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1

Nitric oxide suppresses NLRP3 inflammasome activation and protects against LPS-induced septic shock  

PubMed Central

Inflammasomes are multi-protein complexes that trigger the activation of caspase-1 and the maturation of interleukin-1? (IL-1?), yet the regulation of these complexes remains poorly characterized. Here we show that nitric oxide (NO) inhibited the NLRP3-mediated ASC pyroptosome formation, caspase-1 activation and IL-1? secretion in myeloid cells from both mice and humans. Meanwhile, endogenous NO derived from iNOS (inducible form of NO synthase) also negatively regulated NLRP3 inflammasome activation. Depletion of iNOS resulted in increased accumulation of dysfunctional mitochondria in response to LPS and ATP, which was responsible for the increased IL-1? production and caspase-1 activation. iNOS deficiency or pharmacological inhibition of NO production enhanced NLRP3-dependent cytokine production in vivo, thus increasing mortality from LPS-induced sepsis in mice, which was prevented by NLRP3 deficiency. Our results thus identify NO as a critical negative regulator of the NLRP3 inflammasome via the stabilization of mitochondria. This study has important implications for the design of new strategies to control NLRP3-related diseases.

Mao, Kairui; Chen, Shuzhen; Chen, Mingkuan; Ma, Yonglei; Wang, Yan; Huang, Bo; He, Zhengyu; Zeng, Yan; Hu, Yu; Sun, Shuhui; Li, Jing; Wu, Xiaodong; Wang, Xiangrui; Strober, Warren; Chen, Chang; Meng, Guangxun; Sun, Bing

2013-01-01

2

Constituents of Limonia acidissima inhibit LPS-induced nitric oxide production in BV-2 microglia.  

PubMed

The ethyl acetate (EtOAc) soluble fraction of the 85% ethanol (EtOH) extract of the dried bark of Limonia acidissima potently inhibited nitric oxide (NO) production in lipopolysaccharide (LPS) activated BV-2 cells, a microglial cell line. Bioassay-guided column chromatography separation afforded a new stereoisomer of neolignan, (7'E)-(7R,8S)-4-hydroxy-3,5'-dimethoxy-4',7-epoxy-8,3'-neolig-7'-en-9,9'-diyil diacetate (1), together with two known lignans, (+)-yangambin (2) and (+)-syringaresinol (3), three known triterpenoids, hederatriol (4), basic acid methyl ester (5), and 3?-hydroxyolean-12-en-11-one (6), and four known fatty acid derivatives, cascarillic acid (7), (+)-?-dimorphecolic acid (8), 8(R)-hydroxylinoleic acid (9), and (6Z,9Z,12Z)-pentadecatrienoic acid (10). The structure of the new compound 1 was elucidated by detailed analysis of spectroscopic data and circular dichroism (CD) spectroscopy. Compounds 1, 3-6, and 8-10 isolated from L. acidissima significantly reduced NO production in LPS-stimulated BV-2 microglia cells. PMID:20578973

Kim, Ki Hyun; Ha, Sang Keun; Kim, Sun Yeou; Youn, Hyun Joo; Lee, Kang Ro

2010-06-28

3

Hypericum triquetrifolium-Derived Factors Downregulate the Production Levels of LPS-Induced Nitric Oxide and Tumor Necrosis Factor-? in THP-1 Cells.  

PubMed

Based on knowledge from traditional Arab herbal medicine, this in vitro study aims to examine the anti-inflammatory mechanism of Hypericum triquetrifolium by measuring the expression and release of pro-inflammatory cytokines, tumor necrosis factor-? (TNF-?) and interleukine-6 (IL-6), and inducible nitric oxide synthase (iNOS) in human monocytic cells, THP-1. The effects were assessed by measuring the levels of secretory proteins and mRNA of TNF-? and IL-6, the levels of nitric oxide (NO) secretion and the expression of iNOS in THP-1 cells. Cells were treated with 5??g lipopolysaccharide/ml (LPS) in the presence and absence of increasing concentrations of extracts from the aerial parts of H. triquetrifolium. During the entire experimental period, we used extract concentrations (up to 250??g?mL(-1)) that had no cytotoxic effects, as measured with MTT and LDH assays. Hypericum triquetrifolium extracts remarkably suppressed the LPS-induced NO release, significantly attenuated the LPS-induced transcription of iNOS and inhibited in a dose-dependent manner the expression and release of TNF-?. No significant effects were observed on the release of IL-6. Taken together, these results suggest that H. triquetrifolium probably exerts anti-inflammatory effects through the suppression of TNF-? and iNOS expressions. PMID:18955363

Saad, Bashar; Abouatta, Bernadette Soudah; Basha, Walid; Hmade, Alaa; Kmail, Abdalsalam; Khasib, Said; Said, Omar

2011-02-20

4

Hypericum triquetrifolium--Derived Factors Downregulate the Production Levels of LPS-Induced Nitric Oxide and Tumor Necrosis Factor-? in THP-1 Cells  

PubMed Central

Based on knowledge from traditional Arab herbal medicine, this in vitro study aims to examine the anti-inflammatory mechanism of Hypericum triquetrifolium by measuring the expression and release of pro-inflammatory cytokines, tumor necrosis factor-? (TNF-?) and interleukine-6 (IL-6), and inducible nitric oxide synthase (iNOS) in human monocytic cells, THP-1. The effects were assessed by measuring the levels of secretory proteins and mRNA of TNF-? and IL-6, the levels of nitric oxide (NO) secretion and the expression of iNOS in THP-1 cells. Cells were treated with 5??g lipopolysaccharide/ml (LPS) in the presence and absence of increasing concentrations of extracts from the aerial parts of H. triquetrifolium. During the entire experimental period, we used extract concentrations (up to 250??g?mL?1) that had no cytotoxic effects, as measured with MTT and LDH assays. Hypericum triquetrifolium extracts remarkably suppressed the LPS-induced NO release, significantly attenuated the LPS-induced transcription of iNOS and inhibited in a dose-dependent manner the expression and release of TNF-?. No significant effects were observed on the release of IL-6. Taken together, these results suggest that H. triquetrifolium probably exerts anti-inflammatory effects through the suppression of TNF-? and iNOS expressions.

Saad, Bashar; AbouAtta, Bernadette Soudah; Basha, Walid; Hmade, Alaa; Kmail, Abdalsalam; Khasib, Said; Said, Omar

2011-01-01

5

Characterization and Online Detection of Surfactin Isomers Based on HPLC-MSn Analyses and Their Inhibitory Effects on the Overproduction of Nitric Oxide and the Release of TNF-? and IL-6 in LPS-Induced Macrophages  

PubMed Central

A rapid method for characterization and online detection of surfactin isomers was developed based on HPLC-MSn (n = 1, 2, 3) analyses, and many surfactin isomers were detected and characterized from the bioactive fraction of the mangrove bacterium Bacillus sp. Inhibitory activities of surfactin isomers on the overproduction of nitric oxide and the release of TNF-? and IL-6 in LPS-induced macrophages were systematically investigated. It was revealed that the surfactin isomers showed strong inhibitory properties on the overproduction of nitric oxide and the release of IL-6 on LPS-induced murine macrophage cell RAW264.7 with IC50 values ranging from 1.0 to 7.0 ?M. Structure-activity relationship (SAR) studies revealed that the existence of the free carboxyl group in the structure of surfactin isomers was crucial. These findings will be very helpful for the development of this novel kind of natural product as new anti-inflammatory agents.

Tang, Jin-Shan; Zhao, Feng; Gao, Hao; Dai, Yi; Yao, Zhi-Hong; Hong, Kui; Li, Jia; Ye, Wen-Cai; Yao, Xin-Sheng

2010-01-01

6

Hypericum triquetrifolium—Derived Factors Downregulate the Production Levels of LPS-Induced Nitric Oxide and Tumor Necrosis Factor-a in THP1 Cells  

Microsoft Academic Search

Based on knowledge from traditional Arab herbal medicine, this in vitro study aims to examine the anti-inflammatory mechanism of Hypericum triquetrifolium by measuring the expression and release of pro-inflammatory cytokines, tumor necrosis factor-a (TNF-a) and interleukine-6 (IL-6), and inducible nitric oxide synthase (iNOS) in human monocytic cells, THP-1. The effects were assessed by measuring the levels of secretory proteins and

Bashar Saad; Bernadette Soudah AbouAtta; Walid Basha; Alaa Hmade; Abdalsalam Kmail; Said Khasib; Shefa Amr

2008-01-01

7

Achillea millefolium L. Essential Oil Inhibits LPS-Induced Oxidative Stress and Nitric Oxide Production in RAW 264.7 Macrophages  

PubMed Central

Achillea millefolium L. is a member of the Asteraceae family and has been used in folk medicine in many countries. In this study, 19 compounds in A. millefolium essential oil (AM-EO) have been identified; the major components are artemisia ketone (14.92%), camphor (11.64%), linalyl acetate (11.51%) and 1,8-cineole (10.15%). AM-EO can suppress the inflammatory responses of lipopolysaccharides (LPS)-stimulated RAW 264.7 macrophages, including decreased levels of cellular nitric oxide (NO) and superoxide anion production, lipid peroxidation and glutathione (GSH) concentration. This antioxidant activity is not a result of increased superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities, but rather occurs as a result of the down-regulation of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-? (TNF-?), interleukin-6 (IL-6) and heme oxygenase-1 (HO-1) expression, thus reducing the inflammatory response. Therefore, AM-EO can be utilized in many applications, including the treatment of inflammatory diseases in the future.

Chou, Su-Tze; Peng, Hsin-Yi; Hsu, Jaw-Cherng; Lin, Chih-Chien; Shih, Ying

2013-01-01

8

Achillea millefolium L. Essential Oil Inhibits LPS-Induced Oxidative Stress and Nitric Oxide Production in RAW 264.7 Macrophages.  

PubMed

Achillea millefolium L. is a member of the Asteraceae family and has been used in folk medicine in many countries. In this study, 19 compounds in A. millefolium essential oil (AM-EO) have been identified; the major components are artemisia ketone (14.92%), camphor (11.64%), linalyl acetate (11.51%) and 1,8-cineole (10.15%). AM-EO can suppress the inflammatory responses of lipopolysaccharides (LPS)-stimulated RAW 264.7 macrophages, including decreased levels of cellular nitric oxide (NO) and superoxide anion production, lipid peroxidation and glutathione (GSH) concentration. This antioxidant activity is not a result of increased superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities, but rather occurs as a result of the down-regulation of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-? (TNF-?), interleukin-6 (IL-6) and heme oxygenase-1 (HO-1) expression, thus reducing the inflammatory response. Therefore, AM-EO can be utilized in many applications, including the treatment of inflammatory diseases in the future. PMID:23797659

Chou, Su-Tze; Peng, Hsin-Yi; Hsu, Jaw-Cherng; Lin, Chih-Chien; Shih, Ying

2013-06-24

9

The immunoproteasomes regulate LPS-induced TRIF/TRAM signaling pathway in murine macrophages.  

PubMed

We have proposed the novel concept that the macrophage ubiquitin-proteasome pathway functions as a key regulator of Lipopolysaccharide (LPS)-induced inflammation signaling. These findings suggest that proteasome-associated protease subunits X, Y, and Z are replaced by LMP subunits after LPS treatment of RAW 264.7 cells. The objective here was to determine the contribution of selective LMP proteasomal subunits to LPS-induced nitric oxide (NO) and TNF-? production in primary murine macrophages. Accordingly, thioglycollate-elicited macrophages from LMP7, LMP2, LMP10 (MECL-1), and LMP7/MECL-1 double knockout mice were stimulated in vitro with LPS, and were found to generate markedly reduced NO levels compared to wild-type (WT) mice, whereas TNF-? levels responses were essentially unaltered relative to wild-type responses. The recent studies suggest that the TRIF/TRAM pathway is defective in LMP knockouts which may explain why iNOS/NO are not robustly induced in LPS-treated macrophages from knockouts. Treating these macrophages with IFN-? and LPS, however, reverses this defect, leading to robust NO induction. TNF-? is induced by LPS in the LMP knockout macrophages because I?B and IRAK are degraded normally via the MyD88 pathway. Collectively, these findings strongly support the concept that LMP7/MECL-1 proteasomes subunits actively function to regulate LPS-induced NO production by affecting the TRIF/TRAM pathway. PMID:21455681

Reis, Julia; Hassan, Ferdaus; Guan, Xiu Qin; Shen, Jing; Monaco, John J; Papasian, Christopher J; Qureshi, Asaf A; Van Way, Charles W; Vogel, Stefanie N; Morrison, David C; Qureshi, Nilofer

2011-06-01

10

Sphingosine Kinase 1 Deficiency Exacerbates LPS-Induced Neuroinflammation  

PubMed Central

The pathogenesis of inflammation in the central nervous system (CNS), which contributes to numerous neurodegenerative diseases and results in encephalopathy and neuroinflammation, is poorly understood. Sphingolipid metabolism plays a crucial role in maintaining cellular processes in the CNS, and thus mediates the various pathological consequences of inflammation. For a better understanding of the role of sphingosine kinase activation during neuroinflammation, we developed a bacterial lipopolysaccharide (LPS)-induced brain injury model. The onset of the inflammatory response was observed beginning 4 hours after intracerebral injection of LPS into the lateral ventricles of the brain. A comparison of established neuroinflammatory parameters such as white matter rarefactions, development of cytotoxic edema, astrogliosis, loss of oligodendrocytes, and major cytokines levels in wild type and knockout mice suggested that the neuroinflammatory response in SphK1?/? mice was significantly upregulated. At 6 hours after intracerebroventricular injection of LPS in SphK1?/? mice, the immunoreactivity of the microglia markers and astrocyte marker glial fibrillary acidic protein (GFAP) were significantly increased, while the oligodendrocyte marker O4 was decreased compared to WT mice. Furthermore, western blotting data showed increased levels of GFAP. These results suggest that SphK1 activation is involved in the regulation of LPS induced brain injury. Research Highlights • Lipopolysaccharide (LPS) intracerebral injection induces severe neuroinflammation. • Sphingosine kinase 1 deletion worsens the effect of the LPS. • Overexpression of SphK1 might be a potential new treatment approach to neuroinflammation.

Grin'kina, Natalia M.; Karnabi, Eddy E.; Damania, Dushyant; Wadgaonkar, Sunil; Muslimov, Ilham A.; Wadgaonkar, Raj

2012-01-01

11

Dioscoreanone suppresses LPS-induced nitric oxide production and inflammatory cytokine expression in RAW 264.7 macrophages by NF-?B and ERK1/2 signaling transduction.  

PubMed

Dioscoreanone, a 1,4-phenanthraquinone isolated from an ethanolic extract of the rhizome of Dioscorea membranacea, Pierre ex Prain & Burkill, a plant which has been used to treat inflammation and cancer in Thai Traditional Medicine. In this study, the mechanisms of dioscoreanone on LPS-induced NO production and cytokine expression through the activation of NF-?B and ERK1/2 are demonstrated in RAW 264.7 cells. Through measurement with Griess reagent, dioscoreanone was found to reduce NO levels with an IC(50) value of 2.50?±?0.64?µM, due to the significant suppression of LPS-induced iNOS mRNA expression, as well as IL-1? and IL-6 levels at a concentration of 6?µM. At the signal transduction level, using the pNF?B-Luciferase reporter system, dioscoreanone significantly inhibited NF-?B transcriptional activity, which resulted from the prevention of I?B? degradation. In addition, dioscoreanone in the range of 1.2-5?µM significantly enhanced LPS-induced ERK1/2 activation and dioscoreanone alone induced the activation of ERK1/2 proteins in a concentration- and time-dependent response. The activation of ERK1/2 proteins by dioscoreanone was due to both an arylating reaction, which was suppressed by N-acetyl cysteine, and a redox cycling reaction of NQOR, which was inhibited by dicoumarol. In conclusion, the mechanisms of dioscoreanone on the inhibition of NO production and mRNA expression of iNOS, IL-1?, and IL-6 were due to both the inhibition of NF-?B activation and the activation of ERK1/2 proteins. The activation of dioscoreanone may in turn inhibit the binding of NF-?B to pro-inflammatory gene promoters in LPS-induced RAW264.7 macrophage cells. PMID:22678775

Itharat, Arunporn; Hiransai, Poonsit

2012-11-01

12

Suppression of LPS-induced inflammatory activities by Rosmarinus officinalis L.  

PubMed

Rosemary (Rosmarinus officinalis L.) has been used in folk medicine to treat headaches, epilepsy, poor circulation, and many other ailments. It was found that rosemary could act as a stimulant and mild analgesic and could reduce inflammation. However, the mechanisms underlying the anti-inflammatory effects of rosemary need more study to be established. Therefore, in this study, the effects of rosemary on the activation of nuclear factor kappa beta (NF-kB) and mitogen-activated protein kinases (MAPKs), the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and the production of nitric oxide (NO), prostaglandin E(2) (PGE(2)), and cytokine in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells were investigated. A methanol extract of rosemary and its hexane fraction reduced NO generation with an IC(50) of 2.75 and 2.83 ?g/ml, respectively. Also, the methanol extract and the hexane fraction inhibited LPS-induced MAPKs and NF-kB activation associated with the inhibition of iNOS or COX-2 expression. LPS-induced production of PGE(2) and tumour necrosis factor-alpha (TNF-?) were blocked by rosemary. Rosemary extract and its hexane fraction are important for the prevention of phosphorylation of MAPKs, thereby blocking NF-kB activation, which in turn leads to decreased expression of iNOS and COX-2, thus preventing inflammation. PMID:23122161

Yu, Mi-Hee; Choi, Jun-Hyeok; Chae, In-Gyeong; Im, Hyo-Gwon; Yang, Seun-Ah; More, Kunal; Lee, In-Seon; Lee, Jinho

2012-09-12

13

TNF? Mediates LPS-Induced Microglial Toxicity to Developing Oligodendrocytes When Astrocytes Are Present  

PubMed Central

Reactive microglia and astrocytes are present in lesions of white matter disorders, such as periventricular leukomalacia and multiple sclerosis. However, it is not clear whether they are actively involved in the pathogenesis of these disorders. Previous studies demonstrated that microglia, but not astrocytes, are required for lipopolysaccharide (LPS)-induced selective killing of developing oligodendrocytes (preOLs), and that the toxicity is mediated by microglia-derived peroxynitrite. Here we report that when astrocytes are present, the LPS-induced, microglia-dependent toxicity to preOLs is no longer mediated by peroxynitrite but instead by a mechanism dependent on TNF? signaling. Blocking peroxynitrite formation with nitric oxide synthase (NOS) inhibitors or a decomposition catalyst did not prevent LPS-induced loss of preOLs in mixed glial cultures. PreOLs were highly vulnerable to peroxynitrite; however, the presence of astrocytes prevented the toxicity. While LPS failed to kill preOLs in cocultures of microglia and preOLs deficient in inducible NOS (iNOS) or gp91phox, the catalytic subunit of the superoxide-generating NADPH oxidase, LPS caused a similar degree of preOL death in mixed glial cultures of wildtype, iNOS-/- and gp91phox-/- mice. TNF? neutralizing antibody inhibited LPS toxicity, and addition of TNF? induced selective preOL injury in mixed glial cultures. Furthermore, disrupting the genes encoding TNF? or its receptors TNFR1/2 completely abolished the deleterious effect of LPS. Our results reveal that TNF? signaling, rather than peroxynitrite, is essential in LPS-triggered preOL death in an environment containing all major glial cell types, and underscore the importance of intercellular communication in determining the mechanism underlying inflammatory preOL death.

Li, Jianrong; Radhika Ramenaden, E.; Peng, Jie; Koito, Hisami; Volpe, Joseph J.; Rosenberg, Paul A.

2009-01-01

14

Intermedin Attenuates LPS-induced Inflammation in the Rat Testis  

PubMed Central

First reported as a vasoactive peptide in the cardiovascular system, intermedin (IMD), also known as adrenomedullin 2 (ADM2), is a hormone with multiple potent roles, including its antioxidant action on the pulmonary, central nervous, cardiovascular and renal systems. Though IMD may play certain roles in trophoblast cell invasion, early embryonic development and cumulus cell-oocyte interaction, the role of IMD in the male reproductive system has yet to be investigated. This paper reports our findings on the gene expression of IMD, its receptor components and its protein localization in the testes. In a rat model, bacterial lippolysaccharide (LPS) induced atypical orchitis, and LPS treatment upregulated the expression of IMD and one of its receptor component proteins, i.e. receptor activity modifying protein 2 (RAMP2). IMD decreased both plasma and testicular levels of reactive oxygen species (ROS) production, attenuated the increase in the gene expression of the proinflammatory cytokines tumor necrosis factor alpha (TNF?), interleukin 6 (IL6) and interleukin 1 beta (IL1?), rescued spermatogenesis, and prevented the decrease in plasma testosterone levels caused by LPS. The restorative effect of IMD on steroidogenesis was also observed in hydrogen peroxide-treated rat primary Leydig cells culture. Our results indicate IMD plays an important protective role in spermatogenesis and steroidogenesis, suggesting therapeutic potential for IMD in pathological conditions such as orchitis.

Liu, Yongjun; Huang, Chen; O, Wai-sum; Tang, Fai; Zhang, Jian V.

2013-01-01

15

LPS-induced TNF-? factor (LITAF)-deficient mice express reduced LPS-induced cytokine: Evidence for LITAF-dependent LPS signaling pathways  

PubMed Central

Previously we identified a transcription factor, LPS-Induced TNF-? Factor (LITAF), mediating inflammatory cytokine expression in LPS-induced processes. To characterize the role of LITAF in vivo, we generated a macrophage-specific LITAF-deficient mouse (macLITAF?/?). Our data demonstrate that in macrophages (i) several cytokines (such as TNF-?, IL-6, sTNF-RII, and CXCL16) are induced at lower levels in macLITAF?/? compared with LITAF+/+ control macrophages; (ii) macLITAF?/? mice are more resistant to LPS-induced lethality. To further identify LITAF signaling pathways, we tested mouse TLR-2?/?, -4?/?, and -9?/? and WT peritoneal macrophages exposed to LPS. Using these cells, we now show that LITAF expression can be induced after challenge either with LPS from Porphyromonas gingivalis via agonism at TLR-2, or with LPS from Escherichia coli via agonism at TLR-4, both requiring functional MyD88. We also show that, in response to LPS, the MyD88-dependent LITAF pathway differs from the NF-?B pathway. Furthermore, using a kinase array, p38? was found to mediate LITAF phosphorylation and the inhibition of p38? with a p38-specific inhibitor (SB203580) blocked LITAF nuclear translocation and reduced LPS-induced TNF-? protein levels. Finally, macLITAF?/? macrophages rescued by LITAF cDNA transfection restored levels of TNF-? similar to those observed in WT cells. We conclude that LITAF is an important mediator of the LPS-induced inflammatory response that can be distinguished from NF-?B pathway and that p38? is the specific kinase involved in the pathway linking LPS/MyD88/LITAF to TNF.

Tang, Xiaoren; Metzger, Daniel; Leeman, Susan; Amar, Salomon

2006-01-01

16

Fermented guava leaf extract inhibits LPS-induced COX-2 and iNOS expression in Mouse macrophage cells by inhibition of transcription factor NF-kappaB.  

PubMed

The goal of this study was to elucidate the antiinflammatory activities of Psidium guajava L. (guava) leaf. To improve the functionality of guava leaf, it was fermented with Phellinus linteus mycelia, Lactobacillus plantarum and Saccharomyces cerevisiae. The ethanol extract from fermented guava leaf inhibited lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin E(2) (PGE(2)) production. Western blot analysis showed that fermented guava leaf extract decreased LPS-induced inducible nitric oxide synthase (iNOS) and the cyclooxygenase-2 (COX-2) protein level in RAW 264.7 cells. To investigate the mechanism involved, the study examined the effect of fermented guava leaf extract on LPS-induced nuclear factor-kappaB (NF-kappaB) activation. Fermented guava leaf extract significantly inhibited LPS-induced NF-kappaB transcriptional activity. Immunochemical analysis revealed that fermented guava leaf extract suppressed LPS-induced degradation of I-kappaBalpha. Taken together, the data indicate that fermented guava leaf extract is involved in the inhibition of iNOS and COX-2 via the down-regulation of NF-kappaB pathway, revealing a partial molecular basis for the antiinflammatory properties of fermented guava leaf extract. PMID:18618521

Choi, Soo-Youn; Hwang, Joon-Ho; Park, Soo-Young; Jin, Yeong-Jun; Ko, Hee-Chul; Moon, Sang-Wook; Kim, Se-Jae

2008-08-01

17

Attenuation of lipopolysaccharide (LPS)-induced cytotoxicity by tocopherols and tocotrienols?  

PubMed Central

Lipopolysaccharide (LPS) induces host inflammatory responses and tissue injury and has been implicated in the pathogenesis of various age-related diseases such as acute respiratory distress syndrome, vascular diseases, and periodontal disease. Antioxidants, particularly vitamin E, have been shown to suppress oxidative stress induced by LPS, but the previous studies with different vitamin E isoforms gave inconsistent results. In the present study, the protective effects of ?- and ?-tocopherols and ?- and ?-tocotrienols on the oxidative stress induced by LPS against human lung carcinoma A549 cells were studied. They suppressed intracellular reactive oxygen formation, lipid peroxidation, induction of inflammatory mediator cytokines, and cell death. Tocopherols were incorporated into cultured cells much slower than tocotrienols but could suppress LPS-induced oxidative stress at much lower intracellular concentration than tocotrienols. Considering the bioavailability, it was concluded that ?-tocopherol may exhibit the highest protective capacity among the vitamin E isoforms against LPS-induced oxidative stress.

Nishio, Keiko; Horie, Masanori; Akazawa, Yoko; Shichiri, Mototada; Iwahashi, Hitoshi; Hagihara, Yoshihisa; Yoshida, Yasukazu; Niki, Etsuo

2013-01-01

18

Inhibitory effect of Buthus martensi Karsch extracts on interleukin-1?-induced expression of nitric oxide (NO) synthase and production of NO in human chondrocytes and LPS-induced NO and prostaglandin E2 production in mouse peritoneal macrophages  

Microsoft Academic Search

We examined the effect of Buthus martensi Karsch (BMK) extract on IL-1?-induced production of nitrogen oxide (NO) in primary human osteoarthritis (OA) chondrocytes. The cells were treated with BMK (10?g\\/ml) and IL-1? (2ng\\/ml) for different periods, and inducible nitric oxide synthase (iNOS) mRNA and protein expression were determined by real-time quantitative reverse transcriptase–polymerase chain reaction and Western blotting, respectively. The

Kap-Sung Kim; Hyun-Seok Cho; Seung-Deok Lee; Kyung-Ho Kim; Jae-Yong Cho; Kang-Hyun Chung; Young-Choon Lee; Sung-Kwon Moon; Cheorl-Ho Kim

2005-01-01

19

Protective effects of salidroside from Rhodiola rosea on LPS-induced acute lung injury in mice.  

PubMed

Salidroside is a major component extracted from Rhodiola rosea. In this study, we investigated protective effects of salidroside on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice. In the mouse model, we found that pretreatment with a single 120?mg/kg dose of salidroside prior to the administration of intratracheal LPS induced a significant decrease in the W/D ratio and mouse myeloperoxidase activity of lung, reduction protein concentration, the number of total cells, neutrophils and macrophages in the bronchoalveolar lavage fluid. In addition, salidroside also inhibited the production of several inflammatory cytokines, including tumor necrosis factor-?, interleukin-6 (IL-6) and IL-1?, and the NF-?B DNA-binding activation after LPS challenge. These results indicated that salidroside possess a protective effect on LPS-induced ALI in mice. PMID:22776035

Guan, Shuang; Xiong, Ying; Song, Bocui; Song, Yu; Wang, Dacheng; Chu, Xiao; Chen, Na; Huo, Meixia; Deng, Xuming; Lu, Jing

2012-08-01

20

Yohimbine Enhances Protection of Berberine against LPS-Induced Mouse Lethality through Multiple Mechanisms  

PubMed Central

Sepsis remains a major cause of mortality in intensive care units, better therapies are urgently needed. Gram-negative bacterial lipopolysaccharide (LPS) is an important trigger of sepsis. We have demonstrated that berberine (Ber) protects against lethality induced by LPS, which is enhanced by yohimbine (Y) pretreatment, and Ber combined with Y also improves survival in septic mice. However, the precise mechanisms by which Y enhances protection of Ber against LPS - induced lethality remain unclear. The present study confirmed that simultaneously administered Y also enhanced protection of Ber against LPS-induced lethality. Ber or/and Y attenuated liver injury, but not renal injury in LPS-challenged mice. Ber or/and Y all inhibited LPS-stimulated I?B?, JNK and ERK phosphorylation, NF-?B activation as well as TNF-? production. Ber also increased IL-10 production in LPS-challenged mice, which was enhanced by Y. Furthermore, Ber or/and Y all suppressed LPS-induced IRF3, TyK2 and STAT1 phosphorylation, as well as IFN-? and IP-10 mRNA expression in spleen of mice at 1 h after LPS challenge. Especially, Y enhanced the inhibitory effect of Ber on LPS-induced IP-10 mRNA expression. In vitro experiments further demonstrated that Y significantly enhanced the inhibitory effect of Ber on TNF-? production in LPS-treated peritoneal macrophages, Ber combined with Y promoted LPS-induced IL-10 production and LPS-stimulated I?B?, JNK, ERK and IRF3 phosphorylation and NF-?B activation were also suppressed by Ber or/and Y pretreatment in peritoneal macrophages. Taken together, these results demonstrate that Y enhances the protection of Ber against LPS-induced lethality in mice via attenuating liver injury, upregulating IL-10 production and suppressing I?B?, JNK, ERK and IRF3 phosphorylation. Ber combined with Y may be an effective immunomodulator agent for the prevention of sepsis.

Zhang, Haoqing; Jia, Baoyin; Wang, Daan; Li, Hongmei; Lu, Daxiang; Qi, Renbin; Yan, Yuxia; Wang, Huadong

2012-01-01

21

Yohimbine enhances protection of berberine against LPS-induced mouse lethality through multiple mechanisms.  

PubMed

Sepsis remains a major cause of mortality in intensive care units, better therapies are urgently needed. Gram-negative bacterial lipopolysaccharide (LPS) is an important trigger of sepsis. We have demonstrated that berberine (Ber) protects against lethality induced by LPS, which is enhanced by yohimbine (Y) pretreatment, and Ber combined with Y also improves survival in septic mice. However, the precise mechanisms by which Y enhances protection of Ber against LPS-induced lethality remain unclear. The present study confirmed that simultaneously administered Y also enhanced protection of Ber against LPS-induced lethality. Ber or/and Y attenuated liver injury, but not renal injury in LPS-challenged mice. Ber or/and Y all inhibited LPS-stimulated I?B?, JNK and ERK phosphorylation, NF-?B activation as well as TNF-? production. Ber also increased IL-10 production in LPS-challenged mice, which was enhanced by Y. Furthermore, Ber or/and Y all suppressed LPS-induced IRF3, TyK2 and STAT1 phosphorylation, as well as IFN-? and IP-10 mRNA expression in spleen of mice at 1 h after LPS challenge. Especially, Y enhanced the inhibitory effect of Ber on LPS-induced IP-10 mRNA expression. In vitro experiments further demonstrated that Y significantly enhanced the inhibitory effect of Ber on TNF-? production in LPS-treated peritoneal macrophages, Ber combined with Y promoted LPS-induced IL-10 production and LPS-stimulated I?B?, JNK, ERK and IRF3 phosphorylation and NF-?B activation were also suppressed by Ber or/and Y pretreatment in peritoneal macrophages. Taken together, these results demonstrate that Y enhances the protection of Ber against LPS-induced lethality in mice via attenuating liver injury, upregulating IL-10 production and suppressing I?B?, JNK, ERK and IRF3 phosphorylation. Ber combined with Y may be an effective immunomodulator agent for the prevention of sepsis. PMID:23285207

Li, Hui; Wang, Yiyang; Zhang, Haoqing; Jia, Baoyin; Wang, Daan; Li, Hongmei; Lu, Daxiang; Qi, Renbin; Yan, Yuxia; Wang, Huadong

2012-12-28

22

ATF3 Protects against LPS-Induced Inflammation in Mice via Inhibiting HMGB1 Expression  

PubMed Central

Lipopolysaccharide (LPS) triggers innate immunity mainly via TLR4 signaling. ATF3 is a negative regulator of TLR4 signaling. HMGB1 plays a critical role in the final step of sepsis. However, the mechanisms of ATF3 and the role of HMGB1 in regulating innate immunity-induced sepsis are incompletely understood. In this study, we found that serum HMGB1 levels were 10-fold higher in patients with sepsis than normal controls. We further demonstrated that ATF3 gene knockout in mice subjected to LPS-induced endotoxemia correlates with an increase in the mortality rate and the elevated expression of IL-6, TNF-?, NO, MCP-1, and HMGB1 in the lung tissues or serum. The biochemical effects of ATF3 were observed in in vitro macrophages and blocked by ATF3 siRNA treatment. We have also shown that adeno-associated virus-mediated ATF3 gene transfer protected ATF3 knockout mice from LPS-induced mortality. In addition, ATF3 knockdown increased LPS-induced release of HMGB1. In conclusion, upregulation of ATF3 contributes to the reduced release of inflammatory molecules, especially HMGB1, which induced lung injury and increased the survival rate of mice after LPS challenge. Therefore, suppressing LPS-induced inflammation with ATF3 induction or ATF3 mimetics may be an important strategy for sepsis therapy.

Lai, Pei-Fang; Cheng, Ching-Feng; Lin, Heng; Tseng, Tzu-Ling; Chen, Hsi-Hsien; Chen, Sung-Ho

2013-01-01

23

Apoptotic cells inhibit LPS-induced cytokine and chemokine production and IFN responses in macrophages  

PubMed Central

Apoptosis is a critical process in tissue homeostasis and results in immediate removal of the dying cell by professional phagocytes such as macrophages and dendritic cells. Phagocytosis of apoptotic cells actively suppresses production of pro-inflammatory growth factors and cytokines. Impaired phagocytosis of apoptotic cells has been implicated in the pathogenesis of chronic inflammatory and autoimmune diseases. In this study we found that, in addition to suppressing LPS-induced production of TNF-? and IL-6, phagocytosis of apoptotic cells by macrophages suppressed production of the chemokine CXCL10 that is activated by LPS-induced autocrine-acting type I IFNs. Inhibition of cytokine and chemokine production was not universally affected since LPS-induced production of IL-10 and IL-8 was not significantly affected. Apoptotic cells had minimal effects on LPS-induced activation of NF-?B and MAPKs, but induced expression of SOCS proteins and substantially suppressed induction of CXCL10 expression by IFN-?. In addition to suppressing LPS responses, apoptotic cells inhibited macrophage responses to another major macrophage activator IFN-? by attenuating IFN-?-induced STAT1 activation and downstream gene expression. These results identify suppressive effects of apoptotic cells on signal transduction, and extend our understanding of the anti-inflammatory effects of apoptotic cells to include suppression of Jak-STAT signaling.

Tassiulas, Ioannis; Park-Min, Kyung-Hyun; Hu, Yang; Kellerman, Lisa; Mevorach, Dror; Ivashkiv, Lionel B.

2009-01-01

24

Resveratrol inhibits LPS-induced epithelial-mesenchymal transition in mouse melanoma model.  

PubMed

Epithelial to mesenchymal transition (EMT) has been linked to metastasis. Resveratrol exhibits potential antitumor activities; however, the inhibitory effects of resveratrol on the EMT of melanoma have not been demonstrated. Here, a new role for LPS in promoting EMT is described. LPS-induced EMT was identified by examining the markers of EMT. To assess the activation of NF-?B signal transduction pathway, we performed a reporter assay by using tumor cells transfected with the luciferase gene under the control of NF-?B response elements. The antitumor effects of resveratrol were evaluated in an experimental mouse metastasis tumor model. LPS increased N-cadherin and Snail expression and decreased zonula occludens-1 expression in a dose- and time-dependent manner. Meanwhile, LPS stimulated cell migration through activation of TLR4/NF-?B signal pathway. LPS-induced EMT is critical for inflammation-initiated metastasis. Nuclear translocation and transcriptional activity of p65 NF-?B, an important inducer of EMT, were inhibited by resveratrol. Resveratrol inhibited LPS-induced tumor migration and markers of EMT, significantly prolonged animal survival and reduced the tumor size. Thus, resveratrol plays an important role in the inhibition of LPS-induced EMT in mouse melanoma through the down-regulation of NF-?B activity. The data provide an insight into the mechanisms on the function of resveratrol during the processes of EMT. PMID:22344225

Chen, Man-Chin; Chang, Wen-Wei; Kuan, Yu-Diao; Lin, Song-Tao; Hsu, Hui-Chun; Lee, Che-Hsin

2012-02-16

25

Phenidone protects the nigral dopaminergic neurons from LPS-induced neurotoxicity.  

PubMed

Anti-inflammatory drugs such as ibuprofen appear to prevent the development of Parkinson's disease (PD); however, long-term use has undesirable side-effects. A new strategy for anti-inflammatory drug therapy is using a dual inhibitor of COX and lipooxygenase (LOX). Here, we compared the dopaminergic neuroprotective property of phenidone (a dual COX and LOX inhibitor) with COX or LOX inhibitors including SC-560 (a COX-1 inhibitor), aspirin (a COX-1/2 inhibitor), meloxicam (a preferential COX-2 inhibitor), caffeic acid (a 5-LOX inhibitor), and esculetin (a 5, 12-LOX inhibitor) in our lipopolysaccharide (LPS)-induced PD animal model. Our results show that COX-2 and 5-LOX play a major role in LPS-induced dopaminergic neurotoxicity, as meloxicam and phenidone attenuated LPS-induced oxidative stress and meloxicam, phenidone, and caffeic acid attenuated dopaminergic neurodegeneration, while SC-560, aspirin, and esculetin did not. In addition, phenidone was superior in attenuating LPS-induced dopaminergic neurodegeneration and microglia activation, probably as a result of dual inhibition of COX-2 and LOX. Therefore, dual inhibition of COX and LOX with phenidone represents a promising new candidate for anti-inflammatory drug therapy, and may provide a novel therapeutic approach for inflammation-related neurodegenerative diseases including PD. PMID:18760329

Li, Zhengyi; Choi, Dong-Young; Shin, Eun-Joo; Hunter, Randy L; Jin, Chun Hui; Wie, Myung-Bok; Kim, Min Soo; Park, Seok Joo; Bing, Guoying; Kim, Hyoung-Chun

2008-08-22

26

NEUTROPHILS PLAY A CRITICAL ROLE IN THE DEVELOPMENT OF LPS-INDUCED AIRWAY DISEASE  

EPA Science Inventory

ETD-02-045 (GAVETT) GPRA # 10108 Neutrophils Play a Critical Role in the Development of LPS-Induced Airway Disease. Jordan D. Savov, Stephen H. Gavett*, David M. Brass, Daniel L. Costa*, and David A. Schwartz ABSTRACT We investigated the role of neutrophils...

27

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...

28

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.

Sender, Vicky; Lang, Linda; Stamme, Cordula

2013-01-01

29

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

2012-12-28

30

Effects of cannabinoid receptor ligands on LPS-induced pulmonary inflammation in mice  

Microsoft Academic Search

The effects of cannabinoid receptor agonists WIN 55,212-2, ?9-tetrahydrocannabinol (?9-THC), arachidonoylethanolamide (anandamide) and palmitoylethanolamide on lipopolysaccharide (LPS) -induced bronchopulmonary inflammation in mice were investigated. WIN 55,212-2 and ?9-THC induced a concentration-dependent decrease in TNF-? level in the bronchoalveolar lavage fluid (BALF) (maximum inhibition 52.7% and 36.9% for intranasal doses of 750 nmol.kg?1 and 2.65 mmol.kg?1, respectively). This effect was accompanied

E. Berdyshev; E. Boichot; M. Corbel; N. Germain; V Lagente

1998-01-01

31

LPS induces phosphorylation of actin-regulatory proteins leading to actin reassembly and macrophage motility.  

PubMed

Upon bacterial infection lipopolysaccharide (LPS) induces migration of monocytes/macrophages to the invaded region and production of pro-inflammatory mediators. We examined mechanisms of LPS-stimulated motility and found that LPS at 100?ng/ml induced rapid elongation and ruffling of macrophage-like J774 cells. A wound-healing assay revealed that LPS also activated directed cell movement that was followed by TNF-? production. The CD14 and TLR4 receptors of LPS translocated to the leading lamella of polarized cells, where they transiently colocalized triggering local accumulation of actin filaments and phosphatidylinositol 4,5-bisphosphate. Fractionation of Triton X-100 cell lysates revealed that LPS induced polymerization of cytoskeletal actin filaments by 50%, which coincided with the peak of cell motility. This microfilament population appeared at the expense of short filaments composing the plasma membrane skeleton of unstimulated cells and actin monomers consisting prior to the LPS stimulation about 60% of cellular actin. Simultaneously with actin polymerization, LPS stimulated phosphorylation of two actin-regulatory proteins, paxillin on tyrosine 118 by 80% and N-WASP on serine 484/485 by 20%, and these events preceded activation of NF-?B. LPS-induced protein phosphorylation and reorganization of the actin cytoskeleton were inhibited by PP2, a drug affecting activity of tyrosine kinases of the Src family. The data indicate that paxillin and N-WASP are involved in the reorganization of actin cytoskeleton driving motility of LPS-stimulated cells. Disturbances of actin organization induced by cytochalasin D did not inhibit TNF-? production suggesting that LPS-induced cell motility is not required for TNF-? release. PMID:21898535

Kleveta, Galyna; Borz?cka, Kinga; Zdioruk, Mykola; Czerkies, Maciej; Kuberczyk, Hanna; Sybirna, Natalia; Sobota, Andrzej; Kwiatkowska, Katarzyna

2012-01-01

32

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.

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

2009-01-01

33

Granulocytes enhance LPS-induced tissue factor activity in monocytes via an interaction with platelets  

Microsoft Academic Search

In the present study we have investigated the effect of platelets and granulocytes on bacterial lipopoly- saccharide (LPS)-induccd tissue factor (TF) activity in monocytes. Experiments were performed on freshly iso- lated cells resuspended in heparinized plasma and recom- bined with platelet-poor or platelet-rich plasma. In a platelet-dependent reaction the granulocytes enhanced LPS-induced TF activity by an average of 100%. The

Hanne Halvorsen; Jan Ole Olsen

34

Minocycline attenuates lipopolysaccharide (LPS)-induced neuroinflammation, sickness behavior, and anhedonia  

Microsoft Academic Search

BACKGROUND: Activation of the peripheral innate immune system stimulates the secretion of CNS cytokines that modulate the behavioral symptoms of sickness. Excessive production of cytokines by microglia, however, may cause long-lasting behavioral and cognitive complications. The purpose of this study was to determine if minocycline, an anti-inflammatory agent and purported microglial inhibitor, attenuates lipopolysaccharide (LPS)-induced neuroinflammation, sickness behavior, and anhedonia.

Christopher J Henry; Yan Huang; Angela Wynne; Mark Hanke; Justin Himler; Michael T Bailey; John F Sheridan; Jonathan P Godbout

2008-01-01

35

Alcohol exacerbates LPS-induced fibrosis in subclinical acute pancreatitis.  

PubMed

The role of pancreatic acinar cells in initiating fibrogenic responses during the early stages of alcoholic acute pancreatitis has not been evaluated. We investigated the ability of injured acinar cells to generate pancreatic fibrosis in acute pancreatitis. Rats were fed either an ethanol-containing or control diet over 14 weeks and euthanized 3 or 24 hours after a single lipopolysaccharide injection. Profibrotic transforming growth factor-? of acinar cells and pancreatic fibrosis were assessed by immunofluorescence, histological characteristics, and electron microscopy. Human pancreatic tissues were also evaluated. Periacinar cell fibrosis and collagen were exacerbated 24 hours after endotoxemia in alcohol-fed rats. Alcohol exposure exacerbated acinar cell-specific production of transforming growth factor ? in response to lipopolysaccharide in vivo and in acinar cell-like AR42J cells in vitro. Although a morphological examination showed no visible signs of necrosis, early pancreatic fibrosis can be initiated by little or no pancreatic necrosis. Transforming growth factor ? was also significantly increased in human acinar cells from patients with acute/recurrent pancreatitis compared with chronic pancreatitis tissue. Alcohol exacerbates lipopolysaccharide-induced pancreatic fibrosis during the early onset of mild, subclinical, acute pancreatitis. We suggest that multiple, subclinical, acute pancreatitis episodes can accumulate in fibrosis during the development of chronic pancreatitis, even if there is no history of acute pancreatitis. PMID:24091223

Gu, Haitao; Fortunato, Franco; Bergmann, Frank; Büchler, Markus W; Whitcomb, David C; Werner, Jens

2013-09-30

36

Effect of Tetrandrine on LPS-induced NF-?B activation in isolated pancreatic acinar cells of rat  

Microsoft Academic Search

AIM: To investigate the effect of Tetrandrine (Tet) on LPS-induced NF-?B activation and cell injury in pancre- atic acinar cells and to explore the mechanism of Tetran- drine preventing LPS-induced acinar cell injury. METHODS: Male rat pancreatic acinar cells were iso- lated by collagenase digestion, then exposed to LPS (10 mg\\/L), Tet (50 ?mol\\/L, 100 ?mol\\/L) or normal media. At

Hong Zhang; Yong-Yu Li; Xian-Zhong Wu

37

Molecular Hydrogen Reduces LPS-Induced Neuroinflammation and Promotes Recovery from Sickness Behaviour in Mice  

PubMed Central

Molecular hydrogen has been shown to have neuroprotective effects in mouse models of acute neurodegeneration. The effect was suggested to be mediated by its free-radical scavenger properties. However, it has been shown recently that molecular hydrogen alters gene expression and protein phosphorylation. The aim of this study was to test whether chronic ad libitum consumption of molecular hydrogen-enriched electrochemically reduced water (H-ERW) improves the outcome of lipopolysaccharide (LPS)-induced neuroinflammation. Seven days after the initiation of H-ERW treatment, C57Bl/6 mice received a single injection of LPS (0.33 mg/kg i.p.) or an equivalent volume of vehicle. The LPS-induced sickness behaviour was assessed 2 h after the injection, and recovery was assessed by monitoring the spontaneous locomotor activity in the homecage for 72 h after the administration of LPS. The mice were killed in the acute or recovery phase, and the expression of pro- and antiinflammatory cytokines in the hippocampus was assessed by real-time PCR. We found that molecular hydrogen reduces the LPS-induced sickness behaviour and promotes recovery. These effects are associated with a shift towards anti-inflammatory gene expression profile at baseline (downregulation of TNF- ? and upregulation of IL-10). In addition, molecular hydrogen increases the amplitude, but shortens the duration and promotes the extinction of neuroinflammation. Consistently, molecular hydrogen modulates the activation and gene expression in a similar fashion in immortalized murine microglia (BV-2 cell line), suggesting that the effects observed in vivo may involve the modulation of microglial activation. Taken together, our data point to the regulation of cytokine expression being an additional critical mechanism underlying the beneficial effects of molecular hydrogen.

Spulber, Stefan; Edoff, Karin; Hong, Lie; Morisawa, Shinkatsu; Shirahata, Sanetaka; Ceccatelli, Sandra

2012-01-01

38

Adenosine receptor A3 is a critical mediator in LPS-induced pulmonary inflammation.  

