withdrawal is associated with increased prostaglandin synthesis and the onset of labor. In primary human myometrial cells, the glucocorticoid receptor (GR) rather than the P4 receptor mediates P4 antagonism of IL-1β-induced cyclooxygenase-2 (COX-2) expression, the rate-limiting enzyme in prostaglandin synthesis. We now report that P4 also acts via GR to induce MAPK phosphatase (MKP)-1 and knockdown of MKP-1 impairs the ability of P4 to repress IL-1β-dependent COX-2 induction. Microarray analysis revealed that P4 repressed preferentially activator protein-1-responsive genes in response to IL-1β. Consistent with these observations, we found that the ability of P4 to reduce c-Jun activation was lost upon GR as well as MKP-1 knockdown. Interestingly, c-Jun levels in human myometrial cells declined upon GR and MKP-1 knockdown, which suggests the presence of an activator protein-1 feedback loop. This is supported by our observation that c-Jun levels declined after an initial rise in primary myometrial cells treated with phorbol 12-myrisatate 13-acetate, a potent activator of c-Jun N-terminal kinase. Finally, we show that MKP-1 is an intermediate in P4-mediated repression of some but not all IL-1β-responsive genes. For example, P4 repression of IL11 and IRAK3 was maintained upon MKP-1 knockdown. Taken together, the data show that P4 acts via GR to drive MKP-1 expression, which in turn inhibits IL-1β-dependent c-Jun activation and COX-2 expression. PMID:26280733

Zinc Replenishment Reverses Overexpression of the Proinflammatory Mediator S100A8 and Esophageal Preneoplasia in the Rat

PubMed Central

Taccioli, Cristian; Wan, Shao-Gui; Liu, Chang-Gong; Alder, Hansjuerg; Volinia, Stefano; Farber, John L.; Croce, Carlo M.

2009-01-01

Background & Aims Zinc-deficiency is implicated in the pathogenesis of human esophageal cancer. In the rat esophagus, it induces cell proliferation, modulates genetic expression, and enhances carcinogenesis. Zinc-replenishment reverses proliferation and inhibits carcinogenesis. The zinc-deficient rat model allows the identification of biological differences affected by zinc during early esophageal carcinogenesis. Methods We evaluated gene expression profiles of esophageal epithelia from zinc-deficient and replenished rats versus sufficient rats using Affymetrix Rat Genome GeneChip. We characterized the role of the top-upregulated gene S100A8 in esophageal hyperplasia/reversal and in chemically-induced esophageal carcinogenesis in zinc-modulated animals by immunohistochemistry and real-time quantitative polymerase chain reaction. Results The hyperplastic deficient esophagus has a distinct expression signature with the proinflammation-gene S100A8 and S100A9 upregulated 57- and 5-fold. “Response to external stimulus” comprising S100A8 was the only significantly overrepresented biological pathway among the upregulated genes. Zinc-replenishment rapidly restored to control levels the expression of S100A8/A9 and 27 other genes and reversed the hyperplastic phenotype. With its receptor RAGE, co-localization and overexpression of S100A8 protein occurred in the deficient esophagus that overexpressed NF-κB p65 and COX-2 protein. Zinc-replenishment but not by a COX-2 inhibitor reduced the overexpression of these 4 proteins. Additionally, esophageal S100A8/A9 mRNA levels were directly associated with the diverse tumorigenic outcome in zinc-deficient and zinc-replenished rats. Conclusions In vivo zinc regulates S100A8 expression and modulates the link between S100A8-RAGE interaction and downstream NF-κB/COX-2 signaling. The finding that zinc regulates an inflammatory pathway in esophageal carcinogenesis may lead to prevention and therapy for this cancer. PMID:19111725

Rutin inhibits B[a]PDE-induced cyclooxygenase-2 expression by targeting EGFR kinase activity.

