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1

Geniposide suppresses LPS-induced nitric oxide, PGE2 and inflammatory cytokine by downregulating NF-?B, MAPK and AP-1 signaling pathways in macrophages.  

PubMed

Inflammatory responses are important to host immune reactions, but uncontrolled inflammatory mediators may aid in the pathogenesis of other inflammatory diseases. Geniposide, an iridoid glycoside found in the herb gardenia, is believed to have broad-spectrum anti-inflammatory effects in murine models but its mechanism of action is unclear. We investigated the action of this compound in murine macrophages stimulated by lipopolysaccharide (LPS), as the stimulation of macrophages by LPS is known to induce inflammatory reactions. We determined the effect of geniposide on LPS-induced production of the inflammatory mediators, nitric oxide (NO) and prostaglandin E2 (PGE2), the mRNA and protein expression of the NO and PGE2 synthases, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), respectively, and the mRNA and protein expression of the inflammatory cytokine, tumor necrosis factor-? (TNF-?) and interleukin-6 (IL-6). Furthermore, nuclear factor (NF)-?B, mitogen-activated protein kinase (MAPK) and activator protein (AP)-1 activity were assayed. To understand the action of geniposide on the NF-?B and MAPK pathways, we studied the effect of NF-?B and MAPK inhibitors on the LPS-induced production of NO, PGE2 and TNF-?. Our findings clearly showed that geniposide mainly exerts its anti-inflammatory effects by inhibiting the LPS-induced NF-?B, MAPK and AP-1 signaling pathways in macrophages, which subsequently reduces overexpression of the inducible enzymes iNOS and COX-2 and suppresses the expression and release of the inflammatory factors, TNF-?, IL-6, NO and PGE2. Thus, geniposide shows promise as a therapeutic agent in inflammatory diseases. PMID:24735815

Shi, Qinghai; Cao, Jinjun; Fang, Li; Zhao, Hongyan; Liu, Zhengxiang; Ran, Jihua; Zheng, Xinchuan; Li, Xiaoling; Zhou, Yu; Ge, Di; Zhang, Hongming; Wang, Li; Ran, Ying; Fu, Jianfeng

2014-06-01

2

?-Phenylethyl and 8-methylsulphinyloctyl isothiocyanates, constituents of watercress, suppress LPS induced production of nitric oxide and prostaglandin E2 in RAW 264.7 macrophages  

Microsoft Academic Search

?-Phenylethyl (PEITC) and 8-methylsulphinyloctyl isothiocyanates (MSO) represent two phytochemical constituents present in watercress Rorripa nasturtium aquaticum, with known chemopreventative properties. In the present investigation, we examined whether PEITC and MSO could modulate the inflammatory response of Raw 264.7 macrophages to bacterial lipopolysaccharide (LPS) by assessment of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression. Overproduction of both nitric oxide

Peter Rose; Yen Kim Won; Choon Nam Ong; Matt Whiteman

2005-01-01

3

Stevioside protects LPS-induced acute lung injury in mice.  

PubMed

Stevioside, a diterpene glycoside component of Stevia rebaudiana, has been known to exhibit anti-inflammatory properties. To evaluate the effect and the possible mechanism of stevioside in lipopolysaccharide (LPS)-induced acute lung injury, male BALB/c mice were pretreated with stevioside or dexamethasone 1 h before intranasal instillation of LPS. Seven hours later, tumor necrosis factor-?, interleukin-1?, and interleukin-6 in bronchoalveolar lavage fluid (BALF) were measured by using enzyme-linked immunosorbent assay. The number of total cells, neutrophils, and macrophages in the BALF were also determined. The right lung was excised for histological examination and analysis of myeloperoxidase activity and nitrate/nitrite content. Cyclooxygenase 2 (COX-2), inducible NO synthase (iNOS), nuclear factor-kappa B (NF-?B), inhibitory kappa B protein were detected by western blot. The results showed that stevioside markedly attenuated the LPS-induced histological alterations in the lung. Stevioside inhibited the production of pro-inflammatory cytokines and the expression of COX-2 and iNOS induced by LPS. In addition, not only was the wet-to-dry weight ratio of lung tissue significantly decreased, the number of total cells, neutrophils, and macrophages in the BALF were also significantly reduced after treatment with stevioside. Moreover, western blotting showed that stevioside inhibited the phosphorylation of I?B-? and NF-?B caused by LPS. Taken together, our results suggest that anti-inflammatory effect of stevioside against the LPS-induced acute lung injury may be due to its ability of inhibition of the NF-?B signaling pathway. Stevioside may be a promising potential therapeutic reagent for acute lung injury treatment. PMID:22968433

Yingkun, Nie; Zhenyu, Wang; Jing, Lin; Xiuyun, Lu; Huimin, Yu

2013-02-01

4

Inhibition of IRAK-4 activity for rescuing endotoxin LPS-induced septic mortality in mice by lonicerae flos extract  

SciTech Connect

Highlights: •Lonicerae flos extract (HS-23) is a clinical candidate, Phase I for sepsis treatment. •Here, HS-23 or its major constituents rescued LPS-induced septic mortality in mice. •As a mechanism, they directly inhibited IRAK-4-catalyzed kinase activity. •Thus, they suppressed LPS-induced expression of NF-?B/AP-1-target inflammatory genes. -- Abstract: Lonicerae flos extract (HS-23) is a clinical candidate currently undergoing Phase I trial in lipopolysaccharide (LPS)-injected healthy human volunteers, but its molecular basis remains to be defined. Here, we investigated protective effects of HS-23 or its major constituents on Escherichia coli LPS-induced septic mortality in mice. Intravenous treatment with HS-23 rescued LPS-intoxicated C57BL/6J mice under septic conditions, and decreased the levels of cytokines such as tumor necrosis factor ? (TNF-?), interleukin (IL)-1? and high-mobility group box-1 (HMGB-1) in the blood. Chlorogenic acid (CGA) and its isomers were assigned as major constituents of HS-23 in the protection against endotoxemia. As a molecular mechanism, HS-23 or CGA isomers inhibited endotoxin LPS-induced autophosphorylation of the IL-1 receptor-associated kinase 4 (IRAK-4) in mouse peritoneal macrophages as well as the kinase activity of IRAK-4 in cell-free reactions. HS-23 consequently suppressed downstream pathways critical for LPS-induced activation of nuclear factor (NF)-?B or activating protein 1 (AP-1) in the peritoneal macrophages. HS-23 also inhibited various toll-like receptor agonists-induced nitric oxide (NO) production, and down-regulated LPS-induced expression of NF-?B/AP-1-target inflammatory genes in the cells. Taken together, HS-23 or CGA isomers exhibited anti-inflammatory therapy against LPS-induced septic mortality in mice, at least in part, mediated through the inhibition of IRAK-4.

Park, Sun Hong; Roh, Eunmiri [College of Pharmacy, Chungbuk National University, Cheongju 361-763 (Korea, Republic of)] [College of Pharmacy, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Kim, Hyun Soo [Pharmaceutical R and D Center, Huons Co., Ltd., Anyang (Korea, Republic of)] [Pharmaceutical R and D Center, Huons Co., Ltd., Anyang (Korea, Republic of); Baek, Seung-Il [College of Pharmacy, Chungbuk National University, Cheongju 361-763 (Korea, Republic of)] [College of Pharmacy, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Choi, Nam Song [Pharmaceutical R and D Center, Huons Co., Ltd., Anyang (Korea, Republic of)] [Pharmaceutical R and D Center, Huons Co., Ltd., Anyang (Korea, Republic of); Kim, Narae; Hwang, Bang Yeon; Han, Sang-Bae [College of Pharmacy, Chungbuk National University, Cheongju 361-763 (Korea, Republic of)] [College of Pharmacy, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Kim, Youngsoo, E-mail: youngsoo@chungbuk.ac.kr [College of Pharmacy, Chungbuk National University, Cheongju 361-763 (Korea, Republic of)] [College of Pharmacy, Chungbuk National University, Cheongju 361-763 (Korea, Republic of)

2013-12-13

5

Carabrol suppresses LPS-induced nitric oxide synthase expression by inactivation of p38 and JNK via inhibition of I-{kappa}B{alpha} degradation in RAW 264.7 cells  

SciTech Connect

Carabrol, isolated from Carpesium macrocephalum, showed anti-inflammatory potential in LPS-induced RAW 264.7 murine macrophages. In present study, carabrol demonstrated the inhibitory activity on pro-inflammatory cytokines such as IL-1{beta}, IL-6 and TNF-{alpha}. In addition, mRNA and protein levels of iNOS and COX-2 were reduced by carabrol. Molecular analysis revealed that these suppressive effects were correlated with the inactivation of p38 and JNK via inhibition of NF-{kappa}B activation. Immunoblotting showed that carabrol suppressed LPS-induced degradation of I-{kappa}B{alpha} and decreased nuclear translocation of p65. Taken together, these results suggest that carabrol can be a modulator of pro-inflammatory signal transduction pathway in RAW 264.7 cells.

Lee, Hwa Jin [Department of Life Science, Research Center for Women's Diseases, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of)] [Department of Life Science, Research Center for Women's Diseases, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of); Lim, Hyo Jin; Lee, Da Yeon [College of Pharmacy, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of)] [College of Pharmacy, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of); Jung, Hyeyoun [Department of Life Science, Research Center for Women's Diseases, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of)] [Department of Life Science, Research Center for Women's Diseases, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of); Kim, Mi-Ran; Moon, Dong-Cheul [College of Pharmacy, Chungbuk National University, Cheungju 361-763 (Korea, Republic of)] [College of Pharmacy, Chungbuk National University, Cheungju 361-763 (Korea, Republic of); Kim, Keun Il; Lee, Myeong-Sok [Department of Life Science, Research Center for Women's Diseases, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of)] [Department of Life Science, Research Center for Women's Diseases, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of); Ryu, Jae-Ha, E-mail: ryuha@sookmyung.ac.kr [College of Pharmacy, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of)] [College of Pharmacy, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of)

2010-01-15

6

The Effect of the Aerial Part of Lindera akoensis on Lipopolysaccharides (LPS)-Induced Nitric Oxide Production in RAW264.7 Cells  

PubMed Central

Four new secondary metabolites, 3?-((E)-Dodec-1-enyl)-4?-hydroxy-5?-methyldihydrofuran-2-one (1), linderinol (6), 4?-O-methylkaempferol 3-O-?-l-(4?-E-p-coumaroyl)rhamnoside (11) and kaempferol 3-O-?-l-(4?-Z-p-coumaroyl) rhamnoside (12) with eleven known compounds—3-epilistenolide D1 (2), 3-epilistenolide D2 (3), (3Z,4?,5?)-3-(dodec-11-ynylidene)-4-hydroxy-5-methylbutanolide (4), (3E,4?,5?)-3-(dodec-11-ynylidene)-4-hydroxy-5-methylbutanolide (5), matairesinol (7), syringaresinol (8), (+)-pinoresinol (9), salicifoliol (10), 4?-p-coumaroylafzelin (13), catechin (14) and epicatechin (15)—were first isolated from the aerial part of Lindera akoensis. Their structures were determined by detailed analysis of 1D- and 2D-NMR spectroscopic data. All of the compounds isolated from Lindera akoensis showed that in vitro anti-inflammatory activity decreases the LPS-stimulated production of nitric oxide (NO) in RAW 264.7 cell, with IC50 values of 4.1–413.8 ?M. PMID:23624606

Yang, Chung-Ping; Huang, Guan-Jhong; Huang, Hui-Chi; Chen, Yu-Chang; Chang, Chi-I; Wang, Sheng-Yang; Chang, Hsun-Shuo; Tseng, Yen-Hsueh; Chien, Shih-Chang; Kuo, Yueh-Hsiung

2013-01-01

7

Ipomoea obscura (L.) enhances the functions of immunological effector cells, inhibits proinflammatory cytokines and nitric oxide production by LPS induced macrophages.  

PubMed

Most of the synthetic chemotherapeutic agents available today are immunosuppressant, cytotoxic and exerts variety of side effects. Botanical based immunomodulators are often employed as supportive or adjuvant therapy to overcome the undesired effects of cytotoxic chemotherapeutic agents and to restore normal health. The methanolic extract of traditionally important medicinal plant Ipomoea obscura exhibited immunomodulatory activity in BALB/c mice. Intraperitoneal administration of five doses of the extract (10 mg/kg body wt) was found to enhance the total WBC count (13912 cells/mm(3)) on the 12(th) day, bone marrow cellularity (28.9 x 10(6)cells/femur) and number of alpha-esterase positive cells (1246 cells/4000 cells). Treatment with the extract along with the antigen, sheep red blood cells (SRBC), produced an enhancement in the circulating antibody titer and the number of plaque forming cells (PFC) in the spleen. Maximum number of PFC (267.6 PFC/10(6) spleen cells) was obtained on the 6(th) day. At the same time administration of Ipomoea obscura extract significantly reduced the elevated levels of proinflammatory cytokines and nitric oxide production by lipopolysaccharide stimulated macrophages. These results indicate the immunomodulatory activity of the alcoholic extract of Ipomoea obscura. PMID:18798043

Hamsa, T P; Kuttan, Girija

2009-06-01

8

Sulfated Chitosan Oligosaccharides Suppress LPS-Induced NO Production via JNK and NF-?B Inactivation.  

PubMed

Various biological effects have been reported for sulfated chitosan oligosaccharides, but the molecular mechanisms of action of their anti-inflammatory effects are still unknown. This study aimed to evaluate the anti-inflammatory effects of sulfated chitosan oligosaccharides and to elucidate the possible mechanisms of action. The results showed that pretreated low molecular weight sulfated chitosan oligosaccharides inhibited the production of nitric oxide (NO) and inflammatory cytokines such as IL-6 and TNF-? in lipopolysaccharide (LPS)-activated RAW264.7 cells. The sulfated chitosan oligosaccharides also suppressed inducible nitric oxide synthase (iNOS), phosphorylation of JNK and translocation of p65, a subunit of NF-?B, into the nucleus by inhibiting degradation of I?B-?. Our investigation suggests sulfated chitosan oligosaccharides inhibit IL-6/TNF-? in LPS-induced macrophages, regulated by mitogen-activated protein kinases (MAPKs) pathways dependent on NF-?B activation. PMID:25387351

Kim, Jung-Hyun; Kim, Yon-Suk; Hwang, Jin-Woo; Han, Young-Ki; Lee, Jung-Suck; Kim, Se-Kwon; Jeon, You-Jin; Moon, Sang-Ho; Jeon, Byong-Tae; Bahk, Young Yil; Park, Pyo-Jam

2014-01-01

9

Inhibition of IRAK-4 activity for rescuing endotoxin LPS-induced septic mortality in mice by lonicerae flos extract.  

PubMed

Lonicerae flos extract (HS-23) is a clinical candidate currently undergoing Phase I trial in lipopolysaccharide (LPS)-injected healthy human volunteers, but its molecular basis remains to be defined. Here, we investigated protective effects of HS-23 or its major constituents on Escherichia coli LPS-induced septic mortality in mice. Intravenous treatment with HS-23 rescued LPS-intoxicated C57BL/6J mice under septic conditions, and decreased the levels of cytokines such as tumor necrosis factor ? (TNF-?), interleukin (IL)-1? and high-mobility group box-1 (HMGB-1) in the blood. Chlorogenic acid (CGA) and its isomers were assigned as major constituents of HS-23 in the protection against endotoxemia. As a molecular mechanism, HS-23 or CGA isomers inhibited endotoxin LPS-induced autophosphorylation of the IL-1 receptor-associated kinase 4 (IRAK-4) in mouse peritoneal macrophages as well as the kinase activity of IRAK-4 in cell-free reactions. HS-23 consequently suppressed downstream pathways critical for LPS-induced activation of nuclear factor (NF)-?B or activating protein 1 (AP-1) in the peritoneal macrophages. HS-23 also inhibited various toll-like receptor agonists-induced nitric oxide (NO) production, and down-regulated LPS-induced expression of NF-?B/AP-1-target inflammatory genes in the cells. Taken together, HS-23 or CGA isomers exhibited anti-inflammatory therapy against LPS-induced septic mortality in mice, at least in part, mediated through the inhibition of IRAK-4. PMID:24269819

Park, Sun Hong; Roh, Eunmiri; Kim, Hyun Soo; Baek, Seung-Il; Choi, Nam Song; Kim, Narae; Hwang, Bang Yeon; Han, Sang-Bae; Kim, Youngsoo

2013-12-13

10

SOCS1\\/JAB Is a Negative Regulator of LPS-Induced Macrophage Activation  

Microsoft Academic Search

Bacterial lipopolysaccharide (LPS) triggers innate immune responses through Toll-like receptor (TLR) 4. We show here that the suppressor of cytokine-signaling-1 (SOCS1\\/JAB) is rapidly induced by LPS and negatively regulates LPS signaling. SOCS1+\\/? mice or SOCS1?\\/? mice with interferon-? (IFN?)-deficient background were more sensitive to LPS-induced lethal effects than were wild-type littermates. LPS-induced NO2? synthesis and TNF? production were augmented in

Ichiko Kinjyo; Toshikatsu Hanada; Kyoko Inagaki-Ohara; Hiroyuki Mori; Daisuke Aki; Masanobu Ohishi; Hiroki Yoshida; Masato Kubo; Akihiko Yoshimura

2002-01-01

11

Vascular smooth muscle cells on Matrigel as a model for LPS-induced hypocontractility and NO formation.  

PubMed

Treatment of vascular tissue with low levels of lipopolysaccharide (LPS) induces nitric oxide synthase (NOS) activity and diminishes vascular contractility. However, in cultured vascular smooth muscle cells (VSMC), very high doses of LPS or the combination of LPS with cytokines are required for the induction of nitric oxide (NO) formation. The aims of this study were to establish a cell model to investigate LPS-induced hypocontractility and NO production and to test the hypothesis that responses of VSMC to LPS are differentiation regulated. We used Matrigel basement membrane matrix to maintain VSMC differentiation and found that VSMC cultured on Matrigel retained significant contractility in response to KCl stimulation. Incubation of VSMC with low levels of LPS(1-100 ng/ml) induced NOS mRNA and protein, induced NO production, and decreased cell contractility in a time- and dose-dependent fashion. The NOS inhibitor NG-nitro-L-arginine methyl ester (L-NAME) partially restored LPS-treated VSMC contractility, whereas L-arginine reversed the contractility-restoring effect of L-NAME. These results suggest that VSMC grown on Matrigel are a useful experimental model for investigations into signal transduction mechanisms responsible for LPS-induced vascular hypocontractility. PMID:9038981

Li, S; Fan, S X; McKenna, T M

1997-01-01

12

Silibinin Inhibits LPS-Induced Macrophage Activation by Blocking p38 MAPK in RAW 264.7 Cells  

PubMed Central

We demonstrate herein that silibinin, a polyphenolic flavonoid compound isolated from milk thistle (Silybum marianum), inhibits LPS-induced activation of macrophages and production of nitric oxide (NO) in RAW 264.7 cells. Western blot analysis showed silibinin inhibits iNOS gene expression. RT-PCR showed that silibinin inhibits iNOS, TNF-?, and IL1?. We also showed that silibinin strongly inhibits p38 MAPK phosphorylation, whereas the ERK1/2 and JNK pathways are not inhibited. The p38 MAPK inhibitor abrogated the LPS-induced nitrite production, whereas the MEK-1 inhibitor did not affect the nitrite production. A molecular modeling study proposed a binding pose for silibinin targeting the ATP binding site of p38 MAPK (1OUK). Collectively, this series of experiments indicates that silibinin inhibits macrophage activation by blocking p38 MAPK signaling. PMID:24244809

Youn, Cha Kyung; Park, Seon Joo; Lee, Min Young; Cha, Man Jin; Kim, Ok Hyeun; You, Ho Jin; Chang, In Youp; Yoon, Sang Pil; Jeon, Young Jin

2013-01-01

13

Pyrrolizidine alkaloids from Liparis nervosa with inhibitory activities against LPS-induced NO production in RAW264.7 macrophages.  

PubMed

Six pyrrolizidine alkaloids were isolated from the whole herb of Liparis nervosa together with two previously known ones. Their structures were elucidated by extensive spectroscopic analyses and chemical reactions. The cytotoxicity of the isolates was evaluated against A549, HepG2, and MCF-7 human cancer cell lines; however, no significant growth inhibition was observed. All compounds were evaluated for the inhibition of LPS-induced nitric oxide (NO) production in RAW264.7 macrophages, and most significantly inhibited NO production with IC50 values in the range of 2.16-38.25 ?M. PMID:23571028

Huang, Shuai; Zhou, Xian-li; Wang, Cui-juan; Wang, You-song; Xiao, Feng; Shan, Lian-hai; Guo, Zhi-yun; Weng, Jie

2013-09-01

14

Myrrh Inhibits LPS-Induced Inflammatory Response and Protects from Cecal Ligation and Puncture-Induced Sepsis  

PubMed Central

Myrrh has been used as an antibacterial and anti-inflammatory agent. However, effect of myrrh on peritoneal macrophages and clinically relevant models of septic shock, such as cecal ligation and puncture (CLP), is not well understood. Here, we investigated the inhibitory effect and mechanism(s) of myrrh on inflammatory responses. Myrrh inhibited LPS-induced productions of inflammatory mediators such as nitric oxide, prostaglandin E2, and tumor necrosis factor-? but not of interleukin (IL)-1? and IL-6 in peritoneal macrophages. In addition, Myrrh inhibited LPS-induced activation of c-jun NH2-terminal kinase (JNK) but not of extracellular signal-regulated kinase (ERK), p38, and nuclear factor-?B. Administration of Myrrh reduced the CLP-induced mortality and bacterial counts and inhibited inflammatory mediators. Furthermore, administration of Myrrh attenuated CLP-induced liver damages, which were mainly evidenced by decreased infiltration of leukocytes and aspartate aminotransferase/alanine aminotransferase level. Taken together, these results provide the evidence for the anti-inflammatory and antibacterial potential of Myrrh in sepsis. PMID:21826187

Kim, Min-Sun; Bae, Gi-Sang; Park, Kyoung-Chel; Koo, Bon Soon; Kim, Byung-Jin; Lee, Hye-Jin; Seo, Sang-Wan; Shin, Yong Kook; Jung, Won-Seok; Cho, Jung-Hee; Kim, Youn-Chul; Kim, Tae-Hyeon; Song, Ho-Joon; Park, Sung-Joo

2012-01-01

15

Myrrh inhibits LPS-induced inflammatory response and protects from cecal ligation and puncture-induced sepsis.  

PubMed

Myrrh has been used as an antibacterial and anti-inflammatory agent. However, effect of myrrh on peritoneal macrophages and clinically relevant models of septic shock, such as cecal ligation and puncture (CLP), is not well understood. Here, we investigated the inhibitory effect and mechanism(s) of myrrh on inflammatory responses. Myrrh inhibited LPS-induced productions of inflammatory mediators such as nitric oxide, prostaglandin E(2), and tumor necrosis factor-? but not of interleukin (IL)-1? and IL-6 in peritoneal macrophages. In addition, Myrrh inhibited LPS-induced activation of c-jun NH(2)-terminal kinase (JNK) but not of extracellular signal-regulated kinase (ERK), p38, and nuclear factor-?B. Administration of Myrrh reduced the CLP-induced mortality and bacterial counts and inhibited inflammatory mediators. Furthermore, administration of Myrrh attenuated CLP-induced liver damages, which were mainly evidenced by decreased infiltration of leukocytes and aspartate aminotransferase/alanine aminotransferase level. Taken together, these results provide the evidence for the anti-inflammatory and antibacterial potential of Myrrh in sepsis. PMID:21826187

Kim, Min-Sun; Bae, Gi-Sang; Park, Kyoung-Chel; Koo, Bon Soon; Kim, Byung-Jin; Lee, Hye-Jin; Seo, Sang-Wan; Shin, Yong Kook; Jung, Won-Seok; Cho, Jung-Hee; Kim, Youn-Chul; Kim, Tae-Hyeon; Song, Ho-Joon; Park, Sung-Joo

2012-01-01

16

A central role for the mammalian target of rapamycin in LPS-induced anorexia in mice.  

PubMed

Bacterial lipopolysaccharide (LPS), also known as endotoxin, induces profound anorexia. However, the LPS-provoked pro-inflammatory signaling cascades and the neural mechanisms underlying the development of anorexia are not clear. Mammalian target of rapamycin (mTOR) is a key regulator of metabolism, cell growth, and protein synthesis. This study aimed to determine whether the mTOR pathway is involved in LPS-induced anorexia. Effects of LPS on hypothalamic gene/protein expression in mice were measured by RT-PCR or western blotting analysis. To determine whether inhibition of mTOR signaling could attenuate LPS-induced anorexia, we administered an i.c.v. injection of rapamycin, an mTOR inhibitor, on LPS-treated male mice. In this study, we showed that LPS stimulates the mTOR signaling pathway through the enhanced phosphorylation of mTOR(Ser2448) and p70S6K(Thr389). We also showed that LPS administration increased the phosphorylation of FOXO1(Ser256), the p65 subunit of nuclear factor kappa B (P<0.05), and FOXO1/3a(Thr) (24) (/) (32) (P<0.01). Blocking the mTOR pathway significantly attenuated the LPS-induced anorexia by decreasing the phosphorylation of p70S6K(Thr389), FOXO1(Ser256), and FOXO1/3a(Thr) (24) (/) (32). These results suggest promising approaches for the prevention and treatment of LPS-induced anorexia. PMID:25349249

Yue, Yunshuang; Wang, Yi; Li, Dan; Song, Zhigang; Jiao, Hongchao; Lin, Hai

2015-01-01

17

Inhibition of LPS-induced splenocyte proliferation by ortho-substituted polychlorinated biphenyl congeners.  

PubMed

Polychlorinated biphenyls (PCBs) are persistent environmental contaminants, and their ubiquitous nature has prompted studies of their potential health hazards. As a result of their lipophilic nature, PCBs accumulate in breast milk and subsequently affect the health of offspring of exposed individuals. Biological effects of PCBs in animals have mostly been attributed to coplanar congeners, although effects of ortho congeners also have been demonstrated. To investigate the relationship of immunotoxicity and chlorine substitution pattern, the effects of PCB congeners and mixtures of ortho and non-ortho-substituted constituents of Aroclor 1242 on splenocytes from C57B1/6 mice were examined. The immunotoxic endpoints investigated included splenocyte viability, lipopolysaccharide (LPS)-induced splenocyte proliferation, and LPS-induced antibody secretion. Congeners with multiple ortho chlorines preferentially inhibited splenocyte proliferation as compared with non- or mono-ortho-substituted congeners. However, mixtures of non- and mono-ortho-substituted congeners and multi-ortho-substituted congeners inhibited LPS-induced splenocyte proliferation and antibody secretion at similar concentrations. Exposure of splenocytes to these mixtures did not activate the aryl hydrocarbon receptor (AhR) signal transduction pathway. These results suggest individual multi-ortho-substituted congeners preferentially inhibit LPS-induced splenocyte proliferation, while congeners not exhibiting an effect individually may have additive effects in a mixture to produce an immunotoxic response through an AhR-independent pathway. PMID:12767701

Smithwick, L Ashley; Smith, Andrew; Quensen, John F; Stack, Allison; London, Lucille; Morris, Pamela J

2003-06-30

18

EFFECTS OF SYSTEMIC NEUTROPHIL DEPLETION ON LPS-INDUCED AIRWAY DISEASE  

EPA Science Inventory

Effects of Systemic Neutrophil Depletion on LPS-induced Airway Disease Jordan D. Savov, Stephen H. Gavett*, David M. Brass, Daniel L. Costa*, David A. Schwartz Pulmonary and Critical Care Division, Dept of Medicine ? Duke University Medical Center * National Health and E...

19

Surfactant Protein-A Modulates LPS-Induced TLR4 Localization and Signaling via ?-Arrestin 2  

PubMed Central

The soluble C-type lectin surfactant protein (SP)-A mediates lung immune responses partially via its direct effects on alveolar macrophages (AM), the main resident leukocytes exposed to antigens. SP-A modulates the AM threshold of lipopolysaccharide (LPS) activity towards an anti-inflammatory phenotype both in vitro and in vivo through various mechanisms. LPS responses are tightly regulated via distinct pathways including subcellular TLR4 localization and thus ligand sensing. The cytosolic scaffold and signaling protein ?-arrestin 2 acts as negative regulator of LPS-induced TLR4 activation. Here we show that SP-A neither increases TLR4 abundancy nor co-localizes with TLR4 in primary AM. SP-A significantly reduces the LPS-induced co-localization of TLR4 with the early endosome antigen (EEA) 1 by promoting the co-localization of TLR4 with the post-Golgi compartment marker Vti1b in freshly isolated AM from rats and wild-type (WT) mice, but not in ?-arrestin 2?/? AM. Compared to WT mice pulmonary LPS-induced TNF-? release in ?-arrestin 2?/? mice is accelerated and enhanced and exogenous SP-A fails to inhibit both lung LPS-induced TNF-? release and TLR4/EEA1 positioning. SP-A, but not LPS, enhances ?-arrestin 2 protein expression in a time-dependent manner in primary rat AM. The constitutive expression of ?-arrestin 2 in AM from SP-A?/? mice is significantly reduced compared to SP-A+/+ mice and is rescued by SP-A. Prolonged endosome retention of LPS-induced TLR4 in AM from SP-A?/? mice is restored by exogenous SP-A, and is antagonized by ?-arrestin 2 blocking peptides. LPS induces ?-arrestin 2/TLR4 association in primary AM which is further enhanced by SP-A. The data demonstrate that SP-A modulates LPS-induced TLR4 trafficking and signaling in vitro and in vivo engaging ?-arrestin 2. PMID:23536892

Sender, Vicky; Lang, Linda; Stamme, Cordula

2013-01-01

20

Effects of voluntary wheel running on LPS-induced sickness behavior in aged mice.  

PubMed

Peripheral stimulation of the innate immune system with LPS causes exaggerated neuroinflammation and prolonged sickness behavior in aged mice. Regular moderate intensity exercise has been shown to exert anti-inflammatory effects that may protect against inappropriate neuroinflammation and sickness in aged mice. The purpose of this study was to test the hypothesis that voluntary wheel running would attenuate LPS-induced sickness behavior and proinflammatory cytokine gene expression in ~22-month-old C57BL/6J mice. Mice were housed with a running wheel (VWR), locked-wheel (Locked), or no wheel (Standard) for 10 weeks, after which they were intraperitoneally injected with LPS across a range of doses (0.02, 0.08, 0.16, 0.33 mg/kg). VWR mice ran on average 3.5 km/day and lost significantly more body weight and body fat, and increased their forced exercise tolerance compared to Locked and Shoebox mice. VWR had no effect on LPS-induced anorexia, adipsia, weight-loss, or reductions in locomotor activity at any LPS dose when compared to Locked and Shoebox groups. LPS induced sickness behavior in a dose-dependent fashion (0.33>0.02 mg/kg). Twenty-four hours post-injection (0.33 mg/kg LPS or Saline) we found a LPS-induced upregulation of whole brain TNF?, IL-1?, and IL-10 mRNA, and increased IL-1? and IL-6 in the spleen and liver; these effects were not attenuated by VWR. We conclude that VWR does not reduce LPS-induced exaggerated or prolonged sickness behavior in aged animals, or 24h post-injection (0.33 mg/kg LPS or Saline) brain and peripheral proinflammatory cytokine gene expression. The necessity of the sickness response is critical for survival and may outweigh the subtle benefits of exercise training in aged animals. PMID:23277090

Martin, Stephen A; Pence, Brandt D; Greene, Ryan M; Johnson, Stephanie J; Dantzer, Robert; Kelley, Keith W; Woods, Jeffrey A

2013-03-01

21

Angiopoietin-1 variant reduces LPS-induced microvascular dysfunction in a murine model of sepsis  

PubMed Central

Introduction Severe sepsis is characterised by intravascular or extravascular infection with microbial agents, systemic inflammation and microcirculatory dysfunction, leading to tissue damage, organ failure and death. The growth factor angiopoietin (Ang-1) has therapeutic potential but recombinant Ang-1 tends to aggregate and has a short half-life in vivo. This study aimed to investigate the acute effects of the more stable Ang-1 variant matrilin-1-angiopoietin-1 (MAT.Ang-1) on the function of the microcirculation in an experimental model of sepsis, and whether any protection by MAT-Ang-1 was associated with modulation of inflammatory cytokines, angiogenic factors or the endothelial nitric oxide synthase (eNOS)-Akt and vascular endothelial (VE)-cadherin pathways. Methods Aluminium window chambers were implanted into the dorsal skinfold of male C3H/HeN mice (7 to 10 weeks old) to expose the striated muscle microcirculation. Endotoxemia was induced by intraperitoneal injection of lipopolysaccharide (LPS, 1 mg/kg at 0 and 19 hours). MAT.Ang-1 was administered intravenously 20 hours after the onset of sepsis. Microcirculatory function was evaluated by intravital microscopy and Doppler fluximetry. Results Endotoxemia resulted in macromolecular leak, which was ameliorated by MAT.Ang-1 post-treatment. LPS induced a dramatic reduction in tissue perfusion, which was improved by MAT.Ang-1. Proteome profiler array analysis of skeletal muscle also demonstrated increased inflammatory and reduced angiogenic factors during endotoxemia. MAT.Ang-1 post-treatment reduced the level of IL-1? but did not significantly induce the expression of angiogenic factors. MAT.Ang-1 alone did not induce leak or increase angiogenic factors but did reduce vascular endothelial growth factor expression in controls. Conclusion Administration of MAT.Ang-1 after the onset of sepsis protects the microcirculation from endotoxemia-induced vascular dysfunction through reducing inflammation but without pro-angiogenic actions, thus representing a novel, potential pharmacotherapeutic agent for the treatment of sepsis. PMID:23036162

2012-01-01

22

Polychlorinated biphenyl mixtures (Aroclors) inhibit LPS-induced murine splenocyte proliferation in vitro  

Microsoft Academic Search

The immune system is believed to be a sensitive indicator for adverse polychlorinated biphenyl (PCB)-induced health effects. Four commercial PCB mixtures (Aroclors) or six individual PCB congeners were evaluated for their effect on splenocyte viability and lipopolysaccharide (LPS)-induced splenocyte proliferation in vitro in two strains of mice, C57B1\\/6 (high affinity aromatic hydrocarbon receptor (AhR) complex) and DBA\\/J (low affinity AhR

Allison Schulze Stack; Sanja Altman-Hamamdzic; Pamela J. Morris; Steven D. London; Lucille London

1999-01-01

23

Attenuation of LPS-induced lung inflammation by glucosamine in rats.  

PubMed

Acute inflammation is often observed during acute lung injury (ALI) and acute respiratory distress syndrome. Glucosamine is known to act as an anti-inflammatory molecule. The effects of glucosamine on acute lung inflammation and its associated mechanisms remain unclear. The present study sought to address how glucosamine plays an anti-inflammatory role in acute lung inflammation in vivo and in vitro. Using the LPS intratracheal instillation-elicited rat lung inflammation model, we found that glucosamine attenuated pulmonary edema and polymorphonuclear leukocyte infiltration, as well as the production of TNF-?, IL-1?, cytokine-induced neutrophil chemoattractant (CINC)-1, macrophage inflammatory protein (MIP)-2, and nitric oxide (NO) in the bronchoalveolar lavage fluid (BALF) and in the cultured medium of BALF cells. The expression of TNF-?, IL-1?, IFN-?, CINC-1, MIP-2, monocyte chemotactic protein-1, and inducible NO synthase (iNOS) in LPS-inflamed lung tissue was also suppressed by glucosamine. Using the rat alveolar epithelial cell line L2, we noted that the cytokine mixture (cytomix)-regulated production and mRNA expression of CINC-1 and MIP-2, NO production, the protein and mRNA expression of iNOS, iNOS mRNA stability, and iNOS promoter activity were all inhibited by glucosamine. Furthermore, glucosamine reduced LPS-mediated NF-?B signaling by decreasing I?B phosphorylation, p65 nuclear translocation, and NF-?B reporter activity. Overexpression of the p65 subunit restored the inhibitory action of glucosamine on cytomix-regulated NO production and iNOS expression. In conclusion, glucosamine appears to act as an anti-inflammatory molecule in LPS-induced lung inflammation, at least in part by targeting the NF-?B signaling pathway. PMID:23898954

Chuang, Kun-Han; Peng, Yen-Chun; Chien, Han-Yun; Lu, Meng-Lun; Du, Hsin-I; Wu, Yuh-Lin

2013-12-01

24

Nucleotide receptor P2RX7 stimulation enhances LPS-induced interferon-? production in murine macrophages  

PubMed Central

Stimulation of P2RX7 with extracellular ATP potentiates numerous LPS-induced proinflammatory events, including cytokine induction in macrophages, but the molecular mechanisms underlying this process are not well defined. Although P2RX7 ligation has been proposed to activate several transcription factors, many of the LPS-induced mediators affected by P2RX7 activation are not induced by P2RX7 agonists alone, suggesting a complementary role for P2RX7 in transcriptional regulation. Type I IFN production, whose expression is tightly controlled by multiple transcription factors that form an enhanceosome, is critical for resistance against LPS-containing bacteria. The effect of purinergic receptor signaling on LPS-dependent type I IFN is unknown and would be of great relevance to a diverse array of inflammatory conditions. The present study demonstrates that stimulation of macrophages with P2RX7 agonists substantially enhances LPS-induced IFN-? expression, and this enhancement is ablated in macrophages that do not express functional P2RX7 or when the MAPK MEK1/2 pathways are inhibited. Potentiation of LPS-induced IFN-? expression following P2RX7 stimulation is likely transcriptionally regulated, as this enhancement is observed at the IFN-? promoter level. Furthermore, P2RX7 stimulation is able to increase the phosphorylation and subsequent IFN-? promoter occupancy of IRF-3, a transcription factor that is critical for IFN-? transcription by TLR agonists. This newly discovered role for P2RX7 in IFN regulation may have implications in antimicrobial defense, which has been linked to P2RX7 activation in other studies. PMID:23911869

Gavala, M. L.; Liu, Y.-P.; Lenertz, L. Y.; Zeng, L.; Blanchette, J. B.; Guadarrama, A. G.; Denlinger, L. C.; Bertics, P. J.; Smith, J. A.

2013-01-01

25

Neuraminidase reprograms lung tissue and potentiates LPS-induced acute lung injury in mice  

PubMed Central

We previously reported that removal of sialyl residues primed PBMCs to respond to bacterial LPS stimulation in vitro. Therefore, we speculated that prior desialylation can sensitize the host to generate an enhanced inflammatory response upon exposure to a TLR ligand, such as LPS, in a murine model of acute lung injury. Intratracheal instillation of neuraminidase (NA) 30 min prior to intratracheal administration of LPS increased PMNs in the bronchoalveolar lavage fluid (BALF) and the wet-to-dry lung weight ratio, a measure of pulmonary edema, compared to mice that received LPS alone. Administration of NA alone resulted in desialylation of bronchiolar and alveolar surfaces and induction of TNF-?, IL-1?, and chemokines in lung homogenates and BALF; however, PMN recruitment in mice treated with NA alone did not differ from those of PBS-administered controls. NA pretreatment alone induced apoptosis and markedly enhanced LPS-induced endothelial apoptosis. Administration of recombinant Bcl-2, an anti-apoptotic molecule, abolished the effect of NA treatment on LPS-induced PMN recruitment and pulmonary edema formation. We conclude that NA pretreatment potentiates LPS-induced lung injury through enhanced PMN recruitment, pulmonary edema formation, and endothelial and myeloid cell apoptosis. A similar “reprogramming” of immune responses with desialylation may occur during respiratory infection with NA-expressing microbes and contribute to severe lung injury. PMID:24068662

Feng, Chiguang; Zhang, Lei; Nguyen, Chinh; Vogel, Stefanie N.; Goldblum, Simeon E.; Blackwelder, William C.; Cross, Alan S.

2013-01-01

26

Phosphoinositide-3 kinase ? required for LPS-induced transepithelial neutrophil trafficking in the lung  

PubMed Central

Phosphoinositide 3-kinase ? (PI3K?) is a critical mediator of directional cell movement. Here, we sought to characterize the role of PI3K? in mediating the different steps of PMN trafficking in the lung. In a murine model of LPS-induced lung injury, PMN migration into the different lung compartments was determined in PI3K? gene-deficient (PI3K??/?) and wildtype mice. Bone marrow chimeras were created to characterize the role of PI3K? on hematopoietic vs. non-hematopoietic cells. A small molecule PI3K? inhibitor was tested in vitro and in vivo. PMN adhesion to the pulmonary endothelium and transendothelial migration into the lung interstitium was enhanced in PI3K??/? mice. However, transepithelial migration into the alveolar space was reduced in these mice. When irradiated PI3K??/? mice were reconstituted with bone marrow from wildtype mice, migratory activity into the alveolar space was restored partially. A small molecule PI3K? inhibitor reduced chemokine-induced PMN migration in vitro when PMNs or epithelial cells but not when endothelial cells were treated. The inhibitor also reduced LPS-induced PMN migration in vivo. We conclude that PI3K? is required for transepithelial but not for transendothelial migration in LPS-induced lung injury. Inhibition of PI3K? activity may be effective at curbing excessive PMN infiltration in lung injury. PMID:19797129

Reutershan, Jorg; Saprito, Mary S.; Wu, Dan; Ruckle, Thomas; Ley, Klaus

2009-01-01

27

Ketamine inhibits LPS-induced calcium elevation and NF-kappa B activation in monocytes  

Microsoft Academic Search

Objective:To investigate whether ketamine could inhibit lipopolysaccharide (LPS)-induced intracellular calcium elevation and NF-kappa B activation in monocytes. Materials and methods:Isolated rat monocytes were challenged with 10 ?g\\/ml LPS with or without the presence of various concentrations of ketamine (10, 100, 1000 ?M). Intracellular calcium was monitored by laser confocal microscopy. NF-kappa B activity of the nuclear extracts of monocytes was

J. Sun; Z. Q. Zhou; R. Lv; W. Y. Li; J. G. Xu

2004-01-01

28

Tim-3 Negatively Mediates Natural Killer Cell Function in LPS-Induced Endotoxic Shock  

PubMed Central

Sepsis is an exaggerated inflammatory condition response to different microorganisms with high mortality rates and extremely poor prognosis. Natural killer (NK) cells have been reported to be the major producers of IFN-? and key players in promoting systematic inflammation in lipopolysaccharide (LPS)-induced endotoxic shock. T-cell immunoglobulin and mucin domain (Tim)-3 pathway has been demonstrated to play an important role in the process of sepsis, however, the effect of Tim-3 on NK cell function remains largely unknown. In this study, we observed a dynamic inverse correlation between Tim-3 expression and IFN-? production in NK cells from LPS-induced septic mice. Blockade of the Tim-3 pathway could increase IFN-? production and decrease apoptosis of NK cells in vitro, but had no effect on the expression of CD107a. Furthermore, NK cell cytotoxicity against K562 target cells was enhanced after blocking Tim-3 pathway. In conclusion, our results suggest that Tim-3 pathway plays an inhibitory role in NK cell function, which might be a potential target in modulating the excessive inflammatory response of LPS-induced endotoxic shock. PMID:25337993

Hou, Hongyan; Liu, Weiyong; Wu, Shiji; Lu, Yanjun; Peng, Jing; Zhu, Yaowu; Lu, Yanfang; Wang, Feng; Sun, Ziyong

2014-01-01

29

Wedelolactone inhibits LPS-induced pro-inflammation via NF-kappaB Pathway in RAW 264.7 cells  

PubMed Central

Background Wedelolactone (WEL), a major coumestan ingredient in Wedelia chinensis, has been used to treat septic shock, hepatitis and venom poisoning in traditional Chinese medicines. The objective of the study was to elucidate the anti-inflammatory effects and mechanism of WEL with a cellular model of lipopolysaccharide (LPS)-induced RAW 264.7 cells. Results To study the role of WEL in pro-inflammation, we measured key inflammation mediators and end products including nitric oxide (NO), prostaglandin E2 (PGE2), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and tumor necrosis factor-? (TNF-?) by using the Griess method, enzyme linked immunosorbent assay (ELISA) and Western blotting. Nuclear factor-kappaB (NF-?B) transcription activity was detected by luciferase reporter assay. The important pro-inflammatory transcription factors, NF-?B p65 and inhibitory kappaB alpha (I?B-?); and mitogen-activated protein kinases (MAPKs), including extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and p38 MAPK (p38) were analyzed by Western blotting. Our study showed that WEL (0.1, 1, 10 ?M) significantly inhibited the protein expression levels of iNOS and COX-2 in LPS-stimulated cells, as well as the downstream products, including NO, PGE2 and TNF-?. Moreover, WEL also inhibited LPS-induced NF-?B p65 activation via the degradation and phosphorylation of I?B-? and subsequent translocation of the NF-?B p65 subunit to the nucleus. Conclusions Our results revealed that WEL has a potential to be a novel anti-inflammatory agent targeting on the NF-?B signaling pathway. PMID:24176090

2013-01-01

30

Antipyretic effect of central [Pyr1]apelin13 on LPS-induced fever in the rat.  

PubMed

Intracerebroventricular (i.c.v.) injections of apelins have been shown to modulate the central control of cardiovascular function, as well as the homeostasis of fluid and salt balance, and to some extent also body core temperature. Here, we investigated the effects of i.c.v. administration of [Pyr(1)]apelin13 (PyrAp13; 20nmol) dissolved in artificial cerebrospinal fluid (aCSF), as compared to aCSF alone, on fever and sickness behavior elicited in rats by intraperitoneal injection of bacterial lipopolysaccharide (LPS, 100 ?g/kg). Injections of LPS induced a short phase of hypothermia followed by a biphasic fever, depression of motor activity, anorexia and adipsia. I.c.v. injections of PyrAp13 without systemic LPS application slightly augmented motor activity at statistically unaltered core temperature. In combination with LPS, central administration of PyrAp13 significantly reduced fever during the time period of 3-9h after injection, but did not significantly attenuate anorexia and adipsia, and had no effect on LPS-induced lethargy. Rats injected with PyrAp13 along with LPS showed a reduced level of LPS-induced circulating tumor necrosis factor-? (TNF-?). Primary neuroglial cultures established from the hypothalamic paraventricular nucleus (PVN) and the median preoptic nucleus (MnPO), brain sites being of major importance for central thermoregulation and also expressing the apelin receptor, were incubated with medium alone, medium containing LPS (100 ?g/ml) or LPS plus PyrAp13 (10(-6) mol/L). Ninety minutes after start of the incubation, LPS alone but not LPS in combination with PyrAp13 (10(-6) mol/L) caused a significant elevation of TNF-? in the supernatants. The novel observation that PyrAp13 represents a centrally acting endogenous antipyretic peptide is discussed in relation to its capacity to modulate peripheral and central formation of TNF-?. PMID:23500835

Hatzelmann, Thomas; Harden, Lois M; Roth, Joachim; Gerstberger, Rüdiger

2013-06-10

31

Hemopexin down-regulates LPS-induced proinflammatory cytokines from macrophages  

PubMed Central

Detection of LPS in tissues is an integral component of innate immunity that acts to protect against invasion by Gram-negative bacteria. Plasma down-regulates LPS-induced cytokine production from macrophages, thereby limiting systemic inflammation in blood and distant tissues. To identify the protein(s) involved in this process, we used classical biochemical chromatographic techniques to identify fractions of mouse sera that suppress LPS-induced TNF from bone marrow-derived macrophages (BMDMs). Fractionation yielded microgram quantities of a protein that was identified by MS to be hemopexin (Hx). Mouse Hx purified on hemin-agarose beads and rhHx decreased the production of cytokines from BMDMs and peritoneal macrophages induced by LPS. Preincubation of LPS with Hx did not affect the activity of LPS on LAL, whereas preincubation of Hx with macrophages followed by washing resulted in decreased activity of these cells in response to LPS, suggesting that Hx acts on macrophages rather than LPS. Heme-free Hx did not stimulate HO-1 in the macrophages. Purified Hx also decreased TNF and IL-6 from macrophages induced by the synthetic TLR2 agonist Pam3Cys. Our data suggest that Hx, which is an acute-phase protein that increases during inflammation, limits TLR4 and TLR2 agonist-induced macrophage cytokine production directly through a mechanism distinct from HO-1. PMID:19395472

Liang, Xueya; Lin, Tian; Sun, Guangjie; Beasley-Topliffe, Laura; Cavaillon, Jean-Marc; Warren, H. Shaw

2009-01-01

32

Manganese potentiates LPS-induced heme-oxygenase 1 in microglia but not dopaminergic cells: role in controlling microglial hydrogen peroxide and inflammatory cytokine output.  

PubMed

Excessive manganese (Mn) exposure increases output of glial-derived inflammatory products, which may indirectly contribute to the neurotoxic effects of this essential metal. In microglia, Mn increases hydrogen peroxide (H(2)O(2)) release and potentiates lipopolysaccharide (LPS)-induced cytokines (TNF-?, IL-6) and nitric oxide (NO). Inducible heme-oxygenase (HO-1) plays a role in the regulation of inflammation and its expression is upregulated in response to oxidative stressors, including metals and LPS. Because Mn can oxidatively affect neurons both directly and indirectly, we investigated the effect of Mn exposure on the induction of HO-1 in resting and LPS-activated microglia (N9) and dopaminergic neurons (N27). In microglia, 24h exposure to Mn (up to 250 ?M) had minimal effects on its own, but it markedly potentiated LPS (100 ng/ml)-induced HO-1 protein and mRNA. Inhibition of microglial HO-1 activity with two different inhibitors indicated that HO-1 is a positive regulator of the Mn-potentiated cytokine output and a negative regulator of the Mn-induced H(2)O(2) output. Mn enhancement of LPS-induced HO-1 does not appear to be dependent on H(2)O(2) or NO, as Mn+LPS-induced H(2)O(2) release was not greater than the increase induced by Mn alone and inhibition of iNOS did not change Mn potentiation of HO-1. However, because Mn exposure potentiated the LPS-induced nuclear expression of small Maf proteins, this may be one mechanism Mn uses to affect the expression of HO-1 in activated microglia. Finally, the potentiating effects of Mn on HO-1 appear to be glia-specific for Mn, LPS, or Mn+LPS did not induce HO-1 in N27 neuronal cells. PMID:21963524

Dodd, Celia A; Filipov, Nikolay M

2011-12-01

33

Manganese Potentiates LPS-Induced Heme-Oxygenase 1 in Microglia but not Dopaminergic Cells: Role in Controlling Microglial Hydrogen Peroxide and Inflammatory Cytokine Output  

PubMed Central

Excessive manganese (Mn) exposure increases output of glial-derived inflammatory products, which may indirectly contribute to the neurotoxic effects of this essential metal. In microglia, Mn increases hydrogen peroxide (H2O2) release and potentiates lipopolysaccharide (LPS)-induced cytokines (TNF-?, IL-6) and nitric oxide (NO). Inducible heme-oxygenase (HO-1) plays a role in the regulation of inflammation and its expression is upregulated in response to oxidative stressors, including metals and LPS. Because Mn can oxidatively affect neurons both directly and indirectly, we investigated the effect of Mn exposure on the induction of HO-1 in resting and LPS-activated microglia (N9) and dopaminergic neurons (N27). In microglia, 24 h exposure to Mn (up to 250 ?M) had minimal effects on its own, but it markedly potentiated LPS (100 ng/ml)-induced HO-1protein and mRNA. Inhibition of microglial HO-1 activity with two different inhibitors indicated that HO-1 is a positive regulator of the Mn-potentiated cytokine output and a negative regulator of the Mn-induced H2O2 output. Mn enhancement of LPS-induced HO-1 does not appear to be dependent on H2O2 or NO, as Mn+LPS-induced H2O2 release was not greater than the increase induced by Mn alone and inhibition of iNOS did not change Mn potentiation of HO-1. However, because Mn exposure potentiated the LPS-induced nuclear expression of small Maf proteins, this may be one mechanism Mn uses to affect the expression of HO-1 in activated microglia. Finally, the potentiating effects of Mn on HO-1 appear to be glia-specific for Mn, LPS, or Mn+LPS did not induce HO-1 in N27 neuronal cells. PMID:21963524

Dodd, Celia A.; Filipov, Nikolay M.

2012-01-01

34

Carnosic acid, a pro-electrophilic compound, inhibits LPS-induced activation of microglia.  

PubMed

In the previous studies, we reported that carnosic acid (CA) protects cortical neurons by activating the Keap1/Nrf2 pathway, which activation is initiated by S-alkylation of the critical cysteine thiol of the Keap1 protein by the "electrophilic"quinone-type CA. Here, we found that the pro-electrophilic CA inhibited the in vitro lipopolysaccharide (LPS)-induced activation of cells of the mouse microglial cell line MG6. LPS induced the expression of IL-1? and IL-6, typical inflammatory cytokines released from microglial cells. CA inhibited the NO production associated with a decrease in the level of inducible NO synthase. Neither CA nor LPS affected cell survival at the concentrations used here. These actions of CA seemed to be mediated by induction of phase 2 genes (gclc, gclm, nqo1 and xct). We propose that an inducer of phase 2 genes may be a critical regulator of microglial activation. Thus, CA is a unique pro-electrophilic compound that provides both a protective effect on neurons and an anti-inflammatory one on microglia through induction of phase 2 genes. PMID:22214931

Yanagitai, Mika; Itoh, Sayaka; Kitagawa, Tomomi; Takenouchi, Takato; Kitani, Hiroshi; Satoh, Takumi

2012-02-01

35

Iloprost improves endothelial barrier function in LPS-induced lung injury  

PubMed Central

RATIONALE Protective effects of prostacyclin and its stable analog Iloprost are mediated by elevation of intracellular cAMP leading to enhancement of peripheral actin cytoskeleton and cell-cell adhesive structures. This study tested hypothesis that iloprost may exhibit protective effects against lung injury and endothelial barrier dysfunction induced by bacterial wall lypopolysacharide (LPS). METHODS Endothelial barrier dysfunction was assessed by measurements of transendothelial permeability, morphologically, and analysis of LPS-activated inflammatory signaling. In vivo, C57BL/6J mice were challenged with LPS with or without iloprost or 8-bromoadenosine-3?,5?-cyclic monophosphate (Br-cAMP) treatment. Lung injury was monitored by measurements of bronchoalveolar lavage protein content, cell count, and Evans blue extravasation. RESULTS Iloprost and Br-cAMP attenuated disruption of endothelial monolayer and suppressed activation of p38 mitogen activated protein (MAP) kinase, NF?B pathway, Rho signaling, ICAM1 expression, and neutrophil migration after LPS challenge. In vivo, iloprost was effective against LPS-induced protein and neutrophil accumulation in bronchoalveolar lavage fluid and reduced myeloperoxidase activation, ICAM-1 expression, and Evans blue extravasation in the lungs. Inhibition of Rac activity abolished barrier protective and anti-inflammatory effects of iloprost and Br-cAMP. CONCLUSION Iloprost-induced elevation of intracellular cAMP triggers Rac signaling, which attenuates LPS-induced NF?B and p38 MAPK inflammatory pathways and Rho-dependent mechanism of endothelial permeability. PMID:22790920

Birukova, Anna A.; Wu, Tinghuai; Tian, Yufeng; Meliton, Angelo; Sarich, Nicolene; Tian, Xinyong; Leff, Alan; Birukov, Konstantin G.

2013-01-01

36

Cannabidiol (CBD) Enhances Lipopolysaccharide (LPS)-Induced Pulmonary Inflammation in C57BL/6 Mice  

PubMed Central

Cannabidiol (CBD) is a plant-derived cannabinoid that has been predominantly characterized as anti-inflammatory. However, it is clear that immune effects of cannabinoids can vary with cannabinoid concentration, or type or magnitude of immune stimulus. The present studies demonstrate that oral administration of CBD enhanced lipopolysaccharide (LPS)-induced pulmonary inflammation in C57BL/6 mice. The enhanced inflammatory cell infiltrate as observed in bronchoalveolar lavage fluid (BALF) was comprised mainly of neutrophils, with some monocytes. Concomitantly, CBD enhanced pro-inflammatory cytokine mRNA production, including tumor necrosis factor-? (Tnfa), interleukins (IL) 6 and 23 (Il6, Il23), and granulocyte colony stimulating factor (Gcsf). These results demonstrate that the CBD-mediated enhancement of LPS-induced pulmonary inflammation is mediated at the level of transcription of a variety of pro-inflammatory genes. The significance of these studies is that CBD is part of a therapeutic currently in use for spasticity and pain in multiple sclerosis patients, and therefore it is important to further understand mechanisms by which CBD alters immune function. PMID:23173851

Karmaus, Peer W. F.; Wagner, James G.; Harkema, Jack R.; Kaminski, Norbert E.; Kaplan, Barbara L.F.

2012-01-01

37

3,4,5-Trihydroxycinnamic Acid Inhibits LPS-Induced iNOS Expression by Suppressing NF-?B Activation in BV2 Microglial Cells  

PubMed Central

Although various derivatives of caffeic acid have been reported to possess a wide variety of biological activities such as neuronal protection against excitotoxicity and anti-inflammatory property, the biological activity of 3,4,5-trihydroxycinnamic acid (THC), a derivative of hydroxycinnamic acids, has not been clearly examined. The objective of the present study is to evaluate the anti-inflammatory effects of THC on lipopolysaccharide (LPS)-stimulated BV2 microglial cells. THC significantly suppressed LPS-induced excessive production of nitric oxide (NO) and expression of iNOS, which is responsible for the production of iNOS. THC also suppressed LPS-induced overproduction of pro-inflammatory cytokines such as IL-1? and TNF-? in BV2 microgilal cells. Furthermore, THC significantly suppressed LPS-induced degradation of I?B, which retains NF-?B in the cytoplasm. Therefore, THC attenuated nuclear translocation of NF-?B, a major pro-inflammatory transcription factor. Taken together, the present study for the first time demonstrates that THC exhibits anti-inflammatory activity through the suppression of NF-?B transcriptional activation in LPS-stimulated BV2 microglial cells. PMID:22563255

Lee, Jae-Won; Bae, Chang Jun; Choi, Yong-Jun; Kim, Song-In; Kim, Nam-Ho; Lee, Hee Jae; Kim, Sung-Soo; Kwon, Yong-Soo

2012-01-01

38

Yohimbine Promotes Cardiac NE Release and Prevents LPS-Induced Cardiac Dysfunction via Blockade of Presynaptic ?2A-Adrenergic Receptor  

PubMed Central

Myocardial depression is an important contributor to mortality in sepsis. We have recently demonstrated that ?2-adrenoceptor (AR) antagonist, yohimbine (YHB), attenuates lipopolysaccharide (LPS)-induced myocardial depression. However, the mechanisms for this action of YHB are unclear. Here, we demonstrated that YHB decreased nitric oxide (NO) and tumor necrosis factor-alpha (TNF-?) levels in the myocardium and plasma, attenuated cardiac and hepatic dysfunction, but not kidney and lung injuries in endotoxemic mice. Immunohistochemical analysis revealed that cardiac ?2A-AR was mostly located in sympathetic nerve presynaptic membrane; YHB decreased cardiac ?2A-AR level and promoted cardiac norepinephrine (NE) release in endotoxemic mice. Reserpine that exhausted cardiac NE without markedly decreasing plasma NE level abrogated the inhibitory effects of YHB on cardiac TNF-? and iNOS expression as well as cardiac dysfunction, but not the suppressive effects of YHB on plasma TNF-? and NO elevation in LPS-challenged mice. Furthermore, both reserpine and YHB significantly inhibited LPS-induced myocardial apoptosis. ?1-AR, ?2-AR, but not ?1-AR antagonists reversed the inhibitory effect of YHB on LPS-stimulated myocardial apoptosis. However, ?1-AR antagonist attenuated LPS-caused cardiomyocyte apoptosis, partly abolished the protective effect of YHB on the left ventricular ejection fraction in endotoxemic mice. Altogether, these findings indicate that YHB attenuates LPS-induced cardiac dysfunction, at least in part, through blocking presynaptic ?2A-AR and thus increasing cardiac NE release. YHB-elevated cardiac NE improves cardiac function via suppressing cardiac iNOS and TNF-? expression, activating ?1-AR and inhibiting cardiomyocyte apoptosis through ?1- and ?2-AR in endotoxemic mice. However, cardiac ?1-AR activation promotes LPS-induced cardiomyocyte apoptosis. PMID:23691077

Wang, Yiyang; Yu, Xiaohui; Wang, Faqiang; Wang, Yuan; Wang, Yanping; Li, Hongmei; Lv, Xiuxiu; Lu, Daxiang; Wang, Huadong

2013-01-01

39

Transiently enhanced LPS-induced fever following hyperthermic stress in rabbits  

NASA Astrophysics Data System (ADS)

Hyperthermia has been shown to induce an enhanced febrile response to the bacterial-derived endotoxin lipopolysaccharide (LPS). The aim of the present study was to test the hypothesis that the enhanced LPS-induced fever seen in heat stressed (HS) animals is caused by leakage of intestinal bacterial LPS into the circulation. Male rabbits were rendered transiently hyperthermic (a maximum rectal temperature of 43°C) and divided into three groups. They were then allowed to recover in a room at 24°C for 1, 2 or 3 days post-HS. One day after injection with LPS, the post-HS rabbits exhibited significantly higher fevers than the controls, though this was not seen in rabbits at either 2 or 3 days post-HS. The plasma levels of endogenous LPS were significantly increased during the HS as compared to those seen in normothermic rabbits prior to HS. LPS fevers were not induced in these animals. One day post-HS, rabbits that had been pretreated with oral antibiotics exhibited significantly attenuated LPS levels. When challenged with human recombinant interleukin-1? instead of LPS, the 1-day post-HS rabbits did not respond with enhanced fevers. The plasma levels of TNF? increased similarly during LPS-induced fevers in both the control and 1-day post-HS rabbits, while the plasma levels of corticosterone and the osmolality of the 1-day post-HS rabbits showed no significant differences to those seen prior to the HS. These results suggest that the enhanced fever in the 1-day post-HS rabbits is LPS specific, and may be caused by increased leakage of intestinal endotoxin into blood circulation.

Shibata, Masaaki; Uno, Tadashi; Riedel, Walter; Nishimaki, Michiyo; Watanabe, Kaori

2005-11-01

40

Stabilization of Nrf2 by tBHQ prevents LPS-induced apoptosis in differentiated PC12 cells  

Microsoft Academic Search

The inflammatory reaction plays an important role in the pathogenesis of the neurodegenerative disorders. tert-butylhydroquinone\\u000a (tBHQ) exhibits a wide range of pharmacological activities including anti-oxidative and anti-inflammatory action. In this\\u000a study, we tried to elucidate possible effects of tBHQ on lipopolysaccharide (LPS)-induced inflammatory reaction and its underlying\\u000a mechanism in neuron-like PC12 cells. tBHQ inhibited LPS-induced generation of reactive oxygen species

Fariba Khodagholi; Solaleh Khoramian Tusi

2011-01-01

41

Plasminogen Activator Inhibitor-1 Regulates LPS Induced Inflammation in Rat Macrophages through Autophagy Activation  

PubMed Central

Background. The mechanisms by which plasminogen activator inhibitor-1 (PAI-1) regulates inflammation, especially in acute respiratory distress syndrome (ARDS), are largely unknown. Objective. To assess the relationship between PAI-1 and autophagy in inflammatory reactions induced by LPS in rat NR8383 cells. Methods. ELISA was used to assess the amounts of TNF-?, IL-1?, and PAI-1 in cell culture supernatants; TLR4, MyD88, PAI-1, LC3, Beclin1, and mTOR protein and mRNA levels were determined by western blot and quantitative RT-PCR, respectively; western blot was used to determine NF-?B protein levels. To further evaluate the role of PAI-1, the PAI-1 gene was downregulated and overexpressed using the siRNA transfection technology and the pCDH-PAI-1, respectively. Finally, the GFP Positive Expression Rate Method was used to determine the rate of GFP-LC3 positive NR8383 cells. Results. In LPS-induced NR8383 cells, TNF-?, IL-1?, and PAI-1 expression levels increased remarkably. Upon PAI-1 knockdown, TNF-?, IL-1?, PAI-1, TLR4, MyD88, NF-?B, LC3, and Beclin1 levels were decreased, while mTOR increased. Conversely, overexpression of PAI-1 resulted in increased amounts of TNF-?, IL-1?, PAI-1, TLR4, MyD88, NF-?B, LC3, and Beclin1. However, no significant change was observed in mTOR expression. Conclusions. In NR8383 cells, PAI-1 contributes in the regulation of LPS-induced inflammation, likely by promoting autophagy. PMID:25133205

Wang, Zhong-Hui; Ren, Wei-Ying; Zhu, Lei; Hu, Li-Juan

2014-01-01

42

Andrographolide Protects against LPS-Induced Acute Lung Injury by Inactivation of NF-?B  

PubMed Central

Background Nuclear factor-?B (NF-?B) is a central transcriptional factor and a pleiotropic regulator of many genes involved in acute lung injury. Andrographolide is found in the plant of Andrographis paniculata and widely used in Traditional Chinese Medicine, exhibiting potently anti-inflammatory property by inhibiting NF-?B activity. The purpose of our investigation was designed to reveal the effect of andrographolide on various aspects of LPS induced inflammation in vivo and in vitro. Methods and Results In vivo, BALB/C mice were subjected to LPS injection with or without andrographolide treatments to induce ALI model. In vitro, MLE-12 cells were stimulated with LPS in the presence and absence of andrographolide. In vivo, pulmonary inflammation, pulmonary edema, ultrastructure changes of type II alveolar epithelial cells, MPO activity, total cells, neutrophils, macrophages, TNF-?, IL-6 and IL-1? in BALF, along with the expression of VCAM-1 and VEGF were dose-dependently attenuated by andrographolide. Meanwhile, in vitro, the expression of VCAM-1 and VEGF was also reduced by andrographolide. Moreover, our data showed that andrographolide significantly inhibited the ratios of phospho-IKK?/total IKK?, phospho-I?B?/total I?B? and phospho-NF-?B p65/total NF-?B p65, and NF-?B p65 DNA binding activities, both in vivo and in vitro. Conclusions These results indicate that andrographolide dose-dependently suppressed the severity of LPS-induced ALI, more likely by virtue of andrographolide-mediated NF-?B inhibition at the level of IKK? activation. These results suggest andrographolide may be considered as an effective and safe drug for the potential treatment of ALI. PMID:23437127

Zhu, Tao; Wang, Dao-xin; Zhang, Wei; Liao, Xiu-qing; Guan, Xian; Bo, Hong; Sun, Jia-yang; Huang, Ni-wen; He, Jing; Zhang, Yun-kun; Tong, Jing; Li, Chang-yi

2013-01-01

43

Hydroxyethyl starch normalizes platelet and leukocyte adhesion within pulmonary microcirculation during LPS-induced endotoxemia.  