PubMed

Adenosine receptor A(3) (A(3)) regulates directed movement of polymorphonuclear cells (PMNs) to sites of inflammation and has been implicated as a relevant mediator in models of inflammatory diseases. Here, we sought to characterize the role of A(3) in a murine model of lung inflammation. Initial studies revealed that pulmonary A(3) transcript levels were elevated following LPS exposure in vivo. In addition, inhalation of LPS increased the accumulation of PMNs in wild-type and A(3)(-/-) mice in all lung compartments. Pretreatment with the specific A(3)-agonist Cl-IB-MECA significantly decreased migration of PMNs into lung interstitium and alveolar air space of wild-type mice but not of A(3)(-/-) mice. Lower PMN counts were associated with reduced levels of TNF-? and IL-6 in the alveolar space of wild-type mice that received Cl-IB-MECA. In addition, Cl-IB-MECA attenuated LPS-induced microvascular permeability in wild-type mice as assessed by the extravasation of Evans blue. In pulmonary microvascular endothelial cells, Cl-IB-MECA reduced LPS-induced cytoskeletal remodeling and cell retraction, consistent with a specific role of A(3) for maintaining endothelial integrity. Migratory activity of human PMNs across an endothelial or epithelial monolayer was reduced when A(3) was activated on PMNs. Studies in chimeric mice, however, revealed that Cl-IB-MECA required A(3) on both hematopoietic and nonhematopoietic cells to reduce transmigration in vivo. Together, our results shed new light on the role of A(3) in LPS-induced PMN trafficking in the lung and suggest pharmacological modulation of A(3)-dependent pathways as a promising approach in lung inflammation. PMID:20639349

Wagner, Rosalyn; Ngamsri, Kristian-Christos; Stark, Stefanie; Vollmer, Irene; Reutershan, Jörg

2010-07-16

39

Octreotide regulates CC but not CXC LPS-induced chemokine secretion in rat Kupffer cells  

PubMed Central

Kupffer cells (KC) and lipopolysaccharide (LPS) interaction is the initial event leading to hepatic inflammation and fibrosis in many types of liver injury. We studied chemokine secretion by KC activated with LPS and the possible effect of the somatostatin analogue octreotide, in the regulation of this process. KC isolated from Sprague–Dawley rats were cultured in the presence of LPS added alone or with different concentrations of octreotide for 24 and 48 h, and chemokine production was assessed in culture supernatants by ELISA. CC chemokine mRNA expression was assessed by semiquantitative RT–PCR. Vehicle-stimulated KC produced a basal amount of CC and CXC chemokines. LPS-stimulated KC secreted significantly increased amounts of IL-8 (GRO/CINC-1) (P<0.001), MIP-2 (P<0.001), MCP-1 (P<0.001), and RANTES (P<0.01). Octreotide inhibited LPS-induced secretion of the CC chemokines MCP-1 (P<0.05) and RANTES (P<0.05), but not the CXC chemokines IL-8 (GRO/CINC-1) and MIP-2, in a concentration-dependent manner. Downregulation of basal and LPS-induced mRNA expression of the CC chemokines was also observed in the presence of octreotide. Pretreatment with phosphatidylinositol 3 (PI3)-kinase inhibitors reduced chemokine production by LPS-treated KC in both the mRNA and protein level. Furthermore, it prevented the octreotide inhibitory effect on LPS-induced chemokine secretion, indicating a possible involvement of the PI3-kinase pathway. In conclusion, these data demonstrate that chemokine secretion by KC can be differentially regulated by octreotide, and suggest that this somatostatin analogue may have immunoregulatory effects on resident liver macrophages.

Valatas, Vassilis; Kolios, George; Manousou, Pinelopi; Notas, George; Xidakis, Costas; Diamantis, Ioannis; Kouroumalis, Elias

2004-01-01

40

Antiinflammatory effects of etoricoxib alone and combined with NSAIDs in LPS-induced reactive arthritis  

Microsoft Academic Search

.\\u000a Objective:  Nonsteroidal anti-inflammatory drugs constitute the primary therapeutic approach in reactive arthritis. Here, we compared\\u000a etoricoxib, a specific COX-2 inhibitor, with other cyclooxygenase inhibitors on articular incapacitation, edema, leukocyte\\u000a migration, and gastric damage, in a model of LPS-induced reactive arthritis in rats.\\u000a \\u000a \\u000a \\u000a Methods:  E. coli Lipopolysaccharide was injected into a carrageenan-primed knee-joint of rats. The effects of etoricoxib, piroxicam,\\u000a indomethacin, as

E. Bressan; C. R. Tonussi

2008-01-01

41

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.

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

2009-01-01

42

Yohimbine promotes cardiac NE release and prevents LPS-induced cardiac dysfunction via blockade of presynaptic ?2A-adrenergic receptor.  

PubMed

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

2013-05-14

43

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.

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

2013-01-01

44

A1 and A3 adenosine receptors inhibit LPS-induced hypoxia-inducible factor-1 accumulation in murine astrocytes.  

PubMed

Adenosine (Ado) exerts neuroprotective and anti-inflammatory functions by acting through four receptor subtypes A1, A2A, A2B and A3. Astrocytes are one of its targets in the central nervous system. Hypoxia-inducible factor-1 (HIF-1), a master regulator of oxygen homeostasis, is induced after hypoxia, ischemia and inflammation and plays an important role in brain injury. HIF-1 is expressed by astrocytes, however the regulatory role played by Ado on HIF-1? modulation induced by inflammatory and hypoxic conditions has not been investigated. Primary murine astrocytes were activated with lipopolysaccharide (LPS) with or without Ado, Ado receptor agonists, antagonists and receptor silencing, before exposure to normoxia or hypoxia. HIF-1? accumulation and downstream genes regulation were determined. Ado inhibited LPS-increased HIF-1? accumulation under both normoxic and hypoxic conditions, through activation of A1 and A3 receptors. In cells incubated with the blockers of p44/42 MAPK and Akt, LPS-induced HIF-1? accumulation was significantly decreased in normoxia and hypoxia, suggesting the involvement of p44/42 MAPK and Akt in this effect and Ado inhibited kinases phosphorylation. A series of angiogenesis and metabolism related genes were modulated by hypoxia in an HIF-1 dependent way, but not further increased by LPS, with the exception of GLUT-1 and hexochinase II that were elevated by LPS only in normoxia and inhibited by Ado receptors. Instead, genes involved in inflammation, like inducible nitric-oxide synthase (iNOS) and A2B receptors, were increased by LPS in normoxia, strongly stimulated by LPS in concert with hypoxia and inhibited by Ado, through A1 and A3 receptor subtypes. In conclusion A1 and A3 receptors reduce the LPS-mediated HIF-1? accumulation in murine astrocytes, resulting in a downregulation of genes involved in inflammation and hypoxic injury, like iNOS and A2B receptors, in both normoxic and hypoxic conditions. PMID:23969284

Gessi, Stefania; Merighi, Stefania; Stefanelli, Angela; Fazzi, Debora; Varani, Katia; Borea, Pier Andrea

2013-08-19

45

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

46

Protective effects of early treatment with lipoic acid in LPS-induced lung injury in rats.  

PubMed

A lipopolysaccharide (LPS) stimulates the synthesis and releases several metabolites from phagocytes which can lead to an endotoxic shock characterized by multiple organ injury with the earliest to occur in the lungs. Among LPS-induced metabolites, reactive oxygen species are considered to play a crucial pathogenetic role in the lung damage. In this study, the effect of early administration of an antioxidant, alpha-lipoic acid (LA), on pulmonary lipid peroxidation, lung hydrogen peroxide (H(2)O(2)) concentration, and lung sulfhydryl group content was evaluated in rats with endotoxic shock induced by administration of LPS (Escherichia coli 026:B6, 30 mg/kg, i.v.). In addition, lung edema was assessed with wet-to-dry lung weight (W/D) ratio. Animals were treated intravenously with normal saline or LA 60 mg/kg or 100 mg/kg 30 min after LPS injection. After a 5 h observation, animals were killed and the lungs were isolated for measurements. Injection of LPS alone resulted in the development of shock and oxidative stress, the latter indicated by a significant increase in the lung thiobarbituric acid reacting substances (TBARS) and H(2)O(2) concentrations, and a decrease in the lung sulfhydryl group content. The increase in the W/D ratio after the LPS challenge indicated the development of lung edema in response to LPS. Administration of LA after the LPS challenge resulted in an increase in the sulfhydryl group content and a decrease in TBARS and H202 concentration in the lungs as compared with the LPS group. An insignificant decrease in the W/D ratio was observed in rats treated with either dose of LA. These results indicate that the LPS-induced oxidative lung injury in endotoxic rats can be attenuated by early treatment with LA. Administration of LA could be a useful adjunct to conventional approach in the management of septic shock. PMID:17928649

Goraca, A; Józefowicz-Okonkwo, G

2007-09-01

47

Inhibitory effects of sulfated 20(S)-ginsenoside Rh2 on the release of pro-inflammatory mediators in LPS-induced RAW 264.7 cells.  

PubMed

Ginsenoside Rh2 is one of the most important ginsenosides in ginseng with anti-inflammatory and antitumor effects. However, the extremely poor oral bioavailability induced by its low water solubility greatly limits the potency of Rh2 in vivo. In the previous study, we sulfated 20(S)-ginsenoside Rh2 with chlorosulfonic acid and pyridine method, and got one novel derivative, Rh2-B1, with higher water solubility and greater immunologic enhancement than Rh2. However, the anti-inflammatory effect of Rh2-B1 remains unclear. We therefore investigated the effects of Rh2-B1 on lipopolysaccharide (LPS)-induced proinflammatory mediators in RAW 264.7 macrophages. We found that Rh2-B1 dramatically inhibited LPS-induced overproduction of nitric oxide, prostaglandin E2, tumor necrosis factor (TNF)-?, interleukin (IL)-1?, and IL-6. Consistently, the protein and mRNA expression levels of inducible nitric oxide synthase and cyclooxygenase-2 were remarkably decreased by Rh2-B1. In addition, Rh2-B1 significantly suppressed the phosphorylations of p38, c-Jun N-terminal kinase, and extracellular signal receptor-activated kinase 1/2 induced by LPS. Rh2-B1 was further shown to inhibit NF-?B p65 translocation into the nucleus by suppressing I?B? degradation. In conclusion, we demonstrate that Rh2-B1 inhibits the release of LPS-induced pro-inflammatory mediators through blocking mitogen-activated protein kinases and NF-?B signaling pathways, suggesting that sulfated ginsenosides could be potential agents for anti-inflammatory therapies. PMID:23665488

Yi, Peng-Fei; Bi, Wen-Yan; Shen, Hai-Qing; Wei, Qian; Zhang, Li-Yan; Dong, Hai-Bing; Bai, Huan-Li; Zhang, Cui; Song, Zhou; Qin, Qian-Qian; Lv, Shuang; Wu, Shuai-Cheng; Fu, Ben-Dong; Wei, Xu-Bin

2013-05-09

48

PECAM-1 dampens cytokine levels during LPS-induced endotoxemia by regulating leukocyte trafficking  

PubMed Central

Aims To investigate the mechanism by which platelet endothelial cell adhesion molecule 1 (PECAM-1/CD31), an immunoglobulin (Ig)-superfamily cell adhesion and signaling receptor, regulates pro-inflammatory cytokine levels. The purpose of the present investigation was to test the hypothesis that PECAM-1 influences circulating cytokine levels by regulating the trafficking of activated, cytokine-producing leukocytes to sites of inflammation. Main methods PECAM-1+/+ and PECAM-1?/? mice were subjected to lipopolysaccharide (LPS)-induced endotoxemia, and systemic cytokine levels were measured by Bioplex multiplex cytokine assays. Flow cytometry was employed to enumerate leukocytes at inflammatory sites and to measure cytokine synthesis in leukocyte sub-populations. Enzyme-linked immunosorbent assay (ELISA) was used to measure cytokine levels in tissue samples and in supernatants of in vitro-stimulated leukocytes. Key findings We confirmed earlier reports that mice deficient in PECAM-1 had greater systemic levels of pro-inflammatory cytokines following intraperitoneal (IP) LPS administration. Interestingly, expression of PECAM-1, in mice, had negligible effects on the level of cytokine synthesis by leukocytes stimulated in vitro with LPS and in peritoneal macrophages isolated from LPS-injected mice. There was, however, excessive accumulation of macrophages and neutrophils in the lungs of PECAM-1-deficient, compared with wild-type, mice - an event that correlated with a prolonged increase in lung pro-inflammatory cytokine levels. Significance Our results demonstrate that PECAM-1 normally functions to dampen systemic cytokine levels during LPS-induced endotoxemia by diminishing the accumulation of cytokine-producing leukocytes at sites of inflammation, rather than by modulating cytokine synthesis by leukocytes.

Privratsky, Jamie R.; Tilkens, Sarah B.; Newman, Debra K.; Newman, Peter J.

2011-01-01

49

Immunomodulatory effects of thalidomide analogs on LPS-induced plasma and hepatic cytokines in the rat.  

PubMed

Thalidomide has shown to inhibit, selectively and mainly the cytokine tumor necrosis factor-alpha (TNF-alpha), thus, thalidomide has inhibitory consequences on other cytokines; this is ascribed as an immunomodulatory effect. Novel thalidomide analogs are reported with immunomodulatory activity. The aim of this work was to synthesize some of these analogs and to assess them as immunomodulatory agents in an acute model of LPS-induced septic challenge in rat. Animal groups received orally twice a day vehicle carboxymethylcellulose (0.9%), or thalidomide in suspension (100mg/kg), or analogs in an equimolar dose. Two hours after last dose, rats were injected with saline (NaCl, 0.9%, i.p.) or LPS (5mg/kg, i.p.). Groups were sacrificed 2h after injection and samples of blood and liver were obtained. TNF-alpha, interleukin-6, -1beta, and -10 (IL-6, IL-1beta, IL-10) were quantified by enzyme linked immunosorbent assay (ELISA) and studied in plasma and liver. After 2h of LPS-induction, different patterns of measured cytokines were observed with thalidomide analogs administration evidencing their immunomodulatory effects. Interestingly, some analogs decreased significantly plasma and hepatic levels of LPS-induced proinflammatory TNF-alpha and others increased plasma concentration of anti-inflammatory IL-10. Thalidomide analogs also showed slight effects on the remaining proinflammatory cytokines. Differences among immunomodulatory effects of analogs can be related to potency, mechanism of action, and half lives. Thalidomide analogs could be used as a pharmacological tool and in therapeutics in the future. PMID:15345321

Fernández-Martínez, Eduardo; Morales-Ríos, Martha S; Pérez-Alvarez, Víctor; Muriel, Pablo

2004-10-01

50

Suppressing LPS-induced early signal transduction in macrophages by a polyphenol degradation product: a critical role of MKP-1.  

PubMed

Macrophages represent the first defense line against bacterial infection and therefore, play a crucial role in early inflammatory response. In this study, we investigated the role of MAPKs and MKP-1 activation in regulation of an early inflammatory response in RAW 264.7 macrophage cells. We induced the inflammatory response by treating the macrophages with LPS and inhibited an early inflammatory response by using ferulaldehyde, a water-soluble end-product of dietary polyphenol degradation that we found previously to exert its beneficial anti-inflammatory effects during the early phase of in vivo inflammation. We found that LPS-induced ROS and nitrogen species formations were reduced by ferulaldehyde in a concentration-dependent manner, and ferulaldehyde protected mitochondria against LPS-induced rapid and massive membrane depolarization. LPS induced early suppression of MKP-1, which was accompanied by activation of JNK, ERK, and p38 MAPK. By reversing LPS-induced early suppression of MKP-1, ferulaldehyde diminished MAPK activation, thereby inhibiting NF-?B activation, mitochondrial depolarization, and ROS production. Taken together, our data suggest that ferulaldehyde exerts its early anti-inflammatory effect by preserving the mitochondrial membrane integrity and shifting the expression of MKP-1 forward in time in macrophages. PMID:20884647

Tucsek, Zsuzsanna; Radnai, Balazs; Racz, Boglarka; Debreceni, Balazs; Priber, Janos K; Dolowschiak, Tamas; Palkovics, Tamas; Gallyas, Ferenc; Sumegi, Balazs; Veres, Balazs

2010-09-30

51

TNF-alpha tolerance blocks LPS-induced hypophagia but LPS tolerance fails to prevent TNF-alpha-induced hypophagia.  

PubMed

To investigate the role of tumor necrosis factor-alpha (TNF-alpha) in bacterial lipopolysaccharide (LPS)-induced hypophagia, we tested whether a cross tolerance between LPS and TNF-alpha exists with respect to their anorectic effects. Only the first of three subsequent intraperitoneal injections of LPS (100 micrograms/kg body wt) given every second day at dark onset (12:12-h light-dark cycle) led to a significant reduction of food intake in male rats. Likewise, intraperitoneal injections of human recombinant TNF-alpha (150 micrograms > or = 3 x 10(6) U/kg body wt) also resulted in tolerance to its hypophagic effect. LPS tolerance did not alter the hypophagic response to subsequently injected TNF-alpha (n = 14). However, TNF-alpha pretreatment completely blocked the hypophagic response to LPS (n = 14). The results demonstrate that tolerance to the hypophagic effect of exogenous TNF-alpha is sufficient to eliminate LPS-induced hypophagia. This is consistent with the hypothesis that endogenous TNF-alpha plays a major role in LPS-induced hypophagia. The ineffectiveness of LPS tolerance to attenuate TNF-alpha-induced hypophagia is compatible with findings demonstrating that reduced TNF-alpha production is an important feature of LPS tolerance. PMID:9530241

Porter, M H; Arnold, M; Langhans, W

1998-03-01

52

Moringa Fruit Inhibits LPS-Induced NO / iNOS Expression through Suppressing the NF -? B Activation in RAW264.7 Cells.  

PubMed

In this study, we evaluated the anti-inflammatory effects of moringa (Moringa oleifera Lam.), a natural biologically active substance, by determining its inhibitory effects on pro-inflammatory mediators in lipopolysaccharide (LPS)-stimulated macrophage RAW264.7 cells. Extracts from different parts of moringa (root, leaf, and fruit) reduced LPS-induced nitric oxide (NO) release in a dose-dependent manner. The moringa fruit extract most effectively inhibited LPS-induced NO production and levels of inducible nitric oxide synthase (iNOS). The moringa fruit extract also was shown to suppress the production of inflammatory cytokines including IL-1?, TNF-?, and IL-6. Furthermore, moringa fruit extract inhibited the cytoplasmic degradation of I ? B -? and the nuclear translocation of p65 proteins, resulting in lower levels of NF -? B transactivation. Collectively, the results of this study demonstrate that moringa fruit extract reduces the levels of pro-inflammatory mediators including NO , IL-1?, TNF-?, and IL-6 via the inhibition of NF -? B activation in RAW264.7 cells. These findings reveal, in part, the molecular basis underlying the anti-inflammatory properties of moringa fruit extract. PMID:24117072

Lee, Hyo-Jin; Jeong, Yun-Jeong; Lee, Tae-Sung; Park, Yoon-Yub; Chae, Whi-Gun; Chung, Il-Kyung; Chang, Hyeun-Wook; Kim, Cheorl-Ho; Choi, Yung-Hyun; Kim, Wun-Jae; Moon, Sung-Kwon; Chang, Young-Chae

2013-01-01

53

Human anti-microbial cathelicidin peptide LL-37 suppresses the LPS-induced apoptosis of endothelial cells.  

PubMed

Sepsis is a systemic disease resulting from harmful host response to bacterial infections. During the exacerbation of severe sepsis or septic shock, apoptosis of endothelial cells is induced in susceptible organs such as the lung and liver and triggers microcirculatory disorder and organ dysfunction. LPS, an outer membrane component of Gram-negative bacteria, is one of the major virulence factors for the pathogenesis. We previously reported that LL-37, a human anti-microbial cathelicidin peptide, potently neutralizes the biological activity of LPS and protects mice from lethal endotoxin shock. However, the effect of LL-37 on the LPS-induced endothelial cell apoptosis remains to be clarified. In this study, to further elucidate the action of LL-37 on severe sepsis/endotoxin shock, we investigated the effects of LL-37 on the LPS-induced endothelial cell apoptosis in vitro and in vivo using lung-derived normal human microvascular blood vessel endothelial cells (HMVEC-LBls) and D-galactosamine hydrochloride (D-GalN)-sensitized murine endotoxin shock model. LL-37 suppressed the LPS-induced apoptosis of HMVEC-LBls. In addition, LL-37 inhibited the binding of LPS possibly to the LPS receptors (CD14 and toll-like receptor 4) expressed on the cells. Thus, LL-37 can suppress the LPS-induced apoptosis of HMVEC-LBls via the inhibition of LPS binding to the cells. Furthermore, LL-37 drastically suppressed the apoptosis of hepatic endothelial cells as well as hepatocytes in the liver of murine endotoxin shock model. Together, these observations suggest that LL-37 could suppress the LPS-induced apoptosis of endothelial cells, thereby attenuating lethal sepsis/endotoxin shock. PMID:21393634

Suzuki, Kaori; Murakami, Taisuke; Kuwahara-Arai, Kyoko; Tamura, Hiroshi; Hiramatsu, Keiichi; Nagaoka, Isao

2011-03-01

54

In vivo morphine treatment synergistically increases LPS-induced caspase activity in immune organs  

PubMed Central

Apoptosis is an important mechanism for the elimination of infected cells, which would normally serve as hosts for further pathogen replication. Apoptosis is initiated through complex pathways involving a family of cysteine proteases known as caspases. The detection of apoptosis is essential for understanding the long-term health effects inflicted by the therapeutic use of opiate drugs such as morphine for pain treatment following major trauma or disease and abusive use of such drugs in addiction. Common practices of apoptosis detection involve the removal of tissues, which subsequently induce spontaneous apoptosis unrelated to the actual effects of the opioid drug exposure. The objective of this study was to develop an in vivo detection method for assessing morphine’s ability to directly induce apoptosis, and in the combination of morphine following an inflammatory response induced by lipopolysaccharide (LPS). Mice were administered saline, morphine, LPS, or a combination of morphine and LPS. Prior to sacrifice, mice were injected with a poly-caspase-specific apoptosis detection probe, to detect internal caspase activity in vivo. Administration of morphine alone did not directly induce apoptosis. However, morphine significantly enhanced the LPS induced apoptosis in splenocyte and bone marrow cells as well as in spleen, liver, and thymus tissues. The use of a poly-caspase detection probe methodology, to label apoptotic cells in vivo, provides a powerful quantitative tool for the in vivo analysis of caspase activity.

Olin, Michael; Lee, Brian; Roy, Sabita; Molitor, Thomas

2013-01-01

55

Mycobacterium tuberculosis lipoarabinomannan enhances LPS-induced TNF-? production and inhibits NO secretion by engaging scavenger receptors.  

PubMed

Lipoarabinomannan capped with terminal oligomannosides (ManLAM) is a component of mycobacteria cell wall enabling Mycobacterium tuberculosis to infect macrophages. We found that short treatment (3.5h) of macrophage-like J774 cells and thioglycollate-elicited peritoneal murine macrophages with ManLAM and its deacylated form enhanced LPS-stimulated release of tumor necrosis factor-? (TNF-?). In contrast, prolong incubation of J774 cells with ManLAM (16h) led to inhibition of LPS-stimulated TNF-? production. LPS-triggered secretion of nitric oxide (NO) was suppressed by ManLAM and its deacylated form. Effects of ManLAM and its deacylated derivative were mimicked by dextran sulfate, a general ligand of scavenger receptors. The enhancement of LPS-induced TNF-? production by dextran sulfate was partially reversed by an antibody neutralizing scavenger receptor SR-PSOX/CXCL16 while the stimulatory activity of deacylated ManLAM was reversed by an antibody neutralizing class B scavenger receptor CD36. Our data suggest that CD36 mediates the activity of ManLAM and its deacylated form leading to TNF-? release in LPS-stimulated J774 cells and peritoneal murine macrophages, while NO production is modulated by unknown scavenger receptors. PMID:21419839

Józefowski, Szczepan; Sobota, Andrzej; Paw?owski, Andrzej; Kwiatkowska, Katarzyna

2011-03-23

56

Anti-inflammatory activity of diterpenes from Croton stellatopilosus on LPS-induced RAW264.7 cells.  

PubMed

An acyclic diterpene (plaunotol; 1) and two furanoditerpenes (plaunolide, 2 and plaunol E, 3), were isolated from Croton stellatopilosus leaves, and assessed for their inhibitory activity on nitric oxide (NO) production by lipopolysaccharide (LPS)-induced RAW264.7 cells. Plaunotol, plaunolide and plaunol E exhibited inhibitory activity with IC(50) values of 3.41, 17.09 and 2.79 ?M, respectively. Cytotoxic effects were observed at concentrations of ?100 ?M for plaunotol and ?10 ?M for plaunol E. In order to understand the mechanism of this anti-inflammatory activity, transcription profiles of the COX-1, COX-2 and iNOS genes were measured using a quantitative RT-PCR technique. The level of gene expression was expressed as a relative quantitation according to the comparative C (T) method. The results indicated that plaunotol stimulated the COX-1 and COX-2 genes, and suppressed expression of the iNOS gene. Treatment of cells with plaunolide caused a downregulation of the expressions of the COX-1, COX-2 and iNOS genes. In contrast, plaunol E inhibited the expression of the COX-2, stimulated COX-1 and iNOS expressions. In summary, the present study shows that different diterpenes from C. stellatopilosus leaves exhibit anti-inflammatory activity towards LPS-activated RAW264.7 cells by different mechanisms. Our results provide data to support further investigations into the possibility that these diterpenes could be alternatives to act as anti-inflammatory agents. PMID:22529050

Premprasert, Charoenwong; Tewtrakul, Supinya; Plubrukarn, Anuchit; Wungsintaweekul, Juraithip

2012-04-12

57

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.

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

2009-01-01

58

Mechanical Ventilation Enhances HMGB1 Expression in an LPS-Induced Lung Injury Model  

PubMed Central

Background Mechanical ventilation (MV) can augment inflammatory response in lipopolysaccharide (LPS) challenged lungs. High mobility group box 1 protein (HMGB1) is a pro-inflammatory mediator in ventilator-induced lung injury, but its mechanisms are not well defined. This study investigated the role of HMGB1 in lung inflammation in response to the combination of MV and LPS treatment. Methods Forty-eight male Sprague-Dawley rats were randomized to one of four groups: sham control; LPS treatment; mechanical ventilation; mechanical ventilation with LPS treatment. Mechanically ventilated animals received 10 ml/kg tidal volumes at a rate of 40 breaths/min for 4 h. In the HMGB1-blockade study, sixteen rats were randomly assigned to HMGB1 antibody group or control antibody group and animals were subjected to MV+LPS as described above. A549 cells were pre-incubated with different signal inhibitors before subjected to 4 h of cyclic stretch. Lung wet/dry weight (W/D) ratio, total protein and IgG concentration, number of neutrophils in bronchoalveolar lavage fluid (BALF), and lung histological changes were examined. The levels of interleukin-1? (IL-1?), IL-6, tumor necrosis factor-? (TNF-?), macrophage inflammatory protein-2 (MIP-2) and HMGB1 in BALF were measured using ELISA. Real-time quantitative PCR and Western blot were used to analyze mRNA and protein expression of HMGB1. Western blot were employed to analyze the activation of I?B-?, NF-?B, JNK, ERK, and p38. Results MV significantly augmented LPS-induced lung injury and HMGB1 expression, which was correlated with the increase in IL-1?, IL-6 and MIP-2 levels in BALF. In vivo, intratracheally administration of HMGB1 antibody significantly attenuated pulmonary inflammatory injury. In vitro experiments showed cyclic stretch induced HMGB1 expression through signaling pathways including p38 and NF-?B. Conclusions The findings indicated that moderate tidal volume MV augmented LPS induced lung injury by up-regulating HMGB1. The mechanism of HMGB1-mediated lung injury is likely to be signaling through p38 and NF-?B pathways.

Ding, Ning; Wang, Fang; Xiao, Hui; Xu, Lixin; She, Shouzhang

2013-01-01

59

MAPK signaling is required for LPS-induced VEGF in pulp stem cells.  

PubMed

Caries-induced pulpitis is typically accompanied by an increase in dental pulp microvascular density. However, the mechanisms by which dental pulp cells recognize lipopolysaccharides (LPSs) remain unclear. We hypothesized that Porphyromonas endodontalis and Escherichia coli LPSs induce vascular endothelial growth factor (VEGF) expression in dental pulp stem cells (DPSC) and human dental pulp fibroblasts (HDPF) through mitogen-activated protein kinase (MAPK) signaling. ELISA, semi-quantitative RT-PCR, immunofluorescence, and Western blots were used. Here, we observed that LPSs induced VEGF expression in DPSC and HDPF cells, and both cell types express Toll-like receptor 4 (TLR- 4). Notably, LPS-induced VEGF is associated with phosphorylation of protein kinase C (PKC zeta) and extracellular signal-regulator kinase (ERK1/2) and is dependent upon MAPK activation. Analysis of these data, collectively, unveils a signaling pathway responsible for synthesis of VEGF by pulp cells and suggests a novel therapeutic target for the management of vascular responses in teeth with pulpitis. PMID:20110511

Botero, T M; Son, J S; Vodopyanov, D; Hasegawa, M; Shelburne, C E; Nör, J E

2010-01-28

60

Transactivation of EGFR by LPS Induces COX-2 Expression in Enterocytes  

PubMed Central

Necrotizing enterocolitis (NEC) is the leading cause of gastrointestinal morbidity and mortality in preterm infants. NEC is characterized by an exaggerated inflammatory response to bacterial flora leading to bowel necrosis. Bacterial lipopolysaccharide (LPS) mediates inflammation through TLR4 activation and is a key molecule in the pathogenesis of NEC. However, LPS also induces cyclooxygenase-2 (COX-2), which promotes intestinal barrier restitution through stimulation of intestinal cell survival, proliferation, and migration. Epidermal growth factor receptor (EGFR) activation prevents experimental NEC and may play a critical role in LPS-stimulated COX-2 production. We hypothesized that EGFR is required for LPS induction of COX-2 expression. Our data show that inhibiting EGFR kinase activity blocks LPS-induced COX-2 expression in small intestinal epithelial cells. LPS induction of COX-2 requires Src-family kinase signaling while LPS transactivation of EGFR requires matrix metalloprotease (MMP) activity. EGFR tyrosine kinase inhibitors block LPS stimulation of mitogen-activated protein kinase ERK, suggesting an important role of the MAPK/ERK pathway in EGFR-mediated COX-2 expression. LPS stimulates proliferation of IEC-6 cells, but this stimulation is inhibited with either the EGFR kinase inhibitor AG1478, or the selective COX-2 inhibitor Celecoxib. Taken together, these data show that EGFR plays an important role in LPS-induction of COX-2 expression in enterocytes, which may be one mechanism for EGF in inhibition of NEC.

McElroy, Steven J.; Hobbs, Stuart; Kallen, Michael; Tejera, Noemi; Rosen, Michael J.; Grishin, Anatoly; Matta, Poojitha; Schneider, Claus; Upperman, Jeffrey; Ford, Henri; Polk, D. Brent; Weitkamp, Jorn-Hendrik

2012-01-01

61

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

PubMed Central

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.

Gonzalez-Teran, Barbara; Cortes, Jose R.; Manieri, Elisa; Matesanz, Nuria; Verdugo, ?ngeles; Rodriguez, Maria E.; Gonzalez-Rodriguez, ?gueda; Valverde, ?ngela; Martin, Pilar; Davis, Roger J.; Sabio, Guadalupe

2012-01-01

62

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

63

Progesterone is essential for protecting against LPS-induced pregnancy loss. LIF as a potential mediator of the anti-inflammatory effect of progesterone.  

PubMed

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, María V; Billi, Silvia C; Wolfson, Manuel L; Franchi, Ana M

2013-02-07

64

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.

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

2013-01-01

65

Aspirin-triggered lipoxin A4 attenuates LPS-induced pro-inflammatory responses by inhibiting activation of NF-?B and MAPKs in BV-2 microglial cells  

PubMed Central

Background Microglial activation plays an important role in neurodegenerative diseases through production of nitric oxide (NO) and several pro-inflammatory cytokines. Lipoxins (LXs) and aspirin-triggered LXs (ATLs) are considered to act as 'braking signals' in inflammation. In the present study, we investigated the effect of aspirin-triggered LXA4 (ATL) on infiammatory responses induced by lipopolysaccharide (LPS) in murine microglial BV-2 cells. Methods BV-2 cells were treated with ATL prior to LPS exposure, and the effects of such treatment production of nitric oxide (NO), inducible nitric oxide synthase (iNOS), interleukin-1? (IL-1?) and tumour necrosis factor-? (TNF-?) were analysed by Griess reaction, ELISA, western blotting and quantitative RT-PCR. Moreover, we investigated the effects of ATL on LPS-induced nuclear factor-?B (NF-?B) activation, phosphorylation of mitogen-activated protein kinases (MAPKs) and activator protein-1 (AP-1) activation. Results ATL inhibited LPS-induced production of NO, IL-1? and TNF-? in a concentration-dependent manner. mRNA expressions for iNOS, IL-1? and TNF-? in response to LPS were also decreased by ATL. These effects were inhibited by Boc-2 (a LXA4 receptor antagonist). ATL significantly reduced nuclear translocation of NF-?B p65, degradation of the inhibitor I?B-?, and phosphorylation of extracellular signal-regulated kinase (ERK) and p38 MAPK in BV-2 cells activated with LPS. Furthermore, the DNA binding activity of NF-?B and AP-1 was blocked by ATL. Conclusions This study indicates that ATL inhibits NO and pro-inflammatory cytokine production at least in part via NF-?B, ERK, p38 MAPK and AP-1 signaling pathways in LPS-activated microglia. Therefore, ATL may have therapeutic potential for various neurodegenerative diseases.

2011-01-01

66

LPS- induced inflammation exacerbates phospho-tau pathology in rTg4510 mice  

PubMed Central

Inflammation and microglial activation are associated with Alzheimer's disease (AD) pathology. Somewhat surprisingly, injection of a prototypical inflammatory agent, lipopolysaccharide (LPS) into brains of amyloid precursor protein (APP) transgenic mice clears some of the pre-existing amyloid deposits. It is less well understood how brain inflammation modulates tau pathology in the absence of A?. These studies examined the role of LPS-induced inflammation on tau pathology. We used transgenic rTg4510 mice, which express the P301L mutation (4R0N TauP301L) and initiate tau pathology between 3-5 months of age. First, we found an age-dependent increase in several markers of microglial activation as these rTg4510 mice aged and tau tangles accumulated. LPS injections into the frontal cortex and hippocampus induced significant activation of CD45 and arginase 1 in rTg4510 and non-transgenic mice. In addition, activation of YM1 by LPS was exaggerated in transgenic mice relative to non-transgenic animals. Expression of Ser199/202 and phospho-tau Ser396 was increased in rTg4510 mice that received LPS compared to vehicle injections. However, the numbers of silver-positive neurons, implying presence of more pre- and mature tangles, was not significantly affected by LPS administration. These data suggest that inflammatory stimuli can facilitate tau phosphorylation. Coupled with prior results demonstrating clearance of A? by similar LPS injections, these results suggest that brain inflammation may have opposing effects on amyloid and tau pathology, possibly explaining the failures (to date) of anti-inflammatory therapies in AD patients.

2010-01-01

67

Lactoferrin down-regulates the LPS-induced cytokine production in monocytic cells via NF-?B  

Microsoft Academic Search

Lactoferrin, a glycoprotein present in milk, mucosal secretions and neutrophils contributes to host defense. We have previously shown that orally given milk lactoferrin (LF) mediates anti-infectious and anti-inflammatory activities in vivo. Moreover, we have shown that LF could inhibit the LPS-induced IL-6 secretion in a human monocytic cell line, THP-1. This observation was expanded in the present study investigating the

Liliana Hĺversen; Bertil G Ohlsson; Mirjana Hahn-Zoric; Lars Ĺ Hanson; Inger Mattsby-Baltzer

2002-01-01

68

Adenosine receptor A2b on hematopoietic cells mediates LPS-induced migration of PMNs into the lung interstitium.  

PubMed

Uncontrolled transmigration of polymorphonuclear leukocytes (PMNs) into the different compartments of the lungs (intravascular, interstitial, alveolar) is a critical event in the early stage of acute lung injury and acute respiratory distress syndrome. Adenosine receptor A(2b) is highly expressed in the inflamed lungs and has been suggested to mediate cell trafficking. In a murine model of LPS-induced lung inflammation, we investigated the role of A(2b) on migration of PMNs into the different compartments of the lung. In A(2b)(-/-) mice, LPS-induced accumulation of PMNs was significantly higher in the interstitium, but not in the alveolar space. In addition, pulmonary clearance of PMNs was delayed in A(2b)(-/-) mice. Using chimeric mice, we identified A(2b) on hematopoietic cells as crucial for PMN migration. A(2b) did not affect the release of relevant chemokines into the alveolar space. LPS-induced microvascular permeability was under the control of A(2b) on both hematopoietic and nonhematopoietic cells. Activation of A(2b) on endothelial cells also reduced formation of LPS-induced stress fibers, highlighting its role for endothelial integrity. A specific A(2b) agonist (BAY 60-6583) was effective in decreasing PMN migration into the lung interstitium and microvascular permeability. In addition, in vitro transmigration of human PMNs through a layer of human endothelial or epithelial cells was A(2b) dependent. Activation of A(2b) on human PMNs reduced oxidative burst activity. Together, our results demonstrate anti-inflammatory effects of A(2b) on two major characteristics of acute lung injury, with a distinct role of hematopoietic A(2b) for cell trafficking and endothelial A(2b) for microvascular permeability. PMID:22707616

Konrad, Franziska M; Witte, Esther; Vollmer, Irene; Stark, Stefanie; Reutershan, Jörg

2012-06-15

69

Resolvin D1 reduces deterioration of tight junction proteins by upregulating HO-1 in LPS-induced mice.  

PubMed

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) is characterized by increased pulmonary permeability with high mortality. Resolvin D1 (RvD1), which has potent anti-inflammatory and pro-resolving activity, can attenuate pulmonary edema in the animal model of ALI. However, the mechanism underlying the protection of RvD1 on pulmonary edema is still unknown. Here we explore the effects and mechanism of RvD1 on the disruption of tight junction protein that results in the permeability edema in a model of lipopolysaccharide (LPS)-induced ALI. The severity of pulmonary edema was assessed by wet-to-dry rate and Evans blue infiltration; expressions of tight junction (TJ) proteins occludin and zona occludin-1 (ZO-1) were examined by immunofluorescence staining and western blot; mRNA in lung tissue was studied by real time-PCR; the TUNEL kit was performed for the detection of apoptosis of pulmonary barrier. Twenty-four hours after LPS inhalation by mice, wet-to-dry rate and Evans blue infiltration indicated that pretreatment with RvD1 relieved the pulmonary edema and pulmonary capillary permeability. Moreover, RvD1 attenuated the LPS-induced deterioration of TJ protein ZO-1 and occludin significantly. And we found that RvD1 increased heme oxygenase-1 (HO-1) expression contributed to the protection on the deterioration of TJs. In addition, we found that RvD1 could reduce pulmonary cellular apoptosis in LPS-induced mice. In conclusion, RvD1 possesses the ability that relieves the pulmonary edema and restores pulmonary capillary permeability and reduces disruption of TJs in LPS-induced ALI of mice, at least in part, by upregulating HO-1 expression. PMID:23857007

Xie, Wanli; Wang, Huiqing; Wang, Lei; Yao, Chengye; Yuan, Ruixia; Wu, Qingping

2013-07-15

70

EPA and DHA reduce LPS-induced inflammation responses in HK-2 cells: Evidence for a PPAR-?–dependent mechanism  

Microsoft Academic Search

EPA and DHA reduce LPS-induced inflammation responses in HK-2 cells: Evidence for a PPAR-?–dependent mechanism.BackgroundRecent studies have shown that fish oil, containing ?-3 polyunsaturated fatty acids (?-3 PUFAs) eicosapentaenoic acid (EPA) (C20:5 ? 3), and docosahexaenoic acid (DHA) (C22:6 ? 3) retard the progression of renal disease, especially in IgA nephropathy (IgAN). Despite increasing knowledge of the beneficial effects of

HANG LI; Xiong Z. Ruan; Stephen H. Powis; RAY FERNANDO; Wint Y. Mon; David C. Wheeler; John F. Moorhead; ZAC VARGHESE

2005-01-01

71

Disparate roles of marrow- and parenchymal cell-derived TLR4 signaling in murine LPS-induced systemic inflammation  

PubMed Central

Systemic inflammatory response syndrome (SIRS) occurs in a range of infectious and non-infectious disease processes. Toll-like receptors (TLRs) initiate such responses. We have shown that parenchymal cell TLR4 activation drives LPS-induced systemic inflammation; SIRS does not develop in mice lacking TLR4 expression on parenchymal cells. The parenchymal cell types whose TLR4 activation directs this process have not been identified. Employing a bone marrow transplant model to compartmentalize TLR4 signaling, we characterized blood neutrophil and cytokine responses, NF-?B1 activation, and Tnf-?, Il6, and Ccl2 induction in several organs (spleen, aorta, liver, lung) near the time of LPS-induced symptom onset. Aorta, liver, and lung gene responses corresponded with both LPS-induced symptom onset patterns and plasma cytokine/chemokine levels. Parenchymal cells in aorta, liver, and lung bearing TLR4 responded to LPS with chemokine generation and were associated with increased plasma chemokine levels. We propose that parenchymal cells direct SIRS in response to LPS.

Juskewitch, Justin E.; Platt, Jeffrey L.; Knudsen, Bruce E.; Knutson, Keith L.; Brunn, Gregory J.; Grande, Joseph P.

2012-01-01

72

PDTC attenuate LPS-induced kidney injury in systemic lupus erythematosus-prone MRL/lpr mice.  

PubMed

Lipopolysaccharide (LPS) from bacteria can accelerate and exacerbate lupus nephritis (LN) and induce infiltrating inflammatory cells in kidney in animal models. Pyrrolidine dithiocarbamate (PDTC) is known to exert anti-inflammatory effects. Monocyte chemoattractant protein-1(MCP-1) is upregulated by various stimuli, including LPS, high glucose, and hyperosmolality. However, the molecular mechanisms of transcriptional regulation of the MCP-1 protein expression with LPS are poorly understood. Expression of MCP-1 was examined by western blot and enzyme-linked immunosorbent assay, respectively. The activity of nuclear factor (NF)-kappaB was measured by western blot. These mice have uncontrolled proliferation of T cells, an impaired response to T cell mitogen and produce autoantibodies against nuclear antigens, including DNA. We found that after LPS treatment for 14 weeks, LPS increased MCP-1 protein expression in kidney, which was significantly suppressed by antioxidant PDTC. The expression of NF-?B, pERK, pJNK and MCP-1 were increased, pp38 expression was decreased significantly, concomitantly with sera anti-dsDNA, MCP-1 and the acceleration of severity of autoimmune kidney injury. LPS induce markedly neutrophil infiltration in the glomerulus, especially around the mesangial region. PDTC reduced the number of infiltrating inflammatory cells and severity of kidney injury via inhibiting NF-?B and p38 MAPK activity. They also markedly prevented LPS-induced pJNK and MCP-1. Therefore, MCP-1 may be responsible for the recruitment and activation of leukocytes in diseased kidneys in female MRL/lpr mice. In this study, the long-term administration of PDTC had impacts on the prevention of end-stage organ damage induced by LPS treated. We demonstrated that PDTC inhibited LPS-induced monocyte migration and attenuated LPS-induced p38 MAPK activation. Based on these data we infer that PDTC inhibits LPS-induced MCP-1 expression, secretion and function through inhibition of NF-?B and p38 MAPK activity. Our study suggests that MAPK is an important therapeutic target of monocyte recruitment and accumulation within the glomerulus in inflammatory renal disease. These results suggest that PDTC protects against kidney inflammation of SLE at least in part via NF-?B and MAPK signaling pathways induction, and that inhibitory action on anti-dsDNA may be associated with the protective mechanism of PDTC. In summary, PDTC pretreatment attenuates LPS-induced kidney injury in female MRL/lpr mice through regulating NF-?B and MAPK signaling pathways. Our results indicate that LPS induces MCP-1 mainly through activating NF-?B and its downstream MAPK, and that such effect was inhibited by PDTC, suggesting the efficacy of PDTC in preventing kidney fibrosis in lupus-prone mice. Therefore, appropriate inhibition of NF-?B activation may attenuate the kidney injury in lupus-prone mice. PMID:22318546

Zhai, Jin-Xia; Zhang, Zhao-Xiang; Feng, Ya-Juan; Ding, Shu-Shu; Wang, Xing-Hua; Zou, Li-Wei; Ye, Dong-Qing

2012-02-09

73

Assessment of weight bearing changes and pharmacological antinociception in mice with LPS-induced monoarthritis using the Catwalk gait analysis system  

Microsoft Academic Search

AimsWe evaluated the possibility of using the video-based Catwalk gait analysis method to measure weight bearing changes and for testing pharmacological antinociception in freely moving mice with lipopolysaccharide (LPS)-induced monoarthritis.

Willias Masocha; Subramanian S. Pavarthy

2009-01-01

74

Ghrelin inhibits LPS-induced release of IL-6 from mouse dopaminergic neurones  

PubMed Central

Background Ghrelin is an orexigenic stomach hormone that acts centrally to increase mid-brain dopamine neurone activity, amplify dopamine signaling and protect against neurotoxin-induced dopamine cell death in the mouse substantia nigra pars compacta (SNpc). In addition, ghrelin inhibits the lipopolysaccharide (LPS)-induced release of pro-inflammatory cytokines from peripheral macrophages, T-cells and from LPS stimulated microglia. Here we sought to determine whether ghrelin attenuates pro-inflammatory cytokine release from dopaminergic neurones. Findings The dopaminergic SN4741 cell-line, which derives from the mouse substantia nigra (SN) and expresses the ghrelin-receptor (growth hormone secretagogue receptor (GHS-R)) and the ghrelin-O-acyl transferase (GOAT) enzyme, was used to determine the neuro-immunomodulatory action of ghrelin. We induced innate immune activation via LPS challenge (1 ?g/ml) of SN4741 neurones that had been pre-cultured in the presence or absence of ghrelin (1, 10, 100 nM) for 4 h. After 24 h supernatants were collected for detection of IL-1 beta (IL-1? ), TNF alpha (TNF-?) and IL-6 cytokines via enzyme linked immunosorbent assay (ELISA) analysis. Nuclear translocation of the transcription factor nuclear factor kappa B (NF-?B) was analyzed by Western blotting, and to determine viability of treatments a cell viability assay and caspase-3 immunohistochemistry were performed. We provide evidence that while IL-1? and TNF-? were not detectable under any conditions, SN4741 neurones constitutively released IL-6 under basal conditions and treatment with LPS significantly increased IL-6 secretion. Pre-treatment of neurones with ghrelin attenuated LPS-mediated IL-6 release at 24 h, an affect that was inhibited by the GHS-R antagonist [D-Lys3]-GHRP-6. However, while ghrelin pre-treatment attenuated the LPS-mediated increase in NF-?B, there was no alteration in its nuclear translocation. Cell viability assay and caspase-3 immunocytochemistry demonstrated that the results were independent from activation of cytotoxic and/or apoptotic mechanisms in the neuronal population, respectively. Conclusion Our results provide evidence that the gut-hormone, ghrelin, attenuates IL-6 secretion to LPS challenge in mid-brain dopaminergic neurones. These data suggest that ghrelin may protect against dopaminergic SN nerve cell damage or death via modulation of the innate immune response.

2013-01-01

75

The P2 receptor antagonist PPADS abrogates LPS-induced neutrophil migration in the murine air pouch via inhibition of MIP2 and KC production  

Microsoft Academic Search

In this work, we show that P2 nucleotide receptors control lipopolysaccharide (LPS)-induced neutrophil migration in the mouse air pouch model. Neutrophil infiltration in LPS-treated air pouches was reduced by the intravenous (iv) administration of the non-selective P2 receptor antagonist PPADS but not by suramin and RB-2. In addition, the iv administration of a P2 receptor ligand, UTP, enhanced LPS-induced neutrophil

Filip Kukulski; Fethia Ben Yebdri; Fariborz Bahrami; Sébastien A. Lévesque; Mireia Martín-Satué; Jean Sévigny

2010-01-01

76

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

PubMed

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 264.7 macrophages and for its cytotoxicity against four human cancer cell lines. A. wiedemanniana oil, rich of oxygenated monoterpenes (25.4%), showed a good antibacterial activity against Gram-positive bacteria and a good activity against the two Gram-negative bacteria, Escherichia coli and Proteus vulgaris. Besides that, it exhibited a high inhibitory effect on the LPS-induced nitrite production and a strong cytotoxic activity, especially against amelanotic melanoma (C32) and large lung cell carcinoma (COR-L23) cell lines. PMID:22124231

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

2011-11-29

77

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.

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

78

Cobalt protoporphyrin accelerates TFEB activation and lysosome reformation during LPS-induced septic insults in the rat heart.  