PubMed

Choi, Seunghwan; Lim, Tae-Gyu; Hwang, Mun Kyung; Kim, Yoon-A; Kim, Jiyoung; Kang, Nam Joo; Jang, Tae Su; Park, Jun-Seong; Yeom, Myeong Hun; Lee, Ki Won

2013-11-15

Rutin is a well-known flavonoid that exists in various natural sources. Accumulative studies have represented the biological effects of rutin, such as anti-oxidative and anti-inflammatory effects. However, the underlying mechanisms of rutin and its direct targets are not understood. We investigated whether rutin reduced B[a]PDE-induced-COX-2 expression. The transactivation of AP-1 and NF-κB were inhibited by rutin. Rutin also attenuated B[a]PDE-induced Raf/MEK/ERK and Akt activation, but had no effect on the phosphorylation of EGFR. An in vitro kinase assay revealed rutin suppressed EGFR kinase activity. We also confirmed direct binding between rutin and EGFR, and found that the binding was regressed by ATP. The EGFR inhibitor also inhibited the B[a]PDE-induced MEK/ERK and Akt signaling pathways and subsequently, suppressed COX-2 expression and promoter activity, in addition to suppressing the transactivation of AP-1 and NF-κB. In EGFR(-/-)mouse embryonic fibroblast cells, B[a]PDE-induced COX-2 expression was also diminished. Collectively, rutin inhibits B[a]PDE-induced COX-2 expression by suppressing the Raf/MEK/ERK and Akt signaling pathways. EGFR appeared to be the direct target of rutin. Copyright © 2013 Elsevier Inc. All rights reserved.

Integrated proteomics identified novel activation of dynein IC2-GR-COX-1 signaling in neurofibromatosis type I (NF1) disease model cells.

PubMed

Hirayama, Mio; Kobayashi, Daiki; Mizuguchi, Souhei; Morikawa, Takashi; Nagayama, Megumi; Midorikawa, Uichi; Wilson, Masayo M; Nambu, Akiko N; Yoshizawa, Akiyasu C; Kawano, Shin; Araki, Norie

2013-05-01

Neurofibromatosis type 1 (NF1) tumor suppressor gene product, neurofibromin, functions in part as a Ras-GAP, and though its loss is implicated in the neuronal abnormality of NF1 patients, its precise cellular function remains unclear. To study the molecular mechanism of NF1 pathogenesis, we prepared NF1 gene knockdown (KD) PC12 cells, as a NF1 disease model, and analyzed their molecular (gene and protein) expression profiles with a unique integrated proteomics approach, comprising iTRAQ, 2D-DIGE, and DNA microarrays, using an integrated protein and gene expression analysis chart (iPEACH). In NF1-KD PC12 cells showing abnormal neuronal differentiation after NGF treatment, of 3198 molecules quantitatively identified and listed in iPEACH, 97 molecules continuously up- or down-regulated over time were extracted. Pathway and network analysis further revealed overrepresentation of calcium signaling and transcriptional regulation by glucocorticoid receptor (GR) in the up-regulated protein set, whereas nerve system development was overrepresented in the down-regulated protein set. The novel up-regulated network we discovered, "dynein IC2-GR-COX-1 signaling," was then examined in NF1-KD cells. Validation studies confirmed that NF1 knockdown induces altered splicing and phosphorylation patterns of dynein IC2 isomers, up-regulation and accumulation of nuclear GR, and increased COX-1 expression in NGF-treated cells. Moreover, the neurite retraction phenotype observed in NF1-KD cells was significantly recovered by knockdown of the dynein IC2-C isoform and COX-1. In addition, dynein IC2 siRNA significantly inhibited nuclear translocation and accumulation of GR and up-regulation of COX-1 expression. These results suggest that dynein IC2 up-regulates GR nuclear translocation and accumulation, and subsequently causes increased COX-1 expression, in this NF1 disease model. Our integrated proteomics strategy, which combines multiple approaches, demonstrates that NF1-related neural abnormalities are, in part, caused by up-regulation of dynein IC2-GR-COX-1 signaling, which may be a novel therapeutic target for NF1.