PubMed

Growing evidence supports substantial pathophysiological impact of platelets and their interactions on the development of septic lung failure. We developed a rat model of endotoxemia for direct in situ visualization of pulmonary microcirculation by in vivo fluorescence videomicroscopy. Male Sprague-Dawley rats were assigned to control, endotoxemia (Escherichia coli LPS, 15 mg/kg, i.v.), and fluid management for treatment of LPS-induced hypovolemia (Ringer lactate, hydroxyethyl starch [HES] 6%) groups (n = 7 each). Leukocytes were labeled in vivo by rhodamine, and 5 x 10(6) Calcein-AM-labeled nonactivated platelets were injected. Microcirculatory parameters (vessel diameter, ventilation-perfusion ratio) and adhesive characteristics of platelets and leukocytes (velocity, rolling, sticking) within the pulmonary microcirculation were quantified after endotoxin application under various regimens of fluid substitution for 60 min. A reduction of cell velocity and enhanced cell adhesion was seen in leukocytes and platelets (P < 0.05) after LPS injection. Fluid treatment with HES 6% resulted in a significant increase of platelet's velocity compared with the LPS group (442.86 +/- 20.60 vs. 343.93 +/- 11.17; P < 0.05), whereas Ringer lactate showed no beneficial effects. Similarly, HES 6% normalized LPS-induced platelet rolling and sticking as well as alterations in ventilation-perfusion ratio. Using direct visualization of the pulmonary microcirculation, we observed that platelet and leukocyte interactions are enhanced in the lung during LPS endotoxemia. Fluid therapy with HES 6% seems to have restorative effects on these cellular functions within the pulmonary microcirculation. PMID:17545948

Küpper, Sebastian; Mees, Soeren Torge; Gassmann, Peter; Brodde, Martin F; Kehrel, Beate; Haier, Joerg

2007-09-01

44

Tanshinone IIA protects rabbits against LPS-induced disseminated intravascular coagulation (DIC)  

PubMed Central

Aim: To evaluate the effects of tanshinone IIA (Tan IIA), a lipophilic diterpene from the Chinese herb Salvia miltiorrhiza, on lipopolysaccharide (LPS)-induced disseminated intravascular coagulation (DIC) in rabbits. Methods: LPS-induced DIC model was made in adult male New Zealand rabbits by continuous intravenous infusion of LPS (0.5 mg/kg) via marginal ear vein for 6 h. The animals were simultaneously administered with Tan IIA (1, 3 and 10 mg/kg) or heparin (500 000 IU/kg) through continuous infusion via the contralateral marginal ear vein for 6 h. Before and 2 and 6 h after the start of LPS infusion, blood samples were taken for biochemical analyses. Results: Continuous infusion of LPS into the rabbits gradually impaired the hemostatic parameters, damaged renal and liver functions, increased the plasma TNF-? level, and led to a high mortality rate (80%). Treatment of the rabbits with Tan IIA dose-dependently attenuated the increase in activated partial thromboplastin time (APTT), prothrombin time (PT) and fibrin-fibrinogen degradation products (FDP); ameliorated the decrease in plasma levels of fibrinogen and platelets; and reversed the decline in activity of protein C and antithrombin III. Meanwhile, the treatment significantly suppressed the increase in the plasma levels of aminotransferase, creatinine and TNF-?, and led to much lower mortality (46.7% and 26.7% for the medium- and high-dose groups). Treatment of the rabbits with the high dose of heparin also effectively improved the hemostatic parameters, ameliorated liver and renal injuries, and reduced the plasma level of TNF-?, and significantly reduced the mortality (33.3%). Conclusion: Tan IIA exerts a protective effect against DIC in rabbits. PMID:22983394

Wu, Liang-cai; Lin, Xi; Sun, Hao

2012-01-01

45

IL-8 signaling does not mediate intra-amniotic LPS-induced inflammation and maturation in preterm fetal lamb lung  

PubMed Central

Preterm infants exposed to chorioamnionitis and preterm sheep fetuses exposed to intra-amniotic (IA) LPS have lung inflammation, increased IL-8 levels, and lung maturation. We tested the hypothesis that IL-8 signaling mediates IA LPS-induced lung inflammation and lung maturation. Two strategies were used: 1) we tested if IA injection of recombinant sheep IL-8 (rsIL-8) induced fetal inflammation and 2) if IL-8 signaling was blocked by a novel CXCR2 receptor blocker, nicotinanilide thioglycolate methyl ester (NTME). To test effects of IL-8 in the fetus, rsIL-8 was given intravascularly (50 ?g) at 124 ± 1 day of gestation (term = 150 days). A separate group of sheep was given IA rsIL-8 (100 ?g) and delivered 5 h to 7 days later at 124 ± 1 day of gestation. After confirming efficacy of the CXCR2 inhibitor, effects of IL-8 blockade were tested by injecting fetal sheep intramuscularly with NTME (10 mg) before IA injection of Escherichia coli LPS (10 mg). Sheep fetuses were delivered 1 or 7 days after injections at 124 ± 1 day of gestation. IA rsIL-8 induced a modest fivefold increase in bronchoalveolar lavage (BAL) monocytes and neutrophils and increased lung monocyte hydrogen peroxide generation. However, rsIL-8 did not induce lung maturation. Intravascular rsIL-8 did not change fetal cardiovascular variables, blood pH, or blood leukocyte counts. Inhibition of CXCR2 decreased IA LPS-induced increases in BAL proteins at 1 day but not at 7 days. NTME did not significantly decrease IA LPS-induced BAL leukocyte influx and lung cytokine mRNA expression. Inhibition of CXCR2 did not change IA LPS-induced lung maturation. IL-8 signaling does not mediate LPS-induced lung inflammation and lung maturation. PMID:19574422

Kallapur, Suhas G.; Moss, Timothy J. M.; Auten, Richard L.; Nitsos, Ilias; Pillow, J. Jane; Kramer, Boris W.; Maeda, Dean Y.; Newnham, John P.; Ikegami, Machiko; Jobe, Alan H.

2009-01-01

46

Genetic Deficiency of NADPH Oxidase Does Not Diminish but Rather Enhances LPS-Induced Acute Inflammatory Responses in Vivo  

PubMed Central

Reactive oxygen species (ROS) and oxidative stress are thought to play a central role in the etiology of cell dysfunction and tissue damage in sepsis. However, there is limited and controversial evidence from in vivo studies that ROS mediate cell signaling processes that elicit acute inflammatory responses during sepsis. Since NADPH oxidase is one of the main cellular sources of ROS, we investigated the role of this enzyme in lipopolysaccharide (LPS)-induced acute inflammation in vivo, utilizing mice deficient in the gp91phox or p47phox subunits of NADPH oxidase. Age and body-weight matched C57BL/6J wild-type (WT) and gp91phox?/? and p47phox?/? mice were injected i.p. with 50 µg LPS or saline vehicle, and sacrificed at different time points up to 24 hours. We found that LPS-induced acute inflammatory responses in serum and tissues were not significantly diminished in gp91phox?/? and p47phox?/? mice compared to WT mice. Rather, genetic deficiency of NADPH oxidase was associated with enhanced gene expression of inflammatory mediators and increased neutrophil recruitment to lung and heart. Furthermore, no protection from LPS-induced septic death was observed in either knockout strain. Our findings suggest that NADPH oxidase-mediated ROS production and cellular redox signaling do not promote but instead limit LPS-induced acute inflammatory responses in vivo. PMID:19124074

Zhang, Wei-Jian; Wei, Hao; Frei, Balz

2008-01-01

47

Leonurine ameliorates LPS-induced acute kidney injury via suppressing ROS-mediated NF-?B signaling pathway.  

PubMed

Acute kidney injury (AKI) is an abrupt loss of kidney function. Severe AKI requires renal replacement therapy and has high mortality. Leonurine (LEO), an alkaloid isolated from Leonurus cardiaca, has shown biological effects such as antioxidant, anticoagulant, and anti-apoptosis. We have examined the effect of LEO on lipopolysaccharide (LPS)-induced AKI in mice and further studied the mechanism involved. Blood urea nitrogen (BUN), creatinine and cytokine were estimated in the serum or tissue. Kidney tissue specimens were used for biochemical estimations of lipid peroxides (LPO), reduced glutathione (GSH), and reactive oxygen species (ROS). The effects of LEO on LPS-induced renal tissue damage were detected by hematoxylin and eosin (HE) stain and electron microscopy. The production of cytokines in the tissue and blood was measured by ELISA. Protein phosphorylation and protein subcellular localization were tested by Western blot. LEO is protected against LPS-induced AKI, improved animal survival and maintained the redox balance. The beneficial effects of LEO were accompanied by the down-regulation of TNF-?, IL-1, IL-6, IL-8, KIM-1 expression and by the inhibition of the phosphorylation of I?B? and p65 translocalization. These results suggest that LEO may suppress NF-?B activation and inhibit pro-inflammatory cytokine production via decreasing cellular ROS production. Accumulating studies have demonstrated that LEO reduces kidney injury and protects renal functions from LPS-induced kidney injury. PMID:24924288

Xu, Daliang; Chen, Maosheng; Ren, Xianzhi; Ren, Xianguo; Wu, Yonggui

2014-09-01

48

Catalpol protects dopaminergic neurons from LPS-induced neurotoxicity in mesencephalic neuron-glia cultures  

Microsoft Academic Search

Inflammation plays an important role in the pathogenesis of Parkinson's disease (PD). Microglia, the resident immune cells in the central nervous system, are pivotal in the inflammatory reaction. Activated microglia can induce expression of inducible nitric-oxide synthase (iNOS) and release significant amounts of nitric oxide (NO) and TNF-?, which can damage the dopaminergic neurons. Catalpol, an iridoid glycoside, contained richly

Yuan-Yuan Tian; Li-Jia An; Lan Jiang; Yan-Long Duan; Jun Chen; Bo Jiang

2006-01-01

49

Bcl10 mediates LPS-induced activation of NF-kappaB and IL-8 in human intestinal epithelial cells.  

PubMed

Lipopolysaccharide (LPS) is recognized as an inducer of the inflammatory response associated with gram-negative sepsis and systemic inflammatory response syndrome. LPS induction proceeds through Toll-like receptor (TLR) in immune cells and intestinal epithelial cells (IEC). This report presents the first identification of Bcl10 (B-cell CLL/lymphoma 10) as a mediator of the LPS-induced activation of IL-8 in human IEC. Bcl10 is a caspase-recruitment domain-containing protein, associated with constitutive activation of NF-kappaB in MALT (mucosa-associated lymphoid tissue) lymphomas. The normal human IEC line NCM460, normal primary human colonocytes, and ex vivo human colonic tissue were exposed to 10 ng/ml of LPS for 2-6 h. Effects on Bcl10, phospho-IkappaBalpha, NF-kappaB, and IL-8 were determined by Western blot, ELISA, immunohistochemistry, and confocal microscopy. Effects of Bcl10 silencing by small-interfering RNA (siRNA), TLR4 blocking antibody, TLR4 silencing by siRNA, and an IL-1 receptor-associated kinase (IRAK)-1/4 inhibitor on LPS-induced activation were examined. Following Bcl10 silencing, LPS-induced increases in NF-kappaB, IkappaBalpha, and IL-8 were significantly reduced (P < 0.001). Increasing concentrations of LPS were associated with higher concentrations of Bcl10 protein when quantified by ELISA, and the association between LPS exposure and increased Bcl10 was also demonstrated by Western blot, immunohistochemistry, and confocal microscopy. Exposure to TLR4 antibody, TLR4 siRNA, or an IRAK-1/4 inhibitor eliminated the LPS-induced increases in Bcl10, NF-kappaB, and IL-8. Identification of Bcl10 as a mediator of LPS-induced activation of NF-kappaB and IL-8 in normal human IEC provides new insight into mechanisms of epithelial inflammation and new opportunities for therapeutic intervention. PMID:17540779

Bhattacharyya, Sumit; Borthakur, Alip; Pant, Nitika; Dudeja, Pradeep K; Tobacman, Joanne K

2007-08-01

50

Contribution of the sympathetic hormone epinephrine to the sensitizing effect of ethanol on LPS-induced liver damage in mice  

PubMed Central

It is well known that ethanol preexposure sensitizes the liver to LPS hepatotoxicity. The mechanisms by which ethanol enhances LPS-induced liver injury are not completely elucidated but are known to involve an enhanced inflammatory response. Ethanol exposure also increases the metabolic rate of the liver, and this effect of ethanol on liver is mediated, at least in part, by the sympathetic hormone, epinephrine. However, whether or not the sympathetic nervous system also contributes to the sensitizing effect of ethanol preexposure on LPS-induced liver damage has not been determined. The purpose of this study was therefore to test the hypotheses that 1) epinephrine preexposure enhances LPS-induced liver damage (comparable to that of ethanol preexposure) and that 2) the sympathetic nervous system contributes to the sensitizing effect of ethanol. Accordingly, male C57BL/6J mice were administered epinephrine for 5 days (2 mg/kg per day) via osmotic pumps or bolus ethanol for 3 days (6 g/kg per day) by gavage. Twenty-four hours later, mice were injected with LPS (10 mg/kg ip). Both epinephrine and ethanol preexposure exacerbated LPS-induced liver damage and inflammation. Concomitant administration of propranolol with ethanol significantly attenuated the sensitizing effect of ethanol on LPS-induced liver damage. These data support the hypothesis that the sympathetic nervous system contributes, at least in part, to the mechanism of the sensitizing effect of ethanol. These results also suggest that sympathetic tone may contribute to the initiation and progression of alcoholic liver disease. PMID:18325983

Montfort, Claudia von; Beier, Juliane I.; Guo, Luping; Kaiser, J. Phillip; Arteel, Gavin E.

2009-01-01

51

Fingolimod affects gene expression profile associated with LPS-induced memory impairment.  

PubMed

Lipopolysaccharide is an endotoxin to induce sickness behavior in several animal models to explore the link between immune activation and cognition. Neuroinflammation playing a pivotal role in disease progress is evidently influenced by sphingosine-1-phosphate. As one of the sphingosine analogs in clinical use for multiple sclerosis, fingolimod (FTY720) was shown to substantially affect gene expression profile in the context of AD in our previous experiments. The present study was designed to evaluate the drug efficacy in the context of the mere inflammatory context leading to memory impairment. FTY720 was repeatedly administered for a few days before or after intracerebral lipopolysaccharide (LPS) injection in rats. Animal's brains were then assigned to histological as well as multiplex mRNA assay following memory performance test. Both FTY720 pre-treatment and post-treatment were similarly capable of ameliorating LPS-induced memory impairment as assessed by passive avoidance test. Such amending effects may be partly accountable by the concomitant alterations in transcriptional levels of mitogen-activated protein kinases as well as inflammatory genes determined by QuantiGene Plex analysis. These findings confirming FTY720 application benefits suggest its efficacy may not differ significantly while considered either as a preventive or as a therapeutic approach against neuroinflammation. PMID:25098558

Omidbakhsh, Rana; Rajabli, Banafshe; Nasoohi, Sanaz; Khallaghi, Behzad; Mohamed, Zahurin; Naidu, Murali; Ahmadiani, Abolhassan; Dargahi, Leila

2014-11-01

52

Protective Effects of Baicalin on Decidua Cells of LPS-Induced Mice Abortion  

PubMed Central

The study was carried out to investigate the protective effects of Baicalin on decidual cells of LPS-induced abortion mice. In the in vitro experiment, the decidual cells were cultured by uterus tissue mass cultivation sampled at day 6 of pregnancy, and gradient concentrations of LPS were used to determine the optimal LPS concentration of the injured decidual cells model. The injured decidual cells were treated with Baicalin (4??g/mL) to determine the protective role of Baicalin. In the in vivo experiment, lipopolysaccharide (LPS) was injected intravenously via the tail vein to induce abortion at day 6 of pregnancy, and the mice were given different concentrations of Baicalin by oral gavage consecutively at days 7 to 8 of pregnancy. On day 9 of gestation, the mice were sacrificed. The TNF and progesterone contents in the serum were assayed by ELISA. The results clearly revealed that Baicalin can prevent the injury to decidual cells from LPS dose dependently, TNF was decreased significantly (P < 0.01) compared to LPS group, and there was no effect on the progesterone. These findings suggest that Baicalin has protective effects on the injured decidual cells in the pregnant mice. PMID:25386564

Wang, Xiaodan; Zhao, Yantao; Zhong, Xiuhui

2014-01-01

53

p52-independent nuclear translocation of RelB promotes LPS-induced attachment  

SciTech Connect

The NF-{kappa}B signaling pathways have a critical role in the development and progression of various cancers. In this study, we demonstrated that the small cell lung cancer cell line (SCLC) H69 expressed a unique NF-{kappa}B profile as compared to other cancer cell lines. The p105/p50, p100/p52, c-Rel, and RelB protein and mRNA transcripts were absent in H69 cells but these cells expressed RelA/p65. The activation of H69 cells by lipopolysaccharide (LPS) resulted in the induction of RelB and p100 expression. The treatment also induced the nuclear translocation of RelB without the processing of p100 to p52. Furthermore, LPS-induced {beta}1 integrin expression and cellular attachment through an NF-{kappa}B-dependent mechanism. Blocking RelB expression prevented the increase in the expression of {beta}1 integrin and the attachment of H69. Taken together, the results suggest that RelB was responsible for the LPS-mediated attachment and may play an important role in the progression of some cancers.

Saito, T. [Laboratory of Immunology, National Institute on Aging, NIH Biomedical Research Center, Baltimore, MD 21224 (United States)] [Laboratory of Immunology, National Institute on Aging, NIH Biomedical Research Center, Baltimore, MD 21224 (United States); Sasaki, C.Y., E-mail: sasakic@grc.nia.nih.gov [Laboratory of Immunology, National Institute on Aging, NIH Biomedical Research Center, Baltimore, MD 21224 (United States); Rezanka, L.J.; Ghosh, P.; Longo, D.L. [Laboratory of Immunology, National Institute on Aging, NIH Biomedical Research Center, Baltimore, MD 21224 (United States)] [Laboratory of Immunology, National Institute on Aging, NIH Biomedical Research Center, Baltimore, MD 21224 (United States)

2010-01-01

54

Eukaryotic elongation factor 2 controls TNF-? translation in LPS-induced hepatitis.  

PubMed

Bacterial LPS (endotoxin) has been implicated in the pathogenesis of acute liver disease through its induction of the proinflammatory cytokine TNF-?. TNF-? is a key determinant of the outcome in a well-established mouse model of acute liver failure during septic shock. One possible mechanism for regulating TNF-? expression is through the control of protein elongation during translation, which would allow rapid cell adaptation to physiological changes. However, the regulation of translational elongation is poorly understood. We found that expression of p38?/? MAPK proteins is required for the elongation of nascent TNF-? protein in macrophages. The MKK3/6-p38?/? pathway mediated an inhibitory phosphorylation of eukaryotic elongation factor 2 (eEF2) kinase, which in turn promoted eEF2 activation (dephosphorylation) and subsequent TNF-? elongation. These results identify a new signaling pathway that regulates TNF-? production in LPS-induced liver damage and suggest potential cell-specific therapeutic targets for liver diseases in which TNF-? production is involved. PMID:23202732

González-Terán, Bárbara; Cortés, José R; Manieri, Elisa; Matesanz, Nuria; Verdugo, Ángeles; Rodríguez, María E; González-Rodríguez, Águeda; Valverde, Ángela M; Valverde, Ángela; Martín, Pilar; Davis, Roger J; Sabio, Guadalupe

2013-01-01

55

Exogenous rhTRX reduces lipid accumulation under LPS-induced inflammation  

PubMed Central

Redox-regulating molecule, recombinant human thioredoxin (rhTRX) which shows anti-inflammatory, and anti-oxidative effects against lipopolysaccharide (LPS)-stimulated inflammation and regulate protein expression levels. LPS-induced reactive oxygen intermediates (ROI) and NO production were inhibited by exogenous rhTRX. We identified up/downregulated intracellular proteins under the LPS-treated condition in exogenous rhTRX-treated A375 cells compared with non-LPS-treated cells via 2-DE proteomic analysis. Also, we quantitatively measured cytokines of in vivo mouse inflammation models using cytometry bead array. Exogenous rhTRX inhibited LPS-stimulated production of ROI and NO levels. TIP47 and ATP synthase may influence the inflammation-related lipid accumulation by affecting lipid metabolism. The modulation of skin redox environments during inflammation is most likely to prevent alterations in lipid metabolism through upregulation of TIP47 and ATP synthase and downregulation of inflammatory cytokines. Our results demonstrate that exogenous rhTRX has anti-inflammatory properties and intracellular regulatory activity in vivo and in vitro. Monitoring of LPS-stimulated pro-inflammatory conditions treated with rhTRX in A375 cells could be useful for diagnosis and follow-up of inflammation reduction related with candidate proteins. These results have a therapeutic role in skin inflammation therapy. PMID:24406320

Han, Gi-Yeon; Lee, Eun-Kyung; Park, Hey-won; Kim, Hyun-Jung; Kim, Chan-Wha

2014-01-01

56

3,4,5-Trihydroxycinnamic acid increases heme-oxygenase-1 (HO-1) and decreases macrophage infiltration in LPS-induced septic kidney.  

PubMed

We previously demonstrated that 3,4,5-trihydorxycinnamic acid (THC), a derivative of hydroxycinnamic acids, possesses protective effect in lipopolysaccharide (LPS)-induced endotoxemia models. However, the effects of THC in LPS-induced septic kidney are still unclear. Therefore, the present study was carried out to examine the effects of THC in LPS-challenged septic kidney using mesangial cell line and Balb/c mice. THC pretreatment effectively inhibited LPS-induced macrophage infiltration and the secretion of pro-inflammatory cytokines in the kidney of LPS-challenged animals. Pretreatment of rat mesangial cells with THC significantly attenuated LPS-induced PGE2 production and COX-2 expression. THC also significantly suppressed LPS-induced expression of MCP-1 in LPS-activated septic kidney and rat mesangial cells. In addition, THC significantly attenuated LPS-induced degradation of I?B-? in LPS-induced rat mesangial cells. THC also increased the expression of heme oxygenase-1 (HO-1) in LPS-challenged septic kidney and mesangial cells. Multiple signaling pathways including p38 and AKT have been observed to be involved in the THC-induced activation of HO-1 expression. The present data clearly demonstrate that THC protects LPS-challenged septic kidney by decreasing macrophage infiltration and increasing HO-1 expression, suggesting that THC might be a valuable therapeutic agent for compromised kidney in sepsis. PMID:25091807

Lee, Jae-Won; Kwon, Jae-Hyun; Lim, Man Sup; Lee, Hee Jae; Kim, Sung-Soo; Lim, So Young; Chun, Wanjoo

2014-12-01

57

Involvement of mitogen-activated protein kinases and NF{kappa}B in LPS-induced CD40 expression on human monocytic cells  

SciTech Connect

CD40 is a costimulatory molecule linking innate and adaptive immune responses to bacterial stimuli, as well as a critical regulator of functions of other costimulatory molecules. The mechanisms regulating lipopolysaccharide (LPS)-induced CD40 expression have not been adequately characterized in human monocytic cells. In this study we used a human monocytic cell line, THP-1, to investigate the possible mechanisms of CD40 expression following LPS exposure. Exposure to LPS resulted in a dose- and time-dependent increase in CD40 expression. Further studies using immunoblotting and pharmacological inhibitors revealed that mitogen-activated protein kinases (MAPKs) and NF{kappa}B were activated by LPS exposure and involved in LPS-induced CD40 expression. Activation of MAPKs was not responsible for LPS-induced NF{kappa}B activation. TLR4 was expressed on THP-1 cells and pretreatment of cells with a Toll-like receptor 4 (TLR4) neutralizing antibody (HTA125) significantly blunted LPS-induced MAPK and NF{kappa}B activation and ensuing CD40 expression. Additional studies with murine macrophages expressing wild type and mutated TLR4 showed that TLR4 was implicated in LPS-induced ERK and NF{kappa}B activation, and CD40 expression. Moreover, blockage of MAPK and NF{kappa}B activation inhibited LPS-induced TLR4 expression. In summary, LPS-induced CD40 expression in monocytic cells involves MAPKs and NF{kappa}B.

Wu Weidong [Center for Environmental Medicine, Asthma, and Lung Biology, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)]|[Department of Pediatrics, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)], E-mail: Weidong_Wu@med.unc.edu; Alexis, Neil E. [Center for Environmental Medicine, Asthma, and Lung Biology, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)]|[Department of Pediatrics, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Chen Xian [Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)]|[Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Bromberg, Philip A. [Center for Environmental Medicine, Asthma, and Lung Biology, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)]|[Department of Medicine, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Peden, David B. [Center for Environmental Medicine, Asthma, and Lung Biology, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)]|[Department of Pediatrics, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)]|[Department of Medicine, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)

2008-04-15

58

Inhibition of LPS-induced airway neutrophilic inflammation in healthy volunteers with an oral CXCR2 antagonist  

PubMed Central

Background Inhaled lipopolysaccharide (LPS) induces a dose-dependent, acute neutrophilic response in the airways of healthy volunteers that can be quantified in induced sputum. Chemokines, such as CXCL1 and CXCL8, play an important role in neutrophilic inflammation in the lung through the activation of CXCR2 and small molecule antagonists of these receptors have now been developed. We investigated the effect of AZD8309, a CXCR2 antagonist, compared with placebo on LPS-induced inflammation measured in sputum of healthy volunteers. Methods Twenty healthy subjects were randomized in a double-blind placebo-controlled, cross-over study. AZD8309 (300 mg) or placebo was dosed twice daily orally for 3 days prior to challenge with inhaled LPS and induced sputum was collected 6 h later. Results Treatment with AZD8309 showed a mean 77% reduction in total sputum cells (p?LPS-induced inflammation measured in induced sputum of normal volunteers, indicating that this treatment may be useful in the treatment of neutrophilic diseases of the airways, such as COPD, severe asthma and cystic fibrosis. Trial registration NCT00860821. PMID:24341382

2013-01-01

59

Progesterone Is Essential for Protecting against LPS-Induced Pregnancy Loss. LIF as a Potential Mediator of the Anti-inflammatory Effect of Progesterone  

PubMed Central

Lipopolysaccharide (LPS) administration to mice on day 7 of gestation led to 100% embryonic resorption after 24 h. In this model, nitric oxide is fundamental for the resorption process. Progesterone may be responsible, at least in part, for a Th2 switch in the feto-maternal interface, inducing active immune tolerance against fetal antigens. Th2 cells promote the development of T cells, producing leukemia inhibitory factor (LIF), which seems to be important due to its immunomodulatory action during early pregnancy. Our aim was to evaluate the involvement of progesterone in the mechanism of LPS-induced embryonic resorption, and whether LIF can mediate hormonal action. Using in vivo and in vitro models, we provide evidence that circulating progesterone is an important component of the process by which infection causes embryonic resorption in mice. Also, LIF seems to be a mediator of the progesterone effect under inflammatory conditions. We found that serum progesterone fell to very low levels after 24 h of LPS exposure. Moreover, progesterone supplementation prevented embryonic resorption and LPS-induced increase of uterine nitric oxide levels in vivo. Results show that LPS diminished the expression of the nuclear progesterone receptor in the uterus after 6 and 12 h of treatment. We investigated the expression of LIF in uterine tissue from pregnant mice and found that progesterone up-regulates LIF mRNA expression in vitro. We observed that LIF was able to modulate the levels of nitric oxide induced by LPS in vitro, suggesting that it could be a potential mediator of the inflammatory action of progesterone. Our observations support the view that progesterone plays a critical role in a successful pregnancy as an anti-inflammatory agent, and that it could have possible therapeutic applications in the prevention of early reproductive failure associated with inflammatory disorders. PMID:23409146

Aisemberg, Julieta; Vercelli, Claudia A.; Bariani, Maria V.; Billi, Silvia C.; Wolfson, Manuel L.; Franchi, Ana M.

2013-01-01

60

Activated protein C ameliorates LPS-induced acute kidney injury and downregulates renal INOS and angiotensin 2.  

PubMed

Endothelial dysfunction contributes significantly to acute renal failure (ARF) during inflammatory diseases including septic shock. Previous studies have shown that activated protein C (APC) exhibits anti-inflammatory properties and modulates endothelial function. Therefore, we investigated the effect of APC on ARF in a rat model of endotoxemia. Rats subjected to lipopolysaccharide (LPS) treatment exhibited ARF as illustrated by markedly reduced peritubular capillary flow and increased serum blood urea nitrogen (BUN) levels. Using quantitative two-photon intravital microscopy, we observed that at 3 h post-LPS treatment, rat APC (0.1 mg/kg iv bolus) significantly improved peritubular capillary flow [288 +/- 15 microm/s (LPS) vs. 734 +/- 59 microm/s (LPS+APC), P = 0.0009, n = 6], and reduced leukocyte adhesion (P = 0.003) and rolling (P = 0.01) compared with the LPS-treated group. Additional experiments demonstrated that APC treatment significantly improved renal blood flow and reduced serum BUN levels compared with 24-h post-LPS treatment. Biochemical analysis revealed that APC downregulated inducible nitric oxide synthase (iNOS) mRNA levels and NO by-products in the kidney. In addition, APC modulated the renin-angiotensin system by reducing mRNA expression levels of angiotensin-converting enzyme-1 (ACE1), angiotensinogen, and increasing ACE2 mRNA levels in the kidney. Furthermore, APC significantly reduced ANG II levels in the kidney compared with the LPS-treated group. Taken together, these data suggest that APC can suppress LPS-induced ARF by modulating factors involved in vascular inflammation, including downregulation of renal iNOS and ANG II systems. Furthermore, the data suggest a potential therapeutic role for APC in the treatment of ARF. PMID:17409278

Gupta, Akanksha; Rhodes, George J; Berg, David T; Gerlitz, Bruce; Molitoris, Bruce A; Grinnell, Brian W

2007-07-01

61

Myeloid depletion of SOCS3 enhances LPS-induced acute lung injury through CCAAT/enhancer binding protein ? pathway  

PubMed Central

Although uncontrolled inflammatory response plays a central role in the pathogenesis of acute lung injury (ALI), the precise molecular mechanisms underlying the development of this disorder remain poorly understood. SOCS3 is an important negative regulator of IL-6-type cytokine signaling. SOCS3 is induced in lung during LPS-induced lung injury, suggesting that generation of SOCS3 may represent a regulatory product during ALI. In the current study, we created mice lacking SOCS3 expression in macrophages and neutrophils (LysM-cre SOCS3fl/fl). We evaluated the lung inflammatory response to LPS in both LysM-cre SOCS3fl/fl mice and the wild-type (WT) mice (SOCS3fl/fl). LysM-cre SOCS3fl/fl mice displayed significant increase of the lung permeability index (lung vascular leak of albumin), neutrophils, lung neutrophil accumulation (myeloperoxidase activity), and proinflammatory cytokines/chemokines in bronchial alveolar lavage fluids compared to WT mice. These phenotypes were consistent with morphological evaluation of lung, which showed enhanced inflammatory cell influx and intra-alveolar hemorrhage. We further identify the transcription factor, CCAAT/enhancer-binding protein (C/EBP) ? as a critical downstream target of SOCS3 in LPS-induced ALI. These results indicate that SOCS3 has a protective role in LPS-induced ALI by suppressing C/EBP? activity in the lung. Elucidating the function of SOCS3 would represent prospective targets for a new generation of drugs needed to treat ALI.—Yan, C., Ward, P. A., Wang, X., Gao, H. Myeloid depletion of SOCS3 enhances LPS-induced acute lung injury through CCAAT/enhancer binding protein ? pathway. PMID:23585399

Yan, Chunguang; Ward, Peter A.; Wang, Ximo; Gao, Hongwei

2013-01-01

62

LPS-Induced Delayed Preconditioning Is Mediated by Hsp90 and Involves the Heat Shock Response in Mouse Kidney  

PubMed Central

Introduction We and others demonstrated previously that preconditioning with endotoxin (LPS) protected from a subsequent lethal LPS challenge or from renal ischemia-reperfusion injury (IRI). LPS is effective in evoking the heat shock response, an ancient and essential cellular defense mechanism, which plays a role in resistance to, and recovery from diseases. Here, by using the pharmacological Hsp90 inhibitor novobiocin (NB), we investigated the role of Hsp90 and the heat shock response in LPS-induced delayed renal preconditioning. Methods Male C57BL/6 mice were treated with preconditioning (P: 2 mg/kg, ip.) and subsequent lethal (L: 10 mg/kg, ip.) doses of LPS alone or in combination with NB (100 mg/kg, ip.). Controls received saline (C) or NB. Results Preconditioning LPS conferred protection from a subsequent lethal LPS treatment. Importantly, the protective effect of LPS preconditioning was completely abolished by a concomitant treatment with NB. LPS induced a marked heat shock protein increase as demonstrated by Western blots of Hsp70 and Hsp90. NB alone also stimulated Hsp70 and Hsp90 mRNA but not protein expression. However, Hsp70 and Hsp90 protein induction in LPS-treated mice was abolished by a concomitant NB treatment, demonstrating a NB-induced impairment of the heat shock response to LPS preconditioning. Conclusion LPS-induced heat shock protein induction and tolerance to a subsequent lethal LPS treatment was prevented by the Hsp90 inhibitor, novobiocin. Our findings demonstrate a critical role of Hsp90 in LPS signaling, and a potential involvement of the heat shock response in LPS-induced preconditioning. PMID:24646925

Kaucsár, Tamás; Bodor, Csaba; Godó, Mária; Szalay, Csaba; Révész, Csaba; Németh, Zalán; Mózes, Miklós; Szénási, Gábor; Rosivall, László; S?ti, Csaba; Hamar, Péter

2014-01-01

63

Curcumin inhibits LPS-induced CCL2 expression via JNK pathway in C6 rat astrocytoma cells.  

PubMed

The important role of neuroinflammation in many chronic and acute pathological conditions of the central nervous system is widely recognized. Curcumin is a major component of turmeric and reportedly has anti-inflammatory and anti-oxidant effects. This study investigated the inhibitory effect of curcumin on lipopolysacharide (LPS)-induced chemokine CCL2 (or monocyte chemoattractant protein-1, MCP-1) production and whether the effect is mediated by mitogen-activated protein kinases (MAPKs) in the rat astrocytoma cell C6. We observed that LPS (1 ?g/ml) induced the upregulation of CCL2 mRNA and protein in C6. Treatment with curcumin (2.5, 10, and 25 ?M) decreased the expression of CCL2 mRNA and protein in a dose-dependent manner under treatment with LPS. Additionally, the c-jun N-terminal kinase (JNK) inhibitor (SP600125) dose-dependently inhibited LPS-induced CCL2 upregulation, whereas the MAPK kinase (MEK) inhibitor (PD98059) only had a mild effect and the p38 MAPK inhibitor (SB203580) had no effect. Finally, western blot showed that LPS induced rapid JNK activation and curcumin reduced LPS-induced phosphoJNK (pJNK) expression at 30 min after LPS stimulation. These data suggest that the anti-neuroinflammatory effect of curcumin relates to the downregulation of CCL2 expression through the JNK pathway in astrocytoma cells, which indicates a possible benefit from the use of curcumin in the treatment of neuroinflammation-associated disorders. PMID:22410671

Zhang, Zhi-Jun; Zhao, Lin-Xia; Cao, De-Li; Zhang, Xin; Gao, Yong-Jing; Xia, Chunlin

2012-08-01

64

Dexamethasone prevents LPS-induced microglial activation and astroglial impairment in an experimental bacterial meningitis co-culture model.  

PubMed

We analyzed the effect of dexamethasone on gram-negative bacteria derived lipopolysaccharide (LPS) induced inflammation in astroglial/microglial co-cultures. At the cellular level the microglial phenotype converted to an activated type after LPS incubation. Furthermore, LPS compromised functional astroglial properties like membrane resting potential, intracellular coupling and connexin 43 (Cx43) expression. This change in Cx43 expression was not due to a downregulation of Cx43 mRNA expression. Morphological and functional changes were accompanied by a time-dependent release of inflammation related cytokines. Co-incubation of dexamethasone with LPS prevented these LPS-induced changes within our glial co-culture model. The ability of dexamethasone to reconstitute astrocytic properties and to decrease microglial activation in vitro could be one possible explanation for the beneficial effects of dexamethasone in the treatment of acute bacterial meningitis in vivo. PMID:20230803

Hinkerohe, Daniel; Smikalla, Dirk; Schoebel, Andreas; Haghikia, Aiden; Zoidl, Georg; Haase, Claus G; Schlegel, Uwe; Faustmann, Pedro M

2010-05-01

65

The Fusarium toxin deoxynivalenol (DON) modulates the LPS induced acute phase reaction in pigs.  

PubMed

The systemic effects of the Fusarium toxin deoxynivalenol (DON) and of bacterial lipopolysaccharides (LPS) were studied in male castrated pigs (40.4 ± 3.7 kg) infused intravenously with either DON or LPS alone (100 ?g DON/kg/h, 7.5 ?g/LPS/kg/h), or together (100 ?g DON plus 7.5 ?g/LPS/kg/h). The Control group received a saline infusion (n=6/treatment, 24h observation period). An additional DON infusion did not exacerbate the clinical signs observed in LPS-infused pigs. For example, rectal temperature climaxed after 4h (40.4 ± 0.2°C) and 5h (40.1 ± 0.3°C), in the LPS and LPS+DON group, respectively. Saline and DON alone did not induce an acute phase reaction as indicated by unaltered plasma levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) while LPS caused a significant rise of both cytokines. TNF-alpha plasma peak concentrations were significantly higher in the LPS compared to the DON+LPS group (94.3 ± 17.2 ng/mL vs. 79.2 ± 15.7 ng/mL) while IL-6 climaxed earlier in the latter group (3h p.i. vs. 2h p.i.). From the tested clinical-chemical plasma characteristics the total bilirubin concentration and the ASAT activity were strongly elevated by the LPS infusion and additionally increased and decreased by DON, respectively. In conclusion, the LPS-induced effects were only marginally modified by DON. PMID:23603058

Dänicke, Sven; Brosig, Bianca; Kersten, Susanne; Kluess, Jeannette; Kahlert, Stefan; Panther, Patricia; Diesing, Anne-Kathrin; Rothkötter, Hermann-Josef

2013-07-01

66

Blockade of PDE4B limits lung vascular permeability and lung inflammation in LPS-induced acute lung injury.  

PubMed

Acute lung injury (ALI), acute respiratory distress syndrome (ARDS), is actually involved in an ongoing and uncontrolled inflammatory response in lung tissues. Although extensive studies suggested that phospodiesterase type 4B (PDE4B) may be related to inflammation, the underlying cell biological mechanism of ALI remains unclear. To further investigate the mechanism how PDE4B take part in inflammatory response and the maintenance of vascular integrity, we established the experimental model of ALI in vitro and in vivo. In vitro, we found that Cilomilast, Diazepam and PDE4B knockout could potently inhibit the LPS-induced NF-?B activation and inflammatory response in multiple cell types, including lung epithelial cells (A549), pulmonary microvascular endothelial cells (PMVECs) and vascular smooth muscle cells (VSMCs). Besides, PDE4B deletion attenuated the LPS-induced ROS generation. In vivo, PDE4B deletion could attenuate the lung water content, histological signs of pulmonary injury and elevate the ratio of partial pressure of arterial O2 to fraction of inspired O2 (PaO2/FIO2 ratio). Additionally, PDE4B deletion reduced LPS-induced vascular permeability. Collectively, our results strongly indicates that PDE4B is a valid target for anti-ALI. PMID:25019986

Ma, Hongyan; Shi, Jinghui; Wang, Changsong; Guo, Lei; Gong, Yulei; Li, Jie; Gong, Yongtai; Yun, Fengxiang; Zhao, Hongwei; Li, Enyou

2014-08-01

67

Enhanced LPS-induced peritonitis in mice deficiency of cullin 4B in macrophages.  

PubMed

Cullin 4B (CUL4B), a member of the cullin protein family, is a scaffold protein of the CUL4B-RING-E3 ligase complex that ubiquitinates intracellular proteins.CUL4B's targets include cell cycle-regulated proteins and DNA replication-related molecules. In this study, we generated myeloid-specific Cul4b-deficient mice (Cul4b(f/y);LysM-Cre(KI/KI)) to investigate the influence of Cul4b deficiency on innate immunity, especially on the function of macrophages. Our results show that an intraperitoneal injection of lipopolysaccharide (LPS) led to a significant decrease in body weights and increased leukocyte infiltrates with increased chemokines in the peritoneal cavity of Cul4b(f/y);LysM-Cre(KI/KI) mice. However, the proinflammatory cytokines, IL-6 and TNF-? did not increase in LPS-injected Cul4b(f/y);LysM-Cre(KI/KI) mice. Furthermore, bone marrow-derived macrophages from Cul4b(f/y);LysM-Cre(KI/KI) mice secreted higher levels of chemokines but lower levels of TNF-? and IL-6 upon LPS stimulation. Of note, increased proliferation of Cul4b-deficient macrophages was also observed. These results show that myeloid-specific Cul4b deficiency worsens LPS-induced peritonitis. In addition, Cul4b deficiency leads to enhanced DNA replication and proliferation, increased production of chemokines but a decreased production of proinflammatory cytokines of macrophages. Our data highlight a new role of cullin family, CUL4B, in the immune system. PMID:24898386

Hung, M-H; Jian, Y-R; Tsao, C-C; Lin, S-W; Chuang, Y-H

2014-09-01

68

Spirulina Promotes Stem Cell Genesis and Protects against LPS Induced Declines in Neural Stem Cell Proliferation  

PubMed Central

Adult stem cells are present in many tissues including, skin, muscle, adipose, bone marrow, and in the brain. Neuroinflammation has been shown to be a potent negative regulator of stem cell and progenitor cell proliferation in the neurogenic regions of the brain. Recently we demonstrated that decreasing a key neuroinflammatory cytokine IL-1? in the hippocampus of aged rats reversed the age-related cognitive decline and increased neurogenesis in the age rats. We also have found that nutraceuticals have the potential to reduce neuroinflammation, and decrease oxidative stress. The objectives of this study were to determine if spirulina could protect the proliferative potential of hippocampal neural progenitor cells from an acute systemic inflammatory insult of lipopolysaccharide (LPS). To this end, young rats were fed for 30 days a control diet or a diet supplemented with 0.1% spirulina. On day 28 the rats were given a single i.p. injection of LPS (1 mg/kg). The following day the rats were injected with BrdU (50 mg/kg b.i.d. i.p.) and were sacrificed 24 hours after the first injection of BrdU. Quantification of the BrdU positive cells in the subgranular zone of the dentate gyrus demonstrated a decrease in proliferation of the stem/progenitor cells in the hippocampus as a result of the LPS insult. Furthermore, the diet supplemented with spirulina was able to negate the LPS induced decrease in stem/progenitor cell proliferation. In a second set of studies we examined the effects of spirulina either alone or in combination with a proprietary formulation (NT-020) of blueberry, green tea, vitamin D3 and carnosine on the function of bone marrow and CD34+ cells in vitro. Spirulina had small effects on its own and more than additive effects in combination with NT-020 to promote mitochondrial respiration and/or proliferation of these cells in culture. When examined on neural stem cells in culture spirulina increased proliferation at baseline and protected against the negative influence of TNF? to reduce neural stem cell proliferation. These results support the hypothesis that a diet enriched with spirulina and other nutraceuticals may help protect the stem/progenitor cells from insults. PMID:20463965

Bachstetter, Adam D.; Jernberg, Jennifer; Schlunk, Andrea; Vila, Jennifer L.; Hudson, Charles; Cole, Michael J.; Shytle, R. Douglas; Tan, Jun; Sanberg, Paul R.; Sanberg, Cyndy D.; Borlongan, Cesario; Kaneko, Yuji; Tajiri, Naoki; Gemma, Carmelina; Bickford, Paula C.

2010-01-01

69

LPS induces the TNF-alpha-mediated downregulation of rat liver aquaporin-8: role in sepsis-associated cholestasis.  

PubMed

Although bacterial lipopolysaccharides (LPS) are known to cause cholestasis in sepsis, the molecular mechanisms accounting for this effect are only partially known. Because aquaporin-8 (AQP8) seems to facilitate the canalicular osmotic water movement during hepatocyte bile formation, we studied its gene and functional expression in LPS-induced cholestasis. By subcellular fractionation and immunoblotting analysis, we found that 34-kDa AQP8 was significantly decreased by 70% in plasma (canalicular) and intracellular (vesicular) liver membranes. However, expression and subcellular localization of hepatocyte sinusoidal AQP9 were unaffected. Immunohistochemistry for liver AQPs confirmed these observations. Osmotic water permeability (P(f)) of canalicular membranes, measured by stopped-flow spectrophotometry, was significantly reduced (65 +/- 1 vs. 49 +/- 1 microm/s) by LPS, consistent with defective canalicular AQP8 functional expression. By Northern blot analysis, we found that 1.5-kb AQP8 mRNA expression was increased by 80%, suggesting a posttranscriptional mechanism of protein reduction. The tumor necrosis factor-alpha (TNF-alpha) receptor fusion protein TNFp75:Fc prevented the LPS-induced impairment of AQP8 expression and bile flow, suggesting the cytokine TNF-alpha as a major mediator of LPS effect. Accordingly, studies in hepatocyte primary cultures indicated that recombinant TNF-alpha downregulated AQP8. The effect of TNF-alpha was prevented by the lysosomal protease inhibitors leupeptin or chloroquine or by the proteasome inhibitors MG132 or lactacystin, suggesting a cytokine-induced AQP8 proteolysis. In conclusion, our data suggest that LPS induces the TNF-alpha-mediated posttranscriptional downregulation of AQP8 functional expression in hepatocytes, a mechanism potentially relevant to the molecular pathogenesis of sepsis-associated cholestasis. PMID:18174273

Lehmann, Guillermo L; Carreras, Flavia I; Soria, Leandro R; Gradilone, Sergio A; Marinelli, Raúl A

2008-02-01

70

Human umbilical cord mesenchymal stem cells reduce systemic inflammation and attenuate LPS-induced acute lung injury in rats  

PubMed Central

Background Mesenchymal stem cells (MSCs) possess potent immunomodulatory properties and simultaneously lack the ability to illicit immune responses. Hence, MSCs have emerged as a promising candidate for cellular therapeutics for inflammatory diseases. Within the context of this study, we investigated whether human umbilical cord-derived mesenchymal stem cells (UC-MSCs) could ameliorate lipopolysaccharide- (LPS-) induced acute lung injury (ALI) in a rat model. Methods ALI was induced via injection of LPS. Rats were divided into three groups: (1) saline group(control), (2) LPS group, and (3) MSC + LPS group. The rats were sacrificed at 6, 24, and 48 hours after injection. Serum, bronchoalveolar lavage fluid (BALF), and lungs were collected for cytokine concentration measurements, assessment of lung injury, and histology. Results UC-MSCs increased survival rate and suppressed LPS-induced increase of serum concentrations of pro-inflammatory mediators TNF-?, IL-1?, and IL-6 without decreasing the level of anti-inflammatory cytokine IL-10. The MSC + LPS group exhibited significant improvements in lung inflammation, injury, edema, lung wet/dry ratio, protein concentration, and neutrophil counts in the BALF, as well as improved myeloperoxidase (MPO) activity in the lung tissue. Furthermore, UC-MSCs decreased malondialdehyde (MDA) production and increased Heme Oxygenase-1 (HO-1) protein production and activity in the lung tissue. Conclusion UC-MSCs noticeably increased the survival rate of rats suffering from LPS-induced lung injury and significantly reduced systemic and pulmonary inflammation. Promoting anti-inflammatory homeostasis and reducing oxidative stress might be the therapeutic basis of UC-MSCs. PMID:22974286

2012-01-01

71

Lipopolysaccharide (LPS)-induced autophagy is involved in the restriction of Escherichia coli in peritoneal mesothelial cells  

PubMed Central

Background Host cell autophagy is implicated in the control of intracellular pathogen. Escherichia coli (E.coli) is the most common organism caused single-germ enterobacterial peritonitis during peritoneal dialysis. In this study, we investigated autophagy of peritoneal mesothelial cells and its role in defense against E.coli. Results Autophagy in human peritoneal mesothelial cell line (HMrSV5) was induced by lipopolysaccharide (LPS) in a dose-dependent and time-dependent way, which was demonstrated by increased expression of Beclin-1 and light chain 3 (LC3)-II, the accumulation of punctate green fluorescent protein-LC3, and a higher number of monodansylcadaverine-labeled autophagic vacuoles. After incubation of HMrSV5 cells with E.coli following LPS stimulation, both the intracellular bactericidal activity and the co-localization of E.coli (K12-strain) with autophagosomes were enhanced. Conversely, blockade of autophagy with 3-methyladenine, wortmannin or Beclin-1 small-interfering RNA (siRNA) led to a significant reduction in autophagy-associated protein expression, attenuation of intracellular bactericidal activity, and reduced co-localization of E.coli with monodansylcadaverine-labeled autophagosomes. In addition, treatment of HMrSV5 cells with LPS caused a dose-dependent and time-dependent increase in Toll-like receptor 4 (TLR4) expression. Both knockdown of TLR4 with siRNA and pharmacological inhibition of TLR4 with Polymyxin B significantly decreased LPS-induced autophagy. Furthermore, TLR4 siRNA attenuated remarkably LPS-induced intracellular bactericidal activity. Conclusions Our findings demonstrated for the first time that LPS-induced autophagy in peritoneal mesothelial cells could enhance the intracellular bactericidal activity and the co-localization of E.coli with autophagosomes. The activation of TLR4 signaling was involved in this process. These results indicate that LPS-induced autophagy may be a cell-autonomous defense mechanism triggered in peritoneal mesothelial cells in response to E.coli infection. PMID:24219662

2013-01-01

72

Minocycline ameliorates LPS-induced inflammation in human monocytes by novel mechanisms including LOX-1, Nur77 and LITAF inhibition  

PubMed Central

Background Minocycline exhibits anti-inflammatory properties independent of its antibiotic activity, ameliorating inflammatory responses in monocytes and macrophages. However, the mechanisms of minocycline anti-inflammatory effects are only partially understood. Methods Human circulating monocytes were cultured in the presence of lipopolysaccharide (LPS), 50 ng/ml, and minocycline (10–40 µM). Gene expression was determined by RT-PCR, cytokine and prostaglandin E2 (PGE2) release by ELISA, protein expression, phosphorylation and nuclear translocation by Western blotting. Results Minocycline significantly reduced the inflammatory response in LPS-challenged monocytes, decreasing LPS-induced transcription of pro-inflammatory tumor-necrosis factor alpha (TNF-?), interleukin-1 beta, interleukin-6 (IL-6) and cyclooxygenase-2 (COX-2), and the LPS-stimulated TNF-?, IL-6 and PGE2 release. Minocycline inhibited LPS-induced activation of the lectin-like oxidized low density lipoprotein receptor-1 (LOX-1), NF-?B, LPS-induced TNF-? factor (LITAF) and the Nur77 nuclear receptor. Mechanisms involved in the anti-inflammatory effects of minocycline include a reduction of LPS-stimulated p38 mitogen-activated protein kinase (p38 MAPK) activation and stimulation of the phosphoinositide 3-kinase (PI3K)/Akt pathway. Conclusions We provide novel evidence demonstrating that the anti-inflammatory effects of minocycline in human monocytes include, in addition to decreased NF-?B activation, abrogation of the LPS-stimulated LOX-1, LITAF, Nur77 pathways, p38 MAPK inhibition and PI3K/Akt activation. Our results reveal that minocycline inhibits points of convergence of distinct and interacting signaling pathways mediating multiple inflammatory signals which may influence monocyte activation, traffic and recruitment into the brain. General significance Our results in primary human monocytes contribute to explain the profound anti-inflammatory and protective effects of minocycline in cardiovascular and neurological diseases and may have direct translational relevance. PMID:22306153

Pang, Tao; Wang, Juan; Benicky, Julius; Saavedra, Juan M.

2012-01-01

73

miR-135a inhibition protects A549 cells from LPS-induced apoptosis by targeting Bcl-2.  

PubMed

Acute lung injury (ALI) is a severe clinical condition with high morbidity and mortality. Apoptosis is a key pathologic feature of ALI, and Bcl-2 plays an important role during the pathogenesis of ALI via the regulation of apoptosis. However, the regulation of Bcl-2 during ALI, particularly through microRNAs, remains unclear. We hypothesize that certain miRNAs may play deleterious or protective roles in ALI via the regulation of Bcl-2. The LPS stimulation of A549 cells was used to mimic ALI in vitro. First, we confirmed that Bcl-2 is involved in LPS-induced apoptosis in A549 cells. Then, bioinformatic analyses and quantitative real-time polymerase chain reaction assays were performed to screen for miRNAs targeting Bcl-2. We observed that miR-135a was markedly increased in LPS-challenged A549 cells. miR-135a inhibition markedly restored Bcl-2 expression and protected A549 cells from LPS-induced apoptosis. Furthermore, bioinformatic analysis and luciferase activity assays were conducted to confirm that miR-135a binds directly to the 3'-untranslated region of Bcl-2 and suppresses its expression. Interestingly, the inhibition of miR-135a did not attenuate apoptosis under LPS-treated conditions when Bcl-2 was knocked down. Therefore, we suggest that miR-135a regulation of LPS-induced apoptosis in A549 cells may depend in part on the regulation of Bcl-2. The miR-135a/Bcl-2 signaling pathway may be a novel therapeutic target for the prevention of ALI. PMID:25230140

Zhao, Jing; Li, Xu; Zou, Ming; He, Jing; Han, Yingmin; Wu, Dianbin; Yang, Huafeng; Wu, Jianlin

2014-10-01

74

Usnic acid protects LPS-induced acute lung injury in mice through attenuating inflammatory responses and oxidative stress.  

PubMed

Usnic acid is a dibenzofuran derivative found in several lichen species, which has been shown to possess several activities, including antiviral, antibiotic, antitumoral, antipyretic, analgesic, antioxidative and anti-inflammatory activities. However, there were few reports on the effects of usnic acid on LPS-induced acute lung injury (ALI). The aim of our study was to explore the effect and possible mechanism of usnic acid on LPS-induced lung injury. In the present study, we found that pretreatment with usnic acid significantly improved survival rate, pulmonary edema. In the meantime, protein content and the number of inflammatory cells in bronchoalveolar lavage fluid (BALF) significantly decreased, and the levels of MPO, MDA, and H2O2 in lung tissue were markedly suppressed after treatment with usnic acid. Meanwhile, the activities of SOD and GSH in lung tissue significantly increased after treatment with usnic acid. Additionally, to evaluate the anti-inflammatory activity of usnic acid, the expression of pro-inflammatory cytokines including tumor necrosis factor alpha (TNF-?), interleukin-6 (IL-6) and anti-inflammatory cytokine IL-10, and chemokines interleukin-8 (IL-8) and macrophage inflammatory protein-2 (MIP-2) in BALF were studied. The results in the present study indicated that usnic acid attenuated the expression of TNF-?, IL-6, IL-8 and MIP-2. Meanwhile, the improved level of IL-10 in BALF was observed. In conclusion, these data showed that the protective effect of usnic acid on LPS-induced ALI in mice might relate to the suppression of excessive inflammatory responses and oxidative stress in lung tissue. Thus, it was suggested that usnic acid might be a potential therapeutic agent for ALI. PMID:25068825

Su, Zu-Qing; Mo, Zhi-Zhun; Liao, Jin-Bin; Feng, Xue-Xuan; Liang, Yong-Zhuo; Zhang, Xie; Liu, Yu-Hong; Chen, Xiao-Ying; Chen, Zhi-Wei; Su, Zi-Ren; Lai, Xiao-Ping

2014-10-01

75

Walnut extract inhibits LPS-induced activation of BV-2 microglia via internalization of TLR4: possible involvement of phospholipase D2.  

PubMed

Walnuts are a rich source of essential fatty acids, including the polyunsaturated fatty acids alpha-linolenic acid and linoleic acid. Essential fatty acids have been shown to modulate a number of cellular processes in the brain, including the activation state of microglia. Microglial activation can result in the generation of cytotoxic intermediates and is associated with a variety of age-related and neurodegenerative conditions. In vitro, microglial activation can be induced with the bacterial cell wall component lipopolysaccharide (LPS). In the present study, we generated a methanolic extract of English walnuts (Juglans regia) and examined the effects of walnut extract exposure on LPS-induced activation in BV-2 microglial cells. When cells were treated with walnut extract prior to LPS stimulation, production of nitric oxide and expression of inducible nitric oxide synthase were attenuated. Walnut extract also induced a decrease in tumor necrosis-alpha (TNFalpha) production. We further found that walnut extract induced internalization of the LPS receptor, toll-like receptor 4, and that the anti-inflammatory effects of walnut were dependent on functional activation of phospholipase D2. These studies represent the first to describe the anti-inflammatory effects of walnuts in microglia, which could lead to nutritional interventions in the prevention and treatment of neurodegeneration. PMID:20213499

Willis, Lauren M; Bielinski, Donna F; Fisher, Derek R; Matthan, Nirupa R; Joseph, James A

2010-10-01

76

Microbial transformation of deoxyandrographolide and their inhibitory activity on LPS-induced NO production in RAW 264.7 macrophages.  

PubMed

A series of analogues of deoxyandrographolide (1) transformed by Cunninghamella blakesleana AS 3.2004 were isolated and identified by spectral methods including 2D NMR. Among them, 3-oxo-17,19-dihydroxy-7,13-ent-labdadien-15,16-olide (9), 3-oxo-19-hydroxy-1,13-ent-labdadien-15,16-olide (16), 3-oxo-1?-hydroxy-14-deoxy-andrographolide (17) and 3-oxo-2?-hydroxy-14-deoxyandrographolide (18) are new compounds. And their structure-activity relationships (SAR) of inhibitory activity on LPS-induced NO production in RAW 264.7 macrophage cells were also discussed. PMID:22264489

Deng, Sa; Zhang, Bao Jing; Wang, Chang Yuan; Tian, Yan; Yao, Ji Hong; An, Lei; Huang, Shan Shan; Peng, Jin Yong; Liu, Ke Xin; Ma, Xiao Chi

2012-02-15

77

Aged Black Garlic Exerts Anti-Inflammatory Effects by Decreasing NO and Proinflammatory Cytokine Production with Less Cytoxicity in LPS-Stimulated RAW 264.7 Macrophages and LPS-Induced Septicemia Mice.  

PubMed

Abstract In this study, the anti-inflammatory and antisepticemic activities of a water extract of aged black garlic (AGE), which is not pungent, were compared with those of raw garlic extract (RGE). The methyl thiazolyl tetrazolium (MTT) assay showed that AGE was not toxic up to 1000 ?g/mL and was at least four times less cytotoxic than RGE. AGE significantly suppressed the production of nitric oxide (NO), tumor-necrosis factor-? (TNF-?), and prostaglandin (PG)-E2 in a dose-dependent manner in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Furthermore, the inhibitory effect of AGE on LPS-induced inflammation was confirmed by downregulation of inducible NO synthase and TNF-? mRNA expression, as well as cyclooxygenase-2 protein expression. The anti-inflammatory activities of AGE were similar to those of RGE at nontoxic concentrations up to 250 ?g/mL. Signal transduction pathway studies further indicated that both garlic extracts inhibited activation of mitogen-activated protein kinase and nuclear factor-?B induced by LPS stimulation. Treatment with both AGE and RGE in an in vivo experiment of LPS-induced endotoxemia significantly reduced the level of TNF-? and interleukin-6 in serum and completely protected against LPS-induced lethal shock in C57BL/6 mice. The results suggest that AGE is a more promising nutraceutical or medicinal agent to prevent or cure inflammation-related diseases for safety aspects compared with RGE. PMID:25238199

Kim, Min Jee; Yoo, Yung Choon; Kim, Hyun Jung; Shin, Suk Kyung; Sohn, Eun Jeong; Min, A Young; Sung, Nak Yun; Kim, Mee Ree

2014-10-01

78

Lipid emulsions differentially affect LPS-induced acute monocytes inflammation: in vitro effects on membrane remodeling and cell viability.  

PubMed

The aim of this study was to assess how lipid emulsions for parenteral nutrition affect lipopolysaccharide (LPS)-induced acute monocyte inflammation in vitro. An 18 h long LPS induced human monocyte leukemia cell stimulation was performed and the cell-growth medium was supplemented with three different industrial lipid emulsions: Intralipid(®), containing long-chain triglycerides (LCT-soybean oil); Medialipid(®), containing LCT (soybean oil) and medium-chain triglycerides (MCT-coconut oil); and SMOFlipid(®), containing LCT, MCT, omega-9 and -3 (soybean, coconut, olive and fish oils). Cell viability and apoptosis were assessed by Trypan blue exclusion and flow cytometry respectively. Monocyte composition and membrane remodeling were studied using gas chromatography and NR12S staining. Microparticles released in supernatant were measured by prothrombinase assay. After LPS challenge, both cellular necrosis and apoptosis were increased (threefold and twofold respectively) and microparticle release was enhanced (sevenfold) after supplementation with Medialipid(®) compared to Intralipid(®), SMOFlipid(®) and monocytes in the standard medium. The monocytes differentially incorporated fatty acids after lipid emulsion challenge. Finally, lipid-treated cells displayed microparticles characterized by disrupted membrane lipid order, reflecting lipid remodeling of the parental cell plasma membrane. Our data suggest that lipid emulsions differentially alter cell viability, monocyte composition and thereby microparticle release. While MCT have deleterious effects, we have shown that parenteral nutrition emulsion containing LCT or LCT and MCT associated to n-3 and n-9 fatty acids have no effect on endotoxin-induced cell death and inflammation. PMID:25038627

Boisramé-Helms, Julie; Delabranche, Xavier; Klymchenko, Andrey; Drai, Jocelyne; Blond, Emilie; Zobairi, Fatiha; Mely, Yves; Hasselmann, Michel; Toti, Florence; Meziani, Ferhat

2014-11-01

79

16?,17?-Epoxypregnenolone-20-oxime prevent LPS-induced NO production and iNOS expression in BV-2 microglial cells by inhibiting JNK phosphorylation.  

PubMed

The free radical nitric oxide (NO), a main member of neuroinflammatory cytokine and a gaseous molecule produced by activated microglia, has many physiological functions, including neuroinflammation. In the present study, we evaluated the effects of serial 16-dehydropregnenolone-3-acetate derivatives on lipopolysaccharide (LPS)-induced NO production and inducible nitric oxide synthase (iNOS) expression in BV-2 microglial cells. Among the six derivatives tested, the increases in NO production and iNOS expression observed in BV-2 microglial cells after LPS stimulation were significantly inhibited by treatment with 16?, 17?-epoxypregnenolone-20-oxime. Moreover, the inhibitory effect of 16?,17?-epoxypregnenolone-20-oxime on NO production was similar to that of S-methylisothiourea sulfate (SMT), an iNOS inhibitor. Further studies showed that 16?,17?-epoxypregnenolone-20-oxime inhibited c-Jun N-terminal kinase (JNK) phosphorylation but not inhibitor kappa B (I?B)-? degradation. Our data in LPS-stimulated microglia cells suggest that 16?,17?-epoxypregnenolone-20-oxime might be a candidate therapeutic for treatment of NO induced neuroinflammation and could be a novel iNOS inhibitor. PMID:24989001

Sun, Hu-Nan; Jin, Mei-Hua; Han, Bing; Feng, Li; Han, Ying-Hao; Shen, Gui-Nan; Yu, Yong-Zhong; Jin, Cheng-Hao; Lian, Zheng-Xing; Lee, Dong-Soek; Kim, Sun-Uk; Ge, Wen-Zhong; Cui, Yu-Dong

2014-01-01

80

Chitosan oligosaccharides suppress LPS-induced IL-8 expression in human umbilical vein endothelial cells through blockade of p38 and Akt protein kinases  

PubMed Central

Aim: To investigate whether and how COS inhibited IL-8 production in LPS-induced human umbilical vein endothelial cells (HUVECs). Methods: RT-PCR, enzyme-linked immunosorbent assays (ELISA) and Western blotting were used to study IL-8 expression and related signaling pathway. Wound healing migration assays and monocytic cell adhesion analysis were used to explore the chemotactic and adhesive activities of HUVECs. Results COS 50–200 ?g/mL exerted a significant inhibitory effect on LPS 100 ng/mL-induced IL-8 expression in HUVECs at both the transcriptional and translational levels. In addition, COS 50–200 ?g/mL inhibited LPS-induced HUVEC migration and U937 monocyte adhesion to HUVECs in a concentration-dependent manner. Signal transduction studies suggest that COS blocked LPS-induced activation of nuclear factor-?B (NF-?B) and activator protein-1 (AP-1) as well as phosphorylation of p38 mitogen-activated protein kinase (MAPK) and phosphokinase Akt. Further, the over-expression of LPS-induced IL-8 mRNA in HUVECs was suppressed by a p38 MAPK inhibitor (SB203580, 25 ?mol/L) or a phosphatidylinositol 3-kinase (PI3K) inhibitor (LY294002, 50 ?mol/L). Conclusion: COS inhibited LPS-induced IL-8 expression in HUVECs through the blockade of the p38 MAPK and PI3K/Akt signaling pathways. PMID:21468084

Liu, Hong-tao; Huang, Pei; Ma, Pan; Liu, Qi-shun; Yu, Chao; Du, Yu-guang

2011-01-01

81

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) prevents lipopolysaccharide (LPS)-induced, sepsis-related severe acute lung injury in mice  

PubMed Central

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is an energy metabolism-related enzyme in the glycolytic pathway. Recently, it has been reported that GAPDH has other physiological functions, such as apoptosis, DNA repair and autophagy. Some in vitro studies have indicated immunological aspects of GAPDH function, although there is no definite study discussing the advantage of GAPDH as a therapeutic target. Here, we show that GAPDH has an anti-inflammatory function by using a lipopolysaccharide (LPS)-induced, sepsis-related severe acute lung injury (ALI) mouse model, which is referred to as acute respiratory distress syndrome (ARDS) in humans. GAPDH pre-injected mice were protected from septic death, and their serum levels of proinflammatory cytokines were significantly suppressed. In lung tissue, LPS-induced acute injury and neutrophil accumulation were strongly inhibited by GAPDH pre-injection. Pulmonary, proinflammatory cytokine gene expression and serum chemokine expression in GAPDH pre-injected mice were also reduced. These data suggest the therapeutic potential of GAPDH for sepsis-related ALI/ARDS. PMID:24902773

Takaoka, Yuki; Goto, Shigeru; Nakano, Toshiaki; Tseng, Hui-Peng; Yang, Shih-Ming; Kawamoto, Seiji; Ono, Kazuhisa; Chen, Chao-Long

2014-01-01

82

A TLR4/MD2 fusion protein inhibits LPS-induced pro-inflammatory signaling in hepatic stellate cells  

SciTech Connect

Activated hepatic stellate cells (HSCs) play a key role in hepatic fibrogenesis. In injured liver they are the main extracellular matrix protein producing cell type and further perpetuate hepatic injury by secretion of pro-inflammatory mediators. Since LPS-mediated signaling through toll-like receptor 4 (TLR4) has been identified as key fibrogenic signal in HSCs we aimed to test TLR4 as potential target of therapy via ligand-binding soluble receptors. Incubation of human HSCs with a fusion protein between the extracellular domain of TLR4 and MD2 which binds LPS inhibited LPS-induced NF{kappa}B and JNK activation. TLR4/MD2 abolished LPS-induced secretion of IL-6, IL-8, MCP1, and RANTES in HSCs. In addition, TLR4/MD2 fused to human IgG-Fc neutralized LPS activity. Since TLR4 mutant mice are resistant to liver fibrosis, the TLR4/MD2 soluble receptor might represent a new therapeutic molecule for liver fibrogenesis in vivo.

Schnabl, Bernd [Department of Medicine, University of California San Diego, 9500 Gilman Drive, MC0702, La Jolla, CA 92093 (United States)], E-mail: beschnabl@ucsd.edu; Brandl, Katharina; Fink, Marina; Gross, Philipp [Department of Internal Medicine I, University of Regensburg (Germany); Taura, Kojiro [Department of Medicine, University of California San Diego, 9500 Gilman Drive, MC0702, La Jolla, CA 92093 (United States); Gaebele, Erwin; Hellerbrand, Claus; Falk, Werner [Department of Internal Medicine I, University of Regensburg (Germany)

2008-10-17

83

Apigenin Protects Endothelial Cells from Lipopolysaccharide (LPS)-Induced Inflammation by Decreasing Caspase-3 Activation and Modulating Mitochondrial Function  

PubMed Central

Acute and chronic inflammation is characterized by increased reactive oxygen species (ROS) production, dysregulation of mitochondrial metabolism and abnormal immune function contributing to cardiovascular diseases and sepsis. Clinical and epidemiological studies suggest potential beneficial effects of dietary interventions in inflammatory diseases but understanding of how nutrients work remains insufficient. In the present study, we evaluated the effects of apigenin, an anti-inflammatory flavonoid abundantly found in our diet, in endothelial cells during inflammation. Here, we show that apigenin reduced lipopolysaccharide (LPS)-induced apoptosis by decreasing ROS production and the activity of caspase-3 in endothelial cells. Apigenin conferred protection against LPS-induced mitochondrial dysfunction and reestablished normal mitochondrial complex I activity, a major site of electron leakage and superoxide production, suggesting its ability to modulate endothelial cell metabolic function during inflammation. Collectively, these findings indicate that the dietary compound apigenin stabilizes mitochondrial function during inflammation preventing endothelial cell damage and thus provide new translational opportunities for the use of dietary components in the prevention and treatment of inflammatory diseases. PMID:23989609

Duarte, Silvia; Arango, Daniel; Parihar, Arti; Hamel, Patrice; Yasmeen, Rumana; Doseff, Andrea I.