PubMed

Lipopolysaccharide (LPS)-induced myocardial dysfunction is caused, at least in part, by mitochondrial dysfunction. Mitochondrial dysfunction and the oxidative damage associated with it are scavenged through various cellular defense systems such as autophagy to prevent harmful effects. Our recent study has demonstrated that cobalt protoporphyrin IX (CoPPIX), a potent inducer of heme oxygenase-1 (HO-1), ameliorates septic liver injuries by enhancing mitochondrial autophagy in rats. In our current study, we show that CoPPIX (5 mg/kg s.c.) not only accelerates the autophagic response but also promotes lysosome reformation in the rat heart treated with LPS (15 mg/kg i.p.). Lysosomal membrane-associated protein-2 (LAMP2), which is essential to the maintenance of lysosomal functions in the heart, is depleted transiently but restored rapidly during LPS administration in the rat. Activation of transcription factor EB (TFEB), a master regulator of lysosomal biogenesis and autophagy, was also observed, indicating a hyper consumption and subsequent reformation of the lysosome to meet the increased demand for autophagosome cleaning. CoPPIX was found to promote these processes and tended to restore the LPS-induced suppression of cardiac performances whilst chloroquine (CQ; 20 mg/kg i.p.), an inhibitor of lysosomes and autophagic protein degradation, abrogates these beneficial effects. The cardioprotective effect of CoPPIX against LPS toxicity was also observed via decreased levels of cardiac releasing enzymes in the plasma. Taken together, our current data indicate that lysosome reformation mediated by TFEB may be involved in cardioprotection against LPS-induced septic insults, and serve as a novel mechanism by which CoPPIX protects the heart against oxidative stress. PMID:23457579

Unuma, Kana; Aki, Toshihiko; Funakoshi, Takeshi; Yoshida, Ken-ichi; Uemura, Koichi

2013-02-15

79

Cobalt Protoporphyrin Accelerates TFEB Activation and Lysosome Reformation during LPS-Induced Septic Insults in the Rat Heart  

PubMed Central

Lipopolysaccharide (LPS)-induced myocardial dysfunction is caused, at least in part, by mitochondrial dysfunction. Mitochondrial dysfunction and the oxidative damage associated with it are scavenged through various cellular defense systems such as autophagy to prevent harmful effects. Our recent study has demonstrated that cobalt protoporphyrin IX (CoPPIX), a potent inducer of heme oxygenase-1 (HO-1), ameliorates septic liver injuries by enhancing mitochondrial autophagy in rats. In our current study, we show that CoPPIX (5 mg/kg s.c.) not only accelerates the autophagic response but also promotes lysosome reformation in the rat heart treated with LPS (15 mg/kg i.p.). Lysosomal membrane-associated protein-2 (LAMP2), which is essential to the maintenance of lysosomal functions in the heart, is depleted transiently but restored rapidly during LPS administration in the rat. Activation of transcription factor EB (TFEB), a master regulator of lysosomal biogenesis and autophagy, was also observed, indicating a hyper consumption and subsequent reformation of the lysosome to meet the increased demand for autophagosome cleaning. CoPPIX was found to promote these processes and tended to restore the LPS-induced suppression of cardiac performances whilst chloroquine (CQ; 20 mg/kg i.p.), an inhibitor of lysosomes and autophagic protein degradation, abrogates these beneficial effects. The cardioprotective effect of CoPPIX against LPS toxicity was also observed via decreased levels of cardiac releasing enzymes in the plasma. Taken together, our current data indicate that lysosome reformation mediated by TFEB may be involved in cardioprotection against LPS-induced septic insults, and serve as a novel mechanism by which CoPPIX protects the heart against oxidative stress.

Unuma, Kana; Aki, Toshihiko; Funakoshi, Takeshi; Yoshida, Ken-ichi; Uemura, Koichi

2013-01-01

80

Anti-inflammatory activity of cinnamon water extract in vivo and in vitro LPS-induced models  

PubMed Central

Background Cinnamon bark is one of the most popular herbal ingredients in traditional oriental medicine and possesses diverse pharmacological activities including anti-bacterial, anti-viral, and anti-cancer properties. The goal of this study is to investigate the in vivo and in vitro inhibitory effect of cinnamon water extract (CWE) on lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF)-? and its underlying intracellular mechanisms. Methods CWE was orally administrated to mice for 6 days prior to intraperitoneal injection of LPS. Serum levels of TNF-? and interleukin (IL)-6 were determined 1 hour after LPS stimulation. Peritoneal macrophages from thioglycollate-injected mice were isolated and assayed for viability, cytokine expression and signaling molecules upon LPS stimulation. CWE was further fractioned according to molecular size, and the levels of total polyphenols and biological activities of each fraction were measured. Results The oral administration of CWE to mice significantly decreased the serum levels of TNF-? and IL-6. CWE treatment in vitro decreased the mRNA expression of TNF-?. CWE blocked the LPS-induced degradation of I?B? as well as the activation of JNK, p38 and ERK1/2. Furthermore, size-based fractionation of CWE showed that the observed inhibitory effect of CWE in vitro occurred in the fraction containing the highest level of total polyphenols. Conclusions Treatment with CWE decreased LPS-induced TNF-? in serum. In vitro inhibition of TNF-? gene by CWE may occur via the modulation of I?B? degradation and JNK, p38, and ERK1/2 activation. Our results also indicate that the observed anti-inflammatory action of CWE may originate from the presence of polyphenols.

2012-01-01

81

neo-Clerodane diterpenes from Ajuga decumbens and their inhibitory activities on LPS-induced NO production.  

PubMed

A phytochemical investigation of the whole plants of Ajuga decumbens led to the isolation of three new (1, 2a, and 2b) and three known (3a-3c) neo-clerodane diterpenes. Their structures were elucidated by spectroscopic data analysis (IR, ESIMS, HR-ESIMS, 1D and 2D NMR), and the structure of 1 was confirmed by X-ray crystallography. The inhibitory activities on LPS-induced NO production of the six diterpenes were evaluated and compounds 2a, 2b, and 3a showed inhibitory effects. PMID:22917649

Sun, Zhanping; Li, Yushan; Jin, Da-qing; Guo, Ping; Song, Haibin; Xu, Jing; Guo, Yuanqiang; Zhang, Lei

2012-08-21

82

Baicalein inhibits nuclear factor-?B and apoptosis via c-FLIP and MAPK in D-GalN/LPS induced acute liver failure in murine models.  

PubMed

The hepatoprotective effects and molecular mechanisms of baicalein on acute liver failure induced by d-galactosamine (d-GalN)/lipopolysaccharides (LPS) were investigated in vivo. Mice were administered with different doses of baicalein (50, 100 or 150mg/kg, p.o.) 1h before injection of d-GalN (700mg/kg)/LPS (10?g/kg) and then sacrificed 6h after treatment with d-GalN/LPS. Pretreatment with baicalein prevented d-GalN/LPS-induced liver damage by preventing associated increases of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) and by reducing serum tumor necrosis factor ? (TNF-?), nitric oxide (NO) or inducible nitric oxide synthase (iNOS) expressions. The molecular mechanisms involved in baicalein-induced inhibition of d-GalN/LPS-caused apoptosis were associated with the protection of mitochondria, increasing the Bcl-2/Bax ratio, blocking the release of cytochrome c, and suppressing the phosphorylation of I?B?, ERK and JNK. Moreover, baicalein activated c-FLIP(L), XIAP and cIAP2 proteins, potentially blocking the recruitment of NF-?B signaling molecules. The results support the investigation of baicalein as a therapeutic candidate for acute liver apoptosis or injury and indicate that baicalein might inhibit liver apoptosis by mediating one or more of these pathways. PMID:20850421

Wu, Yan-Ling; Lian, Li-Hua; Wan, Ying; Nan, Ji-Xing

2010-09-17

83

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

84

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.

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

2013-01-01

85

Aryl hydrocarbon receptor negatively regulates LPS-induced IL-6 production through suppression of histamine production in macrophages.  

PubMed

Macrophages play a pivotal role in innate immune responses to pathogens via toll-like receptors. We previously demonstrated that aryl hydrocarbon receptor (Ahr) in combination with signal transducer and activator of transcription 1 (Stat1) negatively regulates pro-inflammatory cytokine production by inhibiting nuclear factor-?B activation in macrophages after LPS stimulation. Here, we show that Ahr also negatively regulates production of the pro-inflammatory cytokine IL-6 by suppressing histamine production in macrophages stimulated by LPS. We found that Ahr-Sp1 complex, independent of Stat1, represses histidine decarboxylase expression by inhibiting LPS-induced Sp1 phosphorylation on Ser residues in macrophages; this leads to suppression of histamine production. Moreover, we found that loratadine and chlorpromazine, histamine 1 receptor (H1R) antagonists, more effectively impair the production of LPS-induced IL-6 than that of other inflammatory cytokines in Ahr(-/-) macrophages. Collectively, these results demonstrate that Ahr negatively regulates IL-6 production via H1R signaling through the suppression of histamine production in macrophages following LPS stimulation. PMID:21930594

Masuda, Kazuya; Kimura, Akihiro; Hanieh, Hamza; Nguyen, Nam Trung; Nakahama, Taisuke; Chinen, Ichino; Otoyo, Yuichi; Murotani, Tomotaka; Yamatodani, Atsushi; Kishimoto, Tadamitsu

2011-09-19

86

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.

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

2012-01-01

87

LPS induces pp60c-src-mediated tyrosine phosphorylation of Hsp90 in lung vascular endothelial cells and mouse lung.  

PubMed

Heat shock protein 90 (Hsp90) inhibitors were initially developed as anticancer agents; however, it is becoming increasing clear that they also possess potent anti-inflammatory properties. Posttranslational modifications of Hsp90 have been reported in tumors and have been hypothesized to affect client protein- and inhibitor-binding activities. In the present study we investigated the posttranslational modification of Hsp90 in inflammation. LPS, a prototypical inflammatory agent, induced concentration- and time-dependent tyrosine (Y) phosphorylation of Hsp90? and Hsp90? in bovine pulmonary arterial and human lung microvascular endothelial cells (HLMVEC). Mass spectrometry identified Y309 as a major site of Y phosphorylation on Hsp90? (Y300 of Hsp90?). LPS-induced Hsp90 phosphorylation was prevented by the Hsp90 inhibitor 17-allyl-amino-demethoxy-geldanamycin (17-AAG) in vitro as well as in lungs from LPS-treated mice, in vivo. Furthermore, 17-AAG prevented LPS-induced pp60src activation. LPS-induced Hsp90 phosphorylation was also prevented by the pp60src inhibitor PP2. Additionally, Hsp90 phosphorylation was induced by infecting cells with a constitutively active pp60src adenovirus, whereas either a dominant-negative pp60src adenovirus or reduced expression of pp60src by a specific siRNA prevented the LPS-induced Y phosphorylation of Hsp90. Transfection of HLMVEC with the nonphosphorylatable Hsp90? Y300F mutant prevented LPS-induced Hsp90? tyrosine phosphorylation but not pp60src activation. Furthermore, the Hsp90? Y300F mutant showed a reduced ability to bind the Hsp90 client proteins eNOS and pp60src and HLMVEC transfected with the mutant exhibited reduced LPS-induced barrier dysfunction. We conclude that inflammatory stimuli cause posttranslational modifications of Hsp90 that are Hsp90-inhibitor sensitive and may be important to the proinflammatory actions of Hsp90. PMID:23585225

Barabutis, Nektarios; Handa, Vaishali; Dimitropoulou, Christiana; Rafikov, Ruslan; Snead, Connie; Kumar, Sanjiv; Joshi, Atul; Thangjam, Gagan; Fulton, David; Black, Stephen M; Patel, Vijay; Catravas, John D

2013-04-12

88

Protective effects of endothelin-A receptor antagonist BQ123 against LPS-induced oxidative stress in lungs.  

PubMed

The aim of this study was to assess whether endothelin-A receptor (ET(A)-R) blocker, BQ123, influences lung edema, lipid peroxidation TBARS), hydrogen peroxide (H(2)O(2)), TNF-? concentration or the glutathione redox system in the lung homogenates obtained from LPS-induced endotoxic shock rats. The study was performed on male Wistar rats (n = 6 per group) divided into groups: (1) saline, (2) LPS (15 mg/kg)-saline, (3) BQ123 (0.5 mg/kg)-LPS, (4) BQ123 (1 mg/kg)-LPS. The ET(A)-R antagonist was injected intravenously 30 min before LPS administration. Five hours after saline or LPS administration, animals were sacrificed and lungs were isolated for indices of lung edema, oxidative stress and TNF-? concentration. Injection of LPS alone resulted in lung edema development and a marked increase in TNF-? (p < 0.02), TBARS (p < 0.02), and H(2)O(2) (p < 0.01) concentrations as well as a depletion of total glutathione (p < 0.01). Administration of BQ123 (1 mg/kg), before LPS challenge, led to a significant reduction in TNF-? and H(2)O(2) concentrations (p < 0.05) and elevation of both total glutathione and the GSH/GSSG ratio (p < 0.05). However, it did not prevent LPS-induced TBARS increase and lung edema formation. Interestingly, a lower dose of BQ123 was much more effective in decreasing H(2)O(2), TBARS, as well as TNF-? levels (p < 0.02, p < 0.05, p < 0.05, respectively). That dose was also effective in prevention of lung edema development (p < 0.01). Taken together, the obtained results indicate that BQ123 is highly effective in decreasing LPS-induced oxidative stress in lungs. Moreover, the dose of 0.5 mg/kg of the antagonist showed to be more effective in decreasing free radical generation and lung edema in endotoxemic rats. PMID:21602605

Piechota, Aleksandra; Pola?czyk, Andrzej; Goraca, Anna

2011-01-01

89

Aloe vera downregulates LPS-induced inflammatory cytokine production and expression of NLRP3 inflammasome in human macrophages.  

PubMed

Aloe vera has been used in traditional herbal medicine as an immunomodulatory agent inducing anti-inflammatory effects. However, its role on the IL-1? inflammatory cytokine production has not been studied. IL-1? production is strictly regulated both at transcriptional and posttranslational levels through the activity of Nlrp3 inflammasome. In this study we aimed to determine the effect of Aloe vera on the molecular mechanisms of Nlrp3 inflammasome-mediated IL-1? production in LPS-activated human THP-1 cells and monocyte-derived macrophages. Our results show that Aloe vera significantly reduced IL-8, TNF?, IL-6 and IL-1? cytokine production in a dose dependent manner. The inhibitory effect was substantially more pronounced in the primary cells. We found that Aloe vera inhibited the expression of pro-IL-1?, Nlrp3, caspase-1 as well as that of the P2X7 receptor in the LPS-induced primary macrophages. Furthermore, LPS-induced activation of signaling pathways like NF-?B, p38, JNK and ERK were inhibited by Aloe vera in these cells. Altogether, we show for the first time that Aloe vera-mediated strong reduction of IL-1? appears to be the consequence of the reduced expression of both pro-IL-1? as well as Nlrp3 inflammasome components via suppressing specific signal transduction pathways. Furthermore, we show that the expression of the ATP sensor P2X7 receptor is also downregulated by Aloe vera that could also contribute to the attenuated IL-1? cytokine secretion. These results may provide a new therapeutic approach to regulate inflammasome-mediated responses. PMID:23911403

Budai, Marietta M; Varga, Aliz; Milesz, Sándor; T?zsér, József; Benk?, Szilvia

2013-08-01

90

Caspase1 processes IFNgamma-inducing factor and regulates LPS-induced IFN gamma production  

Microsoft Academic Search

Interferon-gamma-inducing factor (IGIF, interleukin-18) is a recently described cytokine that shares structural features with the inter-leukin-1 (IL-1) family of proteins and functional properties with IL-121-4. Like IL-12, IGIF is a potent inducer of interferon (IFN)-gamma from T cells and natural killer cells1-3,5,6. IGIF is synthesized as a biologically inactive precursor molecule (proIGIF). The cellular production of IL-lbeta, a cytokine implicated

Tariq Ghayur; Subhashis Banerjee; Margaret Hugunin; Deborah Butler; Linda Herzog; Adam Carter; Lucia Quintal; Les Sekut; Robert Talanian; Michael Paskind; Winnie Wong; Robert Kamen; Daniel Tracey; Hamish Alien

1997-01-01

91

The regulation of cytochrome P450 2E1 during LPS-induced inflammation in the rat  

SciTech Connect

It is well known that inflammatory and infectious conditions differentially regulate cytochrome P450 (P450)-mediated drug metabolism in the liver. We have previously outlined a potential pathway for the downregulation in hepatic cytochrome P450 following LPS-mediated inflammation in the CNS (Abdulla, D., Goralski, K.B., Garcia Del Busto Cano, E., Renton, K.W., 2005. The signal transduction pathways involved in hepatic cytochrome P450 regulation in the rat during an LPS-induced model of CNS inflammation. Drug Metab. Dispos). The purpose of this study was to outline the effects of LPS-induced peripheral and central nervous system inflammation on hepatic cytochrome P450 2E1 (CYP2E1) in vivo, an enzyme that plays an important role in various physiological and pathological states. We report an increase in hepatic mRNA expression of CYP2E1 that occurred as early as 2-3 h following either the intraperitoneal (i.p.) injection of 5 mg/kg LPS or i.c.v. administration of 25 {mu}g of LPS. This increase in CYP2E1 mRNA expression was sustained for 24 h. In sharp contrast to the increase in hepatic CYP2E1 mRNA, we observed a significant reduction in the catalytic activity of this enzyme 24 h following either the i.c.v. or i.p. administration of LPS. Cycloheximide or actinomycin-D did not change the LPS-mediated downregulation in hepatic CYP2E1 catalytic activity. Our results support the idea that LPS acts at two different levels to regulate hepatic CYP2E1: a transcriptional level to increase CYP2E1 mRNA expression and a post-transcriptional level to regulate CYP2E1 protein and activity.

Abdulla, Dalya [Department of Pharmacology, Sir Charles Tupper Medical Bldg., Dalhousie University, Halifax, Nova Scotia, B3H 4H7 (Canada); Goralski, Kerry B. [Department of Pharmacology, Sir Charles Tupper Medical Bldg., Dalhousie University, Halifax, Nova Scotia, B3H 4H7 (Canada); College of Pharmacy, Burbidge Building, Dalhousie University, Halifax, Nova Scotia, B3H 3J5 (Canada); Renton, Kenneth W. [Department of Pharmacology, Sir Charles Tupper Medical Bldg., Dalhousie University, Halifax, Nova Scotia, B3H 4H7 (Canada)]. E-mail: Ken.Renton@dal.ca

2006-10-01

92

LPS-Induced Lung Inflammation in Marmoset Monkeys - An Acute Model for Anti-Inflammatory Drug Testing  

PubMed Central

Increasing incidence and substantial morbidity and mortality of respiratory diseases requires the development of new human-specific anti-inflammatory and disease-modifying therapeutics. Therefore, new predictive animal models that closely reflect human lung pathology are needed. In the current study, a tiered acute lipopolysaccharide (LPS)-induced inflammation model was established in marmoset monkeys (Callithrix jacchus) to reflect crucial features of inflammatory lung diseases. Firstly, in an ex vivo approach marmoset and, for the purposes of comparison, human precision-cut lung slices (PCLS) were stimulated with LPS in the presence or absence of the phosphodiesterase-4 (PDE4) inhibitor roflumilast. Pro-inflammatory cytokines including tumor necrosis factor-alpha (TNF-?) and macrophage inflammatory protein-1 beta (MIP-1?) were measured. The corticosteroid dexamethasone was used as treatment control. Secondly, in an in vivo approach marmosets were pre-treated with roflumilast or dexamethasone and unilaterally challenged with LPS. Ipsilateral bronchoalveolar lavage (BAL) was conducted 18 hours after LPS challenge. BAL fluid was processed and analyzed for neutrophils, TNF-?, and MIP-1?. TNF-? release in marmoset PCLS correlated significantly with human PCLS. Roflumilast treatment significantly reduced TNF-? secretion ex vivo in both species, with comparable half maximal inhibitory concentration (IC50). LPS instillation into marmoset lungs caused a profound inflammation as shown by neutrophilic influx and increased TNF-? and MIP-1? levels in BAL fluid. This inflammatory response was significantly suppressed by roflumilast and dexamethasone. The close similarity of marmoset and human lungs regarding LPS-induced inflammation and the significant anti-inflammatory effect of approved pharmaceuticals assess the suitability of marmoset monkeys to serve as a promising model for studying anti-inflammatory drugs.

Seehase, Sophie; Lauenstein, Hans-Dieter; Schlumbohm, Christina; Switalla, Simone; Neuhaus, Vanessa; Forster, Christine; Fieguth, Hans-Gerd; Pfennig, Olaf; Fuchs, Eberhard; Kaup, Franz-Josef; Bleyer, Martina; Hohlfeld, Jens M.; Braun, Armin

2012-01-01

93

LPS-Induced Murine Systemic Inflammation Is Driven by Parenchymal Cell Activation and Exclusively Predicted by Early MCP-1 Plasma Levels  

PubMed Central

Systemic inflammation remains a major cause of morbidity and mortality in the United States, across many disease processes. One classic murine model to study this syndrome is lipopolysaccharide (LPS)–induced Toll-like receptor 4 (TLR4)–dependent systemic inflammation. Although most studies have focused on inflammatory cell TLR4 responses, parenchymal cells also express TLR4. Our objective was to define the in vivo role of parenchymal- versus marrow-derived cell activation via TLR4 during LPS-induced inflammation. Mice bearing TLR4 on parenchymal cells only, marrow-derived cells only, both, or neither were generated using bone marrow transplantation. Mortality occurred only in mice that had TLR4 expression on their parenchymal cells. Before onset, virtually all major plasma cytokines and blood neutrophil responses were related to marrow-derived cell activation via TLR4. The only cytokine predictive of oncoming systemic inflammation was the chemokine monocyte chemoattractant protein-1. Late blood neutrophil responses were related to the presence of TLR4 on either parenchymal or marrow cells, whereas plasma cytokine elevations late in LPS-induced systemic inflammation were dependent on mice having TLR4 in both cell compartments. Parenchymal cell activation via TLR4 is a key component of LPS-induced systemic inflammation and mortality, although most plasma cytokine levels and blood neutrophil responses were not key components. Given its unique role, future studies into monocyte chemoattractant protein-1's exact role during systemic inflammation are warranted.

Juskewitch, Justin E.; Knudsen, Bruce E.; Platt, Jeffrey L.; Nath, Karl A.; Knutson, Keith L.; Brunn, Gregory J.; Grande, Joseph P.

2012-01-01

94

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

PubMed

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. PMID:23973924

Sabatino, María Eugenia; Sosa, Liliana Del Valle; Petiti, Juan Pablo; Mukdsi, Jorge Humberto; Mascanfroni, Iván Darío; Pellizas, Claudia Gabriela; Gutiérrez, Silvina; Torres, Alicia Inés; De Paul, Ana Lucía

2013-08-20

95

Protective effect of resveratrol against LPS-induced extracellular lipoperoxidation in AR42J cells partly via a Myd88-dependent signaling pathway.  

PubMed

Lipopolysaccharides (LPS) are major components of the cell wall of Gram negative bacteria implicated in the pathogenesis of bacterial infection. Resveratrol is a polyphenolic phytoalexin exhibiting antioxidant and anti-inflammatory properties. We investigated the protective effects of this natural compound on LPS-induced proinflammatory effect using non-myeloid AR42J pancreatic cells. We found that LPS dose-dependently increased extracellular malondialdehyde (MDA) and nitric oxide without affecting their intracellular level whereas resveratrol abolished all these deleterious effects. LPS increased CD14 expression; IRAK1 and a phosphorylated form of p38 MAPK protein. Resveratrol counteracted LPS effect by decreasing CD14 and IRAK1 expression but unexpectedly increased the p38 MAPK protein phosphorylation. Altogether, our data highlighted the functionality of the TLR4-Myd88 signaling pathway in LPS pro-oxidant effect using non-myeloid cells. They further suggested that resveratrol exerted antioxidant properties either by a Myd88-dependent way not involving IRAK1 or by a TRIF dependent pathway. PMID:20035708

Sebai, Hichem; Ristorcelli, Elodie; Sbarra, Veronique; Hovsepian, Sonia; Fayet, Guy; Aouani, Ezzedine; Lombardo, Dominique

2009-12-24

96

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

97

Ketamine\\/Xylazine attenuates LPS-induced iNOS expression in various rat tissues 1,2 1 Presented at the annual meeting of the Association of Academic Surgery, Boston, MA, November 7–9, 2002. 2 Supported by NIGMS grant GM38529 and GM08792  

Microsoft Academic Search

Ketamine and xylazine (K\\/X) are commonly used in combination as an anesthetic agent in experimental animal models. We previously noted that K\\/X attenuated lipopolysaccharide (LPS)-induced liver injury, gastric stasis, and reduced symptoms of endotoxemia. Because ketamine attenuates expression of several proinflammatory genes, we examined the effects of K\\/X on inducible nitric oxide synthase (iNOS), which has been implicated in endotoxin-induced

Kenneth S Helmer; Yan Cui; Ashvin Dewan; David W Mercer

2003-01-01

98

Anti-inflammatory effects of oleanolic acid on LPS-induced inflammation in vitro and in vivo.  

PubMed

Oleanolic acid (OA) is a triterpenoid known for its anti-inflammatory and anti-cancer properties; however, the anti-inflammatory effects of OA on lipopolysaccharide (LPS)-mediated pro-inflammatory responses have not been studied. Here, we first investigated the possible anti-inflammatory effects of OA against pro-inflammatory responses in human umbilical vein endothelial cells (HUVECs) induced by LPS and the associated signaling pathways. We found that OA inhibited LPS-induced barrier disruption, expression of cell adhesion molecules (CAMs), and adhesion/transendothelial migration of monocytes to HUVECs. OA also suppressed acetic acid-induced hyperpermeability and carboxymethylcellulose-induced leukocyte migration in vivo. Further studies revealed that OA suppressed the production of tumor necrosis factor-? and activation of nuclear factor-?B by LPS. Collectively, these results suggest that OA has anti-inflammatory effects by inhibiting hyperpermeability, the expression of CAMs, and the adhesion and migration of leukocytes, thereby endorsing its usefulness as a therapeutic agent for vascular inflammatory diseases. PMID:22875543

Lee, Wonhwa; Yang, Eun-Ju; Ku, Sae-Kwang; Song, Kyung-Sik; Bae, Jong-Sup

2013-02-01

99

Effects of (60)Co gamma -rays on PWM and LPS Induced Lymphocytes.  

National Technical Information Service (NTIS)

The relationship between lymphocytes induced by PWM and LPS was investigated by means of (3)H-TdR and (14)C-UR incorporation. The study showed that in vitro, PWM-induced cells were able to promote the stimulating effect of LPS to B lymphocyte. The stimula...

L. Su F. Liu K. Liu C. Xu Yu Zhiying

1987-01-01

100

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...

101

GuaLou GuiZhi decoction inhibits LPS-induced microglial cell motility through the MAPK signaling pathway.  

PubMed

Microglial activation plays an important role in neroinflammation following ischemic stroke. Activated microglial cells can then migrate to the site of injury to proliferate and release substances which induce secondary brain damage. It has been shown that microglial migration is associated with the activation of the mitogen-activated protein kinase (MAPK) signaling pathways. The Chinese formula, GuaLou GuiZhi decoction (GLGZD), has long been administered in clinical practice for the treatment of post-stroke disabilities, such as muscular spasticity. In a previous study, we demonstrated that the anti-inflammtory effects of GLGZD were mediated by the TLR4/NF-?B pathway in lipopolysaccharide (LPS)-stimulated microglial cells. Therefore, in this study, we evaluated the role of GLGZD in microglial migration by performing scratch wound assays and migration assays. We wished to elucidate the cellular and molecular mechanisms elicited by this TCM formula in microglial-induced inflammation by evaluating the release and expression of chemotactic cytokines [monocyte chemo-attractant protein-1 (MCP-1), macrophage inflammatory protein-1? (MIP-1?) and interleukin (IL)-8] by ELISA and quantitative PCR. Our results revealed that the migration of microglial cells was enhanced in the presence of LPS (100 ng/ml); however, GLGZD (100 µg/ml) significantly inhibited cell motility and the production of chemokines through the inhibition of the activation of the p38 and c-Jun N-terminal protein kinase (JNK) signaling pathway. We demonstrate the potential of GLGZD in the modulation of microglial motility by investigating the effects of GLGZD on microglial migration induced by LPS. Taken together, our data suggest that GLGZD per se cannot trigger microglial motility, whereas GLGZD impedes LPS-induced microglial migration through the activation of the MAPK signaling pathway. These results provide further evidence of the anti-inflammatory effects of GLGZD and its potential for use in the treatment of ischemic stroke. PMID:24127065

Hu, Haixia; Li, Zuanfang; Zhu, Xiaoqin; Lin, Ruhui; Peng, Jun; Tao, Jing; Chen, Lidian

2013-10-11

102

Effect of Sup 60 Co gamma Rays on Con A and LPS Induced Lymphocytes.  

National Technical Information Service (NTIS)

The effect of /sup 60/Co gamma -rays on lymphocytes induced by Con A and LPS and the relationship between these two groups of cells were investigated by means of /sup 3/H-TdR incorporation. The study showed that in vitro, Con A cells were able to promote ...

Su L. Liu K. Ma X

1987-01-01

103

Role of macrophages in LPS-induced osteoblast and PDL cell apoptosis  

Microsoft Academic Search

In periradicular lesions and periodontal disease, bacterial invasion leads to chronic inflammation resulting in disruption of the structural integrity of the periodontal ligament and progressive alveolar bone destruction. The pathogenesis of these conditions has been attributed not only to bacterial-induced tissue destruction but also to a defect in periodontal tissue repair. Accumulated data have also shown that lipopolysaccharide (LPS) can

Kewalin Thammasitboon; Steven R. Goldring; Jason A. Boch

2006-01-01

104

The influence of temperament on lipopolysaccharide (LPS) induced secretion of epinephrine and cortisol in bulls.  

Technology Transfer Automated Retrieval System (TEKTRAN)

The host's complex reaction to a pathogenic stressor involves interaction of the neural, endocrine, and immune systems. For example, exposure to bacteria stimulates secretion of the stress-related hormones, cortisol (CS) and epinephrine (Epi; 1). Innate and induced secretion of CS and Epi are influe...

105

Protection against LPS-Induced Pulmonary Edema through the Attenuation of Protein Tyrosine Phosphatase-1B Oxidation  

PubMed Central

One hallmark of acute lung injury is the disruption of the pulmonary endothelial barrier. Such disruption correlates with increased endothelial permeability, partly through the disruption of cell–cell contacts. Protein tyrosine phosphatases (PTPs) are known to affect the stability of both cell–extracellular matrix adhesions and intercellular adherens junctions (AJs). However, evidence for the role of select PTPs in regulating endothelial permeability is limited. Our investigations noted that the inhibition of PTP1B in cultured pulmonary endothelial cells (ECs), as well as in the vasculature of intact murine lungs via the transient overexpression of a catalytically inactive PTP1B, decreased the baseline resistance of cultured EC monolayers and increased the formation of edema in murine lungs, respectively. In addition, we observed that the overexpression of wild-type PTP1B enhanced basal barrier function in vitro. Immunohistochemical analyses of pulmonary ECs and the coimmunoprecipitation of murine lung homogenates demonstrated the association of PTP1B with the AJ proteins ?-catenin, p120-catenin, and VE-cadherin both in vitro and ex vivo. Using LPS in a model of sepsis-induced acute lung injury, we showed that reactive oxygen species were generated in response to LPS, which correlated with enhanced PTP1B oxidation, inhibited phosphatase activity, and attenuation of the interactions between PTP1B and ?-catenin, as well as enhanced ?-catenin tyrosine phosphorylation. Finally, the overexpression of a cytosolic PTP1B fragment, shown to be resistant to nicotinamide adenine dinucleotide phosphate–reduced oxidase–4 (Nox4)-mediated oxidation, significantly attenuated LPS-induced endothelial barrier dysfunction and the formation of lung edema, and preserved the associations of PTP1B with AJ protein components, independent of PTP1B phosphatase activity. We conclude that PTP1B plays an important role in maintaining the pulmonary endothelial barrier, and PTP1B oxidation appears to contribute to sepsis-induced pulmonary vascular dysfunction, possibly through the disruption of AJs.

Grinnell, Katie L.; Chichger, Havovi; Braza, Julie; Duong, Huetran

2012-01-01

106

Role of JNK and NF??B pathways in Porphyromonas gingivalis LPS?induced vascular cell adhesion molecule?1 expression in human aortic endothelial cells.  

PubMed

An increasing number of studies have shown a correlation between Porphyromonas gingivalis (P. gingivalis) infection and atherosclerosis. A recent study demonstrated that the expression of vascular cell adhesion molecule?1 (VCAM?1) was induced by P. gingivalis lipopolysaccharide (LPS) in human aortic endothelial cells (HAECs). The activation of p38 mitogen?activated protein kinase (p38 MAPK) was at least partially involved in this process. Those results suggested the potential involvement of P. gingivalis LPS in the pathogenesis of atherosclerosis. However, the mechanism involved in P. gingivalis LPS?induced VCAM?1 production has not yet been elucidated. The present study examined the role of the c?Jun N?terminal kinase (JNK) and nuclear factor??B (NF??B) cell signaling pathways in P. gingivalis LPS?induced VCAM?1 expression in HAECs. Western blotting was used to investigate the activation of JNK and NF??B pathways in HAECs exposed to P. gingivalis LPS. Following this, specific pharmacological inhibitors were introduced and the protein production of VCAM?1 was studied. The results showed that the JNK and NF??B pathways in HAECs were capable of being activated by P. gingivalis LPS. The inhibition of NF??B by SN50 significantly attenuated P. gingivalis LPS?induced VCAM?1 expression, while the inhibition of JNK by SP600125 enhanced VCAM?1 expression in P. gingivalis LPS?treated HAECs. Therefore, the results indicated that NF??B was essential for the P. gingivalis LPS?induced VCAM?1 expression in HAECs and that JNK may be a suppressor of VCAM?1 expression in HAECs. PMID:24045414

Liu, Bin; Wang, Jia; Cheng, Lan; Liang, Jingping

2013-09-17

107

B and T lymphocyte attenuator inhibits LPS-induced endotoxic shock by suppressing Toll-like receptor 4 signaling in innate immune cells  

PubMed Central

Although innate immune responses are necessary for the initiation of acquired immune responses and the subsequent successful elimination of pathogens, excessive responses occasionally result in lethal endotoxic shock accompanied by a cytokine storm. B and T lymphocyte attenuator (BTLA), a coinhibitory receptor with similarities to cytotoxic T-lymphocyte antigen (CTLA)-4 and programmed death (PD)-1, is expressed in not only B and T cells but also dendritic cells (DCs) and macrophages (M?s). Recently, several studies have reported that BTLA-deficient (BTLA?/?) mice show enhanced pathogen clearance compared with WT mice in early phase of infections. However, the roles of BTLA expressed on innate cells in overwhelming and uncontrolled immune responses remain unclear. Here, we found that BTLA?/? mice were highly susceptible to LPS-induced endotoxic shock. LPS-induced TNF-? and IL-12 production in DCs and M?s was significantly enhanced in BTLA?/? mice. BTLA?/? DCs also produced high levels of TNF-? on stimulation with Pam3CSK4 but not poly(I:C) or CpG, suggesting that BTLA functions as an inhibitory molecule on Toll-like receptor signaling at cell surface but not endosome. Moreover, BTLA?/? DCs showed enhanced MyD88- and toll/IL-1R domain-containing adaptor inducing IFN (TRIF)-dependent signaling on LPS stimulation, which is associated with impaired accumulation of Src homology 2-containing protein tyrosine phosphatase in lipid rafts. Finally, we found that an agonistic anti-BTLA antibody rescued mice from LPS-induced endotoxic shock, even if the antibody was given to mice that had developed a sign of endotoxic shock. These results suggest that BTLA directly inhibits LPS responses in DCs and M?s and that agonistic agents for BTLA might have therapeutic potential for LPS-induced endotoxic shock.

Kobayashi, Yoshihisa; Iwata, Arifumi; Suzuki, Kotaro; Suto, Akira; Kawashima, Saki; Saito, Yukari; Owada, Takayoshi; Kobayashi, Midori; Watanabe, Norihiko; Nakajima, Hiroshi

2013-01-01

108

[The effect of yeast glycans in experimental LPS-induced endotoxicosis].  

PubMed

The immunomodulating action of yeast glycans obtained from Rhodotorula rubra (rhonasan) and Sporobolomyces albo-rubescens (heteroglycan Sp-50) was studied under the conditions of experimental endotoxicosis in mice, induced by the injection of the sublethal dose of Escherichia coli lipopolysaccharide (LPS). In endotoxicosis glycans produced a protective effect, depending on the time of injection. The study demonstrated that after the injection of glycans the survival rate of the animals increased and the LPS-inhibited function of peritoneal macrophages and B lymphocytes was completely or partially restored. PMID:10876900

Gurina, S V; Fedorova, L G

109

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

110

LPS-induced release of IL-6 from glia modulates production of IL-1? in a JAK2-dependent manner  

PubMed Central

Background Compelling evidence has implicated neuroinflammation in the pathogenesis of a number of neurodegenerative conditions. Chronic activation of both astrocytes and microglia leads to excessive secretion of proinflammatory molecules such as TNF?, IL-6 and IL-1? with potentially deleterious consequences for neuronal viability. Many signaling pathways involving the mitogen-activated protein kinases (MAPKs), nuclear factor ?B (NF?B) complex and the Janus kinases (JAKs)/signal transducers and activators of transcription (STAT)-1 have been implicated in the secretion of proinflammatory cytokines from glia. We sought to identify signaling kinases responsible for cytokine production and to delineate the complex interactions which govern time-related responses to lipopolysaccharide (LPS). Methods We examined the time-related changes in certain signaling events and the release of proinflammatory cytokines from LPS-stimulated co-cultures of astrocytes and microglia isolated from neonatal rats. Results TNF? was detected in the supernatant approximately 1 to 2 hours after LPS treatment while IL-1? and IL-6 were detected after 2 to 3 and 4 to 6 hours, respectively. Interestingly, activation of NF?B signaling preceded release of all cytokines while phosphorylation of STAT1 was evident only after 2 hours, indicating that activation of JAK/STAT may be important in the up-regulation of IL-6 production. Additionally, incubation of glia with TNF? induced both phosphorylation of JAK2 and STAT1 and the interaction of JAK2 with the TNF? receptor (TNFR1). Co-treatment of glia with LPS and recombinant IL-6 protein attenuated the LPS-induced release of both TNF? and IL-1? while potentiating the effect of LPS on suppressor of cytokine signaling (SOCS)3 expression and IL-10 release. Conclusions These data indicate that TNF? may regulate IL-6 production through activation of JAK/STAT signaling and that the subsequent production of IL-6 may impact on the release of TNF?, IL-1? and IL-10.

2012-01-01

111

Effect of a novel leukotoriene synthesis inhibitor, BAY x1005, on the antigen- and LPS-induced airway hyperresponsiveness in guinea pigs  

Microsoft Academic Search

Due to the inhibition of 5-lipoxygenase-activating protein (FLAP), BAY x1005 is a new selective inhibitor of leukotriene synthesis. The effects of BAY x1005 on the antigen- and bacterial lipopolysaccharide (LPS)-induced airway hyperresponsiveness in guinea pigs were investigated. Six times provocation of aeroantigen caused biphasic increases in airway resistance which peaked at 1 hr (immediate phase reaction) and 4 hrs (late

Hiroichi Nagai; Hiroshi Takeda; Takashi Uno; Hiroyuki Tanaka; Akihiko Matsuo

1996-01-01

112

Genomic instability in liver cells caused by an LPS-induced bystander-like effect.  

PubMed

Bacterial infection has been linked to carcinogenesis, however, there is lack of knowledge of molecular mechanisms that associate infection with the development of cancer. We analyzed possible effects of the consumption of heat-killed E. coli O157:H7 cells or its cellular components, DNA, RNA, protein or lipopolysaccharides (LPS) on gene expression in naďve liver cells. Four week old mice were provided water supplemented with whole heat-killed bacteria or bacterial components for a two week period. One group of animals was sacrificed immediately, whereas another group was allowed to consume uncontaminated tap water for an additional two weeks, and liver samples were collected, post mortem. Liver cells responded to exposure of whole heat-killed bacteria and LPS with alteration in ?H2AX levels and levels of proteins involved in proliferation, DNA methylation (MeCP2, DNMT1, DNMT3A and 3B) or DNA repair (APE1 and KU70) as well as with changes in the expression of genes involved in stress response, cell cycle control and bile acid biosynthesis. Other bacterial components analysed in this study did not lead to any significant changes in the tested molecular parameters. This study suggests that lipopolysaccharides are a major component of Gram-negative bacteria that induce molecular changes within naďve cells of the host. PMID:23874414

Kovalchuk, Igor; Walz, Paul; Thomas, James; Kovalchuk, Olga

2013-07-09

113

Genomic Instability in Liver Cells Caused by an LPS-Induced Bystander-Like Effect  

PubMed Central

Bacterial infection has been linked to carcinogenesis, however, there is lack of knowledge of molecular mechanisms that associate infection with the development of cancer. We analyzed possible effects of the consumption of heat-killed E. coli O157:H7 cells or its cellular components, DNA, RNA, protein or lipopolysaccharides (LPS) on gene expression in naďve liver cells. Four week old mice were provided water supplemented with whole heat-killed bacteria or bacterial components for a two week period. One group of animals was sacrificed immediately, whereas another group was allowed to consume uncontaminated tap water for an additional two weeks, and liver samples were collected, post mortem. Liver cells responded to exposure of whole heat-killed bacteria and LPS with alteration in ?H2AX levels and levels of proteins involved in proliferation, DNA methylation (MeCP2, DNMT1, DNMT3A and 3B) or DNA repair (APE1 and KU70) as well as with changes in the expression of genes involved in stress response, cell cycle control and bile acid biosynthesis. Other bacterial components analysed in this study did not lead to any significant changes in the tested molecular parameters. This study suggests that lipopolysaccharides are a major component of Gram-negative bacteria that induce molecular changes within naďve cells of the host.

Kovalchuk, Igor; Walz, Paul; Thomas, James; Kovalchuk, Olga

2013-01-01

114

LPS Induces Greater Bone and PDL Loss in SPARC-null Mice  

PubMed Central

Individuals with periodontal disease have increased risk of tooth loss, particularly in cases with associated loss of alveolar bone and periodontal ligament (PDL). Current treatments do not predictably regenerate damaged PDL. Collagen I is the primary component of bone and PDL extracellular matrix. SPARC/Osteonectin (SP/ON) is implicated in the regulation of collagen content in healthy PDL. In this study, periodontal disease was induced by injections of lipopolysaccharide (LPS) from Aggregatibacter actinomycetemcomitans in wild-type (WT) and SP/ON-null C57/Bl6 mice. A 20-µg quantity of LPS was injected between the first and second molars 3 times a week for 4 weeks, whereas PBS control was injected into the contralateral maxilla. LPS injection resulted in a significant decrease in bone volume fraction in both genotypes; however, significantly greater bone loss was detected in SP/ON-null maxilla. SP/ON-null PDL exhibited more extensive degradation of connective tissue in the gingival tissues. Although total cell numbers in the PDL of SP/ON-null were not different from those in WT, the inflammatory infiltrate was reduced in SP/ON-null PDL. Histology of collagen fibers revealed marked reductions in collagen volume fraction and in thick collagen volume fraction in the PDL of SP/ON-null mice. SP/ON protects collagen content in PDL and in alveolar bone in experimental periodontal disease.

Trombetta-eSilva, J.; Yu, H.; Arias, D.N.; Rossa, C.; Kirkwood, K.L.; Bradshaw, A.D.

2011-01-01

115

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

116

Rhizoma Coptidis Inhibits LPS-Induced MCP-1/CCL2 Production in Murine Macrophages via an AP-1 and NF?B-Dependent Pathway  

PubMed Central

Introduction. The Chinese extract Rhizoma coptidis is well known for its anti-inflammatory, antioxidative, antiviral, and antimicrobial activity. The exact mechanisms of action are not fully understood. Methods. We examined the effect of the extract and its main compound, berberine, on LPS-induced inflammatory activity in a murine macrophage cell line. RAW 264.7 cells were stimulated with LPS and incubated with either Rhizoma coptidis extract or berberine. Activation of AP-1 and NF?B was analyzed in nuclear extracts, secretion of MCP-1/CCL2 was measured in supernatants. Results. Incubation with Rhizoma coptidis and berberine strongly inhibited LPS-induced monocyte chemoattractant protein (MCP)-1 production in RAW cells. Activation of the transcription factors AP-1 and NF?B was inhibited by Rhizoma coptidis in a dose- and time-dependent fashion. Conclusions. Rhizoma coptidis extract inhibits LPS-induced MCP-1/CCL2 production in vitro via an AP-1 and NF?B-dependent pathway. Anti-inflammatory action of the extract is mediated mainly by its alkaloid compound berberine.

Remppis, Andrew; Bea, Florian; Greten, Henry Johannes; Buttler, Annette; Wang, Hongjie; Zhou, Qianxing; Preusch, Michael R.; Enk, Ronny; Ehehalt, Robert; Katus, Hugo; Blessing, Erwin

2010-01-01

117

Neuroprotective effects of pretreatment with propofol in LPS-induced BV-2 microglia cells: role of TLR4 and GSK-3?.  

PubMed

Surgery often leads to neuroinflammation, which mainly acts as the activation of microglia cells. Propofol is always used for induction and maintenance of anesthesia prior to surgical trauma, whereas whether or not it could attenuate neuroinflammation used prophylactically is not well defined. In the present study, we incubated BV-2 microglia cells with 1 ?g/ml lipopolysaccharide (LPS) to mimic neuroinflammation in vitro. Firstly, cell viability was measured using 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and the data indicated that propofol would not reduce cell viability unless its concentration reached 300 ?M. Secondly, BV-2 microglia cells were pretreated with 30 ?M propofol (clinically relevant concentration), and then stimulated with LPS. The results showed that the production of tumor necrosis factor-? (TNF-?), interleukin (IL)-1? and IL-10 was considerably increased by LPS, but the change could be markedly attenuated by pretreatment with propofol. Meanwhile, pretreatment with propofol inhibited LPS-induced augmentation of toll-like receptor 4 (TLR4) expression at both mRNA and protein levels and further upregulated LPS-induced inactivation of glycogen synthase kinase-3? (GSK-3?) in BV-2 microglia cells. These results indicated, at least in part, that pretreatment with propofol can protect BV-2 microglia cells against LPS-induced inflammation. Downregulation of TLR4 expression and inactivation of GSK-3? may be involved in its protective effect. PMID:22588329

Gui, Bo; Su, Mingyan; Chen, Jie; Jin, Lai; Wan, Rong; Qian, Yanning

2012-10-01

118

LPS-induced oxidative stress and inflammatory reaction in the rat striatum.  

PubMed

Background: Inflammation-induced microglia activation and increased oxidative stress have been observed in neurodegenerative disorders, such as Parkinson's disease. The aim of our study was to determine the appropriate dose and route of LPS administration to study hydroxyl radical generation and extracellular level of dopamine (DA), glutamate (GLU) and adenosine (ADN) in the rat striatum as markers of DA neuron damage and glial cell activation. The effect of LPS administration on DA, DOPAC, HVA and hydroxyl radical tissue level was also examined. Methods: LPS was given to rats in a single dose of 10 mg/kg ip, repeatedly for 5 days in a dose of 5 mg/kg ip and intrastriatally at doses 5, 20 and 40 ?g/4 ?l. The extracellular level of DA, hydroxyl radical, ADN and GLU were assayed in striatal dialysates using HPLC with electrochemical, fluorescence and VIS detection, respectively. Results: Asingle ip LPS (10 mg/kg) administration increased hydroxyl radical production but did not affect extracellular DA, GLU and ADN level. Repeated ip LPS (5 x 5 mg/kg) treatment decreased extracellular level of DA, GLU, ADN and production of hydroxyl radical. LPS (5 and 10 ?g) given intrastriatally increased hydroxyl radical production, extracellular GLU and ADN level from 0 to 180 min after administration, but did not influence DA level. LPS (5, 20 and 40 ?g) decreased striatal DA and DOPAC content, but increased HVA and hydroxyl radical level 72 h after intrastriatal administration. Conclusions: Our data indicate that local intrastriatal LPS administration activates glial cells and increases production of free radicals and secretion of GLU and ADN in early phase of inflammation. The damage of DA neurons is observed 72 h after local LPS administration. PMID:24145080

Noworyta-Soko?owska, Karolina; Górska, Anna; Go?embiowska, Krystyna

2013-01-01

119

Cloning and analysis of gene regulation of a novel LPS-inducible cDNA  

SciTech Connect

The expression of many genes is altered upon the activation of macrophages by bacterial LPS. These genes play a crucial role in the orchestration of various responses to protect the host against infection. A novel 2.3 kilobase (kb) cDNA, designated IRG1, was obtained from a cDNA library prepared with RNA isolated from RAW 264.7 following lipopolysaccharide stimulation. Sequence analysis of the clone revealed no identity to any known genes but showed the presence of many potential phosphorylation sites suggesting that IRG1 protein product may be regulated at this level. Furthermore, IRG1 contains the motif for glycosaminoglycan attachment site, implying that IRG1 may be a proteoglycan. By interspecific backcross analysis, IRG1 was mapped to mouse chromosome 14 linked to Tyrp2 and Rap2a. The IRG1 message appears 1.5 h following LPS exposure and its induction was not dependent on new protein synthesis. In fact, cycloheximide induced the expression of IRG1, suggesting that a protein repressor prevents the expression of IRG1 when uninduced. The role of the protein kinase A pathway in regulating the induction of IRG1 by LPS is questionable, because although forskolin inhibited its induction, neither dibutyrl-cAMP nor 8-(4-chlorophenylthio)-cAMP had much effect on its expression. In contrast, activation of protein kinase C potentiated the LPS response. Chelation of extracellular calcium inhibited IRG1 4 h after LPS induction, while increasing intracellular calcium had little effect on the levels of the IRG1 transcript. Inhibiting tyrosine phosphorylation abrogated the induction of IRG1 by LPS. Hence, the induction of IRG1 by LPS is mediated by tyrosine kinase and protein kinase C pathway. 80 refs., 5 figs.