Cyclooxygenase inhibition targets neurons to prevent early behavioural decline in Alzheimer’s disease model mice

PubMed Central

Woodling, Nathaniel S.; Colas, Damien; Wang, Qian; Minhas, Paras; Panchal, Maharshi; Liang, Xibin; Mhatre, Siddhita D.; Brown, Holden; Ko, Novie; Zagol-Ikapitte, Irene; van der Hart, Marieke; Khroyan, Taline V.; Chuluun, Bayarsaikhan; Priyam, Prachi G.; Milne, Ginger L.; Rassoulpour, Arash; Boutaud, Olivier; Manning-Boğ, Amy B.; Heller, H. Craig

2016-01-01

Abstract Identifying preventive targets for Alzheimer’s disease is a central challenge of modern medicine. Non-steroidal anti-inflammatory drugs, which inhibit the cyclooxygenase enzymes COX-1 and COX-2, reduce the risk of developing Alzheimer’s disease in normal ageing populations. This preventive effect coincides with an extended preclinical phase that spans years to decades before onset of cognitive decline. In the brain, COX-2 is induced in neurons in response to excitatory synaptic activity and in glial cells in response to inflammation. To identify mechanisms underlying prevention of cognitive decline by anti-inflammatory drugs, we first identified an early object memory deficit in APP Swe -PS1 ΔE9 mice that preceded previously identified spatial memory deficits in this model. We modelled prevention of this memory deficit with ibuprofen, and found that ibuprofen prevented memory impairment without producing any measurable changes in amyloid-β accumulation or glial inflammation. Instead, ibuprofen modulated hippocampal gene expression in pathways involved in neuronal plasticity and increased levels of norepinephrine and dopamine. The gene most highly downregulated by ibuprofen was neuronal tryptophan 2,3-dioxygenase ( Tdo2 ), which encodes an enzyme that metabolizes tryptophan to kynurenine. TDO2 expression was increased by neuronal COX-2 activity, and overexpression of hippocampal TDO2 produced behavioural deficits. Moreover, pharmacological TDO2 inhibition prevented behavioural deficits in APP Swe -PS1 ΔE9 mice. Taken together, these data demonstrate broad effects of cyclooxygenase inhibition on multiple neuronal pathways that counteract the neurotoxic effects of early accumulating amyloid-β oligomers. PMID:27190010

Microsomal PGE2 synthase-1 regulates melanoma cell survival and associates with melanoma disease progression.

PubMed

Kim, Sun-Hee; Hashimoto, Yuuri; Cho, Sung-Nam; Roszik, Jason; Milton, Denái R; Dal, Fulya; Kim, Sangwon F; Menter, David G; Yang, Peiying; Ekmekcioglu, Suhendan; Grimm, Elizabeth A

2016-05-01

COX-2 and its product PGE2 enhance carcinogenesis and tumor progression, which has been previously reported in melanoma. As most COX inhibitors cause much toxicity, the downstream microsomal PGE2 synthase-1 (mPGES1) is a consideration for targeting. Human melanoma TMAs were employed for testing mPGES1 protein staining intensity and percentage levels, and both increased with clinical stage; employing a different Stage III TMA, mPGES1 intensity (not percentage) associated with reduced patient survival. Our results further show that iNOS was also highly expressed in melanoma tissues with high mPGES1 levels, and iNOS-mediated NO promoted mPGES1 expression and PGE2 production. An mPGES1-specific inhibitor (CAY10526) as well as siRNA attenuated cell survival and increased apoptosis. CAY10526 significantly suppressed tumor growth and increased apoptosis in melanoma xenografts. Our findings support the value of a prognostic and predictive role for mPGES1, and suggest targeting this molecule in the PGE2 pathway as another avenue toward improving melanoma therapy. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Evidence for a Pro-Proliferative Feedback Loop in Prostate Cancer: The Role of Epac1 and COX-2-Dependent Pathways