2013-01-01

84

Resveratrol Inhibits LPS-Induced MAPKs Activation via Activation of the Phosphatidylinositol 3-Kinase Pathway in Murine RAW 264.7 Macrophage Cells  

PubMed Central

Background Resveratrol is a natural polyphenolic compound that has cardioprotective, anticancer and anti-inflammatory properties. We investigated the capacity of resveratrol to protect RAW 264.7 cells from inflammatory insults and explored mechanisms underlying inhibitory effects of resveratrol on RAW 264.7 cells. Methodology/Principal Findings Murine RAW 264.7 cells were treated with resveratrol (1, 5, and 10 µM) and/or LPS (5 µg/ml). Nitric oxide (NO) and prostaglandin E2 (PGE2) were measured by Griess reagent and ELISA. The mRNA and protein levels of proinflammatory proteins and cytokines were analysed by ELISA, RT-PCR and double immunofluorescence labeling, respectively. Phosphorylation levels of Akt, cyclic AMP-responsive element-binding protein (CREB), mitogen-activated protein kinases (MAPKs) cascades, AMP-activated protein kinase (AMPK) and expression of SIRT1(Silent information regulator T1) were measured by western blot. Wortmannin (1 µM), a specific phosphatidylinositol 3-kinase (PI3-K) inhibitor, was used to determine if PI3-K/Akt signaling pathway might be involved in resveratrol’s action on RAW 264.7 cells. Resveratrol significantly attenuated the LPS-induced expression of nitric oxide (NO), prostaglandin E2 (PGE2), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-? (TNF-?) and interleukin-1? (IL-1?) in RAW 264.7 cells. Resveratrol increased Akt phosphorylation in a time-dependent manner. Wortmannin, a specific phosphatidylinositol 3-kinase (PI3-K) inhibitor, blocked the effects of resveratrol on LPS-induced RAW 264.7 cells activation. In addition, PI3-K inhibition partially abolished the inhibitory effect of resveratrol on the phosphorylation of cyclic AMP-responsive element-binding protein (CREB) and mitogen-activated protein kinases (MAPKs) cascades. Meanwhile, PI3-K is essential for resveratrol-mediated phosphorylation of AMPK and expression of SIRT1. Conclusion and Implications This investigation demonstrates that PI3-K/Akt activation is an important signaling in resveratrol-mediated activation of AMPK phosphorylation and SIRT1 expression, and inhibition of phosphorylation of CREB and MAPKs activation, proinflammatory mediators and cytokines production in response to LPS in RAW 264.7 cells. PMID:22952890

Liu, Bin; Deng, Yi-Shu; Zhan, Dong; Chen, Yuan-Li; He, Ying; Liu, Jing; Zhang, Zong-Ji; Sun, Jun; Lu, Di

2012-01-01

85

Protective effect of rutin on LPS-induced acute lung injury via down-regulation of MIP-2 expression and MMP-9 activation through inhibition of Akt phosphorylation.  

PubMed

Lipopolysaccharide (LPS), also called endotoxin, is the important pathogen of acute lung injury (ALI), which is a clinical syndrome that still lacks effective therapeutic medicine. Rutin belongs to vitamin P and possesses various beneficial effects. In this study, we investigate the potential protective effects and the mechanisms of rutin on LPS-induced ALI. Pre-administration with rutin inhibited LPS-induced arterial blood gas exchange and neutrophils infiltration in the lungs. LPS-induced expression of macrophage inflammatory protein (MIP)-2 and activation of matrix metalloproteinase (MMP)-9 were suppressed by rutin. In addition, the inhibitory concentration of rutin on phosphorylation of Akt was similar as MIP-2 expression and MMP-9 activation. In conclusion, rutin is a potential protective agent for ALI via suppressing the blood gas exchange and neutrophil infiltration. The mechanism of rutin is down-regulation of MIP-2 expression and MMP-9 activation through inhibition of Akt phosphorylation. PMID:25091621

Chen, Wen-Ying; Huang, Yi-Chun; Yang, Ming-Ling; Lee, Chien-Ying; Chen, Chun-Jung; Yeh, Chung-Hsin; Pan, Pin-Ho; Horng, Chi-Ting; Kuo, Wu-Hsien; Kuan, Yu-Hsiang

2014-10-01

86

In vivo Angiotensin II AT1 receptor blockade selectively inhibits LPS-induced innate immune response and ACTH release in rat pituitary gland  

PubMed Central

Systemic lipopolysaccharide (LPS) administration induces an innate immune response and stimulates the hypothalamic-pituitary-adrenal axis. We studied Angiotensin II AT1 receptor participation in the LPS effects with focus on the pituitary gland. LPS (50 ?g/kg, i.p.) enhanced, 3 hours after administration, gene expression of pituitary CD14 and that of Angiotensin II AT1A receptors in pituitary and hypothalamic paraventricular nucleus (PVN); stimulated ACTH and corticosterone release; decreased pituitary CRF1 receptor mRNA and increased all plasma and pituitary pro-inflammatory factors studied. The AT1 receptor blocker (ARB) candesartan (1 mg/kg/day, s.c. daily for 3 days before LPS) blocked pituitary and PVN AT1 receptors, inhibited LPS-induced ACTH but not corticosterone secretion and decreased LPS-induced release of TNF-?, IL-1? and IL-6 to the circulation. The ARB reduced LPS-induced pituitary gene expression of IL-6, LIF, iNOS, COX-2 and I?B-?; and prevented LPS-induced increase of nNOS/eNOS activity. The ARB did not affect LPS-induced TNF-? and IL-1? gene expression, IL-6 or IL-1?protein content or LPS-induced decrease of CRF1 receptors. When administered alone, the ARB increased basal plasma corticosterone levels and basal PGE2 mRNA in pituitary. Our results demonstrate that the pituitary gland is a target for systemically administered LPS. AT1 receptor activity is necessary for the complete pituitary response to LPS and is limited to specific pro-inflammatory pathways. There is a complementary and complex influence of the PVN and circulating cytokines on the initial pituitary response to LPS. Our findings support the proposal that ARBs may be considered for the treatment of inflammatory conditions. PMID:19427376

Sanchez-Lemus, Enrique; Benicky, Julius; Pavel, Jaroslav; Saavedra, Juan M.

2009-01-01

87

NAC attenuates LPS-induced toxicity in aspirin-sensitized mouse macrophages via suppression of oxidative stress and mitochondrial dysfunction.  

PubMed

Bacterial endotoxin lipopolysaccharide (LPS) induces the production of inflammatory cytokines and reactive oxygen species (ROS) under in vivo and in vitro conditions. Acetylsalicylic acid (ASA, aspirin) is a commonly used anti-inflammatory drug. Our aim was to study the effects of N-acetyl cysteine (NAC), an antioxidant precursor of GSH synthesis, on aspirin-sensitized macrophages treated with LPS. We investigated the effects of LPS alone and in conjunction with a sub-toxic concentration of ASA, on metabolic and oxidative stress, apoptosis, and mitochondrial function using J774.2 mouse macrophage cell line. Protection from LPS-induced toxicity by NAC was also studied. LPS alone markedly induced ROS production and oxidative stress in macrophage cells. When ASA was added to LPS-treated macrophages, the increase in oxidative stress was significantly higher than that with LPS alone. Similarly, alteration in glutathione-dependent redox metabolism was also observed in macrophages after treatment with LPS and ASA. The combination of LPS and ASA selectively altered the CYP 3A4, CYP 2E1 and CYP 1A1 catalytic activities. Mitochondrial respiratory complexes and ATP production were also inhibited by LPS-ASA treatment. Furthermore a higher apoptotic cell death was also observed in LPS-ASA treated macrophages. NAC pre-treatment showed protection against oxidative stress induced apoptosis and mitochondrial dysfunction. These effects are presumed, at least in part, to be associated with alterations in NF-?B/Nrf-2 mediated cell signaling. These results suggest that macrophages are more sensitive to LPS when challenged with ASA and that NAC pre-treatment protects the macrophages from these deleterious effects. PMID:25075522

Raza, Haider; John, Annie; Shafarin, Jasmin

2014-01-01

88

Cordycepin inhibits lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF)-? production via activating amp-activated protein kinase (AMPK) signaling.  

PubMed

Tumor necrosis factor (TNF)-? is elevated during the acute phase of Kawasaki disease (KD), which damages vascular endothelial cells to cause systemic vasculitis. In the current study, we investigated the potential role of cordycepin on TNF? expression in both lipopolysaccharide (LPS)-stimulated macrophages and ex vivo cultured peripheral blood mononuclear cells (PBMCs) of KD patients. We found that cordycepin significantly suppressed LPS-induced TNF? expression and production in mouse macrophages (RAW 264.7 cells and bone marrow-derived macrophages (BMDMs)). Meanwhile, cordycepin alleviated TNF? production in KD patients' PBMCs. PBMCs from healthy controls had a much lower level of basal TNF-? content than that of KD patients. LPS-induced TNF-? production in healthy controls' PBMCs was also inhibited by cordycepin. For the mechanism study, we discovered that cordycepin activated AMP-activated protein kinase (AMPK) signaling in both KD patients' PBMCs and LPS-stimulated macrophages, which mediated cordycepin-induced inhibition against TNF? production. AMPK inhibition by its inhibitor (compound C) or by siRNA depletion alleviated cordycepin's effect on TNF? production. Further, we found that cordycepin inhibited reactive oxygen species (ROS) production and nuclear factor kappa B (NF-?B) activation in LPS-stimulate RAW 264.7 cells or healthy controls' PBMCs. PBMCs of KD patients showed higher basal level of ROS and NF-?B activation, which was also inhibited by cordycepin co-treatment. In conclusion, our data showed that cordycepin inhibited TNF? production, which was associated with AMPK activation as well as ROS and NF-?B inhibition. The results of this study should have significant translational relevance in managing this devastating disease. PMID:25007068

Zhang, Jian-Li; Xu, Ying; Shen, Jie

2014-01-01

89

Noninvasive molecular imaging reveals role of PAF in leukocyte-endothelial interaction in LPS-induced ocular vascular injury  

PubMed Central

Uveitis is a systemic immune disease and a common cause of blindness. The eye is an ideal organ for light-based imaging of molecular events underlying vascular and immune diseases. The phospholipid platelet-activating factor (PAF) is an important mediator of inflammation, the action of which in endothelial and immune cells in vivo is not well understood. The purpose of this study was to investigate the role of PAF in endothelial injury in uveitis. Here, we use our recently introduced in vivo molecular imaging approach in combination with the PAF inhibitors WEB 2086 (WEB) and ginkgolide B (GB). The differential inhibitory effects of WEB and GB in reducing LPS-induced endothelial injury in the choroid indicate an important role for PAF-like lipids, which might not require the PAF receptor for their signaling. P-selectin glycoprotein ligand-1-mediated rolling of mouse leukocytes on immobilized P-selectin in our autoperfused microflow chamber assay revealed a significant reduction in rolling velocity on the cells' contact with PAF. Rolling cells that came in contact with PAF rapidly assumed morphological signs of cell activation, indicating that activation during rolling does not require integrins. Our results show a key role for PAF in mediating endothelial and leukocyte activation in acute ocular inflammation. Our in vivo molecular imaging provides a detailed view of cellular and molecular events in the complex physiological setting.—Garland, R. C., Sun, D., Zandi, S., Xie, F., Faez, S., Tayyari, F., Frimmel, S. A. F., Schering, A., Nakao, S., Hafezi-Moghadam, A. Noninvasive molecular imaging reveals role of PAF in leukocyte-endothelial interaction in LPS-induced ocular vascular injury. PMID:21257713

Garland, Rebecca C.; Sun, Dawei; Zandi, Souska; Xie, Fang; Faez, Sepideh; Tayyari, Faryan; Frimmel, Sonja A. F.; Schering, Alexander; Nakao, Shintaro; Hafezi-Moghadam, Ali

2011-01-01

90

Effect of indomethacin on LPS-induced fever and on hyperthermia induced by physical restraint in the silver fox ( Vulpes vulpes)  

Microsoft Academic Search

1.1. The effects of indomethacin on LPS-induced fever, and on hyperthermia induced by physical restraint, were investigated in the silver fox (Vulpes vulpes).2.2. Base levels of deep body temperature (Tb) in undisturbed silver foxes measured with surgically implanted transmitters was 38.6°C (±0.1).3.3. Rectal temperature (Tre) five hours after treatment with LPS was 40.1°C (±0.1), indicating a febrile response.4.4. Tre in

Randi Oppermann Moe; Morten Bakken

1997-01-01

91

Curcumin abrogates LPS-induced proinflammatory cytokines in RAW 264.7 macrophages. Evidence for novel mechanisms involving SOCS-1, -3 and p38 MAPK  

PubMed Central

Curcumin is the active compound in the extract of Curcuma longa rhizomes with anti-inflammatory properties mediated by inhibition of intracellular signalling. SOCS and MAPKinases are involved in the signalling events controlling the expression of IL-6, TNF-? and PGE2, which have important roles on chronic inflammatory diseases. The aim was to assess if these pathways are involved in curcumin-mediated effects on LPS-induced expression of these cytokines in macrophages. RAW 264.7 murine macrophages were stimulated with Escherichia coli LPS in the presence and absence of non-cytotoxic concentrations of curcumin. Curcumin potently inhibited LPS-induced expression of IL-6, TNF-? and COX-2 mRNA and prevented LPS-induced inhibition of SOCS-1 and -3 expression and the inhibition of the activation of p38 MAPKinase by modulation of its nuclear translocation. In conclusion, curcumin potently inhibits expression of LPS-induced inflammatory cytokines in macrophages via mechanisms that involve modulation of expression and activity of SOCS-1 and SOCS-3 and of p38 MAPK. PMID:24011306

Guimaraes, Morgana Rodrigues; Leite, Fabio Renato Manzoli; Spolidorio, Luis Carlos; Kirkwood, Keith Lough; Rossa, Carlos

2013-01-01

92

Inhibitory effect of 10-hydroxy-trans-2-decenoic acid on LPS-induced IL-6 production via reducing I?B-? expression.  

PubMed

The effect of 10-hydroxy-trans-2-decenoic acid (10H2DA), a major fatty acid component of royal jelly, was investigated on LPS-induced cytokine production in murine macrophage cell line, RAW264 cells. 10H2DA inhibited LPS-induced IL-6 production dose-dependently, but did not inhibit TNF-? production. 10H2DA inhibited LPS-induced NF-?B activation in a dose-dependent fashion. In addition, NF-?B activation induced by over-expression of either MyD88 or Toll/IL-1?receptor domain-containing adaptor inducing IFN-? (TRIF) was also inhibited by 10H2DA. Degradation of I?B-? and phosphorylation of I?B kinase-? were not inhibited by 10H2DA. On the other hand, reduction of LPS-induced I?B-? expression was discovered. Production of lipocalin-2 and granulocyte colony-stimulating factor (G-CSF), which is dependent on I?B-?, was also inhibited by 10H2DA, whereas that of I?B-?-independent cytokines/chemokines, such as IFN-?, murine monocyte chemotactic protein-1 (JE), macrophage inflammatory protein (MIP)-1? and MIP-2, was not. Together, 10H2DA specifically inhibited LPS-induced I?B-? expression, followed by inhibition of I?B-?-dependent gene production. These results suggest that 10H2DA is one of the components of royal jelly to show anti-inflammatory effects and could be a therapeutic drug candidate for inflammatory and autoimmune diseases associated with I?B-? and IL-6 production. PMID:21948282

Sugiyama, Tsuyoshi; Takahashi, Keita; Tokoro, Shunji; Gotou, Takaki; Neri, Paola; Mori, Hiroshi

2012-06-01

93

Pulsatilla decoction and its active ingredients inhibit secretion of NO, ET-1, TNF-alpha, and IL-1 alpha in LPS-induced rat intestinal microvascular endothelial cells.  

PubMed

To investigate the pharmacological mechanism of the traditional Chinese medicine, Pulsatilla decoction (PD), the levels of nitric oxide (NO), endothelin-1 (ET-1), tumor necrosis factor-alpha (TNF-alpha), and interleukin-1 alpha (IL-1 alpha) secreted by cultured rat intestinal microvascular endothelial cells (RIMECs) were determined after treatment with PD and its seven active ingredients, namely anemoside B(4), anemonin, berberine, jatrorrhizine, palmatine, aesculin, and esculetin. RIMECs were challenged with lipopolysaccharide (LPS) at 1 microg ml(-1) for 3 h and then treated with PD at 1, 5, and 10 mg ml(-1) and its seven ingredients at 1, 5, and 10 microg ml(-1) for 21 h, respectively. The results revealed that PD, anemonin, berberine, and esculetin inhibited the production of NO; PD, anemonin, and esculetin inhibited the secretion of ET-1; PD, anemoside B(4), berberine, jatrorrhizine, and aesculin downregulated TNF-alpha expression; PD, anemoside B(4), berberine, and palmatine decreased the content of IL-1 alpha. It showed that PD and its active ingredients could significantly inhibit the secretion of NO, ET-1, TNF-alpha, and IL-1 alpha in LPS-induced RIMECs and suggested they would reduce inflammatory response via these cytokines. PMID:19472295

Hu, Yiyi; Chen, Xi; Duan, Huiqin; Hu, Yuanliang; Mu, Xiang

2009-07-01

94

Functional Toll-like receptor 4 expressed in lactotrophs mediates LPS-induced proliferation in experimental pituitary hyperplasia  

SciTech Connect

Toll like receptor 4 (TLR4) has been characterized for its ability to recognize bacterial endotoxin lipopolysaccharide (LPS). Considering that infections or inflammatory processes might contribute to the progression of pituitary tumors, we analyzed the TLR4 functional role by evaluating the LPS effect on lactotroph proliferation in primary cultures from experimental pituitary tumors, and examined the involvement of PI3K-Akt and NF-?B activation in this effect. In addition, the role of 17?-estradiol as a possible modulator of LPS-induced PRL cell proliferation was further investigated. In estrogen-induced hyperplasic pituitaries, LPS triggered lactotroph cell proliferation. However, endotoxin failed to increase the number of lactotrophs taking up BrdU in normal pituitaries. Moreover, incubation with anti-TLR4 antibody significantly reduced LPS-induced lactotroph proliferation, suggesting a functional role of this receptor. As a sign of TLR4 activation, an LPS challenge increased IL-6 release in normal and tumoral cells. By flow cytometry, TLR4 baseline expression was revealed at the plasma membrane of tumoral lactotrophs, without changes noted in the percentage of double PRL/TLR4 positive cells after LPS stimulus. Increases in TLR4 intracellular expression were detected as well as rises in CD14, p-Akt and NF-?B after an LPS challenge, as assessed by western blotting. The TLR4/PRL and PRL/NF-?B co-localization was also corroborated by immunofluorescence and the involvement of PI3K/Akt signaling in lactotroph proliferation and IL-6 release was revealed through the PI3K inhibitor Ly-294002. In addition, 17?-estradiol attenuated the LPS-evoked increase in tumoral lactotroph proliferation and IL-6 release. Collectively these results demonstrate the presence of functional TLR4 in lactotrophs from estrogen-induced hyperplasic pituitaries, which responded to the proliferative stimulation and IL-6 release induced by LPS through TLR4/CD14, with a contribution of the PI3K-Akt and NF-?B signaling pathways. - Highlights: • In hyperplastic pituitaries, LPS triggered the lactotroph cell proliferation and IL-6 release. • Functional Toll-like receptor 4 (TLR4) is expressed at the plasma membrane of tumoral lactotrophs. • Increases in TLR4 and CD14 intracellular expression levels were detected after an LPS challenge. • The proliferative stimulation and IL-6 release involved the PI3K-Akt pathway and NF-?B activation. • 17?-estradiol attenuated the LPS-evoked tumoral lactotroph proliferation and IL-6 secretion.

Sabatino, María Eugenia; Sosa, Liliana del Valle; Petiti, Juan Pablo; Mukdsi, Jorge Humberto [Centro de Microscopía Electrónica, Instituto de Investigaciones en Ciencias de la Salud (INICSA-CONICET), Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Av. Enrique Barros y Enfermera Gordillo, Ciudad Universitaria, CP 5000, Córdoba (Argentina); Mascanfroni, Iván Darío; Pellizas, Claudia Gabriela [Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Av. Haya de la Torre y Medina Allende, Ciudad Universitaria, CP 5000, Córdoba (Argentina); Gutiérrez, Silvina; Torres, Alicia Inés [Centro de Microscopía Electrónica, Instituto de Investigaciones en Ciencias de la Salud (INICSA-CONICET), Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Av. Enrique Barros y Enfermera Gordillo, Ciudad Universitaria, CP 5000, Córdoba (Argentina); De Paul, Ana Lucía, E-mail: adepaul@cmefcm.uncor.edu [Centro de Microscopía Electrónica, Instituto de Investigaciones en Ciencias de la Salud (INICSA-CONICET), Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Av. Enrique Barros y Enfermera Gordillo, Ciudad Universitaria, CP 5000, Córdoba (Argentina)

2013-11-15

95

?? adrenoceptor activation by norepinephrine inhibits LPS-induced cardiomyocyte TNF-? production via modulating ERK1/2 and NF-?B pathway.  

PubMed

Cardiomyocyte tumour necrosis factor ? (TNF-?) production contributes to myocardial depression during sepsis. This study was designed to observe the effect of norepinephrine (NE) on lipopolysaccharide (LPS)-induced cardiomyocyte TNF-? expression and to further investigate the underlying mechanisms in neonatal rat cardiomyocytes and endotoxaemic mice. In cultured neonatal rat cardiomyocytes, NE inhibited LPS-induced TNF-? production in a dose-dependent manner. ??- adrenoceptor (AR) antagonist (prazosin), but neither ??- nor ??-AR antagonist, abrogated the inhibitory effect of NE on LPS-stimulated TNF-? production. Furthermore, phenylephrine (PE), an ??-AR agonist, also suppressed LPS-induced TNF-? production. NE inhibited p38 phosphorylation and NF-?B activation, but enhanced extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation and c-Fos expression in LPS-treated cardiomyocytes, all of which were reversed by prazosin pre-treatment. To determine whether ERK1/2 regulates c-Fos expression, p38 phosphorylation, NF-?B activation and TNF-? production, cardiomyocytes were also treated with U0126, a selective ERK1/2 inhibitor. Treatment with U0126 reversed the effects of NE on c-Fos expression, p38 mitogen-activated protein kinase (MAPK) phosphorylation and TNF-? production, but not NF-?B activation in LPS-challenged cardiomyocytes. In addition, pre-treatment with SB202190, a p38 MAPK inhibitor, partly inhibited LPS-induced TNF-? production in cardiomyocytes. In endotoxaemic mice, PE promoted myocardial ERK1/2 phosphorylation and c-Fos expression, inhibited p38 phosphorylation and I?B? degradation, reduced myocardial TNF-? production and prevented LPS-provoked cardiac dysfunction. Altogether, these findings indicate that activation of ??-AR by NE suppresses LPS-induced cardiomyocyte TNF-? expression and improves cardiac dysfunction during endotoxaemia via promoting myocardial ERK phosphorylation and suppressing NF-?B activation. PMID:24304472

Yu, Xiaohui; Jia, Baoyin; Wang, Faqiang; Lv, Xiuxiu; Peng, Xuemei; Wang, Yiyang; Li, Hongmei; Wang, Yanping; Lu, Daxiang; Wang, Huadong

2014-02-01

96

Alliin, a Garlic (Allium sativum) Compound, Prevents LPS-Induced Inflammation in 3T3-L1 Adipocytes  

PubMed Central

Garlic (Allium sativum L.) has been used to alleviate a variety of health problems due to its high content of organosulfur compounds and antioxidant activity. The main active component is alliin (S-allyl cysteine sulfoxide), a potent antioxidant with cardioprotective and neuroprotective actions. In addition, it helps to decrease serum levels of glucose, insulin, triglycerides, and uric acid, as well as insulin resistance, and reduces cytokine levels. However its potential anti-inflammatory effect is unknown. We examined the effects of alliin in lipopolysaccharide- (LPS-) stimulated 3T3-L1 adipocytes by RT-PCR, Western blot, and microarrays analysis of 22,000 genes. Incubation of cells for 24?h with 100??mol/L alliin prevented the increase in the expression of proinflammatory genes, IL-6, MCP-1, and Egr-1 in 3T3-L1 adipocytes exposed to 100?ng/mL LPS for 1?h. Interestingly, the phosphorylation of ERK1/2, which is involved in LPS-induced inflammation in adipocytes, was decreased following alliin treatment. Furthermore, the gene expression profile by microarrays evidentiate an upregulation of genes involved in immune response and downregulation of genes related with cancer. The present results have shown that alliin is able to suppress the LPS inflammatory signals by generating an anti-inflammatory gene expression profile and by modifying adipocyte metabolic profile. PMID:24453416

Quintero-Fabian, Saray; Ortuno-Sahagun, Daniel; Vazquez-Carrera, Manuel; Lopez-Roa, Rocio Ivette

2013-01-01

97

Imperatorin attenuates LPS-induced inflammation by suppressing NF-?B and MAPKs activation in RAW 264.7 macrophages.  

PubMed

Imperatorin is a type of coumarin compound with antibacterial and antiviral activities. In the present study, we examined the anti-inflammatory effects of imperatorin in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages by investigating its impact on the production and expression of cytokines and the major signal-transduction pathways. We found that imperatorin downregulated LPS-induced levels of TNF-?, IL-1?, and IL-6 in RAW 264.7 macrophages in a concentration-dependent manner, and it significantly inhibited expression of TNF-? and IL-6 (P?

Guo, Weixiao; Sun, Jingjing; Jiang, Lanxiang; Duan, Lingxin; Huo, Meixia; Chen, Na; Zhong, Weiting; Wassy, Lanan; Yang, Zhenguo; Feng, Haihua

2012-12-01

98

POLYCHLORINATED BIPHENYL MIXTURES (AROCLORS) INHIBIT LPS-INDUCED MURINE SPLENOCYTE PROLIFERATION IN VITRO. (R826687)  

EPA Science Inventory

Abstract The immune system is believed to be a sensitive indicator for adverse polychlorinated biphenyl (PCB)-induced health effects. Four commercial PCB mixtures (Aroclors) or six individual PCB congeners were evaluated for their effect on splenocyte viability and lip...

99

CaMKI? regulates AMPK-dependent, TORC-1 independent autophagy during LPS-induced acute lung neutrophilic inflammation1,2  

PubMed Central

Autophagy is an evolutionarily conserved cytoplasmic process regulated by the energy rheostats mTOR and AMPK that recycles damaged or unused proteins and organelles. It has been described as an important effector arm of immune cells. We have shown that the cytoplasmically oriented calcium/calmodulin-dependent protein kinase I ? (CaMKI?) regulates the inflammatory phenotype of the macrophage (M?). Here, we hypothesize that CaMKI? mediates M? autophagy. LPS induced autophagy in RAW 264.7 cells and murine peritoneal M? that was attenuated with biochemical CaMK inhibition or CaMKI? siRNA. Inhibition of CaMKI? reduced LPS-induced p-Thr172AMPK and TORC1 activity, and expression of a constitutively active CaMKI? but not a kinase-deficient mutant induced p-Thr172AMPK and autophagy that was attenuated by the AMPK inhibitor Compound C. Co-immunoprecipitation and in vitro kinase assays demonstrated that CaMKI? activates AMPK, thereby inducing ATG7, which also localizes to this CaMKI?-AMPK complex. During LPS-induced lung inflammation, C57Bl/6 mice receiving CaMKI?siRNA displayed reduced lung and bronchoalveolar immune cell autophagy that correlated with reduced neutrophil recruitment, myeloperoxidase activity, and air space cytokine concentration. Independently inhibiting autophagy, using siRNA targeting the PI3 kinase VPS34, yielded similar reductions in lung autophagy and neutrophil recruitment. Thus, a novel CaMKI?-AMPK pathway is rapidly activated in M? exposed to LPS and regulates an early autophagic response, independent of TORC1 inhibition. These mechanisms appear to be operant in vivo in orchestrating LPS-induced lung neutrophil recruitment and inflammation. PMID:23447692

Guo, Lanping; Stripay, Jennifer L.; Zhang, Xianghong; Collage, Richard D.; Hulver, Mei; Carchman, Evie H.; Howell, Gina M.; Zuckerbraun, Brian S.; Lee, Janet S.; Rosengart, Matthew R.

2013-01-01

100

C-type natriuretic peptide attenuates LPS-induced endothelial activation: involvement of p38, Akt, and NF-?B pathways.  

PubMed

Endothelial activation elicited by inflammatory agents is regarded as a key event in the pathogenesis of several vascular inflammatory diseases. In the present study, the inhibitory effects and underlying mechanism of C-type natriuretic peptide (CNP) on LPS-induced endothelial activation were examined in human umbilical vein endothelial cells (HUVECs). The effect of CNP on adhesion molecule expression was assessed using quantitative real-time RT-PCR and western blotting analyses. The nuclear factor-?B (NF-?B), MAPK, and PI3K/Akt signaling pathways in LPS-stimulated HUVECs were investigated using western blotting analyses, and the production of intracellular reactive oxygen species (ROS) was measured using a fluorescence method. Pretreatment with CNP inhibited LPS-induced expression of intercellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin, and P-selectin in a concentration-dependent manner. CNP suppressed the phosphorylation of p65 and NF-?B activation in LPS-stimulated cells. Moreover, CNP reduced ERK1/2 and p38 phosphorylation induced by LPS but not JNK. Furthermore, CNP induced Akt phosphorylation and activation of hemeoxygenase-1 (HO-1) expression. CNP significantly inhibited the production of intracellular ROS. These results suggest that CNP effectively attenuated LPS-induced endothelial activation by inhibiting the NF-?B and p38 signaling pathways, eliminating LPS-induced intracellular ROS production, and activating the PI3K/Akt/HO-1 pathway in HUVECs; thereby, demonstrating that CNP may be a potential therapeutic target for the treatment of sepsis and inflammatory vascular diseases. PMID:25096521

Chen, Gan; Zhao, Jingxiang; Yin, Yujing; Wang, Bo; Liu, Qingjun; Li, Penglong; Zhao, Lian; Zhou, Hong

2014-12-01

101

Bis-N-norgliovictin, a small-molecule compound from marine fungus, inhibits LPS-induced inflammation in macrophages and improves survival in sepsis.  

PubMed

Sepsis is a highly lethal disorder characterized by systemic inflammation, and Toll-like receptor 4 (TLR4) in macrophages plays a crucial role in modulating innate immune response and outcome of sepsis. During the screening of natural products against inflammation, we identified bis-N-norgliovictin, a small-molecule compound isolated from marine-derived fungus, significantly inhibited lipopolysaccharide (LPS, ligand of TLR4)-induced tumor necrosis factor-? (TNF-?) production in RAW264.7 cells. In this study, we evaluated the effect of bis-N-norgliovictin on TLR4-mediated inflammation in mouse macrophages and LPS-induced sepsis model. In RAW264.7 and mouse peritoneal macrophages, bis-N-norgliovictin dose-dependently inhibited LPS-induced production of TNF-?, interleukin-6 (IL-6), interferon-? (IFN-?) and monocyte chemoattractant protein (MCP-1), but without suppressing cell viability. The anti-inflammatory effect was attributed to the down-regulation of TLR4-triggered myeloid differentiation primary response protein 88 (MyD88)-dependent and TIR-containing adapter inducing interferon-? (TRIF)-dependent signaling pathways, including p38 and c-Jun N-terminal kinase (JNK) of mitogen-activated protein kinases (MAPKs), nuclear factor-?B (NF-?B) and interferon regulatory factor 3 (IRF3) cascades. Importantly, bis-N-norgliovictin also protected mice against LPS-induced endotoxic shock. Intravenous injection of bis-N-norgliovictin 1h before LPS challenge dose-dependently inhibited LPS-induced increases in serum levels of TNF-?, IL-6, MCP-1 and IL-10, attenuated liver and lung injury and diminished M1 macrophage polarization in liver. Our results demonstrate that bis-N-norgliovictin exhibit potent anti-inflammatory effect both in vitro and in vivo. These findings suggest that bis-N-norgliovictin can be a useful therapeutic candidate for the treatment of sepsis and other inflammatory diseases. PMID:23438875

Song, Yuxian; Dou, Huan; Gong, Wei; Liu, Xianqin; Yu, Zhiguo; Li, Erguang; Tan, Renxiang; Hou, Yayi

2013-04-01

102

Interaction between PKR and PACT mediated by LPS-inducible NF-?B in human gingival cells.  

PubMed

The double-stranded RNA-dependent protein kinase (PKR) is a serine/threonine kinase expressed constitutively in mammalian cells. PKR is activated upon virus infection by double-stranded RNA (dsRNA), and plays a critical role in host antiviral defense mechanisms. PKR is also known to regulate various biological responses, including cell differentiation and apoptosis. However, whether PKR is involved in the progress of periodontitis is not clear. The present study explained the phosphorylation of PKR by LPS in the human gingival cell line, Sa3. Expression of genes encoding LPS receptors was detected in Sa3 cells and treatment of cells with 1?µg/mL LPS for 6?h caused PKR phosphorylation. LPS elevated the expression of the protein activator of PKR (PACT) mRNA and protein, followed by the enhanced association between PACT and PKR within 3?h. In addition, LPS treatment induced the translocation of NF-?B to the nucleus after 30?min, and inhibition of NF-?B decreased the PACT-PKR interaction induced by LPS. The level of pro-inflammatory cytokine mRNA, including interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF?), appeared within 45?min and reached at the maximal levels by 90?min after the addition of LPS. This induction of pro-inflammatory cytokines was not affected by RNAi-mediated silencing of PKR and a pharmacological inhibitor of PKR, whereas the inhibition of NF-?B decreased it. These results indicated that LPS induces PKR phosphorylation and the PACT-PKR association in Sa3 cells. Our results also suggest that NF-?B is involved in the PACT-PKR interaction and the production of pro-inflammatory cytokines in periodontitis. PMID:21882225

Yoshida, Kaya; Okamura, Hirohiko; Hoshino, Yumi; Shono, Masayuki; Yoshioka, Masami; Hinode, Daisuke; Yoshida, Hideo

2012-01-01

103

Pretreatment of lipopolysaccharide (LPS) ameliorates D-GalN/LPS induced acute liver failure through TLR4 signaling pathway  

PubMed Central

Endotoxin tolerance (ET) is an important phenomenon, which affects inflammation and phagocytosis. Pretreatment with low dose of lipopolysaccharide (LPS) can protect liver injury from various hepatotoxicants such as acetaminophen and pseudomonas aeruginosa exotoxin A. The current study aimed to investigate the protecting mechanisms of endotoxin tolerance in acute liver failure induced by D-galactosamine (D-GalN)/LPS and possible role of toll-like receptors 4 (TLR4) signaling pathway in this phenomenon. Acute liver failure was induced by Injection of D-GalN/LPS. To mimic endotoxin tolerance, male Sprague-Dawley rats were treated with low dose of LPS (0.1 mg/kg once a day intraperitoneally for consecutive five days) before subsequent injection of D-GalN/LPS. Rat survival was determined by survival rate. Liver injury was confirmed by serum biochemical and liver histopathological examination. Inflammatory cytokines were determined by ELISA and nuclear factor-kappa B (NF-?B) (P65), toll-like receptors 4 (TLR4) and Interleukin-1 receptor-associated kinase-1 (IRAK-1) were measured by reverse transcriptase polymerase chain reaction and western blot respectively. Pretreatment of LPS significantly improved rat survival. Moreover, rats pretreated with LPS exhibited lower serum enzyme (ALT, AST and TBiL) level, lower production of inflammatory cytokines and more minor liver histopathological damage than rats without pretreatment of LPS. LPS pretreatment suppressed production of TLR4 and IRAK-1. LPS pretreatment also inhibited activation of hepatic NF-?B. These results indicated that endotoxin tolerance contributed to liver protection against D-GalN/LPS induced acute liver failure through down-regulation of TLR4 and NF-?B pathway.

Zhang, Sainan; Yang, Naibin; Ni, Shunlan; Li, Wenyuan; Xu, Lanman; Dong, Peihong; Lu, Mingqin

2014-01-01

104

Macrophage Migration Inhibitory Factor Governs Endothelial Cell Sensitivity to LPS-Induced Apoptosis  

Microsoft Academic Search

Human endothelial cells (EC) are typically resistant to the apoptotic effects of stimuli associated with lung disease. The determinants of this resistance remain incompletely understood. Macrophage mi- gration inhibitory factor (MIF) is a proinflammatory cytokine pro- duced by human pulmonary artery EC (HPAEC). Its expression increases in response to various death-inducing stimuli, including lipopolysaccharide (LPS). We show here that silencing

Rachel L. Damico; Alan Chesley; Laura Johnston; Eric P. Bind; Eric Amaro; Julie Nijmeh; Bedri Karakas; Laura Welsh; David B. Pearse; Joe G. N. Garcia; Michael T. Crow

105

Anti-Inflammatory Effects of LK3, on LPS-Induced Sepsis in Rats  

Microsoft Academic Search

Dextromethorphan (DM), an antitussive agent, has been shown to have anti-inflammatory and immunomodulatory effects in vitro. Thus, the aim of this study was to evaluate the effects of LK-3, an analog of DM, on sepsis induced by intravenous (i.v.) administration of lipopolysaccharide (LPS; 10 mg\\/ kg) in anesthetized Wistar rats. Results demonstrated that post-treatment with LK-3 (4 mg\\/kg, i.v.) significantly

Wen-Hui Tsai; Pao-Yun Cheng; Yen-Mei Lee; Min-Chen Chiu; Shyi-Shiaw Jiau; Edwin S. C. Wu; Mao-Hsiung Yen

2008-01-01

106

LPS-induced dental pulp inflammation increases expression of ionotropic purinergic receptors in rat trigeminal ganglion.  

PubMed

Severe toothache can be caused by dental pulp inflammation. The ionotropic purinergic receptor family (P2X) is reported to mediate nociception in primary afferent neurons. This study aims to investigate the involvement of P2X receptors in the sensitization of the trigeminal ganglion (TG) caused by dental pulp inflammation. Lipopolysaccharides were unilaterally applied to the pulp of the upper molar of the rat to induce dental pulp inflammation. Increased expression of c-fos, a marker of neuronal activity, was induced in V1-V2 division, indicating the activation of TG neurons. The expressions of P2X2, P2X3, and P2X5 were also increased in the V1-V2 division of TG, primarily in small-sized and medium-sized neurons. Markers of glutamatergic afferents, VGluT1, and GABAergic afferents, GAD67, were induced by lipopolysaccharides and coexpressed with P2X in small-sized TG neurons. The present findings suggest that the P2X2, P2X3, and P2X5 receptors are upregulated as part of the sensitization produced by dental pulp inflammation. PMID:25055139

Chen, Yangxi; Zhang, Li; Yang, Jingwen; Zhang, Lu; Chen, Zhi

2014-09-10

107

LPS-induced IL10 production in whole blood cultures from chronic fatigue syndrome patients is increased but supersensitive to inhibition by dexamethasone  

Microsoft Academic Search

Several causes have been held responsible for the chronic fatigue syndrome (CFS), including an altered hypothalamus–pituitary–adrenal gland (HPA)-axis activity, viral infections and a reduced Th1 activity. Therefore, it was investigated whether the regulation of IL-10 is different in CFS. LPS-induced cytokine secretion in whole blood cultures showed a significant increase in IL-10 and a trend towards a decrease in IL-12

Jeroen Visser; Willy Graffelman; Bep Blauw; Inge Haspels; Eef Lentjes; E. Ronald de Kloet; Lex Nagelkerken

2001-01-01

108

Upregulation of LPS-induced chemokine KC expression by 15-deoxy-delta12,14-prostaglandin J2 in mouse peritoneal macrophages.  

PubMed

15-Deoxy-Delta(12,14)-prostaglandin J(2) (15d-PGJ(2)) was initially identified as a high affinity natural ligand for the peroxisome proliferator-activated receptor (PPAR)-gamma. Recent studies have shown that it has a potent anti-inflammatory effect by attenuating the expression of proinflammatory mediators in activated macrophages, mainly through the inhibition of nuclear factor (NF)-kappaB-dependent transcription of inflammatory genes. In this study, we investigated the synergistic effect of 15d-PGJ(2) on the expression of LPS-induced chemokine KC mRNA in mouse peritoneal macrophages. The time course of KC mRNA expression in cells stimulated with 15d-PGJ(2) plus LPS simultaneously (15d-PGJ(2)/LPS) showed similar patterns to the cells treated with LPS alone, and 15d-PGJ(2) had no effect on the stability of LPS-induced KC mRNA expression. Although NF-kappaB activity in cells treated with LPS was augmented by 15d-PGJ(2), pyrrolidone dithiocarbamate (PDTC) did not block the synergistic effect of 15d-PGJ(2) on LPS-induced KC mRNA expression. However, the synergistic effect of 15d-PGJ(2) was markedly inhibited when the macrophages were treated with a inhibitor of the mitogen-activated protein kinase (MAPK) signalling pathway, 2'-amino-3'-methoxyflavine (PD98059). Therefore, the mechanism of synergistic action of 15d-PGJ(2) on the expression of LPS-induced KC mRNA in mouse peritoneal macrophages is possibly related to the MAPK signalling pathway, not to NF-kappaB activation. These data may contribute to unravelling some of the different mechanisms contrary to the anti-inflammatory effect of 15d-PGJ(2). PMID:15877607

Kim, Hyo Y; Kim, Hyun K; Kim, Jae R; Kim, Hee S

2005-06-01

109

Lipoxin A4 and Platelet Activating Factor Are Involved in E. coli or LPS-Induced Lung Inflammation in CFTR-Deficient Mice  

PubMed Central

CFTR (cystic fibrosis transmembrane conductance regulator) is expressed by both neutrophils and platelets. Lack of functional CFTR could lead to severe lung infection and inflammation. Here, we found that mutation of CFTR (F508del) or inhibition of CFTR in mice led to more severe thrombocytopenia, alveolar neutrocytosis and bacteriosis, and lower lipoxin A4/MIP-2 (macrophage inhibitory protein-2) or lipoxin A4/neutrophil ratios in the BAL (bronchoalveolar lavage) during acute E. coli pneumonia. In vitro, inhibition of CFTR promotes MIP-2 production in LPS-stimulated neutrophils; however, lipoxin A4 could dose-dependently suppress this effect. In LPS-induced acute lung inflammation, blockade of PSGL-1 (P-selectin glycoprotein ligand-1) or P-selectin, antagonism of PAF by WEB2086, or correction of mutated CFTR trafficking by KM11060 could significantly increase plasma lipoxin A4 levels in F508del relevant to wildtype mice. Concurrently, F508del mice had higher plasma platelet activating factor (PAF) levels and PAF-AH activity compared to wildtype under LPS challenge. Inhibiting hydrolysis of PAF by a specific PAF-AH (PAF-acetylhydrolase) inhibitor, MAFP, could worsen LPS-induced lung inflammation in F508del mice compared to vehicle treated F508del group. Particularly, depletion of platelets in F508del mice could significantly decrease plasma lipoxin A4 and PAF-AH activity and deteriorate LPS-induced lung inflammation compared to control F508del mice. Taken together, lipoxin A4 and PAF are involved in E. coli or LPS-induced lung inflammation in CFTR-deficient mice, suggesting that lipoxin A4 and PAF might be therapeutic targets for ameliorating CFTR-deficiency deteriorated lung inflammation. PMID:24671173

Wu, Haiya; Yang, Jun; Su, Emily M.; Li, Ling; Zhao, Caiqi; Yang, Xi; Gao, Zhaowei; Pan, Mengyao; Sun, Peiyu; Sun, Wei; Jiang, Yiyi; Su, Xiao

2014-01-01

110

Two structurally distinct {kappa}B sequence motifs cooperatively control LPS-induced KC gene transcription in mouse macrophages  

SciTech Connect

The mouse KC gene is an {alpha}-chemokine gene whose transcription is induced in mononuclear phagocytes by LPS. DNA sequences necessary for transcriptional control of KC by LPS were identified in the region flanking the transcription start site. Transient transfection analysis in macrophages using deletion mutants of a 1.5-kb sequence placed in front of the chloramphenicol acetyl transferase (CAT) gene identified an LPS-responsive region between residues -104 and +30. This region contained two {kappa}B sequence motifs. The first motif (position -70 to -59, {kappa}B1) is highly conserved in all three human GRO genes and in the mouse macrophage inflammatory protein-2 (MIP-2) gene. The second {kappa}B motif (position -89 to -78, {kappa}B2) was conserved only between the mouse and the rat KC genes. Consistent with previous reports, the highly conserved {kappa}B site ({kappa}B1) was essential for LPS inducibility. Surprisingly, the distal {kappa}B site ({kappa}B2) was also necessary for optimal response; mutation of either {kappa}B site markedly reduced sensitivity to LPS in RAW264.7 cells and to TNF-{alpha} in NIH 3T3 fibroblasts. Although both {kappa}B1 and {kappa}B2 sequences were able to bind members of the Rel homology family, including NF{kappa}B1 (P50), RelA (65), and c-Rel, the {kappa}B1 site bound these factors with higher affinity and functioned more effectively than the {kappa}B2 site in a heterologous promoter. These findings demonstrate that transcriptional control of the KC gene requires cooperation between two {kappa}B sites and is thus distinct from that of the three human GRO genes and the mouse MIP-2 gene. 71 refs., 8 figs.

Ohmori, Y.; Fukumoto, S.; Hamilton, T.A. [Cleveland Clinic Foundation, Cleveland, OH (United States)

1995-10-01

111

The inhibition of LPS-induced splenocyte proliferation by ortho-substituted and microbially dechlorinated polychlorinated biphenyls is associated with a decreased expression of cyclin D2.  

PubMed

Immunological effects of polychlorinated biphenyls (PCBs) have been demonstrated in our laboratories with the peferential inhibition of lipopolysaccharide (LPS)-induced splenocyte proliferation by ortho-substituted PCB congeners. An investigation of the mechanism behind this immunotoxicity revealed an interruption in the progression of murine lymphocytes from G0/G1 into S phase by Aroclor 1242 and the di-ortho-substituted congener, 2,2'-chlorobiphenyl (CB), whereas, a non-ortho-substituted congener, 4,4'-CB, did not affect cell cycle progression. This interruption of cell cycle progression by 2,2'-CB and Aroclor 1242 was associated with a decreased expression of the cell cycle regulatory protein, cyclin D2, while expression was not affected by exposure to the non-ortho-substituted 4,4'-CB. These results suggest the preferential inhibition of LPS-induced splenocyte proliferation by ortho-substituted congeners is a result of a decreased expression of cyclin D2, which leads to an interruption in cell cycle progression. In addition, PCB mixtures with an increased percentage of chlorines in the ortho position following an environmentally occurring degradation process inhibited LPS-induced proliferation, interrupted cell cycle progression, and decreased cyclin D2 expression. This study provides evidence for a mechanism of action of the immunological effects of ortho-substituted individual congeners as well as environmentally relevant mixtures enriched in congeners with this substitution pattern. PMID:15369849

Smithwick, L Ashley; Quensen, John F; Smith, Andrew; Kurtz, David T; London, Lucille; Morris, Pamela J

2004-11-01

112

Toona sinensis Inhibits LPS-Induced Inflammation and Migration in Vascular Smooth Muscle Cells via Suppression of Reactive Oxygen Species and NF-?B Signaling Pathway  

PubMed Central

Toona sinensis is one of the most popular vegetarian cuisines in Taiwan and it has been shown to possess antioxidant, antiangiogenic, and anticancer properties. In this study, we investigated the antiatherosclerotic potential of aqueous leaf extracts from Toona sinensis (TS; 25–100??g/mL) and its major bioactive compound, gallic acid (GA; 5??g/mL), in LPS-treated rat aortic smooth muscle (A7r5) cells. We found that pretreatment with noncytotoxic concentrations of TS and GA significantly inhibited inflammatory NO and PGE2 production by downregulating their precursors, iNOS and COX-2, respectively, in LPS-treated A7r5 cells. Furthermore, TS and GA inhibited LPS-induced intracellular ROS and their corresponding mediator, p47phox. Notably, TS and GA pretreatment significantly inhibited LPS-induced migration in transwell assays. Gelatin zymography and western blotting demonstrated that treatment with TS and GA suppressed the activity or expression of MMP-9, MMP-2, and t-PA. Additionally, TS and GA significantly inhibited LPS-induced VEGF, PDGF, and VCAM-1 expression. Further investigation revealed that the inhibition of iNOS/COX-2, MMPs, growth factors, and adhesion molecules was associated with the suppression of NF-?B activation and MAPK (ERK1/2, JNK1/2, and p38) phosphorylation. Thus, Toona sinensis may be useful for the prevention of atherosclerosis. PMID:24723997

Yang, Hsin-Ling; Huang, Pei-Jane; Liu, Yi-Ru; Kumar, K. J. Senthil; Hsu, Li-Sung; Lu, Te-Ling; Chia, Yi-Chen; Takajo, Tokuko; Kazunori, Anzai; Hseu, You-Cheng

2014-01-01

113

LPS-inducible factor(s) from activated macrophages mediates cytolysis of Naegleria fowleri amoebae  

SciTech Connect

Soluble cytolytic factors of macrophage origin have previously been described with respect to their tumoricidal activity. The purpose of this study was to investigate the mechanism and possible factor(s) responsible for cytolysis of the amoeba Naegleria fowleri by activated peritoneal macrophages from B6C3F1 mice. Macrophages or conditioned medium (CM) from macrophage cultures were incubated with /sup 3/H-Uridine labeled amoebae. Percent specific release of label served as an index of cytolysis. Bacille Calmette-Guerin (BCG) and Corynebacterium parvum macrophages demonstrated significant cytolysis of amoebae at 24 h with an effector to target ratio of 10:1. Treatment of macrophages with inhibitors of RNA or protein synthesis blocked amoebicidal activity. Interposition of a 1 ..mu..m pore membrane between macrophages and amoebae inhibited killing. Inhibition in the presence of the membrane was overcome by stimulating the macrophages with LPS. CM from SPS-stimulated, but not unstimulated, cultures of activated macrophages was cytotoxic for amoebae. The activity was heat sensitive and was recovered from ammonium sulfate precipitation of the CM. Results indicate that amoebicidal activity is mediated by a protein(s) of macrophage origin induced by target cell contact or stimulation with LPS.

Cleary, S.F.; Marciano-Cabral, F.

1986-03-01

114

Matrix metalloproteinase and elastase activities in LPS-induced acute lung injury in guinea pigs.  

PubMed

Matrix metalloproteinases (MMPs) and elastase are proteolytic enzymes specifically directed against extracellular matrix (ECM) components. They are secreted by inflammatory cells and may consequently contribute to the lesions of the ECM observed during acute pulmonary edema. We therefore evaluated the MMP and elastase activities, which are secreted by cultured alveolar macrophages (AMACs) and polymorphonuclear neutrophils (PMNs) and present in the bronchoalveolar lavage (BAL) fluid in a guinea pig model of acute lung injury induced by intratracheal instillation of lipopolysaccharide (LPS). The control group was given 0.9% NaCl. 24 h after instillation, a BAL was performed, the BAL fluid was separated from the cells by centrifugation, and AMACs and PMNs were separately cultured for 24 h. In BAL fluid from LPS-treated guinea pigs, we found 1) an increase in free gelatinase activity, tested on [3H]gelatin (0.7 +/- 0.2 micrograms.200 microliters BAL fluid-1.48 h-1 vs. 0.2 +/- 0.1 in controls, P < 0.05), and 2) increased total gelatinase activities, as assessed by zymography. The molecular masses of the major gelatinase species found in BAL fluid by zymography were 92 and 68 kDa. The 92-kDa gelatinase was secreted by both AMACs and PMNs, as demonstrated by zymography of their respective culture media. When tested on [3H]elastin, the elastase activity of BAL fluid of LPS-treated animals exhibited no increase, but when tested on a synthetic peptidic substrate [N-succinyl-(L-alanine)3-p-nitro anilide (SLAPN)], increased elastase-like activity was observed (from 17 +/- 4 nmol of SLAPN.200 microliters BAL fluid-1.24 h-1 in control group to 34 +/- 8 in LPS group, P < 0.05). This increase was attributable to the activity of a metalloendopeptidase that was inhibited by the metal chelator EDTA but not by the specific tissue inhibitor of MMPs. PMID:8166290

D'Ortho, M P; Jarreau, P H; Delacourt, C; Macquin-Mavier, I; Levame, M; Pezet, S; Harf, A; Lafuma, C

1994-03-01

115

Preferential Macrophage Recruitment and Polarization in LPS-Induced Animal Model for COPD: Noninvasive Tracking Using MRI  

PubMed Central

Noninvasive imaging of macrophages activity has raised increasing interest for diagnosis of chronic obstructive respiratory diseases (COPD), which make them attractive vehicles to deliver contrast agents for diagnostic or drugs for therapeutic purposes. This study was designed to monitor and evaluate the migration of differently polarized M1 and M2 iron labeled macrophage subsets to the lung of a LPS-induced COPD animal model and to assess their polarization state once they have reached the inflammatory sites in the lung after intravenous injection. Ex vivo polarized bone marrow derived M1 or M2 macrophages were first efficiently and safely labeled with amine-modified PEGylated dextran-coated SPIO nanoparticles and without altering their polarization profile. Their biodistribution in abdominal organs and their homing to the site of inflammation in the lung was tracked for the first time using a free-breathing non-invasive MR imaging protocol on a 4.7T magnet after their intravenous administration. This imaging protocol was optimized to allow both detection of iron labeled macrophages and visualization of inflammation in the lung. M1 and M2 macrophages were successfully detected in the lung starting from 2 hours post injection with no variation in their migration profile. Quantification of cytokines release, analysis of surface membrane expression using flow cytometry and immunohistochemistry investigations confirmed the successful recruitment of injected iron labeled macrophages in the lung of COPD mice and revealed that even with a continuum switch in the polarization profile of M1 and M2 macrophages during the time course of inflammation a balanced number of macrophage subsets predominate. PMID:24598763

Al Faraj, Achraf; Sultana Shaik, Asma; Pureza, Mary Angeline; Alnafea, Mohammad; Halwani, Rabih

2014-01-01

116

Eugenolol and glyceryl-isoeugenol suppress LPS-induced iNOS expression by down-regulating NF-kappaB AND AP-1 through inhibition of MAPKS and AKT/IkappaBalpha signaling pathways in macrophages.  

PubMed

Eugenol and isoeugenol, two components of clover oil, have been reported to possess several biomedical properties, such as anti-inflammatory, antimicrobial and antioxidant effects. This study aims to examine the anti-inflammatory effects of eugenol, isoeugenol and four of their derivatives on expression of inducible nitric oxide synthase (iNOS) activated by lipopolysaccharide (LPS) in mouse macrophages (RAW 264.7), and to investigate molecular mechanisms underlying these effects. We found that two derivatives, eugenolol and glyceryl-isoeugenol, had potent inhibitory effects on LPS-induced upregulation of nitrite levels, iNOS protein and iNOS mRNA. In addition, they both suppressed the release of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) induced by LPS. Moreover, they both attenuated the DNA binding of NF-kB and AP-1, phosphorylation of inhibitory kB-alpha (IkB-alpha), and nuclear translocation of p65 protein induced by LPS. Finally, we demonstrated that glyceryl-isoeugenol suppressed the phosphorylation of ERK1/2, JNK and p38 MAPK, whereas eugenolol suppressed the phosphorylation of ERK1/2 and p38 MAPK. Taken together, these results suggest that that eugenolol and glyceryl-isoeugenol suppress LPS-induced iNOS expression by down-regulating NF-kB and AP-1 through inhibition of MAPKs and Akt/IkB-alpha signaling pathways. Thus, this study implies that eugenolol and glyceryl-isoeugenol may provide therapeutic benefits for inflammatory diseases. PMID:21658309

Yeh, J L; Hsu, J H; Hong, Y S; Wu, J R; Liang, J C; Wu, B N; Chen, I J; Liou, S F

2011-01-01

117

The monoacylglycerol lipase inhibitor JZL184 attenuates LPS-induced increases in cytokine expression in the rat frontal cortex and plasma: differential mechanisms of action  

PubMed Central

Background and purpose JZL184 is a selective inhibitor of monoacylglycerol lipase (MAGL), the enzyme that preferentially catabolizes the endocannabinoid 2-arachidonoyl glycerol (2-AG). Here, we have studied the effects of JZL184 on inflammatory cytokines in the brain and plasma following an acute immune challenge and the underlying receptor and molecular mechanisms involved. Experimental approach JZL184 and/or the CB1 receptor antagonist, AM251 or the CB2receptor antagonist, AM630 were administered to rats 30 min before lipopolysaccharide (LPS). 2 h later cytokine expression and levels, MAGL activity, 2-AG, arachidonic acid and prostaglandin levels were measured in the frontal cortex, plasma and spleen. Key results JZL184 attenuated LPS-induced increases in IL-1?, IL-6, TNF-? and IL-10 but not the expression of the inhibitor of NFkB (I?B?) in rat frontal cortex. AM251 attenuated JZL184-induced decreases in frontal cortical IL-1? expression. Although arachidonic acid levels in the frontal cortex were reduced in JZL184-treated rats, MAGL activity, 2-AG, PGE2 and PGD2 were unchanged. In comparison, MAGL activity was inhibited and 2-AG levels enhanced in the spleen following JZL184. In plasma, LPS-induced increases in TNF-? and IL-10 levels were attenuated by JZL184, an effect partially blocked by AM251. In addition, AM630 blocked LPS-induced increases in plasma IL-1? in the presence, but not absence, of JZL184. Conclusion and implications Inhibition of peripheral MAGL in rats by JZL184 suppressed LPS-induced circulating cytokines that in turn may modulate central cytokine expression. The data provide further evidence for the endocannabinoid system as a therapeutic target in treatment of central and peripheral inflammatory disorders. Linked Articles This article is part of a themed section on Cannabinoids. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2013.169.issue-4 & http://dx.doi.org/10.1111/bph.2012.167.issue-8 PMID:23043675

Kerr, DM; Harhen, B; Okine, BN; Egan, LJ; Finn, DP; Roche, M

2013-01-01

118

Curcumin inhibits LPS-induced inflammation in rat vascular smooth muscle cells in vitro via ROS-relative TLR4-MAPK/NF-?B pathways  

PubMed Central

Aim: To investigate whether curcumin (Cur) suppressed lipopolysaccharide (LPS)-induced inflammation in vascular smooth muscle cells (VSMCs) of rats, and to determine its molecular mechanisms. Methods: Primary rat VSMCs were treated with LPS (1 ?g/L) and Cur (5, 10, or 30 ?mol/L) for 24 h. The levels of MCP-1, TNF-?, and iNOS were measured using ELISA and real-time RT-PCR. NO level was analyzed with the Griess reaction. Western-blotting was used to detect the activation of TLR4, MAPKs, I?B?, NF-?B p65, and the p47phox subunit of NADPH oxidase in the cells. Results: Treatment of VSMCs with LPS dramatically increased expression of inflammatory cytokines MCP-1 and TNF-?, expression of TLR4 and iNOS, and NO production. LPS also significantly increased phosphorylation of I?B?, nuclear translocation of NF-?B (p65) and phosphorylation of MAPKs in VSMCs. Furthermore, LPS significantly increased production of intracellular ROS, and decreased expression of p47phox subunit of NADPH oxidase. Pretreatment with Cur concentration-dependently attenuated all the aberrant changes in LPS-treated VSMCs. The LPS-induced overexpression of MCP-1 and TNF-?, and NO production were attenuated by pretreatment with the ERK inhibitor PD98059, the p38 MAPK inhibitor SB203580, the NF-?B inhibitor PDTC or anti-TLR4 antibody, but not with the JNK inhibitor SP600125. Conclusion: Cur suppresses LPS-induced overexpression of inflammatory mediators in VSMCs in vitro via inhibiting the TLR4-MAPK/NF-?B pathways, partly due to block of NADPH-mediated intracellular ROS production. PMID:23645013

Meng, Zhe; Yan, Chao; Deng, Qian; Gao, Deng-feng; Niu, Xiao-lin

2013-01-01

119

Etazolate abrogates the lipopolysaccharide (LPS)-induced downregulation of the cAMP/pCREB/BDNF signaling, neuroinflammatory response and depressive-like behavior in mice.  

PubMed

Increasing evidence has indicated that immune challenge by bacterial lipopolysaccharide (LPS) induces depressive-like behavior, neuroinflammatory response and upregulates phosphodiesterase-4 (PDE4), an enzyme that specifically hydrolyzes cyclic adenosine monophosphate (cAMP). However, whether the potential PDE4 inhibitor etazolate prevents the LPS-induced depressive-like behavior remains unclear. Here using a model of depression induced by the repeated administration of LPS during 16days, and then investigated the influence of LPS on the expression of PDE4, interleukin-1? (IL-1?) and antidepressant action of etazolate in mice through forced swimming, novelty suppressed feeding, sucrose preference and open-field tests. Our results showed that etazolate pretreatment facilitated the recovery from weight loss and prevented the depressive-like behavior induced by repeated LPS administration. Moreover, the antidepressant action of etazolate was paralleled by significantly reducing the expression levels of PDE4A, PDE4B, PDE4D and IL-1? and up-regulating the cAMP/phosphorylated cAMP response-element binding protein (pCREB)/brain-derived neurotrophic factor (BDNF) signaling in the hippocampus and prefrontal cortex of mice. These results indicate that the effects of etazolate on the depressive-like behavior induced by repeated LPS treatment may partially depend on the inhibition of PDE4 subtypes, the activation of the cAMP/pCREB/BDNF signaling and the anti-inflammatory responses in the hippocampus and prefrontal cortex. PMID:24434771

Guo, J; Lin, P; Zhao, X; Zhang, J; Wei, X; Wang, Q; Wang, C

2014-03-28

120

Aqueous Extract of Gracilaria tenuistipitata Suppresses LPS-Induced NF-?B and MAPK Activation in RAW 264.7 and Rat Peritoneal Macrophages and Exerts Hepatoprotective Effects on Carbon Tetrachloride-Treated Rat  

PubMed Central

In addition to the previous investigations of bioactivity of aqueous extract of the edible Gracilaria tenuistipitata (AEGT) against H2O2-induced DNA damage and hepatitis C virus replication, the purpose of this study is to evaluate the potential therapeutic properties of AEGT against inflammation and hepatotoxicity using lipopolysaccharide (LPS)-stimulated mouse RAW 264.7 cells, primary rat peritoneal macrophages and carbon tetrachloride (CCl4)-induced acute hepatitis model in rats. AEGT concentration-dependently inhibited the elevated RNA and protein levels of inducible nitric oxide synthase and cyclooxygenase-2, thereby reducing nitric oxide and prostaglandin E2 levels, respectively. Moreover, AEGT significantly suppressed the production of LPS-induced proinflammatory cytokines, including interleukin (IL)-1?, IL-6 and tumor necrosis factor-?. These inhibitory effects were associated with the suppression of nuclear factor-kappa B activation and mitogen-activated protein kinase phosphorylation by AEGT in LPS-stimulated cells. In addition, we highlighted the hepatoprotective and curative effects of AEGT in a rat model of CCl4-intoxicated acute liver injury, which was evident from reduction in the elevated serum aspartate aminotransferase and alanine aminotransferase levels as well as amelioration of histological damage by pre-treatment or post-treatment of AEGT. In conclusion, the results demonstrate that AEGT may serve as a potential supplement in the prevention or amelioration of inflammatory diseases. PMID:24475143

Tseng, Chin-Kai; Lin, Chun-Kuang; Chang, Hsueh-Wei; Wu, Yu-Hsuan; Yen, Feng-Lin; Chang, Fang-Rong; Chen, Wei-Chun; Yeh, Chi-Chen; Lee, Jin-Ching

2014-01-01

121

Contribution of CFTR to Alveolar Fluid Clearance by Lipoxin A4 via PI3K/Akt Pathway in LPS-Induced Acute Lung Injury  

PubMed Central

The lipoxins are the first proresolution mediators to be recognized and described as the endogenous “braking signals” for inflammation. We evaluated the anti-inflammatory and proresolution bioactions of lipoxin A4 in our lipopolysaccharide (LPS-)induced lung injury model. We demonstrated that lipoxin A4 significantly improved histology of rat lungs and inhibited IL-6 and TNF-? in LPS-induced lung injury. In addition, lipoxin A4 increased alveolar fluid clearance (AFC) and the effect of lipoxin A4 on AFC was abolished by CFTRinh-172 (a specific inhibitor of CFTR). Moreover, lipoxin A4 could increase cystic fibrosis transmembrane conductance regulator (CFTR) protein expression in vitro and in vivo. In rat primary alveolar type II (ATII) cells, LPS decreased CFTR protein expression via activation of PI3K/Akt, and lipoxin A4 suppressed LPS-stimulated phosphorylation of Akt. These results showed that lipoxin A4 enhanced CFTR protein expression and increased AFC via PI3K/Akt pathway. Thus, lipoxin A4 may provide a potential therapeutic approach for acute lung injury. PMID:23766562

Cheng, Yang; Lian, Qing-Quan; Yang, Li; Qi, Wei; Wu, De-Rong; Zheng, Xia; Liu, Yong-Jian; Li, Wen-Juan; Jin, Sheng-Wei; Smith, Fang Gao

2013-01-01

122

Valsartan, independently of AT1 receptor or PPAR?, suppresses LPS-induced macrophage activation and improves insulin resistance in cocultured adipocytes.  

PubMed

Macrophages are integrated into adipose tissues and interact with adipocytes in obese subjects, thereby exacerbating adipose insulin resistance. This study aimed to elucidate the molecular mechanism underlying the insulin-sensitizing effect of the angiotensin II receptor blocker (ARB) valsartan, as demonstrated in clinical studies. Insulin signaling, i.e., insulin receptor substrate-1 and Akt phosphorylations, in 3T3-L1 adipocytes was impaired markedly by treatment with tumor necrosis factor-? (TNF?) or in the culture medium of lipopolysaccharide (LPS)-stimulated RAW 264.7 murine macrophages, and valsartan had no effects on these impairments. However, in contrast, when cocultured with RAW 264.7 cells using a transwell system, the LPS-induced insulin signaling impairment in 3T3-L1 adipocytes showed almost complete normalization with coaddition of valsartan. Furthermore, valsartan strongly suppressed LPS-induced productions of cytokines such as interleukin (IL)-1?, IL-6, and TNF? with nuclear factor-?B activation and c-Jun NH(2)-terminal kinase phosphorylation in RAW 264.7 and primary murine macrophages. Very interestingly, this effect of valsartan was also observed in THP-1 cells treated with angiotensin II type 1 (AT1) siRNA or a peroxisome proliferator-activated receptor-? (PPAR?) antagonist as well as macrophages from AT1a receptor-knockout mice. We conclude that valsartan suppresses the inflammatory response of macrophages, albeit not via PPAR? or the AT1a receptor. This suppression appears to secondarily improve adipose insulin resistance. PMID:22045314

Iwashita, Misaki; Sakoda, Hideyuki; Kushiyama, Akifumi; Fujishiro, Midori; Ohno, Haruya; Nakatsu, Yusuke; Fukushima, Toshiaki; Kumamoto, Sonoko; Tsuchiya, Yoshihiro; Kikuchi, Takako; Kurihara, Hiroki; Akazawa, Hiroshi; Komuro, Issei; Kamata, Hideaki; Nishimura, Fusanori; Asano, Tomoichiro

2012-02-01

123

Vitamin C Mitigates Oxidative Stress and Tumor Necrosis Factor-Alpha in Severe Community-Acquired Pneumonia and LPS-Induced Macrophages  

PubMed Central

Oxidative stress is an important part of host innate immune response to foreign pathogens. However, the impact of vitamin C on oxidative stress and inflammation remains unclear in community-acquired pneumonia (CAP). We aimed to determine the effect of vitamin C on oxidative stress and inflammation. CAP patients were enrolled. Reactive oxygen species (ROS), DNA damage, superoxide dismutases (SOD) activity, tumor necrosis factor-alpha (TNF-?), and IL-6 were analyzed in CAP patients and LPS-stimulated macrophages cells. MH-S cells were transfected with RFP-LC3 plasmids. Autophagy was measured in LPS-stimulated macrophages cells. Severe CAP patients showed significantly increased ROS, DNA damage, TNF-?, and IL-6. SOD was significantly decreased in severe CAP. Vitamin C significantly decreased ROS, DNA damage, TNF-?, and IL-6. Vitamin C inhibited LPS-induced ROS, DNA damage, TNF-?, IL-6, and p38 in macrophages cells. Vitamin C inhibited autophagy in LPS-induced macrophages cells. These findings indicated that severe CAP exhibited significantly increased oxidative stress, DNA damage, and proinflammatory mediator. Vitamin C mitigated oxidative stress and proinflammatory mediator suggesting a possible mechanism for vitamin C in severe CAP.