Lee, C.G.L.; O`Brien, W.E. [Baylor College of Medicine, Houston, TX (United States); Jenkins, N.A.; Gilbert, D.J.; Copeland, N.G. [Frederick Cancer Research and Development Center, MD (United States)

1995-03-01

120

Interleukin1? System (Ligand, Receptor Type I, Receptor Accessory Protein and Receptor Antagonist), TNF-?, TGF-?1 and Neuropeptide Y mRNAs in Specific Brain Regions During Bacterial LPS-Induced Anorexia  

Microsoft Academic Search

Bacterial lipopolysaccharide (LPS) or endotoxin induces neurological manifestations including anorexia. It is proposed that LPS-induced cytokine production is involved in the generation of neurological manifestations and in neuroinflammatory\\/immunological responses during Gram-negative infections. For example, LPS-induced effects can be blocked or ameliorated by the interleukin-1 receptor antagonist (IL-1Ra). Here, sensitive and specific RNase protection assays were used to investigate the effects

Sergey E Ilyin; Dave Gayle; Mark C Flynn; Carlos R Plata-Salamán

1998-01-01

121

IL1beta- and LPS-induced serotonin secretion is increased in EC cells derived from Crohn's disease.  

PubMed

Gut mucosal enterochromaffin (EC) cells are regarded as key regulators of intestinal motility and fluid secretion via secretion of serotonin (5HT), are increased in numbers in mucosal inflammation and located in close proximity to immune cells. We examined whether interleukin (IL)1beta and Escherichia coli lipopolysaccharide (LPS) induced EC cell 5HT release through Toll-like/IL-1 (TIL) receptor activation, nuclear factor kappa B (NFkappaB) and mitogen-activated protein kinase (MAPK) phosphorylation and evaluated whether somatostatin could inhibit this phenomenon. Pure (>98%) human intestinal EC cells were isolated by fluorescent activated cell sorting from preparations of normal (n = 5) and Crohn's colitis (n = 6) mucosa. 5HT release was measured (ELISA), and NFkappaB and ERK phosphorylation quantitated (ELISA) in response to IL1beta and LPS. 5HT secretion was increased by both E. coli LPS (EC(50) = 5 ng mL(-1)) and IL1beta (EC(50) = 0.05 pmol L(-1)) >2-fold (P < 0.05) in Crohn's EC cells compared with normal EC cells. Secretion was reversible by the TLR4 antagonist, E. coli K12 LPS (IC(50) = 12 ng mL(-1)) and the IL1beta receptor antagonist (ILRA; IC(50) = 3.4 ng mL(-1)). IL1beta caused significant (P < 0.05) NFkappaB and MAPK phosphorylation (40-55%). The somatostatin analogue, lanreotide inhibited IL1beta-stimulated secretion in Crohn's (IC(50) = 0.61 nmol L(-1)) and normal EC cells (IC(50) = 1.8 nmol L(-1)). Interleukins (IL1beta) and bacterial products (E. coli LPS) stimulated 5HT secretion from Crohn's EC cells via TIL receptor activation (TLR4 and IL1beta). Immune-mediated alterations in EC cell secretion of 5HT may represent a component of the pathogenesis of abnormal bowel function in Crohn's disease. Inhibition of EC cell-mediated 5HT secretion may be an alternative therapeutic strategy in the amelioration of inflammatory bowel disease symptomatology. PMID:19019013

Kidd, M; Gustafsson, B I; Drozdov, I; Modlin, I M

2008-10-25

122

Baicalein inhibits nuclear factor-?B and apoptosis via c-FLIP and MAPK in d-GalN\\/LPS induced acute liver failure in murine models  

Microsoft Academic Search

The hepatoprotective effects and molecular mechanisms of baicalein on acute liver failure induced by d-galactosamine (d-GalN)\\/lipopolysaccharides (LPS) were investigated in vivo. Mice were administered with different doses of baicalein (50, 100 or 150mg\\/kg, p.o.) 1h before injection of d-GalN (700mg\\/kg)\\/LPS (10?g\\/kg) and then sacrificed 6h after treatment with d-GalN\\/LPS. Pretreatment with baicalein prevented d-GalN\\/LPS-induced liver damage by preventing associated increases

Yan-Ling Wu; Li-Hua Lian; Ying Wan; Ji-Xing Nan

2010-01-01

123

Phillyrin attenuates LPS-induced pulmonary inflammation via suppression of MAPK and NF-?B activation in acute lung injury mice.  

PubMed

Phillyrin (Phil) is one of the main chemical constituents of Forsythia suspensa (Thunb.), which has shown to be an important traditional Chinese medicine. We tested the hypothesis that Phil modulates pulmonary inflammation in an ALI model induced by LPS. Male BALB/c mice were pretreated with or without Phil before respiratory administration with LPS, and pretreated with dexamethasone as a control. Cytokine release (TNF-?, IL-1?, and IL-6) and amounts of inflammatory cell in bronchoalveolar lavage fluid (BALF) were detected by ELISA and cell counting separately. Pathologic changes, including neutrophil infiltration, interstitial edema, hemorrhage, hyaline membrane formation, necrosis, and congestion during acute lung injury in mice were evaluated via pathological section with HE staining. To further investigate the mechanism of Phil anti-inflammatory effects, activation of MAPK and NF-?B pathways was tested by western blot assay. Phil pretreatment significantly attenuated LPS-induced pulmonary histopathologic changes, alveolar hemorrhage, and neutrophil infiltration. The lung wet-to-dry weight ratios, as the index of pulmonary edema, were markedly decreased by Phil pretreatment. In addition, Phil decreased the production of the proinflammatory cytokines including (TNF-?, IL-1?, and IL-6) and the concentration of myeloperoxidase (MPO) in lung tissues. Phil pretreatment also significantly suppressed LPS-induced activation of MAPK and NF-?B pathways in lung tissues. Taken together, the results suggest that Phil may have a protective effect on LPS-induced ALI, and it potentially contributes to the suppression of the activation of MAPK and NF-?B pathways. Phil may be a new preventive agent of ALI in the clinical setting. PMID:23751215

Zhong, Wei-Ting; Wu, Yi-Chun; Xie, Xian-Xing; Zhou, Xuan; Wei, Miao-Miao; Soromou, Lanan-Wassy; Ci, Xin-Xin; Wang, Da-Cheng

2013-06-07

124

GM-CSF increases LPS-induced production of proinflammatory mediators via upregulation of TLR4 and CD14 in murine microglia  

PubMed Central

Background Microglia are resident macrophage-like cells in the central nervous system (CNS) and cause innate immune responses via the LPS receptors, Toll-like receptor (TLR) 4 and CD14, in a variety of neuroinflammatory disorders including bacterial infection, Alzheimer’s disease, and amyotrophic lateral sclerosis. Granulocyte macrophage-colony stimulating factor (GM-CSF) activates microglia and induces inflammatory responses via binding to GM-CSF receptor complex composed of two different subunit GM-CSF receptor ? (GM-CSFR?) and common ? chain (?c). GM-CSF has been shown to be associated with neuroinflammatory responses in multiple sclerosis and Alzheimer’s disease. However, the mechanisms how GM-CSF promotes neuroinflammation still remain unclear. Methods Microglia were stimulated with 20 ng/ml GM-CSF and the levels of TLR4 and CD14 expression were evaluated by RT-PCR and flowcytometry. LPS binding was analyzed by flowcytometry. GM-CSF receptor complex was analyzed by immunocytechemistry. The levels of IL-1?, IL-6 and TNF-? in culture supernatant of GM-CSF-stimulated microglia and NF-?B nuclear translocation were determined by ELISA. Production of nitric oxide (NO) was measured by the Griess method. The levels of p-ERK1/2, ERK1/2, p-p38 and p38 were assessed by Western blotting. Statistically significant differences between experimental groups were determined by one-way ANOVA followed by Tukey test for multiple comparisons. Results GM-CSF receptor complex was expressed in microglia. GM-CSF enhanced TLR4 and CD14 expressions in microglia and subsequent LPS-binding to the cell surface. In addition, GM-CSF priming increased LPS-induced NF-?B nuclear translocation and production of IL-1?, IL-6, TNF-? and NO by microglia. GM-CSF upregulated the levels of p-ERK1/2 and p-p38, suggesting that induction of TLR4 and CD14 expression by GM-CSF was mediated through ERK1/2 and p38, respectively. Conclusions These results suggest that GM-CSF upregulates TLR4 and CD14 expression in microglia through ERK1/2 and p38, respectively, and thus promotes the LPS receptor-mediated inflammation in the CNS.

2012-01-01

125

Effect of Rabbit Epididymal Antimicrobial Peptide, REHb?P, on LPS-Induced Proinflammatory Cytokine Responses in Human Vaginal Cells In Vitro  

PubMed Central

Antimicrobial peptides (AMP's) protect epithelial surfaces including epididymis against pathogens and play a key role in orchestrating various defensive responses. Recently, we have identified one such AMP, rabbit epididymal hemoglobin-? subuit (REHb?P) from the epididymal fluid of rabbit, Oryctologus cuniculus. The demonstration of a protective role of REHb?P in epididymal epithelial cells (EPEC's) led us to investigate: (1) the identification of LPS interactive domain in REHb?P, and (2) whether the REHb?P of rabbit origin mediates vaginal cellular immune responses of another species (human). HeLa-S3, human vaginal epithelial cells (hVECs) were exposed to LPS or the LPS-stimulated cells treated with REHb?P or neutral peptide, nREHb?P. Effect of LPS and cytokines (IL-6 and IL-1?) and chemokines (IL-8, MCP-1) levels was determined in the culture supernatants. In response to the LPS, hVECs synthesized these mediators and the levels were significantly higher than controls. This enhancing effect was ameliorated when the LPS-induced hVECs were treated with REHb?P. Similar results were obtained on NF-?B protein and hBD-1 mRNA expression. Confocal microscopy studies revealed that REHb?P attenuated the LPS-induced internalization of E. coli by macrophages. The chemotaxis studies performed using Boyden chamber Transwell assay, which showed elevated migration of U937 cells when the supernatants of LPS-induced hVECs were used, and the effect was inhibited by REHb?P. REHb?P was found to be localized on the acrosome of rabbit spermatozoa, suggesting its role in sperm protection beside sperm function. In conclusion, REHb?P may have the potential to develop as a therapeutic agent for reproductive tract infections (RTI's).

Reddy, K. V. R.; Sukanya, D.; Patgaonkar, M. S.; Selvaakumar, C.

2012-01-01

126

Mechanical ventilation with high tidal volumes attenuates myocardial dysfunction by decreasing cardiac edema in a rat model of LPS-induced peritonitis  

PubMed Central

Background Injurious mechanical ventilation (MV) may augment organ injury remote from the lungs. During sepsis, myocardial dysfunction is common and increased endothelial activation and permeability can cause myocardial edema, which may, among other factors, hamper myocardial function. We investigated the effects of MV with injuriously high tidal volumes on the myocardium in an animal model of sepsis. Methods Normal rats and intraperitoneal (i.p.) lipopolysaccharide (LPS)-treated rats were ventilated with low (6 ml/kg) and high (19 ml/kg) tidal volumes (Vt) under general anesthesia. Non-ventilated animals served as controls. Mean arterial pressure (MAP), central venous pressure (CVP), cardiac output (CO) and pulmonary plateau pressure (Pplat) were measured. Ex vivo myocardial function was measured in isolated Langendorff-perfused hearts. Cardiac expression of endothelial vascular cell adhesion molecule (VCAM)-1 and edema were measured to evaluate endothelial inflammation and leakage. Results MAP decreased after LPS-treatment and Vt-dependently, both independent of each other and with interaction. MV Vt-dependently increased CVP and Pplat and decreased CO. LPS-induced peritonitis decreased myocardial function ex vivo but MV attenuated systolic dysfunction Vt-dependently. Cardiac endothelial VCAM-1 expression was increased by LPS treatment independent of MV. Cardiac edema was lowered Vt-dependently by MV, particularly after LPS, and correlated inversely with systolic myocardial function parameters ex vivo. Conclusion MV attenuated LPS-induced systolic myocardial dysfunction in a Vt-dependent manner. This was associated with a reduction in cardiac edema following a lower transmural coronary venous outflow pressure during LPS-induced coronary inflammation.

2012-01-01

127

Terminalia chebula extract protects OGD-R induced PC12 cell death and inhibits lps induced microglia activation.  

PubMed

Terminalia chebula, native to Southeast Asia, is a popular medicinal plant in Ayurveda. It has been previously reported to have strong antioxidant and anti-inflammatory efficacy. In this study, we aimed to investigate if fruit extract from T. chebula might protect neuronal cells against ischemia and related diseases by reduction of oxidative damage and inflammation in rat pheochromocytoma cells (PC12) using in vitro oxygen-glucose deprivation followed by reoxygenation (OGD-R) ischemia and hydrogen peroxide (H2O2) induced cell death. Cell survival was evaluated by a 2-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Free radical scavenging, lipid peroxidation and nitric oxide inhibition were measured by diphenyl-1-picrylhydrazyl (DPPH), thiobarbituric acid (TBA) and Griess reagent, respectively. We found that T. chebula extract: (1) increases the survival of cells subjected to OGD-R by 68%, and H2O2 by 91.4%; (2) scavenges the DPPH free radical by 96% and decreases malondialdehyde (MDA) levels from 237.0 ± 15.2% to 93.7 ± 2.2%; (3) reduces NO production and death rate of microglia cells stimulated by lipopolysaccharide (LPS). These results suggest that T. chebula extract has the potential as a natural herbal medicine, to protect the cells from ischemic damage and the possible mechanism might be the inhibition of oxidative and inflammatory processes. PMID:23519197

Gaire, Bhakta Prasad; Jamarkattel-Pandit, Nirmala; Lee, Donghun; Song, Jungbin; Kim, Ji Young; Park, Juyeon; Jung, Soyoung; Choi, Ho-Young; Kim, Hocheol

2013-03-19

128

Effects of aldosterone and related steroids on LPS-induced increased expression of inducible NOS in rat aortic smooth muscle cells  

PubMed Central

BACKGROUND AND PURPOSE Expression of inducible NOS (iNOS) is important in certain inflammatory diseases. We determined if the hormone aldosterone, a mineralocorticoid receptor (MR) agonist, affects LPS activation of iNOS expression in rat aortic smooth muscle cells (RASMC). EXPERIMENTAL APPROACH Cultured RASMC were treated with LPS, with or without agonists/antagonists of steroid receptors. iNOS expression was determined by nitrite assays on culture medium removed from treated cells and by immunoblotting of cell protein extracts. KEY RESULTS LPS (1 µg·mL?1) increased nitrite and iNOS protein above that in control (untreated) cells. These effects of LPS were reduced by aldosterone (0.1–10 µM). The MR antagonists, eplerenone (10 µM) and spironolactone (10 or 50 µM), did not inhibit these actions of 1 µM aldosterone, but the latter were prevented by 10 µM mifepristone, a glucocorticoid (GR) and progestogen receptor (PR) antagonist. Mifepristone also prevented the reduction of LPS-induced nitrite increase produced by 1 µM dexamethasone (GR agonist) and 10 µM progesterone (PR agonist). Spironolactone (10–50 µM) by itself decreased LPS-induced increases in nitrite and iNOS protein. Mifepristone (10 µM) partially reversed these effects of 10 µM spironolactone, but not those of 50 µM; the effects of 50 µM spironolactone were also unchanged when mifepristone was increased to 50 µM. CONCLUSIONS AND IMPLICATIONS This pharmacological profile suggests that aldosterone, and possibly 10 µM spironolactone, use mechanisms that are dependent on PR and/or GR, but not MR, to inhibit iNOS induction in RASMC. With 50 µM spironolactone, other inhibitory mechanisms requiring further investigation may become predominant.

Godfrey, V; Martin, AL; Struthers, AD; Lyles, GA

2011-01-01

129

A critical role for suppressors of cytokine signaling 3 in regulating LPS-induced transcriptional activation of matrix metalloproteinase-13 in osteoblasts  

PubMed Central

Suppressor of cytokine signaling 3 (SOCS3) is a key regulator of cytokine signaling in macrophages and T cells. Although SOCS3 seems to contribute to the balance between the pro-inflammatory actions of IL-6 family of cytokines and anti-inflammatory signaling of IL-10 by negatively regulating gp130/Jak/Stat3 signal transduction, how and the molecular mechanisms whereby SOCS3 controls the downstream impact of TLR4 are largely unknown and current data are controversial. Furthermore, very little is known regarding SOCS3 function in cells other than myeloid cells and T cells. Our previous study demonstrates that SOCS3 is expressed in osteoblasts and functions as a critical inhibitor of LPS-induced IL-6 expression. However, the function of SOCS3 in osteoblasts remains largely unknown. In the current study, we report for the first time that LPS stimulation of osteoblasts induces the transcriptional activation of matrix metalloproteinase (MMP)-13, a central regulator of bone resorption. Importantly, we demonstrate that SOCS3 overexpression leads to a significant decrease of LPS-induced MMP-13 expression in both primary murine calvariae osteoblasts and a mouse osteoblast-like cell line, MC3T3-E1. Our findings implicate SOCS3 as an important regulatory mediator in bone inflammatory diseases by targeting MMP-13.

Gao, Anqi; Kantarci, Alpdogan; Herrera, Bruno Schneider; Gao, Hongwei

2013-01-01

130

Macrophage specific delivery of TNF-? siRNA complexed with ?-1,3-glucan inhibits LPS-induced cytokine production in a murine acute hepatitis model.  

PubMed

RNA interference therapy utilizes physiological gene silencing that is originally found as a defense function against foreign RNAs. To silence the target gene, short double stranded RNA has to be delivered to cytosol. However, lack of a suitable delivering carrier is the major obstacle to practical usage. In this study, we present a novel complex consisting of ?-1,3-glucan and short interference RNA (siRNA) as a solution for the problem. We used a ?-1,3-glucan schizophyllan (SPG) and a siRNA (dA-siTNF?) that is designed to suppress tumor necrosis factor alpha (TNF-?), where the sense strand of siRNA has (dA(40)) tail to induce complexation with SPG. The dA-siTNF?/SPG complex showed higher affinity to recombinant dectin-1 than SPG itself, where dectin-1 is a ?-1,3-glucan receptor expressed on antigen presenting cells and can be a target for specific delivery. The complex suppressed lipopolysaccharide (LPS)-induced TNF-? secretion by peritoneal macrophages in vitro. When the complex was intravenously injected, the oligonucleotide accumulated in liver; especially distributed into Kupffer cells. The complex significantly decreased the serum TNF-? level for the mouse model of LPS-induced acute hepatitis. This new siRNA delivery system may overcome the problem for RNA interference therapy because of its non-toxicity and high target specificity. PMID:23523387

Mochizuki, Shinichi; Morishita, Hiromi; Sakurai, Kazuo

2013-03-05

131

MD-2 interacts with Lyn kinase and is tyrosine phosphorylated following LPS-induced activation of the Toll-like receptor 4 signaling pathway  

PubMed Central

Stimulation with LPS induces tyrosine phosphorylation of numerous proteins involved in the TLR signaling pathway. In this study, we demonstrate that MD-2 is also tyrosine phosphorylated following LPS stimulation. LPS-induced tyrosine phosphorylation of MD-2 is specific, it is blocked by the tyrosine kinase inhibitor, Herbimycin A, and by an inhibitor of endocytosis, Cytochalsin-D, suggesting that MD-2 phosphorylation occurs during trafficking of MD2 and not on cell surface. Furthermore, we identify two possible phospho-accepting tyrosine residues at positions 22 and 131. Mutant proteins in which these tyrosines were changed to phenylalanine have reduced phosphorylation and significantly diminished ability to activate NF-?B in response to LPS. In addition, MD2 co-precipitates and colocalizes with Lyn kinase, most likely in ER. A Lyn-binding peptide inhibitor abolished MD2 tyrosine phosphorylation, suggesting that Lyn is a likely candidate to be the kinase required for MD-2 tyrosine phophorylation. Our study demonstrates that tyrosine phosphorylation of MD-2 is important for signaling following exposure to LPS and underscores the importance of this event in mediating an efficient and prompt immune response.

Gray, Pearl; Dagvadorj, Jargalsaikhan; Michelsen, Kathrin S.; Brikos, Constantinos; Rentsendorj, Altan; Town, Terrence; Crother, Timothy R.; Arditi, Moshe

2011-01-01

132

Alterations in TH- and ChAT-immunoreactive neurons in the DMV and gastric dysmotility in an LPS-induced PD rat model.  

PubMed

To study movement disorder in Parkinson's disease (PD), an animal model of PD can be created by injecting lipopolysaccharide (LPS) into the substantia nigra of rats. In addition to body movement disorders, patients with PD often experience gastrointestinal (GI) dysfunction, such as gastroparesis. However, the underlying mechanism of these disorders remains unclear. The dorsal motor nucleus of vagus (DMV) is a well-known visceral nucleus that regulates GI function. The present study investigated alterations in DMV neurons and gastric motility in rats with LPS-induced PD (LPS-PD rats). Gastric motility was recorded using a strain gauge force transducer in vivo. The distributions of tyrosine hydroxylase (TH)- and choline acetyltransferase (ChAT)-positive neurons in the DMV were determined using immunofluorescence and confocal laser microscopy. Our results indicated that in LPS-PD rats, the number of neurons in the substantia nigra, including neurons with TH immunoreactivity, was markedly reduced, although glial cell proliferation was clearly observed. However, enhanced TH immunoreactivity and decreased ChAT immunoreactivity were found in the DMV. Furthermore, weakened gastric motility was recorded in anesthetized LPS-PD rats. In conclusion, rats with LPS-induced PD exhibited gastric dysmotility with an alteration in DMV neurons. This PD model may be used to study autonomic nervous system disorders that are often observed in patients with early-stage PD. PMID:23701914

Zheng, Li-Fei; Zhang, Yue; Chen, Chang-Liang; Song, Jin; Fan, Rui-Fang; Cai, Qing-Qing; Wang, Zhi-Yong; Zhu, Jin-Xia

2013-05-20

133

Inorganic Polyphosphate Suppresses Lipopolysaccharide-Induced Inducible Nitric Oxide Synthase (iNOS) Expression in Macrophages  

PubMed Central

In response to infection, macrophages produce a series of inflammatory mediators, including nitric oxide (NO), to eliminate pathogens. The production of these molecules is tightly regulated via various mechanisms, as excessive responses are often detrimental to host tissues. Here, we report that inorganic polyphosphate [poly(P)], a linear polymer of orthophosphate ubiquitously found in mammalian cells, suppresses inducible nitric oxide synthase (iNOS) expression induced by lipopolysaccharide (LPS), a cell wall component of Gram-negative bacteria, in mouse peritoneal macrophages. Poly(P) with longer chains is more potent than those with shorter chains in suppressing LPS-induced iNOS expression. In addition, poly(P) decreased LPS-induced NO release. Moreover, poly(P) suppressed iNOS mRNA expression induced by LPS stimulation, thereby indicating that poly(P) reduces LPS-induced iNOS expression by down-regulation at the mRNA level. In contrast, poly(P) did not affect the LPS-induced release of TNF, another inflammatory mediator. Poly(P) may serve as a regulatory factor of innate immunity by modulating iNOS expression in macrophages.

Harada, Kana; Shiba, Toshikazu; Doi, Kazuya; Morita, Koji; Kubo, Takayasu; Makihara, Yusuke; Piattelli, Adriano; Akagawa, Yasumasa

2013-01-01

134

Anti-inflammatory and anticoagulative effects of paeonol on LPS-induced acute lung injury in rats.  

PubMed

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

2012-02-21

135

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.

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

2012-01-01

136

Theaflavin Inhibits LPS-Induced IL-6, MCP-1, and ICAM-1 Expression in Bone Marrow-Derived Macrophages Through the Blockade of NF-?B and MAPK Signaling Pathways  

PubMed Central

Theaflavin, the main polyphenol in black tea, has anti-inflammatory, antioxidative, anti-mutagenic, and anti-carcinogenic properties. The aim of this study was to evaluate the effects of theaflavin on lipopolysaccharide (LPS)-induced innate signaling and expression of pro-inflammatory mediators in bone marrow-derived macrophages isolated from ICR mice. The effects of theaflavin on the expression of proinflammatory mediators, LPS-induced nuclear factor-kappa B (NF-?B), and mitogen-activated protein kinase (MAPK) signaling pathways were examined by reverse transcriptase-polymerase chain reaction (RT-PCR), Western blotting, and immunofluorescence. LPS-induced interleukin-6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), and intercellular adhesion molecule-1 (ICAM-1) expression was inhibited by theaflavin. LPS-induced inhibitor kappa B alpha (I?B?) degradation and nuclear translocation of RelA were blocked by theaflavin. LPS-induced phosphorylation of extracellular signal-regulated kinase1/2 (ERK1/2), c-Jun-N-terminal kinase (JNK), and p38 MAPK was inhibited by theaflavin. The inhibitory effect of theaflavin on IL-6, MCP-1, and ICAM-1 expression was completely inhibited by Bay11-7082 (NF-?B inhibitor). The inhibitory effect of theaflavin on IL-6 and ICAM-1 expression was inhibited by SB203580 (p38 MAPK inhibitor). The inhibitory effect of theaflavin on MCP-1 expression was inhibited by SP600125 (JNK inhibitor). These results indicate that theaflavin prevents LPS-induced IL-6, MCP-1, and ICAM-1 expression through blockade of NF-?B and MAPK signaling pathways in bone marrow-derived macrophages.

Kim, Seewan

2011-01-01

137

Theaflavin Inhibits LPS-Induced IL-6, MCP-1, and ICAM-1 Expression in Bone Marrow-Derived Macrophages Through the Blockade of NF-?B and MAPK Signaling Pathways.  

PubMed

Theaflavin, the main polyphenol in black tea, has anti-inflammatory, antioxidative, anti-mutagenic, and anti-carcinogenic properties. The aim of this study was to evaluate the effects of theaflavin on lipopolysaccharide (LPS)-induced innate signaling and expression of pro-inflammatory mediators in bone marrow-derived macrophages isolated from ICR mice. The effects of theaflavin on the expression of proinflammatory mediators, LPS-induced nuclear factor-kappa B (NF-?B), and mitogen-activated protein kinase (MAPK) signaling pathways were examined by reverse transcriptase-polymerase chain reaction (RT-PCR), Western blotting, and immunofluorescence. LPS-induced interleukin-6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), and intercellular adhesion molecule-1 (ICAM-1) expression was inhibited by theaflavin. LPS-induced inhibitor kappa B alpha (I?B?) degradation and nuclear translocation of RelA were blocked by theaflavin. LPS-induced phosphorylation of extracellular signal-regulated kinase1/2 (ERK1/2), c-Jun-N-terminal kinase (JNK), and p38 MAPK was inhibited by theaflavin. The inhibitory effect of theaflavin on IL-6, MCP-1, and ICAM-1 expression was completely inhibited by Bay11-7082 (NF-?B inhibitor). The inhibitory effect of theaflavin on IL-6 and ICAM-1 expression was inhibited by SB203580 (p38 MAPK inhibitor). The inhibitory effect of theaflavin on MCP-1 expression was inhibited by SP600125 (JNK inhibitor). These results indicate that theaflavin prevents LPS-induced IL-6, MCP-1, and ICAM-1 expression through blockade of NF-?B and MAPK signaling pathways in bone marrow-derived macrophages. PMID:22111069

Kim, Seewan; Joo, Young-Eun

2011-08-31

138

Calcineurin inactivation leads to decreased responsiveness to LPS in macrophages and dendritic cells and protects against LPS-induced toxicity in vivo.  

PubMed

Microbial components such as lipopolysaccharide (LPS) bind to Toll-like receptors (TLRs) and activate innate and inflammatory responses. Responses to LPS and other microbial components are limited by the activation of negative feedback mechanisms that reduce responsiveness to subsequent LPS exposure, often termed LPS tolerance. Our laboratory has previously shown that calcineurin, a phosphatase known for its activation of T cells via NFAT, negatively regulates the TLR pathway in macrophages; consequently, calcineurin inhibitors (FK506 and cyclosporin A) mimic TLR ligands in activating the TLR pathway, NF-KB, and associated innate and inflammatory responses. This study investigated the physiological consequences of calcineurin inactivation for LPS-induced inflammatory responses in vitro and in vivo using two models: calcineurin inhibition by FK506 (tacrolimus) and myeloid cell-specific calcineurin deletion. Activation of dendritic cells and macrophages with FK506 in vitro was shown to induce a state of reduced responsiveness to LPS (i.e. a form of LPS tolerance). Similarly, macrophages from FK506-treated mice or from mice in which the calcineurin B1 (CnB1) subunit was conditionally knocked out in myeloid cells were found to have diminished LPS-induced inflammatory responses. In addition, mice with CnB1-deficient myeloid cells and mice undergoing FK506 treatment showed improved survival and recovery when challenged with high doses of systemic LPS compared to controls. These results demonstrate that inactivation of calcineurin in macrophages and other myeloid cells by inhibition or deletion can induce a form of LPS tolerance and protect the host from LPS toxicity in vivo. PMID:19318421

Jennings, Charay; Kusler, Brenda; Jones, Patricia P

2009-04-01

139

Spin Trapping Agent, Phenyl N- tertbutyl Nitrone (PBN) Inhibits Induction of Nitric Oxide Synthase in Endotoxin-Induced Shock in Mice  

Microsoft Academic Search

Spin trapping agent, phenyl N-tert-butyl nitrone (PBN) significantly reduces mortality due to lipopolysaccharide (LPS)-induced shock in Balb\\/c mice as had previously been shown in rats. We hypothesized that PBN decreases mortality by directly or indirectly inhibiting nitric oxide (NO) generation. Therefore, we determined the effect of PBN administration on LPS-induced NO generation in mice. NO generation was monitored in the

T. Miyajima; Y. Kotake

1995-01-01

140

The influence of ETA and ETB receptor blockers on LPS-induced oxidative stress and NF-?B signaling pathway in heart.  

PubMed

The aim of this study was to assess whether an endothelin-A receptor (ETA-R) blocker, BQ123, or an endothelin-B (ETB-R) receptor blocker, BQ788, influences nuclear factor kappa beta (NF-?B) pathway, free radical generation, tumor necrosis factor-alpha (TNF-?) concentration, and glutathione redox system in hearts obtained from lipopolysaccharide (LPS)-induced endotoxic rats. The study was performed on rats divided into groups: 1) saline, 2) saline + LPS (15 mg/kg), 3) BQ123 (1 mg/kg b.w.) + LPS, 4) BQ123 (0.5 mg/kg b.w.) + LPS, 5) BQ788 (3 mg/kg b.w.) + LPS. The ETA-R and ETB-R antagonists were injected i.v. 30 min before LPS administration. In rats, BQ123 caused a significant decrease in TBARS (p < 0.05) but not in H2O2 concentration. It also decreased tissue protein level and improved tissue redox status (p < 0.01). Only a dose of 1 mg/kg decreased TNF-? concentration (p < 0.05). BQ788 lowered TBARS, H2O2 and protein concentration (p < 0.05; p < 0.02; p < 0.001, respectively), however, it did not affect TNF-? concentration. Neither ETA-R nor ETB-R blockers influenced LPS-induced increase in p65 subunit level and activation of NF-?B pathway. Our results demonstrated that ETA-R blockage is more effective in inhibiting free radical generation and improving heart antioxidant properties than ETB-R blockage under oxidative stress. NF-?B pathway is not incorporated in ETA-R and ETB-R influence on ROS production. PMID:23047940

Piechota-Polanczyk, Aleksandra; Kleniewska, Paulina; Gor?ca, Anna

2012-09-01

141

Caspase-1 processes IFN-gamma-inducing factor and regulates LPS-induced IFN-gamma production.  

PubMed

Interferon-gamma-inducing factor (IGIF, interleukin-18) is a recently described cytokine that shares structural features with the interleukin-1 (IL-1) family of proteins and functional properties with IL-12. Like IL-12, IGIF is a potent inducer of interferon (IFN)-gamma from T cells and natural killer cells. IGIF is synthesized as a biologically inactive precursor molecule (proIGIF). The cellular production of IL-1beta, a cytokine implicated in a variety of inflammatory diseases, requires cleavage of its precursor (proIL-1beta) at an Asp-X site by interleukin-1beta-converting enzyme (ICE, recently termed caspase-1). The Asp-X sequence at the putative processing site in proIGIF suggests that a protease such as caspase-1 might be involved in the maturation of IGIF. Here we demonstrate that caspase-1 processes proIGIF and proIL-1beta with equivalent efficiencies in vitro. A selective caspase-1 inhibitor blocks both lipopolysaccharide-induced IL-1beta and IFN-gamma production from human mononuclear cells. Furthermore, caspase-1-deficient mice are defective in lipopolysaccharide-induced IFN-gamma production. Our results thus implicate caspase-1 in the physiological production of IGIF and demonstrate that it plays a critical role in the regulation of multiple proinflammatory cytokines. Specific caspase-1 inhibitors would provide a new class of anti-inflammatory drugs with multipotent action. PMID:9121587

Ghayur, T; Banerjee, S; Hugunin, M; Butler, D; Herzog, L; Carter, A; Quintal, L; Sekut, L; Talanian, R; Paskind, M; Wong, W; Kamen, R; Tracey, D; Allen, H

1997-04-10

142

Inhibitory effect of citrinin on lipopolisaccharide-induced nitric oxide production by mouse macrophage cells.  

PubMed

The present study evaluated the immunotoxicity of citrinin (CIT), a mycotoxin produced by several Aspergillus, Penicillium, and Monascus species. Because nitric oxide (NO), a pro-inflammatory mediator, plays an important role in the protection from pathogens, we addressed the effect of CIT on NO production by a mouse macrophage-like cell line RAW264 activated with lipopolysaccharide (LPS). LPS-induced NO release from RAW264 cells was inhibited by CIT. Moreover, the transcription and expression of inducible NO synthase (iNOS) by LPS was suppressed by CIT. These results show that CIT suppressed the LPS-induced NO production and iNOS expression, which contribute to the host protection against invading pathogens. This suggests that CIT on LPS-induced NO release may exert adverse effects in macrophages, indicating immunotoxic effects of this toxin. . PMID:23897301

Sugiyama, Kei-Ichi; Yamazaki, Rino; Kinoshita, Mawo; Kamata, Yoichi; Tani, Fumito; Minai, Yuji; Sugita-Konishi, Yoshiko

2013-07-30

143

Modulating effects of prenatal stress on hyperthermia induced in adult rat offspring by restraint or LPS-induced stress  

Microsoft Academic Search

The present study was carried out to investigate the effects of prenatal stress on stress-induced hyperthermia in adult rats. Prenatal stress was administered daily for 3 days (embryonic days 15–17) by restraining pregnant rats in a small cage either for 30 or 240 min. After birth, foster mothers raised the pups. Offspring were tested at 9–10-weeks-old. Changes in body temperature

Makoto Hashimoto; Tatsuo Watanabe; Takashi Fujioka; Nobusuke Tan; Hiroshi Yamashita; Shoji Nakamura

2001-01-01

144

Posttranscriptional inhibition of lipopolysaccharide-induced expression of inducible nitric oxide synthase by Gö6976 in murine microglia  

Microsoft Academic Search

Glia in the brain respond to various toxins with an increased expression of inducible nitric oxide synthase (iNOS) and an increased production of nitric oxide (NO). Here, we report that lipopolysaccharide (LPS)-induced expression of iNOS was down-regulated post-transcriptionally through the destabilization of iNOS mRNA by the indolocarbazole compound, Gö6976, in murine microglia. This Gö6976 effect is specific for iNOS since

G.-H. Jeohn; R. C. C. Chang; W.-G. Kim; B. Wilson; R. P. Mohney; W. C. Wetsel; J.-S. Hong

2000-01-01

145

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

146

Low dose of carbon monoxide intraperitoneal injection provides potent protection against GalN/LPS-induced acute liver injury in mice.  

PubMed

Carbon monoxide (CO) is an important effector-signaling molecule involved in various pathophysiological processes. Here we investigated the protective effects of exogenous CO in a murine model of acute liver damage induced by d-galactosamine (GalN) and lipopolysaccharide (LPS). Exogenous CO gas was administered to mice via intraperitoneal injection (first at a dose of 15?ml?kg(-1) and then, 6?h later, 8?ml?kg(-1) ), which caused a significant elevation of blood carboxyhemoglobin levels of up to 12-14% for more than 12?h. GalN/LPS were given to induce acute liver damage in mice 30?min prior to CO exposure. This showed that GalN/LPS induced severe liver injury in mice, whereas CO injection remarkably improved the survival rate of mice and led to attenuated hepatocellular damage. CO exhibited anti-oxidative capabilities by inhibiting hepatic malondialdehyde contents and restoring superoxide dismutase and glutathione, as well as by reducing inducible NOS/NO production. The anti-apoptotic and anti-inflammatory effects of CO were substantial, characterized by a notable inhibition of hepatocyte apoptosis and a reduction of pro-inflammatory cytokines in mice. Our findings thus supported the hypothesis that exogenous CO provides protective effects against acute liver damage in mice, mainly dependent on its anti-oxidative, anti-inflammatory and anti-apoptotic properties. Copyright © 2012 John Wiley & Sons, Ltd. PMID:23015538

Wen, Zongmei; Liu, Yan; Li, Feng; Wen, Tao

2012-09-27

147

SOCS3 Expression Correlates with Severity of Inflammation, Expression of Proinflammatory Cytokines, and Activation of STAT3 and p38 MAPK in LPS-Induced Inflammation In Vivo  

PubMed Central

SOCS3 is an inducible endogenous negative regulator of JAK/STAT pathway, which is relevant in inflammatory conditions. We used a model of LPS-induced periodontal disease in rats to correlate SOCS3 expression with the inflammatory status. In vitro we used a murine macrophage cell line to assess the physical interaction between SOCS3 and STAT3 by coimmunoprecipitation. 30?ug of LPS from Escherichia coli were injected in the gingival tissues on the palatal aspect of first molars of the animals 3x/week for up to 4 weeks. Control animals were injected with the vehicle (PBS). The rats were sacrificed at 7, 15, and 30 days. Inflammation and gene expression were assessed by stereometric analysis, immunohistochemistry, RT-qPCR, and western blot. LPS injections increased inflammation, paralleled by an upregulation of SOCS3, of the proinflammatory cytokines IL-1?, IL-6, and TNF-? and increased phosphorylation of STAT3 and p38 MAPK. SOCS3 expression accompanied the severity of inflammation and the expression of proinflammatory cytokines, as well as the activation status of STAT3 and p38 MAPK. LPS stimulation in a macrophage cell line in vitro induced transient STAT3 activation, which was inversely correlated with a dynamic physical interaction with SOCS3, suggesting that this may be a mechanism for SOCS3 regulatory function.

Chaves de Souza, Joao Antonio; Nogueira, Andressa Vilas Boas; Chaves de Souza, Pedro Paulo; Kim, Yeon Jung; Silva Lobo, Caroline; Pimentel Lopes de Oliveira, Guilherme Jose; Cirelli, Joni Augusto; Garlet, Gustavo Pompermaier; Rossa, Carlos

2013-01-01

148

FLN29, a novel interferon- and LPS-inducible gene acting as a negative regulator of toll-like receptor signaling.  

PubMed

Lipopolysaccharide (LPS) activates macrophages through toll-like receptor (TLR) 4. Although the mechanism of the TLR signaling pathway has been well documented, the mechanism of the negative regulation in response to LPS, particularly LPS tolerance, is still poorly understood. In this study we identified and characterized a novel interferon- and LPS-inducible gene, FLN29, which contains a TRAF6-related zinc finger motif and TRAF family member-associated NF-kappaB activator-related sequences. The induction of FLN29 was dependent on STAT1. The forced expression of FLN29 in macrophage-like RAW cells resulted in the suppression of TLR-mediated NF-kappaB and mitogen-activated protein kinase activation, while a reduced expression of FLN29 by small interfering RNA partly cancelled the down-regulation of LPS signaling. Furthermore, we demonstrated that NF-kappaB activation induced by TRAF6 and TAB2 was impaired by co-expression of FLN29, suggesting FLN29 may regulate the downstream of TRAF6. Taken together, FLN29 is a new negative feedback regulator of TLR signaling. PMID:16221674

Mashima, Ryuichi; Saeki, Kazuko; Aki, Daisuke; Minoda, Yasumasa; Takaki, Hiromi; Sanada, Takahito; Kobayashi, Takashi; Aburatani, Hiroyuki; Yamanashi, Yuji; Yoshimura, Akihiko

2005-10-12

149

Inhibition of sPLA2-IIA Prevents LPS-Induced Neuroinflammation by Suppressing ERK1/2-cPLA2? Pathway in Mice Cerebral Cortex  

PubMed Central

Neuroinflammation is involved in various central nervous system (CNS) disorders, including brain infections, ischemia, trauma, stroke, and degenerative CNS diseases. In the CNS inflammation, secretory phospholipase A2-IIA (sPLA2-IIA) acts as a mediator, resulting in the generation of the precursors of pro-inflammatory lipid mediators, such as prostaglandins (PGs) and leukotrienes (LTs). However, the role of sPLA2-IIA in neuroinflammation is more complicated and remains unclear yet. In the present study, we investigated the effect of sPLA2-IIA inhibition by specific inhibitor SC-215 on the inflammation in LPS-induced mice cerebral cortex and primary astrocytes. Our results showed that the inhibition of sPLA2-IIA alleviated the release of PGE2 by suppressing the activation of ERK1/2, cPLA2?, COX-2 and mPGES-1. These findings demonstrated that sPLA2-IIA showed the potential to regulate the neuroinflammation in vivo and in vitro, indicating that sPLA2-IIA might be a novel target for the treatment of acute neuroinflammation.

Xiang, Yanxiao; Chen, Lin; Liu, Huiqing; Liu, Xiaoqian; Wei, Xinbing; Sun, Baozhu; Wang, Tian; Zhang, Xiumei

2013-01-01

150

Identification of a novel human MD-2 splice variant that negatively regulates LPS-induced Toll-like receptor 4 signaling  

PubMed Central

Myeloid differentiation factor 2 (MD-2) is a secreted glycoprotein that assembles with Toll-like receptor 4 (TLR4) to form a functional signaling receptor for bacterial lipopolysaccharide (LPS). In this study we have identified a novel alternatively spliced isoform of human MD-2, termed MD-2 short (MD-2s), which lacks the region encoded by exon 2 of the MD-2 gene. Similar to MD-2, MD-2s is glycosylated and secreted. MD-2s also interacted with LPS and TLR4, but failed to mediate LPS-induced NF-?B activation and interleukin-8 production. We show that MD-2s is upregulated upon IFN-?, IL-6 and TLR stimulation and negatively regulates LPS-mediated TLR4 signaling. Furthermore, MD-2s competitively inhibited binding of MD-2 to TLR4. Our study therefore pinpoints a mechanism that may be employed to regulate TLR4 activation at the onset of signaling and identifies MD-2s as a potential therapeutic candidate to treat human diseases characterized by an overly exuberant or chronic immune response to LPS.

Gray, Pearl; Michelsen, Kathrin S.; Sirois, Cherilyn M.; Lowe, Emily; Shimada, Kenichi; Crother, Timothy R.; Chen, Shuang; Brikos, Constantinos; Bulut, Yonca; Latz, Eicke; Underhill, David; Arditi, Moshe

2011-01-01

151

Critical Roles of the WASP N-Terminal Domain and Btk in LPS-Induced Inflammatory Response in Macrophages  

PubMed Central

While Wiskott-Aldrich syndrome protein (WASP) plays critical roles in TCR signaling as an adaptor molecule, how it transduces innate immune signals remains to be elucidated. To investigate the roles of WASP in innate immune cells, we established bone marrow-derived macrophage (BMDM) cell lines from WASP15 transgenic (Tg) mice overexpressing the WASP N-terminal region (exons 1–5). Upon LPS stimulation, WASP15 Tg BMDM cell lines produce lower levels of inflammatory cytokines, such as TNF-?, IL-6, and IL-12p40 than the wild-type BMDM cell line. In addition, the production of nitric oxide by WASP15 Tg BMDM cells in response to LPS and IFN-? was significantly impaired. Furthermore, we uncovered that the WASP N-terminal domain associates with the Src homology (SH) 3 domain of Bruton's tyrosine kinase (Btk). Overexpression of the WASP N-terminal domain diminishes the extent of tyrosine phosphorylation of endogenous WASP in WASP15 Tg BMDM cells, possibly by interfering with the specific binding between endogenous WASP and Btk during LPS signaling. These observations strongly suggest that the interaction between WASP N-terminal domain and Btk plays important roles in the LPS signaling cascade in innate immunity.

Sakuma, Chisato; Sato, Mitsuru; Takenouchi, Takato; Chiba, Joe; Kitani, Hiroshi

2012-01-01

152

Inhibition of Glycogen Synthase Kinase 3? Ameliorates D-GalN/LPS-Induced Liver Injury by Reducing Endoplasmic Reticulum Stress-Triggered Apoptosis  

PubMed Central

Background Glycogen synthase kinase 3?(GSK3?) is a ubiquitous serine-threonine protein kinase that participates in numerous cellular processes and disease pathophysiology. We aimed to determine therapeutic potential of GSK3? inhibition and its mechanism in a well-characterized model of lipopolysaccharide (LPS)-induced model of acute liver failure (ALF). Methodology In a murine ALF model induced by D-GalN(700 mg/kg)/LPS(10 µg/kg), we analyzed GSK3? mechanisms using a specific chemical inhibitor, SB216763, and detected the role of endoplasmic reticulum stress (ERS). Mice were administered SB216763 at 2 h before or after D-GalN/LPS injection, respectively, and then sacrificed 6 h after D-GalN/LPS treatment to evaluate its prophylactic and therapeutic function. The lethality rate, liver damage, ERS, cytokine expression, MAP kinase, hepatocyte apoptosis and expression of TLR 4 were evaluated, respectively. Whether the inhibition of GSK3? activation protected hepatocyte from ERS-induced apoptosis was investigated in vitro. Principal Findings GSK3? became quickly activated (dephosphorylated) upon D-GalN/LPS exposure. Administration of SB216763 not only ameliorated liver injury, as evidenced by reduced transaminase levels, and well-preserved liver architecture, but also decreased lethality. Moreover, GSK3? inhibition resulted in down-regulation of pro-apoptotic proteins C/EBP–homologous protein(CHOP) and caspase-12, which are related to ERS. To further demonstrate the role of ERS, we found that GSK3? inhibition protected hepatocyte from ERS-induced cell death. GSK3? inhibition down-regulated the MAPK pathways, reduced expression of inflammatory cytokines and decreased expression of TLR4. Conclusions Our findings demonstrate the key function of GSK3? signaling in the pathophysiology of ALF, especially in regulating the ERS, and provide a rationale for targeting GSK3? as a potential therapeutic strategy to ameliorate ALF.

Zhang, Haiyan; Wen, Tao; Piao, Zhengfu; Zhou, Li; Zheng, Sujun; Zhang, Jing; Chen, Yu; Han, Yuanping; Duan, Zhongping; Ma, Yingji

2012-01-01

153

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...