PubMed Central

Misra, Uma Kant; Pizzo, Salvatore Vincent

2013-01-01

Objective In human prostate cancer cells, a selective Epac agonist, 8-CPT-2Me-cAMP, upregulates cell proliferation and survival via activation of Ras-MAPK and PI- 3-kinase-Akt-mTOR signaling cascades. Here we examine the role of inflammatory mediators in Epac1-induced cellular proliferation by determining the expression of the pro-inflammatory markers p-cPLA2, COX-2, and PGE2 in prostate cancer cells treated with 8-CPT-2Me-cAMP. Methods We employed inhibitors of COX-2, mTORC1, and mTORC2 to probe cyclic AMP-dependent pathways in human prostate cancer cells. RNAi targeting Epac1, Raptor, and Rictor was also employed in these studies. Results 8-CPT-2Me-cAMP treatment caused a 2–2.5-fold increase of p-cPLA2S505, COX-2, and PGE2 levels in human prostate cancer cell lines. Pretreatment of cells with the COX-2 inhibitor SC-58125 or the EP4 antagonist AH-23848, or with an inhibitor of mTORC1 and mTORC2, Torin1, significantly reduced the Epac1-dependent increase of p-cPLA2 and COX-2, p-S6-kinaseT389, and p-AKTS473. In addition, Epac1-induced protein and DNA synthesis were greatly reduced upon pretreatment of cells with either COX-2, EP4, or mTOR inhibitors. Transfection of prostate cancer cells with Epac1 dsRNA, Raptor dsRNA, or Rictor dsRNA profoundly reduced Epac1-dependent increases in p-cPLA2 and COX-2. Conclusion We show that Epac1, a downstream effector of cAMP, functions as a pro-inflammatory modulator in prostate cancer cells and promotes cell proliferation and survival by upregulating Ras-MAPK, and PI 3-kinase-Akt-mTOR signaling. PMID:23646189

Increased fibroblast density in actinic cheilitis: association with tryptase-positive mast cells, actinic elastosis and epithelial p53 and COX-2 expression.

PubMed

Rojas, Isolde G; Boza, Yadira V; Spencer, Maria Loreto; Flores, Maritza; Martínez, Alejandra

2012-01-01

Actinic cheilitis (AC) is characterized by epithelial and connective tissue alterations caused by ultraviolet sunlight overexposure known as photodamage. Fibroblasts have been linked to photodamage and tumor progression during skin carcinogenesis; however, their role in early lip carcinogenesis remains unknown. The aim of this study was to assess the density of fibroblasts in AC and normal lip (NL) samples and determine their association with markers of lip photodamage. Fibroblasts, mast cells, p53, COX-2, and elastin were detected in NL (n = 20) and AC (n = 28) biopsies using immunohistochemistry/histochemistry. Mast cell and fibroblast density and epithelial p53 and COX-2 expression scores were then obtained. Elastosis was scored 1-4 according to elastin fiber density and tortuosity. Fibroblasts, mast cells, p53, COX-2, and elastosis were increased in AC as compared to NL (P < 0.001). Multivariate analysis showed an association between fibroblast and mast cell density at the papillary and reticular areas of AC and NL (P < 0.05). Papillary fibroblast density was also associated with epithelial p53 and COX-2 expression (P < 0.05). Increased fibroblast density, both papillary and reticular, was found in the high elastosis group (scores 3-4) as compared to the low elastosis group (scores 1-2) (P < 0.01). Increased reticular mast cell density was detected only in the high elastosis group (P < 0.01). Fibroblasts are increased in AC, and they are associated with mast cell density, epithelial p53 and COX-2 expression, and actinic elastosis. Therefore, fibroblasts may contribute to lip photodamage and could be considered useful markers of early lip carcinogenesis. © 2011 John Wiley & Sons A/S.

Role of the Lipoxygenase Pathway in RSV-induced Alternatively Activated Macrophages Leading to Resolution of Lung Pathology

PubMed Central

Shirey, Kari Ann; Lai, Wendy; Pletneva, Lioubov M.; Karp, Christopher L.; Divanovic, Senad; Blanco, Jorge C. G.; Vogel, Stefanie N.

2013-01-01

Resolution of severe RSV-induced bronchiolitis is mediated by alternatively activated macrophages (AA-Mϕ) that counteract cyclooxygenase (COX)-2-induced lung pathology. Herein, we report that RSV infection of 5-lipoxygenase (LO)−/− and 15-LO−/− macrophages or mice failed to elicit AA-Mϕ differentiation and concomitantly exhibited increased COX-2 expression. Further, RSV infection of 5-LO−/− mice resulted in enhanced lung pathology. Pharmacologic inhibition of 5-LO or 15-LO also blocked differentiation of RSV-induced AA-Mϕ in vitro and, conversely, treatment of 5-LO−/− macrophages with downstream products, lipoxin A4 (LXA4) and resolvin E1 (RvE1), but not leukotriene B4 (LTB4) or LTD4, partially restored expression of AA-Mϕ markers. Indomethacin blockade of COX activity in RSV-infected macrophages increased 5-LO, and 15-LO, as well as arginase-1 mRNA expression. Treatment of RSV-infected mice with indomethacin also resulted not only in enhanced lung arginase-1 mRNA expression and decreased COX-2, but also, decreased lung pathology in RSV-infected 5-LO−/− mice. Treatment of RSV-infected cotton rats with a COX-2-specific inhibitor resulted in enhanced lung 5-LO mRNA and AA-Mϕ marker expression. Together, these data suggest a novel therapeutic approach for RSV that promotes AA-Mϕ differentiation by activating the 5-LO pathway. PMID:24064666