Chen, Yuanyuan; Luo, Guangyan; Yuan, Jiao; Wang, Yuanyuan; Yang, Xiaoqiong; Wang, Xiaoyun; Li, Guoping; Liu, Zhiguang; Zhong, Nanshan

2014-01-01

124

Anti-Inflammatory and Anticoagulative Effects of Paeonol on LPS-Induced Acute Lung Injury in Rats  

PubMed Central

Paeonol is an active component of Moutan Cortex Radicis and is widely used as an analgesic, antipyretic, and anti-inflammatory agent in traditional Chinese medicine. We wanted to determine the role of paeonol in treating adult respiratory distress syndrome (ARDS). We established an acute lung injury (ALI) model in Sprague-Dawley rats, which was similar to ARDS in humans, using intratracheal administration of lipopolysaccharide (LPS). The intraperitoneal administration of paeonol successfully reduced histopathological scores and attenuated myeloperoxidase-reactive cells as an index of polymorphonuclear neutrophils infiltration and also reduces inducible nitric oxide synthase expression in the lung tissue, at 16?h after LPS administration. In addition, paeonol reduced proinflammatory cytokines in bronchoalveolar lavage fluid, including tumor-necrosis factor-?, interleukin-1?, interleukin-6, and plasminogen-activated inhibition factor-1. These results indicated that paeonol successfully attenuates inflammatory and coagulation reactions to protect against ALI. PMID:22454687

Fu, Pin-Kuei; Wu, Chieh-Liang; Tsai, Tung-Hu; Hsieh, Ching-Liang

2012-01-01

125

Pre-Treatment of Recombinant Mouse MFG-E8 Downregulates LPS-Induced TNF-? Production in Macrophages via STAT3-Mediated SOCS3 Activation  

PubMed Central

Milk fat globule-epidermal growth factor factor 8 (MFG-E8) regulates innate immune function by modulating cellular signaling, which is less understood. Herein, we aimed to investigate the direct anti-inflammatory role of MFG-E8 in macrophages by pre-treatment with recombinant murine MFG-E8 (rmMFG-E8) followed by stimulation with LPS in RAW264.7 cells and in peritoneal macrophages, isolated from wild-type (WT) or MFG-E8?/? mice. RAW264.7 cells and mouse peritoneal macrophages treated with rmMFG-E8 significantly downregulated LPS-induced TNF-? mRNA by 25% and 24%, and protein levels by 29% and 23%, respectively (P<0.05). Conversely, peritoneal macrophages isolated from MFG-E8?/? mice produced 28% higher levels of TNF-?, as compared to WT mice when treated with LPS. In in vivo, endotoxemia induced by intraperitoneal injection of LPS (5 mg/kg BW), at 4 h after induction, serum level of TNF-? was significantly higher in MFG-E8?/? mice (837 pg/mL) than that of WT (570 pg/mL, P<0.05). To elucidate the direct anti-inflammatory effect of MFG-E8, we examined STAT3 and its target gene, SOCS3. Treatment with rmMGF-E8 significantly induced pSTAT3 and SOCS3 in macrophages. Similar results were observed in in vivo treatment of rmMFG-E8 in peritoneal cells and splenic tissues. Pre-treatment with rmMFG-E8 significantly reduced LPS-induced NF-?B p65 contents. These data clearly indicated that rmMFG-E8 upregulated SOCS3 which in turn interacted with NF-?B p65, facilitating negative regulation of TLR4 signaling for LPS-induced TNF-? production. Our findings strongly suggest that MFG-E8 is a direct anti-inflammatory molecule, and that it could be developed as a therapy in attenuating inflammation and tissue injury. PMID:22114683

Aziz, Monowar; Jacob, Asha; Matsuda, Akihisa; Wu, Rongqian; Zhou, Mian; Dong, Weifeng; Yang, Weng-Lang; Wang, Ping

2011-01-01

126

Delphinidin Inhibits LPS-Induced MUC8 and MUC5B Expression Through Toll-like Receptor 4-Mediated ERK1/2 and p38 MAPK in Human Airway Epithelial Cells  

PubMed Central

Objectives Delphinidin is one of the anthocyanidins. It is believed to have anti-inflammatory property including antioxidant, antiangiogenic, and anti-cancer properties. However, the anti-inflammatory effect of delphinidin in mucin-producing human airway epithelial cells has not been determined. Therefore, this study was conducted in order to investigate the effect and the brief signaling pathway of delphinidin in lipopolysaccharide (LPS)-induced MUC8 and MUC5B expression in human airway epithelial cells. Methods In mucin-producing human NCI-H292 airway epithelial cells and primary cultures of normal nasal epithelial cells, the reverse transcriptase-polymerase chain reaction (RT-PCR), real-time PCR, enzyme immunoassay were used for investigating the expressions of MUC8, MUC5, and Toll-like receptor 4 (TLR4), after LPS treatment and delphinidin treatment. And the signaling pathway of delphinidin on LPS-induced MUC8 and MUC5B expression was investigated using the RT-PCR, and immunoblot analysis. To confirm the involvement of TLR4 in LPS-induced MUC8 and MU5B expression, the cells were transfected with TLR4 siRNA. Results In NCI-H292 airway epithelial cells, LPS (100 ng/mL) significantly induced TLR4, MUC8, and MUC5B expression. TLR4 siRNA significantly blocked LPS-induced MUC8 and MUC5B mRNA expression. LPS (100 ng/mL) significantly activated the phosphorylation of extracellular signal related kinase (ERK) 1/2 and p38 mitogen-activated protein kinase (MAPK). Delphinidin (50 and 100 µM) inhibited LPS-induced TLR4, MUC8, and MUC5B expression and LPS-induced phosphorylation of ERK1/2 and p38 MAPK. In the primary cultures of normal nasal epithelial cells, delphinidin (50 and 100 µM) significantly inhibited LPS-induced TLR4, MUC8, and MUC5B gene expression. Conclusion These results suggest that delphinidin attenuates LPS-induced MUC8 and MUC5B expression through the TLR4-mediated ERK1/2 and p38 MAPK signaling pathway in human airway epithelial cells. These findings indicated that delphinidin may be a therapeutic agent for control of inflammatory airway diseases. PMID:25177436

Bae, Chang Hoon; Jeon, Bo Sung; Choi, Yoon Seok; Song, Si-Youn

2014-01-01

127

Chitosan oligosaccharides suppress production of nitric oxide in lipopolysaccharide-induced N9 murine microglial cells in vitro.  

PubMed

Chitosan oligosaccharides (COS) have been reported to exert many biological activities, such as antioxidant, antitumor and anti-inflammatory effects. In the present study, we examined the effect of COS on nitric oxide (NO) production in LPS induced N9 microglial cells. Pretreatment with COS (50~200 ?g/ml) could markedly inhibit NO production by suppressing inducible nitric oxide synthase (iNOS) expression in activated microglial cells. Signal transduction studies showed that COS remarkably inhibited LPS-induced phosphorylation of p38 MAPK and ERK1/2. COS pretreatment could also inhibit the activation of both nuclear factor-?B (NF-?B) and activator protein-1 (AP-1). In conclusion, our results suggest that COS could suppress the production of NO in LPS-induced N9 microglial cells, mediated by p38 MAPK and ERK1/2 pathways. PMID:22623214

Wei, Peng; Ma, Pan; Xu, Qing-Song; Bai, Qun-Hua; Gu, Jian-Guo; Xi, Hao; Du, Yu-Guang; Yu, Chao

2012-08-01

128

Propofol pretreatment attenuates LPS-induced granulocyte-macrophage colony-stimulating factor production in cultured hepatocytes by suppressing MAPK/ERK activity and NF-{kappa}B translocation  

SciTech Connect

Propofol (PPF), a widely used intravenous anesthetic for induction and maintenance of anesthesia during surgeries, was found to possess suppressive effect on host immunity. This study aimed at investigating whether PPF plays a modulatory role in the lipopolysaccharide (LPS)-induced inflammatory cytokine expression in a cell line of rat hepatocytes. Morphological observation and viability assay showed that PPF exhibits no cytotoxicity at concentrations up to 300 {mu}M after 48 h incubation. Pretreatment with 100 {mu}M PPF for 24 h prior to LPS stimulation was performed to investigate the modulatory effect on LPS-induced inflammatory gene production. The results of semi-quantitative RT-PCR demonstrated that PPF pretreatment significantly suppressed the LPS-induced toll-like receptor (TLR)-4, CD14, tumor necrosis factor (TNF)-{alpha}, and granulocyte-macrophage colony-stimulating factor (GM-CSF) gene expression. Western blotting analysis showed that PPF pretreatment potentiated the LPS-induced TLR-4 downregulation. Flow cytometrical analysis revealed that PPF pretreatment showed no modulatory effect on the LPS-upregulated CD14 expression on hepatocytes. In addition, PPF pretreatment attenuated the phosphorylation of mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) and I{kappa}B{alpha}, as well as the nuclear translocation of NF-{kappa}B primed by LPS. Moreover, addition of PD98059, a MAPK kinase inhibitor, significantly suppressed the LPS-induced NF-{kappa}B nuclear translocation and GM-CSF production, suggesting that the PPF-attenuated GM-CSF production in hepatocytes may be attributed to its suppressive effect on MAPK/ERK signaling pathway. In conclusion, PPF as an anesthetic may clinically benefit those patients who are vulnerable to sepsis by alleviating sepsis-related inflammatory response in livers.

Jawan, Bruno [Department of Anesthesiology and Liver Transplantation Program, Chang Gung Memorial Hospital, Kaohsiung Medical Center, Chang Gung University College of Medicine, 123 Ta-Pei Road, Niao-Sung Hsiang, Kaohsiung Hsien 833, Taiwan (China); Kao, Y.-H. [Department of Anesthesiology and Liver Transplantation Program, Chang Gung Memorial Hospital, Kaohsiung Medical Center, Chang Gung University College of Medicine, 123 Ta-Pei Road, Niao-Sung Hsiang, Kaohsiung Hsien 833, Taiwan (China); Department of Biological Sciences, National Sun Yat-Sen University, 70 Lien-Hai Road, Kaohsiung 804, Taiwan (China); Goto, Shigeru [Department of Surgery and Liver Transplantation Program, Chang Gung Memorial Hospital, Kaohsiung Medical Center, Chang Gung University College of Medicine, 123 Ta-Pei Road, Niao-Sung Hsiang, Kaohsiung Hsien 833, Taiwan (China); Department of Surgery, Iwao Hospital, 3059-1 Kawakami, Yufuin, Oita 879-5102 (Japan); Pan, M.-C. [Department of Anesthesiology and Liver Transplantation Program, Chang Gung Memorial Hospital, Kaohsiung Medical Center, Chang Gung University College of Medicine, 123 Ta-Pei Road, Niao-Sung Hsiang, Kaohsiung Hsien 833, Taiwan (China); Lin, Y.-C.; Hsu, L.-W.; Nakano, Toshiaki; Lai, C.-Y.; Sun, C.-K.; Cheng, Y.-F. [Department of Surgery and Liver Transplantation Program, Chang Gung Memorial Hospital, Kaohsiung Medical Center, Chang Gung University College of Medicine, 123 Ta-Pei Road, Niao-Sung Hsiang, Kaohsiung Hsien 833, Taiwan (China); Tai, M.-H. [Department of Biological Sciences, National Sun Yat-Sen University, 70 Lien-Hai Road, Kaohsiung 804, Taiwan (China); Department of Medical Research and Education, Kaohsiung Veterans General Hospital, 386 Ta-Chung 1st Road, Kaohsiung 813, Taiwan (China)] (and others)

2008-06-15

129

Monocyte B7 and Sialyl Lewis X modulates the efficacy of IL-10 down-regulation of LPS-induced monocyte tissue factor in whole blood.  

PubMed

Recent studies have investigated the use of anti-inflammatory cytokine, interleukin 10 (IL-10) to control the development of disseminated intravascular coagulation (DIC) in sepsis by down-regulation of monocyte tissue factor (MTF) induced by lipopolysaccharide (LPS) in the initial phase of the disease. In vitro and in vivo human studies have shown that a minimal (<1 h) delay in IL-10 treatment significantly reduces the cytokines ability to inhibit LPS-induced MTF expression and the end products of coagulation. In this whole blood in vitro study we investigated the role of lymphocyte and platelet interactions with monocytes to up-regulate MTF expression in the presence of IL-10 in the initial phase of exposure to LPS. Individual blockade of monocyte B7 or platelet P-selectin significantly (35%) reduced MTF expression (P<0.05). IL-10 showed a dose-dependent inhibition of LPS (0.1 microg/ml) induced MTF expression, with 56% inhibition at 1 ng/ml, maximizing at 5 ng/ml IL-10 (75%; P<0.05). Simultaneous exposure to LPS and IL-10 (1 ng/ml) or addition of IL-10 1 h after LPS, with individual B7 and P-selectin blockade significantly enhanced the inhibition of MTF expression by IL-10 (P<0.05). We conclude that the efficacy of IL-10 to control DIC could be enhanced by a simultaneous B7 and P-selectin blockade. PMID:9695978

Warnes, G; Biggerstaff, J P; Francis, J L

1998-07-01

130

A heteroglycan from the cyanobacterium Nostoc commune modulates LPS-induced inflammatory cytokine secretion by THP-1 monocytes through phosphorylation of ERK1/2 and Akt.  

PubMed

Cyanobacteria (blue-green algae) have been consumed as food and used in folk medicine since ancient times to alleviate a variety of diseases. Cyanobacteria of the genus Nostoc have been shown to produce complex exopolysaccharides with antioxidant and antiviral activity. Furthermore, Nostoc sp. are common in cyanolichen symbiosis and lichen polysaccharides are known to have immunomodulating effects. Nc-5-s is a heteroglycan isolated from free-living colonies of Nostoc commune and its structure has been characterized in detail. The aim of this study was to determine the effects of Nc-5-s on the inflammatory response of lipopolysaccharide (LPS)-stimulated human THP-1 monocytes and how the effects are mediated. THP-1 monocytes primed with interferon-? and stimulated with LPS in the presence of Nc-5-s secreted less of the pro-inflammatory cytokine interleukin (IL)-6 and more of the anti-inflammatory cytokine IL-10 than THP-1 monocytes stimulated without Nc-5-s. In contrast, Nc-5-s increased LPS-induced secretion of the pro-inflammatory cytokines tumor necrosis factor (TNF)-? and IL-8. Nc-5-s decreased LPS-induced phosphorylation of the extracellular regulated kinase (ERK)1/2 and Akt kinase, but did not affect phosphorylation of the p38 kinase, activation of the nuclear factor kappa B pathway, nor DNA binding of c-fos. These results show that Nc-5-s has anti-inflammatory effects on IL-6 and IL-10 secretion by THP-1 monocytes, but its effects are pro-inflammatory when it comes to TNF-? and IL-8. Furthermore, they show that the effects of Nc-5-s may be mediated through the ERK1/2 pathway and/or the Akt/phosphoinositide 3-kinase pathway and their downstream effectors. The ability of Nc-5-s to decrease IL-6 secretion, increase IL-10 secretion and moderate ERK1/2 activation indicates a potential for its development as an anti-inflammatory agent. PMID:24877713

Olafsdottir, Astridur; Thorlacius, Gudny Ella; Omarsdottir, Sesselja; Olafsdottir, Elin Soffia; Vikingsson, Arnor; Freysdottir, Jona; Hardardottir, Ingibjorg

2014-09-25

131

Ginsenoside Rh2 Downregulates LPS-Induced NF-?B Activation through Inhibition of TAK1 Phosphorylation in RAW 264.7 Murine Macrophage  

PubMed Central

The present study was carried out to evaluate the inhibitory effects of ginsenoside Rh2 on nuclear-factor- (NF-) ?B in lipopolysaccharide- (LPS-) activated RAW 264.7 murine macrophages. RAW 264.7 cells were pretreated with indicated concentrations of ginsenoside Rh2 for 1?h prior to the incubation of LPS (1??g/mL) for indicated time period. Ginsenoside Rh2 reduced CD14 and Toll-like receptor 4 (TLR4) expressions 24?h after LPS stimulation. Furthermore, ginsenoside Rh2 significantly inhibited TGF-beta-activated kinase 1 (TAK1) phosphorylation 30?min after LPS stimulation. Ginsenoside Rh2 was further shown to inhibit NF-?B p65 translocation into the nucleus by suppressing I?B-? degradation. Also, LPS increased mRNA expression of TNF-? and IL-1? time-dependently, while TQ reduced TNF-? within 3?h and IL-1? within 1?h. And we firstly found that pretreatment of ginsenoside Rh2 successively inhibited hypoxia-inducible factor- (HIF-) 1? expression increased by LPS. In conclusion, ginsenoside Rh2 may inhibit LPS-induced NF-?B activation and reduce HIF-1? accumulation, suggesting that ginsenoside Rh2 may be considered as a potential therapeutic candidate for chronic inflammatory diseases. PMID:23483870

Lian, Li-Hua; Jin, Quan; Song, Shun-Zong; Wu, Yan-Ling; Bai, Ting; Jiang, Shuang; Li, Qian; Yang, Ning; Nan, Ji-Xing

2013-01-01

132

Berberine inhibits cytosolic phospholipase A2 and protects against LPS-induced lung injury and lethality independent of the alpha2-adrenergic receptor in mice.  

PubMed

Acute lung injury is still a significant clinical problem having a high mortality rate despite significant advances in antimicrobial therapy and supportive care made in the past few years. Our previous study demonstrated that berberine (Ber) remarkably decreased mortality and attenuated the lung injury in mice challenged with LPS, but the mechanism behind this remains unclear. Here, we report that pretreatment with Ber significantly reduced pulmonary edema, neutrophil infiltration, and histopathological alterations; inhibited protein expression and phosphorylation of cytosolic phospholipase A2; and decreased thromboxane A2 release induced by LPS. Yohimbine, an alpha2-adrenergic receptor antagonist, did not antagonize these actions of Ber. Furthermore, pretreatment with Ber decreased TNF-alpha production and mortality in mice challenged with LPS, which were enhanced by yohimbine, and Ber combined with yohimbine also improved survival rate in mice subjected to cecal ligation and puncture. Taken together, these observations indicate that Ber attenuates LPS-induced lung injury by inhibiting TNF-alpha production and cytosolic phospholipase A2 expression and activation in an alpha2-adrenoceptor-independent manner. Berberine combined with yohimbine might provide an effective therapeutic approach to acute lung injury during sepsis. PMID:18414236

Zhang, Hao-qing; Wang, Hua-dong; Lu, Da-xiang; Qi, Ren-bin; Wang, Yan-ping; Yan, Yu-xia; Fu, Yong-mei

2008-05-01

133

Resveratrol activates AMPK and suppresses LPS-induced NF-?B-dependent COX-2 activation in RAW 264.7 macrophage cells  

PubMed Central

AMP-activated protein kinase (AMPK), an enzyme involved in energy homeostasis, regulates inflammatory responses, but its precise mechanisms are not fully understood. Recent evidence has shown that resveratrol (RES), an AMPK activator, reduces prostaglandin E2 production in lipopolysaccharide (LPS)-treated microglia. Here, we examined the effect of RES on nuclear factor kappa B (NF-?B) dependent cyclooxygenase (COX)-2 activation in LPS-treated RWA 264.7 macrophages. We found that treatment with RES increased AMPK activation. AMPK and acetyl CoA carboxylase phosphorylation were attenuated in cells treated with LPS+RES, compared to cells treated with LPS alone. RES inhibited tumor necrosis factor (TNF)-? and TNF receptor 1 in LPS-treated cells. Finally, RES inhibited LPS-induced NF-?B translocation into the nucleus and COX-2 expression. Moreover, the effects of 5-aminoimidazole-4-carboxamide ribose and compound C were consistent with the effects of RES in LPS-treated cells. Taken together, these results suggest that the anti-inflammatory action of RES in RAW 264.7 macrophages is dependent on AMPK activation and is associated with inhibition of the LPS-stimulated NF-?B-dependent COX-2 signaling pathway. PMID:22025971

Yi, Chin-Ok; Jeon, Byeong Tak; Shin, Hyun Joo; Jeong, Eun Ae; Chang, Ki Churl; Lee, Jung Eun; Lee, Dong Hoon; Kim, Hyun Joon; Kang, Sang Soo; Cho, Gyeong Jae; Choi, Wan Sung

2011-01-01

134

Flavonoid Fraction of Bergamot Juice Reduces LPS-Induced Inflammatory Response through SIRT1-Mediated NF-?B Inhibition in THP-1 Monocytes  

PubMed Central

Plant polyphenols exert anti-inflammatory activity through both anti-oxidant effects and modulation of pivotal pro-inflammatory genes. Recently, Citrus bergamia has been studied as a natural source of bioactive molecules with antioxidant activity, but few studies have focused on molecular mechanisms underlying their potential beneficial effects. Several findings have suggested that polyphenols could influence cellular function by acting as activators of SIRT1, a nuclear histone deacetylase, involved in the inhibition of NF-?B signaling. On the basis of these observations we studied the anti-inflammatory effects produced by the flavonoid fraction of the bergamot juice (BJe) in a model of LPS-stimulated THP-1 cell line, focusing on SIRT1-mediated NF-?B inhibition. We demonstrated that BJe inhibited both gene expression and secretion of LPS-induced pro-inflammatory cytokines (IL-6, IL-1?, TNF-?) by a mechanism involving the inhibition of NF-?B activation. In addition, we showed that BJe treatment reversed the LPS-enhanced acetylation of p65 in THP-1 cells. Interestingly, increasing concentrations of Sirtinol were able to suppress the inhibitory effect of BJe via p65 acetylation, underscoring that NF-?B–mediated inflammatory cytokine production may be directly linked to SIRT1 activity. These results suggest that BJe may be useful for the development of alternative pharmacological strategies aimed at reducing the inflammatory process. PMID:25260046

Risitano, Roberto; Currò, Monica; Cirmi, Santa; Ferlazzo, Nadia; Campiglia, Pietro; Caccamo, Daniela; Ientile, Riccardo; Navarra, Michele

2014-01-01

135

Chebulagic acid (CA) attenuates LPS-induced inflammation by suppressing NF-{kappa}B and MAPK activation in RAW 264.7 macrophages  

SciTech Connect

Chebulagic acid (CA), a natural anti-oxidant, showed potent anti-inflammatory effects in LPS-stimulated RAW 264.7, a mouse macrophage cell line. These effects were exerted via inhibition of NO and PGE{sub 2} production and down-regulation of iNOS, COX-2, 5-LOX, TNF-{alpha} and IL-6. CA inhibited NF-{kappa}B activation by LPS, and this was associated with the abrogation of I{kappa}B-{alpha} phosphorylation and subsequent decreases in nuclear p50 and p65 protein levels. Further, the phosphorylation of p38, ERK 1/2 and JNK in LPS-stimulated RAW 264.7 cells was suppressed by CA in a concentration-dependent manner. LPS-induced generation of reactive oxygen species (ROS) was also effectively inhibited by CA. These results suggest that CA exerts anti-inflammatory effects in LPS-stimulated RAW 264.7 macrophages by inhibition of NF-{kappa}B activation and MAP kinase phosphorylation.

Reddy, D. Bharat [Department of Animal Sciences, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad 500046 (India); Reddanna, Pallu [Department of Animal Sciences, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad 500046 (India)], E-mail: preddanna@yahoo.com

2009-03-27

136

INVOLVEMENT OF TOLL-LIKE RECEPTOR 4 AND MAPK PATHWAYS IN LPS-INDUCED CD40 EXPRESSION IN MONOCYTIC CELLS  

EPA Science Inventory

CD40 is a co-stimulatory surface molecule actively expressed on mature dendritic cells (DC). Recent studies suggest that endotoxin (LPS) inhalation induces DC maturation in the airways of healthy volunteers. To characterize the effect of LPS on CD40 expression and underlying mech...

137

Role of p38 MAPK in LPS induced pro-inflammatory cytokine and chemokine gene expression in equine leukocytes  

Microsoft Academic Search

Endotoxemia occurs when bacterial lipopolysaccharide (LPS) in the blood induces a dysregulated inflammatory response, resulting in circulatory shock and multi-organ failure. Laminitis is a common complication in endotoxemic horses and is frequently the reason for humane euthanasia of these cases. Blood leukocytes are a principal target of LPS in endotoxemia leading to activation of multiple signal transduction pathways involved in

Laura E. Neuder; Jamie M. Keener; Rachael E. Eckert; Jennifer C. Trujillo; Samuel L. Jones

2009-01-01

138

Role of p38 MAPK in LPS induced pro-inflammatory cytokine and chemokine gene expression in equine leukocytes.  

PubMed

Endotoxemia occurs when bacterial lipopolysaccharide (LPS) in the blood induces a dysregulated inflammatory response, resulting in circulatory shock and multi-organ failure. Laminitis is a common complication in endotoxemic horses and is frequently the reason for humane euthanasia of these cases. Blood leukocytes are a principal target of LPS in endotoxemia leading to activation of multiple signal transduction pathways involved in the induction of a number of pro-inflammatory genes. In other animal models, the p38 mitogen activated protein kinase (MAPK) pathway has been associated with induced expression of tumor necrosis factor-alpha (TNFalpha), interleukin (IL)-1beta, IL-6 and IL-8. The goal of this study was to determine the role of the p38 MAPK pathway in the induction of these pro-inflammatory cytokine and chemokine genes in LPS-stimulated equine leukocytes. Stimulation of equine peripheral blood leukocytes resulted in an increase in TNFalpha, IL-1beta, IL-6 and IL-8 mRNA levels. Pharmacological inhibition of p38 MAPK activity with SB203580 or SB202190 reduced the ability of LPS stimulation to increase mRNA concentrations for all four genes. However, only SB203580 pretreatment significantly reduced LPS-stimulated IL-1beta and IL-8 mRNA expression and only pretreatment with SB202190 significantly reduced LPS-stimulated TNFalpha and IL-6 mRNA expression. From this study we conclude TNFalpha, IL-1beta, IL-6 and IL-8 are induced upon LPS stimulation of equine leukocytes and that this induction of gene expression is dependent on the p38 MAPK pathway. However, there are differences in the efficacy of the p38 inhibitors tested here that may be explained by differences in specificity or potency. This study provides evidence for the use of selective p38 MAPK inhibitors as potential therapeutics for the treatment of equine endotoxemia. PMID:19070370

Neuder, Laura E; Keener, Jamie M; Eckert, Rachael E; Trujillo, Jennifer C; Jones, Samuel L

2009-06-15

139

Identification of a LPS-induced TNF-? factor (LITAF) from mollusk Solen grandis and its expression pattern towards PAMPs stimulation.  

PubMed

Lipopolysaccharide-induced TNF-? factor (LITAF) is one of the most important transcription factors mediating TNF-? transcription. In the present study, a LITAF gene (designated as SgLITAF) was identified from razor clams Solen grandis. The full-length cDNA of SgLITAF was of 1476 bp, encoding a polypeptide of 130 amino acids showed high similarity to other known LITAFs. SgLITAF encoded a LITAF domain and the Zn(2+)-binding motifs in the domain were well conserved. The mRNA transcripts of SgLITAF were detected in all tested tissues of healthy razor clams, including mantle, gill, gonad, hemocytes, muscle and hepatopancreas, and with the highest expression level in hepatopancreas. The expression level of SgLITAF in hemocytes was significantly up-regulated (P < 0.01) after razor clams were stimulated by LPS or ?-1, 3-glucan, but no obvious fluctuation of SgLITAF mRNA expression was observed after PGN stimulation. All the results indicated that there might be a LITAF-regulated TNF-? signaling pathway existing in S. grandis, which involved in the immune response not only against gram-negative bacteria but also towards fungi. PMID:23891855

Yang, Dinglong; Wei, Xiumei; Yang, Jianmin; Yang, Jialong; Xu, Jie; Fang, Jinghui; Wang, Sheng; Liu, Xiangquan

2013-10-01

140

A molecular pharmacology study into the anti-inflammatory actions of Euphorbia hirta L. on the LPS-induced RAW 264.7 cells through selective iNOS protein inhibition.  

PubMed

Euphorbia hirta L. has been widely used in India and Chinese society. The molecular pharmacology basis of its anti-inflammatory effect is revealed in this work. The ethanol extract of Euphorbia hirta L. (Eh) and its active component were studied in lipopolysaccharide (LPS)-activated macrophage cells (RAW 264.7) as an established inflammation model. After activation, nitric oxide (NO) production and expression of iNOS protein and iNOS mRNA were measured by using a colorimetric assay (Griess reagent), western blotting, and reverse transcription polymerase chain reaction (RT-PCR), respectively. The alteration in the content of PGE(2), TNFalpha, and IL-6 was concurrently monitored by ELISA. In results, we found that in the concentration range without showing cytotoxicity, Eh produced a remarkable anti-inflammatory effect via its active component of beta-amyrin and showed a dose-related inhibition of LPS-induced NO production. This phenomenon is in accordance with a substantial inhibition of iNOS protein. However, the expression of iNOS gene was unaffected by Eh treatments. Compared with indomethacin, Eh has much more potency and a specific action of NO inhibition but Eh works less specifically on PGE(2), IL-6, and TNF-alpha inhibition. The extract of Euphorbia hirta L. and its component beta-amyrin are able to block most of the iNOS protein functions and NO induction, and could therefore be new selective NO inhibitors with great potential in treating arthritis inflammation. PMID:20390370

Shih, Mei-Fen; Cheng, Yih-Dih; Shen, Chia-Rui; Cherng, Jong-Yuh

2010-07-01

141

Insights into the inhibition and mechanism of compounds against LPS-induced PGE2 production: a pathway network-based approach and molecular dynamics simulations.  

PubMed

In comparison to the current target-based screening approach, it is increasingly evident that active lead compounds based on disease-related phenotypes are more likely to be translated to clinical trials during drug development. That is, because human diseases are in essence the outcome of the abnormal function of multiple genes, especially in complex diseases. Therefore, as a conventional technology in the early phase of active lead compound discovery, computational methods that can connect molecular interactions and disease-related phenotypes to evaluate the efficacy of compounds are in urgently required. In this work, a computational approach that integrates molecular docking and pathway network analysis (network efficiency and network flux) was developed to evaluate the efficacy of a compound against LPS-induced Prostaglandin E2(PGE2) production. The predicted results were then validated in vitro, and a correlation with the experimental results was analyzed using linear regression. In addition, molecular dynamics (MD) simulations were performed to explore the molecular mechanism of the most potent compounds. There were 12 hits out of 28 predicted ingredients separated from Reduning injection (RDN). The predicted results have a good agreement with the experimental inhibitory potency (IC50) (correlation coefficient = 0.80). The most potent compounds could target several proteins to regulate the pathway network. This might partly interpret the molecular mechanism of RDN on fever. Meanwhile, the good correlation of the computational model with the wet experimental results might bridge the gap between molecule-target interactions and phenotypic response, especially for multi-target compounds. Therefore, it would be helpful for active lead compound discovery, the understanding of the multiple targets and synergic essence of traditional Chinese medicine (TCM). PMID:25228393

Zhang, Xinzhuang; Gu, Jiangyong; Cao, Liang; Ma, Yimin; Su, Zhenzhen; Luo, Fang; Wang, Zhenzhong; Li, Na; Yuan, Gu; Chen, Lirong; Xu, Xiaojie; Xiao, Wei

2014-12-18

142

Apolipoprotein A-I inhibits LPS-induced atherosclerosis in ApoE?/? mice possibly via activated STAT3-mediated upregulation of tristetraprolin  

PubMed Central

Aim: To investigate the effects of the major component of high-density lipoprotein apolipoprotein A-I (apoA-I) on the development of atherosclerosis in LPS-challenged ApoE?/? mice and the underlying mechanisms. Methods: Male ApoE-KO mice were daily injected with LPS (25 ?g, sc) or PBS for 4 weeks. The LPS-challenged mice were intravenously injected with rAAV-apoA-I-GFP or rAAV-GFP. After the animals were killed, blood, livers and aortas were collected for biochemical and histological analyses. For ex vivo experiments, the abdominal cavity macrophages were harvested from each treatment group of mice, and cultured with autologous serum, then treated with LPS. Results: Chronic administration of LPS in ApoE?/? mice significantly increased the expression of inflammatory cytokines (TNF-?, IL-1?, IL-6, and MCP-1), increased infiltration of inflammatory cells, and enhanced the development of atherosclerosis. In LPS-challenged mice injected with rAAV-apoA-I-GFP, viral particles and human apoA-I were detected in the livers, total plasma human apoA-I levels were grammatically increased; HDL-cholesterol level was significantly increased, TG and TC were slightly increased. Furthermore, overexpression of apoA-I significantly suppressed the expression of proinflammatory cytokines, reduced the infiltration of inflammatory cells, and decreased the extent of atherosclerotic lesions. Moreover, overexpression of apoA-I significantly increased the expression of the cytokine mRNA-destabilizing protein tristetraprolin (TTP), and phosphorylation of JAK2 and STAT3 in aortas. In ex vivo mouse macrophages, the serum from mice overexpressing apoA-I significantly increased the expression of TTP, accompanied by accelerated decay of mRNAs of the inflammatory cytokines. Conclusion: ApoA-I potently suppresses LPS-induced atherosclerosis by inhibiting the inflammatory response possibly via activation of STAT3 and upregulation of TTP. PMID:23564081

Yin, Kai; Tang, Shi-lin; Yu, Xiao-hua; Tu, Guang-hui; He, Rong-fang; Li, Jin-feng; Xie, Di; Gui, Qing-jun; Fu, Yu-chang; Jiang, Zhi-sheng; Tu, Jian; Tang, Chao-ke

2013-01-01

143

Polygonum cuspidatum, compared with baicalin and berberine, inhibits inducible nitric oxide synthase and cyclooxygenase-2 gene expressions in RAW 264.7 macrophages.  

PubMed

Polygonum cuspidatum water extract (PCWE) was shown to be a potent inhibitor of lipopolysaccharide (LPS)-induced expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). PCWE was compared to baicalin isolated from Scutellaria baicalensis Georgi and berberine of Coptidis rhizoma and Phellodendri cortex, for their effects on LPS-induced nitric oxide (NO) production and iNOS and COX-2 gene expressions in RAW 264.7 macrophages. Both PCWE and the compounds inhibited LPS-induced NO production in a concentration-dependent manner without a cytotoxicity. The decrease in NO production was in parallel with the inhibition of LPS-induced iNOS gene expression by PCWE and the compounds. In contrast, iNOS enzyme activity was not inhibited by PCWE and two agents. In addition, only PCWE inhibited LPS-induced prostaglandin E2 (PGE2) production and COX-2 gene expression without affecting COX-2 enzyme activity, while baicalin or berberine did not. Furthermore, N-nitro-L-arginine (NLA) and N-nitro-L-arginine methyl ester (L-NAME) pretreatment enhanced LPS-induced iNOS protein expression, which was inhibited by these PCWE and two agents, although LPS-induced COX-2 protein expression was not affected by NLA and L-NAME. PCWE inhibited PGE2 production and COX-2 protein expression in NLA/LPS or L-NAME/LPS-co-treated RAW 264.7 cell, however, baicalin or berberine did not. From the results, it was concluded that co-treatment with NOS inhibitors and PCWE effectively blocks acute production of NO and inhibits expression of iNOS and COX-2 genes. PMID:17553752

Kim, Kyung-Woon; Ha, Ki-Tai; Park, Cheol-Soo; Jin, Un-Ho; Chang, Hyen Wook; Lee, In-Seon; Kim, Cheorl-Ho

2007-01-01

144

LPS-induced NF-{kappa}B expression in THP-1Blue cells correlates with neopterin production and activity of indoleamine 2,3-dioxygenase  

SciTech Connect

Research highlights: {yields} LPS induces NF-{kappa}B, neopterin formation and tryptophan degradation in THP-1 cells. {yields} Close dose- and time-dependent correlations exist between these biochemical events. {yields} Data provides some evidence for a parallel induction of them upon TLR stimulation. {yields} Results can be of considerable relevance also in vivo. -- Abstract: Neopterin production is induced in human monocyte-derived macrophages and dendritic cells upon stimulation with Th1-type cytokine interferon-{gamma} (IFN-{gamma}). In parallel, IFN-{gamma} induces the tryptophan-(trp)-degrading enzyme indoleamine 2,3-dioxygenase (IDO) and triggers the formation of reactive oxygen species (ROS). Translocation of the signal transduction element nuclear factor-{kappa}B (NF-{kappa}B) is induced by ROS and accelerates the pro-inflammatory response by activation of other pro-inflammatory pathways. Therefore, a close relationship between NF-{kappa}B expression, the production of neopterin and the degradation of trp can be assumed, although this has not been demonstrated so far. In the present in vitro study we compared the influence of lipopolysaccharide (LPS) on NF-{kappa}B activation, neopterin formation and the degradation of trp in THP-1Blue cells, which represent the human myelomonocytic cell line THP-1 stably transfected with an NF-{kappa}B inducible reporter system. In cells stimulated with LPS, a significant induction of NF-{kappa}B was observed, and this was paralleled by an increase of kynureunine (kyn) and neopterin concentrations and a decline of trp. The increase of the kyn to trp quotient indicates accelerated IDO activity. Higher LPS concentrations and longer incubation of cells were associated with higher activities of all three biochemical pathways and significant correlations existed between NF-{kappa}B activation, neopterin release and trp degradation (all p < 0.001). We conclude that there is a parallel induction of NF-{kappa}B, neopterin formation and trp degradation in monocytic THP-1 cells, which is elicited by pro-inflammatory triggers like LPS during innate immune responses.

Schroecksnadel, Sebastian [Division of Biological Chemistry, Innsbruck Medical University, Innsbruck (Austria)] [Division of Biological Chemistry, Innsbruck Medical University, Innsbruck (Austria); Jenny, Marcel [Division of Biological Chemistry, Innsbruck Medical University, Innsbruck (Austria) [Division of Biological Chemistry, Innsbruck Medical University, Innsbruck (Austria); Division of Medical Biochemistry, Biocenter, Innsbruck Medical University, Innsbruck (Austria); Kurz, Katharina [Department of Internal Medicine, Innsbruck Medical University, Innsbruck (Austria)] [Department of Internal Medicine, Innsbruck Medical University, Innsbruck (Austria); Klein, Angela [Division of Medical Biochemistry, Biocenter, Innsbruck Medical University, Innsbruck (Austria)] [Division of Medical Biochemistry, Biocenter, Innsbruck Medical University, Innsbruck (Austria); Ledochowski, Maximilian [Department of Internal Medicine, Innsbruck Medical University, Innsbruck (Austria)] [Department of Internal Medicine, Innsbruck Medical University, Innsbruck (Austria); Uberall, Florian [Division of Medical Biochemistry, Biocenter, Innsbruck Medical University, Innsbruck (Austria)] [Division of Medical Biochemistry, Biocenter, Innsbruck Medical University, Innsbruck (Austria); Fuchs, Dietmar, E-mail: dietmar.fuchs@i-med.ac.at [Division of Biological Chemistry, Innsbruck Medical University, Innsbruck (Austria)] [Division of Biological Chemistry, Innsbruck Medical University, Innsbruck (Austria)

2010-09-03

145

Inhibition of lipopolysaccharide-induced inducible nitric oxide synthase and cyclooxygenase-2 expression by xanthanolides isolated from Xanthium strumarium.  

PubMed

Three sesquiterpenoids, xanthatin (1), xanthinosin (2), and 4-oxo-bedfordia acid (3) were isolated from Xanthium strumarium as inhibitors of nitric oxide synthesis in activated microglia (IC(50) values: 0.47, 11.2, 136.5 microM, respectively). Compounds 1 and 2 suppressed the expression of iNOS and COX-2 and the activity of NF-kappaB through the inhibition of LPS-induced I-kappaB-alpha degradation in microglia. PMID:18276135

Yoon, Jeong Hoon; Lim, Hyo Jin; Lee, Hwa Jin; Kim, Hee-Doo; Jeon, Raok; Ryu, Jae-Ha

2008-03-15

146

The effect of rivastigmine on the LPS-induced suppression of GnRH/LH secretion during the follicular phase of the estrous cycle in ewes.  

PubMed

This study was designed to determine the effect of a potent subcutaneously injected acetylcholinesterase inhibitor, rivastigmine (6mg/animal), on the gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH) release during inflammation induced by an intravenous lipopolysaccharide (LPS) (400ng/kg) injection in ewes during the follicular phase of the estrous cycle. The results are expressed as the mean values from -2 to -0.5h before and +1 to +3h after treatment. Rivastigmine decreased the acetylcholinesterase concentration in the blood plasma from 176.9±9.5 to 99.3±15.1?mol/min/ml. Endotoxin suppressed LH (5.4±0.6ng/ml) and GnRH (4.6±0.4pg/ml) release; however, the rivastigmine injection restored the LH concentration (7.8±0.8ng/ml) to the control value (7.8±0.7ng/ml) and stimulated GnRH release (7.6±0.8pg/ml) compared to the control (5.9±0.4pg/ml). Immune stress decreased expression of the GnRH gene and its receptor (GnRH-R) in the median eminence as well as LH? and GnRH-R in the pituitary. In the case of the GnRH and LH? genes, the suppressive effect of inflammation was negated by rivastigmine. LPS stimulated cortisol and prolactin release (71.1±14.7 and 217.1±8.0ng/ml) compared to the control group (9.0±5.4 and 21.3±3.5ng/ml). Rivastigmine also showed a moderating effect on cortisol and prolactin secretion (43.1±13.1 and 169.7±29.5ng/ml). The present study shows that LPS-induced decreases in GnRH and LH can be reduced by the AChE inhibitor. This action of the AChE inhibitor could result from the suppression of pro-inflammatory cytokine release and the attenuation of the stress response. However, a direct stimulatory effect of ACh on GnRH/LH secretion should also be considered. PMID:23557940

Herman, A P; Krawczy?ska, A; Bochenek, J; Haziak, K; Romanowicz, K; Misztal, T; Antushevich, H; Herman, A; Tomaszewska-Zaremba, D

2013-05-01

147

Overexpression of S100A7 Protects LPS-Induced Mitochondrial Dysfunction and Stimulates IL-6 and IL-8 in HaCaT Cells  

PubMed Central

Background S100A7 (or psoriasin) is distributed in the cytoplasm of keratinocytes of normal human epidermis, and it is overexpressed in many epidermal inflammatory diseases. Lipopolysaccharide (LPS) induces mitochondrial function changes, which play important roles in multiple cellular mechanisms including inflammation. Although S100A7 expression is regulated by various factors in the human epidermis during inflammation, whether S100A7 interacts with mitochondria in keratinocytes is not clear. Objectives Our study was designed to investigate whether S100A7 could prohibit mitochondrial dysfunction and stimulate cytokines in cultured normal HaCaT cells treated with LPS. Results We generated HaCaT cells that constitutively express enhanced green fluorescence protein (EGFP)-S100A7 (S100A7-EGFP) or EGFP alone, as a control. Here, we show that S100A7-EGFP HaCaT cells exhibit an increase in mitochondrial DNA (mtDNA) copy number and mitochondrial membrane potential (MMP). qRT-PCR revealed that expression of three main mitochondrial biogenesis-associated genes was significantly increased: PPAR-coactivator-1alpha (PGC-1?), the mitochondrial transcription factor A (Tfam) and nuclear respiratory factor-1 (NRF1). S100A7 overexpression increased mtDNA content and effectively increased intracellular adenosine 5?-triphosphate (ATP) production, while decreasing reactive oxygen species (ROS) generation. S100A7 overexpression also significantly decreased the expression of Mfn2 and increased DRP1 expression compared with control EGFP cells. S100A7 down-regulated the expression of the autophagy-related proteins Beclin-1 and LC3B. S100A7 also increased expression of IL-6 and IL-8 cytokines. Knockdown of S100A7 decreased MMP and disrupted mitochondrial homeostasis. Conclusions These findings demonstrate that S100A7 stimulates mitochondrial biogenesis and increases mitochondrial function in HaCaT cells treated with LPS; and S100A7 also promotes secretion of IL-6 and IL-8. PMID:24671027

Sun, Wenyan; Zheng, Yan; Lu, Zhuoyang; Cui, Yang; Tian, Qiong; Xiao, Shengxiang; Liu, Feng; Liu, Jiankang

2014-01-01

148

Triterpenoid saponins from the rhizomes of Anemone flaccida and their inhibitory activities on LPS-induced NO production in macrophage RAW264.7 cells.  

PubMed

A new ursane-type triterpenoid saponin, flaccidoside IV (1), and three new oleanane-type triterpenoid saponins, flaccidosides V-VII (2-4), along with 17 known saponins (5-21), were isolated from the rhizomes of Anemone flaccida. The structures of the new triterpenoid saponins were determined based on spectroscopic analyses and chemical methods. All the isolated saponins were tested for their inhibitory activities on lipopolysaccharide-induced nitric oxide production in RAW264.7 macrophages, and several bisdesmosidic oleanane-type triterpenoid saponins (2, 7, and 10) showed significant inhibitory activities, which indicated they had potential anti-inflammatory activities under their noncytotoxic concentrations in vitro. PMID:25236706

Huang, Xiao-Jun; Tang, Jing-Qun; Li, Man-Mei; Liu, Qing; Li, Yao-Lan; Fan, Chun-Lin; Pei, Hong; Zhao, Hui-Nan; Wang, Ying; Ye, Wen-Cai

2014-09-01

149

Ethanol extract of Synurus deltoides (Aiton) Nakai suppresses in vitro LPS-induced cytokine production in RAW 264.7 macrophages and in vivo acute inflammatory symptoms  

PubMed Central

Synurus deltoides (Aiton) Nakai, belonging to the Compositae family, is an edible plant widely distributed in Northeast Asia. In this study, we examined the mechanisms underlying the immunomodulative effects of the ethanol extract of S. deltoides (SDE). The SDE extract strongly down-regulated the mRNA expression of the inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and tumour necrosis factor (TNF)-?, thereby inhibiting the production of nitric oxide (NO), prostaglandin E2 (PGE2), and TNF-? in the lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Furthermore, SDE also suppressed the nuclear translocation of the activation protein (AP)-1 and the nuclear factor-?B (NF-?B), and simultaneously decreased the phosphorylation of extracellular signal-regulated protein kinases (ERK), p38, and Akt. In agreement with the in vitro observations, the orally administered SDE ameliorated the acute inflammatory symptoms in the arachidonic acid-induced ear edema and the EtOH/HCl-induced gastritis in mice. Therefore, S. deltoides have a potential anti-inflammatory capacity in vitro and in vivo, suggesting the potential therapeutic use in the inflammation-associated disorders. PMID:24611100

Jiang, Yunyao

2014-01-01

150

Short-term heating reduces the anti-inflammatory effects of fresh raw garlic extracts on the LPS-induced production of NO and pro-inflammatory cytokines by downregulating allicin activity in RAW 264.7 macrophages.  

PubMed

Garlic has a variety of biologic activities, including anti-inflammatory properties. Although garlic has several biologic activities, some people dislike eating fresh raw garlic because of its strong taste and smell. Therefore, garlic formulations involving heating procedures have been developed. In this study, we investigated whether short-term heating affects the anti-inflammatory properties of garlic. Fresh and heated raw garlic extracts (FRGE and HRGE) were prepared with incubation at 25 °C and 95 °C, respectively, for 2 h. Treatment with FRGE and HRGE significantly reduced the LPS-induced increase in the pro-inflammatory cytokine concentration (TNF-?, IL-1?, and IL-6) and NO through HO-1 upregulation in RAW 264.7 macrophages. The anti-inflammatory effect was greater in FRGE than in HRGE. The allicin concentration was higher in FRGE than in HRGE. Allicin treatment showed reduced production of pro-inflammatory cytokines and NO and increased HO-1 activity. The results show that the decrease in LPS-induced NO and pro-inflammatory cytokines in RAW 264.7 macrophages through HO-1 induction was greater for FRGE compared with HRGE. Additionally, the results indicate that allicin is responsible for the anti-inflammatory effect of FRGE. Our results suggest a potential therapeutic use of allicin in the treatment of chronic inflammatory disease. PMID:23583806

Shin, Jung-Hye; Ryu, Ji Hyeon; Kang, Min Jung; Hwang, Cho Rong; Han, Jaehee; Kang, Dawon

2013-08-01

151

LPS-induced iNOS expression in N9 microglial cells is suppressed by geniposide via ERK, p38 and nuclear factor-?B signaling pathways.  

PubMed

Activated microglia producing reactive nitrogen species, inflammatory factors, reactive oxygen species (ROS) and other neurovirulent factors, can lead to the development of neurodegenerative diseases. Certain compounds can inhibit the activation of microglia. However, the mechanisms remain unclear. In the present study, we investigated the inhibitory effect of geniposide on the production of ROS and inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-stimulated N9 murine microglial cells through the p38, ERK1/2 and nuclear factor-?B (NF-?B) signaling pathways. After the N9 cells were pre-treated with the vehicle or geniposide and exposed to LPS for the time indicated, the MTT conversion test was used to assess cell viability. Suitable concentrations were chosen and adjusted according to the experiments. Extracellular nitric oxide (NO) release was measured by Griess reaction. The formation of ROS and intracellular NO was evaluated by fluorescence imaging. NOS activities were determined using commercially available kits. The morphology of the N9 cells was examined by hematoxylin and eosin staining. The expression of iNOS mRNA was examined by RT-PCR. The protein levels of iNOS, p38 mitogen-activated protein kinase (MAPK), ERK1/2 and NF-?B, inhibitory factor-?B-? (I?B-?) were determined by western blot analysis. The results showed that geniposide attenuated the activation of N9 cells and inhibited the overproduction of NO, intracellular ROS and the expression of iNOS induced by LPS in the cells. In addition, geniposide blocked the phosphorylation of p38, ERK1/2 and inhibited the drop-off of I?B induced by LPS in the cells. These data indicate that geniposide has therapeutic potential for the treatment of neurodegenerative diseases, and that it exerts its effects by inhibiting inflammation. PMID:22710392

Zhang, Gu; He, Jun-Lin; Xie, Xiao-Yan; Yu, Chao

2012-09-01

152

Oryeongsan inhibits LPS-induced production of inflammatory mediators via blockade of the NF-kappaB, MAPK pathways and leads to HO-1 induction in macrophage cells  

PubMed Central

Background Oryeongsan (OR) is an herbal medication used in east-Asian traditional medicine to treat dysuresia, such as urinary frequency, hematuria, and dysuria due to renal disease and chronic nephritis. Recent studies showed that protective effect against acute gastric mucosal injury and an inhibitory effect on the renin-angiotensin-aldosterone pathway of OR. However, its effect on inflammation still remains unknown. In this study, to provide insight into the biological effects of OR, we investigated their effects on lipopolysaccharide (LPS)-mediated inflammation in the RAW 264.7 macrophage cells. Methods We investigated the pharmacological and biological effects of OR on the production of pro-inflammatory cytokines, inflammatory mediators, and related products through Enzyme-linked immunosorbent assay (ELISA), reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis. Also, we examined the activation and suppression of nuclear factor (NF)-kappaB and mitogen-activated protein kinases (MAPKs) pathways in LPS-stimulated macrophages via Western blot analysis in order to explore inhibitory mechanism of OR. Results OR had anti-inflammatory effects by inhibiting the production of nitric oxide (NO), tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and IL-1beta. In addition, it strongly suppressed cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS), NO synthesizing enzymes. It also induced heme oxygenase (HO)-1 expression and inhibited NF-kappaB signaling pathway activation and phosphorylation of MAPKs. Conclusions We further demonstrate the anti-inflammatory effects and inhibitory mechanism of OR in LPS-stimulated macrophages for the first time. OR contains strong anti-inflammatory activity and affects various mechanism pathways including NF-kappaB, MAPKs and HO-1. Our results suggest that OR has potential value to be developed as an inflammatory therapeutic agent from a natural substance. PMID:25023125

2014-01-01

153

Inhibition of LPS-Induced TNF-? and NO Production in Mouse Macrophage and Inflammatory Response in Rat Animal Models by a Novel Ayurvedic Formulation, BV-9238.  

PubMed

Rheumatoid arthritis is a chronic crippling disease, where protein-based tumor necrosis factor-alpha (TNF-?) inhibitors show significant relief, but with potentially fatal side effects. A need for a safe, oral, cost-effective small molecule or phyto-pharmaceutical is warranted. BV-9238 is an Ayurvedic poly-herbal formulation containing specialized standardized extracts of Withania somnifera, Boswellia serrata, Zingiber officinale and Curcuma longa. The anti-inflammatory and anti-arthritic effects of BV-9238 were evaluated for inhibition of TNF-? and nitric oxide (NO) production, in lipopolysaccharide-stimulated, RAW 264.7, mouse macrophage cell line. BV-9238 reduced TNF-? and NO production, without any cytotoxic effects. Subsequently, the formulation was tested in adjuvant-induced arthritis (AIA) and carrageenan-induced paw edema (CPE) rat animal models. AIA was induced in rats by injecting Freund's complete adjuvant intra-dermally in the paw, and BV-9238 and controls were administered orally for 21?days. Arthritic scores in AIA study and inflamed paw volume in CPE study were significantly reduced upon treatment with BV-9238. These results suggest that the anti-inflammatory and anti-arthritic effects of BV-9238 are due to its inhibition of TNF-?, and NO, and this formulation shows promise as an alternate therapy for inflammatory disorders where TNF-? and NO play important roles. Copyright © 2014 John Wiley & Sons, Ltd. PMID:24706581

Dey, Debendranath; Chaskar, Sunetra; Athavale, Nitin; Chitre, Deepa

2014-10-01

154

Extracts of Ficus exasperata leaf inhibit topical and systemic inflammation in rodents and suppress LPS-induced expression of mediators of inflammation in macrophages.  

PubMed

The leaves of Ficus exasperata are mashed and prepared as poultices that are placed on swellings, wounds, and arthritic joints to relieve swelling and pains by the Igede tribal community of Nigeria. The leaf and stalk are also squeezed and used to mitigate itching or inflammation. These claimed benefits inspired this study in which topical and systemic (acute, chronic) anti-inflammatory activities of a methanol/methylene chloride leaf extract of F. exasperata (MFE) were assessed in rodents. Effects of an aqueous leaf extract (AFE) on lipopolysaccharide-induced expression of interleukin-1? (IL-1?), tumor necrosis factor (TNF)-?, and inducible nitric oxide (iNO) were also investigated in murine bone marrow-derived macrophage (BMDM) cultures. Treatment of rats with MFE (200 and 400?mg/kg) led to significant inhibition of acute and chronic inflammation induced by, respectively, agar and formaldehyde in the paws. Topically, pre-application of mice with MFE (5 µg/ear) also significantly inhibited (by up to 21%) ear edema induced by xylene. In vitro, pre-treatment of BMDM with 5-100 µg AFE/ml significantly inhibited IL-1?, TNF?, and iNO production in a dose-related manner. BMDM viability was not significantly affected AFE at concentrations up to 200 µg/ml. Initial studies showed that flavonoids, alkaloids, and terpenoids were the predominant phytoconstituents in each extract. In conclusion, the results of the various investigations indicated that F. exasperata leaf extracts possess anti-inflammatory properties that could underlie the benefits associated with the folklore use of the plant. The results also show that the extracts may be acting through a suppression of mediators of inflammation, such as IL-1?, TNF?, and iNO. PMID:23098056

Nworu, Chukwuemeka S; Nwuke, Henry C; Akah, Peter A; Okoye, Festus B C; Esimone, Charles O

2013-01-01

155

Anti-inflammatory effects of anthocyanins-rich extract from bilberry (Vaccinium myrtillus L.) on croton oil-induced ear edema and Propionibacterium acnes plus LPS-induced liver damage in mice.  

PubMed

Bilberry (Vaccinium myrtillus L.) has been known to play a protective role in human health due to its high anthocyanin content. This study investigated the anti-inflammatory effects of bilberry extract (BE, containing 42.04% anthocyanin) on Propionibacterium acnes (P. acnes) plus lipopolysaccharide (LPS) induced liver injury and croton oil-induced ear edema in mice. Results showed that BE could effectively inhibit croton oil-induced ear edema and liver inflammation provoked by P. acnes plus LPS, as reflected by the reduced plasma alanine aminotransferase and aspartate aminotransferase activities. These findings were confirmed by hepatic pathological examination. Moreover, BE administration markedly suppressed the increase of liver mRNA levels of iNOS, TNF-?, IL-1? and IL-6, and the protein levels of iNOS, TNF-? and NF-?B. In addition, liver malondialdehyde and NO contents were significantly reduced by BE treatment. These results indicated that BE has potent protective effects on acute and immunological inflammation, which might contribute to the study of the anti-inflammatory effects of natural products and healthy food. PMID:24548119

Luo, Hui; Lv, Xiao-Dan; Wang, Guo-En; Li, Yi-Fang; Kurihara, Hiroshi; He, Rong-Rong

2014-08-01

156

Helminth Excreted/Secreted Antigens Repress Expression of LPS-Induced Let-7i but Not miR-146a and miR-155 in Human Dendritic Cells  

PubMed Central

MicroRNAs have emerged as key regulators of immune responses. They influence immune cells' function and probably the outcome of several infections. Currently, it is largely unknown if helminth parasites and their antigens modify host microRNAs expression. The aim of this study was to explore if excreted/secreted antigens of Taenia crassiceps regulate LPS-induced miRNAs expression in human Dendritic Cells. We found that these antigens repressed LPS-let-7i induction but not mir-146a or mir-155 and this correlates with a diminished inflammatory response. This let-7i downregulation in Dendritic Cells constitutes a novel feature of the modulatory activity that helminth-derived antigens exert on their host. PMID:23509825

Terrazas, Luis I.; Sanchez-Munoz, Fausto; Perez-Miranda, Magaly; Mejia-Dominguez, Ana M.; Ledesma-Soto, Yadira; Bojalil, Rafael; Gomez-Garcia, Lorena

2013-01-01

157

Intraislet release of interleukin 1 inhibits beta cell function by inducing beta cell expression of inducible nitric oxide synthase  

PubMed Central

Cytokines, released in and around pancreatic islets during insulitis, have been proposed to participate in beta-cell destruction associated with autoimmune diabetes. In this study we have evaluated the hypothesis that local release of the cytokine interleukin 1 (IL-1) by nonendocrine cells of the islet induce the expression of inducible nitric oxide synthase (iNOS) by beta cells which results in the inhibition of beta cell function. Treatment of rat islets with a combination of tumor necrosis factor (TNF) and lipopolysaccharide (LPS), conditions known to activate macrophages, stimulate the expression of iNOS and the formation of nitrite. Although TNF+LPS induce iNOS expression and inhibit insulin secretion by intact islets, this combination does not induce the expression of iNOS by beta or alpha cells purified by fluorescence activated cell sorting (Facs). In contrast, IL-1 beta induces the expression of iNOS and also inhibits insulin secretion by both intact islets and Facs-purified beta cells, whereas TNF+LPS have no inhibitory effects on insulin secretion by purified beta cells. Evidence suggests that TNF+LPS inhibit insulin secretion from islets by stimulating the release of IL-1 which subsequently induces the expression of iNOS by beta cells. The IL-1 receptor antagonist protein completely prevents TNF+LPS-induced inhibition of insulin secretion and attenuates nitrite formation from islets, and neutralization of IL-1 with antisera specific for IL-1 alpha and IL-1 beta attenuates TNF+LPS-induced nitrite formation by islets. Immunohistochemical localization of iNOS and insulin confirm that TNF+LPS induce the expression of iNOS by islet beta cells, and that a small percentage of noninsulin-containing cells also express iNOS. Local release of IL-1 within islets appears to be required for TNF+LPS-induced inhibition of insulin secretion because TNF+LPS do not stimulate nitrite formation from islets physically separated into individual cells. These findings provide the first evidence that a limited number of nonendocrine cells can release sufficient quantities of IL-1 in islets to induce iNOS expression and inhibit the function of the beta cell, which is selectively destroyed during the development of autoimmune diabetes. PMID:7530759

1995-01-01

158

Anthemis wiedemanniana essential oil prevents LPS-induced production of NO in RAW 264.7 macrophages and exerts antiproliferative and antibacterial activities in vitro  

Microsoft Academic Search

Anthemis wiedemanniana is known in folk medicine for the treatment of microbial infections, cancer and also urinary and pulmonary problems. In this study, the chemical composition of the essential oil from A. wiedemanniana was evaluated and its antibacterial activity was tested against 10 bacterial strains. The oil was also tested for its potentiality to inhibit nitric oxide production in RAW

Filomena Conforti; Federica Menichini; Carmen Formisano; Daniela Rigano; Felice Senatore; Maurizio Bruno; Sergio Rosselli; Sezgin Çelik

2012-01-01

159

Anthemis wiedemanniana essential oil prevents LPS-induced production of NO in RAW 264.7 macrophages and exerts antiproliferative and antibacterial activities in vitro  

Microsoft Academic Search

Anthemis wiedemanniana is known in folk medicine for the treatment of microbial infections, cancer and also urinary and pulmonary problems. In this study, the chemical composition of the essential oil from A. wiedemanniana was evaluated and its antibacterial activity was tested against 10 bacterial strains. The oil was also tested for its potentiality to inhibit nitric oxide production in RAW

Filomena Conforti; Federica Menichini; Carmen Formisano; Daniela Rigano; Felice Senatore; Maurizio Bruno; Sergio Rosselli; Sezgin Çelik

2011-01-01

160

The Effect of PPE-Induced Emphysema and Chronic LPS-Induced Pulmonary Inflammation on Atherosclerosis Development in APOE*3-LEIDEN Mice  

PubMed Central

Background Chronic obstructive pulmonary disease (COPD) is characterized by pulmonary inflammation, airways obstruction and emphysema, and is a risk factor for cardiovascular disease (CVD). However, the contribution of these individual COPD components to this increased risk is unknown. Therefore, the aim of this study was to determine the contribution of emphysema in the presence or absence of pulmonary inflammation to the increased risk of CVD, using a mouse model for atherosclerosis. Because smoke is a known risk factor for both COPD and CVD, emphysema was induced by intratracheal instillation of porcine pancreatic elastase (PPE). Methods Hyperlipidemic APOE*3-Leiden mice were intratracheally instilled with vehicle, 15 or 30 µg PPE and after 4 weeks, mice received a Western-type diet (WTD). To study the effect of emphysema combined with pulmonary inflammation on atherosclerosis, mice received 30 µg PPE and during WTD feeding, mice were intranasally instilled with vehicle or low-dose lipopolysaccharide (LPS; 1 µg/mouse, twice weekly). After 20 weeks WTD, mice were sacrificed and emphysema, pulmonary inflammation and atherosclerosis were analysed. Results Intratracheal PPE administration resulted in a dose-dependent increase in emphysema, whereas atherosclerotic lesion area was not affected by PPE treatment. Additional low-dose intranasal LPS administration induced a low-grade systemic IL-6 response, as compared to vehicle. Combining intratracheal PPE with intranasal LPS instillation significantly increased the number of pulmonary macrophages and neutrophils. Plasma lipids during the study were not different. LPS instillation caused a limited, but significant increase in the atherosclerotic lesion area. This increase was not further enhanced by PPE. Conclusion This study shows for the first time that PPE-induced emphysema both in the presence and absence of pulmonary inflammation does not affect atherosclerotic lesion development. PMID:24303000

Wagenaar, Gerry T. M.; Plomp, Jaap J.; van Eck, Miranda; Havekes, Louis M.; Rensen, Patrick C. N.; Hiemstra, Pieter S.; Berbee, Jimmy F. P.

2013-01-01

161

Inhibition of inducible nitric oxide synthesis by catalposide from Catalpa ovata.  

PubMed

Catalposide (1) and two related iridoids were isolated from the stem of Catalpa ovata (Bignoniaceae) by bioassay guided fractionation. Catalposide (1) significantly inhibited the production of nitric oxide (NO) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages in a dose-dependent manner. RT-PCR and Western blot analyses demonstrated that catalposide (1) suppressed the expression of inducible nitric oxide synthase (iNOS) gene and iNOS protein. Catalposide (1) also inhibited the activation of LPS-induced NF-kappaB as analyzed by electrophoretic mobility shift assay (EMSA). In addition to the inhibitory effect on NO production in LPS-stimulated RAW 264.7 cells, catalposide (1) significantly inhibited the NO production in cytokine-stimulated human DLD-1 and rat vascular smooth muscle (VSM) cells in a dose-dependent manner. PMID:12221588

Oh, Hyuncheol; Pae, Hyun-Ock; Oh, Gi-Su; Lee, Seung Yeob; Chai, Kyu-Yun; Song, Choong Eui; Kwon, Tae-Oh; Chung, Hun-Taeg; Lee, Ho-Sub

2002-08-01

162

Suppression of LPS-induced matrix-metalloproteinase responses in macrophages exposed to phenytoin and its metabolite, 5-(p-hydroxyphenyl-), 5-phenylhydantoin  

Microsoft Academic Search

BACKGROUND: Phenytoin (PHT) has been reported to induce gingival (gum) overgrowth (GO) in approximately 50% of patients taking this medication. While most studies have focused on the effects of PHT on the fibroblast in the pathophysiology underlying GO, few studies have investigated the potential regulatory role of macrophages in extracellular matrix (ECM) turnover and secretion of proinflammatory mediators. The aim

Ryan Serra; Abdel-ghany Al-saidi; Nikola Angelov; Salvador Nares

2010-01-01

163

Sildenafil attenuates LPS-induced pro-inflammatory responses through down-regulation of intracellular ROS-related MAPK/NF-?B signaling pathways in N9 microglia.  

PubMed

Excessive activation of microglial cells has been implicated in various neuroinflammation. The present study showed that sildenafil, a PDE5 inhibitor, significantly suppressed NO, interleukin 1? (IL-1?) and tumor necrosis factor ? (TNF-?) production induced by LPS in microglial cells through decreasing the protein and/or mRNA expressions of inducible NO synthase (iNOS), IL-1? and TNF-? in a concentration-dependent manner. Sildenafil also blocked I?B? phosphorylation and degradation, inhibited the phosphorylation of mitogen-activated protein kinases (MAPKs), extracellular signal-regulated kinases 1 and 2 (ERK1/2), p38 MAPK, and c-Jun N-terminal kinase (JNK). Moreover, the increase of the expression of gp91phox, a critical and catalytic subunit of NADPH oxidase, and the levels of intracellular reactive oxygen species (iROS) induced by LPS were markedly inhibited by sildenafil. In summary, these data suggest that sildenafil exerts its in vitro anti-inflammatory effect in LPS-activated N9 microglial cells by blocking nuclear factor-?B (NF-?B) and MAPKs activation, which may be partly due to its potent down-regulation of the NADPH-derived iROS production. PMID:21220057

Zhao, Siqi; Zhang, Lijia; Lian, Guoning; Wang, Xiaoxiao; Zhang, Haotian; Yao, Xuechun; Yang, Jingyu; Wu, Chunfu

2011-04-01

164

Amelioration of hypoxia and LPS?induced intestinal epithelial barrier dysfunction by emodin through the suppression of the NF??B and HIF?1? signaling pathways.  

PubMed

Intestinal barrier dysfunction occurs in critical illnesses and involves the inflammatory and hypoxic injury of intestinal epithelial cells. Researchers are still defining the underlying mechanisms and evaluating therapeutic strategies for restoring intestinal barrier function. The anti?inflammatory drug, emodin, has been shown to exert a protective effect on intestinal barrier function; however, its mechanisms of action remain unknown. In this study, we investigated the protective effects of emodin on intestinal barrier function and the underlying mechanisms in intestinal epithelial cells challenged with lipopolysaccharide (LPS) and hypoxia/reoxygenation (HR). To induce barrier dysfunction, Caco?2 monolayers were subjected to HR with or without LPS treatment. Transepithelial electrical resistance and paracellular permeability were measured to evaluate barrier function. The expression of the tight junction (TJ) proteins, zonula occludens (ZO)?1, occludin, and claudin?1, as well as that of hypoxia?inducible factor (HIF)?1?, phospho?I?B??, phospho?nuclear factor (NF)??B p65 and cyclooxygenase (COX)?2 was determined by western blot analysis. The results revealed that emodin markedly attenuated the decrease in transepithelial electrical resistance and the increase in paracellular permeability in the Caco?2 monolayers treated with LPS and subjected to HR. Emodin also markedly alleviated the damage caused by LPS and HR (manifested by a decrease in the expression of the TJ protein, ZO?1), and inhibited the expression of HIF?1?, I?B??, NF??B and COX?2 in a dose?dependent manner. In conclusion, our data suggest that emodin attenuates LPS- and HR?induced intestinal epithelial barrier dysfunction by inhibiting the HIF?1? and NF??B signaling pathways and preventing the damage caused to the TJ barrier (shown by the decrease in the expression of ZO?1). PMID:25318952

Lei, Qi; Qiang, Fu; Chao, Du; Di, Wu; Guoqian, Zhang; Bo, Yuan; Lina, Yan

2014-12-01

165

MR imaging and targeting of a specific alveolar macrophage subpopulation in LPS-induced COPD animal model using antibody-conjugated magnetic nanoparticles  

PubMed Central

Purpose Targeting and noninvasive imaging of a specific alveolar macrophage subpopulation in the lung has revealed the importance for early and better diagnosis and therapy of chronic obstructive pulmonary disease (COPD). In this study, the in vivo effect of pulmonary administration of iron oxide nanoparticles on the polarization profile of macrophages was assessed, and a noninvasive free-breathing magnetic resonance imaging (MRI) protocol coupled with the use of biocompatible antibody-conjugated superparamagnetic iron oxide (SPIO) nanoparticles was developed to enable specific targeting and imaging of a particular macrophage subpopulation in lipopolysaccharide-induced COPD mice model. Materials and methods Enzyme-linked immunosorbent assay, Real-time polymerase chain reaction, and flow cytometry analysis were performed to assess the biocompatibility of PEGylated dextran-coated SPIO nanoparticles. Specific biomarkers for M1 and M2 macrophages subsets were selected for conjugation with magnetic nanoparticles. MRI protocol using ultra-short echo time sequence was optimized to enable simultaneous detection of inflammation progress in the lung and detection of macrophages subsets. Flow cytometry and immunohistochemistry analysis were finally performed to confirm MRI readouts and to characterize the polarization profile of targeted macrophages. Results The tested SPIO nanoparticles, under the current experimental conditions, were found to be biocompatible for lung administration in preclinical settings. Cluster of differentiation (CD)86- and CD206-conjugated magnetic nanoparticles enabled successful noninvasive detection of M1 and M2 macrophage subpopulations, respectively, and were found to co-localize with inflammatory regions induced by lipopolysaccharide challenge. No variation in the polarization profile of targeted macrophages was observed, even though a continuum switch in their polarization might occur. However, further confirmatory studies are required to conclusively establish this observation. Conclusion Coupling of magnetic iron oxide nanoparticles with a specific antibody targeted to a particular macrophage subpopulation could offer a promising strategy for an early and better diagnosis of pulmonary inflammatory diseases using noninvasive MRI. PMID:24711699

Al Faraj, Achraf; Shaik, Asma Sultana; Afzal, Sibtain; Al Sayed, Baraa; Halwani, Rabih

2014-01-01

166

Inhibitory mechanism of 10-hydroxy-trans-2-decenoic acid (royal jelly acid) against lipopolysaccharide- and interferon-?-induced nitric oxide production.  