154

E1A Has No Effect on LPS-Induced IL6 Secretion in Rat Alveolar Epithelial Cells  

Microsoft Academic Search

Background: The adenoviral protein E1A has been suggested to play a role in the pathophysiological development of chronic obstructive pulmonary disease (COPD) by inducing expression of inflammatory factors. It is well known that glucocorticoids are important inhibitors of inflammation. In the treatment of COPD corticosteroid therapy commonly has little or no anti-inflammatory effect. We hypothesized that the anti-inflammatory effect of

Juan Chen; Jiandong Luo; Bing Li; Pixin Ran

2009-01-01

155

The Nitrated Fatty Acid 10-Nitro-oleate Diminishes Severity of LPS-Induced Acute Lung Injury in Mice  

PubMed Central

Acute lung injury (ALI) is an inflammatory condition culminating in respiratory failure. There is currently no effective pharmacological treatment. Nitrated fatty acids (NFAs) have been shown to exert anti-inflammatory effects. We therefore hypothesized that delivery of NFAs directly to the site of inflammation would reduce the severity of ALI. Pulmonary delivery of 10-nitro-oleate following endotoxin-induced ALI in mice reduced markers of lung inflammation and injury, including capillary leakage, lung edema, infiltration of neutrophils into the lung, and oxidant stress, as well as plasma levels of proinflammatory cytokines. Nitro-oleate delivery likewise downregulated expression of proinflammatory genes by alveolar macrophages, key cells in regulation of lung inflammation. These effects may be accounted for by the observed increases in the activity of PPAR-? and the PPAR-?-induced antioxidant transcription factor Nrf2, together with the decreased activity of NF-?B. Our results demonstrate that pulmonary delivery of NFAs reduces severity of acute lung injury and suggest potential utility of these molecules in other inflammatory lung diseases.

Reddy, Aravind T.; Lakshmi, Sowmya P.; Reddy, Raju C.

2012-01-01

156

High-affinity LPS binding domain(s) in recombinant factor C of a horseshoe crab neutralizes LPS-induced lethality.  

PubMed

SSCrFCES is a biologically active, recombinant fragment of factor C, which is the endotoxin-sensitive serine protease of the LAL coagulation cascade. The approximately 38 kDa protein represents the LPS binding domain of factor C. A novel secretory signal directs the secretion of SSCrFCES into the culture supernatant of Drosophila cells, and hence it is readily purified. By differential ultrafiltration followed by preparative isoelectric membrane electrophoresis, SSCrFCES was purified as an isoelectrically homogeneous and stable monomeric protein. The ability of SSCrFCES to bind lipid A was analyzed using an ELISA-based assay as well as surface plasmon resonance. SSCrFCES exhibits high positive cooperativity of binding to two or three lipid A molecules, with a Hill's coefficient of 2.2. The 50% endotoxin-neutralizing concentration of SSCrFCES against 200 EU of endotoxin is approximately 0.069 microM, suggesting that SSCrFCES is an effective inhibitor of LAL coagulation cascade. Although partially attenuated by human serum, as little as 1 microM of SSCrFCES inhibits the LPS-induced secretion of hTNF-alpha and hIL-8 by THP-1 and human peripheral blood mononuclear cells with greater potency than polymyxin B. SSCrFCES is noncytotoxic, with a clearance rate of 4.7 ml/min. The L.D.(90) of SSCrFCES for LPS lethality is achieved at 2 microM. These results demonstrate the endotoxin-neutralizing capability of SSCrFCES in vitro and in vivo and its potential use for the treatment of endotoxin-induced septic shock. PMID:10783139

Tan, N S; Ho, B; Ding, J L

2000-05-01

157

Urocortin increased LPS-induced endothelial permeability by regulating the cadherin-catenin complex via corticotrophin-releasing hormone receptor 2.  

PubMed

Urocortin (Ucn1), a member of corticotrophin-releasing hormone (CRH) family, has been reported to be upregulated in inflammatory diseases and function as an autocrine or paracrine inflammatory mediator. Growing evidence shows that Ucn1 increases the endothelial permeability in inflammatory conditions; however, the detailed mechanisms are not clear. In the present study, we investigated the mechanisms of increased endothelial permeability by Ucn1 in human umbilical vein endothelial cells (HUVECs) exposed to lipopolysaccharide (LPS). Pretreatment of HUVECs with Ucn1 increased the endothelial cell permeability, which was augmented by LPS synergistically. Significant downregulation of VE-cadherin expression was also observed. Moreover, Ucn1 increased phosphorylation of protein kinase D (PKD) and heat shock protein 27 (HSP27) in a time- and CRHR(2) -dependent manner. Inhibition of PKD and HSP27 drastically attenuated Ucn1-induced downregulation of VE-cadherin expression. Further investigations demonstrated that Ucn1 phosphorylated ?-catenin at Ser552 to disrupt the cadherin-catenin complex and hence promote the disassociation of ?-catenin and VE-cadherin. Disassociation of ?-catenin and VE-cadherin resulted in decreased VE-cadherin expression while on the contrary ?-catenin was increased, which may due to the inactivation of GSK-3?. Increased ?-catenin translocated into the nucleus and subsequently bound to TCF/LEF site, contributing to the elevated expression of vascular endothelial growth factor (VEGF). The above effects of Ucn1 were completely reversed by CRHR(2) receptor blocker, antisauvagine-30. Taken together, our data suggest that Ucn1 increase LPS-induced endothelial permeability by disrupting the VE-cadherin-?-catenin complex via activation of CRHR(2) and PKD-HSP27 signaling pathway. PMID:23168683

Wan, Rong; Guo, Rui; Chen, Cheng; Jin, Lai; Zhu, Chao; Zhang, Qichun; Xu, Youhua; Li, Shengnan

2013-06-01

158

Comparative analysis of the acute response of the trout, O. mykiss, head kidney to in vivo challenge with virulent and attenuated infectious hematopoietic necrosis virus and LPS-induced inflammation  

Microsoft Academic Search

BACKGROUND: The response of the trout, O. mykiss, head kidney to bacterial lipopolysaccharide (LPS) or active and attenuated infectious hematopoietic necrosis virus (IHNV and attINHV respectively) intraperitoneal challenge, 24 and 72 hours post-injection, was investigated using a salmonid-specific cDNA microarray. RESULTS: The head kidney response to i.p. LPS-induced inflammation in the first instance displays an initial stress reaction involving suppression

Simon MacKenzie; Joan C Balasch; Beatriz Novoa; Laia Ribas; Nerea Roher; Aleksei Krasnov; Antonio Figueras

2008-01-01

159

A decoy oligonucleotide to NF-?B delivered through inhalable particles prevents LPS-induced rat airway inflammation.  

PubMed

The inflammatory process plays a crucial role in the onset and progression of several lung pathologies, including cystic fibrosis (CF), and the involvement of NF-?B is widely recognized. The specific inhibition of NF-?B by decoy oligonucleotides delivered within the lung may be beneficial, although rationally designed systems are needed to optimize their pharmacological response. Prompted by this need, we have developed and tested in vivo an inhalable dry powder for the prolonged delivery of a decoy oligodeoxynucleotide to NF-?B (dec-ODN), consisting of large porous particles (LPPs) based on poly(lactic-co-glycolic) acid. First, LPPs containing dec-ODN (dec-ODN LPPs) were engineered to meet the aerodynamic criteria crucial for pulmonary delivery, to gain an effective loading of dec-ODN, to sustain its release, and to preserve its structural integrity in lung lining fluids. We then investigated the effects of dec-ODN LPPs in a rat model of lung inflammation induced by the intratracheal aerosolization of LPS from Pseudomonas aeruginosa. The results show that a single intratracheal insufflation of dec-ODN LPPs reduced the bronchoalveolar neutrophil infiltration induced by LPS for up to 72 hours, whereas naked dec-ODN was able to inhibit it only at 6 hours. The persistent inhibition of neutrophil infiltrate was associated with reduced NF-?B/DNA binding activity, as well as reduced IL-6, IL-8, and mucin-2 mRNA expression in lung homogenates. We consider it noteworthy that the developed LPPs, preventing the accumulation of neutrophils and NF-?B-related gene expression, may provide a new therapeutic option for the local treatment of inflammation associated with lung disease. PMID:23590300

De Stefano, Daniela; Coletta, Ciro; Bianca, Roberta d'Emmanuele di Villa; Falcone, Lucia; d'Angelo, Ivana; Ungaro, Francesca; Quaglia, Fabiana; Carnuccio, Rosa; Sorrentino, Raffaella

2013-08-01

160

Furanodien-6-one from Commiphora erythraea inhibits the NF-?B signalling and attenuates LPS-induced neuroinflammation.  

PubMed

We investigated the in vitro anti-inflammatory activity of 1(10),4-furanodien-6-one, one the most active compounds of the hexane extract of Commiphora erythraea (Ehrenb.) Engl., by exposing microglial BV-2 cells to lipopolysaccharide. We showed that furanodien-6-one pre-treatment restored cell viability and ROS to control levels while halving NO generation. Production of pro-inflammatory IL-6, IL-23, IL-17, TGF-?, and INF-?, significantly induced by LPS, was also markedly reduced by furanodien-6-one treatment. We further showed that furanodien-6-one protects primary neuronal cultures against the inflammatory/toxic insults of LPS-treated BV-2 conditioned media, indicating that furanodien-6-one exerts anti-inflammatory/cytoprotective effects in neuronal cells. We then investigated whether furanodien-6-one exerts anti-inflammatory properties in an in vivo model of microglial activation. In adult mice ip-injected with LPS we found that furanodien-6-one had strong cerebral anti-inflammatory properties by inhibiting liver and brain TNF? as well as IL-1? expression. Results were not unexpected since FTIR-metabolomic analyses showed that furanodien-6-one-treated mice had a reduced dissimilarity to control animals and that the response to LPS treatment was markedly modified by furanodien-6-one. In conclusion our data provide strong evidence of the anti-inflammatory properties of furanodien-6-one that could be exploited to counteract degenerative pathologies based on neuroinflammation. PMID:23357788

Bellezza, Ilaria; Mierla, Annalisa; Grottelli, Silvia; Marcotullio, Maria Carla; Messina, Federica; Roscini, Luca; Cardinali, Gianluigi; Curini, Massimo; Minelli, Alba

2013-01-26

161

Role of TLR signaling in Francisella tularensis-LPS-induced, antibody-mediated protection against Francisella tularensis challenge  

PubMed Central

Immunization with Ft-LPS provokes an antigen-specific, B-1a cell-derived antibody response that protects WT mice against an otherwise lethal challenge with Ft LVS. However, this same regimen offers limited protection to TLR2?/? mice, despite production of WT levels of anti-Ft-LPS antibodies. As Ft-LPS exhibits no TLR2 agonist activity, and macrophage-induced cytokine production in response to Ft LVS is overwhelmingly TLR2-dependent, we hypothesized that treatment of TLR2?/? mice with an alternative, MyD88-dependent TLR agonist would compensate for reduced recognition of Ft LVS in TLR2?/? mice and thereby, restore Ft-LPS-mediated protection. Administration of the nontoxic TLR4 agonist, synthetic Escherichia coli MPL, at the time of Ft-LPS immunization or Ft LVS challenge, fully protected TLR2?/? mice, whereas treatment of WT or TLR2?/? mice with MPL alone conferred partial protection. The TLR5 agonist, flagellin, also synergized with Ft-LPS to protect TLR2?/? mice from lethal Ft LVS challenge. In contrast to Ft LVS, Ft-LPS pretreatment failed to protect mice against i.n. challenge with Ft Schu S4, whereas MPL, administered in the absence or presence of Ft-LPS, conferred significant, albeit partial, protection. MPL treatment of macrophages increased the uptake of Ft LVS and decreased intracellular bacterial survival while shifting the macrophage-differentiation phenotype from “alternatively activated” to “classically activated”. Collectively, our data suggest that optimal, Ft-LPS-mediated protection against Ft LVS infection requires two discrete events, i.e., production of Ft-LPS-specific antibody, as well as TLR-mediated macrophage activation, to fully control Francisella infection.

Cole, Leah E.; Mann, Barbara J.; Shirey, Kari Ann; Richard, Katharina; Yang, Yang; Gearhart, Patricia J.; Chesko, Kirsty L.; Viscardi, Rose M.; Vogel, Stefanie N.

2011-01-01

162

Enzyme activity and acute phase proteins in milk utilized as indicators of acute clinical E. coli LPS-induced mastitis.  

PubMed

The importance of non-visual and on-line monitoring of udder health increases as the contact between humans and animals decreases, for example, in robotic milking systems. Several indicator systems have been introduced commercially, and a number of techniques are currently in use. This study describes the kinetics of seven indigenous milk parameters for monitoring udder inflammation in an Escherichia coli lipopolysaccharide (LPS, endotoxin)-induced mastitis model. Proportional milk from LPS-infused quarters was compared with milk from parallel quarters, which were placebo-treated with sterile 0.9% NaCl solution. Somatic cell counts (SCCs), the acute phase proteins (APP), that is, milk amyloid A (MAA) and haptoglobin (Hp), and the enzymes N-acetyl-?-D-glucosaminidase (NAGase), lactate dehydrogenase (LDH), alkaline phosphatase (AP) and acid phosphatase (AcP) were measured at fixed intervals during the period from -2 to +5 days after LPS and NaCl infusions. All parameters responded significantly faster and were more pronounced to the LPS infusions compared with the NaCl infusions. All parameters were elevated in the proportional milk collected at the first milking 7 h after infusion and developed a monophasic response, except Hp and MAA that developed biphasic response. SCC, LDH, NAGase and Hp peaked at 21 h followed by AP, AcP and MAA peaking at 31 h with the highest fold changes seen for MAA (23 780×), LDH (126×), NAGase (50×) and Hp (16×). In the recovery phase, AP, AcP and Hp reached base levels first, at 117 h, whereas LDH, NAGase and MAA remained elevated following the pattern of SCC. Minor increases of the milk parameters were also seen in the neighboring (healthy) quarters. Distinction between inflamed and healthy quarters was possible for all the parameters, but only for a limited time frame for AP and AcP. Hence, when tested in an LPS mastitis model, the enzymes LDH, NAGase and AP in several aspects performed equally with SCC and APP as inflammatory milk indicators of mastitis. Furthermore, these enzymes appear potent in the assessment of a valuable time sequence of inflammation, a necessary ingredient in modeling of programs in in-line surveillance systems. PMID:22445120

Larsen, T; Rřntved, C M; Ingvartsen, K L; Vels, L; Bjerring, M

2010-10-01

163

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

164

Insulin inhibits lipopolysaccharide-induced nitric oxide synthase expression in rat primary astrocytes.  

PubMed

Excessive production of nitric oxide (NO) by inducible nitric oxide synthase (iNOS) from reactive astrocytes and microglia may contribute to the development of many types of neurological diseases. Insulin has been shown to inhibit the expression of iNOS, in several organs and cell types. Although insulin and its receptors are present in the central nervous system, the effects of insulin on the iNOS pathway in the brain have not been determined. In this study, using lipopolysaccharide (LPS)-stimulated astrocytes as a model of reactive astrocytes, we investigated the effects of insulin on iNOS expression in activated astrocytes and the mechanism involved. The expression of iNOS was significantly upregulated by LPS in astrocytes. Insulin applied prior to LPS, dose-dependently inhibited LPS-induced iNOS gene expression and iNOS protein levels. In agreement with the suppressive effects of insulin on iNOS expression, insulin also inhibited LPS-induced iNOS activity and NO production. Moreover, insulin was found to significantly inhibit LPS-induced I?B-? phosphorylation and degradation, which led to a decrease in levels of the p65 subunit of NF-?B in the nuclear fraction. Therefore, insulin inhibited LPS-induced iNOS expression via suppressing NF-?B pathway in astrocytes. In addition, treatment with insulin had no effect on LPS-induced PKB phosphorylation. Based on our results, it is plausible to speculate that insulin in the brain may play a neuroprotective role in neurological disorders by controlling the release of NO via the regulation of iNOS expression in astrocytes. PMID:23416152

Li, Hui; Liu, Baoyi; Huang, Jingyang; Chen, Haili; Guo, Xiaosun; Yuan, Zhongrui

2013-02-14

165

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

2013-03-13

166

Potent anti-inflammatory effect of a novel furan-2,5-dione derivative, BPD, mediated by dual suppression of COX-2 activity and LPS-induced inflammatory gene expression via NF-?B inactivation  

PubMed Central

BACKGROUND AND PURPOSE We previously reported that 3-(benzo[d]-1,3-dioxol-5-yl)-4-phenylfuran-2,5-dione (BPD) showed strong inhibitory effects on PGE2 production. However, the exact mechanism for the anti-inflammatory effect of BPD is not completely understood. In this study, we investigated the molecular mechanism involved in the effects of BPD on inflammatory mediators in LPS-stimulated macrophages and animal models of inflammation. EXPERIMENTAL APPROACH The expressions of COX-2, inducible NOS (iNOS), TNF-?, IL-6 and IL-1?, in LPS-stimulated RAW 264.7 cells and murine peritoneal macrophages, were determined by Western blot and/or qRT-PCR, respectively. NF-?B activation was investigated by EMSA, reporter gene assay and Western blotting. Anti-inflammatory effects of BPD were evaluated in vivo in carrageenan-induced paw oedema in rats and LPS-induced septic shock in mice. KEY RESULTS BPD not only inhibited COX-2 activity but also reduced the expression of COX-2. In addition, BPD inhibited the expression of iNOS, TNF-?, IL-6 and IL-1? at the transcriptional level. BPD attenuated LPS-induced DNA-binding activity and the transcription activity of NF-?B; this was associated with a decrease in the phosphorylation level of inhibitory ?B-? (I?B-?) and reduced nuclear translocation of NF-?B. Furthermore, BPD suppressed the formation of TGF-?-activated kinase-1 (TAK1)/TAK-binding protein1 (TAB1), which was accompanied by a parallel reduction of phosphorylation of TAK1 and I?B kinase (IKK). Pretreatment with BPD inhibited carrageenan-induced paw oedema and LPS-induced septic death. CONCLUSION AND IMPLICATIONS Taken together, our data indicate that BPD is involved in the dual inhibition of COX-2 activity and TAK1-NF-?B pathway, providing a molecular basis for the anti-inflammatory properties of BPD.

Shin, Ji-Sun; Park, Seung-Jae; Ryu, Suran; Kang, Han Byul; Kim, Tae Woo; Choi, Jung-Hye; Lee, Jae-Yeol; Cho, Young-Wuk; Lee, Kyung-Tae

2012-01-01

167

Pseudoguaianolides isolated from Inula britannica var. chinenis as inhibitory constituents against inducible nitric oxide synthase.  

PubMed

Three pseudoguaianolide type sesquiterpenes, bigelovin (1), 2,3-dihydroaromaticin (2), and ergolide (3) were isolated as inhibitory constituents against inducible nitric oxide synthase (iNOS) from the flowers of Inula britannica var. chinensis. Bigelovin (1) exhibited a highly potent inhibitory activity on lipopolysaccharide (LPS)-induced iNOS in murine macrophage RAW 264.7 cells with an IC50 value of 0.46 mM, which is about 8 times more potent than the known selective inhibitor of iNOS, L-N6-(1-iminoethyl)lysine (IC50 3.49 microM). 2,3-Dihydroaromaticin (2) and ergolide (3) also exhibited potent inhibitory activities on LPS-induced iNOS with IC50 values of 1.05 and 0.69 microM, respectively. PMID:12009027

Lee, Hyun-Tai; Yang, Seung-Won; Kim, Kyeong Ho; Seo, Eun-Kyoung; Mar, Woongchon

2002-04-01

168

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

2013-04-11

169

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

2012-06-14

170

Inhibition of nitric oxide synthase accentuates endotoxin-induced sickness behavior in mice.  

PubMed

Sickness behavior appears to be the expression of a central motivational state that reorganizes an organism's priorities to cope with infectious pathogens. To evaluate the possible participation of nitric oxide (NO) in lipopolysaccharide-induced sickness behaviors, mice were submitted to the forced swim test (FST), open field test and dark-light box test. Food intake and corticosterone plasma levels were evaluated. Lipopolysaccharide (LPS, 100 ?g/kg; i.p.) administration increased the time spent floating in the FST and decreased locomotor activity in the open field. Indeed, treatment with LPS decreased the total number of transitions between the dark and light compartments of the apparatus. In addition, LPS reduced food intake and increased corticosterone levels. Pretreatment with L-NAME (30 mg/kg; i.p.) or aminoguanidine (50mg/kg; i.p.) accentuated the behavioral changes induced by LPS in the FST, open field and light-dark box tests as well as induced an increment in hypophagia and in corticosterone levels. These findings confirm previous observations that have reported LPS-induced sickness behaviors. In addition, they provide evidence that the synthesis of NO modulates changes in depressive-like and exploratory behaviors in mice, which is supported by the fact that NO synthase inhibitors also attenuate LPS-induced behavioral changes. In addition, the present study suggests that NO may have a protective role, acting in an inhibitory feedback manner to limit LPS-induced sickness behavior. PMID:23046850

Ribeiro, Deidiane E; Maiolini, Viviane M; Soncini, Roseli; Antunes-Rodrigues, José; Elias, Lucila L K; Vilela, Fabiana C; Giusti-Paiva, Alexandre

2012-10-06

171

Liquid perfluorochemical inhibits inducible nitric oxide synthase expression and nitric oxide formation in lipopolysaccharide-treated RAW 264.7 macrophages.  

PubMed

Partial liquid ventilation with various types of perfluorocarbon (PFC) has been shown to be beneficial in treating acute lung injury, a clinical outcome that may involve the anti-inflammatory activity of PFC. FC-77 is a type of PFC with relatively higher vapor pressure and evaporative loss than other PFCs during partial liquid ventilation. Overproduction of nitric oxide (NO) by inducible nitric oxide synthase (iNOS) has been proposed to play a crucial role in the pathogenesis of inflammatory diseases. However, whether the iNOS/NO pathway is affected by FC-77 is unknown. Thus, the aim of this study was to investigate whether FC-77 inhibits iNOS expression and NO production in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. We found that treatment with FC-77 significantly attenuated LPS-induced iNOS expression/activity and production of NO and reactive oxygen species (ROS). FC-77 also attenuated LPS-induced pro-inflammatory cytokine formation, but enhanced interleukin-10 production. Furthermore, the LPS-induced degradation of cytosolic IkappaB-alpha and activation of nuclear transcription factor-kappaB (NF-kappaB) were also inhibited by FC-77. In conclusion, the present study is the first to demonstrate that FC-77 decreases LPS-induced NO production in macrophages, which may be associated with the suppression of pro-inflammatory cytokines, and ROS production, as well as NF-kappaB activation. These results also provide a novel explanation for its anti-inflammatory activity. PMID:19834286

Chang, Li-Ping; Lai, Yuan-Shu; Wu, Chang-Jer; Chou, Tz-Chong

2009-10-01

172

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.

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

2013-01-01

173

Pseudoguaianolides isolated from inula britannica var. chinenis as inhibitory constituents against inducible nitric oxide synthase  

Microsoft Academic Search

Three pseudoguaianolide type sesquiterpenes, bigelovin (1), 2,3-dihydroaromaticin (2), and ergolide (3) were isolated as inhibitory\\u000a constituents against inducible nitric oxide synthase (iNOS) from the flowers ofInula britannica var. chinensis. Bigelovin (1) exhibited a highly potent inhibitory activity on lipopolysaccharide (LPS)-induced iNOS in murine macrophage\\u000a RAW 264.7 cells with an IC50 value of 0.46 mM, which is about 8 times more

Hyun-Tai Lee; Seung-Won Yang; Kyeong Ho Kim; Eun-Kyoung Seo; Woongchon Mar

2002-01-01

174

Chamomile, an anti-inflammatory agent inhibits inducible nitric oxide synthase expression by blocking RelA/p65 activity  

PubMed Central

Chamomile has long been used in traditional medicine for the treatment of inflammation-related disorders. In this study we aimed to investigate the inhibitory effects of chamomile on nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) expression, and to explore its potential anti-inflammatory mechanisms using RAW 264.7 macrophages. Chamomile treatment inhibited LPS-induced NO production and significantly blocked IL-1? , IL-6 and TNF?-induced NO levels in RAW 264.7 macrophages. Chamomile caused reduction in LPS-induced iNOS mRNA and protein expression. In RAW 264.7 macrophages, LPS-induced DNA binding activity of RelA/p65 was significantly inhibited by chamomile, an effect that was mediated through the inhibition of IKK? , the upstream kinase regulating NF-? B/Rel activity, and degradation of inhibitory factor-? B. These results demonstrate that chamomile inhibits NO production and iNOS gene expression by inhibiting RelA/p65 activation and supports the utilization of chamomile as an effective anti-inflammatory agent.

Bhaskaran, Natarajan; Shukla, Sanjeev; Srivastava, Janmejai K; Gupta, Sanjay

2010-01-01

175

Inhibition of inducible nitric oxide synthase and cyclooxygenase II by Platycodon grandiflorum saponins via suppression of nuclear factor-?B activation in RAW 264.7 cells  

Microsoft Academic Search

Saponins are glycosidic compounds present in many edible and inedible plants. They exhibit potent biological activities in mammalian systems, including several beneficial effects such as anti-inflammation and immunomodulation. In this study, we investigated the effects of seven platycodin saponins on the activities of inducible nitric oxide synthase (iNOS) and cyclooxygenase II (COX-2) in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. We found

Kwang Seok Ahn; Eun Jung Noh; Hai Lin Zhao; Sang Hoon Jung; Sam Sik Kang; Yeong Shik Kim

2005-01-01

176

Role of Nitric Oxide in Lipopolysaccharide-Induced Hepatic Injury in D-Galactosamine-Sensitized Mice as an Experimental Endotoxic Shock Model  

Microsoft Academic Search

The role of nitric oxide (NO) in lipopolysaccharide (LPS)-induced hepatic injury was studied in D-galac- tosamine (D-GalN)-sensitized mice. The inducible isoform of NO synthase (iNOS) was immunohistochemically detected on hepatocytes around blood vessels in livers of mice injected with D-GalN and LPS not on hepatocytes in mice injected with D-GalN or LPS alone, although mRNA for iNOS was found in

AKIKO MORIKAWA; YUTAKA KATO; TUYOSHI SUGIYAMA; NAOKI KOIDE; DIPSHIKA CHAKRAVORTTY; TOMOAKI YOSHIDA; TAKASHI YOKOCHI

1999-01-01

177

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.

1995-01-01

178

The nitric oxide hypothesis of aging  

Microsoft Academic Search

Nitric oxide (NO), generated by endothelial (e) NO synthase (NOS) and neuronal (n) NOS, plays a ubiquitous role in the body in controlling the function of almost every, if not every, organ system. Bacterial and viral products, such as bacterial lipopolysaccharide (LPS), induce inducible (i) NOS synthesis that produces massive amounts of NO toxic to the invading viruses and bacteria,

S. M McCann; J Licinio; M.-L Wong; W. H Yu; S Karanth; V Rettorri

1998-01-01

179

Inhibition of nitric oxide production and inducible nitric oxide synthase expression by a polymethoxyflavone from young fruits of Citrus unshiu in rat primary astrocytes.  

PubMed

Abnormal activation of astrocytes (e.g., the overproduction of cytokines and nitric oxide) is relevant to neurodegenerative disease. It is important, therefore, to search for inhibitors of the abnormal activation of astrocytes that can be derived from natural substances. This study focused on the effects of extracts from young fruits of Citrus unshiu on lipopolysaccharide (LPS)-induced nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) expression in rat primary astrocytes. The methanol extract of young citrus inhibited NO production in a concentration-dependent manner. After reverse-phase extraction of the extract, we found that polymethoxyflavone, nobiletin, 3,5,6,7,8,3',4'-heptamethoxyflavone, and tangeletin inhibited NO production by primary astrocytes. These polymethoxyflavones also inhibited LPS-induced iNOS protein and mRNA expression by suppressing nuclear factor-?B (NF-?B) activation and p38-mitogen-activated protein kinase (MAPK) phosphorylation. To evaluate possible applications of these neuroprotective agents in vivo, we examined the effects of young citrus fruit on delayed neurodegeneration in hippocampal CA1 neurons of the Mongolian gerbil after global ischemia. Oral administration of young citrus fruit significantly suppressed delayed neuronal death in hippocampal CA1 neurons. This suggests a possible application of young citrus fruit as a neuroprotective agent. PMID:23047093

Ihara, Hideshi; Yamamoto, Hideyuki; Ida, Tomoaki; Tsutsuki, Hiroyasu; Sakamoto, Tatsuji; Fujita, Tomoyuki; Okada, Toshiya; Kozaki, Shunji

2012-10-07

180

Inhibitory effects of natural sesquiterpenoids isolated from the rhizomes of Curcuma zedoaria on prostaglandin E2 and nitric oxide production.  

PubMed

Beta-turmerone and ar-turmerone, sesquiterpenoids isolated from the rhizome of Curcuma zedoaria, inhibited lipopolysaccharide (LPS)-induced prostaglandin E 2 production in cultured mouse macrophage cell RAW 264.7 in a dose-dependent manner (IC 50 = 7.3 microM for beta-turmerone; IC 50 = 24.0 microM for ar-turmerone). In addition, these compounds exhibited inhibitory effects on LPS-induced nitric oxide production in the cell system. PMID:12094302

Hong, Chae Hee; Noh, Min Soo; Lee, Woo Young; Lee, Sang Kook

2002-06-01

181

Role of SelS in lipopolysaccharide-induced inflammatory response in hepatoma HepG2 cells  

Microsoft Academic Search

To investigate the role of SelS in bacterial lipopolysaccharide (LPS) induced inflammatory response, some parameters in LPS-stimulated HepG2 cells were comparatively studied fore-and-aft SelS silence. LPS induced the decreases of cytoplasmic glutathione peroxidase (GPx-1) mRNA expression and activity, and the increases of reactive oxygen species (ROS) level, intracellular and extracellular nitric oxide (NO) levels, inducible nitric oxide synthase (iNOS) mRNA

Jinhong Zeng; Shaoqing Du; Jun Zhou; Kaixun Huang

2008-01-01

182

Peroxynitrite generated by inducible nitric oxide synthase and NADPH oxidase mediates microglial toxicity to oligodendrocytes  

PubMed Central

Reactive microglia in the CNS have been implicated in the pathogenesis of white matter disorders, such as periventricular leukomalacia and multiple sclerosis. However, the mechanism by which activated microglia kill oligodendrocytes (OLs) remains elusive. Here we show that lipopolysaccharide (LPS)-induced death of developing OLs is caused by microglia-derived peroxynitrite, the reaction product of nitric oxide (NO) and superoxide anion. Blocking peroxynitrite formation with nitric oxide synthase inhibitors, superoxide dismutase mimics, or a decomposition catalyst abrogated the cytotoxicity. Only microglia, but not OLs, expressed inducible NO synthase (iNOS) after LPS challenge; microglia from iNOS knockout mice were not cytotoxic upon activation. The molecular source for superoxide was identified as the superoxide-generating enzyme NADPH oxidase. The oxidase was activated upon LPS exposure, and its inhibition prevented microglial toxicity toward OLs. Furthermore, microglia isolated from mice deficient in the catalytic component of the oxidase, gp91phox, failed to induce cell death. Our results reveal a role for NADPH oxidase in LPS-induced OL death and suggest that peroxynitrite produced by iNOS and NADPH oxidase in activated microglia may play an important role in the pathogenesis of white matter disorders.

Li, Jianrong; Baud, Olivier; Vartanian, Timothy; Volpe, Joseph J.; Rosenberg, Paul A.

2005-01-01

183

Upstream NF-?B Site Is Required for the Maximal Expression of Mouse Inducible Nitric Oxide Synthase Gene in Interferon-? plus Lipopolysaccharide-Induced RAW 264.7 Macrophages  

Microsoft Academic Search

Transient transfection assays with various deletion mutants of the mouse inducible nitric oxide synthase (iNOS) promoter linked to a CAT reporter gene demonstrated that, besides the downstream NF-?B site, the region from ?973 to ?925 which contains a potential binding site for NF-?B (upstream NF-?B site) also mediated lipopolysaccharide (LPS)-inducibility in mouse macrophage cell line RAW 264.7. Site-specific mutation of

Yong-Man Kim; Bok-Soo Lee; Kun-Yeong Yi; Sang-Gi Paik

1997-01-01

184

Differential migration, LPS-induced cytokine, chemokine and NO expression in immortalized BV-2 and HAPI cell lines and primary microglial cultures  

PubMed Central

Microglial cells are hematopoietically derived monocytes of the CNS and serve important neuromodulatory, neurotrophic and neuroimmune roles. Following insult to the CNS, microglia develop a reactive phenotype, migrate to the site of injury, proliferate, and release a range of proinflammatory, anti-inflammatory and neurotrophic factors. Isolation of primary microglial cell cultures has been an integral step in elucidating the many roles of these cells. In addition to primary microglial cells, several immortalized cell lines have been created to model primary microglia in vitro, including murine derived BV-2 cells and rat derived HAPI cells. Here we compare rat primary microglial, BV-2 and HAPI cells in experiments assessing migration, expression of activation markers and production and release of NO (nitric oxide), cytokines and chemokines. BV-2 and HAPI cells responded similarly to primary microglia in experiments assessing migration, Iba1 expression, and NO release. However, BV-2 and HAPI cells did not model primary microglia in experiments assessing TNF?, IL-1?, IL-6 and MCP-1 expression and release and pERK 44/42 (extracellular receptor kinase) expression following LPS treatment. These results indicate that BV-2 and HAPI cell cultures only partially model primary microglia and that their use should therefore be carefully considered.

Horvath, Ryan J.; Nutile-McMenemy, Nancy; Alkaitis, Matthew S.; De Leo, Joyce A.

2008-01-01

185

Inhibitory Effects of Ethyl Acetate Extract of Andrographis paniculata on NF-?B Trans-Activation Activity and LPS-Induced Acute Inflammation in Mice.  

PubMed

This study was to investigate anti-inflammatory effect of Andrographis paniculata (Burm. f.) Nees (Acanthaceae) (AP). The effects of ethyl acetate (EtOAc) extract from AP on the level of inflammatory mediators were examined first using nuclear factor kappa B (NF-?B) driven luciferase assay. The results showed that AP significantly inhibited NF-?B luciferase activity and tumor necrosis factor ? (TNF-?), interleukin 6 (IL-6), macrophage inflammatory protein-2 (MIP-2) and nitric oxide (NO) secretions from lipopolysaccharide (LPS)/interferon-? stimulated Raw264.7 cells. To further evaluate the anti-inflammatory effects of AP in vivo, BALB/c mice were tube-fed with 0.78 (AP1), 1.56 (AP2), 3.12 (AP3) and 6.25 (AP4)?mg?kg(-1) body weight (BW)/day in soybean oil, while the control and PDTC (pyrrolidine dithiocarbamate, an anti-inflammatory agent) groups were tube-fed with soybean oil only. After 1 week of tube-feeding, the PDTC group was injected with 50?mg?kg(-1) BW PDTC and 1 h later, all of the mice were injected with 15?mg?kg(-1) BW LPS. The results showed that the AP1, AP2, AP3 and PDTC groups, but not AP4, had significantly higher survival rate than the control group. Thus, the control, AP1, AP2, AP3 and PDTC groups were repeated for in vivo parameters. The results showed that the AP and PDTC groups had significantly lower TNF-?, IL-12p40, MIP-2 or NO in serum or peritoneal macrophages and infiltration of inflammatory cells into the lung of mice. The AP1 group also had significantly lower MIP-2 mRNA expression in brain. This study suggests that AP can inhibit the production of inflammatory mediators and alleviate acute hazards at its optimal dosages. PMID:19745004

Chao, Wen-Wan; Kuo, Yueh-Hsiung; Hsieh, Shie-Liang; Lin, Bi-Fong

2011-02-14

186

Inhibitory Effects of Ethyl Acetate Extract of Andrographis paniculata on NF-?B Trans-Activation Activity and LPS-Induced Acute Inflammation in Mice  

PubMed Central

This study was to investigate anti-inflammatory effect of Andrographis paniculata (Burm. f.) Nees (Acanthaceae) (AP). The effects of ethyl acetate (EtOAc) extract from AP on the level of inflammatory mediators were examined first using nuclear factor kappa B (NF-?B) driven luciferase assay. The results showed that AP significantly inhibited NF-?B luciferase activity and tumor necrosis factor ? (TNF-?), interleukin 6 (IL-6), macrophage inflammatory protein-2 (MIP-2) and nitric oxide (NO) secretions from lipopolysaccharide (LPS)/interferon-? stimulated Raw264.7 cells. To further evaluate the anti-inflammatory effects of AP in vivo, BALB/c mice were tube-fed with 0.78 (AP1), 1.56 (AP2), 3.12 (AP3) and 6.25 (AP4)?mg?kg?1 body weight (BW)/day in soybean oil, while the control and PDTC (pyrrolidine dithiocarbamate, an anti-inflammatory agent) groups were tube-fed with soybean oil only. After 1 week of tube-feeding, the PDTC group was injected with 50?mg?kg?1 BW PDTC and 1 h later, all of the mice were injected with 15?mg?kg?1 BW LPS. The results showed that the AP1, AP2, AP3 and PDTC groups, but not AP4, had significantly higher survival rate than the control group. Thus, the control, AP1, AP2, AP3 and PDTC groups were repeated for in vivo parameters. The results showed that the AP and PDTC groups had significantly lower TNF-?, IL-12p40, MIP-2 or NO in serum or peritoneal macrophages and infiltration of inflammatory cells into the lung of mice. The AP1 group also had significantly lower MIP-2 mRNA expression in brain. This study suggests that AP can inhibit the production of inflammatory mediators and alleviate acute hazards at its optimal dosages.

Chao, Wen-Wan; Kuo, Yueh-Hsiung; Hsieh, Shie-Liang; Lin, Bi-Fong

2011-01-01

187

Toll-like receptor 3 ligand attenuates LPS-induced liver injury by down-regulation of toll-like receptor 4 expression on macrophages.  

PubMed

This study demonstrates that pretreatment with polyinosinic-polycytidylic acid (poly I:C) significantly decreased the mortality and liver injury caused by injection of lipopolysaccharide (LPS) in the presence of d-galactosamine (d-GalN) in C57BL/6 mice. Depletion of natural killer, natural killer T, and T cells did not change the protective effect of poly I:C on LPS/d-GalN-induced liver injury in vivo. However, depletion of macrophages abolished LPS/d-GalN-induced fulminant hepatitis, which could be restored by adoptive transfer of macrophages but not by transfer of poly I:C-treated macrophages. Treatment with poly I:C down-regulated the expression of the toll-like receptor 4 (TLR4) on macrophages and reduced the sensitivity of macrophages (Kupffer cells and peritoneal macrophages from C57BL/6 mice, or RAW264.7 cells) to LPS stimulation. Poly I:C pretreatment also impaired the signaling of mitogen-activated protein kinases and NF-kappaB induced by LPS in RAW264.7 cells. Blockade of TLR3 with a TLR3 antibody abolished poly I:C down-regulation of TLR4 expression and LPS stimulation of TNF-alpha production in RAW264.7 cells. Taken together, our findings suggest that activation of TLR3 by its ligand, poly I:C, induced LPS tolerance by down-regulation of TLR4 expression on macrophages. PMID:16287979

Jiang, Wei; Sun, Rui; Wei, Haiming; Tian, Zhigang

2005-11-15

188

A Role of Cell Apoptosis in Lipopolysaccharide (LPS)-induced Nonlethal Liver Injury in d -galactosamine ( d -GalN)-sensitized Rats  

Microsoft Academic Search

Lipopolysaccharide (LPS) is implicated in the pathology of acute liver injury and can induce lethal liver failure when simultaneously\\u000a administered with d-galactosamine (d-GalN). At the present time, nonlethal liver failure, the liver injury of clinical implication, is incompletely understood\\u000a following challenge by low-dose LPS\\/d-GalN. We report here our investigation of the effects of liver injury following a nonlethal dose LPS\\/d-GalN

Liang-Ming Liu; Ji-Xiang Zhang; Jie Luo; Hong-Xing Guo; Huan Deng; Jian-Yong Chen; Sui-Lin Sun

2008-01-01

189

Toll-like receptor 3 ligand attenuates LPS-induced liver injury by down-regulation of toll-like receptor 4 expression on macrophages  

Microsoft Academic Search

This study demonstrates that pretreatment with polyinosinic-polycytidylic acid (poly I:C) significantly decreased the mortality and liver injury caused by injection of lipopolysaccharide (LPS) in the presence of D-galactosamine (D-GalN) in C57BL\\/6 mice. Depletion of natural killer, natural killer T, and T cells did not change the protective effect of poly I:C on LPS\\/D-GalN-induced liver injury in vivo. However, depletion of

Wei Jiang; Rui Sun; Haiming Wei; Zhigang Tian

2005-01-01

190

Rosmarinic acid, a major polyphenolic component of Perilla frutescens, reduces lipopolysaccharide (LPS)-induced liver injury in d-galactosamine ( d-GalN)-sensitized mice  

Microsoft Academic Search

The protective activity of rosmarinic acid from Perilla frutescens on liver injury induced by LPS in d-GalN-sensitized mice was examined. We also investigated the effects of antitumor necrosis factor-? antibody (anti-TNF), superoxide dismutase (SOD), and aminoguanidine (AG) on this model in order to elucidate the mechanism of rosmarinic acid protection. Perilla extract (PE) and rosmarinic acid (RA) treatments significantly reduced

Naomi Osakabe; Akiko Yasuda; Midori Natsume; Chiaki Sanbongi; Yoji Kato; Toshihiko Osawa; Toshikazu Yoshikawa

2002-01-01

191

Inflammatory Animal Model for Parkinson's Disease: The Intranigral Injection of LPS Induced the Inflammatory Process along with the Selective Degeneration of Nigrostriatal Dopaminergic Neurons  

PubMed Central

We have developed an animal model of degeneration of the nigrostriatal dopaminergic neurons, the neuronal system involved in Parkinson's disease (PD). The implication of neuroinflammation on this disease was originally established in 1988, when the presence of activated microglia in the substantia nigra (SN) of parkinsonians was reported by McGeer et al. Neuroinflammation could be involved in the progression of the disease or even has more direct implications. We injected 2??g of the potent proinflammatory compound lipopolysaccharide (LPS) in different areas of the CNS, finding that SN displayed the highest inflammatory response and that dopaminergic (body) neurons showed a special and specific sensitivity to this process with the induction of selective dopaminergic degeneration. Neurodegeneration is induced by inflammation since it is prevented by anti-inflammatory compounds. The special sensitivity of dopaminergic neurons seems to be related to the endogenous dopaminergic content, since it is overcome by dopamine depletion. Compounds that activate microglia or induce inflammation have similar effects to LPS. This model suggest that inflammation is an important component of the degeneration of the nigrostriatal dopaminergic system, probably also in PD. Anti-inflammatory treatments could be useful to prevent or slow down the rate of dopaminergic degeneration in this disease.

Machado, A.; Herrera, A. J.; Venero, J. L.; Santiago, M.; de Pablos, R. M.; Villaran, R. F.; Espinosa-Oliva, A. M.; Arguelles, S.; Sarmiento, M.; Delgado-Cortes, M. J.; Maurino, R.; Cano, J.

2011-01-01

192

Inhibition of soluble epoxide hydrolase reduces LPS-induced thermal hyperalgesia and mechanical allodynia in a rat model of inflammatory pain  

PubMed Central

Soluble epoxide hydrolases catalyze the hydrolysis of epoxides in acyclic systems. In man this enzyme is the product of a single copy gene (EPXH-2) present on chromosome 8. The human sEH is of interest due to emerging roles of its endogenous substrates, epoxygenated fatty acids, in inflammation and hypertension. One of the consequences of inhibiting sEH in rodent inflammation models is a profound decrease in the production of pro-inflammatory and proalgesic lipid metabolites including prostaglandins. This prompted us to hypothesize that sEH inhibitors may have antinociceptive properties. Here we tested if sEH inhibitors can reduce inflammatory pain. Hyperalgesia was induced by intraplantar LPS injection and sEH inhibitors were delivered topically. We found that two structurally dissimilar but equally potent sEH inhibitors can be delivered through the transdermal route and that sEH inhibitors effectively attenuate thermal hyperalgesia and mechanical allodynia in rats treated with LPS. In addition we show that epoxydized arachidonic acid metabolites, EETs, are also effective in attenuating thermal hyperalgesia in this model. In parallel with the observed biological activity metabolic analysis of oxylipids showed that inhibition of sEH resulted with a decrease in PGD2 levels and sEH generated degradation products of linoleic and arachidonic acid metabolites with a concomitant increase in epoxides of linoleic acid. These data show that inhibition of sEH may become a viable therapeutic strategy to attain analgesia.

Inceoglu, Bora; Jinks, Steven L.; Schmelzer, Kara R.; Waite, Troy; Kim, In Hae; Hammock, Bruce D.

2007-01-01

193

[Effect of geniposide on LPS-induced activation of TLR4-NF-?B pathway in RAW264.7 macrophage cell line].  

PubMed

Objective To study the anti-inflammatory mechanism of geniposide and observe the effect of geniposide on the expression of Toll-like receptor 4 (TLR4), the activity of NF-?B, and the release of pro-inflammatory cytokines- TNF-?, IL-1, and IL-6-in the RAW264.7 macrophages treated with lipopolysaccharide (LPS). Methods There were three experimental groups, including the control group, LPS group and LPS combined with geniposide group in this study. RAW264.7 macrophage cells were treated with LPS to induce cellular inflammation. Cell proliferation was measured by CCK-8. The concentrations of TNF-?, IL-1, and IL-6 in cell culture media were measured by ELISA. mRNA levels of TLR4 and P65 were examined by real-time PCR. The protein levels of p-I?B, P65, p-P65 and TLR4 were detected by Western blotting. Results Geniposide had no effect on cell proliferation. However, geniposide down-regulated the expression of TNF-?, IL-1, and IL-6, and also inhibited the expression of TLR4 and the activity of NF-?B. Conclusion Geniposide exerts its anti-inflammatory effect through inhibiting the activity of NF-?B in the TLR4-NF-?B pathway in macrophages. PMID:24103259

Huang, Lihua; Wang, Chunjie; Naren, Gaowa; Aori, Gele

2013-10-01

194

Induction of Golli-MBP Expression in CNS Macrophages During Acute LPS-Induced CNS Inflammation and Experimental Autoimmune Encephalomyelitis (EAE)  

PubMed Central

Microglia are the tissue macrophages of the CNS. Microglial activation coupled with macrophage infiltration is a common feature of many classic neurodegenerative disorders. The absence of cell-type specific markers has confounded and complicated the analysis of cell-type specific contributions toward the onset, progression, and remission of neurodegeneration. Molecular screens comparing gene expression in cultured microglia and macrophages identified Golli-myelin basic protein (MBP) as a candidate molecule enriched in peripheral macrophages. In situ hybridization analysis of LPS/IFNg and experimental autoimmune encephalomyelitis (EAE)–induced CNS inflammation revealed that only a subset of CNS macrophages express Golli-MBP. Interestingly, the location and morphology of Golli-MBP+ CNS macrophages differs between these two models of CNS inflammation. These data demonstrate the difficulties of extending in vitro observations to in vivo biology and concretely illustrate the complex heterogeneity of macrophage activation states present in region- and stage-specific phases of CNS inflammation. Taken altogether, these are consistent with the emerging picture that the phenotype of CNS macrophages is actively defined by their molecular interactions with the CNS microenvironment.

Papenfuss, Tracey L.; Thrash, J. Cameron; Danielson, Patria E.; Foye, Pamela E.; HIlbush, Brian S.; Sutcliffe, J. Gregor; Whitacre, Caroline C.; Carson, Monica J.

2009-01-01

195

Microarray and pathway analysis reveal distinct mechanisms underlying cannabinoid-mediated modulation of LPS-induced activation of BV-2 microglial cells.  