CHIP involves in non-small cell lung cancer prognosis through VEGF pathway.

PubMed

Tingting, Qian; Jiao, Wang; Qingfeng, Wang; Yancheng, Liu; Shijun, Y U; Zhaoqi, Wang; Dongmei, Sun; ShiLong, Wang

2016-10-01

CHIP (c-terminal Hsp70-interacting protein) is an E3 ligase playing vital roles in various cancers. The VEGF pathway has become an important therapeutic target in non-small cell lung cancer (NSCLC). However, little is known about the role of CHIP and the relationship between CHIP and VEGF-VEGFR2 (VEGF receptor 2) pathway in NSCLC. In this study we aimed to investigate the clinical function of CHIP in NSCLC and explore the relevant regulatory mechanism. QRT-PCR was performed to detect CHIP expression in NSCLC tissues. The association of CHIP expression and clinical parameters was analyzed using the Chi-square test. Kaplan- Meier and Cox analyses were performed to identify the role of CHIP in the prognosis of NSCLC patients. ELISA test was used to detect the VEGF secretion of NSCLC cells and western blot were used to detected the protein expression of VEGFR2 in NSCLC cells. and the results revealed that CHIP expression was decreased in NSCLC tissues and significantly correlated with clinical stages, lymph node metastasis and distant metastasis (P<0.05). Moreover, Kaplan-Meier and Cox regression analyses showed that patients with negative expression of CHIP had a shorter survival time and CHIP could be an independent prognostic biomarker. In addition, ELISA tests showed that CHIP negatively regulated the secretion level of VEGF. Furthermore, western blot assay indicated that the VEGFR2 protein level was reduced after CHIP over-expression. Taken together, our findings demonstrate for the first time that CHIP may serve as a promising prognostic biomarker for NSCLC patients and it may be involved in NSCLC angiogenesis through regulating VEGF secretion and expression of VEGFR2. Copyright © 2016. Published by Elsevier Masson SAS.

Anti-Inflammatory Activities of Cinnamomum cassia Constituents In Vitro and In Vivo

PubMed Central

Liao, Jung-Chun; Deng, Jeng-Shyan; Chiu, Chuan-Sung; Hou, Wen-Chi; Huang, Shyh-Shyun; Shie, Pei-Hsin; Huang, Guang-Jhong

2012-01-01

We have investigated the anti-inflammatory effects of Cinnamomum cassia constituents (cinnamic aldehyde, cinnamic alcohol, cinnamic acid, and coumarin) using lipopolysaccharide (LPS)-stimulated mouse macrophage (RAW264.7) and carrageenan (Carr)-induced mouse paw edema model. When RAW264.7 macrophages were treated with cinnamic aldehyde together with LPS, a significant concentration-dependent inhibition of nitric oxide (NO), tumor necrosis factor (TNF-α), and prostaglandin E2 (PGE2) levels productions were detected. Western blotting revealed that cinnamic aldehyde blocked protein expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nuclear transcription factor kappa B (NF-κB), and IκBα, significantly. In the anti-inflammatory test, cinnamic aldehyde decreased the paw edema after Carr administration, and increased the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in the paw tissue. We also demonstrated cinnamic aldehyde attenuated the malondialdehyde (MDA) level and myeloperoxidase (MPO) activity in the edema paw after Carr injection. Cinnamic aldehyde decreased the NO, TNF-α, and PGE2 levels on the serum level after Carr injection. Western blotting revealed that cinnamic aldehyde decreased Carr-induced iNOS, COX-2, and NF-κB expressions in the edema paw. These findings demonstrated that cinnamic aldehyde has excellent anti-inflammatory activities and thus has great potential to be used as a source for natural health products. PMID:22536283

Formononetin inhibits enterovirus 71 replication by regulating COX- 2/PGE₂ expression.