PubMed

Royal jelly acid, 10-hydroxy-trans-2-decenoic acid (10H2DA), is a major lipid component of royal jelly, which is the exclusive diet of queen honeybees. Previously, we showed partial inhibition of lipopolysaccharide (LPS)-induced NF-?B activation by 10H2DA. In this study, the ability of 10H2DA to inhibit LPS-induced nitric oxide (NO) production was investigated. LPS-induced NO production and inducible NO synthase (iNOS) gene transcription were inhibited by 10H2DA. LPS-stimulated interferon (IFN)-? production, IFN regulatory factor-1 induction and IFN-stimulated response element activation, which are required for iNOS induction, were unaffected by 10H2DA. IFN-?-induced NO production, however, was significantly inhibited by 10H2DA. Furthermore, IFN-?-induced nuclear factor (NF)-?B activation and tumour necrosis factor (TNF)-? production were significantly inhibited by 10H2DA, and TNF-?-induced NF-?B activation was also inhibited by 10H2DA. These results and our previous study suggest that 10H2DA inhibits LPS- and IFN-?-induced NO production via inhibition of NF-?B activation induced by LPS or IFN-?. PMID:23079939

Sugiyama, Tsuyoshi; Takahashi, Keita; Kuzumaki, Akihiro; Tokoro, Shunji; Neri, Paola; Mori, Hiroshi

2013-04-01

167

Fluoxetine up-regulates expression of cellular FLICE-inhibitory protein and inhibits LPS-induced apoptosis in hippocampus-derived neural stem cell  

SciTech Connect

Fluoxetine is a widely used antidepressant compound which inhibits the reuptake of serotonin in the central nervous system. Recent studies have shown that fluoxetine can promote neurogenesis and improve the survival rate of neurons. However, whether fluoxetine modulates the proliferation or neuroprotection effects of neural stem cells (NSCs) needs to be elucidated. In this study, we demonstrated that 20 {mu}M fluoxetine can increase the cell proliferation of NSCs derived from the hippocampus of adult rats by MTT test. The up-regulated expression of Bcl-2, Bcl-xL and the cellular FLICE-inhibitory protein (c-FLIP) in fluoxetine-treated NSCs was detected by real-time RT-PCR. Our results further showed that fluoxetine protects the lipopolysaccharide-induced apoptosis in NSCs, in part, by activating the expression of c-FLIP. Moreover, c-FLIP induction by fluoxetine requires the activation of the c-FLIP promoter region spanning nucleotides -414 to -133, including CREB and SP1 sites. This effect appeared to involve the phosphatidylinositol-3-kinase-dependent pathway. Furthermore, fluoxetine treatment significantly inhibited the induction of proinflammatory factor IL-1{beta}, IL-6, and TNF-{alpha} in the culture medium of LPS-treated NSCs (p < 0.01). The results of high performance liquid chromatography coupled to electrochemical detection further confirmed that fluoxentine increased the functional production of serotonin in NSCs. Together, these data demonstrate the specific activation of c-FLIP by fluoxetine and indicate the novel role of fluoxetine for neuroprotection in the treatment of depression.

Chiou, S.-H. [Department of Medical Research and Education, Taipei Veterans General Hospital and National Yang-Ming University, Taipei, Taiwan (China) and Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan (China)]. E-mail: shchiou@vghtpe.gov.tw; Chen, S.-J. [Department of Ophthalmology, Taipei Veterans General Hospital and National Yang-Ming University, Taipei, Taiwan (China)]. E-mail: sjchen@vghtpe.gov.tw; Peng, C-H. [Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan (China); Department of Ophthalmology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China); Chang, Y.-L. [Department of Pharmacy, Taipei Veterans General Hospital and National Yang-Ming University, Taipei, Taiwan (China); Ku, H.-H. [Institute of Anatomy and Cell Biology, National Yang-Ming University, Taipei, Taiwan (China); Hsu, W.-M. [Department of Ophthalmology, Taipei Veterans General Hospital and National Yang-Ming University, Taipei, Taiwan (China); Ho, Larry L.-T. [Department of Medical Research and Education, Taipei Veterans General Hospital and National Yang-Ming University, Taipei, Taiwan (China); Lee, C.-H. [Department of Medical Research and Education, Taipei Veterans General Hospital and National Yang-Ming University, Taipei, Taiwan (China)

2006-05-05

168

Effects of phenylethanoid glycosides from Digitalis purpurea L. on the expression of inducible nitric oxide synthase.  

PubMed

We have isolated four different phenylethanoid glycosides (purpureaside A, desrhamnosyl acteoside, calceolarioside B and plantainoside D) from the leaves of Digitalis purpurea (foxglove). The effects of these glycosides on activator protein-1 (AP-1)-mediated inducible nitric oxide synthase (iNOS) gene expression in the Raw264.7 macrophage cell line have been studied. Of these four glycosides, purpureaside A potently inhibited iNOS induction by lipopolysaccharide (LPS). Increase in iNOS mRNA by LPS was completely suppressed by purpureaside A. Purpureaside A did not significantly affect LPS-inducible nuclear factor-kappaB (NF-kappaB) activation or the nuclear translocation of p65. Moreover, a reporter gene assay using AP-1 specific luciferase reporter revealed that the enhanced activity of AP-1 by LPS was completely abolished in cells treated with purpureaside A. These results demonstrated that purpureaside A inhibited LPS-inducible iNOS expression in macrophages through the suppression of AP-1, but not of NF-kappaB. PMID:15969951

Oh, Jae Wook; Lee, Jeong Yong; Han, Song Hee; Moon, Young Hee; Kim, Yoon Gyoon; Woo, Eun-Rhan; Kang, Keon Wook

2005-07-01

169

Microarray and Pathway Analysis Reveal Distinct Mechanisms Underlying Cannabinoid-Mediated Modulation of LPS-Induced Activation of BV-2 Microglial Cells  

PubMed Central

Cannabinoids are known to exert immunosuppressive activities. However, the mechanisms which contribute to these effects are unknown. Using lipopolysaccharide (LPS) to activate BV-2 microglial cells, we examined how ?9-tetrahydrocannabinol (THC), the major psychoactive component of marijuana, and cannabidiol (CBD) the non-psychoactive component, modulate the inflammatory response. Microarray analysis of genome-wide mRNA levels was performed using Illumina platform and the resulting expression patterns analyzed using the Ingenuity Pathway Analysis to identify functional subsets of genes, and the Ingenuity System Database to denote the gene networks regulated by CBD and THC. From the 5338 transcripts that were differentially expressed across treatments, 400 transcripts were found to be upregulated by LPS, 502 by CBD+LPS and 424 by THC+LPS, while 145 were downregulated by LPS, 297 by CBD+LPS and 149 by THC+LPS, by 2-fold or more (p?0.005). Results clearly link the effects of CBD and THC to inflammatory signaling pathways and identify new cannabinoid targets in the MAPK pathway (Dusp1, Dusp8, Dusp2), cell cycle related (Cdkn2b, Gadd45a) as well as JAK/STAT regulatory molecules (Socs3, Cish, Stat1). The impact of CBD on LPS-stimulated gene expression was greater than that of THC. We attribute this difference to the fact that CBD highly upregulated several genes encoding negative regulators of both NF?B and AP-1 transcriptional activities, such as Trib3 and Dusp1 known to be modulated through Nrf2 activation. The CBD-specific expression profile reflected changes associated with oxidative stress and glutathione depletion via Trib3 and expression of ATF4 target genes. Furthermore, the CBD affected genes were shown to be controlled by nuclear factors usually involved in regulation of stress response and inflammation, mainly via Nrf2/Hmox1 axis and the Nrf2/ATF4-Trib3 pathway. These observations indicate that CBD, and less so THC, induce a cellular stress response and that this response underlies their high immunosuppressant activities. PMID:23637839

Juknat, Ana; Kozela, Ewa; Rimmerman, Neta; Levy, Rivka; Gao, Fuying; Coppola, Giovanni; Geschwind, Daniel; Vogel, Zvi

2013-01-01

170

San-Huang-Xie-Xin-Tang reduces lipopolysaccharides-induced hypotension and inflammatory mediators  

Microsoft Academic Search

San-Huang-Xie-Xin-Tang (SHXT) is a traditional Chinese medicinal formula containing Coptidis rhizoma, Scutellariae radix and Rhei rhizoma. The present study aimed to determine the preventive effects of standardized SHXT on lipopolysaccharides (LPS)-induced arterial hypotension, protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), cytokines formation and prostaglandin E2 (PGE2) production. LPS-induced activation of iNOS has been recognized to increase

Yi-Ching Lo; Pei-Ling Tsai; Yaw-Bin Huang; Kuo-Pyng Shen; Yi-Hung Tsai; Yang-Chang Wu; Yung-Hsiung Lai; Ing-Jun Chen

2005-01-01

171

LPS-induced inflammation in the chicken is associated with CCAAT/enhancer binding protein beta-mediated fat mass and obesity associated gene down-regulation in the liver but not hypothalamus  

PubMed Central

Background The fat mass and obesity associated gene (FTO) is widely investigated in humans regarding its important roles in obesity and type 2 diabetes. Studies in mammals demonstrate that FTO is also associated with inflammation markers. However, the association of FTO with inflammation in chickens remains unclear. In this study, male chickens on day 28 posthatching were injected intraperitoneally with lipopolysaccharide (LPS) or saline to investigate whether the FTO gene is involved in LPS-induced inflammation. Results We detected significant down-regulation of FTO mRNA in the liver (P?

2013-01-01

172

Immunologic properties of bacterial lipopolysaccharide (LPS). II. The unresponsiveness of C3H/HeJ Mouse spleen cells to LPS-induced mitogenesis is dependent on the method used to extract LPS  

PubMed Central

The C3H/HeJ mouse strain, previously shown to be a nonresponder to bacterial lipopolysaccharide (LPS)-induced mitogenesis in vitro, was demonstrated by the present studies to be competent to respond mitogenically to LPS, but only to LPS preparations obtained by selected extraction methods. These preparations appear to be confined to LPS isolated by mild extraction techniques, such as TCA or butanol. In contrast, those obtained by techniques utilizing phenol were only weakly stimulatory or completely nonstimulatory for spleen cells from the C3H/HeJ. All LPS preparations tested, on the other hand, were highly stimulatory for cells from another mouse strain, namely the C3H/St. The critical importance of the method of extraction of LPS on its mitogenic activity for C3H/HeJ cells was stressed by experiments in which LPS was prepared from Escherichia coli K235 using either of two procedures. In these experiments, phenol-extracted LPS, although mitogenic in the C3H/St, was completely nonstimulatory in the C3H/HeJ; whereas, butanol-extracted LPS was highly stimulatory in both strains of mice. This striking difference was attributed to a destructive effect of phenol on LPS, as demonstrated by the fact that treatment of butanol LPS with phenol resulted in a total loss of its mitogenic activity in the C3H/HeJ, but in only a partial loss in the C3H/St. In general, the mitogenic response observed with selected LPS preparations in the C3H/HeJ was quantitatively lower and more transient than that seen with the C3H/St, although qualitatively these responses appeared to be similar. This was evidenced by the observation that in both mouse strains LPS was a specific mitogen for B cells, a property which was also attributed in both strains to the same distinct structural region of the LPS molecule, that is lipid A. A preparation of LPS that failed to stimulate B cells from the C3H/HeJ nonetheless had the capacity to block activation of these B cells by a stimulatory preparation of LPS. These results strongly suggest that mitogenic stimulation of B cells by LPS is a function of the structural integrity of both the LPS molecule and putative B-cell receptors for LPS. PMID:1104747

1975-01-01

173

Alachlor and carbaryl suppress lipopolysaccharide-induced iNOS expression by differentially inhibiting NF-{kappa}B activation  

SciTech Connect

Nitric oxide (NO) produced by macrophages plays an important role in host defense and inflammation. We found that two agrochemicals, alachlor and carbaryl, inhibit lipopolysaccharide (LPS)-induced NO production by macrophages. In the present study, we investigated this inhibitory mechanism in RAW 264 cells. Both chemicals inhibited LPS-induced iNOS protein and mRNA expression as well as murine iNOS promoter activity. When treating these chemicals with reducing agents, the inhibition by carbaryl was reversed, but not the inhibition by alachlor. These chemicals also inhibited LPS-induced interferon-{beta} (IFN-{beta}) expression, an indispensable factor for LPS-induced iNOS expression. The inhibited iNOS expression, however, was not restored by exogenous IFN-{beta} supplementation. LPS-induced nuclear translocation of NF-{kappa}B, which is necessary for the expression of IFN-{beta} and iNOS, was inhibited by these chemicals: however, the LPS-induced degradation of I{kappa}B-{alpha} and I{kappa}B-{beta} was inhibited only by alachlor. These results indicate that alachlor and carbaryl differentially impair the LPS-induced NF-{kappa}B activation, leading to the inhibition of NO production.

Shimomura-Shimizu, Mifumi [Division of Microbiology, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501 (Japan); Sugiyama, Kei-ichi [Division of Microbiology, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501 (Japan); Muroi, Masashi [Division of Microbiology, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501 (Japan); Tanamoto, Ken-ichi [Division of Microbiology, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501 (Japan)]. E-mail: tanamoto@nihs.go.jp

2005-07-08

174

Cryptomeria japonica Essential Oil Inhibits the Growth of Drug-Resistant Skin Pathogens and LPS-Induced Nitric Oxide and Pro-Inflammatory Cytokine Production  

Microsoft Academic Search

In this study, the chemical composition of Cryptomeria japonica essential oil (CJE) was analyzed and its biological activities were tested. CJE was obtained by steam distillation from leaves collected from Jeju Island and analyzed by gas chromatography (GC)-flame ionization detection (FID) and GC-MS. Kaurene (17.20 %), elemol (10.88 %), (-eudesmol (9.41 %), and sabinene (8.86 %) were the major compo-

WEON-JONG YOON; SANG-SUK KIM; TAE-HEON OH; NAM HO LEE; CHANG-GU HYUN

175

Fimasartan, anti-hypertension drug, suppressed inducible nitric oxide synthase expressions via nuclear factor-kappa B and activator protein-1 inactivation.  

PubMed

Since inhibition of angiotensin II type 1 (AT1) receptor reduces chronic inflammation associated with hypertension, we evaluated the anti-inflammatory potential and the underlying mechanism of fimasartan, a Korean Food and Drug Administration approved anti-hypertension drug, in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Fimasartan suppressed the expressions of inducible nitric oxide synthase (iNOS) by down-regulating its transcription, and subsequently inhibited the productions of nitric oxide (NO). In addition, fimasartan attenuated LPS-induced transcriptional and DNA-binding activities of nuclear factor-kappa B (NF-?B) and activator protein-1 (AP-1). These reductions were accompanied by parallel reductions in the nuclear translocation of NF-?B and AP-1. Taken together, our data suggest that fimasartan down-regulates the expression of the iNOS in macrophages via NF-?B and AP-1 inactivation. PMID:23449332

Ryu, Suran; Shin, Ji-Sun; Cho, Young-Wuk; Kim, Hyoung Kook; Paik, Soo Heui; Lee, Joo Han; Chi, Yong Ha; Kim, Ji Han; Kim, Je Hak; Lee, Kyung-Tae

2013-01-01

176

Inducible Nitric Oxide Synthase - Time for Reappraisal  

Microsoft Academic Search

Inducible nitric oxide synthase (iNOS) is one of three key enzymes generating nitric oxide (NO) from the amino acid L-arginine. iNOS-derived NO plays an important role in numerous physiological and pathophysiological conditions, e.g. blood pressure regulation, inflammation, infection, and the onset and progression of malignant diseases. iNOS has been conjectured both as a marker and a therapeutic target in these

Philipp Lirk; Georg Hoffmann; Josef Rieder

2002-01-01

177

The NADPH oxidase inhibitor apocynin induces nitric oxide synthesis via oxidative stress  

SciTech Connect

We have recently shown that apocynin elicits an oxidative stress in N11 mouse glial cells and other cell types. Here we report that apocynin increased the accumulation of nitrite, the stable derivative of nitric oxide (NO), in the extracellular medium of N11 cell cultures, and the NO synthase (NOS) activity in cell lysates. The increased synthesis of NO was associated with increased expression of inducible NOS (iNOS) mRNA, increased nuclear translocation of the redox-sensitive transcription factor NF-{kappa}B and decreased intracellular level of its inhibitor IkB{alpha}. These effects, accompanied by increased production of H{sub 2}O{sub 2}, were very similar to those observed after incubation with bacterial lipopolysaccharide (LPS) and were inhibited by catalase. These results suggest that apocynin, similarly to LPS, induces increased NO synthesis by eliciting a generation of reactive oxygen species (ROS), which in turn causes NF-{kappa}B activation and increased expression of iNOS. Therefore, the increased bioavailability of NO reported in the literature after in vivo or in vitro treatments with apocynin might depend, at least partly, on the drug-elicited induction of iNOS, and not only on the inhibition of NADPH oxidase and the subsequent decreased scavenging of NO by oxidase-derived ROS, as it is often supposed.

Riganti, Chiara [Dipartimento di Genetica, Biologia e Biochimica, Universita di Torino, Via Santena 5/bis, 10126 Torino (Italy)], E-mail: chiara.riganti@unito.it; Costamagna, Costanzo; Doublier, Sophie; Miraglia, Erica; Polimeni, Manuela; Bosia, Amalia; Ghigo, Dario [Dipartimento di Genetica, Biologia e Biochimica, Universita di Torino, Via Santena 5/bis, 10126 Torino (Italy)

2008-05-01

178

A molecular pharmacology study into the anti-inflammatory actions of Euphorbia hirta L. on the LPS-induced RAW 264.7 cells through selective iNOS protein inhibition  

Microsoft Academic Search

Euphorbia hirta L. has been widely used in India and Chinese society. The molecular pharmacology basis of its anti-inflammatory effect is\\u000a revealed in this work. The ethanol extract of Euphorbia hirta L. (Eh) and its active component were studied in lipopolysaccharide (LPS)-activated macrophage cells (RAW 264.7) as an established\\u000a inflammation model. After activation, nitric oxide (NO) production and expression of

Mei-Fen Shih; Yih-Dih Cheng; Chia-Rui Shen; Jong-Yuh Cherng

2010-01-01

179

Anti-angiogenic and inhibitory activity on inducible nitric oxide production of the mushroom Ganoderma lucidum  

Microsoft Academic Search

Fresh fruit bodies of Ganoderma lucidum were extracted with 70% ethanol at room temperature. The extract (GL) showed significant anti-angiogenic activity, which was detected using a chick embryo chorioallantoic membrane assay. GL significantly inhibited LPS-induced NO production in RAW 264.7 macrophages. These results support the anti-tumor effect of Ganoderma lucidum.

Yun Seon Song; Sun-Hyoung Kim; Jae-Hoon Sa; Changbae Jin; Chang-Jin Lim; Eun-Hee Park

2004-01-01

180

cis-Ampelopsin E, a stilbene isolated from the seeds of Paeonia suffruticosa, inhibits lipopolysaccharide-stimulated nitric oxide production in RAW 264.7 macrophages via blockade of nuclear factor-kappa B signaling pathway.  

PubMed

Stilbenes are a class of compounds that has been reported to inhibit a variety of pathological processes during inflammatory reactions. In this study, cis-ampelopsin E, a stilbene isolated from the seeds of Paeonia suffruticosa, was shown to dose-dependently reduce the nitric oxide (NO) production from lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. The reduction in the nitric oxide release occurred in parallel with the comparable inhibition of inducible nitric oxide synthase (iNOS) enzyme expression, which was achieved by cis-ampelopsin E's suppressive effect on nuclear factor-kappa B (NF-?B) signaling activation. By inhibiting LPS-induced inhibitor kinase (IKK?/?) phosphorylation, cis-ampelopsin E significantly decreased LPS-induced I?B? phosphorylation, prevented I?B? degradation, and subsequently reduced the translocating of transcription factor p65 into the nucleus. As a result, the LPS-induced upregulation of NF-?B transcriptional activity was efficiently inhibited. Moreover, it is revealed that cis-ampelopsin E inhibited LPS-induced cyclooxygenase-2 (Cox-2) expression, cPLA2 activation and prostaglandin E2 (PGE2) production. These results, taken together, suggested that cis-ampelopsin E might exert potential anti-inflammatory effects via blockage of the NF-?B signaling pathway. PMID:21881241

Cai, Tiange; Cai, Yu

2011-01-01

181

Polyphenolics from ac?ai? ( Euterpe oleracea Mart.) and red muscadine grape (Vitis rotundifolia ) protect human umbilical vascular Endothelial cells (HUVEC) from glucose- and lipopolysaccharide (LPS)-induced inflammation and target microRNA-126.  

PubMed

Endothelial anti-inflammatory effects of ac?ai? (Ac) and red muscadine grape (Gp) polyphenolics have not been extensively investigated. It was hypothesized that polyphenolics from Ac and Gp exert comparable protective effects in human vascular endothelial cells (HUVEC) upon inflammatory stress. Furthermore, this study investigated whether microRNAs relevant to endothelial function might be regulated by Ac and Gp. Results showed that Ac and Gp (5-20 mg gallic acid equivalent/L) protected HUVEC against glucose-induced oxidative stress and inflammation. Glucose-induced expression of interleukin-6 and -8 was down-regulated by Ac and Gp at mRNA and protein levels. Upon lipopolysaccharide (LPS; 1 ?g/L)-induced inflammation, Ac and Gp inhibited gene expression of adhesion molecules and NF-?B activation to similar extents, although Gp was more effective in decreasing PECAM-1 and ICAM-1 protein. Of the screened microRNAs, only microRNA-126 expression was found to be modulated by Ac and Gp as the underlying mechanism to inhibit gene and protein expression of VCAM-1. PMID:21682256

Noratto, Giuliana D; Angel-Morales, Gabriela; Talcott, Stephen T; Mertens-Talcott, Susanne U

2011-07-27

182

Atypical “seizure-like” activity in cortical reverberating networks in vitro can be caused by LPS-induced inflammation: a multi-electrode array study from a hundred neurons  

PubMed Central

We show here that a mild sterile inflammation induced by the endotoxin lipopolysaccharide (LPS), in a neuron/astrocyte/microglial cortical network, modulates neuronal excitability and can initiate long-duration burst events resembling epileptiform seizures, a recognized feature of various central nervous neurodegenerative, neurological and acute systemic diseases associated with neuroinflammation. To study this action, we simultaneously analyzed the reverberating bursting activity of a hundred neurons by using in vitro multi-electrode array methods. ?5 h after LPS application, we observed a net increase in the average number of spikes elicited in engaged cells and within each burst, but no changes neither in spike waveforms nor in burst rate. This effect was characterized by a slow, twofold exponential increase of the burst duration and the appearance of rarely occurring long burst events that were never seen during control recordings. These changes and the time-course of microglia-released proinflammatory cytokine, tumor necrosis factor-alpha (TNF-?), were blocked by pre-treatment with 50 nM minocycline, an established anti-inflammatory agent which was inactive when applied alone. Assay experiments also revealed that application of 60 pM exogenous TNF-? after 12–15 h, produced non-washable changes of neuronal excitability, completely different from those induced by LPS, suggesting that TNF-? release alone was not responsible for our observed findings. Our results indicate that the link between neuroinflammation and hyperexcitability can be unveiled by studying the long-term activity of in vitro neuronal/astrocyte/microglial networks. PMID:25404893

Gullo, Francesca; Amadeo, Alida; Donvito, Giulia; Lecchi, Marzia; Costa, Barbara; Constanti, Andrew; Wanke, Enzo

2014-01-01

183

Endotoxin-induced nitric oxide production rescues airway growth and maturation in atrophic fetal rat lung explants  

SciTech Connect

Inflammation induces premature maturation of the fetal lung but the signals causing this effect remain unclear. We determined if nitric oxide (NO) synthesis, evoked by Escherichia coli lipopolysaccharide (LPS, 2 {mu}g ml{sup -1}), participated in this process. Fetal rat lung airway surface complexity rose 2.5-fold over 96 h in response to LPS and was associated with increased iNOS protein expression and activity. iNOS inhibition by N6-(1-iminoethyl)-L-lysine-2HCl (L-NIL) abolished this and induced airway atrophy similar to untreated explants. Surfactant protein-C (SP-C) expression was also induced by LPS and abolished by L-NIL. As TGF{beta} suppresses iNOS activity, we determined if feedback regulation modulated NO-dependent maturation. LPS induced TGF{beta}1 release and SMAD4 nuclear translocation 96 h after treatment. Treatment of explants with a blocking antibody against TGF{beta}1 sustained NO production and airway morphogenesis whereas recombinant TGF{beta}1 antagonized these effects. Feedback regulation of NO synthesis by TGF{beta} may, thus, modulate airway branching and maturation of the fetal lung.

Rae, C. [Division of Maternal and Child Health Sciences, Ninewells Hospital and Medical School, University of Dundee, Dundee, DD1 9SY Scotland (United Kingdom); Cherry, J.I. [Division of Maternal and Child Health Sciences, Ninewells Hospital and Medical School, University of Dundee, Dundee, DD1 9SY Scotland (United Kingdom); Land, F.M. [Division of Maternal and Child Health Sciences, Ninewells Hospital and Medical School, University of Dundee, Dundee, DD1 9SY Scotland (United Kingdom); Land, S.C. [Division of Maternal and Child Health Sciences, Ninewells Hospital and Medical School, University of Dundee, Dundee, DD1 9SY Scotland (United Kingdom)]. E-mail: s.c.land@dundee.ac.uk

2006-10-13

184

Mycophenolic acid inhibits activation of inducible nitric oxide synthase in rodent fibroblasts  

PubMed Central

Mycophenolate mofetil (MMF) is an immunosuppressive drug that acts as a selective inhibitor of inosine monophosphate dehydrogenase (IMPDH). MMF has recently been shown to inhibit the enzymatic activity of inducible NO synthase (iNOS) and subsequent production of the cytotoxic free radical nitric oxide (NO) in endothelial cells. We here investigated the effect of bioactive MMF compound mycophenolic acid (MPA) on iNOS-mediated NO synthesis in fibroblasts, which are important source of NO in rheumatoid arthritis and during rejection of solid organ transplants. MPA exerted dose-dependent inhibition of NO synthesis, measured as nitrite accumulation, in IFN-? + LPS-stimulated L929 mouse fibroblast cell line and rat primary fibroblasts. The effect of MPA was not mediated through interference with IMPDH-dependent synthesis of iNOS co-factor BH4 and subsequent suppression of iNOS enzymatic activity, as direct BH4 precursor sepiapterin failed to block the action of the drug. MPA suppressed the IFN-? + LPS-induced expression of fibroblast iNOS protein, as well as mRNA for iNOS and its transcription factor IRF-1, as assessed by cell-based ELISA and semiquantitative RT-PCR, respectively. MPA suppression of fibroblast NO release, iNOS, and IRF-1 activation, was efficiently prevented by exogenous guanosine, indicating that the drug acted through reduction of IMPDH-dependent synthesis of guanosine nucleotides. These results suggest that MPA inhibits NO production in fibroblasts by blocking guanosine nucleotide-dependent expression of iNOS gene, through mechanisms that might involve the interference with the induction of iNOS transcription factor IRF-1. PMID:12699411

MILJKOVIC, Dj; CVETKOVIC, I; STOSIC-GRUJICIC, S; TRAJKOVIC, V

2003-01-01

185

San-Huang-Xie-Xin-Tang reduces lipopolysaccharides-induced hypotension and inflammatory mediators.  

PubMed

San-Huang-Xie-Xin-Tang (SHXT) is a traditional Chinese medicinal formula containing Coptidis rhizoma, Scutellariae radix and Rhei rhizoma. The present study aimed to determine the preventive effects of standardized SHXT on lipopolysaccharides (LPS)-induced arterial hypotension, protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), cytokines formation and prostaglandin E2 (PGE2) production. LPS-induced activation of iNOS has been recognized to increase cytokines and nitric oxide, some of them play predominant roles in sepsis. Intravenous injection of LPS (10 mg/kg) caused a marked decrease of the mean arterial pressure in normotensive rats. However, the LPS-induced arterial hypotension was inhibited by SHXT (0.01 and 0.03 g/kg), when it was given 30 min before LPS. Moreover, plasma level of cytokines and PGE2 were lowered by SHXT. In RAW 264.7 cells, SHXT (20-200 microg/ml) dose-dependently inhibited LPS (1 microg/ml)-induced iNOS and COX-2 expression, and it also significantly decreased LPS-induced cytokines in a dose-dependent manner. In conclusion, our data suggest that SHXT prevented LPS-induced arterial hypotension, which might be mediated through its inhibition activities on the expression of iNOS and COX-2, cytokines formation and PGE2 production. Therefore, its protection activity against LPS-induced arterial hypotension and inflammatory mediators release might be beneficial in the treatment of endotoxin shock and/or associated inflammation. PMID:15588656

Lo, Yi-Ching; Tsai, Pei-Ling; Huang, Yaw-Bin; Shen, Kuo-Pyng; Tsai, Yi-Hung; Wu, Yang-Chang; Lai, Yung-Hsiung; Chen, Ing-Jun

2005-01-01

186

Nitric Oxide-Mediated Maintenance of Redox Homeostasis Contributes to NPR1-Dependent Plant Innate Immunity Triggered by Lipopolysaccharides1[C][W  

PubMed Central

The perception of lipopolysaccharides (LPS) by plant cells can lead to nitric oxide (NO) production and defense gene induction. However, the signaling cascades underlying these cellular responses have not yet been resolved. This work investigated the biosynthetic origin of NO and the role of NONEXPRESSOR OF PATHOGENESIS-RELATED GENES1 (NPR1) to gain insight into the mechanism involved in LPS-induced resistance of Arabidopsis (Arabidopsis thaliana). Analysis of inhibitors and mutants showed that LPS-induced NO synthesis was mainly mediated by an arginine-utilizing source of NO generation. Furthermore, LPS-induced NO caused transcript accumulation of alternative oxidase genes and increased antioxidant enzyme activity, which enhanced antioxidant capacity and modulated redox state. We also analyzed the subcellular localization of NPR1 to identify the mechanism for protein-modulated plant innate immunity triggered by LPS. LPS-activated defense responses, including callose deposition and defense-related gene expression, were found to be regulated through an NPR1-dependent pathway. In summary, a significant NO synthesis induced by LPS contributes to the LPS-induced defense responses by up-regulation of defense genes and modulation of cellular redox state. Moreover, NPR1 plays an important role in LPS-triggered plant innate immunity. PMID:22926319

Sun, Aizhen; Nie, Shengjun; Xing, Da

2012-01-01

187

Nitric oxide mediates renal vasodilation during erythropoietin-induced polycythemia  

Microsoft Academic Search

Nitric oxide mediates renal vasodilation during erythropoietin-induced polycythemia. The renal blood flow (RBF) of patients with polycythemia rubra vera is increased despite the high hematocrit (Hct) which elevates the whole blood viscosity. Since blood viscosity determines the shear force on the endothelium which is a major stimulus to nitric oxide (NO) release, we investigated the hypothesis that renal vasodilation during

Christopher S Wilcox; Xiaolin Deng; Avon H Doll; Harold Snellen; William J Welch

1993-01-01

188

Structural significance of the acyl group at the C-10 position and the A ring of the taxane core of paclitaxel for inducing nitric oxide and tumor necrosis factor production by murine macrophages.  

PubMed

The antitumor agent, paclitaxel (Taxol), mimics the actions of lipopolysaccharide (LPS) on murine macrophages (Mphi). Various synthetic analogs of paclitaxel were examined for their potencies to induce nitric oxide (NO) and tumor necrosis factor (TNF) production by murine peritoneal Mphi, and by human peripheral blood cells. The benzoyl group at C-2, the hydroxy group at C-7 and the acetyl group at C-10 were found to be critically important sites to activate murine Mphi. Nor-seco-taxoid analogs lacking the A ring of the taxane core of paclitaxel were inactive, but inhibit paclitaxel- or LPS-induced NO production. All the compounds tested did not induce TNF production by human blood cells. PMID:10930572

Kirikae, T; Ojima, I; Fuero-Oderda, C; Lin, S; Kirikae, F; Hashimoto, M; Nakanoc, M

2000-08-01

189

Cytotoxicity and inhibition of nitric oxide in lipopolysaccharide induced mammalian cell lines by aqueous extracts of brown seaweed.  

PubMed

Aqueous extracts obtained from five Malaysian brown seaweeds, Sargassum duplicatum, Sargassum binderi, Sargassum fulvellum, Padina australis, and Turbinaria turbinata, were investigated for their abilities to inhibit nitric oxide (NO) production in lipopolysaccharide (LPS)-induced macrophage RAW 264.7 cell lines as well as to determine their chemical composition. The percentage yield of extracts varied among species, with P. australis having the lowest yield and T. turbinata having the highest yield. The chemical compositions of the extracts showed that the percentage of sulfate ions as well as uronic acid and total sugar content varied significantly. All extracts contained high fucose and inhibited NO secretion in a dose-dependent manner. Extracts of P. australis and T. turbinata dosed at 200 ?g/mL were able to inhibit NO secretion by > 75%. Furthermore, cytotoxicity assays revealed that some extracts were moderately toxic, while others were not. Based on these results, brown seaweed of Malaysian origin should be investigated for the production of additional anti-inflammatory compounds. PMID:25007746

Jaswir, Irwandi; Monsur, Hammed Ademola; Simsek, Senay; Amid, Azura; Alam, Zahangir; bin Salleh, Mohammad Noor; Tawakalit, Asiyanbi-Hammed; Octavianti, Fitri

2014-01-01

190

Polar lipids from the marine macroalga Palmaria palmata inhibit lipopolysaccharide-induced nitric oxide production in RAW264.7 macrophage cells.  

PubMed

The EtOAc soluble fraction of a MeOH/CHCl3 extract of Palmaria palmata showed strong nitric oxide (NO) inhibitory activity against lipopolysaccharide (LPS)-induced NO production in murine RAW264.7 cells. NO inhibition-guided isolation led to identification of three new polar lipids including a sulfoquinovosyl diacylglycerol (SQDG) (2S)-1-O-eicosapentaenoyl-2-O-myristoyl-3-O-(6-sulfo-?-D-quinovopyranosyl)-glycerol (1) and two phosphatidylglycerols, 1-O-eicosapentaenoyl-2-O-trans-3-hexadecenoyl-3-phospho-(1'-glycerol)-glycerol (3) and 1-O-eicosapentaenoyl-2-O-palmitoyl-3-phospho-(1'-glycerol)-glycerol (4) from the EtOAc fraction. Seven known lipids were also isolated including a SQDG (2), a phospholipid (5) and five galactolipids (6-10). Structures of the isolated lipids were elucidated by spectral analyses. The isolated SQDGs, phosphatidylglycerols and phospholipid possessed strong and dose-dependent NO inhibitory activity compared to N(G)-methyl-L-arginine acetate salt (L-NMMA), a well-known NO inhibitor used as a positive control. Further study suggested that these polar lipids suppressed NO production through down-regulation of inducible nitric oxide synthase (iNOS). PMID:24569177

Banskota, Arjun H; Stefanova, Roumiana; Sperker, Sandra; Lall, Santosh P; Craigie, James S; Hafting, Jeff T; Critchley, Alan T

2014-05-01

191

Zinc protoporphyrin inhibition of lipopolysaccharide-, lipoteichoic acid-, and peptidoglycan-induced nitric oxide production through stimulating iNOS protein ubiquitination  

SciTech Connect

In the present study, zinc protoporphyrin (ZnPP), but not ferric protoporphyrin (FePP), tin protoporphyrin (SnPP), or zinc chloride (ZnCl{sub 2}), at the doses of 0.5, 1, and 2 {mu}M, dose-dependently inhibited lipopolysaccharide- (LPS), lipoteichoic acid (LTA), and peptidoglycan (PGN)-induced inducible nitric oxide (iNOS) and nitric oxide (NO) production with an increase in heme oxygenase 1 (HO-1) protein in RAW264.7 macrophages in a serum-free condition. NO inhibition and HO-1 induction by ZnPP were blocked by the separate addition of fetal bovine serum (FBS) and bovine serum albumin (BSA). A decrease in the iNOS/NO ratio and an increase in HO-1 protein by ZnPP were identified in three different conditions including ZnPP pretreatment, ZnPP co-treatment, and ZnPP post-treatment with LPS and LTA. Activation of c-Jun N-terminal kinases (JNKs) and extracellular regulated kinases (ERKs) were detected in LPS-, LTA-, and PGN-treated RAW264.7 cells, and iNOS/NO production was blocked by adding the JNK inhibitor, SP600125, but not the ERK inhibitor, PD98059. However, ZnPP addition potentiated ERK and JNK protein phosphorylation stimulated by LPS, LTA, and PGN. Increases in total protein ubiquitination and ubiquitinated iNOS proteins were detected in ZnPP-treated macrophages elicited by LPS according to Western and immunoprecipitation/Western blotting assays, respectively. The decrease in LPS-induced iNOS protein by ZnPP was reversed by adding the proteasome inhibitors MG132 and lactacystin. The reduction in HO-1 protein induced by ZnPP via transfection of HO-1 small interfering RNA did not affect the inhibitory effect of ZnPP against LPS-induced iNOS/NO production and protein ubiquitination induced by ZnPP in macrophages. Data of the present study provide the first evidence to support ZnPP effectively inhibiting inflammatory iNOS/NO production through activation of protein ubiquitination in a HO-1-independent manner in macrophages.

Chow, J.-M. [Section of Hematology-Oncology, Department of Internal Medicine, Taipei Municipal Wan Fang Hospital, Taipei Medical University, Taipei 110, Taiwan (China); Lin, H.-Y.; Shen, S.-C. [Graduate Institute of Medical Sciences, Taipei Medical University, Taipei 110, Taiwan (China); Wu, M.-S. [Department of Gastroenterology, Taipei Medical University Wan Fang Hospital, Taiwan (China); Lin, C.-W. [Graduate Institute of Pharmacy, School of Pharmacy, Taipei Medical University, Taipei 110, Taiwan (China); Chiu, W.-T. [Department of Neurosurgery, Taipei Medical University-Wan Fang Hospital, Taipei, Taiwan (China); Lin, C.-H. [Graduate Institute of Medical Sciences, Taipei Medical University, Taipei 110, Taiwan (China)], E-mail: chlin@tmu.edu.tw; Chen, Y.-C. [Graduate Institute of Medical Sciences, Taipei Medical University, Taipei 110, Taiwan (China); Cancer Research Center and Orthopedics Research Center, Taipei Medical University Hospital, Taipei, Taiwan (China)], E-mail: yc3270@tmu.edu.tw

2009-06-15

192

Inhibitory activity of nitric oxide production in RAW 264.7 cells of daldinals A–C from the fungus Daldinia childiae and other metabolites isolated from inedible mushrooms  

Microsoft Academic Search

Three benzophenone derivatives, daldinals A–C, from the Japanese fungus Daldinia childiae were evaluated for their inhibitory activity of nitric oxide (NO) production stimulated by lipopolysaccharide (LPS) in RAW\\u000a 264.7 cells. They strongly suppressed the LPS-induced production of NO with IC50 values of 15.2, 4.6 and 6.4 ?M, respectively. To clarify the mechanism involved, total RNA extraction, followed by reverse-transcribed,\\u000a polymerase chain

Dang Ngoc Quang; Liva Harinantenaina; Takashi Nishizawa; Toshihiro Hashimoto; Chie Kohchi; Gen-Ichiro Soma; Yoshinori Asakawa

2006-01-01

193

Methanol extract of Ficus leaf inhibits the production of nitric oxide and proinflammatory cytokines in LPS-stimulated microglia via the MAPK pathway.  

PubMed

Excessive production of inflammatory mediators, nitric oxide (NO) and proinflammatory cytokines from activated microglia has been implicated in neurodegeneration in human brain diseases. Recently, it seems possible that treatment with antiinflammatory agents, including Oriental medicinal plants, might delay the progression of neurodegeneration through the inhibition of microglial activation. The present study evaluated the effect of a methanol extract of Ficus religiosa leaf (MFL) on lipopolysaccharide (LPS)-induced production of NO and proinflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha), interleukin-beta (IL-1beta) and IL-6 in BV-2 cells, a mouse microglial line. MFL inhibited LPS-induced production of NO and proinflammatory cytokines in a dose-dependent manner. MFL also attenuated the expression of mRNA and proteins of inducible nitric oxide synthase (iNOS) and proinflammatory cytokines, suggesting the blockage of transcription levels, respectively. The molecular mechanism of MFL-mediated attenuation underlies the down-regulation of the extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK) signaling pathway, and suppresses the nuclear factor kappaB (NF-kappaB) activation. The results suggest that MFL exhibits antiinflammatory properties in LPS-induced activation of BV2 microglial cells, and that might have a therapeutic potential for various neurodegenerative diseases. PMID:18546149

Jung, Hyo Won; Son, Hye Young; Minh, Chau Van; Kim, Young Ho; Park, Yong-Ki

2008-08-01

194

U-Bang-Haequi Tang: A Herbal Prescription that Prevents Acute Inflammation through Inhibition of NF-?B-Mediated Inducible Nitric Oxide Synthase.  

PubMed

Since antiquity, medical herbs have been prescribed for both treatment and preventative purposes. Herbal formulas are used to reduce toxicity as well as increase efficacy in traditional Korean medicine. U-bang-haequi tang (UBT) is a herbal prescription containing Arctii fructus and Forsythia suspensa as its main components and has treated many human diseases in traditional Korean medicine. This research investigated the effects of UBT against an acute phase of inflammation. For this, we measured induction of nitric oxide (NO) and related proteins in macrophage cell line stimulated by lipopolysaccharide (LPS). Further, paw swelling was measured in carrageenan-treated rats. Carrageenan significantly induced activation of inflammatory cells and increases in paw volume, whereas oral administration of 0.3 or 1?g/kg/day of UBT inhibited the acute inflammatory response. In RAW264.7 cells, UBT inhibited mRNA and protein expression levels of iNOS. UBT treatment also blocked elevation of NO production, nuclear translocation of NF-?B, phosphorylation of I?-B? induced by LPS. Moreover, UBT treatment significantly blocked the phosphorylation of p38 and c-Jun NH2-terminal kinases by LPS. In conclusion, UBT prevented both acute inflammation in rats as well as LPS-induced NO and iNOS gene expression through inhibition of NF-?B in RAW264.7 cells. PMID:24959187

Hwangbo, Min; Jung, Ji Yun; Ki, Sung Hwan; Park, Sang Mi; Jegal, Kyung Hwan; Cho, Il Je; Lee, Ju-Hee; Kang, Seung Ho; Park, Sun-Dong; Ku, Sae Kwang; Kim, Sang Chan; Zhao, Rong Jie; Jee, Seon Young; Kim, Young Woo

2014-01-01

195

Supercritical extract of Seabuckthorn Leaves (SCE200ET) inhibited endotoxemia by reducing inflammatory cytokines and nitric oxide synthase 2 expression.  

PubMed

Endotoxins from infectious organisms lead to sepsis, a systemic inflammatory response, and a major cause of death. Numerous studies have shown the potential role of plants and plant-derived compounds in the suppression of LPS induced endotoxemia in vivo. In the present study, we have identified a plant namely Seabuckthorn (Hippophae rhamnoides L.) as a potent agent for the treatment of endotoxemia. The objective of the study was to investigate the influence of Supercritical Extract of Seabuckthorn Leaves (SCE200ET) and its active component Isorhamnetin (IR) on the LPS induced endotoxemia in Balb/c mice by measuring the level of nitric oxide (NO), TNF-? and IL-6. Expression of COX-2 and iNOS was measured to understand the involvement of various pathways in the mechanism of action of SCE200ET and IR. The results indicated that SCE200ET and IR inhibited LPS induced NO production by peritoneal macrophages. Cytokines mediated effector functions were influenced by the reduction of IL-6 and TNF-? production and CD40 expression was also markedly diminished in the extract or IR treated groups. In addition, the anti-inflammatory properties were further characterized by decreased expression of COX-2 and iNOS proteins. Fractionation and phytochemical analysis of the extract by RP-HPLC led to identification of isorhamnetin, as bioactive component. Thus, SCE200ET extract and its active component Isorhamnetin could be potential therapeutic agents for the treatment of endotoxin induced sepsis. PMID:24594274

Jayashankar, Bindhya; Mishra, K P; Ganju, L; Singh, S B

2014-05-01

196

UV Induced Oxidation of Nitric Oxide  

NASA Technical Reports Server (NTRS)

Nitric oxide in a gaseous stream is converted to nitrogen dioxide using oxidizing species generated at least in part using in situ UV radiation sources. The sources of the oxidizing species include oxygen and/or hydrogen peroxide. The oxygen may be a component of the gaseous stream or added to the gaseous stream, preferably near a UV radiation source, and is converted to ozone by the UV irradiation. The hydrogen peroxide is decomposed through a combination of vaporization and UV irradiation. The hydrogen peroxide is preferably stored at stable concentration levels, i.e., approximately 50% by volume and increased in concentration in a continuous process preceding vaporization within the flow channel of the gaseous stream and in the presence of the UV radiation sources.

Parrish, Clyde, F. (Inventor); Luecke, Dale E. (Inventor)

2007-01-01

197

Nitric oxide and MPP + -induced hydroxyl radical generation  

Microsoft Academic Search

Summary.  Although neuroprotective effect of nitric oxide (NO) is discussed, NO has a role of pathogenesis of cellular injury. NO is\\u000a synthesized from L-arginine by NO synthase (NOS). NO contributes to the extracellular potassium-ion concentration ([K+]o)-induced hydroxyl radical (•OH) generation. Cytotoxic free radicals such as peroxinitrite (ONOO?) and •OH may also be implicated in NO-mediated cell injury. NO activation was induced

T. Obata

2006-01-01

198

Avicularin Inhibits Lipopolysaccharide-Induced Inflammatory Response by Suppressing ERK Phosphorylation in RAW 264.7 Macrophages  

PubMed Central

suppresAvicularin, quercetin-3-?-L-arabinofuranoside, has been reported to possess diverse pharmacological properties such as anti-inflammatory and anti-infectious effects. However, the underlying mechanism by which avicularin exerts its anti-inflammatory activity has not been clearly demonstrated. This study aimed to elucidate the anti-inflammatory mechanism of avicularin in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. Avicularin significantly inhibited LPS-induced excessive production of pro-inflammatory mediators such as nitric oxide (NO) and PGE2 and the protein levels of iNOS and COX-2, which are responsible for the production of NO and PGE2, respectively. Avicularin also suppressed LPS-induced overproduction of pro-inflammatory cytokine IL-1?. Furthermore, avicularin significantly suppressed LPS-induced degradation of I?B, which retains NF-?B in the cytoplasm, consequently inhibiting the transcription of pro-inflammatory genes by NF-?B in the nucleus. To understand the underlying signaling mechanism of anti-inflammatory activity of avicularin, involvement of multiple kinases was examined. Avicularin significantly attenuated LPS-induced activation of ERK signaling pathway in a concentration-dependent manner. Taken together, the present study clearly demonstrates that avicularin exhibits anti-inflammatory activity through the suppression of ERK signaling pathway in LPS-stimulated RAW 264.7 macrophage cells. PMID:24009846

Vo, Van Anh; Lee, Jae-Won; Chang, Ji-Eun; Kim, Ji-Young; Kim, Nam-Ho; Lee, Hee Jae; Kim, Sung-Soo; Chun, Wanjoo; Kwon, Yong-Soo

2012-01-01

199

Altered immune responses in mice lacking inducible nitric oxide synthase  

Microsoft Academic Search

NITRIC oxide (NO) is important in many biological functions1-5. It is generated from L-arginine by the enzyme NO synthase (NOS). The cytokine-inducible NOS (iNOS) is activated by several immunological stimuli, leading to the production of large quantities of NO which can be cytotoxic6. To define the biological role of iNOS further, we generated iNOS mutant mice. These are viable, fertile

Xiao-Qing Wei; I. G. Charles; Austin Smith; Jan Ure; Gui-Jie Feng; Fang-Ping Huang; Damo Xu; W. Muller; Salvador Moncada

1995-01-01

200

Mycoepoxydiene Inhibits Lipopolysaccharide-Induced Inflammatory Responses through the of TRAF6 Polyubiquitination  

PubMed Central

Mycoepoxydiene (MED) is a polyketide isolated from a marine fungus associated with mangrove forests. MED has been shown to be able to induce cell cycle arrest and cancer cell apoptosis. However, its effects on inflammatory response are unclear. Herein we showed that MED exhibited inhibitory effect on inflammatory response induced by lipopolysaccharide (LPS). MED significantly inhibited LPS-induced expression of pro-inflammatory mediators such as tumor necrosis factor-? (TNF-?), interleukin (IL)-1?, IL-6, and nitric oxide (NO) in macrophages. MED inhibited LPS-induced nuclear translocation of nuclear factor (NF)-?B (NF-?B) p65, I?B degradation, I?B kinase (IKK) phosphorylation, and the activation of extracellular signal-regulated kinase (ERK), c-jun N-terminal kinase (JNK), and p38, suggesting that MED blocks the activation of both NF-?B and mitogen-activated protein kinase (MAPK) pathways. Furthermore, the effects of MED on LPS-induced activation of upstream signaling molecules such as transforming growth factor-?–activated kinase 1 (TAK1), tumor necrosis factor receptor-associated factor 6 (TRAF6) and IL-1 receptor associated kinases1 (IRAK1) were investigated. MED significantly inhibited TAK1 phosphorylation and TRAF6 polyubiquitination, but not IRAK1 phosphorylation and TRAF6 dimerization, indicating that MED inhibits LPS-induced inflammatory responses at least in part through suppression of TRAF6 polyubiquitination. Moreover, MED protected mice from LPS-induced endotoxin shock by reducing serum inflammatory cytokines. These results suggest that MED is a potential lead compound for the development of a novel nonsteroidal anti-inflammatory drug. PMID:22984582

Li, Wenjiao; Zhang, Wei; Zhu, Jingwei; Li, Yang; Huang, Yaojian; Shen, Yuemao; Yu, Chundong

2012-01-01

201

Oral Administration of 2 -Docosahexaenoyl Lysophosphatidylcholine Displayed Anti-Inflammatory Effects on Zymosan A-Induced Peritonitis  

Microsoft Academic Search

Lysophosphatidylcholines (lysoPCs) have been known to be bioactive lipid mediators, which take part in various biological\\u000a and pathological processes. In the present study, we examined the anti-inflammatory actions of 2-docosahexaenoyl lysophosphatidylcholine (2-docosahexaenoyl-lysoPC) in vitro as well as in vivo systems. When RAW 264.7 cells were treated with 2-docoshexaenoyl-lysoPC, a concentration-dependent decrease of LPS-induced formation of nitric oxide (NO), tumor necrosis

Nguyen Dang Hung; Mee Ree Kim; Dai-Eun Sok

2011-01-01

202

Exercise training reverses age-induced inducible nitric oxide synthase upregulation  

E-print Network

an inflammatory response and may contribute to an exercise-induced rise of endogenous nitric oxide production. Similarly, acute exercise consisting of an incremental treadmill test followed by a continuous run until exhaustion at 110% of the individual anaerobic... an inflammatory response and may contribute to an exercise-induced rise of endogenous nitric oxide production. Similarly, acute exercise consisting of an incremental treadmill test followed by a continuous run until exhaustion at 110% of the individual anaerobic...

Song, Wook

2005-02-17

203

Yu Ping Feng San, an Ancient Chinese Herbal Decoction, Regulates the Expression of Inducible Nitric Oxide Synthase and Cyclooxygenase-2 and the Activity of Intestinal Alkaline Phosphatase in Cultures  

PubMed Central

Yu Ping Feng San (YPFS), a Chinese herbal decoction comprising Astragali Radix (AR; Huangqi), Atractylodis Macrocephalae Rhizoma (AMR; Baizhu), and Saposhnikoviae Radix (SR; Fangfeng), has been used clinically to treat inflammatory bowel diseases (IBD). Previously, we demonstrated a dual role of YPFS in regulating cytokine release in cultured macrophages. In this study, we elucidated the anti-inflammatory effect of YPFS that is mediated through modulating the expression of three key enzymes involved in IBD: inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and intestinal alkaline phosphatase (IALP). In a lipopolysaccharide (LPS)-induced chronic-inflammation model of cultured murine macrophages, YPFS treatment suppressed the activation of iNOS and COX-2 expression in a dose-dependent manner. Conversely, application of YPFS in cultured small intestinal enterocytes markedly induced the expression of IALP in a time-dependent manner, which might strengthen the intestinal detoxification system. A duality of YPFS in modulating the expression of iNOS and COX-2 was determined here. The expression of iNOS and COX-2 in macrophages was induced by YPFS, and this activation was partially blocked by the NF-?B-specific inhibitor BAY 11-7082, indicating a role of NF-?B signaling. These YPFS-induced changes in gene regulation strongly suggest that the anti-inflammatory effects of YPFS are mediated through the regulation of inflammatory enzymes. PMID:24967898

Du, Crystal Y. Q.; Choi, Roy C. Y.; Dong, Tina T. X.; Lau, David T. W.; Tsim, Karl W. K.

2014-01-01

204

Antioxidant properties of lutein contribute to the protection against lipopolysaccharide-induced uveitis in mice  

PubMed Central

Background Lutein is an important eye-protective nutrient. This study investigates the protective effects and mechanisms of lutein on lipopolysaccharides (LPS)-induced uveitis in mice. Methods Lutein, suspended in drinking water at a final concentration of 12.5 and 25 mg/mL, was administered to mice at 0.1 mL/10 g body weight for five consecutive days. Control and model group received drinking water only. Uveitis was induced by injecting LPS (100 mg per mouse) into the footpad in the model and lutein groups on day 5 after the last drug administration. Eyes of the mice were collected 24 hours after the LPS injection for the detection of indicators using commercial kits and reverse transcription-polymerase chain reaction. Results LPS-induced uveitis was confirmed by significant pathological damage and increased the nitric oxide level in eye tissue of BALB/C mice 24 hours after the footpad injection. The elevated nitric oxide level was significantly reduced by oral administration of lutein (125 and 500 mg/kg/d for five days) before LPS injection. Moreover, lutein decreased the malondialdehyde content, increased the oxygen radical absorbance capacity level, glutathione, the vitamin C contents and total superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities. Lutein further increased expressions of copper-zinc SOD, manganese SOD and GPx mRNA. Conclusion The antioxidant properties of lutein contribute to the protection against LPS-induced uveitis, partially through the intervention of inflammation process. PMID:22040935

2011-01-01

205

Functional link between TNF biosynthesis and CaM-dependent activation of inducible nitric oxide synthase in RAW 264.7 macrophages  

SciTech Connect

Inflammatory responses stimulated by bacterial endotoxin (lipopolysaccharide, LPS) involve calcium-mediated signaling, yet the cellular sensors that determine cell fate in response to LPS remain poorly understood. We report that exposure of RAW 264.7 macrophage-like cells to LPS induces a rapid increase in calmodulin (CaM) abundance, which is associated with the modulation of the inflammatory response. Increases in CaM abundance precedes nuclear localization of key transcription factors (i.e., NF?B p65 subunit, phospho-c-Jun, and Sp1) and subsequent increases in the pro-inflammatory cytokine tumor necrosis factor ? (TNF) and inducible nitric oxide synthase (iNOS). Cellular apoptosis following LPS challenge is blocked following inhibition of iNOS activity, whether accomplished using the pharmacological inhibitor 1400W, through gene silencing of TNF?, or by increasing the level of cellular CaM by stable transfection. Increasing CaM expression also results in reductions in the cellular release of TNF? and iNOS, and activation of their transcriptional regulators, indicating the level of available CaM plays a key role in determining the expression of the pro-inflammatory and pro-apoptotic cascade during cellular activation by LPS. These results indicate a previously unrecognized central role for CaM in maintaining cellular homeostasis in response to LPS, such that under resting conditions cellular concentrations of CaM are sufficient to inhibit the biosynthesis of proinflammatory mediators associated with macrophage activation. Although CaM and iNOS protein levels are coordinately increased as part of the oxidative burst, limiting cellular concentrations of CaM due to association with iNOS (and other high-affinity binders) commit the cell to an unchecked inflammatory cascade leading to apoptosis.

Weber, Thomas J.; Smallwood, Heather S.; Kathmann, Loel E.; Markillie, Lye MENG.; Squier, Thomas C.; Thrall, Brian D.

2006-01-18

206

Inducible nitric oxide synthase--time for reappraisal.  

PubMed

Inducible nitric oxide synthase (iNOS) is one of three key enzymes generating nitric oxide (NO) from the amino acid L-arginine. iNOS-derived NO plays an important role in numerous physiological and pathophysiological conditions, e.g. blood pressure regulation, inflammation, infection, and the onset and progression of malignant diseases. iNOS has been conjectured both as a marker and a therapeutic target in these situations. iNOS is a mediator of unspecific host defence, central in the clearance of bacterial, viral, fungal and parasitic infections. However, excess production of NO appears to be linked to tissue damage and organ dysfunction, e.g. the hypotensive and vasoplegic state characteristic for septic shock. However, the use of iNOS-inhibitors in septic patients should be performed carefully with regard to the essential functions and properties of NO in blood pressure/blood flow regulation. Considering iNOS-derived NO as a multifactorial transmitter of tumorigenesis and tumor progression, it is tempting to speculate on therapeutical interference with iNOS activity, especially in tumors where metastatic activity, host denfence mechanisms and the level of differentiation seem to be correlated to iNOS expression. It is the aim of this review to provide basic insights into the NOS family of enzymes as well as their regulation. In the second part of the review, we will point out the pivotal roles NOS play in inflammation and neoplastic diseases. PMID:14561209

Lirk, Philipp; Hoffmann, Georg; Rieder, Josef

2002-03-01

207

Inducible Nitric Oxide Synthase Expression in Human Colorectal Cancer  

PubMed Central

To investigate the potential involvement of the nitric oxide (NO) pathway in colorectal carcinogenesis, we correlated the expression and the activity of inducible nitric oxide synthase (iNOS) with the degree of tumor angiogenesis in human colorectal cancer. Tumor samples and adjacent normal mucosa were obtained from 46 surgical specimens. Immunohistochemical expression of iNOS, vascular endothelial growth factor (VEGF), and CD31 was analyzed on paraffin-embedded tissue sections. iNOS activity and cyclic GMP levels were assessed by specific biochemical assays. iNOS protein expression was determined by Western blot analysis. iNOS and VEGF mRNA levels were evaluated using Northern blot analysis. Both iNOS and VEGF expressions correlated significantly with intratumor microvessel density (rs = 0.31, P = 0.02 and rs = 0.67, P < 0.0001, respectively). A significant correlation was also found between iNOS and VEGF expression (P = 0.001). iNOS activity and cyclic GMP production were significantly higher in the cancer specimens than in the normal mucosa (P < 0.0001 and P < 0.0001, respectively), as well as in metastatic tumors than in nonmetastatic ones (P = 0.002 and P = 0.04, respectively). Western and Northern blot analyses confirmed the up-regulation of the iNOS protein and gene in the tumor specimens as compared with normal mucosa. NO seems to play a role in colorectal cancer growth by promoting tumor angiogenesis. PMID:12598314

Cianchi, Fabio; Cortesini, Camillo; Fantappie, Ornella; Messerini, Luca; Schiavone, Nicola; Vannacci, Alfredo; Nistri, Silvia; Sardi, Iacopo; Baroni, Gianna; Marzocca, Cosimo; Perna, Federico; Mazzanti, Roberto; Bechi, Paolo; Masini, Emanuela

2003-01-01

208

Oxidized low density lipoprotein suppresses lipopolysaccharide-induced inflammatory responses in microglia: Oxidative stress acts through control of inflammation  

SciTech Connect

Low density lipoprotein (LDL) is readily oxidized under certain conditions, resulting in the formation of oxidized LDL (oxLDL). Despite numerous in vitro reports that reveal the pathogenic role of oxidative stress, anti-oxidative strategies have underperformed in the clinic. In this study, we examine the role of oxLDL in brain inflammatory responses using cultured rat brain microglia. We demonstrate that oxLDL inhibits lipopolysaccharide (LPS)-induced inflammatory responses in these cells. It also decreases LPS-induced expression of inducible nitric oxide synthase and production of nitric oxide, and reduces LPS-induced secretion of tumor necrosis factor-{alpha} and monocyte chemoattractant protein-1. Oxysterols, known components of oxLDL and endogenous agonists of liver X receptor, can simulate the inhibitory effects of oxLDL in LPS-activated microglia. In addition, their inhibitory effects were mimicked by liver X receptor (LXR) agonists and potentiated by a retinoid X receptor agonist, suggesting these molecules heterodimerize to function as oxysterol receptors. Taken together, our results demonstrate that oxLDL inhibits LPS-induced inflammatory responses in brain microglia and that these inhibitory effects are mediated by oxysterols and, at least in part, by the nuclear receptor LXR. Our results suggest an additional mechanism of action for oxidative stress that acts indirectly via modulation of inflammatory responses. Although further studies are needed, these results answer in part the question of why anti-oxidative strategies have not been successful in clinical situations. Moreover, as brain inflammation participates in the initiation and progression of several neurodegenerative disorders, the present data provide information that should prove a useful guide for designing therapeutic strategies to combat oxidative brain diseases.

Kim, Ohn Soon [Department of Pharmacology, Ajou University School of Medicine, San 5, Wonchen-Dong, Youngtong-Gu, Gyunggi-Do, Suwon 442-721 (Korea, Republic of); Chronic Inflammatory Disease Research Center, Ajou University School of Medicine, Suwon (Korea, Republic of); Lee, Chang Seok [Department of Pharmacology, Ajou University School of Medicine, San 5, Wonchen-Dong, Youngtong-Gu, Gyunggi-Do, Suwon 442-721 (Korea, Republic of); Chronic Inflammatory Disease Research Center, Ajou University School of Medicine, Suwon (Korea, Republic of); Joe, Eun-hye [Department of Pharmacology, Ajou University School of Medicine, San 5, Wonchen-Dong, Youngtong-Gu, Gyunggi-Do, Suwon 442-721 (Korea, Republic of); Jou, Ilo [Department of Pharmacology, Ajou University School of Medicine, San 5, Wonchen-Dong, Youngtong-Gu, Gyunggi-Do, Suwon 442-721 (Korea, Republic of) and Chronic Inflammatory Disease Research Center, Ajou University School of Medicine, Suwon (Korea, Republic of)]. E-mail: jouilo@ajou.ac.kr

2006-03-31

209

Endotoxin impairs biliary glutathione and HCO3- excretion and blocks the choleretic effect of nitric oxide in rat liver.  

PubMed

Cholestasis in patients with sepsis has been attributed to the effects of endotoxin (lipopolysaccharides, LPS) and LPS-induced cytokines, which are also potent stimulators of systemic and hepatic nitric oxide (NO) synthesis. NO donors stimulate bile acid-independent bile flow in normal rat liver, but the effects of LPS-induced NO on bile formation remain unclear. To address this question we examined the effects of NO and its mediator guanosine 3',5'-cyclic monophosphate (cGMP) on bile flow and biliary HCO3- and glutathione excretion in isolated perfused rat livers (IPRL) from LPS-treated rats. Portal and systemic NO2- + NO3- plasma levels were increased 47-fold in LPS-treated rats and were also elevated in perfusate (6-fold) and bile (9-fold) after isolating and perfusing livers from these animals. Bile flow, HCO3-, and glutathione output were decreased by 33%, 25%, and 81% in these IPRL, respectively. Stimulation of NO synthesis with L-arginine or inhibition of inducible NO synthesis with aminoguanidine did not change bile flow, although pretreatment with aminoguanidine inhibited NO production by 85%. Moreover, the choleretic effects of infusions of the NO donors sodium nitroprusside (SNP) and S-nitroso-acetyl-penicillamine were markedly reduced in endotoxemic IPRL compared with normal controls, and SNP-induced HCO3- and glutathione excretion were reduced by 61% and 86%, respectively. SNP-induced cyclic GMP production was 2.3-fold lower than in normals, but the choleretic effect of dibutyryl cGMP was only slightly reduced in endotoxemic livers. These findings indicate that LPS reduces bile acid-independent bile flow primarily by inhibiting biliary excretion of glutathione and to a lesser extent HCO3-, whereas LPS-induced NO does not modulate bile formation in endotoxemia. Thus, impairment of the major determinants of bile acid-independent bile flow by LPS may contribute significantly to the pathogenesis of the cholestasis of sepsis. PMID:9141437

Trauner, M; Nathanson, M H; Rydberg, S A; Koeppel, T A; Gartung, C; Sessa, W C; Boyer, J L

1997-05-01

210

MEMANTINE PROTECTS AGAINST LPS-INDUCED NEUROINFLAMMATION, RESTORES BEHAVIORALLY-INDUCED GENE  

E-print Network

, autism, Down syndrome, HIV de- mentia, and demyelinating diseases, such as multiple scle- rosis, and Aging, University of Arizona, Tucson, AZ 85724, USA b Cognitive Neuroscience Center and Department of neuroinflammation-influenced diseases may confer neural and cognitive protection. © 2006 IBRO. Pub- lished

Wenk, Gary

211

Cytotoxicity induced by grape seed proanthocyanidins: role of nitric oxide.  

PubMed

Grape seed proanthocyanidin extract (GPSE) at high doses has been shown to exhibit cytotoxicity that is associated with increased apoptotic cell death. Nitric oxide (NO), being a regulator of apoptosis, can be increased in production by the administration of GSPE. In a chick cardiomyocyte study, we demonstrated that high-dose (500 microg/ml) GSPE produces a significantly high level of NO that contributes to increased apoptotic cell death detected by propidium iodide and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining. It is also associated with the depletion of intracellular glutathione (GSH), probably due to increased consumption by NO with the formation of S-nitrosoglutathione. Co-treatment with L-NAME, a NO synthase inhibitor, results in reduction of NO and apoptotic cell death. The decline in reduced GSH/oxidized GSH (GSSG) ratio is also reversed. N-Acetylcysteine, a thiol compound that reacts directly with NO, can reduce the increased NO generation and reverse the decreased GSH/GSSG ratio, thereby attenuating the cytotoxicity induced by high-dose GSPE. Taken together, these results suggest that endogenous NO synthase (NOS) activation and excessive NO production play a key role in the pathogenesis of high-dose GSPE-induced cytotoxicity. PMID:16555001

Shao, Z H; Hsu, C W; Chang, W T; Waypa, G B; Li, J; Li, D; Li, C Q; Anderson, T; Qin, Y; Schumacker, P T; Becker, L B; Hoek, T L Vanden

2006-05-01

212

Activated protein C suppresses adrenomedullin and ameliorates lipopolysaccharide-induced hypotension.  