PubMed

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

2013-04-24

196

Comparative analysis of the acute response of the trout, O. mykiss, head kidney to in vivo challenge with virulent and attenuated infectious hematopoietic necrosis virus and LPS-induced inflammation  

PubMed Central

Background The response of the trout, O. mykiss, head kidney to bacterial lipopolysaccharide (LPS) or active and attenuated infectious hematopoietic necrosis virus (IHNV and attINHV respectively) intraperitoneal challenge, 24 and 72 hours post-injection, was investigated using a salmonid-specific cDNA microarray. Results The head kidney response to i.p. LPS-induced inflammation in the first instance displays an initial stress reaction involving suppression of major cellular processes, including immune function, followed by a proliferative hematopoietic-type/biogenesis response 3 days after administration. The viral response at the early stage of infection highlights a suppression of hematopoietic and protein biosynthetic function and a stimulation of immune response. In fish infected with IHNV a loss of cellular function including signal transduction, cell cycle and transcriptional activity 72 hours after infection reflects the tissue-specific pathology of IHNV infection. attIHNV treatment on the other hand shows a similar pattern to native IHNV infection at 24 hours however at 72 hours a divergence from the viral response is seen and replace with a recovery response more similar to that observed for LPS is observed. Conclusion In conclusion we have been able to identify and characterise by transcriptomic analysis two different types of responses to two distinct immune agents, a virus, IHNV and a bacterial cell wall component, LPS and a 'mixed' response to an attenuated IHNV. This type of analysis will lead to a greater understanding of the physiological response and the development of effective immune responses in salmonid fish to different pathogenic and pro-inflammatory agents.

MacKenzie, Simon; Balasch, Joan C; Novoa, Beatriz; Ribas, Laia; Roher, Nerea; Krasnov, Aleksei; Figueras, Antonio

2008-01-01

197

A feedback loop in PPAR?-adenosine A2A receptor signaling inhibits inflammation and attenuates lung damages in a mouse model of LPS-induced acute lung injury.  

PubMed

Although peroxisome proliferator-activated receptor-? (PPAR?) and adenosine A2A receptor (A2AR) are reported to be anti-inflammatory factors in acute lung injury (ALI), their internal link and synergic or antagonistic effect after activation are poorly understood. Here, we found that PPAR? and A2AR could upregulate the mRNA and protein expressions of each other in lung tissues of LPS-induced mouse ALI model and murine macrophages. Further investigation demonstrated that PPAR? upregulated A2AR expression by directly binding to a DR10 response element (-218 to -197) within A2AR gene promoter region. Instead of directly interacting with PPAR?, A2AR stimulated PPAR? expression via protein kinase A (PKA)-cAMP response element binding protein (CREB) signaling by provoking the binding of CREB to a cAMP responsive element (CRE)-like site in PPAR? gene promoter region. In addition, combination of PPAR? and A2AR agonists was found to exert obviously better effect on suppressing neutrophil infiltration and inflammatory cytokine expressions, attenuating lung edema, pathological changes and improving lung function of blood gas exchange than their single application. These findings reveal a novel functional positive feedback loop between PPAR? and A2AR signaling to potentialize their effect on inhibiting inflammation and attenuating lung damages in ALI. It suggests that targeting this PPAR?-A2AR signaling rather than PPAR? or A2AR alone may be a more attractive and efficient potential therapeutic strategy for ALI. PMID:23712033

He, Xie; Hu, Jian-Lin; Li, Jun; Zhao, Li; Zhang, Yan; Zeng, Yi-Jun; Dai, Shuang-Shuang; He, Feng-Tian

2013-05-24

198

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

199

SRC-FAMILY TYROSINE KINASE INHIBITOR (PP1) SUPPRESSES LPS-INDUCED EXPRESSION OF INDUCIBLE NITRIC OXIDE SYNTHASE MEDIATED THROUGH THE INHIBITION OF INTERFERON B EXPRESSION IN MACROPHAGES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Bacterial lipopolysaccharide (LPS) activates Toll-like recptor (TLR4) leading to expression of inflammatory gene products. Non-receptor type Src-family tyrosine kinases are activated by LPS and associated with CD14, a co-receptor for LPS in monocytes and macrophages. Therefore, we determined the ro...

200

Suppression of lipopolysaccharide-induced expression of inducible nitric oxide synthase by brazilin in RAW 264.7 macrophage cells.  

PubMed

Brazilin (7,11b-dihydrobenz[b]indeno[1,2-d]pyran-3,6a,9,10 (6H)-tetrol) isolated from Caesalpinia sappan has been known as a natural red pigment. Many studies suggest that inducible isoform of nitric oxide synthase (NOS) plays an important role in inflammation and carcinogenesis. On this line, we evaluated the inhibitory effect of brazilin on nitric oxide (NO) production and investigated its mechanism of action. As a result, brazilin exhibited the inhibitory effect on lipopolysaccharide (LPS)-stimulated NO production in a dose-dependent manner (IC50=24.3 microM). In addition, brazilin suppressed LPS-induced iNOS protein and mRNA expression in RAW 264.7 macrophage cells, indicating that the inhibitory activity of brazilin possibly involved in the regulation of iNOS expression. To further investigate the mechanism responsible for the suppression of iNOS gene expression by brazilin, the effect of brazilin on LPS-induced transcription factors nuclear factor-kappaB (NF-kappaB) and activator protein-1 (AP-1) activation was examined. The DNA binding activity of NF-kappaB and AP-1 stimulated LPS was inhibited by treatment of brazilin in a dose-dependent manner, suggesting that brazilin-mediated inhibition of NO production might be associated with the regulation of transcription factors NF-kappaB and AP-1. Taken together, these findings suggest that the suppressive effect of iNOS gene expression by brazilin might provide one possible mechanism for its anti-inflammatory and cancer chemopreventive activity. PMID:15862806

Bae, In-Kyung; Min, Hye-Young; Han, Ah-Reum; Seo, Eun-Kyoung; Lee, Sang Kook

2005-04-15

201

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

202

Anti-inflammatory effects of sinapic acid through the suppression of inducible nitric oxide synthase, cyclooxygase-2, and proinflammatory cytokines expressions via nuclear factor-kappaB inactivation.  

PubMed

To investigate the anti-inflammatory potential of sinapic acid as well as the underlying mechanism involved, we studied the inhibitory effect of sinapic acid on the production of pro-inflammatory mediators in vitro and then evaluated its in vivo anti-inflammatory effect. Sinapic acid inhibited lipopolysaccharide (LPS)-induced nitric oxide (NO), prostaglandin E 2 (PGE 2), tumor necrosis factor (TNF)-alpha, and interleukin (IL)-1beta production in a dose-dependent manner. Consistent with these findings, sinapic acid inhibited LPS-induced expressions of inducible nitric oxide synthase (iNOS) and cyclooxygase (COX)-2 at the protein levels, and iNOS, COX-2, TNF-alpha, and IL-1beta mRNA expression in RAW 264.7 macrophages, as determined by Western blotting and reverse-transcribed polymerase chain reaction, respectively. Sinapic acid suppressed the LPS-induced activation of nuclear factor-kappaB (NF-kappaB), a transcription factor pivotal necessary for pro-inflammatory mediators, such as iNOS, COX-2, TNF-alpha, and IL-1beta. This effect was accompanied by a parallel reduction of the nuclear translocation of p65 and p50 NF-kappaB subunits, as well as IkappaB-alpha degradation and phosphorylation. The effects of sinapic acid on acute phase inflammation were investigated on serotonin- and carrageenan-induced paw edema and compared with indomethacin (10 mg/kg, p.o.) or ibuprofen (100 mg/kg, p.o.). Maximum inhibitions of 34.2 and 44.5% were observed at a concentration of 30 mg/kg for serotonin- and carrageenan-induced paw edema, respectively. These results suggest that the suppressions of the expressions of iNOS, COX-2, TNF-alpha, and IL-1beta via NF-kappaB inactivation are responsible for the anti-inflammatory effects of sinapic acid. PMID:18841975

Yun, Kyung-Jin; Koh, Duck-Jae; Kim, Shi-Hye; Park, Seung Jae; Ryu, Jong Hoon; Kim, Deog-Gon; Lee, Jin-Yong; Lee, Kyung-Tae

2008-10-09

203

Anandamide regulates lipopolysaccharide-induced nitric oxide synthesis and tissue damage in the murine uterus.  

PubMed

In women, the association between chronic marijuana smoking and early miscarriage has long been known. Anandamide, a major endocannabinoid, mimics some of the psychotropic, hypnotic and analgesic effects of Delta(9)-tetrahydrocannabinol, the psychoactive component of marijuana. The uterus contains the highest concentrations of anandamide yet discovered in mammalian tissues and this suggests that it might play a role in reproduction. The production of small amounts of nitric oxide (NO) regulates various physiological events including implantation and myometrial relaxation, but in an inflammatory setting such as sepsis, NO has toxic effects as it is a free radical. The results presented in this study indicate that anandamide modulates NO production induced by lipopolysaccharide (LPS) in an in-vitro murine model. It was shown that LPS-induced NO synthesis and tissue damage were mediated by anandamide, as a cannabinoid receptor type I antagonist could block the effect of LPS (P < 0.001). This endotoxin inhibited anandamide uterine degradation (P < 0.05) and increased the expression of one of its synthesizing enzymes (P < 0.05). Contrary to the known anti-inflammatory and protective effects, in this model anandamide seems to act as a pro-inflammatory molecule modulating the production of NO induced by LPS. This proinflammatory effect of anandamide may be implicated in pathological reproductive events such as septic abortion. PMID:19490788

Vercelli, C A; Aisemberg, J; Billi, S; Cervini, M; Ribeiro, M L; Farina, M; Franchi, A M

2009-06-01

204

Suppressive effects of Indigofera suffruticosa Mill extracts on lipopolysaccharide-induced inflammatory responses in murine RAW 264.7 macrophages.  

PubMed

Indigofera suffruticosa Mill is used as an herbal medicine for the treatment of inflammation. The aim of this study is to assess the anti-inflammatory potency of I. suffruticosa and its likely molecular mechanisms of action in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. Both water and ethanolic extracts of I. suffruticosa significantly decreased LPS-induced nitric oxide (NO) as well as the expression of inducible nitric oxide synthase (iNOS), tumor necrosis factor-?, and pro-interleukin-1?. Moreover, LPS-induced inhibitory factor-?B-? phosphorylation, nuclear factor-?B (NF-?B) nuclear protein-DNA binding affinity, and NF-?B reporter gene activity were dramatically inhibited by I. suffruticosa extracts. Exogenous addition of I. suffruticosa significantly induced heme oxygenase-1 (HO-1) expression, and the presence of HO-1 small interfering RNA partly reversed the inhibitory effects of I. suffruticosa on LPS-induced NO production and iNOS expression. Furthermore, I. suffruticosa induced HO-1 expression may be through activation of the ERK/nuclear factor E2-related factor 2 pathway. Eight phenolic compounds were found in the I. suffruticosa extracts, but salicylic acid was the only one detected in the plasma of mice fed with I. suffruticosa extracts. In summary, I. suffruticosa have a strong anti-inflammatory property that diminishes pro-inflammatory mediator expressions by lessening LPS-induced NF-?B activation and inducing HO-1 expression in macrophages. PMID:23352929

Chen, Tzy-Yen; Sun, Hai-Lun; Yao, Hsien-Tsung; Lii, Chong-Kuei; Chen, Haw-Wen; Chen, Pei-Yin; Li, Chien-Chun; Liu, Kai-Li

2013-01-23

205

Altered Regulation of Renal Nitric Oxide and Atrial Natriuretic Peptide Systems in Lipopolysaccharide-induced Kidney Injury  

PubMed Central

Nitric oxide (NO) and atrial natriuretic peptide (ANP) may induce vascular relaxation by increasing the production of cyclic guanosine monophosphate (cGMP), an important mediator of vascular tone during sepsis. This study aimed to determine whether regulation of NO and the ANP system is altered in lipopolysaccharide (LPS)-induced kidney injury. LPS (10 mg.kg-1) was injected in the tail veins of male Sprague-Dawley rats; 12 hours later, the kidneys were removed. Protein expression of NO synthase (NOS) and neutral endopeptidase (NEP) was determined by semiquantitative immunoblotting. As an index of synthesis of NO, its stable metabolites (nitrite/nitrate, NOx) were measured using colorimetric assays. mRNA expression of the ANP system was determined by real-time polymerase chain reaction. To determine the activity of guanylyl cyclase (GC), the amount of cGMP generated in response to sodium nitroprusside (SNP) and ANP was calculated. Creatinine clearance decreased and fractional excretion of sodium increased in LPS-treated rats compared with the controls. Inducible NOS protein expression increased in LPS-treated rats, while that of endothelial NOS, neuronal NOS, and NEP remained unchanged. Additionally, urinary and plasma NOx levels increased in LPS-treated rats. SNP-stimulated GC activity remained unchanged in the glomerulus and papilla in the LPS-treated rats. mRNA expression of natriuretic peptide receptor (NPR)-C decreased in LPS-treated rats, while that of ANP and NPR-A did not change. ANP-stimulated GC activity reduced in the glomerulus and papilla. In conclusion, enhancement of the NO/cGMP pathway and decrease in ANP clearance were found play a role in the pathogenesis of LPS-induced kidney injury.

Bae, Eun Hui; Kim, In Jin; Ma, Seong Kwon; Lee, Jong Un

2011-01-01

206

Role of CB1 and CB2 receptors in the inhibitory effects of cannabinoids on lipopolysaccharide-induced nitric oxide release in astrocyte cultures.  

PubMed

The purpose of this study was to investigate the role of the central cannabinoid receptor (CB(1)) in mediating the actions of the endogenous cannabinoid agonist anandamide and the synthetic cannabinoid CP-55940. Activation of primary mouse astrocyte cultures by exposure to bacterial lipopolysaccharide (LPS) caused a marked (approximately tenfold) increase in nitric oxide (NO) release. Coincubation with the cannabinoid agonists anandamide or CP-55940 markedly inhibited release of NO (-12% to -55%). This effect was abolished by SR-141716A (1 microM), a CB1 receptor antagonist. SR-141716A alone also significantly increased NO release in response to LPS, suggesting that endogenous cannabinoids modify inflammatory responses. In contrast, coincubation with the CB2 receptor antagonist SR-144528 (1 microM) abolished the inhibitory effects of the endogenous cannabinoid anandamide on LPS-induced NO release, although this may reflect nonspecific effects of this ligand or cannabinoid actions through atypical receptors of anandamide. We also showed that endogenous or synthetic cannabinoids inhibit LPS-induced inducible NO synthase expression (mRNA and protein) in astrocyte cultures. These results indicate that CB1 receptors may promote antiinflammatory responses in astrocytes. PMID:11891798

Molina-Holgado, Francisco; Molina-Holgado, Eduardo; Guaza, Carmen; Rothwell, Nancy J

2002-03-15

207

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

208

Trail interacts redundantly with nitric oxide in rat astrocytes: Potential contribution to neurodegenerative processes  

Microsoft Academic Search

The proapoptotic cytokine TRAIL has been shown to enhance amyloid-?-dependent neurotoxicity. Here are reported interactions between TRAIL and nitric oxide (NO) in cultured rat astrocytes in vitro. Rat astrocytes expressed all TRAIL receptor mRNAs and proteins. However, TRAIL failed in inducing apoptosis of astrocytes, whereas these cells released substantial amounts of nitrites. A TRAIL-neutralizing antibody was able to prevent LPS-induced

Giuseppina Cantarella; Laurence Lempereur; Maria Antonia D'Alcamo; Nunziata Risuglia; Vera Cardile; Giuseppa Pennisi; Giovanna Maria Scoto; Renato Bernardini

2007-01-01

209

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

210

Bauer Ketones 23 and 24 from Echinacea paradoxa var. paradoxa Inhibit Lipopolysaccharide-induced Nitric Oxide, Prostaglandin E2 and Cytokines in RAW 264.7 Mouse Macrophages  

PubMed Central

Among the nine Echinacea species, E. purpurea, E. angustifolia and E. pallida, have been widely used to treat the common cold, flu and other infections. In our study, ethanol extracts of these three Echinacea species and E. paradoxa, including its typical variety, E. paradoxa var. paradoxa, were screened in lipopolysaccharide (LPS)-stimulated macrophage cells to assess potential anti-inflammatory activity. Echinacea paradoxa var. paradoxa, rich in polyenes/polyacetylenes, was an especially efficient inhibitor of LPS-induced production of nitric oxide (NO), prostaglandin E2 (PGE2), interleukin-1 beta (IL-1?) and interleukin-6 (IL-6) by 46%, 32%, 53% and 26%, respectively, when tested at 20 ?g/ml in comparison to DMSO control. By bioactivity-guided fractionation, pentadeca-8Z-ene-11, 13-diyn-2-one (Bauer ketones 23, compound 1) and pentadeca-8Z, 13Z-dien-11-yn-2-one (Bauer ketone 24, compound 2) from E. paradoxa var. paradoxa were found primarily responsible for inhibitory effects on NO and PGE2 production. Moreover, Bauer ketone 24 (compound 2) was the major contributor to inhibition of inflammatory cytokine production in LPS-induced mouse macrophage cells. These results provide a rationale for exploring the medicinal effects of the Bauer ketone-rich taxon, E. paradoxa var. paradoxa, and confirm the anti-inflammatory properties of Bauer ketones 23 and 24.

Zhang, Xiaozhu; Rizshsky, Ludmila; Hauck, Catherine; Qu, Luping; Widrlechner, Mark P.; Nikolau, Basil J.; Murphy, Patricia A.; Birt, Diane F.

2011-01-01

211

The Role of Chondroitin Sulfate Chains of Urinary Trypsin Inhibitor in Inhibition of LPS-Induced Increase of Cytosolic Free Ca 2+in HL60 Cells and HUVEC Cells  

Microsoft Academic Search

Preincubation of HL60 cells and HUVEC cells with urinary trypsin inhibitor (UTI) inhibited increase of cytosolic free Ca2+induced by LPS. In contrast, an increase of cytosolic free Ca2+induced by LPS was not inhibited by deglycosylated UTI, UTI treated with monoclonal antibody of chondroitin sulfate.45Ca2+binding showed that UTI binds45Ca2+dose-dependently. Scatchard plot analysis showed that UTI has two binding sites for Ca2+,

Naohiro Kanayama; Kayoko Maehara; Masako Suzuki; Yutaka Fujise; Toshihiko Terao

1997-01-01

212

Enhancement of antinociception by coadminstration of minocycline and a non-steroidal anti-inflammatory drug indomethacin in naďve mice and murine models of LPS-induced thermal hyperalgesia and monoarthritis  

Microsoft Academic Search

BACKGROUND: Minocycline and a non-steroidal anti-inflammatory drug (NSAID) indomethacin, have anti-inflammatory activities and are both used in the management of rheumatoid arthritis. However, there are no reports on whether coadministration of these drugs could potentiate each other's activities in alleviating pain and weight bearing deficits during arthritis. METHODS: LPS was injected to BALB\\/c mice intraperitoneally (i.p.) to induce thermal hyperalgesia.

Ala'a Ahmed Abu-Ghefreh; Willias Masocha

2010-01-01

213

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

2011-06-30

214

Microsatellite (GT)n polymorphism at 3'UTR of SLC11A1 influences the expression of brucella LPS induced MCP1 mRNA in buffalo peripheral blood mononuclear cells.  

PubMed

A (GT)n microsatellite polymorphism at 3'UTR of SLC11A1(solute carrier family 11A1) is associated with the natural resistance to bovine brucellosis. A pleiotropic effect of SLC11A1 on other candidate genes influencing the host resistance including monocyte chemotactic/chemoattractant protein 1 (MCP1) is also hypothesized. In the present study, we report the cloning and characterization of the complete coding sequence of bubaline (bu) MCP1 and its tissue distribution at the transcript level. The buMCP1 exhibited as high as 99% and >80% of sequence identities with the bovine and other domestic animal species homologues. The buMCP1 mRNA was abundant across the different tissues: most abundant in liver and mammary gland, moderate in ovary, skeletal muscle and testis, and least in uterus. Further, quantitative real-time PCR (RTqPCR) analysis revealed that PBMCs carrying so called resistant GT13 allele produced more MCP1 mRNA endogenously as well as when induced with brucella LPS suggesting the pleiotropic roles of SLC11A1 in conferring resistance against the intracellular pathogens particularly against brucellosis. However, the underlying molecular mechanisms by which 3'UTR SLC11A1 concomitantly increases the production of chemokines like MCP1 are yet to be investigated. PMID:23333195

Balasubramaniam, Sivamani; Kumar, Subodh; Sharma, Arjava; Mitra, Abhijit

2013-01-04

215

LPS-induced stimulation of phagocytosis in the sipunculan worm Themiste petricola: possible involvement of human CD14, CD11B and CD11C cross-reactive molecules.  

PubMed

Coelomocytes of Themiste petricola, a marine invertebrate of the phylum Sipuncula, were exposed in vitro to bacterial lipopolysaccharides (LPS), and the phagocytic activity against heat-killed yeast (Saccharomices cerevisiae) was evaluated using a flow cytometric assay. An increase of phagocytic activity was observed following pre-incubation of coelomocytes over 20 h with either 5 micrograms/mL LPS or 1.5 micrograms/mL phorbol 12-myristate 13-acetate (PMA). The phagocytic enhancement induced by LPS was blocked by co-incubation with polymixin B, a ligand for the lipid A region of LPS. In a 72 h stimulation assay, LPS was also found to enhance phagocytosis. The enhancement was significantly higher when coelomocytes were incubated with LPS plus coelomic plasma. Using mAbs directed against human CD14 and components of the human LFA-1 complex, we identified coelomocyte surface antigens cross-reactive with CD14, CD11b and CD11c. The expression of CD11b and CD11c antigens was augmented by LPS treatment of coelomocytes. By double fluorescence assays, using mAb Leu-M3 and fluorescein labeled yeast, phagocytic coelomocytes were found to be mainly anti-CD14 positive. No cross-reactions were detected with mAbs against CD11a and CD18. Enzymatic treatment of coelomocytes with phosphatidyl inositol phospholipase C (PI-PLC) reduced the expression of the CD14-like antigen. The presence, in sipunculan coelomocytes, of antigens cross-reactive with CD14, the alpha chain of CR3 and of p150,95 raises the possibility that molecules related, although not necessary homologous, to the mammalian counterparts may have a role in the defense systems of these animals. PMID:9303273

Blanco, G A; Escalada, A M; Alvarez, E; Hajos, S

216

Mechanism for Prenatal LPS-Induced DA Neuron Loss.  

National Technical Information Service (NTIS)

In nonfamilial Parkinson's Disease (PD) the etiologies of the majority of patients are still unknown. However, recent advances by the authors suggest that prenatal exposure to the bacterial toxin lipopolysaccharide (LPS) could be an important etiology for...

P. M. Carvey

2006-01-01

217

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

PubMed

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 microg ml-1), participated in this process. Fetal rat lung airway surface complexity rose 2.5-fold over 96h 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 TGFbeta suppresses iNOS activity, we determined if feedback regulation modulated NO-dependent maturation. LPS induced TGFbeta1 release and SMAD4 nuclear translocation 96 h after treatment. Treatment of explants with a blocking antibody against TGFbeta1 sustained NO production and airway morphogenesis whereas recombinant TGFbeta1 antagonized these effects. Feedback regulation of NO synthesis by TGFbeta may, thus, modulate airway branching and maturation of the fetal lung. PMID:16934757

Rae, C; Cherry, J I; Land, F M; Land, S C

2006-08-22

218

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

219

Catalepsy induced by nitric oxide synthase inhibitors  

Microsoft Academic Search

1.1. Previous study showed that NG-nitro-l-arginine (l-NOARG), an inhibitor of nitric oxide synthase, induces catalepsy in a dose-dependent manner in male albino-Swiss mice.2.2. The objective of the present work was to further investigate this effect, extending it to other NOS inhibitors.3.3. Results showed that l-NOARG (40–80 mg\\/kg IP), NG-nitro-l-arginine methylester (l-NAME, 40–160 mg\\/kg IP) or NG-monomethyl-l-arginine (l-NMMA, 80 mg\\/kg IP)

E. A. Del Bel; C. A. da Silva; F. S. Guimarăes

1998-01-01

220

Carnosic acid attenuates lipopolysaccharide-induced liver injury in rats via fortifying cellular antioxidant defense system.  

PubMed

The study investigated the protective effects of carnosic acid (CA), the principal constituent of rosemary, on lipopolysaccharide (LPS)-induced oxidative/nitrosative stress and hepatotoxicity in rats. CA was administered orally to rats at doses of 15, 30 and 60 mg/kg body weight before LPS challenge (single intraperitoneal injection, 1 mg/kg body weight). The results revealed that CA inhibited LPS-induced liver damage and disorder of lipid metabolism, which were mainly evidenced by decreased serum levels of alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase. CA also inhibited LPS-induced oxidative/nitrosative stress by decreasing lipid peroxidation, protein carbonylation, and serum levels of nitric oxide. Histopathological examination demonstrated that CA could improve pathological abnormalities and reduce the immigration of inflammatory cells in liver tissues with LPS challenge. Concurrently, CA potently inhibited the LPS-induced rise in serum levels of the pro-inflammatory cytokines tumor necrosis factor-? and interleukin-6. CA supplementation markedly enhanced the body's cellular antioxidant defense system by restoring the levels of superoxide dismutase, glutathione peroxidase, and glutathione in serum and liver after the LPS challenge. In conclusion, the present study suggests that CA successfully and dose dependently attenuates LPS-induced hepatotoxicity possibly by preventing cytotoxic effects of oxygen free radicals, NO and cytokines. PMID:23200889

Xiang, Qisen; Liu, Zhigang; Wang, Yutang; Xiao, Haifang; Wu, Wanqiang; Xiao, Chunxia; Liu, Xuebo

2012-11-28

221

Inhibition of inducible nitric oxide synthase by ?-lapachone in rat alveolar macrophages and aorta  

PubMed Central

?-Lapachone, a plant product, has been shown to be a novel inhibitor of DNA topoisomerase. In this study, we performed experiments to examine the effects of ?-lapachone on lipopolysaccharide (LPS)-induced inducible nitric oxide (NO) synthase (iNOS) in rat alveolar macrophages and aortic rings. In alveolar macrophages, incubation with LPS (10??g?ml?1) for various time intervals resulted in a significant increase in nitrite production and iNOS protein synthesis, that was inhibited by co-incubation with ?-lapachone (1–4.5??M) without any cytotoxic effects. However, addition of ?-lapachone after induction of NO synthase by LPS failed to affect the nitrite production. Treatment with LPS (10??g?ml?1) for 6?h resulted in significant expression of mRNA for iNOS which was significantly inhibited in the presence of ?-lapachone (3??M) in alveolar macrophages. In endothelium-intact rings of thoracic aorta, ?-lapachone (1 and 3??M) markedly inhibited the hypocontractility to phenylephrine in aortic rings treated with LPS (10??g?ml?1) for 4?h. When ?-lapachone was added 3?h after LPS into the medium, the contractions evoked by phenylephrine were not significantly different in the presence or absence of ?-lapachone. Treatment with LPS (10??g?ml?1) for 4?h resulted in a significant increase in iNOS protein synthesis which was inhibited in the presence of ?-lapachone (3??M), but did not affect the constitutive (endothelial and neuronal) NOS forms in aortic rings. These results indicate that ?-lapachone is capable of inhibiting expression and function of iNOS in rat alveolar macrophages and aortic rings. It is considered that ?-lapachone can be developed as a potential anti-inflammatory agent in the future.

Liu, Shing-Hwa; Tzeng, Huei-Ping; Kuo, Min-Liang; Lin-Shiau, Shoei-Yn

1999-01-01

222

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.

Sun, Aizhen; Nie, Shengjun; Xing, Da

2012-01-01

223

Chondrocyte apoptosis induced by nitric oxide.  

PubMed Central

Chondrocytes stimulated with IL-1 produce high levels of nitric oxide (NO), which inhibits proliferation induced by transforming growth factor-beta or serum. This study analyzes the role of NO and IL-1 in the induction of chondrocyte cell death. NO generated from sodium nitroprusside induced apoptosis in cultured chondrocytes as demonstrated by electron microscopy, 4',6-dianidino-2-phenylindole dihydrochloride staining, FACS analysis, and histochemical detection of DNA fragmentation. Similar results were obtained with two other NO donors, 3-morpholinosynonimide-hydrochloride and s-nitroso-N-acetyl-D-L-penicillamine. In contrast, oxygen radicals generated by hypoxanthine/xanthine oxidase caused necrosis but did not induce chondrocyte apoptosis. To analyze whether endogenously generated NO induces apoptosis, chondrocytes were stimulated with IL-1, but there was no evidence for apoptotic changes. Combinations of NO inducers such as IL-1, lipopolysaccharide, tumor necrosis factor, and interferon-gamma also failed to trigger apoptosis. IL-1-stimulated chondrocytes are known to produce oxygen radicals that react with NO to form products that can induce cell death in other systems. We thus tested IL-1 in combination with the oxygen radical scavengers N-acetyl cysteine, dimethyl sulfoxide, or 5,5'-dimetylpyrroline 1-oxide. Under these conditions IL-1 was able to induce apoptosis, which was inhibited in a dose-dependent manner by the NO synthase inhibitor N-monomethyl L-arginine. Conversely, endogenous oxygen radicals induced by inflammatory mediators caused necrosis under conditions in which the simultaneous production of NO was reduced. These results suggest that NO, but not oxygen radicals, is the primary inducer of apoptosis in human articular chondrocytes. Images Figure 1 Figure 2 Figure 4 Figure 7

Blanco, F. J.; Ochs, R. L.; Schwarz, H.; Lotz, M.

1995-01-01

224

A hypoxia-responsive element mediates a novel pathway of activation of the inducible nitric oxide synthase promoter.  

PubMed

Picolinic acid, a catabolite of L-tryptophan, activates the transcription of the inducible nitric oxide synthase gene (iNOS) in IFN-gamma-treated murine macrophages. We performed functional studies on the 5' flanking region of the iNOS gene linked to a CAT reporter gene to identify the cis-acting element(s) responsible for the activation of iNOS transcription by picolinic acid. Transient transfection assays showed that the full-length iNOS promoter in the murine macrophage cell line ANA-1 was activated by the synergistic interaction between IFN-gamma and picolinic acid. Deletion or mutation of the iNOS promoter region from -227 to -209, containing a sequence homology to a hypoxia-responsive enhancer (iNOS-HRE), decreased picolinic acid- but not LPS-induced CAT activity by more than 70%. Functional studies using a tk promoter-CAT reporter gene plasmid demonstrated that the iNOS-HRE was sufficient to confer inducibility by picolinic acid but not by IFN-gamma or LPS. Electrophoretic mobility shift assays confirmed that picolinic acid alone induced a specific binding activity to the iNOS-HRE. Furthermore, we found that the iNOS-HRE activity was inducible by hypoxia and that hypoxia in combination with IFN-gamma activated the iNOS promoter in transient transfection assays and induced iNOS transcription and mRNA expression. These data establish that the iNOS-HRE is a novel regulatory element of the iNOS promoter activity in murine macrophages and provide the first evidence that iNOS is a hypoxia-inducible gene. PMID:7500013

Melillo, G; Musso, T; Sica, A; Taylor, L S; Cox, G W; Varesio, L

1995-12-01

225

Suppression of inducible nitric oxide synthase expression and amelioration of lipopolysaccharide-induced liver injury by polyphenolic compounds in Eucalyptus globulus leaf extract  

Microsoft Academic Search

Eucalyptus leaf extract (ELE) is rich in hydrolyzable tannins. We examined the effects of ELE and its constituents on lipopolysaccharide (LPS)-induced liver injury in mice. Mice fed a diet supplemented with 1% ELE were intraperitoneally administered LPS. Six hours later, the serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were significantly lower in the ELE-supplemented mice than in the

Keiichiro Sugimoto; Sayaka Sakamoto; Kazuya Nakagawa; Shuichi Hayashi; Naoki Harada; Ryoichi Yamaji; Yoshihisa Nakano; Hiroshi Inui

2011-01-01

226

Epigallocatechin-3-gallate prevents systemic inflammation-induced memory deficiency and amyloidogenesis via its anti-neuroinflammatory properties.  

PubMed

Neuroinflammation has been known to play a critical role in the pathogenesis of Alzheimer's disease (AD) through amyloidogenesis. In a previous study, we found that systemic inflammation by intraperitoneal (ip) injection of lipopolysaccharide (LPS) induces neuroinflammation and triggers memory impairment. In this present study, we investigated the inhibitory effects of epigallocatechin-3-gallate (EGCG) on the systemic inflammation-induced neuroinflammation and amyloidogenesis as well as memory impairment. ICR mice were orally administered with EGCG (1.5 and 3 mg/kg) for 3 weeks, and then the mice were treated by ip injection of LPS (250 ?g/kg) for 7 days. We found that treatment of LPS induced memory-deficiency-like behavior and that EGCG treatment prevented LPS-induced memory impairment and apoptotic neuronal cell death. EGCG also suppressed LPS-induced increase of the amyloid beta-peptide level and the expression of the amyloid precursor protein (APP), ?-site APP cleaving enzyme 1 and its product C99. In addition, we found that EGCG prevented LPS-induced activation of astrocytes and elevation of cytokines including tumor necrosis factor-?, interleukin (IL)-1?, macrophage colony-stimulating factor, soluble intercellular adhesion molecule-1 and IL-16, and the increase of inflammatory proteins, such as inducible nitric oxide synthase and cyclooxygenase-2, which are known factors responsible for not only activation of astrocytes but also amyloidogenesis. In the cultured astrocytes, EGCG also inhibited LPS-induced cytokine release and amyloidogenesis. Thus, this study shows that EGCG prevents memory impairment as well as amyloidogenesis via inhibition of neuroinflammatory-related cytokines released from astrocytes and suggests that EGCG might be a useful intervention for neuroinflammation-associated AD. PMID:22959056

Lee, Young-Jung; Choi, Dong-Young; Yun, Yeo-Pyo; Han, Sang Bae; Oh, Ki-Wan; Hong, Jin Tae

2012-09-05

227

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

228

Involvement of nitric oxide in lipopolysaccharide induced anorexia  

Microsoft Academic Search

Treatment with the bacterial endotoxin lipopolysaccharide (LPS) is a commonly used model to induce disease-related anorexia. Following LPS treatment inducible nitric oxide synthase (iNOS) is expressed in the hypothalamic arcuate nucleus (ARC), where nitric oxide (NO) inhibits orexigenic neurons. Intracellular STAT signaling is triggered by inflammatory stimuli and has been linked to the transcriptional regulation of iNOS. We evaluated whether

Thomas Riediger; Caroline Cordani; Catarina Soares Potes; Thomas A. Lutz

2010-01-01

229

Role of Inducible Nitric Oxide Synthase-Derived Nitric Oxide in Silica-Induced Pulmonary Inflammation and Fibrosis  

Microsoft Academic Search

Inhalation of crystalline silica can produce lung inflammation and fibrosis. Inducible nitric oxide synthase (iNOS)-derived nitric oxide (NO) is believed to be involved in silica-induced lung disease. To investigate the role of iNOS-derived NO in this disease, the responses of iNOS knockout (KO) versus C57Bl\\/6J wild-type (WT) mice to silica were compared. Male mice (8–10 wk old, mean body weight

Patti C. Zeidler; Ann Hubbs; Lori Battelli; Vincent Castranova

2004-01-01

230

Antifibrotic Role of Inducible Nitric Oxide Synthase  

Microsoft Academic Search

Long-term treatment in rats with l-NAME, an isoform-non-specific inhibitor of nitric oxide synthase (NOS), leads to fibrosis of the heart and kidney, suggesting that nitric oxide (NO) may play a role in preventing tissue fibrosis. In this process, a likely target of NO is the quenching of reactive oxygen species (ROS) through peroxynitrite formation, and one possible source for this

M. G. Ferrini; D. Vernet; T. R. Magee; A. Shahed; A. Qian; J. Rajfer; N. F. Gonzalez-Cadavid

2002-01-01

231

Failure of L-NAME to cause inhibition of nitric oxide synthesis: Role of inducible nitric oxide synthase  

Microsoft Academic Search

We addressed the hypothesis that administration of nitric oxide synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME) does not result in a sustained suppression of nitric oxide (NO) synthesis, because of a compensatory expression of inducible nitric oxide synthase (iNOS). L-NAME was administered in the drinking water (0.1–1.0 mg\\/ml) for 7 days to guinea pigs and rats. Nitric oxide synthesis was assessed

M. J. S. Miller; J. H. Thompson; X. Liu; S. Eloby-Childress; H. Sadowska-Krowicka; X-Jing Zhang; D. A. Clark

1996-01-01

232

Rosmarinic acid in Prunella vulgaris ethanol extract inhibits lipopolysaccharide-induced prostaglandin E2 and nitric oxide in RAW 264.7 mouse macrophages.  

PubMed

Prunella vulgaris has been used therapeutically for inflammation-related conditions for centuries, but systematic studies of its anti-inflammatory activity are lacking and no specific active components have been identified. In this study, water and ethanol extracts of four P. vulgaris accessions were applied to RAW 264.7 mouse macrophages, and the ethanol extracts significantly inhibited lipopolysaccharide (LPS)-stimulated prostaglandin E2 (PGE2) and nitric oxide (NO) production at 30 microg/mL without affecting cell viability. Extracts from different accessions of P. vulgaris were screened for anti-inflammatory activity to identify accessions with the greatest activity. The inhibition of PGE2 and NO production by selected extracts was dose-dependent, with significant effects seen at concentrations as low as 10 microg/mL. Fractionation of ethanol extracts from the active accession, Ames 27664, suggested fractions 3 and 5 as possible major contributors to the overall activity. Rosmarinic acid (RA) content in P. vulgaris was found to independently inhibit inflammatory response, but it only partially explained the extracts' activity. LPS-induced cyclooxygenase-2 (COX-2) and nitric oxide synthase (iNOS) protein expression were both attenuated by P. vulgaris ethanol extracts, whereas RA inhibited only COX-2 expression. PMID:19919113

Huang, Nan; Hauck, Cathy; Yum, Man-Yu; Rizshsky, Ludmila; Widrlechner, Mark P; McCoy, Joe-Ann; Murphy, Patricia A; Dixon, Philip M; Nikolau, Basil J; Birt, Diane F

2009-11-25

233

Evaluation of natural products on inhibition of inducible cyclooxygenase (COX-2) and nitric oxide synthase (iNOS) in cultured mouse macrophage cells.  

PubMed

The inhibitors of prostaglandin biosynthesis and nitric oxide production have been considered as potential anti-inflammatory and cancer chemopreventive agents. In this study, we evaluated approximately 170 methanol extracts of natural products including Korean herbal medicines for the inhibition of prostaglandin E(2) production (for COX-2 inhibitors) and nitric oxide formation (for iNOS inhibitors) in lipopolysaccharide (LPS)-induced mouse macrophages RAW264.7 cells. As a result, several extracts such as Aristolochia debilis, Cinnamomum cassia, Cinnamomum loureirii, Curcuma zedoaria, Eugenia caryophyllata, Pterocarpus santalius, Rehmania glutinosa and Tribulus terrestris showed potent inhibition of COX-2 activity (>80% inhibition at the test concentration of 10 micro g/ml). In addition, the extracts of A. debilis, Caesalpinia sappan, Curcuma longa, C. zedoaria, Daphne genkwa and Morus alba were also considered as potential inhibitors of iNOS activity (>70% inhibition at the test concentration of 10 micro g/ml). These active extracts mediating COX-2 and iNOS inhibitory activities are warranted for further elucidation of active principles for development of new cancer chemopreventive and/or anti-inflammatory agents. PMID:12413723

Hong, Chae Hee; Hur, Sun Kyung; Oh, O-Jin; Kim, Sun Sook; Nam, Kyung Ae; Lee, Sang Kook

2002-11-01

234

Insulin inhibits inducible nitric oxide synthase in skeletal muscle cells  

Microsoft Academic Search

Summary   Recent studies have shown that cytokines and endotoxins impair insulin-stimulated glucose transport by activating the expression\\u000a of inducible nitric oxide synthase (iNOS) and nitric oxide (NO) production in skeletal muscle cells. In this study, we investigated\\u000a whether iNOS induction is modulated by insulin in L6 myocytes. Long term exposure of muscle cells to tumour necrosis factor-?\\u000a (TNF-?), interferon-? (IFN-?)

S. Bédard; B. Marcotte; A. Marette

1998-01-01

235

Ganoderma lucidum inhibits inducible nitric oxide synthase expression in macrophages  

Microsoft Academic Search

Nitric oxide (NO) is a principal mediator in many physiological and pathological processes. Overproduction of NO via the inducible nitric oxide synthase (iNOS) has cytotoxic effect through the formation of peroxynitrite with superoxide anion. The iNOS is mainly expressed in macrophages and is able to produce large amount of NO. The expression of iNOS is mainly regulated at the transcriptional

Connie W. H. Woo; Ricky Y. K. Man; Yaw L. Siow; Patrick C. Choy; Eric W. Y. Wan; Chak S. Lau; Karmin O

2005-01-01

236

Differential modulatory effects of Annexin 1 on nitric oxide synthase induction by lipopolysaccharide in macrophages  

PubMed Central

Annexin-1 (ANXA1) is a glucocorticoid-regulated protein that modulates the effects of bacterial lipopolysaccharide (LPS) on macrophages. Exogenous administration of peptides derived from the N-terminus of ANXA1 reduces LPS-stimulated inducible nitric oxide synthase (iNOS) expression, but the effects of altering the endogenous expression of this protein are unclear. We transfected RAW264.7 murine macrophage-like cell lines to over-express constitutively ANXA1 and investigated whether this protein modulates the induction of iNOS, cyclooxygenase-2 (COX-2) and tumour necrosis factor-? (TNF-?) in response to LPS. In contrast to exogenous administration of N-terminal peptides, endogenous over-expression of ANXA1 results in up-regulation of LPS-induced iNOS protein expression and activity. However, levels of iNOS mRNA are unchanged. ANXA1 has no effect on COX-2 or TNF-? production in response to LPS. In experiments to investigate the mechanisms underlying these phenomena we observed that activation of signalling proteins classically associated with iNOS transcription was unaffected. Over-expression of ANXA1 constitutively activates extracellular signal regulated kinase (ERK)-1 and ERK-2, components of a signalling pathway not previously recognized as regulating LPS-induced iNOS expression. Inhibition of ERK activity, by the inhibitor U0126, reduced LPS-induced iNOS expression in our cell lines. Over-expression of ANXA1 also modified LPS-induced phosphorylation of the ERK-regulated translational regulation factor eukaryotic initiation factor 4E. Our data suggest that ANXA1 may modify iNOS levels by post-transcriptional mechanisms. Thus differential effects on iNOS expression in macrophages are seen when comparing acute administration of ANXA1 peptides versus the chronic endogenous over-expression of ANXA1.

Smyth, Tomoko; Harris, Hayley J; Brown, Andrew; Totemeyer, Sabine; Farnfield, Belinda A; Maskell, Duncan J; Matsumoto, Makoto; Plevin, Robin; Alldridge, Louise C; Bryant, Clare E

2006-01-01

237

Endocannabinoid system and nitric oxide are involved in the deleterious effects of lipopolysaccharide on murine decidua.  

PubMed

Endocannabinoids are an important family of lipid-signaling molecules that are widely distributed in mammalian tissues and anandamide (AEA) was the first member identified. The uterus contains the highest concentrations of AEA yet discovered in mammalian tissues and this suggests that it might play a role in reproduction. Previous results from our laboratory have shown that AEA modulated NO synthesis in rat placenta. The production of small amounts of nitric oxide regulates various physiological reproductive processes such as implantation, decidualization and myometrial relaxation. But in an inflammatory setting such as sepsis, NO is produced in big amounts and has toxic effects as it is a free radical. The results presented in this study indicate that LPS-induced NO synthesis and tissue damage were mediated by AEA. Decidual LPS-induced NO production was abrogated either by co-incubation with CB1 (AM251) or CB2 (SR144528) antagonists which suggests that both receptors could be mediating this effect. On the other hand, LPS-induced tissue damage and this deleterious effect was partially abrogated by incubating tissue explants with LPS plus CB1 receptor antagonist. Our findings suggest that AEA, probably by increasing NO synthesis, participates in the deleterious effect of LPS in implantation sites. These effects could be involved in pathological reproductive events such as septic abortion. PMID:19428101

Vercelli, C A; Aisemberg, J; Billi, S; Wolfson, M L; Franchi, A M

2009-05-09

238

Inhibition of pro-inflammatory cytokines and inducible nitric oxide by extract of Emilia sonchifolia L. aerial parts.  

PubMed

Emilia sonchifolia L. (Asteraceae) is used in ethnomedicine for the treatment of a wide array of inflammatory disorders. This practice has also been supported by scientific reports which showed that extracts of E. sonchifolia possess anti-inflammatory effects in rodents. However, the mechanism(s) through which the extracts produce these effects is not known. In this study, the effect of a methanol/methylene chloride extract of E. sonchifolia (ES) on the levels of IL-1? and TNF-? after an intraperitoneal lipopolysaccharide (LPS; 1?mg/kg) challenge was investigated in mice. The effect of ES on TNF-? and inducible nitric oxide (iNO) production by LPS-stimulated bone marrow-derived macrophages (BMMDM) was also investigated in vitro. BMMDM were pre-incubated for 2?h with ES (20, and 100 ?g/mL) or with Pyrrolidine dithiocarbamate, PDTC (100 µM) and then activated with LPS, and then the IL-1?, TNF-? and NO production measured in the cell-free conditioned culture supernatant after 24?h of incubation. In groups of mice pre-treated with ES, the systemic levels of IL-1? and TNF-? induced by LPS were found to be significantly (p < 0.05) lower. In vitro, ES treatment caused a concentration-dependent decrease in LPS-inducible IL-1?, TNF-?, and NO production by BMDM compared to the effects of treatment of the cells with LPS alone without affecting the viability of the cells. The results of these studies suggest that treatment with ES alleviated inflammatory responses possibly through a suppression of pro-inflammatory mediators and cytokines such as IL-1?, TNF-?, and iNO. PMID:22712801

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

2012-06-20

239

Lipopolysaccharide-induced fever in Pekin ducks is mediated by prostaglandins and nitric oxide and modulated by adrenocortical hormones.  

PubMed

Information on avian fever is limited, and, in particular, very little is known about the mediators and modulators of the febrile response in birds. Therefore, in this study, the possible mediatory roles of nitric oxide (NO) and prostaglandins (PGs), together with a potential modulatory role for adrenocortical hormones in the generation of fever was investigated in conscious Pekin ducks. Their body temperatures were continuously measured by abdominally implanted temperature-sensitive data loggers. The febrile response induced by intramuscular injection of LPS at a dose of 100 microg/kg was compared with and without inhibition of NO production by N-nitro-L-arginine methyl ester (L-NAME), inhibition of PG synthesis (by diclofenac), and elevation of circulating concentrations of dexamethasone and corticosterone (by exogenous administration). LPS administration induced a marked, monophasic fever with a rise in temperature of more than 1 degrees C after 3-4 h. In the presence of L-NAME, diclofenac, and adrenocorticoids at doses that had no effect upon normal body temperature in afebrile ducks, there was a significant inhibition of the LPS-induced fever. In addition, during the febrile response, the blood concentration of corticosterone was significantly elevated (from a basal level of 73.6 +/- 9.8 ng/ml to a peak level of 132.6 +/- 16.5 ng/ml). The results strongly suggest that the synthesis of both NO and PGs is a vital step in the generation of fever in birds and that the magnitude of the response is subject to modulation by adrenocorticoids. PMID:16037125

Gray, David A; Maloney, Shane K; Kamerman, Peter R

2005-07-21

240

Melatonin inhibits visfatin-induced inducible nitric oxide synthase expression and nitric oxide production in macrophages.  