PubMed

Wang, Huiqiang; Zhang, Dajun; Ge, Miao; Li, Zhuorong; Jiang, Jiandong; Li, Yuhuan

2015-03-01

The activation of ERK, p38 and JNK signal cascade in host cells has been demonstrated to up-regulate of enterovirus 71 (EV71)-induced cyclooxygenase-2 (COX-2)/ prostaglandins E2 (PGE₂) expression which is essential for viral replication. So, we want to know whether a compound can inhibit EV71 infection by suppressing COX-2/PGE₂ expression. The antiviral effect of formononetin was determined by cytopathic effect (CPE) assay and the time course assays. The influence of formononetin for EV71 replication was determined by immunofluorescence assay, western blotting assay and qRT-PCR assay. The mechanism of the antiviral activity of formononetin was determined by western blotting assay and ELISA assay. Formononetin could reduce EV71 RNA and protein synthesis in a dose-dependent manner. The time course assays showed that formononetin displayed significant antiviral activity both before (24 or 12 h) and after (0-6 h) EV71 inoculation in SK-N-SH cells. Formononetin was also able to prevent EV71-induced cytopathic effect (CPE) and suppress the activation of ERK, p38 and JNK signal pathways. Furthermore, formononetin could suppress the EV71-induced COX-2/PGE₂ expression. Also, formononetin exhibited similar antiviral activities against other members of Picornaviridae including coxsackievirus B2 (CVB2), coxsackievirus B3 (CVB3) and coxsackievirus B6 (CVB6). Formononetin could inhibit EV71-induced COX-2 expression and PGE₂ production via MAPKs pathway including ERK, p38 and JNK. Formononetin exhibited antiviral activities against some members of Picornaviridae. These findings suggest that formononetin could be a potential lead or supplement for the development of new anti-EV71 agents in the future.

Optimization of a nonviral transfection system to evaluate Cox-2 controlled interleukin-4 expression for osteoarthritis gene therapy in vitro.

PubMed

Lang, Annemarie; Neuhaus, Johannes; Pfeiffenberger, Moritz; Schröder, Erik; Ponomarev, Igor; Weber, Yvonne; Gaber, Timo; Schmidt, Michael F G

2014-01-01

Gene therapy appears to have the potential for achieving a long-term remedy for osteoarthritis (OA). However, there is a risk of adverse reactions, especially when using cytomegalovirus-controlled expression. To provide a safe application, we focused on the expression of therapeutic cytokines [e.g. interleukin (IL)-4] in a disease-responsive manner by use of the previously cloned Cox-2 promoter as 'genetic switch'. In the present study, we report the functionality of a controlled gene therapeutic system in an equine osteoarthritic cell model. Different nonviral transfection reagents were tested for their efficiency on equine chondrocytes stimulated with equine IL-1β or lipopolysaccharide to create an inflammatory environment. To optimize the transfection, we successfully redesigned the vector by excluding the internal ribosomal entry site (IRES). The functionality of our Cox-2 promoter construct with respect to expressing IL-4 was proven at the mRNA and protein levels and the anti-inflammatory potential of IL-4 was confirmed by analyzing the expression of IL-1β, IL-6, IL-8, matrix metalloproteinase (MMP)-1, MMP-3 and tumor necrosis factor (TNF)-α using a quantitative polymerase chain reaction. Nonviral transfection reagents yielded transfection rates from 21% to 44% with control vectors with and without IRES, respectively. Stimulation of equine chondrocytes resulted in a 20-fold increase of mRNA expression of IL-1β. Such exogenous stimulation of chondrocytes transfected with pNCox2-IL4 led to an increase of IL-4 mRNA expression, whereas expression of inflammatory mediators decreased. The timely link between these events confirms the anti-inflammatory potential of synthesized IL-4. We consider that this approach has significant potential for translation into a useful anti-inflammation therapy. Molecular tools such as the described therapeutic plasmid pave the way for a local-controlled, self-limiting gene therapy. Copyright © 2014 John Wiley & Sons, Ltd.