PubMed

Activated protein C (APC) is an important modulator of vascular function that has antithrombotic and anti-inflammatory properties. Studies in humans have shown modulation of endotoxin-induced hypotension by recombinant human APC, drotrecogin alfa (activated), however, the mechanism for this effect is unclear. We have found that APC suppresses the induction of the potent vasoactive peptide adrenomedullin (ADM) and could downregulate lipopolysaccharide (LPS)-induced ADM messenger RNA (mRNA) and nitrite levels in cell culture. This effect was dependent on signaling through protease-activated receptor 1. Addition of 1400W, an irreversible inducible nitric oxide synthase (iNOS) inhibitor, inhibited LPS-induced ADM mRNA, suggesting that ADM induction is NO mediated. Furthermore, in a rat model of endotoxemia, APC (100 microg/kg, i.v.) prevented LPS (10 mg/kg, i.v.)-induced hypotension, and suppressed ADM mRNA and protein expression. APC also inhibited iNOS mRNA and protein levels along with reduction in NO by-products (NOx). We also observed a significant reduction in iNOS-positive leukocytes adhering to vascular endothelium after APC treatment. Moreover, we found that APC inhibited the expression of interferon-gamma (IFN-gamma), a potent activator of iNOS. In a human study of LPS-induced hypotension, APC reduced the upregulation of plasma ADM levels, coincident with protection against the hypotensive response. Overall, we demonstrate that APC blocks the induction of ADM, likely mediated by IFN-gamma and iNOS, and suggests a mechanism that may account for ameliorating LPS-induced hypotension. Furthermore, our data provide a new understanding for the role of APC in modulating vascular response to insult. PMID:17558353

Gupta, Akanksha; Berg, David T; Gerlitz, Bruce; Richardson, Mark A; Galbreath, Elizabeth; Syed, Samreen; Sharma, Avadhesh C; Lowry, Stephen F; Grinnell, Brian W

2007-10-01

213

The Function of Nitric Oxide in Wound Repair: Inhibition of Inducible Nitric Oxide-Synthase Severely Impairs Wound Reepithelialization  

Microsoft Academic Search

Recently, we demonstrated a large induction of inducible nitric oxide synthase (iNOS) during cutaneous wound repair. In this study, we established an in vivo model in mice to investigate the role of NO during the wound healing process. During excisional repair, mice were treated with L-N6-(1-iminoethyl)lysine (L-NIL), a selective inhibitor of iNOS enzymatic activity. Compared with control mice, L-NIL-treated animals

Birgit Stallmeyer; Heiko Kämpfer; Nicole Kolb; Josef Pfeilschifter; Stefan Frank

1999-01-01

214

PRIOR LAPAROTOMY OR CORTICOSTERONE POTENTIATES LIPOPOLYSACCHARIDE-INDUCED FEVER AND SICKNESS BEHAVIORS  

PubMed Central

Stimulating sensitized immune cells with a subsequent immune challenge results in potentiated pro-inflammatory responses translating into exacerbated sickness responses (i.e. fever, pain and lethargy). Both corticosterone (CORT) and laparotomy cause sensitization, leading to enhanced sickness-induced neuroinflammation or pain (respectively). However, it is unknown whether this sensitization affects all sickness behaviors and immune cell responses equally. We show that prior CORT and prior laparotomy potentiated LPS-induced fever but not lethargy. Prior CORT, like prior laparotomy, was able to potentiate sickness-induced pain. Release of nitric oxide (NO) from peritoneal macrophages stimulated ex vivo demonstrates that laparotomy, but not CORT sensitizes these cells. PMID:21907418

Hains, Leah E.; Loram, Lisa C.; Taylor, Frederick R; Strand, Keith A; Wieseler, Julie L.; Barrientos, Ruth M.; Young, Jennifer J.; Frank, Matthew G; Sobesky, Julia; Martin, Thomas J.; Eisenach, James C.; Maier, Steven F.; Johnson, John D.; Fleshner, Monika; Watkins, Linda R.

2011-01-01

215

Nitric oxide induces cell death in Taxus cells.  

PubMed

Sodium nitroprusside (SNP), a nitric oxide donor, or centrifugation at 150 times unit gravity, caused a nitric oxide burst in oocyte-derived Taxus brevifolia haploid cultures. This burst, visualized by the specific fluorescent probe 4,5-diaminofluorescein diacetate (DAF-2 DA), preceded a significant increase in nuclear DNA fragmentation and cell death. DNA fragmentation was detected in situ by the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) of DNA 3'-OH groups. Nitric oxide formation and cell death were significantly decreased by N(G)-monomethyl-L-arginine (L-NMMA), a nitric oxide-synthase (NOS; EC 1.14.13.39) inhibitor. Our results show that nitric oxide leads to irreversible DNA fragmentation and cell death under stressful conditions, and that its effect can be prevented by L-NMMA. PMID:10960730

Pedroso; Magalhaes; Durzan

2000-08-22

216

Short Communication The nitric oxide synthase inhibitor l-NAME suppresses androgen-induced  

E-print Network

Short Communication The nitric oxide synthase inhibitor l-NAME suppresses androgen-induced male anesthesia and each implanted with a Silastic tube (Helix Medical, 10 mm long, internal diameter 1.47 mm

Crews, David

217

In vivo Expression of Inducible Nitric Oxide Synthase in Experimentally Induced Neurologic Diseases  

NASA Astrophysics Data System (ADS)

The purpose of this study was to investigate the induction of inducible nitric oxide synthase (iNOS) mRNA in the brain tissue of rats and mice under the following experimental conditions: in rats infected with borna disease virus and rabies virus, in mice infected with herpes simplex virus, and in rats after the induction of experimental allergic encephalitis. The results showed that iNOS mRNA, normally nondetectable in the brain, was present in animals after viral infection or after induction of experimental allergic encephalitis. The induction of iNOS mRNA coincided with the severity of clinical signs and in some cases with the presence of inflammatory cells in the brain. The results indicate that nitric oxide produced by cells induced by iNOS may be the toxic factor accounting for cell damage and this may open the door to approaches to the study of the pathogenesis of neurological diseases.

Koprowski, Hilary; Zheng, Yong Mu; Heber-Katz, Ellen; Fraser, Nigel; Rorke, Lucy; Fu, Zhen Fang; Hanlon, Cathleen; Dietzschold, Bernhard

1993-04-01

218

IL-1 Mediates Pulmonary and Systemic Inflammatory Responses to Chorioamnionitis Induced by Lipopolysaccharide  

PubMed Central

Rationale: Chorioamnionitis frequently associates with preterm delivery and increased amniotic fluid IL-1, and causes fetal lung and systemic inflammation. However, chorioamnionitis is also associated with a paradoxical reduction in the incidence of surfactant deficiency–related respiratory distress syndrome in preterm infants. Objectives: To identify the role of IL-1 signaling in the mediation of pulmonary and systemic inflammation and lung maturation in a fetal sheep model of lipopolysaccharide (LPS) induced chorioamnionitis. Methods: After confirming the efficacy of recombinant human IL-1 receptor antagonist (rhIL-1ra), fetal sheep were exposed to intraamniotic (IA) injections of Escherichia coli LPS with or without prior IA injections of rhIL-1ra. Preterm lambs were delivered at 82% of term gestation. Measurements and Main Results: rhIL-1ra decreased IA LPS–induced lung inflammation assessed by decreased lung neutrophil and monocyte influx, inducible nitric oxide synthase expression, lung IL-6 and IL-1? mRNA expression, and airway myeloperoxidase concentrations. rhIL-1ra inhibited IA LPS–induced fetal systemic inflammation assessed by decreased plasma IL-8, protein carbonyls, blood neutrophilia, and the expression of serum amyloid A3 mRNA in the liver. rhIL-1ra also partially blocked the lung maturational effects of IA LPS. Therefore blockade of IL-1 signaling in the amniotic compartment inhibited fetal lung and systemic inflammation and lung maturation in response to LPS-induced chorioamnionitis. Conclusions: IL-1 plays a central role in the pathogenesis of chorioamnionitis-induced fetal inflammatory responses. PMID:19234101

Kallapur, Suhas G.; Nitsos, Ilias; Moss, Timothy J. M.; Polglase, Graeme R.; Pillow, J. Jane; Cheah, Fook-Choe; Kramer, Boris W.; Newnham, John P.; Ikegami, Machiko; Jobe, Alan H.

2009-01-01

219

Nitric oxide-mediated hyporeactivity to noradrenaline precedes the induction of nitric oxide synthase in endotoxin shock.  

PubMed Central

1. The role of an enhanced formation of nitric oxide (NO) and the relative importance of the constitutive and inducible NO synthase (NOS) for the development of immediate (within 60 min) and delayed (at 180 min) vascular hyporeactivity to noradrenaline was investigated in a model of circulatory shock induced by endotoxin (lipopolysaccharide; LPS) in the rat. 2. Male Wistar rats were anaesthetized and instrumented for the measurement of mean arterial blood pressure (MAP) and heart rate. In addition, the calcium-dependent and calcium-independent NOS activity was measured ex vivo by the conversion of [3H]-arginine to [3H]-citrulline in homogenates from several organs obtained from vehicle- and LPS-treated rats. 3. E. coli LPS (10 mg kg-1, i.v. bolus) caused a rapid (within 5 min) and sustained fall in MAP. At 30 and 60 min after LPS, pressor responses to noradrenaline (0.3, 1 or 3 micrograms kg-1, i.v.) were significantly reduced. The pressor responses were restored by NG-nitro-L-arginine methyl ester (L-NAME, 1 mg kg-1, i.v. at 60 min), a potent inhibitor of NO synthesis. In contrast, L-NAME did not potentiate the noradrenaline-induced pressor responses in control animals. 4. Dexamethasone (3 mg kg-1, i.v., 60 min prior to LPS), a potent inhibitor of the induction of NOS, did not alter initial MAP or pressor responses to noradrenaline in control rats, but significantly attenuated the LPS-induced fall in MAP at 15 to 60 min after LPS. Dexamethasone did not influence the development of the LPS-induced immediate (within 60 min) hyporeactivity to noradrenaline.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7682137

Szabó, C.; Mitchell, J. A.; Thiemermann, C.; Vane, J. R.

1993-01-01

220

Methyl p-Hydroxycinnamate Suppresses Lipopolysaccharide-Induced Inflammatory Responses through Akt Phosphorylation in RAW264.7 Cells  

PubMed Central

Derivatives of caffeic acid have been reported to possess diverse pharmacological properties such as anti-inflammatory, anti-tumor, and neuroprotective effects. However, the biological activity of methyl p-hydroxycinnamate, an ester derivative of caffeic acid, has not been clearly demonstrated. This study aimed to elucidate the anti-inflammatory mechanism of methyl p-hydroxycinnamate in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. Methyl p-hydroxycinnamate significantly inhibited LPS-induced excessive production of pro-inflammatory mediators such as nitric oxide (NO) and PGE2 and the protein expression of iNOS and COX-2. Methyl p-hydroxycinnamate also suppressed LPS-induced overproduction of pro-inflammatory cytokines such as IL-1? and TNF-?. In addition, methyl p-hydroxycinnamate significantly suppressed LPS-induced degradation of I?B, which retains NF-?B in the cytoplasm, consequently inhibiting the transcription of pro-inflammatory genes by NF-?B in the nucleus. Methyl p-hydroxycinnamate exhibited significantly increased Akt phosphorylation in a concentration-dependent manner. Furthermore, inhibition of Akt signaling pathway with wortmaninn abolished methyl p-hydroxycinnamate-induced Akt phosphorylation. Taken together, the present study clearly demonstrates that methyl p-hydroxycinnamate exhibits anti-inflammatory activity through the activation of Akt signaling pathway in LPS-stimulated RAW264.7 macrophage cells. PMID:24596616

Vo, Van Anh; Lee, Jae-Won; Shin, Seung-Yeon; Kwon, Jae-Hyun; Lee, Hee Jae; Kim, Sung-Soo; Kwon, Yong-Soo; Chun, Wanjoo

2014-01-01

221

Therapeutic Effect of C-Phycocyanin Extracted from Blue Green Algae in a Rat Model of Acute Lung Injury Induced by Lipopolysaccharide  

PubMed Central

C-Phycocyanin (CPC), extracted from blue green algae, is a dietary nutritional supplement due to its several beneficial pharmacological effects. This study was conducted to evaluate whether CPC protects against lipopolysaccharide- (LPS-) induced acute lung injury (ALI) in rats. Rats were challenged with LPS (5?mg/kg body weight) intratracheally to induce ALI. After 3?h LPS instillation, rats were administrated with CPC (50?mg/kg body weight, i.p.) for another 3?h. Our results showed that posttreatment with CPC significantly inhibited LPS-induced elevation of protein concentration, nitrite/nitrate level, release of proinflammatory cytokines, the number of total polymorphonuclear cells in bronchoalveolar lavage fluid, and lung edema evidenced by decrease of lung wet/dry weight ratio accompanied by a remarkable improvement of lung histopathological alterations. Furthermore, CPC significantly attenuated LPS-induced myeloperoxidase activity, O2? formation, expression of inducible nitric oxide synthase, and cyclooxygenase-2 as well as nuclear factor-kappa B (NF-?B) activation in lungs. Additionally, CPC significantly downregulated proapoptotic proteins such as caspase-3 and Bax, but upregulated antiapoptotic proteins such as Bcl-2 and Bcl-XL in lungs exposed to LPS. These findings indicate that CPC could be potentially useful for treatment of LPS-related ALI by inhibiting inflammatory responses and apoptosis in lung tissues. PMID:23573157

Leung, Pak-on; Lee, Hao-Hsien; Kung, Yu-Chien; Tsai, Ming-Fan; Chou, Tz-Chong

2013-01-01

222

Modified peptide nucleic acids are internalized in mouse macrophages RAW 264.7 and inhibit inducible nitric oxide synthase  

Microsoft Academic Search

Overexpression of inducible nitric oxide synthase causes the production of high levels of nitric oxide, which, under pathological conditions, leads to immunosuppression and tissue damage. The results recently obtained using peptide nucleic acids, rather than traditional oligonucleotides as antigen and antisense molecules, prompted us to test their efficacy in the regulation of nitric oxide production, thereby overcoming the obstacle of

Sonia Scarfi; Marco Giovine; Anna Gasparini; Gianluca Damonte; Enrico Millo; Marina Pozzolini; Umberto Benatti

1999-01-01

223

Self-administration of heroin produces alterations in the expression of inducible nitric oxide synthase  

Microsoft Academic Search

Nitric oxide plays a critical role in the immune response, and our studies have shown that heroin induces a reduction in the expression of iNOS, the enzyme responsible for nitric oxide production. The present study evaluated the effect of heroin self-administration on iNOS expression using a three-group design. Group one (self-administration) was trained to press a lever for i.v. administration

Ryan K. Lanier; Stephanie G. Ijames; Kelly A. Carrigan; Regina M. Carelli; Donald T. Lysle

2002-01-01

224

Ebselen and cytokine-induced nitric oxide synthase expression in insulin-producing cells  

Microsoft Academic Search

Interleukin-1 (IL-1) may be a mediator of ?-cell damage in insulin-dependent diabetes mellitus (IDDM). The IL-1 mechanism of action on insulin-producing cells probably includes activation of the transcription nuclear factor ?B (NF-?B), increased transcription of the inducible form of nitric oxide synthase (iNOS) and the subsequent production of nitric oxide (NO). Reactive oxygen intermediates, particularly H2O2, have been proposed as

Maria A. R. de-Mello; Malin Flodström; Décio L. Eizirik

1996-01-01

225

PKC412 (CGP41251) modulates the proliferation and lipopolysaccharide-induced inflammatory responses of RAW 264.7 macrophages  

SciTech Connect

PKC412 (CGP41251) is a multitarget protein kinase inhibitor with anti-tumor activities. Here, we investigated the effects of PKC412 on macrophages. PKC412 inhibited the proliferation of murine RAW 264.7 macrophages through induction of G2/M cell cycle arrest and apoptosis. At non-toxic drug concentrations, PKC412 significantly suppressed the lipopolysaccharide (LPS)-induced release of TNF-{alpha} and nitric oxide, while instead enhancing IL-6 secretion. PKC412 attenuated LPS-induced phosphorylations of MKK4 and JNK, as well as AP-1 DNA binding activities. Furthermore, PKC412 suppressed LPS-induced Akt and GSK-3{beta} phosphorylations. These results suggest that the anti-proliferative and immunomodulatory effects of PKC412 are, at least in part, mediated through its interference with the MKK4/JNK/AP-1 and/or Akt/GSK-3{beta} pathways. Since macrophages contribute significantly to the development of both acute and chronic inflammation, PKC412 may have therapeutic potential and applications in treating inflammatory and/or autoimmune diseases.

Miyatake, Katsutoshi [Department of Orthopedics, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima (Japan); Institute for Genome Research, The University of Tokushima, Tokushima (Japan); Inoue, Hiroshi [Institute for Genome Research, The University of Tokushima, Tokushima (Japan)]. E-mail: hinoue@genome.tokushima-u.ac.jp; Hashimoto, Kahoko [Department of Life and Environmental Sciences, Faculty of Engineering, Chiba Institute of Technology, Chiba (Japan); Takaku, Hiroshi [Department of Life and Environmental Sciences, Faculty of Engineering, Chiba Institute of Technology, Chiba (Japan); Takata, Yoichiro [Department of Orthopedics, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima (Japan); Nakano, Shunji [Department of Orthopedics, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima (Japan); Yasui, Natsuo [Department of Orthopedics, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima (Japan); Itakura, Mitsuo [Institute for Genome Research, The University of Tokushima, Tokushima (Japan)

2007-08-17

226

Phosphorylation of Akt Mediates Anti-Inflammatory Activity of 1-p-Coumaroyl ?-D-Glucoside Against Lipopolysaccharide-Induced Inflammation in RAW264.7 Cells  

PubMed Central

Hydroxycinnamic acids have been reported to possess numerous pharmacological activities such as antioxidant, anti-inflammatory, and anti-tumor properties. However, the biological activity of 1-p-coumaroyl ?-D-glucoside (CG), a glucose ester derivative of p-coumaric acid, has not been clearly examined. The objective of this study is to elucidate the anti-inflammatory action of CG in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells. In the present study, CG significantly suppressed LPS-induced excessive production of pro-inflammatory mediators such as nitric oxide (NO) and PGE2 and the protein expression of iNOS and COX-2. CG also inhibited LPS-induced secretion of pro-inflammatory cytokines, IL-1? and TNF-?. In addition, CG significantly suppressed LPS-induced degradation of I?B. To elucidate the underlying mechanism by which CG exerts its anti-inflammatory action, involvement of various signaling pathways were examined. CG exhibited significantly increased Akt phosphorylation in a concentration-dependent manner, although MAPKs such as Erk, JNK, and p38 appeared not to be involved. Furthermore, inhibition of Akt/PI3K signaling pathway with wortmannin significantly, albeit not completely, abolished CG-induced Akt phosphorylation and anti-inflammatory actions. Taken together, the present study demonstrates that Akt signaling pathway might play a major role in CG-mediated anti-inflammatory activity in LPS-stimulated RAW264.7 macrophage cells. PMID:24634601

Vo, Van Anh; Lee, Jae-Won; Kim, Ji-Young; Park, Jun-Ho; Lee, Hee Jae; Kim, Sung-Soo; Kwon, Yong-Soo

2014-01-01

227

Plexin-A1 is required for Toll-like receptor-mediated microglial activation in the development of lipopolysaccharide-induced encephalopathy.  

PubMed

Recent investigations have suggested that semaphorins, which are known repulsive axon guidance molecules, may play a crucial role in maintaining brain homeostasis by regulating microglial activity. Sema3A, secreted in higher amounts from injured neurons, is considered to suppress excessive inflammatory responses by inducing microglial apoptosis through its binding to Plexin-A1 receptors on activated microglia. To clarify the in vivo role of Plexin-A1-mediated signaling in lipopolysaccharide (LPS)-induced injury in mouse brain, we examined the neuroinflammatory changes initiated by LPS administration to the cerebral ventricles of wild-type (WT) and Plexin-A1-deficient (-/-) mice. WT mice administered LPS exhibited a significantly higher expression of COX-2, iNOS, IL-1? and TNF-? in the hippocampus, and a significantly greater ventricular enlargement and intracerebral infiltration of leukocytes, as compared with the saline-treated group. By contrast, Plexin-A1-/- mice administered LPS did not exhibit a significantly increased expression of COX-2, iNOS, IL-1? or TNF-? in the hippocampus as compared with the saline-treated group. Plexin-A1-/- mice administered LPS did not show significant increases in ventricle size or infiltration of leukocytes into the brain, as compared with the saline-treated group. In WT, but not in the Plexin-A1-/- primary microglia treated with LPS, Sema3A induced significantly more nitric oxide production than in the immunoglobulin G control. These results revealed the crucial role of the Sema3A-Plexin-A1 interaction in the Toll-like receptor 4-mediated signaling of the LPS-induced activation of microglia. Thus, results of the present study revealed the essential role of Plexin-A1 in the development of LPS-induced neuroinflammation in mice, suggesting the possible application of microglial control of the semaphorin-plexin signaling system to the treatment of LPS-induced encephalopathy and other psychiatric diseases associated with neuroinflammation. PMID:24604454

Ito, Takuji; Yoshida, Kenji; Negishi, Takayuki; Miyajima, Masayasu; Takamatsu, Hyota; Kikutani, Hitoshi; Kumanogoh, Atsushi; Yukawa, Kazunori

2014-05-01

228

Plexin-A1 is required for Toll-like receptor-mediated microglial activation in the development of lipopolysaccharide-induced encephalopathy  

PubMed Central

Recent investigations have suggested that semaphorins, which are known repulsive axon guidance molecules, may play a crucial role in maintaining brain homeostasis by regulating microglial activity. Sema3A, secreted in higher amounts from injured neurons, is considered to suppress excessive inflammatory responses by inducing microglial apoptosis through its binding to Plexin-A1 receptors on activated microglia. To clarify the in vivo role of Plexin-A1-mediated signaling in lipopolysaccharide (LPS)-induced injury in mouse brain, we examined the neuroinflammatory changes initiated by LPS administration to the cerebral ventricles of wild-type (WT) and Plexin-A1-deficient (?/?) mice. WT mice administered LPS exhibited a significantly higher expression of COX-2, iNOS, IL-1? and TNF-? in the hippocampus, and a significantly greater ventricular enlargement and intracerebral infiltration of leukocytes, as compared with the saline-treated group. By contrast, Plexin-A1?/? mice administered LPS did not exhibit a significantly increased expression of COX-2, iNOS, IL-1? or TNF-? in the hippocampus as compared with the saline-treated group. Plexin-A1?/? mice administered LPS did not show significant increases in ventricle size or infiltration of leukocytes into the brain, as compared with the saline-treated group. In WT, but not in the Plexin-A1?/? primary microglia treated with LPS, Sema3A induced significantly more nitric oxide production than in the immunoglobulin G control. These results revealed the crucial role of the Sema3A-Plexin-A1 interaction in the Toll-like receptor 4-mediated signaling of the LPS-induced activation of microglia. Thus, results of the present study revealed the essential role of Plexin-A1 in the development of LPS-induced neuroinflammation in mice, suggesting the possible application of microglial control of the semaphorin-plexin signaling system to the treatment of LPS-induced encephalopathy and other psychiatric diseases associated with neuroinflammation. PMID:24604454

ITO, TAKUJI; YOSHIDA, KENJI; NEGISHI, TAKAYUKI; MIYAJIMA, MASAYASU; TAKAMATSU, HYOTA; KIKUTANI, HITOSHI; KUMANOGOH, ATSUSHI; YUKAWA, KAZUNORI

2014-01-01

229

Gelam Honey Has a Protective Effect against Lipopolysaccharide (LPS)-Induced Organ Failure  

PubMed Central

Gelam honey exerts anti-inflammatory and antioxidant activities and is thought to have potent effects in reducing infections and healing wounds. The aim of this study was to investigate the effects of intravenously-injected Gelam honey in protecting organs from lethal doses of lipopolysaccharide (LPS). Six groups of rabbits (N = 6) were used in this study. Two groups acted as controls and received only saline and no LPS injections. For the test groups, 1 mL honey (500 mg/kg in saline) was intravenously injected into two groups (treated), while saline (1 mL) was injected into the other two groups (untreated); after 1 h, all four test groups were intravenously-injected with LPS (0.5 mg/kg). Eight hours after the LPS injection, blood and organs were collected from three groups (one from each treatment stream) and blood parameters were measured and biochemical tests, histopathology, and myeloperoxidase assessment were performed. For survival rate tests, rabbits from the remaining three groups were monitored over a 2-week period. Treatment with honey showed protective effects on organs through the improvement of organ blood parameters, reduced infiltration of neutrophils, and decreased myeloperoxidase activity. Honey-treated rabbits also showed reduced mortality after LPS injection compared with untreated rabbits. Honey may have a therapeutic effect in protecting organs during inflammatory diseases. PMID:22754370

Kassim, Mustafa; Mansor, Marzida; Al-Abd, Nazeh; Yusoff, Kamaruddin Mohd

2012-01-01

230

Spirulina Promotes Stem Cell Genesis and Protects against LPS Induced Declines in Neural Stem Cell Proliferation  

Microsoft Academic Search

Adult stem cells are present in many tissues including, skin, muscle, adipose, bone marrow, and in the brain. Neuroinflammation has been shown to be a potent negative regulator of stem cell and progenitor cell proliferation in the neurogenic regions of the brain. Recently we demonstrated that decreasing a key neuroinflammatory cytokine IL-1? in the hippocampus of aged rats reversed the

Adam D. Bachstetter; Jennifer Jernberg; Andrea Schlunk; Jennifer L. Vila; Charles Hudson; Michael J. Cole; R. Douglas Shytle; Jun Tan; Paul R. Sanberg; Cyndy D. Sanberg; Cesario Borlongan; Yuji Kaneko; Naoki Tajiri; Carmelina Gemma; Paula C. Bickford; Tsuneya Ikezu

2010-01-01

231

Inhibition of LPS-induced splenocyte proliferation by ortho-substituted polychlorinated biphenyl congeners  

Microsoft Academic Search

Polychlorinated biphenyls (PCBs) are persistent environmental contaminants, and their ubiquitous nature has prompted studies of their potential health hazards. As a result of their lipophilic nature, PCBs accumulate in breast milk and subsequently affect the health of offspring of exposed individuals. Biological effects of PCBs in animals have mostly been attributed to coplanar congeners, although effects of ortho congeners also

L. Ashley Smithwick; Andrew Smith; John F. Quensen; Allison Stack; Lucille London; Pamela J. Morris

2003-01-01

232

LPS-Induced Genes in Intestinal Tissue of the Sea Cucumber Holothuria glaberrima  

PubMed Central

Metazoan immunity is mainly associated with specialized cells that are directly involved with the immune response. Nevertheless, both in vertebrates and invertebrates other organs might respond to immune activation and participate either directly or indirectly in the ongoing immune process. However, most of what is known about invertebrate immunity has been restricted to immune effector cells and little information is available on the immune responses of other tissues or organs. We now focus on the immune reactions of the intestinal tissue of an echinoderm. Our study employs a non-conventional model, the echinoderm Holothuria glaberrima, to identify intestinal molecules expressed after an immune challenge presented by an intra-coelomic injection of lipopolysaccharides (LPS). The expression profiles of intestinal genes expressed differentially between LPS-injected animals and control sea water-injected animals were determined using a custom-made Agilent microarray with 7209 sea cucumber intestinal ESTs. Fifty (50) unique sequences were found to be differentially expressed in the intestine of LPS-treated sea cucumbers. Seven (7) of these sequences represented homologues of known proteins, while the remaining (43) had no significant similarity with any protein, EST or RNA database. The known sequences corresponded to cytoskeletal proteins (Actin and alpha-actinin), metabolic enzymes (GAPDH, Ahcy and Gnmt), metal ion transport/metabolism (major yolk protein) and defense/recognition (fibrinogen-like protein). The expression pattern of 11 genes was validated using semi-quantitative RT-PCR. Nine of these corroborated the microarray results and the remaining two showed a similar trend but without statistical significance. Our results show some of the molecular events by which the holothurian intestine responds to an immune challenge and provide important information to the study of the evolution of the immune response. PMID:19584914

Ramirez-Gomez, Francisco; Ortiz-Pineda, Pablo A.; Rivera-Cardona, Gabriela; Garcia-Arraras, Jose E.

2009-01-01

233

Salidroside attenuates LPS-induced pro-inflammatory cytokine responses and improves survival in murine endotoxemia  

Microsoft Academic Search

Salidroside is a major component isolated from the Rhodiola rosea. In the present study, we investigated the anti-inflammatory effects of salidroside on cytokine production by lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages in vitro, and the results showed that salidroside reduced tumor necrosis factor-? (TNF-?), interleukin-6 (IL-6) and interleukin-1? (IL-1?) secretions. This inspired us to further study the effects of salidroside in

Shuang Guan; Haihua Feng; Bocui Song; Weixiao Guo; Ying Xiong; Guoren Huang; Weiting Zhong; Meixia Huo; Na Chen; Jing Lu; Xuming Deng

234

Role of inducible nitric oxide synthase expression and peroxynitrite formation in guinea pig ileitis  

Microsoft Academic Search

Background & Aims Inflammatory bowel disease is characterized by increased synthesis of nitric oxide. The aim of this study was to determine if inducible NO synthase (iNOS) was responsible for tissue injury, potentially via peroxynitrite formation, in the guinea pig model of gut inflammation. Methods Inflammation was induced in guinea pig ileum by intraluminal administration of the hapten trinitrobenzene sulfonic

Mark J. S. Miller; Jane H. Thompson; Xiao-Jing Zhang; Halina Sadowska-Krowicka; Jane L. Kakkis; Upender K. Munshi; Manuel Sandoval; Janet L. Rossi; Sandra Eloby-Childress; Joseph S. Beckman; Yao Zu Ye; Charles P. Rodi; Pamela T. Manning; Mark G. Currie; David A. Clark

1995-01-01

235

Inhibition of endoplasmic reticulum stress alleviates lipopolysaccharide-induced lung inflammation through modulation of NF-?B/HIF-1? signaling pathway  

PubMed Central

Lipopolysaccharide (LPS) is involved in a variety of inflammatory disorders. Under stress conditions, endoplasmic reticulum (ER) loses the homeostasis in its functions, which is defined as ER stress. Little is known how ER stress is implicated in LPS-induced lung inflammation. In this study, effects of inhibition of ER stress on LPS-induced lung inflammation and transcriptional regulation were examined. An ER stress regulator, 4-phenylbutyrate (PBA) reduced LPS-induced increases of various ER stress markers in the lung. Furthermore, inhibition of ER stress reduced the LPS-induced lung inflammation. Moreover, LPS-induced increases of NF-?B and HIF-1? activity were lowered by inhibition of ER stress. These results suggest that inhibition of ER stress ameliorates LPS-induced lung inflammation through modulation of NF-?B/I?B and HIF-1? signaling pathway. PMID:23359618

Kim, Hee Jung; Jeong, Jae Seok; Kim, So Ri; Park, Seung Yong; Chae, Han Jung; Lee, Yong Chul

2013-01-01

236

Purification and characterization of a nitric oxide inhibitory peptide from Ruditapes philippinarum.  

PubMed

Ruditapes philippinarum (R. philippinarum) were hydrolyzed using 8 proteases to produce an anti-inflammatory peptide of the various hydrolysates produced, the Alcalase hydrolysate exhibited the highest nitric oxide (NO) inhibitory activity. The derived peptide was purified using high performance liquid chromatography (HPLC) and NO-inhibitory activity of the purified compound was evaluated. The sequence of the NO-inhibitory peptide obtained was composed of 10 amino acid residues, Gln-Cys-Gln-Gln-Ala-Val-Gln-Ser-Ala-Val at N-terminal position. In addition, we investigated the inhibitory effect of the purified peptide from R. philippinarum on NO production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. In this analysis the purified peptide from R. philippinarum was shown to inhibit LPS-induced NO production in RAW264.7 cells. The present results indicate that the purified peptide displayed potent anti-inflammation activity in RAW264.7 cells. PMID:22386812

Lee, Seung-Jae; Kim, Eun-Kyung; Kim, Yon-Suk; Hwang, Jin-Woo; Lee, Kwang Ho; Choi, Dong-Kug; Kang, Hyun; Moon, Sang-Ho; Jeon, Byong-Tae; Park, Pyo-Jam

2012-05-01

237

Effects of Ginkgo biloba extract (EGb 761) and quercetin on lipopolysaccharide-induced release of nitric oxide  

Microsoft Academic Search

Administration of bacterial lipopolysaccharide (LPS) to laboratory animals and cultured macrophages is known to induce the production of nitric oxide (NO) from inducible nitric oxide synthase (iNOS). Here we show that pre-treatment with Ginkgo biloba extract (EGb 761) suppresses the in vivo production of NO (measured by the Griess reaction) after challenge with LPS. In order to begin to understand

Teri L Wadsworth; Dennis R Koop

2001-01-01

238

The chloroform fraction of Solanum nigrum suppresses nitric oxide and tumor necrosis factor-? in LPS-stimulated mouse peritoneal macrophages through inhibition of p38, JNK and ERK1/2.  

PubMed

Solanum nigrum L., commonly known as black nightshade, is used worldwide for the treatment of skin and mucosal ulcers, liver cirrhosis and edema. We aimed to determine the anti-inflammatory active fraction of S. nigrum by serial extractions. S. nigrum was first extracted with methanol, then fractionated with chloroform and water. The effects of S. nigrum fractions, diosgenin and ?-solanine on LPS/interferon-gamma-induced nitric oxide (NO) and inducible NO synthase (iNOS), or LPS-induced tumor necrosis factor-? (TNF-?) and interleukin (IL)-6, in mouse peritoneal macrophages were determined. Western blotting analysis was used to detect LPS-induced phosphorylation of p38, JNK and ERK1/2. The chloroform fraction of S. nigrum was cytotoxic in a time and concentration dependent manner; however, the methanol and water fractions were not. The chloroform fraction reduced NO through inhibition of iNOS synthesis and inhibited TNF-? and IL-6 at the level of protein secretion; the methanol and water fractions showed a weak or no effect. The chloroform fraction also suppressed p38, JNK and ERK1/2. Diosgenin and ?-solanine were cytotoxic at a high concentration. In particular, diosgenin was able to inhibit TNF-? and IL-6, but both compounds did not affect LPS-induced iNOS expression. These results indicate that the anti-inflammatory compounds of S. nigrum exist preferentially in the nonpolar fraction, ruling out the possibility that diosgenin and ?-solanine are the likely candidates. The inhibition of iNOS, TNF-? and IL-6 by the chloroform fraction may be partly due to the suppression of p38, JNK and ERK1/2. Further study is required to identify the active compounds of S. nigrum. PMID:22083995

Kang, Hee; Jeong, Ha-Deok; Choi, Ho-Young

2011-01-01

239

Korean Red Ginseng saponin fraction modulates radiation effects on lipopolysaccharide-stimulated nitric oxide production in RAW264.7 macrophage cells  

PubMed Central

Background In previous work, we reported that Korean Red Ginseng saponin fraction (RGSF) showed anti-inflammatory activities in vitro and in vivo. Methods The present study investigated the radioprotective properties of RGSF by examining its effects on ionizing radiation (IR)-enhanced and lipopolysaccharide (LPS)-mediated inflammatory responses in murine macrophage cells. Results RGSF induced strong downregulation of IR-enhanced and LPS-induced proinflammatory responses such as nitric oxide (NO) production (Inhibitory Concentration 50 (IC50) = 5.1 ± 0.8 ?M) and interleukin-1? levels. RGSF was found to exert its radioprotective effects by inhibition of a signaling cascade that activated checkpoint kinase 2–nuclear factor-?B. In addition, RGSF strongly inhibited IR-enhanced LPS-induced expression of hemoxyganase-1, implying that the latter may be a potential target of RGSF. Conclusion Taken together, our data suggest that RGSF can be considered and developed for use as an effective radioprotective agent with minimal adverse effects. PMID:25378996

Lee, Young Ji; Han, Jeong Yoon; Lee, Chang Geun; Heo, Kyu; Park, Se Il; Park, Yoo Soo; Kim, Joong Sun; Yang, Kwang Mo; Lee, Ki-Ja; Kim, Tae-Hwan; Rhee, Man Hee; Kim, Sung Dae

2014-01-01

240

Astrocyte-induced cortical vasodilation is mediated by D-serine and endothelial nitric oxide synthase  

E-print Network

Astrocyte-induced cortical vasodilation is mediated by D-serine and endothelial nitric oxide and release NMDA receptor coagonist, D-serine, in response to neurotransmitter input. Mouse cortical slice of penetrating arterioles in a man- ner attenuated by scavenging D-serine with D-amino acid oxidase, deleting

Newman, Eric A.

241

Inducible nitric oxide synthase inhibitor of the Chinese herb I. Saposhnikovia divaricata (Turcz.) Schischk  

Microsoft Academic Search

l-Arginine derived nitric oxide (NO) and its derivatives, such as nitrogen dioxide and peroxynitrite, play a role in inflammation and also possibly in the multistage process of carcinogenesis. Four furanocoumarins and eight chromones isolated from the dried root of Saposhnikovia divaricata (Fang Feng in Chinese) and evaluated for their effects on the synthesis of NO induced by lipopolysaccharide (LPS) in

Ching-Chiung Wang; Lih-Geeng Chen; Ling-Ling Yang

1999-01-01

242

The Mosquito Anopheles stephensi Limits Malaria Parasite Development with Inducible Synthesis of Nitric Oxide  

Microsoft Academic Search

We have discovered that the mosquito Anopheles stephensi, a natural vector of human malaria, limits parasite development with inducible synthesis of nitric oxide (NO). Elevated expression of A. stephensi NO synthase (NOS), which is highly homologous to characterized NOS genes, was detected in the midgut and carcass soon after invasion of the midgut by Plasmodium. Early induction is likely primed

Shirley Luckhart; Yoram Vodovotz; Liwang Cui; Ronald Rosenberg

1998-01-01

243

A narcotic dose of carbon monoxide induces neuronal haeme oxygenase and nitric oxide synthetase in sheep  

Microsoft Academic Search

Twelve Romney ewes were exposed to either 1% carbon monoxide (CO) in air (n=6) or room air alone for 120 min and were killed 15 days later for histological and immunohistochemical examination. This dose of CO was narcotic and induced both haeme oxygenase and nitric oxide synthetase in brain neurons, but not in endothelial cells. The mechanism of the induction

Des Gorman; Y. L Huang; Chris Williams

2002-01-01

244

Role of Inducible Nitric Oxide Synthase in Resistance to Mycobacterium leprae in Mice  

Microsoft Academic Search

The manifestation of leprosy in humans is largely determined by host immunity to Mycobacterium leprae and is a model for immunoregulation in a human disease. However, animal models available for explora- tion of the leprosy spectrum are inadequate. This study explored M. leprae infection in mice deficient in inducible nitric oxide synthase, and this report describes elements resembling borderline tuberculoid

LINDA B. ADAMS; CHARLES K. JOB; JAMES L. KRAHENBUHL

2000-01-01

245

Isolation of benzoic and cinnamic acid derivatives from the grains of Sorghum bicolor and their inhibition of lipopolysaccharide-induced nitric oxide production in RAW 264.7 cells.  

PubMed

Two new caffeoylglycerols, (hwanggeumchal A-B, 9-10), together with eight known derivatives (1-8) were isolated from the grains of Sorghum bicolor (L.) Moench var. hwanggeumchal. Their chemical structures were established mainly by 1D and 2D NMR techniques and MS data analysis. Amongst those, methyl 3,4-dihydroxybenzoate (2), 3,4,5-trihydroxycinnamate (3), methyl 3,4-dihydroxycinnamate (5), caffeoylglycolic acid methyl ester (7) and 1-O-caffeoylglycerol (8) displayed potential inhibitory effects against LPS-induced NO production in macrophage RAW264.7 cells with IC50 values of 11.9, 2.9, 27.1, 29.0 and 18.5?M, respectively. Furthermore, these compounds dose-dependently reduced the LPS-induced iNOS expression. In addition, pre-incubation of cells with compounds 2, 3 and 5 significantly suppressed LPS-induced COX-2 protein expression. SAR investigation revealed that compounds with a methyl ester (COOCH3) group possessed stronger activity. Our obtained data suggest that S. bicolor and its caffeoylglyceride-enrich extracts may be applied as supplemental and/or functional foods having a beneficial effect against inflammation. PMID:25172742

Nguyen, Phi-Hung; Zhao, Bing Tian; Lee, Jeong Hyung; Kim, Young Ho; Min, Byung Sun; Woo, Mi Hee

2015-02-01

246

Protective role of nitric oxide during hydrogen peroxide-induced oxidative stress in tobacco plants  

Microsoft Academic Search

Nitric oxide, produced from exogenous NO donor, sodium nitroprusside, and hydrogen peroxide exerted antagonistic effects on\\u000a tobacco leaves at micromolar concentrations but induced synergistic effects at millimolar concentrations. During H2O2-induced oxidative stress, low concentrations of NO inhibited lipid peroxidation, counteracted the fragmentation of total\\u000a DNA, and prevented accumulation of soluble proteins in Nicotiana plumbaginifolia cells. When applied at high concentrations,

L. V. Dubovskaya; E. V. Kolesneva; D. M. Knyazev; I. D. Volotovskii

2007-01-01

247

Involvement of inducible nitric oxide synthase in radiation-induced vascular endothelial damage.  

PubMed

The use of radiation therapy has been linked to an increased risk of cardiovascular disease. To understand the mechanisms underlying radiation-induced vascular dysfunction, we employed two models. First, we examined the effect of X-ray irradiation on vasodilation in rabbit carotid arteries. Carotid arterial rings were irradiated with 8 or 16 Gy using in vivo and ex vivo methods. We measured the effect of acetylcholine-induced relaxation after phenylephrine-induced contraction on the rings. In irradiated carotid arteries, vasodilation was significantly attenuated by both irradiation methods. The relaxation response was completely blocked by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, a potent inhibitor of soluble guanylate cyclase. Residual relaxation persisted after treatment with L-N(?)-nitroarginine (L-NA), a non-specific inhibitor of nitric oxide synthase (NOS), but disappeared following the addition of aminoguanidine (AG), a selective inhibitor of inducible NOS (iNOS). The relaxation response was also affected by tetraethylammonium, an inhibitor of endothelium-derived hyperpolarizing factor activity. In the second model, we investigated the biochemical events of nitrosative stress in human umbilical-vein endothelial cells (HUVECs). We measured iNOS and nitrotyrosine expression in HUVECs exposed to a dose of 4 Gy. The expression of iNOS and nitrotyrosine was greater in irradiated HUVECs than in untreated controls. Pretreatment with AG, L-N(6)-(1-iminoethyl) lysine hydrochloride (a selective inhibitor of iNOS), and L-NA attenuated nitrosative stress. While a selective target of radiation-induced vascular endothelial damage was not definitely determined, these results suggest that NO generated from iNOS could contribute to vasorelaxation. These studies highlight a potential role of iNOS inhibitors in ameliorating radiation-induced vascular endothelial damage. PMID:23704776

Hong, Chang-Won; Kim, Young-Mee; Pyo, Hongryull; Lee, Joon-Ho; Kim, Suwan; Lee, Sunyoung; Noh, Jae Myoung

2013-11-01

248

Nitric oxide mediates cytokine-induced inhibition of insulin secretion by human islets of Langerhans.  

PubMed Central

Cytokines have been implicated as immunological effector molecules that mediate beta cell destruction associated with insulin-dependent diabetes mellitus. In this report we demonstrate that the cytokine combination of human recombinant interleukin 1 beta (IL-1 beta), tumor necrosis factor alpha (TNF-alpha), and interferon gamma (IFN-gamma) induces the formation of nitric oxide by human islets. This combination of cytokines stimulates both the formation of the nitric oxide derivative, nitrite, and the accumulation of cGMP by human islets. The nitric oxide synthase inhibitor NG-monomethyl-L-arginine prevents formation of both cGMP and nitrite. IL-1 beta and IFN-gamma are sufficient to induce nitric oxide formation by human islets, whereas TNF-alpha potentiates nitrite production. This combination of cytokines (IL-1 beta, TNF-alpha, and IFN-gamma) also influences insulin secretion by human islets. Pretreatment of human islets with low concentrations of this cytokine combination (IL-1 beta at 15 units/ml, 0.7 nM TNF-alpha, and IFN-gamma at 150 units/ml) appears to slightly stimulate insulin secretion. Higher concentrations (IL-1 beta at 75 units/ml, 3.5 nM TNF-alpha, and IFN-gamma at 750 units/ml) inhibit insulin secretion from human islets, and the inhibitory effect is prevented by NG-monomethyl-L-arginine. This higher concentration of cytokines also induces the formation of an electron paramagnetic resonance-detectable g = 2.04 axial feature by human islets that is characteristic of the formation of an iron-dithio-dinitrosyl complex. The formation of this complex is prevented by NG-monomethyl-L-arginine, thus confirming that this cytokine combination induces the formation of nitric oxide by human islets. These results indicate that nitric oxide mediates the inhibitory effects of cytokines on glucose-stimulated insulin secretion by human islets and suggest that nitric oxide may participate in beta-cell dysfunction associated with insulin-dependent diabetes mellitus. PMID:8383325

Corbett, J A; Sweetland, M A; Wang, J L; Lancaster, J R; McDaniel, M L

1993-01-01

249

Castration Induces Parkinson Disease Pathologies in Young Male Mice via Inducible Nitric-oxide Synthase*  

PubMed Central

Although Parkinson disease (PD) is a progressive neurodegenerative disorder, available animal models do not exhibit irreversible neurodegeneration, and this is a major obstacle in finding out an effective drug against this disease. Here we delineate a new irreversible model to study PD pathogenesis. The model is based on simple castration of young male mice. Levels of inducible nitric-oxide synthase (iNOS), glial markers (glial fibrillary acidic protein and CD11b), and ?-synuclein were higher in nigra of castrated male mice than normal male mice. On the other hand, after castration, the level of glial-derived neurotrophic factor (GDNF) markedly decreased in the nigra of male mice. Accordingly, castration also induced the loss of tyrosine hydroxylase-positive neurons in the nigra and decrease in tyrosine hydroxylase-positive fibers and neurotransmitters in the striatum. Reversal of nigrostriatal pathologies in castrated male mice by subcutaneous implantation of 5?-dihydrotestosterone pellets validates an important role of male sex hormone in castration-induced nigrostriatal pathology. Interestingly, castration was unable to cause glial activation, decrease nigral GDNF, augment the death of nigral dopaminergic neurons, induce the loss of striatal fibers, and impair neurotransmitters in iNOS?/? male mice. Furthermore, we demonstrate that iNOS-derived NO is responsible for decreased expression of GDNF in activated astrocytes. Together, our results suggest that castration induces nigrostriatal pathologies via iNOS-mediated decrease in GDNF. These results are important because castrated young male mice may be used as a simple, toxin-free, and nontransgenic animal model to study PD-related nigrostriatal pathologies, paving the way for easy drug screening against PD. PMID:23744073

Khasnavis, Saurabh; Ghosh, Anamitra; Roy, Avik; Pahan, Kalipada

2013-01-01

250

Folic acid supplementation during pregnancy protects against lipopolysaccharide-induced neural tube defects in mice.  

PubMed

Folic acid is a water-soluble B-complex vitamin. Increasing evidence demonstrates that physiological supply of folic acid during pregnancy prevents folic acid deficiency-related neural tube defects (NTDs). Previous studies showed that maternal lipopolysaccharide (LPS) exposure caused NTDs in rodents. The aim of this study was to investigate the effects of high-dose folic acid supplementation during pregnancy on LPS-induced NTDs. Pregnant mice were intraperitoneally injected with LPS (20 ?g/kg/d) from gestational day (GD) 8 to GD12. As expected, a five-day LPS injection resulted in 19.96% of fetuses with NTDs. Interestingly, supplementation with folic acid (3mg/kg/d) during pregnancy significantly alleviated LPS-induced NTDs. Additionally, folic acid significantly attenuated LPS-induced fetal growth restriction and skeletal malformations. Additional experiment showed that folic acid attenuated LPS-induced glutathione (GSH) depletion in maternal liver and placentas. Moreover, folic acid significantly attenuated LPS-induced expression of placental MyD88. Additionally, folic acid inhibited LPS-induced c-Jun NH2-terminal kinase (JNK) phosphorylation and nuclear factor kappa B (NF-?B) activation in placentas. Correspondingly, folic acid significantly attenuated LPS-induced tumor necrosis factor (TNF)-?, interleukin (IL)-1? and IL-6 in placentas, maternal serum and amniotic fluid. In conclusion, supplementation with high-dose folic acid during pregnancy protects against LPS-induced NTDs through its anti-inflammatory and anti-oxidative effects. PMID:24177262

Zhao, Mei; Chen, Yuan-Hua; Chen, Xue; Dong, Xu-Ting; Zhou, Jun; Wang, Hua; Wu, Shu-Xian; Zhang, Cheng; Xu, De-Xiang

2014-01-13

251

Inhibitory effect of astragalin on expression of lipopolysaccharide-induced inflammatory mediators through NF-?B in macrophages.  

PubMed

Astragalin (kaempferol-3-O-glucoside), a newly found flavonoid from leaves of persimmon or Rosa agrestis, is known to have antiatopic dermatitis and antioxidant activity. However, the effect of astragalin on the inflammatory response is not well defined. Nitric oxide (NO) produced from the activated macrophages is well known as a mediator of inflammation. Transcription factor (NF)-?B mediates the inducible expression of a variety of genes involved in immune and inflammatory responses including inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and cytokines/chemokines. In the present study, we examined the inhibitory effects of astragalin on the lipopolysaccharide (LPS)-induced inflammatory mediators. Astragalin significantly reduced LPS-induced expression of iNOS, COX-2 and cytokines/chemokines, and production of NO in J774A.1 mouse macrophages. Astragalin inhibited LPSinduced activation of NF-?B as indicated by inhibition of degradation of I?B?, nuclear translocation of NF-?B, and NF-?B dependent gene reporter assay. The inhibitory effects of astragalin on the inflammatory mediators are comparable with quercetin, a well known flavonoid possessing antioxidant and anti-inflammatory activity. Using the mouse peritoneal macrophages, we confirmed the inhibitory effect of astragalin on NO production and NF-?B activation. Taken together, our results indicate that astragalin inhibits expression of proinflammatory mediators through the inhibition of NF-?B in macrophages. PMID:22210036

Kim, Mi-Sun; Kim, Sang-Hyun

2011-12-01

252

Regulatory Effect of 25-hydroxyvitamin D3 on Nitric Oxide Production in Activated Microglia  

PubMed Central

Microglia are activated by inflammatory and pathophysiological stimuli in neurodegenerative diseases, and activated microglia induce neuronal damage by releasing cytotoxic factors like nitric oxide (NO). Activated microglia synthesize a significant amount of vitamin D3 in the rat brain, and vitamin D3 has an inhibitory effect on activated microglia. To investigate the possible role of vitamin D3 as a negative regulator of activated microglia, we examined the effect of 25-hydroxyvitamin D3 on NO production of lipopolysaccharide (LPS)-stimulated microglia. Treatment with LPS increased the production of NO in primary cultured and BV2 microglial cells. Treatment with 25-hydroxyvitamin D3 inhibited the generation of NO in LPS-activated primary microglia and BV2 cells. In addition to NO production, expression of 1-?-hydroxylase and the vitamin D receptor (VDR) was also upregulated in LPS-stimulated primary and BV2 microglia. When BV2 cells were transfected with 1-?-hydroxylase siRNA or VDR siRNA, the inhibitory effect of 25-hydroxyvitamin D3 on activated BV2 cells was suppressed. 25-Hydroxyvitamin D3 also inhibited the increased phosphorylation of p38 seen in LPS-activated BV2 cells, and this inhibition was blocked by VDR siRNA. The present study shows that 25-hydroxyvitamin D3 inhibits NO production in LPS-activated microglia through the mediation of LPS-induced 1-?-hydroxylase. This study also shows that the inhibitory effect of 25-hydroxyvitamin D3 on NO production might be exerted by inhibiting LPS-induced phosphorylation of p38 through the mediation of VDR signaling. These results suggest that vitamin D3 might have an important role in the negative regulation of microglial activation. PMID:25352759

Hur, Jinyoung; Lee, Pyeongjae; Kim, Mi Jung

2014-01-01

253

The nitric oxide donor, V-PYRRO\\/NO, protects against acetaminophen-induced hepatotoxicity in mice  

Microsoft Academic Search

The liver-selective nitric oxide (NO) donor, O2-vinyl 1-(pyrrolidin-1-yl)diazen-1-ium-1,2-diolate (V-PYRRO\\/NO), is metabolized by P-450 enzymes to release NO in the liver, and is shown to protect the liver from tumor necrosis factor ? (TNF-?)-induced apoptosis and D-glactosamine\\/endotoxin–induced hepatotoxicity. This study was undertaken to examine the effects of V-PYRRO\\/NO on acetaminophen-induced hepatotoxicity in mice. Mice were given V-PYRRO\\/NO via osmotic pumps (1.8-5.4

Jie Liu; Chengxiu Li; Michael P. Waalkes; James Clark; Page Myers; Joseph E. Saavedra; Larry K. Keefer

2003-01-01

254

The role of nitric oxide in testosterone-induced vasodilation in pig coronary arteries and rat thoracic aorta  

E-print Network

Several studies have provided evidence that the administration of testosterone to vascular tissue causes vasodilation (Costarella, Yue). This study examines the role of nitric oxide (NO) as a potential mechanism of testosterone-induced vasodilation...

Piefer, Jason William

2013-02-22

255

Inhibition of Viral Replication by Interferon-gamma-Induced Nitric Oxide Synthase  

Microsoft Academic Search

Interferons (IFNs) induce antiviral activity in many cell types. The ability of IFN-gamma to inhibit replication of ectromelia, vaccinia, and herpes simplex-1 viruses in mouse macrophages correlated with the cells' production of nitric oxide (NO). Viral replication was restored in IFN-gamma-treated macrophages exposed to inhibitors of NO synthase. Conversely, epithelial cells with no detectable NO synthesis restricted viral replication when

Gunasegaran Karupiah; Qiao-Wen Xie; R. Mark L. Buller; Carl Nathan; Cornelio Duarte; John D. Macmicking

1993-01-01

256

Photochemically-Induced Valency Adjustment of Plutonium and Neptunium in Nitric Acid Solution Using Mercury Lamp  

Microsoft Academic Search

A photochemically-induced valency adjustment method has been studied to remove Np from the mixed nitric acid solutions of Pu and Np in connection with the Purex reprocessing. The valencies of Pu and Np ions were adjusted to be Pu(HI) and Np(V) under the initial conditions and their concentrations were 1x10 and 1x10 mol·dm, respectively. The experiments were carried out under

Yukio WADA; Kouji WADA; Takayuki GOIBUCHI; Hiroshi TOMIYASU

1994-01-01

257

Visualizing inducible nitric-oxide synthase in living cells with a heme-binding fluorescent inhibitor  

Microsoft Academic Search

The study of nitric-oxide synthase (NOS) physiology is constrained by the lack of suitable probes to detect NOS in living cells or animals. Here, we characterized a fluorescent inducible NOS (iNOS) inhibitor called PIF (pyrimidine imidazole FITC) and examined its utility for microscopic imaging of iNOS in living cells. PIF binding to iNOS displayed high affinity, isoform selectivity, and heme

Koustubh Panda; Mamta Chawla-Sarkar; Cecile Santos; Thomas Koeck; Serpil C. Erzurum; John F. Parkinson; Dennis J. Stuehr

2005-01-01

258

Altered responses to bacterial infection and endotoxic shock in mice lacking inducible nitric oxide synthase  

Microsoft Academic Search

Mice deficient in inducible nitric oxide synthase (iNOS) were generated to test the idea that !NOS defends the host against infectious agents and tumor cells at the risk of contributing to tissue damage and shock. iNOS-I- mice failed to restrain the replication of Listeria monocytogenes in vivo or lymphoma cells in vitro. Bacterial endotoxic lipopolysaccharide (LPS) caused shock and death

John D. MacMicking; Carl Nathan; Gary Hom; Nicole Chartrain; Daniel S. Fletcher; Myrna Trumbauer; Karla Stevens; Qiao-wen Xie; Karen Sokol; Nancy Hutchinson; Howard Chen; John S. Mudget

1995-01-01

259

Role of nitric oxide-induced mtDNA damage in mitochondrial dysfunction and apoptosis  

Microsoft Academic Search

An increasing body of evidence suggests that nitric oxide (NO) can be cytotoxic and induce apoptosis. NO can also be genotoxic and cause DNA damage and mutations. It has been shown that NO damages mitochondrial DNA (mtDNA) to a greater extent than nuclear DNA. Previously, we reported that conditional targeting of the DNA repair protein hOGG1 into mitochondria using a

Lyudmila I. Rachek; Valentina I. Grishko; Susan P. LeDoux; Glenn L. Wilson

2006-01-01

260

Salicylic Acid-induced Nitric Oxide and ROS Generation Stimulate Ginsenoside Accumulation in Panax ginseng Roots  

Microsoft Academic Search

We evaluated the involvement of nitric oxide (NO) in salicylic acid (SA)-induced accumulation of ginsenoside in adventitious\\u000a roots of Panax ginseng and its mediation by reactive oxygen species (ROS). Related effects of SA on components of the antioxidant system were also\\u000a sought. Adventitious roots of P. ginseng were grown in suspension culture for 3 weeks in MS medium and treated over

Rajesh Kumar Tewari; Kee-Yoeup Paek

261

Nitric oxide modulates pancreatic edema formation in rat caerulein-induced pancreatitis  

Microsoft Academic Search

This study was designed to investigate the role of nitric oxide (NO) in the formation of pancreatic edema in caerulein-induced\\u000a pancreatitis in rats. Pancreatitis was produced by two intraperitoneal injections of caerulein, and plasma amylase concentration,\\u000a pancreatic edema index (pancreatic wet weight\\/body weight), and Evans blue extravasation (as a measure of vascular permeability)\\u000a were evaluated 5h after the first injection.

Takashi Abe; Tooru Shimosegawa; Akihiko Satoh; Reishi Abe; Yoshifumi Kikuchi; Masaru Koizumi; Takayoshi Toyota

1995-01-01

262

Suppression of Bleomycin-Induced Nitric Oxide Production in Mice by Taurine and Niacin  

Microsoft Academic Search

The effects of taurine (T) and niacin (N) on the influx of inflammatory cells and nitric oxide (NO) levels in bronchoalveolar lavage fluid (BALF) and expression of inducible NO synthase (iNOS) mRNA and iNOS protein in lungs were evaluated in the bleomycin (BL)–mouse model of lung fibrosis. Mice were placed into four groups: saline-instilled (SA) with a control diet (CD)

G. Gurujeyalakshmi; Yingjin Wang; Shri N. Giri

2000-01-01

263

Cytokine-induced nitric oxide production inhibits mitochondrial energy production and impairs contractile function in rat cardiac myocytes  

Microsoft Academic Search

OBJECTIVESThe present study examined whether nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) can directly inhibit aerobic energy metabolism and impair cell function in interleukin (IL)-1?–stimulated cardiac myocytes.BACKGROUNDRecent reports have indicated that excessive production of NO induced by cytokines can disrupt cellular energy balance through the inhibition of mitochondrial respiration in a variety of cells. However, it is

Tetsuya Tatsumi; Satoaki Matoba; Akira Kawahara; Natsuya Keira; Jun Shiraishi; Kazuko Akashi; Miyuki Kobara; Tetsuya Tanaka; Maki Katamura; Chiaki Nakagawa; Bon Ohta; Takeshi Shirayama; Kazuo Takeda; Jun Asayama; Henry Fliss; Masao Nakagawa

2000-01-01

264

Vaccinium myrtillus ameliorates unpredictable chronic mild stress induced depression: possible involvement of nitric oxide pathway.  

PubMed

Chronic unpredictable stressors can produce a situation similar to clinical depression and such animal models can be used for the preclinical evaluation of antidepressants. Nitric oxide, a secondary messenger molecule, has been implicated in neurotransmission, synaptic plasticity, learning, aggression and depression. Vaccinium myrtillus (bilberry) extract is a potent inhibitor of reactive oxygen/nitrogen species and cytokine production. The present study investigated the role of nitric oxide in the antidepressant action of Vaccinium myrtillus in unpredictable chronic mild stress-induced depression in mice. Animals were subjected to different stress paradigms daily for a period of 21 days to induce depressive-like behavior. Pretreatment with L-arginine significantly reversed the protective effect of bilberry (500 mg/kg) on chronic stress-induced behavioral (immobility period, sucrose preference) and biochemical (lipid peroxidation and nitrite levels; endogenous antioxidant activities) in stressed mice. Furthermore, L-NAME (10 mg/kg) pretreatment with a sub-effective dose of bilberry (250 mg/kg) significantly potentiated the protective effect of bilberry extract. The study revealed that modulation of the nitric oxide pathway might be involved in antidepressant-like effects of Vaccinium myrtillus in stressed mice. PMID:22488796

Kumar, Baldeep; Arora, Vipin; Kuhad, Anurag; Chopra, Kanwaljit

2012-04-01

265

Auxin-induced nitric oxide, cGMP and gibberellins were involved in the gravitropism  

NASA Astrophysics Data System (ADS)

Gravitropism is the asymmetric growth or curvature of plant organs in response to gravistimulation. There is a complex signal transduction cascade which involved in the differential growth of plants in response to changes in the gravity vector. The role of auxin in gravitropism has been demonstrated by many experiments, but little is known regarding the molecular details of such effects. In our studies before, mediation of the gravitropic bending of soybean roots and rice leaf sheath bases by nitric oxide, cGMP and gibberellins, are induced by auxin. The asymmetrical distribution of nitric oxide, cGMP and gibberellins resulted from the asymmetrical synthesis of them in bending sites. In soybean roots, inhibitions of NO and cGMP synthesis reduced differential NO and cGMP accumulation respectively, which both of these effects can lead to the reduction of gravitropic bending. Gibberellin-induced OsXET, OsEXPA4 and OsRWC3 were also found involved in the gravitropic bending. These data indicated that auxin-induced nitric oxide, cGMP and gibberellins were involved in the gravitropism. More experiments need to prove the more detailed mechanism of them.

Cai, Weiming; Hu, Liwei; Hu, Xiangyang; Cui, Dayong; Cai, Weiming

266

Methamphetamine-induced nitric oxide promotes vesicular transport in blood-brain barrier endothelial cells.  

PubMed

Methamphetamine's (METH) neurotoxicity is thought to be in part due to its ability to induce blood-brain barrier (BBB) dysfunction. Here, we investigated the effect of METH on barrier properties of cultured rat primary brain microvascular endothelial cells (BMVECs). Transendothelial flux doubled in response to METH, irrespective of the size of tracer used. At the same time, transendothelial electrical resistance was unchanged as was the ultrastructural appearance of inter-endothelial junctions and the distribution of key junction proteins, suggesting that METH promoted vesicular but not junctional transport. Indeed, METH significantly increased uptake of horseradish peroxidase into vesicular structures. METH also enhanced transendothelial migration of lymphocytes indicating that the endothelial barrier against both molecules and cells was compromised. Barrier breakdown was only observed in response to METH at low micromolar concentrations, with enhanced vesicular uptake peaking at 1 ?M METH. The BMVEC response to METH also involved rapid activation of endothelial nitric oxide synthase and its inhibition abrogated METH-induced permeability and lymphocyte migration, indicating that nitric oxide was a key mediator of BBB disruption in response to METH. This study underlines the key role of nitric oxide in BBB function and describes a novel mechanism of drug-induced fluid-phase transcytosis at the BBB. PMID:22960442

Martins, Tânia; Burgoyne, Thomas; Kenny, Bridget-Ann; Hudson, Natalie; Futter, Clare E; Ambrósio, António F; Silva, Ana P; Greenwood, John; Turowski, Patric

2013-02-01

267

Methamphetamine-induced nitric oxide promotes vesicular transport in blood-brain barrier endothelial cells  

PubMed Central

Methamphetamine's (METH) neurotoxicity is thought to be in part due to its ability to induce blood–brain barrier (BBB) dysfunction. Here, we investigated the effect of METH on barrier properties of cultured rat primary brain microvascular endothelial cells (BMVECs). Transendothelial flux doubled in response to METH, irrespective of the size of tracer used. At the same time, transendothelial electrical resistance was unchanged as was the ultrastructural appearance of inter-endothelial junctions and the distribution of key junction proteins, suggesting that METH promoted vesicular but not junctional transport. Indeed, METH significantly increased uptake of horseradish peroxidase into vesicular structures. METH also enhanced transendothelial migration of lymphocytes indicating that the endothelial barrier against both molecules and cells was compromised. Barrier breakdown was only observed in response to METH at low micromolar concentrations, with enhanced vesicular uptake peaking at 1 ?M METH. The BMVEC response to METH also involved rapid activation of endothelial nitric oxide synthase and its inhibition abrogated METH-induced permeability and lymphocyte migration, indicating that nitric oxide was a key mediator of BBB disruption in response to METH. This study underlines the key role of nitric oxide in BBB function and describes a novel mechanism of drug-induced fluid-phase transcytosis at the BBB. PMID:22960442

Martins, Tania; Burgoyne, Thomas; Kenny, Bridget-Ann; Hudson, Natalie; Futter, Clare E.; Ambrosio, Antonio F.; Silva, Ana P.; Greenwood, John; Turowski, Patric

2013-01-01

268

Inhibitory effects of N-(substituted benzoylamino)-4-ethyl-1,2,3,6-tetrahydropyridines on nitric oxide generation in stimulated raw 264.7 macrophages.  

PubMed

There has been great interest in reactive nitrogen intermediates and nitric oxide production in macrophages, particularly because of their contributory role in several pathophysiological conditions during acute and chronic inflammation. Several N-(substituted benzoylamino)-4-ethyl-1,2,3,6-tetrahydropyridines were previously synthesized as potential antiinflammatory agents. In the present study, the effects of four previously synthesized tetrahydropyridines (THPs) on cyclooxygenase (COX)-1 and COX-2 were screened and the effects of these compounds on lipopolysaccharide (LPS)-induced (2 micrograms/ml) nitric oxide and inducible nitric oxide synthase (iNOS) activity in RAW 264.7 macrophages were examined. 4-Bromo THP showed 9.4 microM of IC50 as the most potent derivative among the tested THPs followed by 4-nbuthyl, 4-fuoro, and 4-methyl THP with IC50 values of 30.9, 38.9 and 80.3 microM, respectively (indomethacin IC50 = 53.8 microM). None of the tested compounds showed cytotoxic effects to the RAW 264.7 macrophages. All of the tested THPs exhibited COX-1 and COX-2 nonselective inhibition. These results suggest that previously synthesized THP derivatives may have dual effects through inhibiting both COX and nitric oxide by inhibiting iNOS. PMID:12224381

Yoon, K; Soliman, K; Redda, K

2002-01-01

269

Various nitric oxide donors protect chick embryonic neurons from cyanide-induced apoptosis.  

PubMed

The discovery of numerous biochemical effects of cyanide not directly related to the inhibition of the respiratory chain, including the involvement of apoptosis, has challenged the basis of traditional antidote treatment, which primarily depends on nitrite-induced conversion of hemoglobin into methemoglobin, releasing the blockade of cytochrome c oxidase by high-affinity binding of cyanide as cyanmethemoglobin. The fact that amyl nitrite has antidotal effects not related to methemoglobin formation has unfolded new mechanism of actions of nitrites including release of nitric oxide (NO). In this study, we characterized the effect of various NO donor compounds on cyanide-induced cell death in cultured chick embryonic neurons. Apoptosis was induced by treating the neuronal cultures with 1 mM NaCN for 1 h, followed by a cyanide-free incubation period of 23 h. Using this treatment protocol, we showed that cyanide-induced apoptosis was blocked in the presence of the different NO donors sodium nitroprusside, S-nitrosoglutathione, S-nitroso-N-acetylpenicillamin, nitroglycerin, 3-morpholinosydnonimine, and diethylamine nitric oxide, indicating independence of the redox-related species of NO released. The effect was confirmed to be mediated by NO, since exhausted NO donors did not afford protection, and the mechanism likely involved chemical modification of thiol groups, since the effect was completely reversed by dithiothreitol. Furthermore, NMDA antagonists protected against cyanide-induced cell death, whereas inhibitors of nitric oxide synthase increased cyanide-induced apoptotic damage, indicating a protective effect of endogenously generated NO, at least in cell cultures. PMID:11053549

Jensen, M S; Nyborg, N C; Thomsen, E S

2000-11-01

270

The Endogenous Nitric Oxide Mediates Selenium-Induced Phytotoxicity by Promoting ROS Generation in Brassica rapa  

PubMed Central

Selenium (Se) is suggested as an emerging pollutant in agricultural environment because of the increasing anthropogenic release of Se, which in turn results in phytotoxicity. The most common consequence of Se-induced toxicity in plants is oxidative injury, but how Se induces reactive oxygen species (ROS) burst remains unclear. In this work, histofluorescent staining was applied to monitor the dynamics of ROS and nitric oxide (NO) in the root of Brassica rapa under Se(IV) stress. Se(IV)-induced faster accumulation of NO than ROS. Both NO and ROS accumulation were positively correlated with Se(IV)-induced inhibition of root growth. The NO accumulation was nitrate reductase (NR)- and nitric oxide synthase (NOS)-dependent while ROS accumulation was NADPH oxidase-dependent. The removal of NO by NR inhibitor, NOS inhibitor, and NO scavenger could alleviate Se(IV)-induced expression of Br_Rbohs coding for NADPH oxidase and the following ROS accumulation in roots, which further resulted in the amelioration of Se(IV)-induced oxidative injury and growth inhibition. Thus, we proposed that the endogenous NO played a toxic role in B. rapa under Se(IV) stress by triggering ROS burst. Such findings can be used to evaluate the toxic effects of Se contamination on crop plants. PMID:25333984

Hu, Liang-Bin; Li, You-Qin; Chen, Jian; Yang, Li-Fei

2014-01-01

271

Nitric Oxide Synergistically Enhances DNA Strand Breakage Induced by Polyhydroxyaromatic Compounds, but Inhibits That Induced by the Fenton Reaction  

Microsoft Academic Search

Reactive oxygen and nitrogen species play an important role in many human diseases including cancer. We have found that incubation of pBR322 plasmid DNA with a nitric oxide (NO)-releasing compound such as diethylamine NONOate and a polyhydroxyaromatic compound such as catechol, 1,4-hydroquinone, or pyrogallol caused synergistic induction of single-strand breakage, whereas either compound alone induced much less breakage. Phenol, resorcinol,

Yumiko Yoshie; Hiroshi Ohshima

1997-01-01

272

Two new natural products from the fruits of Alpinia oxyphylla with inhibitory effects on nitric oxide production in lipopolysaccharide-activated RAW264.7 macrophage cells.  