PubMed

Aberrant expression of inducible nitric oxide synthase (iNOS) in macrophages, which has been reported to be suppressed by melatonin, has an important contribution in the development of pathological inflammation. Visfatin, an adipokine, regulates the expression of various inflammatory factors, leading to inflammation; however, the influence of visfatin on iNOS-driven processes in macrophages is unclear. Here, we report the assessment of the role of visfatin in the regulation of iNOS gene expression in macrophages. Our data show that the levels of iNOS protein in peritoneal macrophages as well as nitric oxide (NO) in blood plasma were significantly lower after lipopolysaccharide treatment in visfatin(+/-) mice than those in the WT mice. In addition, visfatin increases iNOS mRNA and protein levels in RAW 264.7 cells, along with increasing production of NO. The enhancement of iNOS expression was prevented by treating the cells with inhibitors of the Janus kinase 2/signal transducers and activators of transcription 3 (JAK2/STAT3), nuclear factor (NF)-?B, extracellular signal-regulated kinase 1/2, and c-Jun N-terminal kinase pathways. Our results also show that visfatin-induced iNOS expression and NO production were significantly inhibited by melatonin, an effect that was closely associated with a reduction in phosphorylated JAK2/STAT3 levels and with the inhibition of p65 translocation into nucleus. In conclusion, our data show, for the first time, that melatonin suppresses visfatin-induced iNOS upregulation in macrophages by inhibiting the STAT3 and NF-?B pathways. Moreover, our data suggest that melatonin could be therapeutically useful for attenuating the development of visfatin-iNOS axis-associated diseases. PMID:23869429

Kang, Young-Soon; Kang, Yong-Gyu; Park, Hyun-Joo; Wee, Hee-Jun; Jang, Hye-Ock; Bae, Moon-Kyoung; Bae, Soo-Kyung

2013-07-22

241

Catecholamines?? Enhancement of Inducible Nitric Oxide Synthase-Induced Nitric Oxide Biosynthesis Involves CAT1 and CAT2A  

Microsoft Academic Search

Catecholamines enhance inducible nitric oxide syn- thase (iNOS) expression that results in nitric oxide (NO) overproduction in lipopolysaccharide (LPS)- stimulated macrophages. L-arginine transport medi- ated by cationic amino acid transporters (including CAT-1, CAT-2, CAT-2A, and CAT-2B) is crucial in regulating iNOS activity. We sought to assess the ef- fects of catecholamines on L-arginine transport and CATisozymeexpressioninstimulatedmacrophages. Confluent RAW264.7 cells were

Wen-Chou Lin; Pei-Shan Tsai; Chun-Jen Huang

2005-01-01

242

Inducible Nitric Oxide Synthase Mediates Bone Loss in Ovariectomized Mice  

Microsoft Academic Search

Several clinical studies have shown that bone loss may be attributed to osteoclast recruitment induced by mediators of inflammation. In different experimental paradigms we have recently demonstrated that estrogen exhibits antiinflamma- tory activity by preventing the induction of inducible nitric oxide synthase (iNOS) and other components of the inflam- matory reaction. To verify whether this could explain the estrogen-dependent blockade

SALVATORE CUZZOCREA; EMANUELA MAZZON; LAURA DUGO; TIZIANA GENOVESE; ROSANNA DI PAOLA; ZAIRA RUGGERI; ELISABETTA VEGETO; ACHILLE P. CAPUTI; DOMENICO PUZZOLO; ADRIANA MAGGI

2003-01-01

243

Soybean glyceollins mitigate inducible nitric oxide synthase and cyclooxygenase-2 expression levels via suppression of the NF-?B signaling pathway in RAW 264.7 cells.  

PubMed

Glyceollins, produced to induce disease resistance responses against specific species, such as an incompatible pathogen Phytophthora sojae in soybeans, have the potential to exhibit anti-inflammatory activity in RAW 264.7 cells. To investigate the anti-inflammatory effects of elicited glyceollins via a signaling pathway, we studied the glyceollin signaling pathway using several assays including RNA and protein expression levels. We found that soybean glyceollins significantly reduced LPS-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production, as well as the expression of inducible ?? synthase (iNOS) and cyclooxygenase-2 (COX-2) via the suppression of NF-?B activation. Glyceollins also inhibited the phosphorylation of I?B? kinase (IKK), the degradation of I?B?, and the formation of NF-?B-DNA binding complex in a dose-dependent manner. Furthermore, they inhibited pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-?, interleukin (IL)-1? and IL-18, but increased the generation of the anti-inflammatory cytokine IL-10. Collectively, the present data show that glyceollins elicit potential anti-inflammatory effects by suppressing the NF-?B signaling pathway in RAW 264.7 cells. PMID:22246209

Yoon, Eun-Kyung; Kim, Hyun-Kyoung; Cui, Song; Kim, Yong-Hoon; Lee, Sang-Han

2012-01-12

244

Suppressive effect of natural sesquiterpenoids on inducible cyclooxygenase (COX-2) and nitric oxide synthase (iNOS) activity in mouse macrophage cells.  

PubMed

Prostaglandins and nitric oxide produced by inducible cyclooygenase (COX-2) and nitric oxide synthase (iNOS), respectively, have been implicated as important mediators in the processes of inflammation and carcinogenesis. These potential COX-2 and iNOS inhibitors have been considered as antiinflammatory and cancer chemopreventive agents. In this study, we investigated the effect of natural sesquiterpenoids isolated from plants of the Zingiberaceae family on the activities of COX-2 and iNOS in cultured lipopolysaccharide (LPS)-activated mouse macrophage cell RAW 264.7 to discover new lead compounds as COX-2 or iNOS inhibitors. Xanthorrhizol, a sesquiterpenoid, isolated from the rhizome of Curcuma xanthorrhiza Roxb. (Zingiberaceae), exhibited a potent inhibition of COX-2 (IC50 = 0.2 microg/mL) and iNOS activity (IC50 = 1.0 microg/mL) in the assay system of prostaglandin E2 (PGE2) accumulation and nitric oxide production, respectively. Western blot analyses revealed that the inhibitory potential of xanthorrhizol on the COX-2 activity coincided well with the suppression of COX-2 protein expression in LPS-induced macrophages. In addition, sesquiterpenoids beta-turmerone and ar-turmerone isolated from the rhizome of Curcuma zedoaria Roscoe (Zingiberaceae) also showed a potent inhibitory activity of COX-2 (beta-turmerone, IC50 = 1.6 microg/mL; ar-turmerone, IC50 = 5.2 microg/mL) and iNOS (beta-turmerone, IC50 = 4.6 microg/mL; ar-turmerone, IC50 = 3.2 microg/mL). These results suggest that natural sesquiterpenoids from C. xanthorrhiza and C. zedoaria might be lead candidates for further developing COX-2 or iNOS inhibitors possessing cancer chemopreventive or anti-inflammatory properties. PMID:12086400

Lee, Sang Kook; Hong, Chai-Hee; Huh, Sun-Kyung; Kim, Sun-Sook; Oh, O-Jin; Min, Hye-Young; Park, Kwang-Kyun; Chung, Won-Yoon; Hwang, Jae-Kwan

2002-01-01

245

Ethanol extract of Magnolia officinalis prevents lipopolysaccharide-induced memory deficiency via its antineuroinflammatory and antiamyloidogenic effects.  

PubMed

Magnolia bark contains several compounds such as magnolol, honokiol, 4-O-methylhonokiol, obovatol, and other neolignan compounds. These compounds have been reported to have various beneficial effects in various diseases. There is sufficient possibility that ethanol extract of Magnolia officinalis is more effective in amyloidogenesis via synergism of these ingredients. Neuroinflammation has been known to play a critical role in the pathogenesis of Alzheimer's disease (AD). We investigated whether the ethanol extract of M.?officinalis (10?mg/?kg in 0.05% ethanol) prevents memory dysfunction and amyloidogenesis in AD mouse model by intraperitoneal lipopolysaccharide (LPS, 250?µg/?kg/day for seven times) injection. We found that ethanol extract of M.?officinalis prevented LPS-induced memory deficiency as well as inhibited the LPS-induced elevation of inflammatory proteins, such as inducible nitric oxide synthase and cyclooxygenase 2, and activation of astrocytes and microglia. In particular, administration of M.?officinalis ethanol extract inhibited LPS-induced amyloidogenesis, which resulted in the inhibition of amyloid precursor protein, beta-site amyloid-precursor-protein-cleaving enzyme 1 and C99. Thus, this study shows that ethanol extract of M.?officinalis prevents LPS-induced memory impairment as well as amyloidogenesis via inhibition of neuroinflammation and suggests that ethanol extract of M.?officinalis might be a useful intervention for neuroinflammation-associated diseases such as AD. PMID:22628265

Lee, Young-Jung; Choi, Dong-Young; Yun, Yeo-Pyo; Han, Sang Bae; Kim, Hwan Mook; Lee, Kiho; Choi, Seok Hwa; Yang, Mhan-Pyo; Jeon, Hyun Soo; Jeong, Jea-Hwang; Oh, Ki-Wan; Hong, Jin Tae

2012-05-25

246

Arginase Activity Mediates Retinal Inflammation in Endotoxin-Induced Uveitis  

PubMed Central

Arginase has been reported to reduce nitric oxide bioavailability in cardiovascular disease. However, its specific role in retinopathy has not been studied. In this study, we assessed the role of arginase in a mouse model of endotoxin-induced uveitis induced by lipopolysaccharide (LPS) treatment. Measurement of arginase expression and activity in the retina revealed a significant increase in arginase activity that was associated with increases in both mRNA and protein levels of arginase (Arg)1 but not Arg2. Immunofluorescence and flow cytometry confirmed this increase in Arg1, which was localized to glia and microglia. Arg1 expression and activity were also increased in cultured Muller cells and microglia treated with LPS. To test whether arginase has a role in the development of retinal inflammation, experiments were performed in mice deficient in one copy of the Arg1 gene and both copies of the Arg2 gene or in mice treated with a selective arginase inhibitor. These studies showed that LPS-induced increases in inflammatory protein production, leukostasis, retinal damage, signs of anterior uveitis, and uncoupling of nitric oxide synthase were blocked by either knockdown or inhibition of arginase. Furthermore, the LPS-induced increase in Arg1 expression was abrogated by blocking NADPH oxidase. In conclusion, these studies suggest that LPS-induced retinal inflammation in endotoxin-induced uveitis is mediated by NADPH oxidase-dependent increases in arginase activity.

Zhang, Wenbo; Baban, Babak; Rojas, Modesto; Tofigh, Sohrab; Virmani, Suvika K.; Patel, Chintan; Behzadian, M. Ali; Romero, Maritza J.; Caldwell, Robert W.; Caldwell, Ruth B.

2009-01-01

247

Nitric oxide-induced calcium release: activation of type 1 ryanodine receptor by endogenous nitric oxide.  

PubMed

Ryanodine receptors (RyRs), located in the sarcoplasmic/endoplasmic reticulum (SR/ER) membrane, are required for intracellular Ca2+ release that is involved in a wide range of cellular functions. In addition to Ca2+-induced Ca2+ release in cardiac cells and voltage-induced Ca2+ release in skeletal muscle cells, we recently identified another mode of intracellular Ca2+ mobilization mediated by RyR, i.e., nitric oxide-induced Ca2+ release (NICR), in cerebellar Purkinje cells. NICR is evoked by neuronal activity, is dependent on S-nitrosylation of type 1 RyR (RyR1) and is involved in the induction of long-term potentiation (LTP) of cerebellar synapses. In this addendum, we examined whether peroxynitrite, which is produced by the reaction of nitric oxide with superoxide, may also have an effect on the Ca2+ release via RyR1 and the cerebellar LTP. We found that scavengers of peroxynitrite have no significant effect either on the Ca2+ release via RyR1 or on the cerebellar LTP. We also found that an application of a high concentration of peroxynitrite does not reproduce neuronal activity-dependent Ca2+ release in Purkinje cells. These results support that NICR is induced by endogenous nitric oxide produced by neuronal activity through S-nitrosylation of RyR1. PMID:23247505

Kakizawa, Sho; Yamazawa, Toshiko; Iino, Masamitsu

2012-12-17

248

Salt-induced hemodynamic regulation mediated by nitric oxide.  

PubMed

Excess daily salt intake impairs vasodilatation and enhances vasoconstriction, resulting in reduction of regional blood flow and elevation of blood pressure in healthy individuals and hypertensive patients with either salt sensitivity or not tested for salt sensitivity or not evaluated for salt sensitivity. The mechanism may involve decreased production of nitric oxide via endothelial nitric oxide synthase (eNOS), impaired bioavailability of nitric oxide, and elevated plasma levels of asymmetric dimethylarginine (ADMA). Experimental animals, irrespective of salt sensitivity, although less extensive in those with salt-resistance, fed a high-salt diet have deteriorated endothelial functions; the mechanisms involved include an impairment of eNOS activation, a decrease in eNOS expression, and an increase in oxidative stress and ADMA. The imbalance of interactions between nitric oxide and angiotensin II is also involved in salt sensitivity. Deficiency of nitric oxide formed via neuronal NOS and inducible NOS may contribute to salt-induced hypertension. Reduced daily salt intake, therefore, would be the most rational prophylactic measure against the development of hypertension. PMID:21150639

Toda, Noboru; Arakawa, Kikuo

2011-03-01

249

Detection of nitric oxide production in mice by spin-trapping electron paramagnetic resonance spectroscopy  

Microsoft Academic Search

We describe here a spin-trapping method combined with X-band electron paramagnetic resonance (EPR) spectroscopy for ex vivo measurement of nitric oxide (·NO) levels in the urine of both normal and lipopolysaccharide (LPS)-induced shock mice. Normal or LPS-treated mice were injected subcutaneously with a metal-chelator complex, N-methyl-d-glucamine dithiocarbamate-ferrous iron, [(MGD)2\\/Fe], which binds to ·NO and forms a water-soluble [(MGD)2\\/Fe-NO] complex. At

Andrei M. Komarov; Ching-San Lai

1995-01-01

250

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.

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

251

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

252

Inducible nitric oxide synthase expression in human cerebral infarcts  

Microsoft Academic Search

The inducible or “immunological” isoform of nitric oxide synthase (iNOS) is induced in many cell types by inflammatory stimuli\\u000a and synthesizes toxic amounts of NO. In rodent models of focal cerebral ischemia, iNOS is expressed in neutrophils invading\\u000a the injured brain and in local blood vessels. Studies with iNOS inhibitors and iNOS null mice indicate that NO produced by\\u000a iNOS

Colleen Forster; H. Brent Clark; M. Elizabeth Ross; Constantino Iadecola

1999-01-01

253

Subtilase Cytotoxin Enhances Escherichia coli Survival in Macrophages by Suppression of Nitric Oxide Production through the Inhibition of NF-?B Activation  

PubMed Central

Subtilase cytotoxin (SubAB), which is produced by certain strains of Shiga-toxigenic Escherichia coli (STEC), cleaves an endoplasmic reticulum (ER) chaperone, BiP/Grp78, leading to induction of ER stress and caspase-dependent apoptosis. SubAB alters the innate immune response. SubAB pretreatment of macrophages inhibited lipopolysaccharide (LPS)-induced production of both monocyte chemoattractant protein 1 (MCP-1) and tumor necrosis factor ? (TNF-?). We investigated here the mechanism by which SubAB inhibits nitric oxide (NO) production by mouse macrophages. SubAB suppressed LPS-induced NO production through inhibition of inducible NO synthase (iNOS) mRNA and protein expression. Further, SubAB inhibited LPS-induced I?B-? phosphorylation and nuclear localization of the nuclear factor-?B (NF-?B) p65/p50 heterodimer. Reporter gene and chromatin immunoprecipitation (ChIP) assays revealed that SubAB reduced LPS-induced NF-?B p65/p50 heterodimer binding to an NF-?B binding site on the iNOS promoter. In contrast to the native toxin, a catalytically inactivated SubAB mutant slightly enhanced LPS-induced iNOS expression and binding of NF-?B subunits to the iNOS promoter. The SubAB effect on LPS-induced iNOS expression was significantly reduced in macrophages from NF-?B1 (p50)-deficient mice, which lacked a DNA-binding subunit of the p65/p50 heterodimer, suggesting that p50 was involved in SubAB-mediated inhibition of iNOS expression. Treatment of macrophages with an NOS inhibitor or expression of SubAB by E. coli increased E. coli survival in macrophages, suggesting that NO generated by macrophages resulted in efficient killing of the bacteria and SubAB contributed to E. coli survival in macrophages. Thus, we hypothesize that SubAB might represent a novel bacterial strategy to circumvent host defense during STEC infection.

Tsutsuki, Hiroyasu; Suzuki, Kotaro; Suto, Akira; Ogura, Kohei; Nagasawa, Sayaka; Ihara, Hideshi; Shimizu, Takeshi; Nakajima, Hiroshi; Moss, Joel; Noda, Masatoshi

2012-01-01

254

A novel antioxidant, octyl caffeate, suppression of LPS\\/IFN-?-induced inducible nitric oxide synthase gene expression in rat aortic smooth muscle cells  

Microsoft Academic Search

In the present study, we investigated the effects and mechanisms of a novel potent antioxidant, octyl caffeate, on the induction of iNOS expression by lipopolysaccharide (LPS) and interferon-? (IFN-?) in cultured primary rat aortic smooth muscle cells (RASMCs) in vitro and LPS-induced hypotension in vivo. Octyl caffeate (0.1–1.0?M) exerted a concentration-dependent inhibition of iron-catalyzed lipid peroxidation in rat brain homogenates.

George Hsiao; Ming-Yi Shen; Wen-Chiung Chang; Yu-Wen Cheng; Shiow-Lin Pan; Yueh-Hsiung Kuo; Tzeng-Fu Chen; Joen-Rong Sheu

2003-01-01

255

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.

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

2012-01-01

256

Hydrogen sulfide attenuates lipopolysaccharide-induced inflammation by inhibition of p38 mitogen-activated protein kinase in microglia  

Microsoft Academic Search

The present study attempts to investigate the effect of H2 So n lipopolysaccharide (LPS)-induced inflammation in both pri- mary cultured microglia and immortalized murine BV-2 microglial cells. We found that exogenous application of sodium hydrosulfide (NaHS) (a H2S donor, 10-300 lmol\\/L) attenu- ated LPS-stimulated nitric oxide (NO) in a concentration- dependent manner. Stimulating endogenous H2S production decreased LPS-stimulated NO production,

Li-Fang Hu; Peter T.-H. Wong; Philip K. Moore; Jin-Song Bian

2007-01-01

257

Aldose reductase regulates TNF-?-induced inducible nitric oxide synthase expression in human mesangial cells  

Microsoft Academic Search

Glomerulonephritis is one of the most important causes of renal failure, which is accompanied with production of Nitric Oxide\\u000a (NO) synthesized by inducible nitric oxide synthase (iNOS). Aldose reductase (AR) is the key enzyme in polyol pathway and\\u000a plays an important role in glucose metabolism. Here, we report our finding that AR regulates tumor-necrosis-factor-?-induced\\u000a (TNF-?-induced) iNOS expression in human mesangial

Jingjing ZhaoTao; Tao Jiang; Hui Li; Yuejuan Zhang; Nong Zhang

258

Rapid up-regulation of endothelial nitric-oxide synthase in a mouse model of Escherichia coli lipopolysaccharide-induced bladder inflammation.  

PubMed

Increases in the signaling molecule nitric oxide (NO) during inflammation may be linked not only to inducible nitric-oxide synthase (iNOS) but also to endothelial (e)NOS. Escherichia coli lipopolysaccharide (LPS) induces an inflammatory response in the bladder and rapidly increases phosphorylation of Akt/protein kinase B (Akt), a key enzyme regulating proliferation, apoptosis, and inflammation. Activated Akt phosphorylates human eNOS at serine 1177 and subsequently increases NOS activity. Because Akt and eNOS are both localized in the bladder urothelium, phosphorylation of eNOS by Akt provides an attractive mechanism for rapid increases in urinary NO production. Female mice were intraperitoneally injected with LPS (25 mg/kg) or pyrogen-free water (control). Four hours before LPS injection, some mice were injected with wortmannin, which inhibits Akt phosphorylation. Levels of urinary cyclic GMP, a downstream product of NO, increase 75% within 1 h after intraperitoneal injection of LPS, and this increase is blocked by wortmannin. Bladder eNOS and phosphorylated eNOS protein increase 94 and 151%, respectively, 1 h after LPS treatment, whereas iNOS was not detected. Wortmannin decreases eNOS phosphorylation by 60%. Furthermore, bladder Ca(2+)-dependent NOS activity (eNOS, neuronal NOS) is increased 79 +/- 20% 1 h after LPS treatment, whereas there is no increase in Ca(2+)-independent (iNOS) activity (n = 4). Increases in urinary cyclic GMP, NOS activity, and eNOS protein and phosphorylation 1 h after induction of inflammation with LPS, indicate that eNOS plays a role in the early response to bladder inflammation. PMID:15082754

Kang, Walter S; Tamarkin, Frank J; Wheeler, Marcia A; Weiss, Robert M

2004-04-13

259

Nitric Oxide-Donor SNAP Induces Xenopus Eggs Activation  

PubMed Central

Nitric oxide (NO) is identified as a signaling molecule involved in many cellular or physiological functions including meiotic maturation and parthenogenetic activation of mammalian oocytes. We observed that nitric oxide donor SNAP was potent to induce parthenogenetic activation in Xenopus eggs. NO-scavenger CPTIO impaired the effects of SNAP, providing evidence for the effects of the latter to be specific upon NO release. In Xenopus eggs, SNAP treatment induced pigment rearrangement, pronucleus formation and exocytosis of cortical granules. At a biochemical level, SNAP exposure lead to MAPK and Rsk inactivation within 30 minutes whereas MPF remained active, in contrast to calcium ionophore control where MPF activity dropped rapidly. MAPK inactivation could be correlated to pronuclear envelope reformation observed. In SNAP-treated eggs, a strong increase in intracellular calcium level was observed. NO effects were impaired in calcium-free or calcium limited medium, suggesting that that parthenogenetic activation of Xenopus oocytes with a NO donor was mainly calcium-dependent.

Jeseta, Michal; Marin, Matthieu; Tichovska, Hana; Melicharova, Petra; Cailliau-Maggio, Katia; Martoriati, Alain; Lescuyer-Rousseau, Arlette; Beaujois, Remy; Petr, Jaroslav; Sedmikova, Marketa; Bodart, Jean-Francois

2012-01-01

260

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

261

TXNIP Deficiency Exacerbates Endotoxic Shock via the Induction of Excessive Nitric Oxide Synthesis  

PubMed Central

Thioredoxin-interacting protein (TXNIP) has multiple functions, including tumor suppression and involvement in cell proliferation and apoptosis. However, its role in the inflammatory process remains unclear. In this report, we demonstrate that Txnip?/? mice are significantly more susceptible to lipopolysaccharide (LPS)-induced endotoxic shock. In response to LPS, Txnip?/? macrophages produced significantly higher levels of nitric oxide (NO) and inducible nitric oxide synthase (iNOS), and an iNOS inhibitor rescued Txnip?/? mice from endotoxic shock-induced death, demonstrating that NO is a major factor in TXNIP-mediated endotoxic shock. This susceptibility phenotype of Txnip?/? mice occurred despite reduced IL-1? secretion due to increased S-nitrosylation of NLRP3 compared to wild-type controls. Taken together, these data demonstrate that TXNIP is a novel molecule that links NO synthesis and NLRP3 inflammasome activation during endotoxic shock.

Suh, Hyun-Woo; Kim, Dong Oh; Park, Jeong-Ran; Jung, Haiyoung; Kim, Tae-Don; Yoon, Suk Ran; Min, Jeong-Ki; Na, Hee-Jun; Lee, Seon-Jin; Lee, Hee Gu; Lee, Young Ho; Lee, Hee-Bong; Choi, Inpyo

2013-01-01

262

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

PubMed

Inula britannica is a traditional medicinal plant used to treat bronchitis, digestive disorders, and inflammation in Eastern Asia. Here, we identified eupatolide, a sesquiterpene lactone from I. britannica, as an inhibitor of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression. Eupatolide inhibited the production of nitric oxide (NO) and prostaglandin E(2) (PGE(2)) as well as iNOS and COX-2 protein expression in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Eupatolide dose-dependently decreased the mRNA levels and the promoter activities of COX-2 and iNOS in LPS-stimulated RAW264.7 cells. Moreover, eupatolide significantly suppressed the LPS-induced expression of nuclear factor-kappa B (NF-kappaB) and activator protein-1 (AP-1) reporter genes. Pretreatment of eupatolide inhibited LPS-induced phosphorylation and degradation of I kappaB alpha, and phosphorylation of RelA/p65 on Ser-536 as well as the activation of mitogen-activated protein kinases (MAPKs) and Akt in LPS-stimulated RAW264.7 cells. Eupatolide induced proteasomal degradation of tumor necrosis factor receptor-associated factor-6 (TRAF6), and subsequently inhibited LPS-induced TRAF6 polyubiquitination. These results suggest that eupatolide blocks LPS-induced COX-2 and iNOS expression at the transcriptional level through inhibiting the signaling pathways such as NF-kappaB and MAPKs via proteasomal degradation of TRAF6. Taken together, eupatolide may be a novel anti-inflammatory agent that induces proteasomal degradation of TRAF6, and a valuable compound for modulating inflammatory conditions. PMID:20353767

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

2010-03-28

263

Nonsteroidal Anti-inflammatory Drugs Inhibit Expression of the Inducible Nitric Oxide Synthase Gene  

Microsoft Academic Search

Increased nitric oxide production is associated with acute and chronic inflammatory processes. Accordingly, we tested the hypothesis that the therapeutic action of nonsteroidal anti-inflammatory drugs could be attributed at least in part to inhibition of excess nitric oxide production. We report here that sodium salicylate, aspirin, ibuprofen, and indomethacin markedly inhibited the appearance of the inducible inflammatory nitric oxide synthase

E. E. Aeberhard; S. A. Henderson; N. S. Arabolos; J. M. Griscavage; F. E. Castro; C. T. Barrett; L. J. Ignarro

1995-01-01

264

Nitric oxide induces acrosome reaction in cryopreserved bovine spermatozoa.  

PubMed

The aim of this work was to study the effect of nitric oxide on acrosome reaction (AR) and the participation of protein kinases and reactive oxygen species in the AR of cryopreserved bovine spermatozoa. Spermatozoa were capacitated in Tyrode's albumin lactate pyruvate medium with heparin (10 IU ml(-1)) and then incubated with different concentrations of sodium nitroprusside (SNP) (1-200 micromol l(-1)). Methylene blue and haemoglobin were used to confirm the role of nitric oxide as an inducer of the AR. The participation of protein kinase A (PKA) , protein kinase C (PKC) and protein tyrosine kinase was evaluated using specific inhibitors of these enzymes (H-89, 50 micromol l(-1); bisindolylmaleimide I, 0.1 micromol l(-1) and genistein, 3 micromol l(-1)). The role of hydrogen peroxide or superoxide anion was evaluated by incubation with catalase or superoxide dismutase respectively. AR percentages were determined by the fluorescence technique with chlortetracycline. The highest levels of AR were obtained in capacitated spermatozoa treated with 5-200 micromol l(-1) SNP (24.8 +/- 1.8%). The presence of PKA, PKC and protein tyrosine kinase inhibitors likewise decreased AR percentages. The addition of superoxide dismutase had no effect on the AR level but catalase completely blocked it. These results indicate that nitric oxide induces AR in capacitated spermatozoa involving hydrogen peroxide and the participation of PKA, PKC and protein tyrosine kinase as part of the signal transduction mechanism which lead to the AR in cryopreserved bovine spermatozoa. PMID:16266394

Rodriguez, P C; O'Flaherty, C M; Beconi, M T; Beorlegui, N B

2005-10-01

265

Cross-Talk between Inducible Nitric Oxide Synthase and Cyclooxygenase in Helicobacter-pylori-Induced Gastritis  

Microsoft Academic Search

Objectives: The present study examined the cross-talk between prostanoids and nitric oxide (NO) in human gastric biopsies during Helicobacter pylori infection. Subjects and Methods: A pool of 1 or 2 biopsies per patient (11 H. pylori positive and 9 H. pylori negative) were incubated in the medium with\\/without drugs, 1400W and NS-398, inhibitors of inducible nitric oxide synthase (iNOS) and

L. Franco; G. Talamini

2009-01-01

266

Role of SelS in lipopolysaccharide-induced inflammatory response in hepatoma HepG2 cells.  

PubMed

To investigate the role of SelS in bacterial lipopolysaccharide (LPS) induced inflammatory response, some parameters in LPS-stimulated HepG2 cells were comparatively studied fore-and-aft SelS silence. LPS induced the decreases of cytoplasmic glutathione peroxidase (GPx-1) mRNA expression and activity, and the increases of reactive oxygen species (ROS) level, intracellular and extracellular nitric oxide (NO) levels, inducible nitric oxide synthase (iNOS) mRNA expression and activity, and serum amyloid A1 (SAA1) mRNA expression and secreted protein level in hepatoma HepG2 cells. When SelS was suppressed by small interfering RNA (siRNA), those decreases and increases were further aggravated under LPS stimulation, respectively. In conclusion, the negative association between SelS and the LPS-induced production of ROS, NO and SAA1 demonstrated that SelS had an important role in influencing inflammatory response, and that role may be related with SelS as a central component of retro-translocation channel in endoplasmic reticulum-associated protein degradation (ERAD) and its anti-oxidative property. PMID:18675776

Zeng, Jinhong; Du, Shaoqing; Zhou, Jun; Huang, Kaixun

2008-07-24

267

Cannabidiol reduces lipopolysaccharide-induced vascular changes and inflammation in the mouse brain: an intravital microscopy study  

PubMed Central

Background The phytocannabinoid cannabidiol (CBD) exhibits antioxidant and antiinflammatory properties. The present study was designed to explore its effects in a mouse model of sepsis-related encephalitis by intravenous administration of lipopolysaccharide (LPS). Methods Vascular responses of pial vessels were analyzed by intravital microscopy and inflammatory parameters measured by qRT-PCR. Results CBD prevented LPS-induced arteriolar and venular vasodilation as well as leukocyte margination. In addition, CBD abolished LPS-induced increases in tumor necrosis factor-alpha and cyclooxygenase-2 expression as measured by quantitative real time PCR. The expression of the inducible-nitric oxide synthase was also reduced by CBD. Finally, preservation of Blood Brain Barrier integrity was also associated to the treatment with CBD. Conclusions These data highlight the antiinflammatory and vascular-stabilizing effects of CBD in endotoxic shock and suggest a possible beneficial effect of this natural cannabinoid.

2011-01-01

268

Portal hypertension triggers local activation of inducible nitric oxide synthase gene in colonic mucosa.  

PubMed

Recently a new clinical entity "portal hypertensive colopathy" has been reported. It involves vascular abnormalities and bleeding. Because nitric oxide may mediate these changes, we studied whether portal hypertension affects nitric oxide synthase in portal hypertensive colonic mucosa. In portal hypertensive and sham-operated rats the following studies were done: (1) colonic mucosal blood flow, (2) quantitative histologic examination, (3) reverse transcription-polymerase chain reaction for nitric oxide synthase mRNA, (4) nitric oxide synthase activity assay, and (5) immunostaining for nitric oxide synthase. In portal hypertensive rats, colonic mucosal blood flow and the number of submucosal veins were significantly increased in comparison to sham-operated rats. The mRNA expression and enzyme activity for inducible nitric oxide synthase (but not constitutive nitric oxide synthase) were significantly increased in portal hypertensive rats. Fluorescence signal intensity for inducible nitric oxide synthase in endothelia of mucosal and submucosal veins was significantly higher in portal hypertensive rats than in sham-operated rats. Portal hypertension activates inducible nitric oxide synthase gene and protein in colonic mucosal vessels. The excess of nitric oxide generated by overexpressed inducible nitric oxide synthase may play an important role in the development of vascular and hemodynamic abnormalities characterizing portal hypertensive colopathy. PMID:9834352

Ohta, M; Kaviani, A; Tarnawski, A S; Itani, R; Sugimachi, K; Sarfeh, I J

269

Endostatin induces acute endothelial nitric oxide and prostacyclin release  

SciTech Connect

Chronic exposure to endostatin (ES) blocks endothelial cell (EC) proliferation, and migration and induces EC apoptosis thereby inhibiting angiogenesis. Nitric oxide (NO) and prostacyclin (PGI{sub 2}), in contrast, play important roles in promoting angiogenesis. In this study, we examined the acute effects of ES on endothelial NO and PGI{sub 2} production. Unexpectedly, a cGMP reporter cell assay showed that ES-induced acute endothelial NO release in cultured bovine aortic endothelial cells (BAECs). Enzyme immunoassay showed that ES also induced an acute increase in PGI{sub 2} production in BAECs. These results were confirmed by ex vivo vascular ring studies that showed vascular relaxation in response to ES. Immunoblot analysis showed that ES stimulated acute phosphorylation of endothelial nitric oxide synthase (eNOS) at Ser116, Ser617, Ser635, and Ser1179, and dephosphorylation at Thr497 in BAECs, events associated with eNOS activation. Short-term exposure of EC to ES, therefore, unlike long-term exposure which is anti-angiogenic, may be pro-angiogenic.

Li Chunying [Vascular Biology Center, Medical College of Georgia, Augusta, GA 30912 (United States); Harris, M. Brennan [Vascular Biology Center, Medical College of Georgia, Augusta, GA 30912 (United States); Department of Pediatrics, Medical College of Georgia, Augusta, GA 30912 (United States); Venema, Virginia J. [Vascular Biology Center, Medical College of Georgia, Augusta, GA 30912 (United States); Venema, Richard C. [Vascular Biology Center, Medical College of Georgia, Augusta, GA 30912 (United States) and Department of Pediatrics, Medical College of Georgia, Augusta, GA 30912 (United States) and Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta, GA 30912 (United States)]. E-mail: rvenema@mcg.edu

2005-04-15

270

Inhibitors from the rhizomes of Alpinia officinarum on production of nitric oxide in lipopolysaccharide-activated macrophages and the structural requirements of diarylheptanoids for the activity  

Microsoft Academic Search

The 80% aqueous acetone extract from the rhizomes of Alpinia officinarum, a Chinese medicinal herb, were found to inhibit nitric oxide (NO) production in lipopolysaccharide (LPS)-activated mouse peritoneal macrophages. Through bioassay-guided separation, two diarylheptanoids [7-(4?-hydroxy-3?-methoxyphenyl-1-phenylhept-4-en-3-one and 3,5-dihydroxy-1,7-diphenylheptane] and a flavonol constituent (galangin) substantially inhibited LPS-induced NO production with IC50 values of 33–62?M. To clarify structure–activity relationships of diarylheptanoids, related diarylheptanoids

Hisashi Matsuda; Shin Ando; Tomoko Kato; Toshio Morikawa; Masayuki Yoshikawa

2006-01-01

271

Lipopolysaccharide induces nitric oxide synthase expression and platelet-activating factor increases nitric oxide production in human fetal membranes in culture  

Microsoft Academic Search

BACKGROUND: Platelet-activating factor and nitric oxide may be involved in the initiation of human labour as inflammatory mediators. The aim of this study was to test whether platelet-activating factor and lipopolysaccharide were able to induce nitric oxide synthase expression and stimulate the production of nitric oxide in human fetal membrane explants in culture. METHODS: Fetal membranes were collected from Caesarean

Gunter Seyffarth; Paul N Nelson; Simon J Dunmore; Nalinda Rodrigo; Damian J Murphy; Ray J Carson

2004-01-01

272

Roles of iNOS and nNOS in sepsis-induced pulmonary apoptosis.  

PubMed

Apoptosis(programmed cell death) is induced in pulmonary cells and contributes to the pathogenesis of acute lung injury in septic humans. Previous studies have shown that nitric oxide (NO) is an important modulator of apoptosis; however, the functional role of NO derived from inducible NO synthase (iNOS) in sepsis-induced pulmonary apoptosis remains unknown. We measured pulmonary apoptosis in a rat model of Escherichia coli lipopolysaccharide (LPS)-induced sepsis in the absence and presence of the selective iNOS inhibitor 1400W. Four groups were studied 24 h after saline (control) or LPS injection in the absence and presence of 1400W pretreatment. Apoptosis was evaluated using DNA fragmentation, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining, and caspase activation. LPS administration significantly augmented pulmonary cell apoptosis and caspase-3 activity in airway and alveolar epithelial cells. Pretreatment with 1400W significantly enhanced LPS-induced pulmonary apoptosis and increased caspase-3 and -7 activation. The antiapoptotic effect of iNOS was confirmed in iNOS-/- mice, which developed a greater degree of pulmonary apoptosis both under control conditions and in response to LPS compared with wild-type mice. By comparison, genetic deletion of the neuronal NOS had no effect on LPS-induced pulmonary apoptosis. We conclude that NO derived from iNOS plays an important protective role against sepsis-induced pulmonary apoptosis. PMID:14660484

Rudkowski, Jill C; Barreiro, Esther; Harfouche, Rania; Goldberg, Peter; Kishta, Osama; D'Orleans-Juste, Pedro; Labonte, Julie; Lesur, Olivier; Hussain, Sabah N A

2003-12-05

273

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

274

Modulation of lipopolysaccharide-induced pro-inflammatory mediators by an extract of Glycyrrhiza glabra and its phytoconstituents  

Microsoft Academic Search

Objective  To evaluate the inhibitory property of de-glycyrrhizinated extract of Glycyrrhiza glabra root and its phytoconstituents (glabridin, isoliquiritigenin and glycyrrhizin) on LPS-induced production of pro-inflammatory\\u000a mediators.\\u000a \\u000a \\u000a \\u000a \\u000a Materials and methods  Inhibitory effect of G. glabra extract and its phytoconstituents were studied on lipopolysaccharide (LPS)-induced nitric oxide (NO), interleukin-1 beta\\u000a (IL-1 beta) and interleukin-6 (IL-6) levels in J774A.1 murine macrophages.\\u000a \\u000a \\u000a \\u000a \\u000a Results  \\u000a G. glabra and

P. Thiyagarajan; C. V. Chandrasekaran; H. B. Deepak; Amit Agarwal

2011-01-01

275

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

276

Phenylpropanoid ester from Zingiber officinale and their inhibitory effects on the production of nitric oxide.  

PubMed

A new phenylpropanoid ester mixture, (E)-geranylferulic acid (1a) and (Z)-geranylferulic acid (1b), along with 13 known compounds, [6]-gingerol (2), [8]-gingerol (3), [10]-gingerdione (4), 1-dehydro-[6]-gingerdione (5), 1-dehydro-[8]-gingerdione (6), [6]-paradol (7), [8]-paradol (8), [6]-gingeroldiacetate (9), 6-hydroxy-[6]-shogaol (10), galanolactone (11), trans-®-sesquiphellandrol (12), trans-sesquipiperitol (13), and 4?,5?-dihydroxybisabola-2,10-diene (14) were isolated from ethanol extract of Zingiber officinale. Their structures were determined based on the spectroscopic (1D, 2D-NMR and MS) and chemical evidence. All of the isolates were evaluated for their potential to inhibit LPS-induced production of nitric oxide in murine macrophage RAW264.7 cells. Compounds 1-12 were found to inhibit nitric oxide production with IC(50) values ranging from 5.5 to 28.5 ?M. PMID:22370785

Hong, Seong Su; Oh, Joa Sub

2012-02-28

277

Manganese potentiates lipopolysaccharide-induced expression of NOS2 in C6 glioma cells through mitochondrial-dependent activation of nuclear factor kappaB.  

PubMed

Neuronal injury in manganese neurotoxicity (manganism) is thought to involve activation of astroglial cells and subsequent overproduction of nitric oxide (NO) by inducible nitric oxide synthase (NOS2). Manganese (Mn) enhances the effects of proinflammatory cytokines on expression of NOS2 but the molecular basis for this effect has not been established. It was postulated in the present studies that Mn enhances expression of NOS2 through the cis-acting factor, nuclear factor kappaB (NF-kappaB). Exposure of C6 glioma cells to lipopopolysaccharide (LPS) resulted in increased expression of NOS2 and production of NO that was dramatically potentiated by Mn and was blocked through overexpression of mutant IkappaBalpha (S32/36A). LPS-induced DNA binding of p65/p50 was similarly enhanced by Mn and was decreased by mutant IkappaBalpha. Phosphorylation of IkappaBalpha was potentiated by Mn and LPS and was not blocked by U0126, a selective inhibitor of ERK1/2. Mn decreased mitochondrial membrane potential and increased matrix calcium, associated with a rise in intracellular reactive oxygen species (ROS) that was attenuated by the mitochondrial-specific antioxidant, MitoQ. Blocking mitochondrial ROS also attenuated the enhancing effect of Mn on LPS-induced phosphorylation of IkappaBalpha and expression of NOS2, suggesting a link between Mn-induced mitochondrial dysfunction and activation of NF-kappaB. Overexpression of a dominant-negative mutant of the NF-kappaB-interacting kinase (Nik) prevented enhancement of LPS-induced phosphorylation of IkappaBalpha by Mn. These data indicate that Mn augments LPS-induced expression of NOS2 in C6 cells by increasing mitochondrial ROS and activation of NF-kappaB. PMID:15010209

Barhoumi, Rola; Faske, Jennifer; Liu, Xuhong; Tjalkens, Ronald B

2004-03-30

278

[Inducible nitric oxide synthase expression and nitric oxide production by monocytes in systemic sclerosis].  

PubMed

We investigated nitric oxide (NO) production and inducible NO synthase (iNOS) expression by cultured peripheral blood mononuclear cells (PBMC) in systemic sclerosis (SSc). Eighteen patients with SSc were compared to two control groups: 16 rheumatoid arthritis patients (RA) and 23 mechanical sciatica patients. The sum of nitrites and nitrates was determined by fluorimetry in sera and spectrophotometry in supernatants. Inducible iNOS was detected in cultured PBMC by immunofluorescence, immunoblot and flow cytometry with or without IL-1 beta + TNF alpha, IL-4 or IFN gamma from day 1 to day 5. NO metabolite concentrations in the plasma were lower in SSc (34.3 mumol/l +/- 2.63 SEM) than in RA (48.3 mumol/l +/- 2.2; p < 0.02) and sciatica (43.3 mumol/l +/- 5.24; p < 0.03) patients. iNOS was detected in cultured monocytes in the 3 groups but induction occurred on day 1 in RA, day 2 in sciatica and only on day 3 in SSc, whatever the stimulus. The concentrations of NO metabolites are decreased in SSc patients and the induction of iNOS in PBMC is delayed. Low levels of NO, a vasodilator, may be involved in vasospasm, which is critical in SSc. This may suggest therapeutic implications. PMID:11501260

Menkčs, C J; Allanore, Y; Borderie, D; Hilliquin, P; Hernvann, A; Ekindjian, O; Kahan, A

2001-01-01

279

Nitric oxide mediates prostaglandins' deleterious effect on lipopolysaccharide-triggered murine fetal resorption  

PubMed Central

Genital tract bacterial infections could induce abortion and are some of the most common complications of pregnancy; however, the mechanisms remain unclear. We investigated the role of prostaglandins (PGs) in the mechanism of bacterial lipopolysaccharide (LPS)-induced pregnancy loss in a mouse model, and we hypothesized that PGs might play a central role in this action. LPS increased PG production in the uterus and decidua from early pregnant mice and stimulated cyclooxygenase (COX)-II mRNA and protein expression in the decidua but not in the uterus. We also observed that COX inhibitors prevented embryonic resorption (ER). To study the possible interaction between nitric oxide (NO) and PGs, we administered aminoguanidine, an inducible NO synthase inhibitor. NO inhibited basal PGE and PGF2? production in the decidua but activated their uterine synthesis and COX-II mRNA expression under septic conditions. A NO donor (S-nitroso-N-acetylpenicillamine) produced 100% ER and increased PG levels in the uterus and decidua. LPS-stimulated protein nitration was higher in the uterus than in the decidua. Quercetin, a peroxynitrite scavenger, did not reverse LPS-induced ER. Our results suggest that in a model of septic abortion characterized by increased PG levels, NO might nitrate and thus inhibit COX catalytic activity. ER prevention by COX inhibitors adds a possible clinical application to early pregnancy complications due to infections.

Aisemberg, J.; Vercelli, C.; Billi, S.; Ribeiro, M. L.; Ogando, D.; Meiss, R.; McCann, S. M.; Rettori, V.; Franchi, A. M.

2007-01-01

280

Nitric oxide mediates prostaglandins' deleterious effect on lipopolysaccharide-triggered murine fetal resorption.  

PubMed

Genital tract bacterial infections could induce abortion and are some of the most common complications of pregnancy; however, the mechanisms remain unclear. We investigated the role of prostaglandins (PGs) in the mechanism of bacterial lipopolysaccharide (LPS)-induced pregnancy loss in a mouse model, and we hypothesized that PGs might play a central role in this action. LPS increased PG production in the uterus and decidua from early pregnant mice and stimulated cyclooxygenase (COX)-II mRNA and protein expression in the decidua but not in the uterus. We also observed that COX inhibitors prevented embryonic resorption (ER). To study the possible interaction between nitric oxide (NO) and PGs, we administered aminoguanidine, an inducible NO synthase inhibitor. NO inhibited basal PGE and PGF(2alpha) production in the decidua but activated their uterine synthesis and COX-II mRNA expression under septic conditions. A NO donor (S-nitroso-N-acetylpenicillamine) produced 100% ER and increased PG levels in the uterus and decidua. LPS-stimulated protein nitration was higher in the uterus than in the decidua. Quercetin, a peroxynitrite scavenger, did not reverse LPS-induced ER. Our results suggest that in a model of septic abortion characterized by increased PG levels, NO might nitrate and thus inhibit COX catalytic activity. ER prevention by COX inhibitors adds a possible clinical application to early pregnancy complications due to infections. PMID:17460035

Aisemberg, J; Vercelli, C; Billi, S; Ribeiro, M L; Ogando, D; Meiss, R; McCann, S M; Rettori, V; Franchi, A M

2007-04-25

281

Inducible Nitric Oxide Synthase Genetic Polymorphism and Risk of Asbestosis  

PubMed Central

Asbestos, a known occupational pollutant, may upregulate the activity of inducible nitric oxide synthase (iNOS) and thus the production of nitric oxide (NO). This study investigated whether iNOS?(CCTTT)n polymorphism is associated with an increased asbestosis risk in exposed workers. The study cohort consisted of 262 cases with asbestosis and 265 controls with no asbestos-related disease. For each subject the cumulative asbestos exposure data were available. The number of CCTTT repeats was determined following PCR amplification of the iNOS promoter region. Logistic regression was performed to estimate asbestosis risk. The OR of asbestosis was 1.20 (95%? CI = 0.85–1.69) for the LL genotype compared to the combined SL and SS genotypes and 1.26 (95% CI = 0.86–1.85) for the LL genotype compared to the SL genotype. The results of this study are borderline significant and suggest a possible role of iNOS?(CCTTT)n polymorphism in the risk of asbestosis; however, further studies are needed.

Franko, Alenka; Dodic-Fikfak, Metoda; Arneric, Niko; Dolzan, Vita

2011-01-01

282

Nitric oxide-induced oxidation of alpha-tocopherol.  

PubMed

Exposure of alpha-tocopherol (alpha-T) to nitric oxide under aerobic conditions resulted in a complex oxidation process whose final outcome was dictated by the nature of the reaction medium. In a cyclohexane solution, a prevailing route led to a mixture of relatively unstable polar products positive to Griess reagent. On standing at room temperature these were partially converted to the novel 2,3-dimethyl-4-acetyl-4-hydroxy-5-nitroso-2-cyclopentenone derivative. Reaction of alpha-T via a secondary oxidation path led to the formation of alpha-tocopherylquinone (alpha-TQ) as well as of little amounts of the corresponding nitrite ester. A quite different product pattern was observed when the reaction was carried out on a suspension of alpha-T in 0.1 M phosphate buffer, pH 7.4. Besides a significant formation of alpha-TQ and its nitrite ester, product analysis revealed a characteristic pattern of apolar compounds consisting of a yellow dimer and a series of related oligomers. These results provide an improved chemical background to inquire into the role of alpha-T in nitric oxide-induced tissue injury. PMID:8931945

d'Ischia, M; Novellino, L

1996-10-01

283

Hypoxia-Induced Generation of Nitric Oxide Free Radicals in Cerebral Cortex of Newborn Guinea Pigs  

Microsoft Academic Search

Previous studies have shown that brain tissue hypoxia results in increased N-methyl-D-aspartate (NMDA) receptor activation and receptor-mediated increase in intracellular calcium which may activate Ca++-dependent nitric oxide synthase (NOS). The present study tested the hypothesis that tissue hypoxia will induce generation of nitric oxide (NO) free radicals in cerebral cortex of newborn guinea pigs. Nitric oxide free radical generation was

Om Prakash Mishra; Santina Zanelli; S. Tsuyoshi Ohnishi; Maria Delivoria-Papadopoulos

2000-01-01

284

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

Microsoft Academic Search

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

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

1993-01-01

285

Prior laparotomy or corticosterone potentiates lipopolysaccharide-induced fever and sickness behaviors.  

PubMed

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

2011-09-09

286

Prunella vulgaris extract and rosmarinic acid suppress lipopolysaccharide-induced alteration in human gingival fibroblasts.  