PubMed

Chemical investigation of the fruits of Alpinia oxyphylla led to an isolation of the two new natural products, 9-hydroxy epinootkatol (1) and (S)-2-pentanol-2-O-?-D-glucopyranoside (2), in addition to the nine known compounds, pinocembrin (3), tectochrysin (4), izalpinin (5), nookatone (6), yakuchinone A (7), protocatechuic acid (8), ?-sitosterol (9), daucosterol (10) and ?-sitosterol palmitate (11). Their structures were elucidated on the basis of physicochemical constants and NMR spectral data analysis. The effects of the isolated components on nitric oxide production in LPS-induced RAW 264.7 macrophages were examined. The two new natural compounds showed inhibitory activities with IC(50) values of 21.8 and 32.8 ?g/mL, respectively. PMID:23263808

Qing, Zhang Jun; Yong, Wang; Hui, Li Yong; Yong, Lai Wei; Long, Li Hai; Ao, Duan Jin; Xia, Pei Li

2012-12-01

273

Esculetin suppresses lipopolysaccharide-induced inflammatory mediators and cytokines by inhibiting nuclear factor-?B translocation in RAW 264.7 macrophages.  

PubMed

Although previous studies have demonstrated that the natural coumarin compound esculetin possesses various pharmacological properties, the molecular mechanism of esculetin-mediated anti-inflammatory potential is not fully understood. In this study, we determined the effects of esculetin on lipopolysaccharide (LPS)-induced inflammatory responses of murine RAW 264.7 macrophages. The results indicate that esculetin inhibits LPS-induced nitric oxide and prostaglandin E2 production in a concentration-dependent manner, and inhibits inducible nitric oxide synthase and cyclooxygenase-2 expression in RAW 264.7 cells. Esculetin also significantly suppresses the production of inflammatory cytokines, including tumor necrosis factor-? and interleukin-1?, which was concomitant with a decrease in their expression levels. Furthermore, it was observed that esculetin attenuated the LPS-mediated nuclear factor-kappa B (NF-?B) translocation associated with the blocking of inhibitor of NF-?B (I?B)-? degradation as well as reactive oxygen species (ROS) production, without any significant cytotoxicity. These data suggest that, by blocking NF-?B activation, esculetin suppresses LPS-elicited inflammatory events, and this is mediated, at least in part, by inhibiting the generation of ROS. Collectively, these findings provide mechanistic insights into the anti-inflammatory action of esculetin in macrophages. PMID:25310143

Hong, Su Hyun; Jeong, Hui-Kyung; Han, Min Ho; Park, Cheol; Choi, Yung Hyun

2014-12-01

274

Immunomodulatory Effect of Chinese Herbal Medicine Formula Sheng-Fei-Yu-Chuan-Tang in Lipopolysaccharide-Induced Acute Lung Injury Mice  

PubMed Central

Traditional Chinese medicine formula Sheng-Fei-Yu-Chuan-Tang (SFYCT), consisting of 13 medicinal plants, was used to treat patients with lung diseases. This study investigated the immunoregulatory effect of SFYCT on intratracheal lipopolysaccharides- (LPS-) challenged acute lung injury (ALI) mice. SFYCT attenuated pulmonary edema, macrophages, and neutrophils infiltration in the airways. SFYCT decreased inflammatory cytokines, including tumor necrosis factor-? (TNF?), interleukin-1?, and interleukin-6 and inhibited nitric oxide (NO) production but increased anti-inflammatory cytokines, interleukin-4, and interleukin-10, in the bronchoalveolar lavage fluid of LPS-challenged mice. TNF? and monocyte chemotactic protein-1 mRNA expression in the lung of LPS-challenged mice as well as LPS-stimulated lung epithelial cell and macrophage were decreased by SFYCT treatment. SFYCT treatment also decreased the inducible nitric oxide synthase expression and phosphorylation of nuclear factor-?B (NF-?B) in the lung of mice and macrophage with LPS stimulation. SFYCT treatment dose dependently decreased the LPS-induced NO and reactive oxygen species generation in LPS-stimulated macrophage. In conclusion, SFYCT attenuated lung inflammation during LPS-induced ALI through decreasing inflammatory cytokines production while increasing anti-inflammatory cytokines production. The immunoregulatory effect of SFYCT is related to inhibiting NF-?B phosphorylation. PMID:23997804

Lin, Chia-Hung; Yeh, Ching-Hua; Wang, Shulhn-Der; Wang, Jen-Shu; Kao, Shung-Te

2013-01-01

275

Temporal expression of hepatic inducible nitric oxide synthase in liver cirrhosis  

PubMed Central

AIM: Nitric oxide (NO) has been implicated in the pathogenesis of liver cirrhosis. We have found inducible nitric oxide synthase (iNOS) can be induced in hepatocytes of cirrhotic liver. This study further investigated the temporal expression and activity of hepatic iNOS in cirrhosis development. METHODS: Cirrhosis was induced in rats by chronic bile duct ligation (BDL). At different time points after the operation, samples were collected to examine NO concentration, liver function, and morphological changes. Hepatocytes were isolated for determination of iNOS mRNA, protein and enzymatic activity. RESULTS: Histological examination showed early cirrhosis 1-2 wk after BDL, with advanced cirrhosis at 3-4 wk. Bilirubin increased dramatically 3 d after BDL, but decreased by 47% on d 14. Three weeks after BDL, it elevated again. Systemic NO concentration did not increase significantly until 4 wk after BDL, when ascites developed. Hepatocyte iNOS mRNA expression was identified 3 d after BDL, and enhanced with time to 3 wk, but reduced thereafter. iNOS protein showed a similar pattern to mRNA expression. iNOS activity decreased from d 3 to d 7, but increased again thereafter till d 21. CONCLUSION: Hepatic iNOS can be induced in the early stage, which increases with time as cirrhosis develops. Its enzymatic activity is significantly correlated with protein expression and histological alterations of the liver, but not with systemic NO levels, nor with absolute values of liver function markers. PMID:15637745

Wei, Chang-Li; Hon, Wei-Min; Lee, Kang-Hoe; Khoo, Hoon-Eng

2005-01-01

276

Molecular cloning and expression of inducible nitric oxide synthase from human hepatocytes.  

PubMed Central

Nitric oxide is a short-lived biologic mediator for diverse cell types. Synthesis of an inducible nitric oxide synthase (NOS) in murine macrophages is stimulated by lipopolysaccharide (LPS) and interferon gamma. In human hepatocytes, NOS activity is induced by treatment with a combination of tumor necrosis factor, interleukin 1, interferon gamma, and LPS. We now report the molecular cloning and expression of an inducible human hepatocyte NOS (hep-NOS) cDNA. hep-NOS has 80% amino acid sequence homology to macrophage NOS (mac-NOS). Like other NOS isoforms, recognition sites for FMN, FAD, and NADPH are present, as well as a consensus calmodulin binding site. NOS activity in human 293 kidney cells transfected with hep-NOS cDNA is diminished by Ca2+ chelation and a calmodulin antagonist, reflecting a Ca2+ dependence not evident for mac-NOS. Northern blot analysis with hep-NOS cDNA reveals a 4.5-kb mRNA in both human hepatocytes and aortic smooth muscle cells following stimulation with LPS and cytokines. Human genomic Southern blots probed with human hep-NOS and human endothelial NOS cDNA clones display different genomic restriction enzyme fragments, suggesting distinct gene products for these NOS isoforms. hep-NOS appears to be an inducible form of NOS that is distinct from mac-NOS as well as brain and endothelial NOS isozymes. Images Fig. 2 Fig. 3 Fig. 4 PMID:7682706

Geller, D A; Lowenstein, C J; Shapiro, R A; Nussler, A K; Di Silvio, M; Wang, S C; Nakayama, D K; Simmons, R L; Snyder, S H; Billiar, T R

1993-01-01

277

Inhibitory effect of litchi (Litchi chinensis Sonn.) flower on lipopolysaccharide-induced expression of proinflammatory mediators in RAW264.7 cells through NF-?B, ERK, and JAK2/STAT3 inactivation.  

PubMed

Litchi (Litchi chinensis Sonn.) flower ethanolic extract (LFEE) was found to contain five flavanoids [total amount, 102.73 ± 5.50 mg/g of dried extract (gDE)], nine phenolic acids (total amount, 60.31 ± 4.52 mg/gDE), and proanthocyanidin A2 (79.31 ± 2.95 mg/gDE). LFEE was used to evaluate the inhibitory effects on lipopolysaccharide- (LPS-) induced pro-inflammatory mediators in RAW264.7 cells. The results showed that LFEE treatment could suppress the expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), the productions of nitric oxide (NO) and prostaglandin E2 (PGE2), and the secretions of pro-inflammatory cytokines [interleukin-1? (IL-1?), IL-6, and tumor necrosis factor ? (TNF-?)] in the LPS-mediated RAW264.7 cells. The attenuation of LPS-induced inflammatory responses by LFEE was found to be closely related to the inhibition of the translocation of nuclear factor ?B (NF-?B) p50/p65 subunits correlated with suppression of the activation of the inhibitor of ?B kinase (IKK) ?/? and downregulation of activation of extracellular signal-regulated kinase (ERK) and Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3). PMID:24641487

Yang, Deng-Jye; Chang, Yuan-Yen; Lin, Hui-Wen; Chen, Yi-Chen; Hsu, Shih-Han; Lin, Jau-Tien

2014-04-16

278

Structural significance of the benzoyl group at the C-3'-N position of paclitaxel for nitric oxide and tumor necrosis factor production by murine macrophages.  

PubMed

The antitumor agent paclitaxel (Taxol) mimics the actions of lipopolysaccharide (LPS) on murine macrophages (M phi). Recently, we have shown that the benzoyl group at the C-3' position of paclitaxel is the most important site to induce nitric oxide (NO) and tumor necrosis factor (TNF) production by C3H/HeN M phi (Biochem. Biophys. Res. Commun. 210, 678-686, 1996). In the present study, synthetic analogs of paclitaxel with replacement of the C-3'-N position were examined for their potencies to induce NO and TNF production by peritoneal M phi of LPS-responsive C3H/HeN mice and LPS-hyporesponsive C3H/HeJ mice, by human blood cells and human M phi. In this structure-activity relationship study, we found that (i) the p-substitution of the benzoyl group definitely affects the activity to activate C3H/HeN M phi, (ii) the analogs having a methyl or chloro group at the p-position exhibit stronger activity than that of paclitaxel, (iii) there is good correlation between NO and TNF production by the M phi in response to compounds, (iv) the compounds tested do not induce either NO or TNF production by C3H/HeJ M phi or TNF production by human cells, (v) a previous treatment of C3H/HeN M phi with the inactive compounds can hardly affect either paclitaxel- or LPS-induced TNF production by the M phi, (vi) paclitaxel and its analogs marginally affect LPS-induced TNF production by human blood cells, and (vii) there is no correlation between the NO/TNF inducibility to C3H/HeN M phi and growth inhibitory activity against M phi-like J774.1 and J7.DEF3 cells. PMID:9588177

Kirikae, T; Ojima, I; Ma, Z; Kirikae, F; Hirai, Y; Nakano, M

1998-04-28

279

Arsenic toxicity induced endothelial dysfunction and dementia: pharmacological interdiction by histone deacetylase and inducible nitric oxide synthase inhibitors.  

PubMed

Arsenic toxicity has been reported to damage all the major organs including the brain and vasculature. Dementia including Alzheimer's disease (AD) and vascular dementia (VaD) are posing greater risk to the world population as it is now increasing at a faster rate. We have investigated the role of sodium butyrate, a selective histone deacetylase (HDAC) inhibitor and aminoguanidine, a selective inducible nitric oxide synthase (iNOS) inhibitor in pharmacological interdiction of arsenic toxicity induced vascular endothelial dysfunction and dementia in rats. Arsenic toxicity was done by administering arsenic drinking water to rats. Morris water-maze (MWM) test was used for assessment of learning and memory. Endothelial function was assessed using student physiograph. Oxidative stress (aortic superoxide anion, serum and brain thiobarbituric acid reactive species, brain glutathione) and nitric oxide levels (serum nitrite/nitrate) were also measured. Arsenic treated rats have shown impairment of endothelial function, learning and memory, reduction in serum nitrite/nitrate & brain GSH levels along with increase in serum & brain TBARS. Sodium butyrate as well as aminoguanidine significantly convalesce arsenic induced impairment of learning, memory, endothelial function, and alterations in various biochemical parameters. It may be concluded that arsenic induces endothelial dysfunction and dementia, whereas, sodium butyrate, a HDAC inhibitor as well as aminoguanidine, a selective iNOS inhibitor may be considered as potential agents for the management of arsenic induced endothelial dysfunction and dementia. PMID:23921152

Sharma, Bhupesh; Sharma, P M

2013-11-15

280

Evidence against a role for inducible nitric oxide synthase in the hyperdynamic circulation of portal-hypertensive rats  

Microsoft Academic Search

Background\\/Aims Excessive nitric oxide biosynthesis caused by expression of inducible NO synthase has been implicated in the hyperdynamic circulation of portal hypertension. The aim of the study was to investigate whether inducible NO synthase is expressed in portal hypertension and accounts for the hyperdynamic circulation. Methods In study 1, NO synthase activities were measured by the conversion of l-arginine to

Mercedes Fernández; Juan Carlos García-Pagán; Maria Casadevall; Cristina Bernadich; Carlos Piera; Brendan J. R. Whittle; Josep M. Piqué; Jaume Bosch; Juan Rodés

1995-01-01

281

The Protective Role of Endogenously Synthesized Nitric Oxide in Staphylococcal Enterotoxin B-induced Shock in Mice  

Microsoft Academic Search

Summary Nitric oxide (NO) synthesis during experimental endotoxemia has been shown to have both deleterious and beneficial effects. In the present study, we analyzed the in vivo production and the regulatory role of NO in the shock syndrome induced by staphylococcal enterotoxin B (SEB) in mice. First, we found that intraperitoneal administration of 100\\/xg SEB in BALB\\/c mice induced a

Sandrine Florquin; Zoulikka Amraoui; Christine Dubois; Jean Decuyper; Michel Goldman

1994-01-01

282

Interleukin-33 Increases Antibacterial Defense by Activation of Inducible Nitric Oxide Synthase in Skin  

PubMed Central

Interleukin-33 (IL-33) is associated with multiple diseases, including asthma, rheumatoid arthritis, tissue injuries and infections. Although IL-33 has been indicated to be involved in Staphylococcus aureus (S. aureus) wound infection, little is known about how IL-33 is regulated as a mechanism to increase host defense against skin bacterial infections. To explore the underlying intricate mechanism we first evaluated the expression of IL-33 in skin from S. aureus-infected human patients. Compared to normal controls, IL-33 was abundantly increased in skin of S. aureus-infected patients. We next developed a S. aureus cutaneous infection mouse model and found that IL-33 was significantly increased in dermal macrophages of infected mouse skin. The expression of IL-33 by macrophages was induced by staphylococcal peptidoglycan (PGN) and lipoteichoic acid (LTA) via activation of toll-like receptor 2(TLR2) –mitogen-activated protein kinase (MAPK)-AKT-signal transducer and activator of transcription 3(STAT3) signaling pathway as PGN and LTA failed to induce IL-33 in Tlr2-deficient peritoneal macrophages, and MAPK,AKT, STAT3 inhibitors significantly decreased PGN- or LTA-induced IL-33. IL-33, in turn, acted on macrophages to induce microbicidal nitric oxygen (NO) release. This induction was dependent on inducible nitric oxide synthase (iNOS) activation, as treatment of macrophages with an inhibitor of iNOS, aminoguanidine, significantly decreased IL-33-induced NO release. Moreover, aminoguanidine significantly blocked the capacity of IL-33 to inhibit the growth of S. aureus, and IL-33 silencing in macrophages significantly increased the survival of S. aureus in macrophages. Furthermore, the administration of IL-33-neutralizing antibody into mouse skin decreased iNOS production but increased the survival of S. aureus in skin. These findings reveal that IL-33 can promote antimicrobial capacity of dermal macrophages, thus enhancing antimicrobial defense against skin bacterial infections. PMID:24586149

Jiang, Ziwei; Zhang, Tian; Wang, Yue; Li, Zhiheng; Wu, Yelin; Ji, Shizhao; Xiao, Shichu; Ryffel, Bernhard; Radek, Katherine A.; Xia, Zhaofan; Lai, Yuping

2014-01-01

283

Purple sweet potato color suppresses lipopolysaccharide-induced acute inflammatory response in mouse brain.  

PubMed

The neuroprotective effects of purple sweet potato color (PSPC), which is natural anthocyanin food colors, have been investigated in mice treated with lipopolysaccharide (LPS). In behavioral tests, oral administration of PSPC could significantly reverse the impairment of motor and exploration behavior induced by LPS in the open field tasks, and also improve learning and memory ability in step-through tests. Western blot analysis indicated that PSPC significantly suppressed LPS-induced cyclooxygenase-2 (COX-2) and inducible nitric oxide synthases (iNOS) expression in mouse brain. PSPC also markedly decreased the overproduction of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta) and interleukin-6 (IL-6) in LPS-stimulated mouse brain. Mechanistically, PSPC strongly inhibited LPS-induced phosphorylated extracellular signal-regulated kinase (ERK) and phosphorylated c-Jun N-terminal kinase (JNK) expression and nuclear factor kappa B (NF-kappaB) activation. Taken together, these data suggest that PSPC may be useful for mitigating inflammatory brain diseases by the inhibition of proinflammatory molecule production, at least in part, through blocking ERK, JNK and NF-kappaB signaling. PMID:19941923

Wang, Yong-Jian; Zheng, Yuan-Lin; Lu, Jun; Chen, Guo-Qing; Wang, Xiao-Hui; Feng, Jie; Ruan, Jie; Sun, Xiao; Li, Chun-Xiang; Sun, Qiu-Ju

2010-02-01

284

Pharmacological characterization of KLYP961, a dual inhibitor of inducible and neuronal nitric-oxide synthases.  

PubMed

Nitric oxide (NO) derived from neuronal nitric-oxide synthase (nNOS) and inducible nitric-oxide synthase (iNOS) plays a key role in various pain and inflammatory states. KLYP961 (4-((2-cyclobutyl-1H-imidazo[4,5-b]pyrazin-1-yl)methyl)-7,8-difluoroquinolin-2(1H)-one) inhibits the dimerization, and hence the enzymatic activity of human, primate, and murine iNOS and nNOS (IC(50) values 50-400 nM), with marked selectivity against endothelial nitric-oxide synthase (IC(50) >15,000 nM). It has ideal drug like-properties, including excellent rodent and primate pharmacokinetics coupled with a minimal off-target activity profile. In mice, KLYP961 attenuated endotoxin-evoked increases in plasma nitrates, a surrogate marker of iNOS activity in vivo, in a sustained manner (ED(50) 1 mg/kg p.o.). KLYP961 attenuated pain behaviors in a mouse formalin model (ED(50) 13 mg/kg p.o.), cold allodynia in the chronic constriction injury model (ED(50) 25 mg/kg p.o.), or tactile allodynia in the spinal nerve ligation model (ED(50) 30 mg/kg p.o.) with similar efficacy, but superior potency relative to gabapentin, pregabalin, or duloxetine. Unlike morphine, the antiallodynic activity of KLYP961 did not diminish upon repeated dosing. KLYP961 also attenuated carrageenin-induced edema and inflammatory hyperalgesia and writhing response elicited by phenylbenzoquinone with efficacy and potency similar to those of celecoxib. In contrast to gabapentin, KLYP961 did not impair motor coordination at doses as high as 1000 mg/kg p.o. KLYP961 also attenuated capsaicin-induced thermal allodynia in rhesus primates in a dose-related manner with a minimal effective dose (? 10 mg/kg p.o.) and a greater potency than gabapentin. In summary, KLYP961 represents an ideal tool with which to probe the physiological role of NO derived from iNOS and nNOS in human pain and inflammatory states. PMID:21036913

Symons, Kent T; Nguyen, Phan M; Massari, Mark E; Anzola, John V; Staszewski, Lena M; Wang, Li; Yazdani, Nahid; Dorow, Steven; Muhammad, Jerry; Sablad, Marciano; Rozenkrants, Natasha; Bonefous, Celine; Payne, Joseph E; Rix, Peter J; Shiau, Andrew K; Noble, Stewart A; Smith, Nicholas D; Hassig, Christian A; Zhang, Yan; Rao, Tadimeti S

2011-02-01

285

Role of nitric oxide in adenosine-induced vasodilation in humans  

NASA Technical Reports Server (NTRS)

Vasodilation is one of the most prominent effects of adenosine and one of the first to be recognized, but its mechanism of action is not completely understood. In particular, there is conflicting information about the potential contribution of endothelial factors. The purpose of this study was to explore the role of nitric oxide in the vasodilatory effect of adenosine. Forearm blood flow responses to intrabrachial adenosine infusion (125 microg/min) were assessed with venous occlusion plethysmography during intrabrachial infusion of saline or the nitric oxide synthase inhibitor NG-monomethyl-L-arginine (L-NMMA) (12.5 mg/min). Intrabrachial infusions of acetylcholine (50 microg/min) and nitroprusside (3 microg/min) were used as a positive and negative control, respectively. These doses were chosen to produce comparable levels of vasodilation. In a separate study, a second saline infusion was administered instead of L-NMMA to rule out time-related effects. As expected, pretreatment with L-NMMA reduced acetylcholine-induced vasodilation; 50 microg/min acetylcholine increased forearm blood flow by 150+/-43% and 51+/-12% during saline and L-NMMA infusion, respectively (P<.01, n=6). In contrast, L-NMMA did not affect the increase in forearm blood flow produced by 3 microg/min nitroprusside (165+/-30% and 248+/-41% during saline and L-NMMA, respectively) or adenosine (173+/-48% and 270+/-75% during saline and L-NMMA, respectively). On the basis of our observations, we conclude that adenosine-induced vasodilation is not mediated by nitric oxide in the human forearm.

Costa, F.; Biaggioni, I.; Robertson, D. (Principal Investigator)

1998-01-01

286

Production of angiogenic activity by human monocytes requires an L-arginine/nitric oxide-synthase-dependent effector mechanism.  

PubMed Central

Human monocytes (M phi) require stimulation with substances such as bacterial endotoxin [LPS (lipopolysaccharide)] to produce angiogenic activity. In this study, we report that stimulation of M phi with LPS (5 micrograms/ml) in the absence of L-arginine greatly reduced their production of angiogenic activity, as assessed in vivo in rat corneas and in vitro by chemotaxis of human umbilical vein endothelial cells (HU-VECs). D-Arginine did not substitute for L-arginine in the production of angiogenic activity. The nitric oxide synthase (NO synthase, EC 1.14-13.39) inhibitors NG-monomethyl-L-arginine (L-NMMA) and NG-nitro-L-arginine methyl ester (L-NAME) both inhibited the production of angiogenic activity by LPS-stimulated M phi in the presence of L-arginine, suggesting the involvement of this enzyme in the pathway that generates angiogenic activity. Neither of these substances directly inhibited the M phi-derived angiogenic activity. LPS-induced production of the cytokines tumor necrosis factor alpha (TNF-alpha) and interleukin 8 (IL-8) was not significantly reduced when M phi were incubated in the absence of L-arginine. Similarly, L-NMMA and L-NAME did not significantly reduce the LPS-induced production of these cytokines by M phi in the presence of L-arginine. These results suggest that the LPS-stimulation-dependent generation of angiogenic activity by M phi requires an L-arginine-dependent NO-synthase effector mechanism that may be independent of the generation of TNF-alpha and IL-8. Images PMID:7514298

Leibovich, S J; Polverini, P J; Fong, T W; Harlow, L A; Koch, A E

1994-01-01

287

Effects of cobalt chloride on nitric oxide and cytokines/chemokines production in microglia.  

PubMed

The involvement of microglial activation in metal neurotoxicity is becoming increasingly recognized. Some metal ions, such as zinc (II) and manganese (II), have been recently reported as microglial activators to induce the release of inflammatory mediators including cytokines, chemokines and nitric oxide (NO) which are involved in the pathogenesis of neurological diseases. Cobalt is essential for human life. However, excessive cobalt is cytotoxic and neurotoxic. In the present study, we determined cobalt-induced production of NO and cytokines/chemokines in N9 cells, a murine microglial cell line. High levels of cobalt significantly up-regulated iNOS mRNA and protein expression, which resulted in the release of NO. Cobalt induced the production of tumor necrosis factor ? (TNF-?) and interleukin-6 (IL-6) in a concentration- and time-dependent manner in both N9 cells and primary mouse microglia and increased lipopolysaccharides (LPS)-induced cytokine production. Further study showed that cobalt induced cytokine production by a mechanism involving both nuclear factor kappa B (NF-?B) and p38 mitogen-activated protein kinase (MAPK) signaling pathways. The involvement of reactive oxygen species (ROS) in microglial activation was also confirmed. These findings suggested that cobalt neurotoxicity should be attributed not only directly to neuronal damage but also indirectly to microglial activation which might potentiate neuronal injury via elevation of proinflammatory mediator levels. PMID:22472292

Mou, Yan Hua; Yang, Jing Yu; Cui, Nan; Wang, Ji Ming; Hou, Yue; Song, Shuang; Wu, Chun Fu

2012-05-01

288

Radiation-induced nitric oxide mitigates tumor hypoxia and radioresistance in a murine SCCVII tumor model  

SciTech Connect

Highlights: •IR-induced NO increased tissue perfusion and pO{sub 2}. •IR increased NO production in tumors without changes in the mRNA and protein levels of NOS isoforms. •NOS activity assay showed that IR upregulated eNOS activity in tumors. •IR-induced NO decreased tumor hypoxia and altered tumor radiosensitivity. -- Abstract: Tumor hypoxia, which occurs mainly as a result of inadequate tissue perfusion in solid tumors, is a well-known challenge for successful radiotherapy. Recent evidence suggests that ionizing radiation (IR) upregulates nitric oxide (NO) production and that IR-induced NO has the potential to increase intratumoral circulation. However, the kinetics of NO production and the responsible isoforms for NO synthase in tumors exposed to IR remain unclear. In this study, we aimed to elucidate the mechanism by which IR stimulates NO production in tumors and the effect of IR-induced NO on tumor radiosensitivity. Hoechst33342 perfusion assay and electron spin resonance oxymetry showed that IR increased tissue perfusion and pO{sub 2} in tumor tissue. Immunohistochemical analysis using two different hypoxic probes showed that IR decreased hypoxic regions in tumors; treatment with a nitric oxide synthase (NOS) inhibitor, L-NAME, abrogated the effects of IR. Moreover, IR increased endothelial NOS (eNOS) activity without affecting its mRNA or protein expression levels in SCCVII-transplanted tumors. Tumor growth delay assay showed that L-NAME decreased the anti-tumor effect of fractionated radiation (10 Gy × 2). These results suggested that IR increased eNOS activity and subsequent tissue perfusion in tumors. Increases in intratumoral circulation simultaneously decreased tumor hypoxia. As a result, IR-induced NO increased tumor radiosensitivity. Our study provides a new insight into the NO-dependent mechanism for efficient fractionated radiotherapy.

Nagane, Masaki, E-mail: nagane@vetmed.hokudai.ac.jp [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan)] [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan); Yasui, Hironobu, E-mail: yassan@vetmed.hokudai.ac.jp [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan)] [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan); Yamamori, Tohru, E-mail: yamamorit@vetmed.hokudai.ac.jp [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan)] [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan); Zhao, Songji, E-mail: zsi@med.hokudai.ac.jp [Department of Tracer Kinetics and Bioanalysis, Graduate School of Medicine, Hokkaido University, Sapporo (Japan)] [Department of Tracer Kinetics and Bioanalysis, Graduate School of Medicine, Hokkaido University, Sapporo (Japan); Kuge, Yuji, E-mail: kuge@med.hokudai.ac.jp [Central Institute of Isotope Science, Hokkaido University, Sapporo (Japan)] [Central Institute of Isotope Science, Hokkaido University, Sapporo (Japan); Tamaki, Nagara, E-mail: natamaki@med.hokudai.ac.jp [Department of Nuclear Medicine, Graduate School of Medicine, Hokkaido University, Sapporo (Japan)] [Department of Nuclear Medicine, Graduate School of Medicine, Hokkaido University, Sapporo (Japan); Kameya, Hiromi, E-mail: kameya@affrc.go.jp [Food Safety Division, National Food Research Institute, Tsukuba (Japan)] [Food Safety Division, National Food Research Institute, Tsukuba (Japan); Nakamura, Hideo, E-mail: naka@science-edu.org [Department of Chemistry, Hokkaido University of Education, Hakodate (Japan)] [Department of Chemistry, Hokkaido University of Education, Hakodate (Japan); Fujii, Hirotada, E-mail: hgfujii@sapmed.ac.jp [Center for Medical Education, Sapporo Medical University, Sapporo (Japan)] [Center for Medical Education, Sapporo Medical University, Sapporo (Japan); Inanami, Osamu, E-mail: inanami@vetmed.hokudai.ac.jp [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan)] [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan)

2013-08-02

289

Prostaglandins mediate bradykinin-induced reduction of exhaled nitric oxide in asthma.  

PubMed

Bradykinin (BK) is a mediator of inflammation in asthma with potent bronchoconstrictor actions. Endogenous release of nitric oxide may inhibit BK-induced bronchoconstriction. This study investigated whether bradykinin inhalation could modulate exhaled NO levels in normal and asthmatic subjects, and whether the bradykinin-induced effects were mediated through the production of cyclo-oxygenase products in patients with asthma, by studying the effect of the cyclo-oxygenase inhibitor, L-acetylsalicylic acid (L-ASA). Exhaled NO concentration and forced expiratory volume in one second (FEV1) were measured by chemiluminescence following inhalation of increasing concentrations of BK. In asthmatics (n=11), BK induced a dose-dependent decrease in exhaled NO concentration from 21.3+/-1.6 to 6.+/-0.5 parts per billion (ppb) (p<0.01) at the highest concentration, associated with a significant fall in FEV1. In normal subjects (n=10), the exhaled NO concentration fell from 7.2+/-0.13 to 4.3+/-0.51 ppb (p<0.001) 15 min, after a single inhalation of BK, but without a significant change in FEV1. In asthmatic subjects, pretreatment with inhaled L-ASA (90 x mg x mL(-1), 4 mL) did not alter exhaled NO levels, but prevented a BK-induced fall in exhaled NO concentration, as indicated by a significant increase in exhaled NO levels at the provocative concentration of BK causing a 20% fall in FEV1, (5.7 +/- 0.94 ppb after placebo and 12.0 +/- 1.8 ppb after L-ASA; p<0.05). L-ASA significantly reduced bronchial responsiveness to BK 3.9-fold (p<0.01). Inhaled bradykinin induced bronchoconstriction and a reduction in exhaled nitric oxide levels in asthmatic subjects, an effect that is partly mediated by cyclo-oxygenase products. PMID:10596684

Kharitonov, S A; Sapienza, M M; Chung, K F; Barnes, P J

1999-11-01

290

Ginsenoside Rg3 inhibits phenylephrine-induced vascular contraction through induction of nitric oxide synthase  

PubMed Central

Ginsenoside Rg3 (Rg3) isolated from Panax ginseng relaxes vessels and exerts a cytoprotective effect. In view of the fact that nitric oxide (NO) is involved in vascular hyporeactivity and immunostimulation, the effects of total ginsenosides (GS) and Rg3 on the vascular responses and the expression of inducible nitric oxide synthase (iNOS) were investigated. Vasocontraction of endothelium-denuded aortic ring was induced by phenylephrine with or without GS or Rg3. The expression of iNOS was assessed by Western blot and RT–PCR analyses. NF-?B activation was monitored by gel shift, immunoblot and immunocytochemical analyses. Incubation of the endothelium-denuded aortic ring with GS or Rg3 inhibited phenylephrine-induced vasocontraction, which was abrogated by NOS inhibition. GS or Rg3 increased NO production in aortic rings, but Rb1, Rc, Re and Rg1 had no effect. Aortic rings obtained from rats treated with GS or Rg3 responded to phenylnephrine to a lesser extent, while producing NO to a larger extent, than those from control animals. GS or Rg3 induced iNOS in vascular smooth muscle. Rg3 induced iNOS with increase in NO production in Raw264.7 cells. Rg3 increased NF-?B DNA binding, whose band was supershifted with anti-p65 and anti-p50 antibodies, and elicited p65 nuclear translocation, which was accompanied by phosphorylation and degradation of I-?B?. PKC regulated iNOS induction by Rg3. In conclusion, Rg3 relaxes vessels as a consequence of NO production, to which iNOS induction contributes, and iNOS induction by Rg3 accompanied NF-?B activation, which involves phosphorylation and degradation of I-?B? and nuclear translocation of p65. PMID:14534150

Kim, Nak Doo; Kim, Eun Mi; Kang, Keon Wook; Cho, Min Kyung; Choi, So Yeon; Kim, Sang Geon

2003-01-01

291

Curcumin ameliorates ethanol-induced memory deficits and enhanced brain nitric oxide synthase activity in mice.  

PubMed

Ethanol consumption has well-known deleterious effects on memory. However, the mechanism by which ethanol exerts its effects on memory has received little attention, which has retarded the identification and development of effective therapeutic strategies against ethanol toxicity. The aim of this study was to explore the neuronal mechanisms underlying the protective action of curcumin, a natural polyphenolic compound of Curcuma longa, against ethanol-induced memory deficits. Adult mice were pretreated with curcumin (40 mg/kg, i.p.) before administration of ethanol (1 g/kg, i.p.) for the memory acquisition measurement, or were sacrificed 30 min later for evaluation of regional brain differences in the nitric oxide synthase (NOS) activity and nitric oxide (NO) concentration. The results showed that pretreatment with curcumin significantly ameliorated the memory deficits resulting from acute ethanol administration to mice in the novel object recognition and inhibitory avoidance tasks. Furthermore, acute ethanol treatment increased the NOS activity and NO production in brain regions associated with memory including prefrontal cortex (PFC), amygdala and hippocampus, while this enhancement was suppressed by pretreatment with curcumin. Taken together, these results suggest that the protective effects of curcumin on acute ethanol-induced memory deficits are mediated, at least in part, by suppressing NOS activity in the brain of mice. Thus, manipulation of the NOS/NO signaling pathway might be beneficial for the prevention of ethanol toxicity. PMID:23500667

Yu, Shu Yan; Gao, Rui; Zhang, Lin; Luo, Junxia; Jiang, Hong; Wang, Shuanglian

2013-07-01

292

A common fungal volatile organic compound induces a nitric oxide mediated inflammatory response in Drosophila melanogaster.  

PubMed

Using a Drosophila model, we previously demonstrated truncated life span and neurotoxicity with exposure to 1-octen-3-ol, the volatile organic compound (VOC) responsible for much of the musty odor found in mold-contaminated indoor spaces. In this report, using biochemical and immunological assays, we show that exposure to 0.5?ppm 1-octen-3-ol induces a nitric oxide (NO) mediated inflammatory response in hemocytes, Drosophila innate immune cells. Moreover, exposed Drosophila brains show increased peroxynitrite expression. An increase in nitrite levels is observed with toluene and 1-octen-3-ol but not with 1-butanol. Pharmacological inhibitors of nitric oxide synthase (NOS) namely, L-NAME, D-NAME and minocycline, and NOS mutants show improvements of life span among 1-octen-3-ol exposed flies. Exposure to 1-octen-3-ol also induces NOS expression in larval tracheal tissues and remodels tracheal epithelial lining. These findings suggest a possible mechanistic basis for some of the reported adverse health effects attributed to mold exposure and demonstrates the utility of this in vivo Drosophila model to complement existing model systems for understanding the role of inflammation in VOC-mediated toxicity. PMID:24509902

Inamdar, Arati A; Bennett, Joan W

2014-01-01

293

A common fungal volatile organic compound induces a nitric oxide mediated inflammatory response in Drosophila melanogaster  

PubMed Central

Using a Drosophila model, we previously demonstrated truncated life span and neurotoxicity with exposure to 1-octen-3-ol, the volatile organic compound (VOC) responsible for much of the musty odor found in mold-contaminated indoor spaces. In this report, using biochemical and immunological assays, we show that exposure to 0.5?ppm 1-octen-3-ol induces a nitric oxide (NO) mediated inflammatory response in hemocytes, Drosophila innate immune cells. Moreover, exposed Drosophila brains show increased peroxynitrite expression. An increase in nitrite levels is observed with toluene and 1-octen-3-ol but not with 1-butanol. Pharmacological inhibitors of nitric oxide synthase (NOS) namely, L-NAME, D-NAME and minocycline, and NOS mutants show improvements of life span among 1-octen-3-ol exposed flies. Exposure to 1-octen-3-ol also induces NOS expression in larval tracheal tissues and remodels tracheal epithelial lining. These findings suggest a possible mechanistic basis for some of the reported adverse health effects attributed to mold exposure and demonstrates the utility of this in vivo Drosophila model to complement existing model systems for understanding the role of inflammation in VOC-mediated toxicity. PMID:24509902

Inamdar, Arati A.; Bennett, Joan W.

2014-01-01

294

Inhibition of inducible nitric oxide synthase and osteoclastic differentiation by Atractylodis Rhizoma Alba extract  

PubMed Central

Background: Atractylodis Rhizoma Alba (ARA) has been used in Korean folk medicine for constipation, dizziness, and anticancer agent. In the present study, we performed to test whether the methanolic extract of ARA has antioxidant and antiosteoclastogenesis activity in RAW 264.7 macrophage cells. Materials and Methods: Antioxidant capacities were tested by measuring free radical scavenging activity, nitric oxide (NO) levels, reducing power, and inducible nitric oxide synthase (iNOS) expression in response to lipopolysaccharides (LPS). Antiosteoclastogenesis activity was evaluated by performing tartrate-resistant acid phosphatase assay in RAW 264.7 macrophage cells. Results: The extract exerted significant 1,1-diphenyl-2-picrylhydrazyl and NO radical scavenging activity, and it exerted dramatic reducing power. Induction of iNOS and NO by LPS in RAW 264.7 cells was significantly inhibited by the extract, suggesting that the ARA extract inhibits NO production by suppressing iNOS expression. Strikingly, the ARA extracts substantially inhibited the receptor activator of NF-?B ligand-induced osteclastic differentiation of LPS-activated RAW 264.7 cells. The ARA extract contains a significant amount of antioxidant components, including phenolics, flavonoids and anthocyanins. Conclusion: These results suggest that the methanolic extract of ARA exerts significant antioxidant activities potentially via inhibiting free radicals and iNOS induction, thereby leading to the inhibition of osteoclastogenesis.

Choi, Sung-Ho; Kim, Sung-Jin

2014-01-01

295

Is there a role for nitric oxide in methamphetamine-induced dopamine terminal degeneration?  

PubMed

Methamphetamine (METH) abuse results in long-term damage to the dopaminergic system, manifesting as decreases in dopamine (DA) tissue content, DA transporter binding, as well as tyrosine hydroxylase and vesicular monoamine transporter immunostaining. However, the exact cascade of events that ultimately result in this damage has not been clearly elucidated. One factor that has been heavily implicated in METH-induced DA terminal degeneration is the production of nitric oxide (NO). Unfortunately, many of the studies attempting to clarify the role of NO in METH-induced neurotoxicity have been confounded by issues such as the disruption of METH-induced hyperthermia, preventing the formation of strong conclusions. As a result, there is a body of work suggesting that NO is sufficient for METH-induced neurotoxicity, while other studies suggest that NO does not play a role in METH-induced degeneration of DA nerve terminals. This review summarizes the existing studies investigating the role of NO in METH-induced neurotoxicity, and argues that while NO may be necessary for METH-induced neurotoxicity, it is not sufficient. Finally, important areas of future investigation are highlighted and discussed. PMID:23918001

Friend, Danielle M; Fricks-Gleason, Ashley N; Keefe, Kristen A

2014-02-01

296

Beneficial Effects of Fractions of Nardostachys jatamansi on Lipopolysaccharide-Induced Inflammatory Response  

PubMed Central

It has been previously shown that Nardostachys jatamansi (NJ) exhibits anti-inflammatory properties against lipopolysaccharide (LPS) challenges. However, the potency of NJ constituents against LPS-induced inflammatory responses has not been examined. In this present study, we determined which NJ extract fractions exhibit inhibitory effects against LPS-induced inflammatory responses. Among the NJ fractions, NJ-1, NJ-3, NJ-4, and NJ-6 inhibited LPS-induced production of NO. The NJ-3, NJ-4, and NJ-6 fractions also inhibited the production of cytokines, such as IL-1?, IL-6, and TNF-?. However, NJ-1, NJ-3, NJ-4, and NJ-6 showed differential inhibitory mechanisms against LPS-induced inflammatory responses. NJ-1, NJ-3, and NJ-4 inhibited LPS-induced activation of c-jun NH2-terminal kinase (JNK) and p38 but did not affect activation of extracellular signal-regulated kinase (ERK) or NF-?B. On the other hand, NJ-6 inhibited activation of MAPKs and NF-?B. In addition, in vivo experiments revealed that administration of NJ-1, NJ-3, NJ-4, and NJ-6 reduced LPS-induced endotoxin shock, with NJ-6 especially showing a marked protective effect. Taken together, these results provide the evidence for the potential of selective NJ fractions against LPS-induced inflammation. Thus, it will be advantageous to further isolate and determine single effective compounds from these potent fractions. PMID:24795771

Heo, Kwang-Ho; Choi, Sun Bok; Jo, Il-Joo; Kim, Dong-Goo; Shin, Joon-Yeon; Seo, Seung-Hee; Park, Kyoung-Chel; Lee, Dong-Sung; Oh, Hyuncheol; Kim, Youn-Chul; Song, Ho-Joon; Shin, Byung-Cheul

2014-01-01

297

RNA interference-produced autoregulation of inducible nitric oxide synthase expression  

PubMed Central

Vector-mediated delivery of short-hairpin RNA (shRNA) to regulate gene expression holds a great therapeutic promise. We hypothesize that gene expression can be autoregulated with RNA interference. We used inducible nitric oxide synthase (iNOS) as a gene model to test this hypothesis. Lipopolysaccharide dose-dependently increased iNOS in rat aortic smooth muscle cells and the nitrite production from these cells. These increases were attenuated in cells transfected with plasmids containing code for iNOS shRNA whose expression was controlled by an iNOS promoter. The production of shRNA was lipopolysaccharide dose-dependent. The lipopolysaccharide-induced iNOS expression in rat C6 glioma cells also was attenuated by transfection with plasmids containing the iNOS shRNA code. These results provide proof-of-concept evidence for using RNA interference technique to achieve autoregulation of gene expression. PMID:21741974

Feng, Chenzhuo; Cao, Lin; Zuo, Zhiyi

2011-01-01

298

The ac Stark effect in nitric oxide induced by rapidly swept continuous wave quantum cascade lasers.  

PubMed

A large ac Stark effect has been observed when nitric oxide, at low pressure in a long optical path (100 m) Herriot cell, is subjected to infrared radiation from a rapidly swept, continuous wave infrared quantum cascade laser. As the frequency sweep rate of the laser is increased, an emission signal induced by rapid passage occurs after the laser frequency has passed through the resonance of 1-0 R(11.5)(3/2 /)molecular absorption line. At very high sweep rates a laser field-induced splitting of the absorptive part of the signal is observed, due to the ac Stark effect. This splitting is related to the Autler-Townes mixing of the e, f lambda doublet components of the 1-0 R(11.5)(3/2) transition, which lie under the Doppler broadened envelope. PMID:22583241

Duxbury, Geoffrey; Kelly, James F; Blake, Thomas A; Langford, Nigel

2012-05-01

299

Expression of Inducible Nitric Oxide Synthase (iNOS) in Microglia of the Developing Quail Retina  

PubMed Central

Inducible nitric oxide synthase (iNOS), which produce large amounts of nitric oxide (NO), is induced in macrophages and microglia in response to inflammatory mediators such as LPS and cytokines. Although iNOS is mainly expressed by microglia that become activated in different pathological and experimental situations, it was recently reported that undifferentiated amoeboid microglia can also express iNOS during normal development. The aim of this study was to investigate the pattern of iNOS expression in microglial cells during normal development and after their activation with LPS by using the quail retina as model. iNOS expression was analyzed by iNOS immunolabeling, western-blot, and RT-PCR. NO production was determined by using DAR-4M AM, a reliable fluorescent indicator of subcellular NO production by iNOS. Embryonic, postnatal, and adult in situ quail retinas were used to analyze the pattern of iNOS expression in microglial cells during normal development. iNOS expression and NO production in LPS-treated microglial cells were investigated by an in vitro approach based on organotypic cultures of E8 retinas, in which microglial cell behavior is similar to that of the in situ retina, as previously demonstrated in our laboratory. We show here that amoeboid microglia in the quail retina express iNOS during normal development. This expression is stronger in microglial cells migrating tangentially in the vitreal part of the retina and is downregulated, albeit maintained, when microglia differentiate and become ramified. LPS treatment of retina explants also induces changes in the morphology of amoeboid microglia compatible with their activation, increasing their lysosomal compartment and upregulating iNOS expression with a concomitant production of NO. Taken together, our findings demonstrate that immature microglial cells express iNOS during normal development, suggesting a certain degree of activation. Furthermore, LPS treatment induces overactivation of amoeboid microglia, resulting in a significant iNOS upregulation. PMID:25170849

Sierra, Ana; Navascues, Julio; Cuadros, Miguel A.; Calvente, Ruth; Martin-Oliva, David; Ferrer-Martin, Rosa M.; Martin-Estebane, Maria; Carrasco, Maria-Carmen; Marin-Teva, Jose L.

2014-01-01

300

6-Dehydrogingerdione restrains lipopolysaccharide-induced inflammatory responses in RAW 264.7 macrophages.  

PubMed

6-Dehydrogingerdione (6-DG), one important component of ginger, has been reported to possess some medical effects, such as antitumor and antiatherosclerosis. Herein, the anti-inflammatory effects of 6-DG against lipopolysaccharides (LPS) induced pro-inflammation mediators in RAW 264.7 cells were investigated. Results show that 6-DG significantly attenuated inducible nitric oxide synthase (iNOS, NOS2), cyclooxygenase-2 (COX-2), interleukin-1? (IL-1?), interleukin 6 (IL-6), and tumor necrosis factor-? (TNF-?) in the LPS-mediated murine macrophages (RAW 264.7 cells). 6-DG inhibited LPS-induced phosphorylation of both p38 and nuclear factor of ? light polypeptide gene enhancer in B-cells inhibitor-? (I?B?), which further prevented p-p65 nuclear factor-?B (NF-?B-p65) translocation to the nucleus. Moreover, 6-DG increased the ratio of phosphorylated signal transducers and activators of transcription 1 (p-STAT1)/p-STAT3 and down-regulated the gene expression of IL-1?, IL-6, and IL-10. PMID:25162585

Huang, Shih-Han; Lee, Chien-Hsing; Wang, Hui-Min; Chang, Yu-Wei; Lin, Chun-Yu; Chen, Chung-Yi; Chen, Yen-Hsu

2014-09-17

301

Sphingosine 1-phosphate induces endothelial nitric-oxide synthase activation through phosphorylation in human corpus cavernosum.  

PubMed

Sphingosine 1-phosphate (S1P) is the natural ligand for a specific G protein-coupled receptors. In endothelial cells, S1P has been shown to modulate the activity of the endothelial nitric-oxide synthase (eNOS) through phosphorylation operated by Akt. Nitric oxide (NO) produced by neuronal nitric-oxide synthase and eNOS plays a central role in triggering and maintaining penile erection. This study has assessed the possibility of a similar cross-talk between eNOS and S1P in human corpus cavernosum and whether this interaction is connected to penile vascular response. Quantitative reverse transcription-polymerase chain reaction demonstrated the presence of S1P(1), S1P(2), and S1P(3) receptors in both the human corpus cavernosum (HCC) and the penile artery. S1P on its own did not relax or contract HCC strips, but on the other hand, incubation with S1P (0.1 microM) caused a 6-fold increase in relaxation induced by a subliminal dose of acetylcholine. This effect is dependent upon eNOS activation through an Akt-dependent phosphorylation, as demonstrated by pharmacological modulation with l-nitroarginine methyl ester and wortmannin and by Western blot studies. In human tissue, S1P seems to be the possible candidate for the activation of the eNOS calcium-independent pathway. This pathway may represent a new therapeutic area of intervention in erectile dysfunction (ED) to develop a way to selectively promote NO production at the endothelial level. This approach could also be used to enhance phosphodiesterase 5 therapy in patients with ED that are poor responders, such as in the case of diabetes. PMID:16234413

di Villa Bianca, Roberta d'Emmanuele; Sorrentino, Raffaella; Sorrentino, Rosalinda; Imbimbo, Ciro; Palmieri, Alessandro; Fusco, Ferdinando; Maggi, Mario; De Palma, Raffaele; Cirino, Giuseppe; Mirone, Vincenzo

2006-02-01

302

Inhibition of Lipopolysaccharide-Induced Cyclooxygenase2 and Inducible Nitric Oxide Synthase Expression by 4-[(2?-O-acetyl-?-L-Rhamnosyloxy)Benzyl]Isothiocyanate from Moringa oleifera  

Microsoft Academic Search

Moringa oleifera Lamarck is commonly consumed for nutritional or medicinal properties. We recently reported the isolation and structure elucidation of novel bioactive phenolic glycosides, including 4-[(2?-O-acetyl-?-L-rhamnosyloxy)benzyl]isothiocyanate (RBITC), which was found to suppress inducible nitric oxide synthase (iNOS) expression and nitric oxide (NO) production in lipopolysaccharide-stimulated RAW 264.7 mouse macrophage cells. Inhibitors of proteins such as cyclooxygenase-2 (COX-2) and iNOS are

Eun-Jung Park; Sarot Cheenpracha; Leng Chee Chang; Tamara P. Kondratyuk; John M. Pezzuto

2011-01-01

303

Forsythiaside attenuates lipopolysaccharide-induced inflammatory responses in the bursa of Fabricius of chickens by downregulating the NF-?B signaling pathway  

PubMed Central

Forsythiaside, a phenylethanoside product isolated from air-dried fruits of Forsythia suspensa, has been demonstrated to exhibit antioxidant, antibacterial and anti-inflammatory activities in vitro. However, its mechanism and the effects of lipopolysaccharide (LPS)-induced injury on the bursa of Fabricius (BF) of chickens are poorly understood. The present study aimed to investigate the anti-inflammatory effects of forsythiaside on LPS-induced acute inflammation. In addition, the potential molecular mechanisms of forsythiaside were analyzed in the BF, a special immune organ in chickens. Forty 15-day-old chickens were randomly divided into control, LPS and LPS plus forsythiaside (30 or 60 mg/kg) groups (n=10 for each group). In the LPS plus forsythiaside (30 or 60 mg/kg) groups, the chickens were orally administered with forsythiaside at doses of 30 and 60 mg/kg for seven days. At 21 days old, the chickens were intravenously injected with 200 ?g/kg body weight LPS. Chickens in the control and LPS groups were only administered with vehicle or LPS, respectively, at day 21. At 3 h post-injection, the body temperature and nitric oxide (NO) levels were analyzed. In addition, the levels and mRNA expression of pro-inflammatory cytokines, including tumor necrosis factor-? (TNF-?), interleukin-6 (IL-6) and IL-1?, and the mRNA expression of nuclear factor-?B (NF-?B), cyclooxygenase-2 (COX-2) and inducible NO synthase (iNOS), were examined in the BFs isolated from the chickens. The results revealed that forsythiaside was able to attenuate the LPS-induced inflammatory responses in the BFs of the chickens. The mechanisms by which forsythiaside exerted its anti-inflammatory effect were found to correlate with the inhibition of IL-6, IL-1?, TNF-? and COX-2 production, via the inactivation of NF-?B, indicating that the NF-?B-iNOS-NO signaling pathway may be important in this process. PMID:24348786

CHENG, GUANGDONG; ZHAO, YULIAN; LI, HE; WU, YUE; LI, XIANXIAN; HAN, QIANG; DAI, CHONGSHAN; LI, YANHUA

2014-01-01

304

Increased expression and cellular localization of inducible nitric oxide synthase and cyclooxygenase 2 in Helicobacter pylori gastritis  

Microsoft Academic Search

Background & Aims: Inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 are important regulators of mucosal inflammation and epithelial cell growth. To determine the role of iNOS and COX-2 in Helicobacter pylori–induced tissue injury, we compared their gene expression in H. pylori–induced gastritis with that in normal gastric mucosa and in non–H. pylori gastritis. Methods: In 43 patients, we assessed

Sidong Fu; Kalathur S. Ramanujam; Annie Wong; George T. Fantry; Cinthia B. Drachenberg; Stephen P. James; Stephen J. Meltzer; Keith T. Wilson

1999-01-01

305

Manganese-induced oxidative stress in two ontogenetic stages of chamomile and amelioration by nitric oxide.  

PubMed

Impact of manganese (Mn(2+)) excess (100, 500 and 1000 ?M over 7 days) on two ontogenetic stages (7-week-old plants and 7-day-old seedlings) of Matricaria chamomilla was compared. Mn excess depressed growth of seedlings (but not germination) and stimulated oxidative stress (ROS and lipid peroxidation) in both plants and seedlings. Growth inhibition could be evoked by higher Mn uptake and higher translocation factor in seedlings than in plants. Total thiols staining revealed elevation in almost all treatments. In 7-week-old plants, activity of peroxidases increased slightly and rather decreased under high Mn doses. Superoxide rather than hydrogen peroxide contributed to visualized ROS presence. Fluorescence of nitric oxide (NO) showed stimulation in plants but decrease in seedlings. Impact of exogenous nitric oxide donor (sodium nitroprusside/SNP) was therefore tested and results showed amelioration of 1000 ?M Mn-induced oxidative stress in seedlings (decrease in H2O2 and increase in NO content while antioxidative enzyme activities were variably affected) concomitantly with depleted Mn accumulation. It is concluded that NO participates in tolerance to Mn excess but negative effects of the highest SNP dose were also observed. Extensive fluorescence microscopy is also explanatively discussed. PMID:24388509

Ková?ik, Jozef; Babula, Petr; Hedbavny, Josef; Švec, Pavel

2014-02-01

306

Time-course of neuropathic pain in mice deficient in neuronal or inducible nitric oxide synthase.  

PubMed

Nitric oxide which is synthesised by nitric oxide synthase (NOS) is involved in processes related to regeneration after nerve injury and neuropathic pain. Here we investigated functional aspects of the nociceptive system. For that purpose, the chronic constriction injury (CCI) model induced by loose ligation of the sciatic nerve was employed in C57Bl/6J wild-type (WT), nNOS and iNOS knock-out (-/-) mice. Their thermal and mechanical pain thresholds were then measured over a period of six weeks. In addition, (3)H-DAMGO, (3)H-CP 55.940, and (3)H-l-glutamate binding, and neuronal (NeuN-immunostained) and astroglial (GFAP-immunostained) cell composition were studied. There were no significant differences in cell composition between the three strains used. Significant differences between CCI and sham-operated animals were found in nNOS-/- after day 6, in WT mice after day 10, and in iNOS-/- after day 17 post surgery. The mechanical pain threshold was normalised after day 45 post surgery in WT mice only. There were no changes in DAMGO and glutamate binding. However, we found significant differences in CP 55.940 binding in the spinal cord. It was concluded that NOS-cannabinoid interaction contributes to differences in nociceptive behaviour. PMID:24008126

Keilhoff, Gerburg; Schröder, Helmut; Peters, Brigitte; Becker, Axel

2013-12-01

307

Nitric oxide contributes to substance P-induced increases in lung rapidly adapting receptor activity in guinea-pigs.  

PubMed Central

1. Substance P induces fluid flux via nitric oxide, and fluid flux stimulates lung rapidly adapting receptors (RARs). We therefore proposed that nitric oxide contributes to substance P-evoked increases in RAR activity. Since substance P decreases dynamic compliance (Cdyn), which can stimulate RARs, we also determined whether nitric oxide contributed to substance P-induced effects on pulmonary function. 2. In anaesthetized guinea-pigs, the effects of substance P on RAR activity, Cdyn, pulmonary resistance (RL), and arterial blood pressure were measured before and after i.v. infusion of NG-methyl-L-arginine (L-NMMA; a nitric oxide synthase inhibitor), or L-NMMA followed by L-arginine (a nitric oxide precursor which reverses the effects of L-NMMA). 3. Substance P-evoked increases in RAR activity were blunted by L-NMMA (P = 0.006) but not by L-NMMA-L-arginine (P = 0.42). 4. Substance P-evoked decreases in Cdyn were slightly inhibited by L-NMMA (P = 0.02) and slightly enhanced by L-NMMA-L-arginine (P = 0.004). However, at the time at which L-NMMA maximally reduced substance P-induced RAR stimulation (the first 30 s), it did not change substance P-induced decreases in Cdyn. 5. Substance P-evoked increases in RL were not changed by L-NMMA (P = 0.10) and were enhanced by L-NMMA-L-arginine (P = 0.03). 6. L-NMMA-evoked increases in mean arterial blood pressure were reversed by L-arginine. Substance P-evoked decreases in mean arterial blood pressure were not changed by L-NMMA or by L-NMMA-L-arginine. 7. We conclude that nitric oxide contributes to substance P-evoked increases in RAR activity and that the increases are most probably independent of decreases in Cdyn. PMID:9379417

Joad, J P; Kott, K S; Bonham, A C

1997-01-01

308

Role of nitric oxide-induced mtDNA damage in mitochondrial dysfunction and apoptosis.  

PubMed

An increasing body of evidence suggests that nitric oxide (NO) can be cytotoxic and induce apoptosis. NO can also be genotoxic and cause DNA damage and mutations. It has been shown that NO damages mitochondrial DNA (mtDNA) to a greater extent than nuclear DNA. Previously, we reported that conditional targeting of the DNA repair protein hOGG1 into mitochondria using a mitochondria targeting sequence (MTS) augmented mtDNA repair of oxidative damage and enhanced cellular survival. To determine whether enhanced repair resulting from augmented expression of hOGG1 could also protect against the deleterious effects of NO, we used HeLa TetOff/MTS-OGG1-transfected cells to conditionally express hOGG1 in mitochondria. The effects of additional hOGG1 expression on repair of NO-induced mtDNA damage and cell survival were evaluated. These cells, along with vector transfectants, in either the presence or absence of doxycycline (Dox), were exposed to NO produced by the rapid decomposition of 1-propanamine, 3-(2-hydroxy-2-nitroso-1-propylhydrazino) (PAPA NONOate). Functional studies revealed that cells expressing recombinant hOGG1 were more proficient at repairing NO-induced mtDNA damage, which led to increased cellular survival following NO exposure. Moreover, the results described here show that conditional expression of hOGG1 in mitochondria decreases NO-induced inhibition of ATP production and protects cells from NO-induced apoptosis. PMID:16520228

Rachek, Lyudmila I; Grishko, Valentina I; Ledoux, Susan P; Wilson, Glenn L

2006-03-01

309

Emodin inhibits inducible nitric oxide synthase in a rat model of craniocerebral explosive injury.  

PubMed

To investigate the effects of emodin on blast-induced traumatic brain injury (bTBI) in a rat model. Eighty rats were randomly divided into 2 groups (the control group and the emodin-treated group; N = 40 per group) and were used to establish the model of blast-induced traumatic brain injury. Ten minutes after the explosion, an isotonic saline solution (10 mg/kg) or emodin (10 mg/kg) were administered via an intraperitoneal injection to the control group and the emodin-treated group, respectively. At each time point (pre-explosion, 2, 6, 12, 24 h after explosion), 2 rats were used for the pathological assessment and 6 rats were used for the biochemical assessment. The concentration of nitric oxide (NO) and the expression and activity of inducible nitric oxide synthase (iNOS) were measured at each time point by spectrophotometry and western blot analysis. Light and electron microscopy showed that the brain damage in the emodin-treated group was less serious than that observed in the control group. The concentration of NO in the emodin-treated group was lower compared with the control group (p < 0.05). Western blot analysis showed that protein expression in the emodin-treated group was lower than the control group (p < 0.05). Emodin can alleviate brain damage after bTBI by inhibiting iNOS. These findings suggest that emodin has a protective effect against bTBI. One possible mechanism may occur by inhibiting the expression and activity of iNOS and consequently decreasing the concentration of NO. PMID:25064046

Ma, Yuan; Xia, Xun; Cheng, Jing-min; Kuang, Yong-qin; Yang, Tao; Yang, Li-bin; Fan, Kexia; Gu, Jian-wen

2014-09-01

310

Nitric oxide protects the heart from ischemia-induced apoptosis and mitochondrial damage via protein kinase G mediated blockage of permeability transition and cytochrome c release  

E-print Network

Abstract Background Heart ischemia can rapidly induce apoptosis and mitochondrial dysfunction via mitochondrial permeability transition-induced cytochrome c release. We tested whether nitric oxide (NO) can block this damage in isolated rat heart...

Borutaite, Vilmante; Morkuniene, Ramune; Arandarcikaite, Odeta; Jekabsone, Aiste; Barauskaite, Jurgita; Brown, Guy C

2009-08-11

311

Synergy between ethanol and grape polyphenols, quercetin, and resveratrol, in the inhibition of the inducible nitric oxide synthase pathway  

Microsoft Academic Search

In atherosclerosis and tumor initiation, inducible nitric oxide synthase (iNOS) has been implicated in the damage of vascular walls and DNA, respectively. Moderate consumption of red wine has been ascribed as a preventive for coronary heart disease; however, there has been much debate over whether the beneficial effect is from grape polyphenolic components or ethanol. We studied the interaction of

Marion Man-Ying Chan; John A Mattiacci; Hyon S Hwang; Amit Shah; Dunne Fong

2000-01-01

312

Effects of interleukin-1? on vascular reactivity after lipopolysaccharide-induced endotoxic shock in rabbits and its relationship with PKC and Rho kinase.  

PubMed

Calcium desensitization plays a critical role in the occurrence of vascular hyporeactivity after shock. Interleukin (IL)-1? participates in the regulation of vascular reactivity via both nitric oxide (NO)-dependent and NO-independent mechanisms. However, the specific NO-independent pathway remains to be established. The issue of whether IL-1? modulates vascular reactivity via regulation of calcium sensitivity in the NO-independent mechanism is unclear. In the current study, effects of IL-1? on vascular calcium sensitivity and its relationship with PKC and Rho kinase were investigated in vivo and in vitro using a rabbit model of lipopolysaccharide (LPS)-induced endotoxic shock and superior mesenteric arteries (SMAs), respectively. The calcium sensitivity profile of SMAs displayed a biphasic change after LPS-induced endotoxic shock (significant increase at 0.5 hour and 1 hour after LPS administration and marked decrease after 2 hours) and was negatively related to changes in serum IL-1?. The IL-1 receptor antagonist, IL-1ra (4 ?g/mL), partly reversed LPS-induced calcium desensitization. In vitro incubation with IL-1? (50-200 ng/mL) reduced the calcium sensitivity of SMAs and suppressed the activities of Rho kinase and PKC and the phosphorylation of 20-kDa myosin light chain. These effects of IL-1? were shown to be regulated by the PKC agonist, phorbol 12-myristate 13-acetate, and Rho kinase agonist and antagonist, angiotensin II, and Y-27632, respectively. Our results collectively suggest that IL-1? participates in vascular hyporeactivity after endotoxic shock via regulation of vascular calcium sensitivity. Moreover, this regulatory effect of IL-1? seems closely related to downregulation of the activities of PKC and Rho kinase. PMID:23846803

Liang, Jia-lin; Yang, Guang-ming; Li, Tao; Liu, Liang-ming

2013-07-01

313

Visualizing inducible nitric-oxide synthase in living cells with a heme-binding fluorescent inhibitor.  

PubMed

The study of nitric-oxide synthase (NOS) physiology is constrained by the lack of suitable probes to detect NOS in living cells or animals. Here, we characterized a fluorescent inducible NOS (iNOS) inhibitor called PIF (pyrimidine imidazole FITC) and examined its utility for microscopic imaging of iNOS in living cells. PIF binding to iNOS displayed high affinity, isoform selectivity, and heme specificity, and was essentially irreversible. PIF was used to successfully image iNOS expressed in RAW264.7 cells, HEK293T cells, human A549 epithelial cells, and freshly obtained human lung epithelium. PIF was used to estimate a half-life for iNOS of 1.8 h in HEK293T cells. Our work reveals that fluorescent probes like PIF will be valuable for studying iNOS cell biology and in understanding the pathophysiology of diseases that involve dysfunctional iNOS expression. PMID:16006534

Panda, Koustubh; Chawla-Sarkar, Mamta; Santos, Cecile; Koeck, Thomas; Erzurum, Serpil C; Parkinson, John F; Stuehr, Dennis J

2005-07-19

314

A Model of Nitric Oxide Induced ?-Synuclein Misfolding in Parkinson's Disease  

PubMed Central

Inducible nitric oxide synthase (iNOS) upregulation and consequent NO formation are well-recognized neuroinflammatory responses associated with Parkinson’s disease (PD). These contribute to nitrosative protein modifications affecting neuronal injury and cell death. Indeed, a pathobiologic signature for PD is Lewy body formation containing misfolded and aggregated forms of alpha-synuclein (?-syn). Moreover, nitration of ?-syn promotes protein aggregation in disease. To model such pathological events, we constructed controllable iNOS and bicistronic ?-syn-IRES-tTA adeno-associated virus (AAV) expression vectors. Transduction of iNOS and ?-syn AAV constructs led to nitration of ?-syn in neurons and overexpression of iNOS promoted protein aggregation. We posit that this AAV system mimics critical protein misfolding events associated with the pathogenesis of PD. PMID:22776646

Stone, David K.; Kiyota, Tomomi; Mosley, R. Lee; Gendelman, Howard E.

2012-01-01

315

Lysophosphatidic acid induces vasodilation mediated by LPA1 receptors, phospholipase C, and endothelial nitric oxide synthase.  

PubMed

Lysophosphatidic acid (LPA) has been implicated as a mediator of several cardiovascular functions, but its potential involvement in the control of vascular tone is obscure. Here, we show that both LPA (18:1) and VPC31143 (a synthetic agonist of LPA1-3 receptors) relax intact mouse thoracic aorta with similar Emax values (53.9 and 51.9% of phenylephrine-induced precontraction), although the EC50 of LPA- and VPC31143-induced vasorelaxations were different (400 vs. 15 nM, respectively). Mechanical removal of the endothelium or genetic deletion of endothelial nitric oxide synthase (eNOS) not only diminished vasorelaxation by LPA or VPC31143 but converted it to vasoconstriction. Freshly isolated mouse aortic endothelial cells expressed LPA1, LPA2, LPA4 and LPA5 transcripts. The LPA1,3 antagonist Ki16425, the LPA1 antagonist AM095, and the genetic deletion of LPA1, but not that of LPA2, abolished LPA-induced vasorelaxation. Inhibition of the phosphoinositide 3 kinase-protein kinase B/Akt pathway by wortmannin or MK-2206 failed to influence the effect of LPA. However, pharmacological inhibition of phospholipase C (PLC) by U73122 or edelfosine, but not genetic deletion of PLC?, abolished LPA-induced vasorelaxation and indicated that a PLC enzyme, other than PLC?, mediates the response. In summary, the present study identifies LPA as an endothelium-dependent vasodilator substance acting via LPA1, PLC, and eNOS. PMID:24249637

Ruisanchez, Éva; Dancs, Péter; Kerék, Margit; Németh, Tamás; Faragó, Bernadett; Balogh, Andrea; Patil, Renukadevi; Jennings, Brett L; Liliom, Károly; Malik, Kafait U; Smrcka, Alan V; Tigyi, Gabor; Benyó, Zoltán

2014-02-01

316

Nitric oxide alleviates heat stress-induced oxidative damage in Pleurotus eryngii var. tuoliensis.  

PubMed

High temperature is one of the major impediments limiting the growth and development of most edible fungi. While many efforts have been made in agricultural practice, the mechanism for resistance to high temperature remains elusive. Nitric oxide (NO) is considered as a signaling molecule involved in regulation of diverse physiological processes and stress responses in animals and plants. However, the role of NO in regulating fungal, particularly edible fungi, response to abiotic stresses, is unknown. The present study demonstrated that NO could effectively alleviate oxidative damage induced by heat stress in mycelia of Pleurotus eryngii var. tuoliensis. Heat stress induced increased thiobarbituric acid reactive substance (TBARS) content in mycelia, and the NO donor sodium nitroprusside (SNP) dramatically decreased TBARS content under high temperature. Moreover, the specific NO scavenger, 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-1-oxyl-3-oxide (cPTIO), could arrest the SNP action under the stress. Heat stress induced an increase in endogenous NO production in mycelial cells. However, the effect was significantly blocked by the NO synthase (NOS) inhibitor l-N(G)-nitroarginine methyl ester (l-NAME). In contrast, nitrate reductase (NR) activities were not obviously altered during heat stress. The NR suppressor tungstate had no effect on intracellular NO abundance under heat stress. These results suggest that NO can effectively protect mycelia of edible fungi from heat stress-induced oxidative damage and the NOS-dependent NO production may participate in the response to heat stress. PMID:22202810

Kong, Weiwei; Huang, Chenyang; Chen, Qiang; Zou, Yajie; Zhang, Jinxia

2012-01-01

317

Contribution of radiation-induced, nitric oxide-mediated bystander effect to radiation-induced adaptive response.  

NASA Astrophysics Data System (ADS)

There has been a recent upsurge of interest in radiation-induced adaptive response and bystander effect which are specific modes in stress response to low-dose low-dose rate radiation Recently we found that the accumulation of inducible nitric oxide NO synthase iNOS in wt p53 cells was induced by chronic irradiation with gamma rays followed by acute irradiation with X-rays but not by each one resulting in an increase in nitrite concentrations of medium It is suggested that the accumulation of iNOS may be due to the depression of acute irradiation-induced p53 functions by pre-chronic irradiation In addition we found that the radiosensitivity of wt p53 cells against acute irradiation with X-rays was reduced after chronic irradiation with gamma rays This reduction of radiosensitivity of wt p53 cells was nearly completely suppressed by the addition of NO scavenger carboxy-PTIO to the medium This reduction of radiosensitivity of wt p53 cells is just radiation-induced adaptive response suggesting that NO-mediated bystander effect may considerably contribute to adaptive response induced by radiation

Matsumoto, H.; Ohnishi, T.

318

Iron induces protection and necrosis in cultured cardiomyocytes: Role of reactive oxygen species and nitric oxide.  

PubMed

We investigate here the role of reactive oxygen species and nitric oxide in iron-induced cardiomyocyte hypertrophy or cell death. Cultured rat cardiomyocytes incubated with 20 microM iron (added as FeCl(3)-Na nitrilotriacetate, Fe-NTA) displayed hypertrophy features that included increased protein synthesis and cell size, plus realignment of F-actin filaments along with sarcomeres and activation of the atrial natriuretic factor gene promoter. Incubation with higher Fe-NTA concentrations (100 microM) produced cardiomyocyte death by necrosis. Incubation for 24 h with Fe-NTA (20-40 microM) or the nitric oxide donor Delta-nonoate increased iNOS mRNA but decreased iNOS protein levels; under these conditions, iron stimulated the activity and the dimerization of iNOS. Fe-NTA (20 microM) promoted short- and long-term generation of reactive oxygen species, whereas preincubation with l-arginine suppressed this response. Preincubation with 20 microM Fe-NTA also attenuated the necrotic cell death triggered by 100 microM Fe-NTA, suggesting that these preincubation conditions have cardioprotective effects. Inhibition of iNOS activity with 1400 W enhanced iron-induced ROS generation and prevented both iron-dependent cardiomyocyte hypertrophy and cardioprotection. In conclusion, we propose that Fe-NTA (20 microM) stimulates iNOS activity and that the enhanced NO production, by promoting hypertrophy and enhancing survival mechanisms through ROS reduction, is beneficial to cardiomyocytes. At higher concentrations, however, iron triggers cardiomyocyte death by necrosis. PMID:19969068

Munoz, Juan Pablo; Chiong, Mario; García, Lorena; Troncoso, Rodrigo; Toro, Barbra; Pedrozo, Zully; Diaz-Elizondo, Jessica; Salas, Daniela; Parra, Valentina; Núñez, Marco T; Hidalgo, Cecilia; Lavandero, Sergio

2010-02-15

319

tBHQ inhibits LPS-induced microglial activation via Nrf2-mediated suppression of p38 phosphorylation  

Microsoft Academic Search

Role of microglial Nrf2 activation in preventing neuronal death caused by microglial hyperactivation is investigated by using BV-2 microglial cells as modulator and primary neurons as target. Pretreatment of microglial cells with tBHQ, a phenolic antioxidant activating Nrf2, attenuated the LPS-derived overproduction of pro-inflammatory neurotoxic mediators like TNF-?, IL-1?, IL-6, PGE2, and NO as well as the morphological changes associated

Kyungmi Koh; Youngnam Cha; Sunyoung Kim; Jiyoung Kim

2009-01-01

320

Abies koreana Essential Oil Inhibits Drug-Resistant Skin Pathogen Growth and LPS-Induced Inflammatory Effects of Murine Macrophage  

Microsoft Academic Search

Since acne vulgaris is the combined result of a bacterial infection and the inflammatory response to that infection, we examined\\u000a whether Abies koreana essential oil (AKE) possessed anti-inflammatory and antibacterial activities against skin pathogens. In this study, AKE showed\\u000a excellent antibacterial activities against drug-susceptible and -resistant Propionibacterium acnes and Staphylococcus epidermidis, which are acne-causing bacteria. In addition, AKE reduced the

Weon-Jong Yoon; Sang-Suk Kim; Tae-Heon Oh; Nam Ho Lee; Chang-Gu Hyun

2009-01-01

321

LPS-Induced Inflammation Potentiates the IL-1?-Mediated Reduction of LH Secretion from the Anterior Pituitary Explants  

PubMed Central

Acting at the level of the brain, interleukin- (IL-)1? is considered to be one of the most potent downregulators of reproduction processes during immune/inflammatory challenge. IL-1? suppresses gonadotropin-releasing hormone (GnRH) secretion from the hypothalamus resulting in the inhibition of the luteinizing hormone (LH) release from the anterior pituitary (AP). However, the presence of IL-1? receptors in the AP suggests the possible direct action of this cytokine on LH secretion. The study was designed to determine the effect of IL-1? on the LH secretion from the AP explants collected from saline and LPS-treated ewes in the follicular phase. It was found that IL-1? suppressed (P ? 0.01) GnRH-stimulated LH release and LH? gene expression in AP explants in both groups. However, IL-1? action was more potent in the explants collected from LPS-treated animals. Pituitaries from LPS-treated animals were characterized by increased (P ? 0.01) IL-1 type I receptor and decreased (P ? 0.01) GnRH receptor gene expression level compared to the saline-treated group. IL-1? also affected the GnRH-R gene expression in explants collected from LPS-treated animals. Our results show that direct action of IL-1? on the pituitary gonadotropes could be one of the reasons of the reproductive processes disorders accompanying an inflammatory state. PMID:23956762

Herman, Andrzej Przemyslaw; Dobek, Elzbieta

2013-01-01

322

LPS-induced inflammation potentiates the IL-1?-mediated reduction of LH secretion from the anterior pituitary explants.  

PubMed

Acting at the level of the brain, interleukin- (IL-)1 ? is considered to be one of the most potent downregulators of reproduction processes during immune/inflammatory challenge. IL-1 ? suppresses gonadotropin-releasing hormone (GnRH) secretion from the hypothalamus resulting in the inhibition of the luteinizing hormone (LH) release from the anterior pituitary (AP). However, the presence of IL-1 ? receptors in the AP suggests the possible direct action of this cytokine on LH secretion. The study was designed to determine the effect of IL-1 ? on the LH secretion from the AP explants collected from saline and LPS-treated ewes in the follicular phase. It was found that IL-1 ? suppressed (P ? 0.01) GnRH-stimulated LH release and LH ? gene expression in AP explants in both groups. However, IL-1 ? action was more potent in the explants collected from LPS-treated animals. Pituitaries from LPS-treated animals were characterized by increased (P ? 0.01) IL-1 type I receptor and decreased (P ? 0.01) GnRH receptor gene expression level compared to the saline-treated group. IL-1 ? also affected the GnRH-R gene expression in explants collected from LPS-treated animals. Our results show that direct action of IL-1 ? on the pituitary gonadotropes could be one of the reasons of the reproductive processes disorders accompanying an inflammatory state. PMID:23956762

Herman, Andrzej Przemys?aw; Krawczy?ska, Agata; Bochenek, Joanna; Dobek, El?bieta; Herman, Anna; Tomaszewska-Zaremba, Dorota

2013-01-01

323

Protection against LPS-induced cartilage inflammation and degradation provided by a biological extract of Mentha spicata  

Microsoft Academic Search

BACKGROUND: A variety of mint [Mentha spicata] has been bred which over-expresses Rosmarinic acid (RA) by approximately 20-fold. RA has demonstrated significant anti-inflammatory activity in vitro and in small rodents; thus it was hypothesized that this plant would demonstrate significant anti-inflammatory activity in vitro. The objectives of this study were: a) to develop an in vitro extraction procedure which mimics

Wendy Pearson; Ronald S Fletcher; Laima S Kott; Mark B Hurtig

2010-01-01

324

Lack of TCRalphabeta+ CD8+ and TCRgammadelta+ lymphocytes ameliorates LPS induced orchitis in mice--preliminary histological observations.  

PubMed

The inflammation of the reproductive system can affect reproduction causing partial or complete infertility. It is well known that lipopolysaccharide (LPS) triggers an inflammatory response in the whole organism, including immunologically privileged organs, e.g. the testicles. Adult male TCRalpha-/-, TCRdelta-/-, CD1d-/- and beta2m-/- on B10.PL (H-2(u)) and B10.PL control mice were intraperitonealy (i.p.) injected with lipopolysaccharide (LPS). The animals were killed 24h and 10 days post LPS treatment and their gonads were prepared for microscopic examination. Histological changes in the testes after LPS injection were found only in control B10PL and CD1d-/- mice. The experiments revealed disturbances in Leydig's glands structure, blood vessel dilatation in the interstitial tissue as well as degeneration of seminal tubule epithelium, disruption ofspermatogenesis and subsequent decrease of sperm cell number in the tubule lumen. These changes were noticed mainly 10 days after LPS treatment. Lack of either TCRalphabeta+ CD8+ or TCRgammadelta+ lymphocytes diminishes the response of testicular macrophages to LPS whereas the absence of CD1d-dependent NKT cells does not affect macrophage reactivity. PMID:24745151

Sliwa, Leopold; Macura, Barbara; Majewska-Szczepanik, Monika; Szczepanik, Marian

2014-01-01

325

C-glycosylflavones from the aerial parts of Eleusine indica inhibit LPS-induced mouse lung inflammation.  

PubMed

The infusion of aerial parts (EI) of Eleusine indica Gaertn (Poaceae) is used in Brazil against airway inflammatory processes like influenza and pneumonia. Pre-treatment with 400 mg/kg of crude extract inhibited 98% of lung neutrophil recruitment in mice exposed to aerosols of lipopolysaccharide (LPS) from Gram-negative bacteria, in a dose-dependent manner. At 400 microg/kg, schaftoside (6-C-beta-glucopyranosyl-8-C-alpha-arabinopyranosylapigenin) and vitexin (8-C-beta-glucopyranosylapigenin), isolated from EI, inhibited 62% and 80% of lung neutrophil influx, respectively. These results may justify the popular use of E. indica against airway inflammatory processes. PMID:15856415

De Melo, Giany O; Muzitano, Michelle F; Legora-Machado, Alexandre; Almeida, Thais A; De Oliveira, Daniela B; Kaiser, Carlos R; Koatz, Vera Lucia G; Costa, Sônia S

2005-04-01

326

IL6 induces PI 3-kinase and nitric oxide-dependent protection and preserves mitochondrial function in cardiomyocytes  

Microsoft Academic Search

Objective: Interleukin-6 (IL-6) is a pro-inflammatory cytokine which is a prognostic marker associated with left ventricular contractile dysfunction and heart failure. On the other hand, IL-6 activates signalling pathways which mediate delayed ischemic preconditioning. We have therefore studied the cellular mechanisms of IL-6-induced cardioprotection. Methods: Inducible nitric oxide synthase (iNOS) expression, cardiomyocyte calcium handling, mitochondrial energetics, and the activation of

Nicola Smart; Mart H. Mojet; David S. Latchman; Michael S. Marber; Michael R. Duchen; Richard J. Heads

2006-01-01

327

Nitric Oxide Regulates Cell Sensitivity to Cisplatin-Induced Apoptosis through S-Nitrosylation and Inhibition of Bcl2 Ubiquitination  

Microsoft Academic Search

Cisplatin is a potent cytotoxic agent commonly used for the treatment of solid tumors. However, tumor cell-acquired resistance to cisplatin-induced apoptosis is a major limitation for efficient therapy, as frequently observed in human lung cancer. Nitric oxide (NO) is a key regulator of apoptosis, but its role in cisplatin-induced cell death and the underlying mechanism are largely unknown. Previous studies

Ubonthip Nimmannit; Christian Stehlik; Liying Wang; Bing-Hua Jiang; Boonsri Ongpipatanakul; Yon Rojanasakul

2006-01-01

328

Entada africana fraction CH2Cl2/MEOH 5% inhibits inducible nitric oxide synthase and pro-inflammatory cytokines gene expression induced by lipopolysaccharide in microglia  

PubMed Central

Background Inflammatory response in the CNS mediated by microglia cells play an important role in host defense and is implicated in the pathology of neurodegenerative diseases. We investigated the capacity of Entada africana to protect microglia from inflammatory insults by exploring the effect of the CH2Cl2/MEOH 5% fraction (Ea5) on pro-inflammatory cytokines mRNA expression. Finally, we studied the effect of Ea5 on the inhibition of p38 MAPK Kinase. The results were compared to those obtained with Baicalin, a well reported anti-inflammatory flavonoid. Methods Barks from E. africana were harvested in 2010, in the west region of Cameroon. A crude extract was prepared using CH2Cl2/MEOH 1:1 V/V. The crude extract obtained was further fractionated by flash chromatography. A mouse microglia cell line (N9) was stimulated by LPS with or without different concentrations of Baicalin and Ea5. The release of NO was evaluated using the Griess method. The expression of pro-inflammatory cytokines mRNA (TNF?, IL-1?, IL-6) and iNOS/NO were measured by RT- PCR. The inhibition of p38 MAPK Kinase was assessed using ELISA. Results We found that Ea5, as well as Baicalin inhibited LPS-induced NO production in a dose dependent manner. Ea5 was most active in term of NO inhibition (87.07%), in comparison to Baicalin (70.85%). The expression of TNF?, IL-1?, IL-6 and iNOS was strongly suppressed by Ea5 in microglia. Ea5 also inhibited the activity of p38MAPK Kinase, up to 30% for the concentrations tested, whereas a prominent inhibition was obtained with Baicalin. Conclusion These results suggest that E. africana may contain promising compounds useful for the treatment of diseases cause by over-activation of microglia such as Alzheimer disease and other neurological diseases. PMID:24089706

2013-01-01

329

The Arabidopsis Prohibitin Gene PHB3 Functions in Nitric Oxide-Mediated Responses and in Hydrogen Peroxide-Induced Nitric Oxide Accumulation[C][W  

PubMed Central

To discover genes involved in nitric oxide (NO) metabolism, a genetic screen was employed to identify mutants defective in NO accumulation after treatment with the physiological inducer hydrogen peroxide. In wild-type Arabidopsis thaliana plants, NO levels increase eightfold in roots after H2O2 treatment for 30 min. A mutant defective in H2O2-induced NO accumulation was identified, and the corresponding mutation was mapped to the prohibitin gene PHB3, converting the highly conserved Gly-37 to an Asp in the protein's SPFH domain. This point mutant and a T-DNA insertion mutant were examined for other NO-related phenotypes. Both mutants were defective in abscisic acid–induced NO accumulation and stomatal closure and in auxin-induced lateral root formation. Both mutants were less sensitive to salt stress, showing no increase in NO accumulation and less inhibition of primary root growth in response to NaCl treatment. In addition, light-induced NO accumulation was dramatically reduced in cotyledons. We found no evidence for impaired H2O2 metabolism or signaling in the mutants as H2O2 levels and H2O2-induced gene expression were unaffected by the mutations. These findings identify a component of the NO homeostasis system in plants and expand the function of prohibitin genes to include regulation of NO accumulation and NO-mediated responses. PMID:20068191

Wang, Yong; Ries, Amber; Wu, Kati; Yang, Albert; Crawford, Nigel M.

2010-01-01

330

Hypoxia augments lipopolysaccharide-induced cytokine expression in periodontal ligament cells.  

PubMed

Periodontitis is a chronic inflammatory disease characterized by the destruction of tooth supporting tissues. Hypoxia, the mainly changes of the plateau environment, can induce severe periodontitis by animal experiments. There is, however, very little information on hypoxia and lipopolysaccharide (LPS) induced cytokine expression in periodontal ligament (PDL) cells. In this article, we characterized hypoxia or P. gingivalis lipopolysaccharide (Pg LPS) induced tumor necrosis factor alpha (TNF-?), interleukin (IL)-1?, and IL-6 expression by human periodontal ligament (hPDL) cells. We found that hypoxia augmented Pg LPS induced TNF-?, IL-1?, and IL-6 expression in hPDL cells. We also demonstrated that nuclear factor kappa B pathway was involved in hypoxia augmenting Pg LPS induced cytokine expression in hPDL cells. Thus, our results suggest that the hypoxic environment may enhance the immune function of hPDL cells that is induced by Pg LPS. PMID:24609838

Jian, Congxiang; Li, Chenjun; Ren, Yu; He, Yong; Li, Yunming; Feng, Xiaodan; Zhang, Gang; Tan, Yinghui

2014-10-01

331

Interferon-?-Induced Nitric Oxide Causes Intrinsic Intestinal Denervation in Trypanosoma cruzi-Infected Mice  

PubMed Central

In this study, the role of nitric oxide (NO) in neuronal destruction during acute-phase Trypanosoma cruzi infection was evaluated in male C57BL/6 (WT, wild-type) mice and knockout mice [inducible nitric oxide synthase (iNOS)?/? and interferon (IFN)?/?]. Selected animals were infected by intraperitoneal injection of 100 trypomastigote forms of the Y strain of T. cruzi. Others were injected intraperitoneally with an equal volume of saline solution and served as controls. Our findings support those of previous studies regarding myenteric denervation in acute-phase T. cruzi infection. In addition, we clearly demonstrate that, despite the fact that parasite nests and similar inflammatory infiltrate in the intestinal wall were more pronounced in infected iNOS?/? mice than in infected WT mice, the former presented no reduction in myenteric plexus neuron numbers. Neuronal nerve profile expression, as revealed by the general nerve marker PGP 9.5, was preserved in all knockout animals. Infected IFN?/? mice suffered no significant neuronal loss and there was no inflammatory infiltrate in the intestinal wall. On days 5 and 10 after infection, iNOS activity was greater in infected WT mice than in controls, whereas iNOS activity in infected knockout mice remained unchanged. These findings clearly demonstrate that neuronal damage does not occur in NO-impaired infected knockout mice, regardless of whether inflammatory infiltrate is present (iNOS?/?) or absent (IFN?/?). In conclusion, our observations strongly indicate that myenteric denervation in acute-phase T. cruzi infection is because of IFN-?-elicited NO production resulting from iNOS activation in the inflammatory foci along the intestinal wall. PMID:15039223

Arantes, Rosa M.E.; Marche, Homero H.F.; Bahia, Maria T.; Cunha, Fernando Q.; Rossi, Marcos A.; Silva, Joao S.

2004-01-01

332

Nitric Oxide Synthase Promotes Distension-Induced Tracheal Venular Leukocyte Adherence  

PubMed Central

The process of leukocyte recruitment to the airways in real time has not been extensively studied, yet airway inflammation persists as a major contributor to lung pathology. We showed previously in vivo, that neutrophils are recruited acutely to the large airways after periods of airway distension imposed by the application of positive end-expiratory pressure (PEEP). Given extensive literature implicating products of nitric oxide synthase (NOS) in lung injury after ventilatory over-distension, we questioned whether similar mechanisms exist in airway post-capillary venules. Yet, endothelial nitric oxide has been shown to be largely anti-inflammatory in other systemic venules. Using intravital microscopy to visualize post-capillary tracheal venules in anesthetized, ventilated mice, the number of adherent leukocytes was significantly decreased in eNOS-/- mice under baseline conditions (2±1 cell/60 min observation) vs wild type (WT) C57BL/6 mice (7±2 cells). After exposure to PEEP (8 cmH2O for 1 min; 5 times), adherent cells increased significantly (29±5 cells) in WT mice while eNOS-/- mice demonstrated a significantly decreased number of adherent cells (11±4 cells) after PEEP. A similar response was seen when thrombin was used as the pro-inflammatory stimulus. In addition, mouse tracheal venular endothelial cells studied in vitro after exposure to cyclic stretch (18% elongation) or thrombin both demonstrated increased p-selectin expression that was significantly attenuated by NG-nitro-L-arginine methyl ester, N-acetylcysteine amide (NACA) and excess BH4. In vivo treatment with the ROS inhibitor NACA or co-factor BH4 abolished completely the PEEP-induced leukocyte adherence. These results suggest that pro-inflammatory stimuli cause leukocyte recruitment to tracheal endothelium in part due to eNOS uncoupling. PMID:25181540

Moldobaeva, Aigul; Rentsendorj, Otgonchimeg; Jenkins, John; Wagner, Elizabeth M.

2014-01-01

333

Nitric oxide exerts protective effects against bleomycin-induced pulmonary fibrosis in mice  

PubMed Central

Background Increased expression of nitric oxide synthase (NOS) and an increase in plasma nitrite plus nitrate (NOx) have been reported in patients with pulmonary fibrosis, suggesting that nitric oxide (NO) plays an important role in its development. However, the roles of the entire NO and NOS system in the pathogenesis of pulmonary fibrosis still remain to be fully elucidated. The aim of the present study is to clarify the roles of NO and the NOS system in pulmonary fibrosis by using the mice lacking all three NOS isoforms. Methods Wild-type, single NOS knockout and triple NOS knockout (n/i/eNOS?/?) mice were administered bleomycin (BLM) intraperitoneally at a dose of 8.0 mg/kg/day for 10 consecutive days. Two weeks after the end of the procedure, the fibrotic and inflammatory changes of the lung were evaluated. In addition, we evaluated the effects of long-term treatment with isosorbide dinitrate, a NO donor, on the n/i/eNOS?/? mice with BLM-induced pulmonary fibrosis. Results The histopathological findings, collagen content and the total cell number in bronchoalveolar lavage fluid were the most severe/highest in the n/i/eNOS?/? mice. Long-term treatment with the supplemental NO donor in n/i/eNOS?/? mice significantly prevented the progression of the histopathological findings and the increase of the collagen content in the lungs. Conclusions These results provide the first direct evidence that a lack of all three NOS isoforms led to a deterioration of pulmonary fibrosis in a BLM-treated murine model. We speculate that the entire endogenous NO and NOS system plays an important protective role in the pathogenesis of pulmonary fibrosis. PMID:25092105

2014-01-01

334

Relaxin Counteracts Myocardial Damage Induced by Ischemia-Reperfusion in Isolated Guinea Pig Hearts: Evidence for an Involvement of Nitric Oxide  

Microsoft Academic Search

Relaxin was previously shown to cause coronary vasodilation and to inhibit mast cell activation through a stimulation of endogenous nitric oxide production. This suggests that relaxin may have benefi- cial effects on ischemia-reperfusion-induced myocardial injury, which is triggered by endothelial damage and impaired nitric oxide gener- ation. In this study, we tested the effect of relaxin on isolated and perfused

EMANUELA MASINI; DANIELE BANI; MARIA GRAZIA BELLO; MARIO BIGAZZI; PIER FRANCESCO MANNAIONI; TATIANA BANI SACCHI

1997-01-01

335

Inhibition of inducible nitric oxide synthase prevents lipid peroxidation in osteoarthritic chondrocytes.  

PubMed

Nitric oxide (NO) and the lipid peroxidation (LPO) product 4-hydroxynonenal (HNE) are considered to be key mediators of cartilage destruction in osteoarthritis (OA). NO is also known to be an important intermediary in LPO initiation through peroxynitrite formation. The aim of the present study was to assess the ability of the inducible NO synthase (iNOS) inhibitor N-iminoethyl-L-lysine (L-NIL) to prevent HNE generation via NO suppression in human OA chondrocytes and cartilage explants. Human OA chondrocytes and cartilage explants were treated with L-NIL and thereafter with or without interleukin-1beta (IL-1?) or HNE at cytotoxic or non-cytotoxic concentrations. Parameters related to oxidative stress, apoptosis, inflammation, and catabolism were investigated. L-NIL stifled IL-1?-induced NO release, iNOS activity, nitrated proteins, and HNE generation in a dose-dependent manner. It also blocked IL-1?-induced inactivation of the HNE-metabolizing glutathione-s-transferase (GST). L-NIL restored both HNE and GSTA4-4 levels in OA cartilage explants. Interestingly, it also abolished IL-1?-evoked reactive oxygen species (ROS) generation and p47 NADPH oxidase activation. Furthermore, L-NIL significantly attenuated cell death and markers of apoptosis elicited by exposure to a cytotoxic dose of HNE as well as the release of prostaglandin E(2) and metalloproteinase-13 induced by a non-cytotoxic dose of HNE. Altogether, our findings support a beneficial effect of L-NIL in OA by (i) preventing the LPO process and ROS production via NO-dependent and/or independent mechanisms and (ii) attenuating HNE-induced cell death and different mediators of cartilage damage. PMID:22573548

Bentz, Mireille; Zaouter, Charlotte; Shi, Qin; Fahmi, Hassan; Moldovan, Florina; Fernandes, Julio C; Benderdour, Mohamed

2012-07-01

336

Oenothera laciniata inhibits lipopolysaccharide induced production of nitric oxide, prostaglandin E2, and proinflammatory cytokines in RAW264.7 macrophages.  

PubMed

We elucidated the pharmacological and biological effects of Oenothera laciniata extracts on the production of inflammatory mediators in macrophages. The CH(2)Cl(2) fraction of O. laciniata extract effectively inhibited LPS-induced NO, PGE(2), and proinflammatory cytokine production in RAW264.7 cells. These inhibitory effects of the CH(2)Cl(2) fraction of O. laciniata were accompanied by decreases in the expression of iNOS and COX-2 proteins and iNOS, COX-2, TNF-alpha, IL-1beta, and IL-6 mRNA. Asiatic acid and quercetin were present in the HPLC fingerprint of the O. laciniata extract. We tested the potential application of O. laciniata extract as a cosmetic material by performing primary skin irritation tests. In New Zealand white rabbits, primary irritation tests revealed that application of O. laciniata extracts (1%) did not induce erythema or edema formation. Human skin primary irritation tests were performed on the normal skin (upper back) of 30 volunteers to determine if any material in O. laciniata extracts had irritation or sensitization potential. In these assays, O. laciniata extracts did not induce any adverse reactions. Based on these results, we suggest that O. laciniata extracts be considered possible anti-inflammatory candidates for topical application. PMID:19332304

Yoon, Weon-Jong; Ham, Young Min; Yoo, Byoung-Sam; Moon, Ji-Young; Koh, Jaesook; Hyun, Chang-Gu

2009-04-01

337

Colorectal carcinoma development in inducible nitric oxide synthase-deficient mice with dextran sulfate sodium-induced ulcerative colitis.  

PubMed

The overproduction of reactive oxygen and nitrogen species (RONS) may play an important role in ulcerative colitis (UC)-associated carcinogenesis. In order to study the role of nitric oxide (NO) in UC-associated colorectal carcinogenesis, the development of colorectal carcinoma was studied using the DSS-induced and iron-enhanced model of chronic UC in inducible nitric oxide synthase (iNOS)-deficient mice. Female wild-type C57BL/6 (iNOS+/+) and iNOS-/- mice were administered 1% DSS (w/v) through the drinking fluid for 15 DSS cycles and fed twofold iron-enriched diet. Colorectal inflammation and mucosal ulceration of moderate severity were observed in both iNOS+/+ and iNOS-/- mice. Similar tumor incidence and multiplicity in the colon were observed that 15 out of 23 (65.2%) iNOS+/+ mice developed colorectal tumors with a tumor multiplicity of 1.47+/-0.17 (mean+/-SE) after 15 DSS cycles, and 13 out of 19 (68.4%) iNOS-/- mice developed colorectal tumors with a tumor multiplicity of 2.08+/-0.21. Histopathologically, the tumors were confirmed to be well-differentiated adenocarcinomas. Nitrotyrosine, an indicator of peroxynitrite-caused protein modification, was detectable by immunohistochemistry in inflammatory cells and epithelial cells of the colon in iNOS+/+ and iNOS-/- mice, and no difference in staining intensity was observed between the two groups. Immunostaining for endothelial NOS (eNOS) was observed in lamina propria macrophages and colonic blood vessels, and eNOS protein levels were increased in the inflamed colon. These results show that there is no difference in UC-associated cancer development in iNOS+/+ and iNOS-/- mice, and suggest that in the absence of iNOS, other factors, such as eNOS, may play a role in nitrosative stress and UC-associated carcinogenesis in this model system. PMID:17219424

Seril, Darren N; Liao, Jie; Yang, Guang-Yu

2007-05-01

338

Chrysoeriol potently inhibits the induction of nitric oxide synthase by blocking AP-1 activation.  

PubMed

Chrysoeriol is a flavonoid with antioxidant and anti-inflammatory activities. Despite the large number of studies performed on its biological activities, no clear picture of its mode of action has emerged. In the present study, we isolated chrysoeriol from the leaves of Digitalis purpurea (foxglove), and studied its effect on the induction of the inducible nitric oxide synthase (iNOS) gene, and the mechanism of this induction in Raw264.7 macrophages. Chrysoeriol pretreatment potently inhibited the release of NO in the cells treated with lipopolysaccharide (LPS), and Western blot and RT-PCR analyses revealed that chrysoeriol inhibited the LPS-induced inductions of iNOS gene. Moreover, it is known that the activations of nuclear factor-kappaB (NF-kappaB) and activator protein 1 (AP-1) are crucial steps in the transcriptional activation of the iNOS gene. Here, we found that chrysoeriol selectively suppressed AP-1 activation, and that activation of AP-1 is likely to be essential for iNOS induction in LPS-treated macrophages. This presumed inhibitory effect on AP-1 activation by chrysoeriol may be associated with its potent NO blocking and anti-inflammatory effects. PMID:16228289

Choi, Doo-Youn; Lee, Jeong Yong; Kim, Mi-Ran; Woo, Eun-Rhan; Kim, Yoon Gyoon; Kang, Keon Wook

2005-12-01

339

Bradykinin decreases nitric oxide release from microglia via inhibition of cyclic adenosine monophosphate signaling.  

PubMed

Bradykinin (BK) is a major potent inflammatory mediator outside the central nervous system. In Alzheimer's disease, BK release and BK receptor expression in brain tissues are upregulated relatively early during the course of the disease. Hence, BK was believed to promote neuroinflammation. However, BK was recently reported to possess anti-inflammatory and neuroprotective roles. Exposure of BV2 microglial cell line to BK lead to a decrease in NO release from unstimulated cells as well as a dose-dependent attenuation, mediated by both B1 and B2 receptors, in lipopolysaccharide (LPS)-induced NO production. In this study we examined whether cyclic adenosine monophosphate (cAMP) signaling is involved in BK-mediated effect in microglial nitric oxide (NO) production. A protein kinase A (PKA) inhibitor mimicked the effects of BK, while cAMP elevating agents antagonized BK-mediated NO decrease. Moreover, BK inhibited the activation of cAMP responsive element binding protein (CREB). In addition, BK protected microglial cells from death triggered by combinations of LPS and each of the cAMP elevating agents. Finally, the addition of G?i protein inhibitor abrogated the effects of BK on NO release, and the expression of G?i protein in the plasma membrane was induced by BK. These results suggest that BK-mediated reduction in microglial NO production depends on coupling to Gi protein and also involves inhibition of cAMP-PKA-CREB signaling. PMID:23340021

Ben-Shmuel, Sarit; Danon, Abraham; Fleisher-Berkovich, Sigal

2013-02-01

340

Heat shock induces resistance in rat pancreatic islet cells against nitric oxide, oxygen radicals and streptozotocin toxicity in vitro.  

PubMed Central

When cultures of pancreatic islet cells are exposed to the nitric oxide donor sodium nitroprusside, to enzymatically generated reactive oxygen intermediates or to streptozotocin cell lysis occurs after 4-12 h. We report here that a heat shock at 43 degrees C for 90 min reduces cell lysis from nitric oxide (0.45 mM sodium nitroprusside) by 70%, from reactive oxygen intermediates (12 mU xanthine oxidase and 0.05 mM hypoxanthine) by 80% and from streptozotocin (1.5 mM) by 90%. Heat shock induced resistance was observed immediately after termination of the 90 min culture at 43 degrees C and correlated with enhanced expression of hsp70. The occurrence of DNA strand breaks, a major early consequence of nitric oxide, reactive oxygen intermediates, or streptozotocin action, was not suppressed by heat shock treatment. However, the depletion of NAD+, the major cause of radical induced islet cell death, was suppressed after heat shock (P < 0.01). We conclude that pancreatic islet cells can rapidly activate defence mechanisms against nitric oxide, reactive oxygen intermediates and streptozotocin by culture at 43 degrees C. Islet cell survival is due to the prevention of lethal NAD+ depletion during DNA repair, probably by slowing down poly(ADP-ribose)polymerase activation. Images PMID:7769124

Bellmann, K; Wenz, A; Radons, J; Burkart, V; Kleemann, R; Kolb, H

1995-01-01

341

TNF-? dependent production of inducible nitric oxide is involved in PGE1 protection against acute liver injury  

PubMed Central

BACKGROUND—Tumour necrosis factor ? (TNF-?) and nitric oxide modulate damage in several experimental models of liver injury. We have previously shown that protection against D-galactosamine (D-GalN) induced liver injury by prostaglandin E1 (PGE1) was accompanied by an increase in TNF-? and nitrite/nitrate in serum.?AIMS—The aim of the present study was to evaluate the role of TNF-? and nitric oxide during protection by PGE1 of liver damage induced by D-GalN.?METHODS—Liver injury was induced in male Wistar rats by intraperitoneal injection of 1 g/kg of D-GalN. PGE1 was administered 30 minutes before D-GalN. Inducible nitric oxide synthase (iNOS) was inhibited by methylisothiourea (MT), and TNF-? concentration in serum was lowered by administration of anti-TNF-? antibodies. Liver injury was evaluated by alanine aminotransferase activity in serum, and histological examination and DNA fragmentation in liver. TNF-? and nitrite/nitrate concentrations were determined in serum. Expression of TNF-? and iNOS was also assessed in liver sections.?RESULTS—PGE1 decreased liver injury and increased TNF-? and nitrite/nitrate concentrations in serum of rats treated with D-GalN. PGE1 protection was related to enhanced expression of TNF-? and iNOS in hepatocytes. Administration of anti-TNF-? antibodies or MT blocked the protection by PGE1 of liver injury induced by D-GalN.?CONCLUSIONS—This study suggests that prior administration of PGE1 to D-GalN treated animals enhanced expression of TNF-? and iNOS in hepatocytes, and that this was causally related to protection by PGE1 against D-GalN induced liver injury.???Keywords: tumour necrosis factor ?; nitric oxide; prostaglandin E1; methylisothiourea; D-galactosamine; liver injury PMID:10986217

Muntane, J; Rodriguez, F; Segado, O; Quintero, A; Lozano, J; Siendones, E; Pedraza, C; Delgado, M; O'Valle, F; Garcia, R; Montero, J; De la Mata, M; Mino, G

2000-01-01

342

Prolonged nitric oxide treatment induces tau aggregation in SH-SY5Y cells.  

PubMed

Presence of cytoplasmic tau aggregates is a hallmark of brains in patients with tauopathies such as Alzheimer's disease. However, the mechanism underlying formation of these insoluble tau aggregates remains elusive. In this study, we investigated the impact of prolonged nitric oxide (NO) exposure on neuronal SH-SY5Y cells overexpressing human tau. Treatment with the NO donor DETA NONOate for up to 48h resulted in an increase in S-nitrosation of cellular proteins, inactivation of proteasome, and impairment of respiration. Western blot analysis of Triton X-soluble fractions of NO-treated cells revealed that persistent NO treatment increased heterogeneity in tau molecule size, as a result of dephosphorylation, and induced the formation of sodium dodecyl sulfate (SDS)-stable oligomeric tau aggregates, stabilized by disulfide bonds. Moreover, further NO treatment induced the formation of SDS-stable insoluble tau mega-aggregates that were composed of dephosphorylated full-length tau molecules and other proteins, and were stabilized through disulfide bonds. Evaluation of the role of these tau aggregates as potential seeds for tau fibrillization and elucidation of their formation mechanism in our model, could lead to better understanding of the pathogenesis of tauopathies. PMID:22249117

Takahashi, Muneaki; Chin, Yo; Nonaka, Takashi; Hasegawa, Masato; Watanabe, Nobuo; Arai, Takao

2012-02-21

343

Chronic nitric oxide deprivation induces an adaptive antioxidant status in human endothelial cells.  

PubMed

In a previous work, we showed an increased cell motility due to the accumulation and transcriptional activation of the Hypoxia Inducible Factor-1? (HIF-1?) and a reduced mitochondrial energy production in an in vitro model of endothelial dysfunction (ED) represented by human endothelial cells (ECs) chronically deprived of nitric oxide (NO) by L-NAME treatment. In the present study, in the attempt to unravel the pathway(s) linking NO deficiency to HIF-1? accumulation and activation, we focused our attention on Reactive Oxygen Species (ROS). We found that ROS were partially involved in HIF-1? stabilization, but not in the pro-migratory phenotype. Regarding mitochondrial dysfunction, it did not require neither ROS generation nor HIF-1? activity, and was not due to autophagy. Very interestingly, while acute treatment with L-NAME induced a transient increase in ROS formation, chronic NO deprivation by long term L-NAME exposure drastically reduced cellular ROS content giving rise to an antioxidant environment characterized by an increase in superoxide dismutase-2 (SOD-2) expression and activity, and by nuclear accumulation of the transcription factor NF-E2-related factor-2 (Nrf2). These results might have important implications for our understanding of the consequences of NO deprivation in endothelium behavior and in the onset of cardiovascular diseases. PMID:23917205

Cattaneo, Maria Grazia; Cappellini, Elisa; Ragni, Maurizio; Tacchini, Lorenza; Scaccabarozzi, Diletta; Nisoli, Enzo; Vicentini, Lucia Maria

2013-11-01

344

Hypoxia induces complex I inhibition and ultrastructural damage by increasing mitochondrial nitric oxide in developing CNS.  

PubMed

NO-mediated toxicity contributes to neuronal damage after hypoxia; however, the molecular mechanisms involved are still a matter of controversy. Since mitochondria play a key role in signalling neuronal death, we aimed to determine the role of nitrative stress in hypoxia-induced mitochondrial damage. Therefore, we analysed the biochemical and ultrastructural impairment of these organelles in the optic lobe of chick embryos after in vivo hypoxia-reoxygenation. Also, we studied the NO-dependence of damage and examined modulation of mitochondrial nitric oxide synthase (mtNOS) after the hypoxic event. A transient but substantial increase in mtNOS content and activity was observed at 0-2 h posthypoxia, resulting in accumulation of nitrated mitochondrial proteins measured by immunoblotting. However, no variations in nNOS content were observed in the homogenates, suggesting an increased translocation to mitochondria and not a general de novo synthesis. In parallel with mtNOS kinetics, mitochondria exhibited prolonged inhibition of maximal complex I activity and ultrastructural phenotypes associated with swelling, namely, fading of cristae, intracristal dilations and membrane disruption. Administration of the selective nNOS inhibitor 7-nitroindazole 20 min before hypoxia prevented complex I inhibition and most ultrastructural damage. In conclusion, we show here for the first time that hypoxia induces NO-dependent complex I inhibition and ultrastructural damage by increasing mitochondrial NO in the developing brain. PMID:18184317

Giusti, Sebastián; Converso, Daniela P; Poderoso, Juan J; Fiszer de Plazas, Sara

2008-01-01

345

Upregulation of hypothalamic nitric oxide synthase gene expression in streptozotocin-induced diabetic rats.  

PubMed

Plasma arginine vasopressin (AVP) is known to be elevated in patients with uncontrolled insulin-dependent diabetes mellitus who have plasma hyperosmolality with hyperglycaemia. Although osmotic stimuli cause an increase in nitric oxide synthase (NOS) activity as well as synthesis of AVP and oxytocin in the paraventricular (PVN) and supraoptic nuclei (SON), it is not known whether NOS activity in the hypothalamus changes in the diabetic patients who have plasma hyperosmolality with hyperglycaemia caused by insulin deficiency. Expression of the neuronal (n) NOS gene in the PVN and SON in streptozotocin (STZ)-induced diabetic rats was investigated by using in situ hybridization histochemistry and NADPH-diaphorase histochemical staining. Four weeks after intraperitoneal (i. p.) administration of STZ, male Wistar rats developed hyperglycaemia and plasma hyperosmolality. The expression of nNOS gene and NADPH-diaphorase staining in the PVN and SON remarkably increased in STZ-induced diabetic rats compared to control rats. Three weeks after administration of STZ, the diabetic rats were subcutaneously treated with insulin for 1 week, which resulted in significant suppression of the induction of nNOS, AVP and oxytocin gene expression in the PVN and SON. Furthermore, the induction of nNOS gene expression in the PVN and SON was suppressed in STZ-induced diabetic rats treated with phlorizin and diet to normalize hyperglycaemia without insulin treatment. These results suggest that upregulation of nNOS gene expression as well as AVP and oxytocin gene expression in the PVN and SON in STZ-induced diabetic rats may be associated with hyperglycaemia and plamsa hyperosmolality. PMID:9662044

Serino, R; Ueta, Y; Tokunaga, M; Hara, Y; Nomura, M; Kabashima, N; Shibuya, I; Hattori, Y; Yamashita, H

1998-06-01

346

Nitric oxide enhances substance P-induced itch-associated responses in mice  

PubMed Central

Substance P (SP) elicits itch and itch-associated responses in humans and mice, respectively. In mice, NK1 tachykinin receptors are involved in SP-induced itch-associated responses, scratching, and mast cells do not play a critical role. The present study was conducted to elucidate the role of nitric oxide (NO) on SP-induced scratching in mice. An intradermal injection of SP (100 nmol site?1) elicited scratching in mice, and it was suppressed by an intravenous injection of the NO synthase (NOS) inhibitor NG-nitro-L-arginine methyl ester (L-NAME), but not by its inactive enantiomer D-NAME. Intradermal injections of L-NAME (100 nmol site?1), another NOS inhibitor 7-nitroindazole (10 nmol site?1) and the NO scavenger haemoglobin (0.01–10 nmol site?1) also inhibited SP-induced scratching. L-NAME (100 nmol site?1) did not affect scratching induced by an intradermal injection of 5-hydroxytryptamine (100 nmol site?1). Intradermal injections of L-arginine (300 nmol site?1) and the NO donor (±)-(E)-4-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide (NOR3; 100 nmol site?1) increased scratching induced by SP. Intradermal injections of L-arginine (1–1000 nmol site?1) or NOR3 (1–100 nmol site?1) alone were without effects on scratching. Intradermal injections of SP (10–100 nmol site?1) increased the intradermal concentration of NO in a dose-dependent manner in mice. An increase in NO levels induced by SP was inhibited by L-NAME and the NK1 tachykinin receptor antagonist L-668,169, but not by the NK2 tachykinin receptor antagonist L-659,877. SP (1–10 ?M) elicited NO production in cultured human keratinocytes and the SP-induced NO production was inhibited by L-NAME and L-668,169. We conclude that intradermal SP increases NO in the skin, possibly through the action on NK1 tachykinin receptors on the epidermal keratinocytes and that NO enhances SP-induced itch-associated responses. PMID:12522091

Andoh, Tsugunobu; Kuraishi, Yasushi

2003-01-01

347

Influence of environmental ammonia on the production of nitric oxide and expression of inducible nitric oxide synthase in the freshwater air-breathing catfish (Heteropneustes fossilis).  

PubMed

Nitric oxide (NO) is a highly versatile and unique ubiquitous signaling molecule, and is known to play diverse physiological functions in mammals including those of adaptation to various stresses. The present study reports on the influence of exposure to high external ammonia (HEA) on the production of nitric oxide (NO) and the expression of inducible nitric oxide synthase (iNOS), that produces NO from l-arginine in the freshwater air-breathing catfish (Heteropneustes fossilis), which is reported to tolerate a very HEA. Some levels of NO were found to be present in all the tissues and also in plasma of control fish, which further enhanced significantly in fishes treated with high concentrations of environmental ammonia (25 and 50 mM ammonium chloride) for 7 days, accompanied by more efflux of NO from the perfused liver. This was accomplished by the induction of iNOS activity in different tissues of fish exposed to HEA, which otherwise was not detectable in control fish. Exposure to 25 mM ammonium chloride also led to a significant expression of iNOS protein in different tissues, followed by further increase at 50mM ammonium chloride. Further, there was an increase in the expression of iNOS mRNA in ammonia-treated fish, thus suggesting that the expression of iNOS gene under hyper-ammonia stress was probably regulated at the transcriptional level. Immunocytochemical analysis indicated that the expression of iNOS in different tissues was zonal specific and not expressed uniformly throughout the organ. Hyper-ammonia stress also led to activation and nuclear translocation of nuclear factor ?B (NF?B) in hepatic cells. These results suggest that the activation of iNOS gene under hyper-ammonia stress was probably mediated through the activation of one of the major transcription factors, the NF?B. This is the first report of ammonia-induced expression of iNOS gene, iNOS protein expression leading to more generation of NO under hyper-ammonia stress in any teleosts. PMID:22466354

Choudhury, Mahua G; Saha, Nirmalendu

2012-07-15

348

The Effects of Phorbol 12Myristate 13Acetate, Cholera Toxin, Prostaglandin E2 and Norepinephrine on Inducible Nitric Oxide Synthase Activation Induced by Lipopolysaccharide in C6 Cells  

Microsoft Academic Search

Nitric oxide (NO) plays a significant role in the pathophysiology of the central nervous system including inflammatory, ischemic and traumatic injuries. We demonstrated the possible involvement of protein kinase C (PKC) as well as protein kinase A (PKA) in the regulation of NO synthesis induced by lipopolysaccharide (LPS) treatment. In this study, the role of phorbol 12-myristate 13-acetate (PMA), cholera

Young-Jun Seo; Min-Soo Kwon; Eon-Jeong Shim; Jin-Young Lee; Hong-Won Suh

2006-01-01

349

YC-1 potentiates cAMP-induced CREB activation and nitric oxide production in alveolar macrophages  

SciTech Connect

Alveolar macrophages play significant roles in the pathogenesis of several inflammatory lung diseases. Increases in exhaled nitric oxide (NO) are well documented to reflect disease severity in the airway. In this study, we investigated the effect of 3-(5?-hydroxymethyl-2?-furyl)-1-benzyl indazole (YC-1), a known activator of soluble guanylyl cyclase, on prostaglandin (PG)E{sub 1} (a stable PGE{sub 2} analogue) and forskolin (a adenylate cyclase activator) induced NO production and inducible NO synthase (iNOS) expression in rat alveolar macrophages (NR8383). YC-1 did not directly cause NO production or iNOS expression, but drastically potentiated PGE{sub 1}- or forskolin-induced NO production and iNOS expression in NR8383 alveolar macrophages. Combination treatment with YC-1 and PGE{sub 1} significantly increased phosphorylation of the cAMP response element-binding protein (CREB), but not nuclear factor (NF)-?B activation. The combined effect on NO production, iNOS expression, and CREB phosphorylation was reversed by a protein kinase (PK)A inhibitor (H89), suggesting that the potentiating functions were mediated through a cAMP/PKA signaling pathway. Consistent with this, cAMP analogues, but not the cGMP analogue, caused NO release, iNOS expression, and CREB activation. YC-1 treatment induced an increase in PGE{sub 1}-induced cAMP formation, which occurred through the inhibition of cAMP-specific phosphodiesterase (PDE) activity. Furthermore, the combination of rolipram (an inhibitor of PDE4), but not milronone (an inhibitor of PDE3), and PGE{sub 1} also triggered NO production and iNOS expression. In summary, YC-1 potentiates PGE{sub 1}-induced NO production and iNOS expression in alveolar macrophages through inhibition of cAMP PDE activity and activation of the cAMP/PKA/CREB signaling pathway. Highlights: ? YC-1 potentiated PGE1-induced iNOS expression in alveolar macrophages. ? The combination of YC-1 and PGE1 increased CREB but not NF?B activation. ? The combined effects were reversed by H89. ? The combination of rolipram and PGE1 triggered NO production and iNOS expression. ? Effect of YC-1 occurred through inhibition of cAMP-specific PDE.

Hwang, Tsong-Long, E-mail: htl@mail.cgu.edu.tw [Graduate Institute of Natural Products, College of Medicine, Chang Gung University, Taoyuan, Taiwan (China) [Graduate Institute of Natural Products, College of Medicine, Chang Gung University, Taoyuan, Taiwan (China); Chinese Herbal Medicine Research Team, Healthy Aging Research Center, Chang Gung University, Kweishan, Taoyuan, Taiwan (China); Tang, Ming-Chi [Graduate Institute of Natural Products, College of Medicine, Chang Gung University, Taoyuan, Taiwan (China)] [Graduate Institute of Natural Products, College of Medicine, Chang Gung University, Taoyuan, Taiwan (China); Kuo, Liang-Mou [Department of General Surgery, Chang Gung Memorial Hospital at Chia-Yi, Taiwan (China)] [Department of General Surgery, Chang Gung Memorial Hospital at Chia-Yi, Taiwan (China); Chang, Wen-De; Chung, Pei-Jen; Chang, Ya-Wen; Fang, Yao-Ching [Graduate Institute of Natural Products, College of Medicine, Chang Gung University, Taoyuan, Taiwan (China)] [Graduate Institute of Natural Products, College of Medicine, Chang Gung University, Taoyuan, Taiwan (China)

2012-04-15

350

Advanced glycation endproducts co-localize with inducible nitric oxide synthase in Alzheimer's disease.  

PubMed

Advanced glycation endproducts (AGEs), protein-bound oxidation products of sugars, have been shown to be involved in the pathophysiological processes of Alzheimer's disease (AD). AGEs induce the expression of various pro-inflammatory cytokines and the inducible nitric oxide synthase (iNOS) leading to a state of oxidative stress. AGE modification and resulting crosslinking of protein deposits such as amyloid plaques may contribute to the oxidative stress occurring in AD. The aim of this study was to immunohistochemically compare the localization of AGEs and beta-amyloid (Abeta) with iNOS in the temporal cortex (Area 22) of normal and AD brains. In aged normal individuals as well as early stage AD brains (i.e. no pathological findings in isocortical areas), a few astrocytes showed co-localization of AGE and iNOS in the upper neuronal layers, compared with no astrocytes detected in young controls. In late AD brains, there was a much denser accumulation of astrocytes co-localized with AGE and iNOS in the deeper and particularly upper neuronal layers. Also, numerous neurons with diffuse AGE but not iNOS reactivity and some AGE and iNOS-positive microglia were demonstrated, compared with only a few AGE-reactive neurons and no microglia in controls. Finally, astrocytes co-localized with AGE and iNOS as well as AGE and were found surrounding mature but not diffuse amyloid plaques in the AD brain. Our results show that AGE-positive astrocytes and microglia in the AD brain express iNOS and support the evidence of an AGE-induced oxidative stress occurring in the vicinity of the characteristic lesions of AD. Hence activation of microglia and astrocytes by AGEs with subsequent oxidative stress and cytokine release may be an important progression factor in AD. PMID:11716809

Wong, A; Lüth, H J; Deuther-Conrad, W; Dukic-Stefanovic, S; Gasic-Milenkovic, J; Arendt, T; Münch, G

2001-11-30

351

Protective Vascular and Cardiac Effects of Inducible Nitric Oxide Synthase in Mice with Hyperhomocysteinemia  

PubMed Central

Diet-induced hyperhomocysteinemia produces endothelial and cardiac dysfunction and promotes thrombosis through a mechanism proposed to involve oxidative stress. Inducible nitric oxide synthase (iNOS) is upregulated in hyperhomocysteinemia and can generate superoxide. We therefore tested the hypothesis that iNOS mediates the adverse oxidative, vascular, thrombotic, and cardiac effects of hyperhomocysteinemia. Mice deficient in iNOS (Nos2?/?) and their wild-type (Nos2+/+) littermates were fed a high methionine/low folate (HM/LF) diet to induce mild hyperhomocysteinemia, with a 2-fold increase in plasma total homocysteine (P<0.001 vs. control diet). Hyperhomocysteinemic Nos2+/+ mice exhibited endothelial dysfunction in cerebral arterioles, with impaired dilatation to acetylcholine but not nitroprusside, and enhanced susceptibility to carotid artery thrombosis, with shortened times to occlusion following photochemical injury (P<0.05 vs. control diet). Nos2?/? mice had decreased rather than increased dilatation responses to acetylcholine (P<0.05 vs. Nos2+/+ mice). Nos2?/? mice fed control diet also exhibited shortened times to thrombotic occlusion (P<0.05 vs. Nos2+/+ mice), and iNOS deficiency failed to protect from endothelial dysfunction or accelerated thrombosis in mice with hyperhomocysteinemia. Deficiency of iNOS did not alter myocardial infarct size in mice fed the control diet but significantly increased infarct size and cardiac superoxide production in mice fed the HM/LF diet (P<0.05 vs. Nos2+/+ mice). These findings suggest that endogenous iNOS protects from, rather than exacerbates, endothelial dysfunction, thrombosis, and hyperhomocysteinemia-associated myocardial ischemia-reperfusion injury. In the setting of mild hyperhomocysteinemia, iNOS functions to blunt cardiac oxidative stress rather than functioning as a source of superoxide. PMID:25226386

Dayal, Sanjana; Blokhin, Ilya O.; Erger, Rochelle A.; Jensen, Melissa; Arning, Erland; Stevens, Jeff W.; Bottiglieri, Teodoro; Faraci, Frank M.; Lentz, Steven R.

2014-01-01

352

Inhibition of Inducible Nitric Oxide Synthase Expression by a Novel Small Molecule Activator of the Unfolded Protein Response  

PubMed Central

The transcription of inducible nitric oxide synthase (iNOS) is activated by a network of proinflammatory signaling pathways. Here we describe the identification of a small molecule that downregulates the expression of iNOS mRNA and protein in cytokine-activated cells and suppresses nitric oxide production in vivo. Mechanistic analysis suggests that this small molecule, erstressin, also activates the unfolded protein response (UPR), a signaling pathway triggered by endoplasmic reticulum stress. Erstressin induces rapid phosphorylation of eIF2? and the alternative splicing of XBP-1, hallmark initiating events of the UPR. Further, erstressin activates the transcription of multiple genes involved in the UPR. These data suggest an inverse relationship between UPR activation and iNOS mRNA and protein expression under proinflammatory conditions. PMID:20161838

Symons, Kent T; Massari, Mark E; Dozier, Sara J; Nguyen, Phan M; Jenkins, David; Herbert, Mark; Gahman, Timothy C; Noble, Stewart A; Rozenkrants, Natasha; Zhang, Yan; Rao, Tadimeti S; Shiau, Andrew K; Hassig, Christian A

2008-01-01

353

Effects of polysaccharides from Morchella conica on nitric oxide production in lipopolysaccharide-treated macrophages.  

PubMed

Morchella conica is a species of rare edible mushroom whose multiple medicinal functions have been proven. However, reports barely mention the mechanisms of these functions. In this study, the effects of two polysaccharides from M. conica (PMCs) on nitric oxide (NO) production in lipopolysaccharide (LPS)-treated macrophages were investigated. The results showed that 50-200 ?g/ml of the extracellular polysaccharide (EPMC) and 25-200 ?g/ml of the intracellular polysaccharide (IPMC) significantly inhibited NO production. Accordingly, the signal mechanisms were also explored. It was found that 100 ?g/ml of EPMC and 25 ?g/ml of IPMC could efficiently down-regulate the inducible nitric oxide synthase (iNOS) expression and nuclear factor-?B (NF-?B) DNA-binding activity and up-regulate heme oxygenase 1 (HO-1) expression. Moreover, by using a HO-1 inhibitor NaPP to treat the cells, the PMC-inhibited NO production and iNOS expression, rather than NF-?B activation, were released partially, indicating that HO-1 probably medicates the inhibition of PMCs on iNOS and NO. Besides, EPMC also significantly suppressed the phosphorylation of p38 mitogen-activated protein kinase (p38), c-jun N-terminal kinase, mitogen-activated protein kinase kinase 4, and expression of NF-?B inducing kinase, while IPMC seemed to show no regular effect on p38. In conclusion, PMCs inhibited NO production in LPS-induced macrophages through regulating a series of signal pathways, suggesting that PMCs play a potential role on immunomodulation and treating related diseases. PMID:22159604

Huang, Mian; Zhang, Song; Zhang, Minglong; Ou, Shangkang; Pan, Zhifu

2012-05-01

354

Comparison of the effect of inhaled nitric oxide and intravenous nitroglycerine on hypoxia-induced pulmonary hypertension in pigs.  

PubMed

Pulmonary hypertension is usually treated with intravenous (i.v.) vasodilators, but their use is limited by systemic effects. In the current study, we compared the effects of inhaled nitric oxide and intravenous nitroglycerine on pulmonary and systemic haemodynamic responses as well as on gas exchange measurements in anaesthetized pigs whose pulmonary pressure was increased by hypoxia (FiO2 = 15%). Both treatments reduced pulmonary pressure to the control level. Inhaled nitric oxide did not affect systemic arterial pressure but intravenous nitroglycerine decreased it from 126.2 to 108.8 mmHg (P = 0.04). Unlike intravenous nitroglycerine, inhaled nitric oxide increased arterial PaO2 from 5.3 to 5.9 kPa (P = 0.02). Both treatments diminished central venous pressure and left atrial pressure, suggesting a possible cardiac effect. Inhaled nitric oxide was shown to be a potent pulmonary vasodilator which attenuated pulmonary hypertension and improved arterial oxygenation without important direct effects on systemic pressure in porcine hypoxia-induced pulmonary hypertension. PMID:8889430

Troncy, E; Jacob, E; da Silva, P; Ducruet, T; Collet, J P; Salazkin, I; Charbonneau, M; Blaise, G

1996-09-01

355

Gaseous Nitric Oxide-Induced 8-Nitroguanine Formation in Human Lung Fibroblast Cells and Cell-Free DNA  

Microsoft Academic Search

A time- and dose-dependent increase in 8-nitroguanine (8-NO2-G) was observed in human lung fibroblast cells (MRC-5) after treatment with gaseous NO-saturated buffer. It was also found that treatment with the inhibitor of inducible nitric oxide synthase (iNOS), NG-nitro-l-arginine methyl ester, significantly reduced the 8-NO2-G level in the gaseous NO-saturated buffer-treated MRC-5 cells. These results provide evidence indicating that NO gas

Yih-Shou Hsieh; Hsue-Chun Wang; Tsui-Hwa Tseng; Wen-Cheng Chang; Chau-Jong Wang

2001-01-01

356

Increased Expression of Inducible Nitric Oxide Synthase and Cyclooxygenase2 in Barrett's Esophagus and Associated Adenocarcinomas1  

Microsoft Academic Search

Barrett's esophagus is a premalignant condition arising in response to chronic reflux esophagitis. Inducible nitric oxide synthase (¡NOS;NOS-2) and cyclooxygenase-2 (COX-2) are mediators of inflammation and regu lators of epithelial cell growth. Expression levels of ¡NOS and COX-2 are high in colorectal adenomas and carcinomas, and COX-2 expression is elevated in gastric cancers. To determine the involvement of ¡NOSand COX-2

Keith T. Wilson; Sidong Fu; Kalathur S. Ramanujam; Stephen J. Meltzer

1998-01-01

357

Protective effects of epigallocatechin gallate following 3-nitropropionic acid-induced brain damage: possible nitric oxide mechanisms  

Microsoft Academic Search

Introduction  The role of oxidative stress has been well known in neurodegenerative disorders. 3-Nitropropionic acid (3-NP) is a plant-based\\u000a mycotoxin that produces HD like symptoms in animals. Oxidative stress and nitric oxide mechanisms have been recently proposed\\u000a in the 3-NP-induced neurotoxicity. Epigallocatechin gallate (EGCG) is one of the major components of green tea, known for\\u000a its potent antioxidant activity. Besides, neuroprotective

Puneet Kumar; Anil Kumar

2009-01-01

358

Effects of inducible nitric oxide synthase blockade within the periaqueductal gray on cardiovascular responses during mechanical, heat, and cold nociception  

Microsoft Academic Search

We have examined the role of inducible nitric oxide synthase (iNOS) within the dorsolateral periaqueductal gray mater (dlPAG)\\u000a on cardiovascular responses during mechanical, thermal, and cold nociception in anesthetized rats. Mechanical stimulus was\\u000a applied by a unilateral hindpaw pinch for 10 s that increased mean arterial pressure (MAP) and heart rate (HR). Bilateral\\u000a microdialysis of a selective iNOS inhibitor, aminoguanidine (AGN;

Kevin A. Chaitoff; Francis Toner; Anthony Tedesco; Timothy J. Maher; Ahmmed Ally

359

Selective inhibition of inducible nitric oxide synthase reduces neurological deficit but not cerebral edema following traumatic brain injury  

Microsoft Academic Search

The role of inducible nitric oxide synthase (iNOS) in cerebral edema and neurological deficit following traumatic brain injury (TBI) is not yet clear-cut. Therefore, the aim of this study was to investigate the effect of three different iNOS inhibitors on cerebral edema and functional outcome after TBI. First, the time courses of blood–brain barrier (BBB) breakdown, cerebral edema, and neurological

G. Louin; C. Marchand-Verrecchia; B. Palmier; M. Plotkine; M. Jafarian-Tehrani

2006-01-01

360

Inorganic Phosphate Induces Mammalian Growth Plate Chondrocyte Apoptosis in a Mitochondrial Pathway Involving Nitric Oxide and JNK MAP Kinase  

Microsoft Academic Search

Chondrocytes in the hypertrophic zone of the growth plate undergo apoptosis during endochondral bone development via mechanisms\\u000a that involve inorganic phosphate (Pi) and nitric oxide (NO). Recent evidence suggests that Pi-dependent NO production plays\\u000a a role in apoptosis of cells in the resting zone as well. This study examined the mechanism by which Pi induces NO production\\u000a and the signaling

M. Zhong; D. H. Carney; H. Jo; B. D. Boyan; Z. Schwartz

2011-01-01

361

Nitric oxide modulates pepsinogen secretion induced by calcium-mediated agonist in guinea pig gastric chief cells  

Microsoft Academic Search

Background & Aims: Nitric oxide, a putative cellular messenger synthesized from l-arginine, is a powerful modulator of gastric motility and secretions. The aim of this study was to investigate whether (1) guinea pig gastric chief cells express NO synthase, (2) NO modulates the pepsinogen secretion and guanosine 3?,5?-cyclic monophosphate (cGMP) generation induced by calcium (Ca2+)-mediated agents, and (3) NO donors

Stefano Fiorucci; Eleonora Distrutti; Mihnea Chiorean; Luca Santucci; Silvia Belia; Giorgio Fano; Roberto de Giorgio; Vincenzo Stanghellini; Roberto Corinaldesi; Antonio Morelli

1995-01-01

362

High glucose decreases intracellular glutathione concentrations and upregulates inducible nitric oxide synthase gene expression in intestinal epithelial cells  

Microsoft Academic Search

Diabetes is associated with oxidative stress and increased concentrations of inflammatory cytokines. The aim of the study was to assess the effects of inflammatory cytokines and oxidative stress associated with increased glucose concentrations on inducible nitric oxide synthase (iNOS) promoter activity in intestinal epithelial cells. High-glucose (25 mmol\\/l) conditions reduced glutathione (GSH) concentrations in the human intestinal epithelial cell line,

Lesley A Powell; Katherine M Warpeha; Weiming Xu; Brian Walker; Elisabeth R Trimble

2004-01-01

363

Extrinsic nitric oxide donor partially reverses arginine deiminase induced cell growth inhibition through NF ? B and Bcl -X L  

Microsoft Academic Search

Summary  Arginine deiminase (ADI) is known to be an inducer of apoptosis in vitro and an anti-tumor agent in vivo in some cancers.\\u000a ADI causes the enzymatic depletion of arginine which may inhibit nitric oxide (NO) synthesis. However, the effect of ADI treatment\\u000a on NO synthesis has not been clearly elucidated. With the goal of understanding the role of ADI in

Jae Hong Seo; Hwa Jung Sung; Chul Won Choi; Byung Soo Kim; Sang Won Shin; Yeul Hong Kim; Bon Hong Min; Jun Suk Kim

2008-01-01

364

Inducible nitric oxide synthase, nitrotyrosine and apoptosis in gastric adenocarcinomas and their correlation with a poor survival  

Microsoft Academic Search

Abstract Abstract Abstract Abstract AIM: To detect the presence of inducible nitric oxide synthase (iNOS), nitrotyrosine (NT) and apoptosis in gastric adenocarcinomas and their possible correlations with the clinicopathological characteristics and prognosis of gastric adenocarcinoma. METHODS: Sixty-six specimens of gastric adenocarcinoma and corresponding adjacent normal gastric tissues were studied. Immunohistochemistry was employed to localize iNOS and NT protein and an

Long-Gang Li; Hui-Mian Xu

2005-01-01

365

Laser induced fluorescence measurements and modeling of nitric oxide in high-pressure premixed flames  

NASA Technical Reports Server (NTRS)

Laser-induced fluorescence (LIF) has been applied to the quantitative measurement of nitric oxide (NO) in premixed, laminar, high-pressure flames. Their chemistry was also studied using three current kinetics schemes to determine the predictive capabilities of each mechanism with respect to NO concentrations. The flames studied were low-temperature (1600 less than T less than 1850K) C2H6/O2/N2 and C2H6/O2/N2 flames, and high temperature (2100 less than T less than 2300K) C2H6/O2/N2 flames. Laser-saturated fluorescence (LSF) was initially used to measure the NO concentrations. However, while the excitation transition was well saturated at atmospheric pressure, the fluorescence behavior was basically linear with respect to laser power at pressures above 6 atm. Measurements and calculations demonstrated that the fluorescence quenching rate variation is negligible for LIF measurements of NO at a given pressure. Therefore, linear LIF was used to perform quantitative measurements of NO concentration in these high-pressure flames. The transportability of a calibration factor from one set of flame conditions to another also was investigated by considering changes in the absorption and quenching environment for different flame conditions. The feasibility of performing LIF measurements of (NO) in turbulent flames was studied; the single-shot detection limit was determined to be 2 ppm.

Reisel, John R.; Laurendeau, Normand M.

1994-01-01

366

Nitric oxide in microgravity-induced orthostatic intolerance: relevance to spinal cord injury  

NASA Technical Reports Server (NTRS)

Prolonged exposure to microgravity results in cardiovascular deconditioning which is marked by orthostatic intolerance in the returning astronauts and recovering bed-ridden patients. Recent studies conducted in our laboratories at University of California, Irvine have revealed marked elevation of nitric oxide (NO) pr