PubMed

Periodontitis is a chronic disease associated with inflammation of the tooth-supporting tissues. The inflammation is initiated by a group of gram-negative anaerobic bacteria. These express a number of irritating factors including a lipopolysaccharide (LPS), which plays a key role in periodontal disease development. Plant extracts with anti-inflammatory and anti-microbial properties have been shown to inhibit bacterial plaque formation and thus prevent chronic gingivitis. In this study we tested effects of Prunella vulgaris L. extract (PVE; 5, 10, 25microg/ml) and its component rosmarinic acid (RA; 1microg/ml) on LPS-induced oxidative damage and inflammation in human gingival fibroblasts. PVE and RA reduced reactive oxygen species (ROS) production, intracellular glutathione (GSH) depletion as well as lipid peroxidation in LPS-treated cells. Treatment with PVE and RA also inhibited LPS-induced up-regulation of interleukin 1beta (IL-1beta), interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF-alpha) and suppressed expression of inducible nitric oxide synthase (iNOS). The results indicate that PVE and RA are able to suppress LPS-induced biological changes in gingival fibroblasts. The effects of PVE and RA are presumably linked to their anti-inflammatory activities and thus use of PVE and RA may be relevant in modulating the inflammation process, including periodontal disease. PMID:19159670

Zdarilová, A; Svobodová, A; Simánek, V; Ulrichová, J

2008-12-30

287

Role of Kinase Suppressor of Ras-1 in Lipopolysaccharide-Induced Acute Lung Injury  

PubMed Central

Kinase suppressor of ras-1 (Ksr1) has been recently shown to be a central signaling molecule in the host response to Pseudomonas aeruginosa infections in the lung. Ksr1 functions to regulate the release of nitric oxide (NO)-radicals upon P. aeruginosa infections. Ksr1 also enhances Raf-1/MEK/ERK signaling and is involved in a variety of cellular responses, including cell differentiation, proliferation, and apoptosis. Here, we investigated whether Ksr1 is involved in the host immune response to lipopolysaccharide (LPS), one of the major components of gram-negative bacteria, in the lung. To this end, we induced an acute lung injury in wild type and Ksr1-deficient mice by intratracheal instillation of LPS. We found that LPS-induces acute lung injury, as characterized by cytokine expression, neutrophil infiltration and protein extrusion in wildtype mice. Ksr1-deficient mice showed a very similar reaction to LPS as the wildtype mice. In freshly isolated alveolar macrophages from wild type and Ksr1-deficient mice, LPS increased ERK activation, nuclear translocation of NF?B and expression of inflammatory cytokines and chemokines in a similar pattern. Inhibition of Src or Raf-1 blocked LPS-induced ERK activation. Taken together, these findings indicate that Ksr1 plays a dispensable role in LPS-induced ERK activation in alveolar macrophages and does not contribute to the development of acute lung injury in the LPS model.

Li, Xiang; Gulbins, Erich; Zhang, Yang

2013-01-01

288

Dried Ginger (Zingiber officinalis) Inhibits Inflammation in a Lipopolysaccharide-Induced Mouse Model.  

PubMed

Objectives. Ginger rhizomes have a long history of human use, especially with regards to their anti-inflammatory properties. However, the mechanisms by which ginger acts on lipopolysaccharide-(LPS-)induced inflammation have not yet been identified. We investigated the anti-inflammatory effects of dried Zingiber officinalis (DZO) on LPS-induced hepatic injury. Methods. ICR mice were given a DZO water extract (100, 1000?mg/kg) orally for three consecutive days. On the third day, they were administered by LPS intraperitoneally. To investigate the anti-inflammatory effects of DZO, histological, cytokine expression, and protein factor analyses were performed. Results. Oral administration of DZO significantly reduced pathological changes in the liver and proinflammatory cytokines including interferon-(IFN-) ? and interleukin-(IL-)6 in the serum. In addition, DZO inhibited LPS-induced NF- ? B activation by preventing degradation of the I ? B- ? , as well as the phosphorylation of ERK1/2, SAPK/JNK, and p38 MAPKs. These were associated with a decrease in the expression of inducible nitric oxide synthase (iNOS) and cyclooxyenase-2 (COX-2). Conclusions. Our data provide evidence for the hepatoprotective mechanisms of DZO as an anti-inflammatory effect. Furthermore, use of DZO to treat could provide therapeutic benefits in clinical settings. PMID:23935687

Choi, You Yeon; Kim, Mi Hye; Hong, Jongki; Kim, Sung-Hoon; Yang, Woong Mo

2013-06-27

289

Dried Ginger (Zingiber officinalis) Inhibits Inflammation in a Lipopolysaccharide-Induced Mouse Model  

PubMed Central

Objectives. Ginger rhizomes have a long history of human use, especially with regards to their anti-inflammatory properties. However, the mechanisms by which ginger acts on lipopolysaccharide-(LPS-)induced inflammation have not yet been identified. We investigated the anti-inflammatory effects of dried Zingiber officinalis (DZO) on LPS-induced hepatic injury. Methods. ICR mice were given a DZO water extract (100, 1000?mg/kg) orally for three consecutive days. On the third day, they were administered by LPS intraperitoneally. To investigate the anti-inflammatory effects of DZO, histological, cytokine expression, and protein factor analyses were performed. Results. Oral administration of DZO significantly reduced pathological changes in the liver and proinflammatory cytokines including interferon-(IFN-)? and interleukin-(IL-)6 in the serum. In addition, DZO inhibited LPS-induced NF-?B activation by preventing degradation of the I?B-?, as well as the phosphorylation of ERK1/2, SAPK/JNK, and p38 MAPKs. These were associated with a decrease in the expression of inducible nitric oxide synthase (iNOS) and cyclooxyenase-2 (COX-2). Conclusions. Our data provide evidence for the hepatoprotective mechanisms of DZO as an anti-inflammatory effect. Furthermore, use of DZO to treat could provide therapeutic benefits in clinical settings.

Choi, You Yeon; Kim, Mi Hye; Hong, Jongki; Kim, Sung-Hoon

2013-01-01

290

Modified apple polysaccharides suppress the migration and invasion of colorectal cancer cells induced by lipopolysaccharide.  

PubMed

Metastasis is the major cause of death in colorectal cancer (CRC). In colitis-associated carcinogenesis, the activation of nuclear factor-?B (NF-?B) occurs via lipopolysaccharide (LPS) binding to the toll-like receptor 4 (TLR4). The LPS/TLR4/NF-?B pathway contributes to the development and metastasis of colitis-associated colon cancer. In the present study, we hypothesized that an extracted modified Fuji apple polysaccharide (MAP) would alter the LPS/TLR4/NF-?B pathway. Thus, we evaluated the effect of MAP in vitro on the LPS/TLR4/NF-?B pathway in CRC cells (HT-29 and SW620 cells). The results suggest that (i) MAP competed with LPS for binding to TLR4 to reduce LPS-induced NF-?B expression and (ii) MAP suppressed the nuclear translocation of NF-?B p65. MAP significantly decreased LPS-induced expression of TLR4, cyclooxygenase-2, matrix metallopeptidase 9 (MMP9), matrix metallopeptidase 2, inducible nitric oxide synthase, and prostaglandin E2, and it increased the protein expression of the inhibitor of ?B? and NF-?B p65 in cytoplasm when it was given in combination with LPS. These results indicate that MAP suppressed LPS-induced migration and invasiveness of CRC cells by targeting the LPS/TLR4/NF-?B pathway. Therefore, we propose that MAP has potential for the clinical prevention of CRC cell metastasis. PMID:24074742

Zhang, Dian; Li, Yu-Hua; Mi, Man; Jiang, Feng-Liang; Yue, Zheng-Gang; Sun, Yang; Fan, Lei; Meng, Jin; Zhang, Xin; Liu, Li; Mei, Qi-Bing

2013-07-30

291

Methylmalonate-induced seizures are attenuated in inducible nitric oxide synthase knockout mice  

Microsoft Academic Search

Methylmalonic acidemias consist of a group of inherited neurometabolic disorders caused by deficiency of methylmalonyl-CoA mutase activity clinically and biochemically characterized by neurological dysfunction, methylmalonic acid (MMA) accumulation, mitochondrial failure and increased reactive species production. Although previous studies have suggested that nitric oxide (NO) plays a role in the neurotoxicity of MMA, the involvement of NO-induced nitrosative damage from inducible

Leandro Rodrigo Ribeiro; Michele Rechia Fighera; Mauro Schneider Oliveira; Ana Flávia Furian; Leonardo Magno Rambo; Ana Paula de Oliveira Ferreira; André Luiz Lopes Saraiva; Mauren Assis Souza; Frederico Diniz Lima; Danieli Valnes Magni; Renata Dezengrini; Eduardo Furtado Flores; D. Allan Butterfield; Juliano Ferreira; Adair Roberto Soares dos Santos; Carlos Fernando Mello; Luiz Fernando Freire Royes

2009-01-01

292

Role of inducible nitric oxide synthase in trinitrobenzene sulphonic acid induced colitis in mice  

Microsoft Academic Search

BACKGROUNDStudies using inhibitors of nitric oxide synthase (NOS) to date are inconclusive regarding the role of inducible NOS (iNOS) in intestinal inflammation.AIMS(1) To examine the role of iNOS in the development of chronic intestinal inflammation; (2) to identify the cellular source(s) of iNOS.METHODSColitis was induced by an intrarectal instillation of trinitrobenzene sulphonic acid (TNBS, 60 mg\\/ml, 30% ethanol), in wild

D-M McCafferty; M Miampamba; E Sihota; K A Sharkey; P Kubes

1999-01-01

293

Inducible nitric oxide synthase mediates bone development and P. gingivalis-induced alveolar bone loss  

Microsoft Academic Search

The role of inducible nitric oxide synthase (iNOS) in bone development and bacterially induced periodontal bone loss was examined using mice with targeted mutation of the iNOS gene. Femurs of iNOS KO mice showed 30% and 9% higher bone mineral density compared to wild type (WT) at 4 and 9 weeks of age, respectively. Micro-computed tomography revealed that cortical thickness

R. Gyurko; H. Shoji; R. A. Battaglino; G. Boustany; F. C. Gibson; C. A. Genco; P. Stashenko; T. E. Van Dyke

2005-01-01

294

Hypoxic Regulation of Inducible Nitric Oxide Synthase via Hypoxia Inducible Factor1 in Cardiac Myocytes  

Microsoft Academic Search

The relationship between hypoxia and regulation of nitric oxide synthase (NOS) in myocardial tissue is not well understood. We investigated the role of hypoxia inducible factor-1 (HIF-1) on expression of the inducible NOS (iNOS) in myocardial cells in vivo and in vitro. In situ hybridization in myocardial tissue from rats exposed to hypoxia for 3 weeks demonstrated increased iNOS mRNA

Frank Jung; Lisa A. Palmer; Nan Zhou; Roger A. Johns

295

Extracts of Magnoliae flos inhibit inducible nitric oxide synthase via ERK in human respiratory epithelial cells  

Microsoft Academic Search

Nitric oxide (NO) is a marker of pulmonary inflammation. In asthma, the levels of exhaled NO are elevated and the source of this increased NO is inducible nitric oxide synthase (iNOS) within airway epithelial cells. Epimagnolin and fargesin are compounds isolated from the ethanol extract of Magnoliae flos, the seed of the Magnolia plant and are used to treat nasal

Jin Ah Baek; Yang Deok Lee; Chan Bog Lee; Hyeon Kyu Go; Jin Pyo Kim; Jeong Ju Seo; Yang Keun Rhee; A Mi Kim; Dong Jib Na

2009-01-01

296

Spinal motoneuron synaptic plasticity after axotomy in the absence of inducible nitric oxide synthase  

Microsoft Academic Search

BACKGROUND: Astrocytes play a major role in preserving and restoring structural and physiological integrity following injury to the nervous system. After peripheral axotomy, reactive gliosis propagates within adjacent spinal segments, influenced by the local synthesis of nitric oxide (NO). The present work investigated the importance of inducible nitric oxide synthase (iNOS) activity in acute and late glial responses after injury

Amanda Emirandetti; Gustavo F Simőes; Renata G Zanon; Alexandre LR Oliveira

2010-01-01

297

Nitric oxide and hypoxia exacerbate alcohol-induced mitochondrial dysfunction in hepatocytes  

Microsoft Academic Search

Chronic alcohol consumption results in hepatotoxicity, steatosis, hypoxia, increased expression of inducible nitric oxide synthase (iNOS) and decreased activities of mitochondrial respiratory enzymes. The impact of these changes on cellular respiration and their interaction in a cellular setting is not well understood. In the present study we tested the hypothesis that nitric oxide (NO)-dependent modulation of cellular respiration and the

Blake R. Zelickson; Gloria A. Benavides; Michelle S. Johnson; Balu K. Chacko; Aparna Venkatraman; Aimee Landar; Angela M. Betancourt; Shannon M. Bailey; Victor M. Darley-Usmar

298

Time course of lipopolysaccharide-induced nitric oxide synthase mRNA expression in rat glomeruli  

Microsoft Academic Search

The decrease in glomerular filtration rate that is characteristic of sepsis has been shown to result from the local glomerular inhibition of endothelial nitric oxide synthase (NOS) by nitric oxide (NO) generated from the inducible isoform of NOS (iNOS). iNOS activation depends on de novo synthesis of both RNA and protein. Therefore it is assumed that several hours are required

Kobi Sade; Doron Schwartz; Yoram Wolman; Idit Schwartz; Tamara Chernichovski; Miriam Blum; Eli Brazowski; Shoshana Keynan; Itamar Raz; Roland C Blantz; Adrian Iaina

1999-01-01

299

Phlorofucofuroeckol A suppresses expression of inducible nitric oxide synthase, cyclooxygenase-2, and pro-inflammatory cytokines via inhibition of nuclear factor-?B, c-Jun NH2-terminal kinases, and Akt in microglial cells.  

PubMed

Microglial activation has been implicated in many neurological disorders for its inflammatory and neurotrophic effects. In this study, we investigated the effects of phlorofucofuroeckol A isolated from Ecklonia stolonifera Okamura on the production of inflammatory mediators in lipopolysaccharide (LPS)-stimulated microglia. Pre-treatment of phlorofucofuroeckol A attenuated the productions of nitric oxide, prostaglandin E2, and pro-inflammatory cytokines in LPS-stimulated microglia. Profoundly, phlorofucofuroeckol A treatment showed inactivation of nuclear factor-?B (NF-?B) by preventing the degradation of inhibitor ?B-? and the nuclear translocation of p65 NF-?B subunit. Moreover, phlorofucofuroeckol A inhibited the activation of c-Jun NH2-terminal kinases (JNKs), p38 mitogen-activated protein kinase (MAPK), and Akt, but not that of extracellular signal-regulated kinase. These results indicate that phlorofucofuroeckol A inhibits the LPS-induced expression of inflammatory mediators through inactivation of NF-?B, JNKs, p38 MAPK, and Akt pathways. These findings suggest that phlorofucofuroeckol A can be considered as a nutraceutical candidate for the treatment of neuroinflammation in neurodegenerative diseases. PMID:22993079

Kim, A-Reum; Lee, Min-Sup; Choi, Ji-Woong; Utsuki, Tadanobu; Kim, Jae-Il; Jang, Byeong-Churl; Kim, Hyeung-Rak

2013-04-01

300

Pulmonary hypertension triggered by lipopolysaccharide in ascites-susceptible and -resistant broilers is not amplified by aminoguanidine, a specific inhibitor of inducible nitric oxide synthase.  

PubMed

Nitric oxide (NO) is a potent pulmonary vasodilator that modulates the pulmonary vasoconstriction and pulmonary hypertension (PH) triggered by bacterial lipopolysaccharide (LPS) in broilers. The amplitude and duration of the LPS-induced PH are markedly enhanced following pretreatment with N(omega)-nitro-L-arginine methyl ester (L-NAME), which inhibits NO synthesis by both the constitutive (endothelial) and inducible (inflammatory) forms of nitric oxide synthase (eNOS and iNOS, respectively). In the present study L-NAME and the selective iNOS inhibitor aminoguanidine (AG) were administered to differentiate between iNOS and eNOS as the primary source of NO that attenuates the pulmonary vascular response to LPS. Clinically healthy male progeny from ascites-susceptible and ascites-resistant lines were anesthetized, and their pulmonary artery was cannulated. The initial pulmonary arterial pressure (PAP) was recorded, then the broilers either remained untreated (control group) or were injected i.v. with AG. Ten minutes later all birds received an i.v. injection of LPS, followed 40 min later by an i.v. injection of L-NAME. When compared with untreated controls, AG neither increased the baseline PAP nor did it increase or prolong the PH response to LPS. The ascites-susceptible broilers maintained a higher PAP than the ascites-resistant broilers throughout the experiment, and the ascites-resistant broilers exhibited greater relative increases in PAP in response to LPS than did the ascites-susceptible broilers. Within 40 min after the LPS injection, PAP subsided to a level that did not differ from the respective preinjection value for each line. Injecting L-NAME reversed the decline in PAP, and within 5 min PAP returned to hypertensive levels approaching the maximum peak PH response to LPS. The absence of any impact of AG coupled with the profound response to L-NAME indicates that NO synthesized by eNOS rather than iNOS likely modulated the acute (within 1 h) PH elicited by LPS. Evidently eNOS is activated by the increased shear stress exerted on the endothelium during the PH response to LPS, whereas LPS-mediated up-regulation of iNOS expression may take longer than 1 h before biologically effective quantities of NO are produced. PMID:16553285

Bowen, O T; Erf, G F; Anthony, N B; Wideman, R F

2006-03-01

301

Trail interacts redundantly with nitric oxide in rat astrocytes: potential contribution to neurodegenerative processes.  

PubMed

The proapoptotic cytokine TRAIL has been shown to enhance amyloid-beta-dependent neurotoxicity. Here are reported interactions between TRAIL and nitric oxide (NO) in cultured rat astrocytes in vitro. Rat astrocytes expressed all TRAIL receptor mRNAs and proteins. However, TRAIL failed in inducing apoptosis of astrocytes, whereas these cells released substantial amounts of nitrites. A TRAIL-neutralizing antibody was able to prevent LPS-induced iNOS expression in astrocytes. Interestingly, TRAIL induced its own expression in astrocytes. These data suggest that redundancy between TRAIL and NO in astrocytes could be fueling neuronal damage/death processes, potentially uncovering novel molecular targets for the treatment of neurodegenerative disorders. PMID:17067687

Cantarella, Giuseppina; Lempereur, Laurence; D'Alcamo, Maria Antonia; Risuglia, Nunziata; Cardile, Vera; Pennisi, Giuseppa; Scoto, Giovanna Maria; Bernardini, Renato

2006-10-24

302

Elevated Nitric Oxide Production in Children with Malarial Anemia: Hemozoin-Induced Nitric Oxide Synthase Type 2 Transcripts and Nitric Oxide in Blood Mononuclear Cells  

Microsoft Academic Search

Experiments outlined here investigate the role of nitric oxide (NO) in the pathogenesis of Plasmodium falciparum-induced malarial anemia (MA). The results show that ex vivo and in vitro NO synthase (NOS) activity in peripheral blood mononuclear cells (PBMCs) is significantly elevated in children with MA and inversely associated with hemoglobin levels. Additional experiments using PBMCs from non-malaria-exposed donors demonstrate that

Christopher C. Keller; Peter G. Kremsner; James B. Hittner; Mary A. Misukonis; J. Brice Weinberg; Douglas J. Perkins

2004-01-01

303

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.

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

2013-01-01

304

Rapid Reversibility of Nitric Oxide Induced Platelet Inhibition  

Microsoft Academic Search

Nitric oxide is known to attenuate human platelet activation. Mechanistically this is achieved by stimulation of soluble guanylyl cyclase, followed by cGMP production, and concomitant protein phosphorylation. Although inhibitory actions of nitric oxide on various platelet parameters are well documented, considerably less information is available on the reversibility of this effect. In order to study the onset of proaggregatory signaling

Bernhard Brüne; Kerstin Hanstein

1998-01-01

305

Laser Induced Fluorescence Measurements and Modeling of Nitric Oxide in High-Pressure Premixed Flames.  

National Technical Information Service (NTIS)

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 capabiliti...

J. R. Reisel N. M. Laurendeau

1994-01-01

306

Lipopolysaccharide induces nitric oxide synthase expression and platelet-activating factor increases nitric oxide production in human fetal membranes in culture  

PubMed Central

Background Platelet-activating factor and nitric oxide may be involved in the initiation of human labour as inflammatory mediators. The aim of this study was to test whether platelet-activating factor and lipopolysaccharide were able to induce nitric oxide synthase expression and stimulate the production of nitric oxide in human fetal membrane explants in culture. Methods Fetal membranes were collected from Caesarean sections at term. RNA was extracted from membranes and subjected to a qualitative RT-PCR to assess the baseline expression of iNOS. Discs of fetal membranes were cultured for 24 hours in the presence of platelet-activating factor at a dose range of 0.1 nanomolar – 1 micomolar or 1 microgram/ml lipopolysaccharide. Nitric oxide production was measured via nitrite ions in the culture medium and mRNA for iNOS was detected by RT-PCR. Results Culturing the membrane discs in medium containing serum induced nitric oxide synthase expression and platelet-activating factor significantly stimulated the production of nitric oxide under these conditions. When cultured without serum inducible nitric oxide synthase expression was induced by lipopolysaccharide, but not by platelet-activating factor. Conclusion Platelet-activating factor may have a role in the initiation of labour, at term or preterm, via the increased local production of nitric oxide as an inflammatory mediator. In this model of intrauterine infection, lipopolysaccharide was found to induce iNOS expression by fetal membranes, and this mechanism could be involved in preterm labour.

Seyffarth, Gunter; Nelson, Paul N; Dunmore, Simon J; Rodrigo, Nalinda; Murphy, Damian J; Carson, Ray J

2004-01-01

307

Benzylamine and methylamine, substrates of semicarbazide-sensitive amine oxidase, attenuate inflammatory response induced by lipopolysaccharide.  

PubMed

Current evidence indicates that semicarbazide-sensitive amine oxidase (SSAO) substrates possess insulin-mimic effect, which was thought to play an anti-inflammatory role. The purpose of the present study was to determine whether SSAO substrates benzylamine (BZA) and methylamine (MA) attenuate inflammatory response induced by lipopolysaccharide (LPS). BALB/c mice peritoneal macrophages (PMs) that express SSAO and RAW264.7 mouse macrophages that do not express SSAO were used in vitro studies. Experimental mice were given BZA or MA through intraperitoneal injection before LPS challenge. The results showed that BZA or MA treatment significantly reduced LPS-induced pro-inflammatory mediators (nitric oxide, TNF-?) production, the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2, and glucose consumption in murine PMs, but not in RAW264.7 cell line. The metabolites of BZA or MA catalyzed by SSAO, hydrogen peroxide, formaldehyde, and benzaldehyde could also significantly decrease LPS-induced nitric oxide and TNF-? production, iNOS and COX-2 expression, and glucose consumption in vitro. In addition, BZA or MA administration could significantly decrease plasma pro-inflammatory mediators and the expression of iNOS and COX-2 in liver and lung, and could also attenuate LPS-induced transient hyperglycemia and chronic hypoglycemia. These findings indicated that substrates of SSAO might be involved in the anti-inflammatory effects. The metabolites of BZA and MA catalyzed by SSAO might be responsible for the anti-inflammatory effects. Moreover, BZA or MA administration could be useful for normalization of glucose disposal during endotoxemia. PMID:21414430

Lin, Zhexuan; Li, Hui; Luo, Hongjun; Zhang, Yuan; Luo, Wenhong

2011-03-15

308

Inducible nitric oxide: an autoregulatory feedback inhibitor of vascular inflammation.  

PubMed

Inducible nitric oxide (iNO) is produced at sites of vascular inflammation by resident and nonresident vascular wall cells, but its role in the inflammatory process is not known. In this study, we show that a novel function of iNO is to terminate inflammatory processes. We find that iNO produced by murine macrophage-like cells, RAW264.7, can inhibit cytokine-induced endothelial cell activation in a separated and mixed endothelial-RAW264.7 coculture system. Both iNO production and endothelial VCAM-1 expression were induced simultaneously with bacterial LPS and murine-specific IFN-gamma. Inhibition of iNO synthase (iNOS) activity with N omega-monomethyl-L-arginine in endothelial-RAW264.7 cocultures, stimulated with murine-specific IFN-gamma and LPS, decreased iNO production by 86%, augmented VCAM-1 and iNOS expression in endothelial and RAW264.7 cells, respectively, and increased monocyte adhesion to the endothelial cell surface. Transient transfection studies using various VCAM-1 promoter constructs demonstrated that inhibitory effects of iNO on VCAM-1 gene transcription were mediated, in part, by inhibitory effects of iNO on kappa B cis-acting elements. Immunofluorescence studies using an Ab to the RelA (p65) subunit of nuclear factor-kappa B revealed that iNO inhibited the activation of nuclear factor-kappa B. These studies indicate that iNO attenuates iNOS expression in macrophages and inhibits monocyte adhesion to endothelial cells, and suggest that endogenously derived iNO may be an important autoregulatory inhibitor of vascular inflammation. PMID:9712068

Peng, H B; Spiecker, M; Liao, J K

1998-08-15

309

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

310

Inducible Nitric Oxide Synthase Mediates Hypoxia-Induced Hypoxia-Inducible Factor1? Activation and Vascular Endothelial Growth Factor Expression in Oxygen-Induced Retinopathy  

Microsoft Academic Search

Objective: Previous studies provided evidence that many factors contribute to retinal angiogenesis, including inducible nitric oxide synthase (iNOS), hypoxia-inducible factor-1? (HIF-1?) and vascular endothelial growth factor (VEGF). But the role of nitric oxide generated by iNOS in the regulation of expression of hypoxia-inducible genes in retinopathy of prematurity remains unclear. So we sought to better define the molecular basis of

Tao He; Ming Ai; Xiao-Hui Zhao; Yi-Qiao Xing

2007-01-01

311

Nitric oxide mediates renal vasodilation during erythropoietin-induced polycythemia.  

PubMed

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 erythropoietin-induced erythrocytosis is mediated by the L-arginine-NO pathway. Groups of Sprague-Dawley rats received thrice weekly injections of erythropoietin (E) for two to five weeks; responses were contrasted with normal rats (N) which received sham injections. The first group was studied after five weeks of erythropoietin injections which led to sharp increases in Hct (E: 72 +/- 3 vs. N: 44 +/- 1%) and mean arterial pressure (MAP: 126 +/- 3 vs. 107 +/- 3 mm Hg). These rats had an elevated basal RBF whether measured by the clearance and renal extraction of PAH or by a transit-time renal blood flow meter. Subsequent groups were studied after two to three weeks of erythropoietin which raised the Hct more modestly to 59 +/- 2%. In this group, the basal MAP was similar in E and N rats. Graded doses of the NO synthase inhibitor, N omega-monomethyl-L-arginine (L-NMA) led to a steeper rise in MAP in E than N; at the highest doses, the MAP had increased by 36 +/- 2 in E and 23 +/- 3 mm Hg in N (P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8377385

Wilcox, C S; Deng, X; Doll, A H; Snellen, H; Welch, W J

1993-08-01

312

Regulation of Inducible Nitric Oxide Synthase Gene in Glial Cells  

PubMed Central

Elevated levels of NO produced within the central nervous system (CNS) are associated with the pathogenesis of neuroinflammatory and neurodegenerative human diseases such as multiple sclerosis, HIV dementia, brain ischemia, trauma, Parkinson's disease, and Alzheimer's disease. Resident glial cells in the CNS (astroglia and microglia) express inducible nitric oxide synthase (iNOS) and produce high levels of NO in response to a wide variety of proinflammatory and degenerative stimuli. Although pathways resulting in the expression of iNOS may vary in two different glial cells of different species, the intracellular signaling events required for the expression of iNOS in these cells are slowly becoming clear. Various signaling cascades converge to activate several transcription factors that control the transcription of iNOS in glial cells. The present review summarizes different results and discusses current understandings about signaling mechanisms for the induction of iNOS expression in activated glial cells. A complete understanding of the regulation of iNOS expression in glial cells is expected to identify novel targets for therapeutic intervention in NO-mediated neurological disorders.

Saha, Ramendra N.; Pahan, Kalipada

2007-01-01

313

EXOGENOUS NITRIC OXIDE INDUCES PROTECTION DURING HEMORRHAGIC SHOCK  

PubMed Central

This study analyzed the systemic and microvascular hemodynamic changes related to increased nitric oxide (NO) availability during the early phase of hemorrhagic shock. Hemodynamic responses to hemorrhagic shock were studied in the hamster window chamber. Exogenous NO was administered in the form of nitrosothiols (nitrosylated glutathione, GSNO) and was given prior the onset of hemorrhage. Moderate hemorrhage was induced by arterial controlled bleeding of 50% of the blood volume, and the hypovolemic shock was followed over 90 min. Animals pre-treated with GSNO maintained systemic and microvascular conditions during hypovolemic hemorrhagic shock, when compared to animal treated with glutathione (GSH) or the sham group. Low concentrations of NO released during the early phase of hypovolemic shock from GSNO mitigated arteriolar vasoconstriction, increased capillary perfusion and venous return, and improved cardiac function (recovered of blood pressure and stabilized heart rate). GSNO's effect on resistance vessels influenced intravascular pressure redistribution and blood flow, preventing tissue ischemia. In conclusion, increases in NO availability during the early phase of hypovolemic shock, could preserve cardiac function and microvascular perfusion, sustaining organ function. Direct translation into a clinical scenario may be limited, although the pathophysiological importance of NO in the early phase of hypovolemia is clearly highlighted here.

Cabrales, Pedro; Tsai, Amy G.; Intaglietta, Marcos

2009-01-01

314

GAPDH regulates cellular heme insertion into inducible nitric oxide synthase.  

PubMed

Heme proteins play essential roles in biology, but little is known about heme transport inside mammalian cells or how heme is inserted into soluble proteins. We recently found that nitric oxide (NO) blocks cells from inserting heme into several proteins, including cytochrome P450s, hemoglobin, NO synthases, and catalase. This finding led us to explore the basis for NO inhibition and to identify cytosolic proteins that may be involved, using inducible NO synthase (iNOS) as a model target. Surprisingly, we found that GAPDH plays a key role. GAPDH was associated with iNOS in cells. Pure GAPDH bound tightly to heme or to iNOS in an NO-sensitive manner. GAPDH knockdown inhibited heme insertion into iNOS and a GAPDH mutant with defective heme binding acted as a dominant negative inhibitor of iNOS heme insertion. Exposing cells to NO either from a chemical donor or by iNOS induction caused GAPDH to become S-nitrosylated at Cys152. Expressing a GAPDH C152S mutant in cells or providing a drug to selectively block GAPDH S-nitrosylation both made heme insertion into iNOS resistant to the NO inhibition. We propose that GAPDH delivers heme to iNOS through a process that is regulated by its S-nitrosylation. Our findings may uncover a fundamental step in intracellular heme trafficking, and reveal a mechanism whereby NO can govern the process. PMID:20921417

Chakravarti, Ritu; Aulak, Kulwant S; Fox, Paul L; Stuehr, Dennis J

2010-10-04

315

Estrogen Up-Regulates Inducible Nitric Oxide Synthase, Nitric Oxide, and Cyclooxygenase2 in Splenocytes Activated with T Cell Stimulants: Role of Interferon  

Microsoft Academic Search

Estrogen is implicated in many autoimmune diseases and is a robust immunomodulator. For example, it regulates inter- feron (IFN)-, a cytokine believed to up-regulate inducible nitric oxide synthase (iNOS). A notable gap in the literature is a lack of information on the regulation of nitric oxide in im- mune tissues by estrogen. We now show that activation of splenocytes with

Ebru Karpuzoglu; Jillian B. Fenaux; Rebecca A. Phillips; Andrea J. Lengi; Francois Elvinger; S. Ansar Ahmed

2005-01-01

316

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

317

Influence of the estrous cycle on tolerance development to LPS-induced sickness behaviors in rats.  

PubMed

The relations between the estrous cycle, inflammatory responses and the development of tolerance to endotoxin were examined. Female Long-Evans rats were injected intraperitoneally with lipopolysaccharide (LPS; 200 microg/kg) or saline vehicle at 08:00h on either diestrus (D) or proestrus (P). Ninety-five minutes after injection locomotor activity was assessed in an automated non-novel open-field for 20 min. To assess tolerance development to LPS, rats were re-injected at the next identical stage (i.e. 4 days later; groups: DD, PP) or at the alternate stage (i.e. 6 days later; groups: DP, PD) of the estrous cycle and locomotor activity was again assessed. On Test Day 1 all groups injected with LPS exhibited similar significant activity decrements, regardless of the stage of the estrous cycle. However, on Test Day 2 rats which received both injections of LPS during proestrus (PP) showed no signs of tolerance development, whereas rats in all other groups were tolerant to LPS. In a follow up study, the time between injections was extended to 8 days. Still the animals injected both times at proestrus showed no signs of tolerance to LPS after the second injection. Thus, the stages of the estrous cycle both at the time of initial exposure and of re-exposure appear critical in the formation of behavioral tolerance to LPS in rats. PMID:16413135

Engeland, Christopher G; Kavaliers, Martin; Ossenkopp, Klaus-Peter

2006-01-18

318

Infusion of a Glucose Solution Reduces Autophagy in the Liver after LPS-induced Systemic Inflammation  

Microsoft Academic Search

Autophagy is a natural process by which a cell maintains homeostasis, usually taking place unnoticed by adjacent cells. Glucose\\u000a is involved in a negative feedback loop in autophagy. Autophagy is characterized by the induction and secretion of HMGB1,\\u000a yet the nature of the inflammatory response during and the effect of glucose administration on autophagy are not well understood.\\u000a Systemic inflammation

Satoshi Hagiwara; Hideo Iwasaka; Akira Hasegawa; Kyousuke Kudo; Jyunya Kusaka; Yoshimasa Oyama; Takayuki Noguchi

319

The costimulatory immunogen LPS induces the B-Cell clones that infiltrate transplanted human kidneys  

PubMed Central

The mechanism of chronic rejection of transplanted human kidneys is unknown. An understanding of this process is important because, chronic rejection ultimately leads to loss of the kidney allograft in most transplants. One feature of chronic rejection is the infiltration of ectopic B-cell clusters that are clonal into the transplanted kidney. We now show that the antibodies produced by these B-cells react strongly with the core carbohydrate region of LPS. Since LPS is a costimulatory immunogen that can react with both the B-cell receptor (BCR) and the Toll-like receptor 4 (TLR4), these results suggest a mechanism for the selective pressure that leads to clonality of these B-cell clusters and opens the possibility that infection and the attendant exposure to LPS plays a role in the chronic rejection of human kidney transplants. If confirmed by clinical studies, these results suggest that treating patients with signs of chronic rejection with antibiotics may improve kidney allograft survival.

Grover, Rajesh K.; Cheng, Julong; Peng, Yingjie; Jones, Teresa M.; Ruiz, Diana I.; Ulevitch, Richard J.; Glass, John I.; Dennis, Edward A.; Salomon, Daniel R.; Lerner, Richard A.

2012-01-01

320

LPS-induced lung inflammation is linked to increased epithelial permeability: role of MLCK  

Microsoft Academic Search

The respiratory system is directly exposed to low levels of lipopolysaccharide (LPS), present as a contaminant on airborne particles. In cystic fibrosis, the prevailing data identify structural changes of the airway epithelium, as well as tight junction dilatation. This study was aimed at determining the contribution of myosin light chain kinase to maintaining airway epithelium barrier integrity in the lung

H. Eutamene; V. Theodorou; F. Schmidlin; V. Tondereau; R. Garcia-Villar; C. Salvador-Cartier; M. Chovet; C. Bertrand; L. Bueno

2005-01-01

321

NF-?B p50 facilitates neutrophil accumulation during LPS-induced pulmonary inflammation  

Microsoft Academic Search

BACKGROUND: Transcription factors have distinct functions in regulating immune responses. During Escherichia coli pneumonia, deficiency of NF-?B p50 increases gene expression and neutrophil recruitment, suggesting that p50 normally limits these innate immune responses. p50-deficient mice were used to determine how p50 regulates responses to a simpler, non-viable bacterial stimulus in the lungs, E. coli lipopolysaccharide (LPS). RESULTS: In contrast to

Joseph P Mizgerd; Michal M Lupa; Matt S Spieker

2004-01-01

322

ROLE OF CELL SIGNALING IN PROTECTION FROM DIESEL AND LPS INDUCED ACUTE LUNG INJURY  

EPA Science Inventory

We have previously demonstrated in CD-1 mice that pre-administration of N-acetyl cysteine (NAC) or the p38 MAP kinase inhibitor (SB203580) reduces acute lung injury and inflammation following pulmonary exposures to diesel exhaust particles (DEP) or lipopolysaccharide (LPS). Here ...

323

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

Microsoft Academic Search

Not Available Bibtex entry for this abstract Preferred format for this abstract (see Preferences) Find Similar Abstracts: Use: Authors Title Return: Query Results Return items starting with number Query Form Database: Astronomy Physics arXiv e-prints

Francisco Ramírez-Gómez; Pablo A. Ortiz-Pineda; Gabriela Rivera-Cardona; José E. García-Arrarás; Sebastian D. Fugmann

2009-01-01

324

Periodontal pathogen Aggregatibacter actinomycetemcomitans LPS induces mitochondria-dependent-apoptosis in human placental trophoblasts  

Microsoft Academic Search

ObjectiveIncreasing evidence suggests an association between periodontal disease and low birthweight (LBW); however the underlying molecular mechanisms are yet to be fully elucidated. In this study, we performed a microarray analysis to observe the human placental trophoblast-like BeWo cells response to lipopolysaccharide (LPS) from periodontopathogen Aggregatibacter actinomycetemcomitans (Aa), in order to investigate the molecular basis of mechanisms for periodontitis-associated LBW.

Y. Li; Y. Shibata; L. Zhang; N. Kuboyama; Y. Abiko

2011-01-01

325

Skeletal Muscle PGC-1? Is Required for Maintaining an Acute LPS-Induced TNF? Response  

PubMed Central

Many lifestyle-related diseases are associated with low-grade inflammation and peroxisome proliferator activated receptor ? coactivator (PGC)-1? has been suggested to be protective against low-grade inflammation. However, whether these anti-inflammatory properties affect acute inflammation is not known. The aim of the present study was therefore to investigate the role of muscle PGC-1? in acute inflammation. Quadriceps muscles were removed from 10-week old whole body PGC-1? knockout (KO), muscle specific PGC-1? KO (MKO) and muscle-specific PGC-1? overexpression mice (TG), 2 hours after an intraperitoneal injection of either 0.8 µg LPS/g body weight or saline. Basal TNF? mRNA content was lower in skeletal muscle of whole body PGC-1? KO mice and in accordance TG mice showed increased TNF? mRNA and protein level relative to WT, indicating a possible PGC-1? mediated regulation of TNF?. Basal p65 phosphorylation was increased in TG mice possibly explaining the elevated TNF? expression in these mice. Systemically, TG mice had reduced basal plasma TNF? levels compared with WT suggesting a protective effect against systemic low-grade inflammation in these animals. While TG mice reached similar TNF? levels as WT and showed more marked induction in plasma TNF? than WT after LPS injection, MKO PGC-1? mice had a reduced plasma TNF? and skeletal muscle TNF? mRNA response to LPS. In conclusion, the present findings suggest that PGC-1? enhances basal TNF? expression in skeletal muscle and indicate that PGC-1? does not exert anti-inflammatory effects during acute inflammation. Lack of skeletal muscle PGC-1? seems however to impair the acute TNF? response, which may reflect a phenotype more susceptible to infections as also observed in type 2 diabetes patients.

Olesen, Jesper; Larsson, Signe; Iversen, Ninna; Yousafzai, Simi; Hellsten, Ylva; Pilegaard, Henriette

2012-01-01

326

AURANOFIN, AS AN ANTI-RHEUMATIC GOLD COMPOUND SUPPRESSES LPS-INDUCED HOMODIMERIZATION OF TLR4  

Technology Transfer Automated Retrieval System (TEKTRAN)

Toll-like receptors (TLRs), which are activated by invading microorganisms or endogenous molecules, evoke immune and inflammatory responses. TLR activation is closely linked to the development of many chronic inflammatory diseases including rheumatoid arthritis. Auranofin, an Au(I) compound, is a we...

327

INHIBITION OF LPS-INDUCED SPLENOCYTE PROLIFERATION BY ORTHO-SUBSTITUTED POLYCHLORINATED BIPHENYL CONGENERS. (R826687)  

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

328

Synergistic effects of antibodies against high-mobility group box 1 and tumor necrosis factor-? antibodies on D-(+)-galactosamine hydrochloride/lipopolysaccharide-induced acute liver failure.  

PubMed

High-mobility group box 1 (HMGB1) protein is released into the serum after tissue damage, and serves as a warning signal to enhance the inflammatory response. Acute liver injury is one of the diseases that starts with tissue damage and ends with systemic inflammation. We used D-(+)-galactosamine hydrochloride (D-GalN)/lipopolysaccharide (LPS)-treated mice as an acute liver injury model to explore the functions of HMGB1 in more detail. HMGB1 is released into the serum at a very early stage of D-GalN/LPS-induced acute liver injury. It upregulates the expression of tumor necrosis factor-? (TNF-?), interleukin-6, inducible nitric oxide synthase, and tissue factor. TNF-? and HMGB1 form a positive feedback loop to amplify the downstream signals. mAbs against HMGB1 and TNF-? have synergistic effects in protecting mice from D-GalN/LPS-induced acute liver failure. The results suggest that HMGB1 is a key mediator in D-GalN/LPS-induced acute liver injury. Tissue damage and cell necrosis shortly after administration of D-GalN and LPS lead to early HMGB1 release, and HMGB1 acts synergistically with TNF-? to promote pathological processes in acute liver failure. PMID:23331758

Wang, Wei; Sun, Li; Deng, Yonghao; Tang, Jie

2013-02-14

329

Mercury induces the expression of cyclooxygenase-2 and inducible nitric oxide synthase.  

PubMed

Nuclear factor-?B (NF-?B) is a transcription factor that mediates the inducible expression of a variety of genes involved in immune and inflammatory responses. NF-?B activation induces numerous proinflammatory gene products including cytokines, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS). The divalent heavy metal mercury has been used for thousands of years. Although mercury is clearly toxic to most mammalian organ systems, especially the immune system, exposure has still increased in some areas of the world. However, the underlying toxic mechanism is not clearly identified. Here, we report biochemical evidence that mercury alone induces NF-?B activation, resulting in the induced expression of COX-2 and iNOS. The results suggest that mercury can induce inflammatory diseases by lowering host defense. PMID:22080037

Park, Hye-Jeong; Youn, Hyung-Sun

2011-11-11

330

Chemoprevention with phytochemicals targeting inducible nitric oxide synthase.  

PubMed

A regulated low level of nitric oxide (NO) production in the body is essential for maintaining homeostasis (neuroprotection, vasorelaxation, etc.), though certain pathophysiological conditions associated with inflammation involve de novo synthesis of inducible NO synthase (iNOS) in immune cells, including macrophages. A large body of evidence indicates that many inflammatory diseases, such as colitis and gastritis, as well as many types of cancer, occur through sustained and elevated activation of this particular enzyme. The biochemical process of iNOS protein expression is tightly regulated and complex, in which the endotoxin lipopolysaccharide selectively binds to toll-like receptor 4 and thereby activates its adaptor protein MyD88, which in turn targets downstream proteins such as IRAK and TRAF6. This leads to functional activation of key protein kinases, including IkB kinases and mitogen-activated protein kinases (MAPKs), such as p38 MAPK, JNK1/2, and ERK1/2, all of which are involved in activating key transcription factors, including nuclear factor-kappaB and activator protein-1. In addition, the production of proinflammatory cytokines such as interferon-gamma and interleukin-12 potentiates iNOS induction in autocrine fashions. Meanwhile, an LPS-stimulated p38 MAPK pathway plays a pivotal role in the stabilization of iNOS mRNA, which has the AU-rich element in its 3'-untranslated region, for rapid NO production. Thus, suppression and/or inhibition of the above-mentioned signaling molecules may have a great potential for the prevention and treatment of inflammation-associated carcinogenesis. In fact, there have been numerous reports of phytochemicals found capable of targeting NO production by unique mechanisms, including polyphenols, terpenoids, and others. This review article briefly highlights the molecular mechanisms underlying endotoxin-induced iNOS expression in macrophages, and also focuses on promising natural agents that may be useful for anti-inflammation and anticarcinogenesis strategies. PMID:19367123

Murakami, Akira

2009-04-07

331

Inducible nitric oxide synthase suppresses the development of allograft arteriosclerosis.  

PubMed Central

In cardiac transplantation, chronic rejection takes the form of an occlusive vasculopathy. The mechanism underlying this disorder remains unclear. The purpose of this study was to investigate the role nitric oxide (NO) may play in the development of allograft arteriosclerosis. Rat aortic allografts from ACI donors to Wistar Furth recipients with a strong genetic disparity in both major and minor histocompatibility antigens were used for transplantation. Allografts collected at 28 d were found to have significant increases in both inducible NO synthase (iNOS) mRNA and protein as well as in intimal thickness when compared with isografts. Inhibiting NO production with an iNOS inhibitor increased the intimal thickening by 57.2%, indicating that NO suppresses the development of allograft arteriosclerosis. Next, we evaluated the effect of cyclosporine (CsA) on iNOS expression and allograft arteriosclerosis. CsA (10 mg/kg/d) suppressed the expression of iNOS in response to balloon-induced aortic injury. Similarly, CsA inhibited iNOS expression in the aortic allografts, associated with a 65% increase in intimal thickening. Finally, we investigated the effect of adenoviral-mediated iNOS gene transfer on allograft arteriosclerosis. Transduction with iNOS using an adenoviral vector suppressed completely the development of allograft arteriosclerosis in both untreated recipients and recipients treated with CsA. These results suggest that the early immune-mediated upregulation in iNOS expression partially protects aortic allografts from the development of allograft arteriosclerosis, and that iNOS gene transfer strategies may prove useful in preventing the development of this otherwise untreatable disease process.

Shears, L L; Kawaharada, N; Tzeng, E; Billiar, T R; Watkins, S C; Kovesdi, I; Lizonova, A; Pham, S M

1997-01-01

332

Exercise-induced modulation of endothelial nitric oxide production.  

PubMed

In the arterial wall nitric oxide (NO) is the key transmitter for endothelium-dependent regulation of vascular tone. It is produced in intact endothelial cells by endothelial NO synthase (eNOS) as the key enzyme from L-arginine. Endothelial NO generation is highly regulated by mechanical, humoral, and metabolic factors. The regulation of NO synthesis occurs at different levels: ENOS gene polymorphisms are related to eNOS expression and activity and may potentially increase coronary event rate, mRNA expression is influenced by estrogen status and shear stress, mRNA stability is enhanced by vascular endothelial growth factor (VEGF), and final enzyme activity is regulated by the phosphorylation status at serine/threonine residues. Released from endothelial cells NO is rapidly transported to the neighboring vascular smooth muscle cells (VSMCs), where it induces the production of cGMP as a second messenger. CGMP in turn increases Ca2+ uptake into intracellular calcium stores thereby lowering [Ca2+]i and inducing VSMC relaxation and vasodilation. On its way to the VSMCs NO may be prematurely degraded by reactive oxygen species. On the other hand, chronic endurance exercise with regular bouts of increased laminar flow along the endothelium has the potential to increase eNOS mRNA expression and phosphorylation via AKT (protein kinase B) and to reduce oxidative stress by improving antioxidative protection. The growing knowledge about the complex regulation of NO synthesis and degradation in cardiovascular diseases and its response to exercise has led to a new understanding of the protective effects of long-term habitual physical activity against atherosclerotic heart disease and vascular aging. PMID:21235458

Gielen, Stephan; Sandri, Marcus; Erbs, Sandra; Adams, Volker

2011-09-01

333

Evidence for bidirectional changes in nitric oxide synthase activity in the rat striatum after excitotoxically (quinolinic acid) induced degeneration  

Microsoft Academic Search

Nitric oxide, a gaseous inter- and intracellular messenger, is thought to mediate neurotoxicity via excitatory amino acid receptors which may contribute to the pathogenesis of a variety of neuronal diseases. Excitotoxin lesions induced by quinolinic acid were made unilaterally in the rat striatum to study biochemically, light- and electron microscopically the possible involvement of the nitric oxide synthesizing enzyme nitric

W. Schmidt; G. Wolf; J. Calka; H. H. H. W. Schmidt

1995-01-01

334

Nitric oxide induces cell death in Taxus cells  

Microsoft Academic Search

Sodium nitroprusside (SNP), a nitric oxide donor, or centrifugation at 150 times unit gravity, caused a nitric oxide burst in oocyte-derived Taxusbrevifolia 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

M. Cristina Pedroso; Jose R. Magalhaes; Don Durzan

2000-01-01

335

Role of nitric oxide in amphetamine-induced sensitization of schedule-induced polydipsic rats  

Microsoft Academic Search

Rationale  Repeated injections of amphetamine (AMPH) can progressively augment behavioral responses, a phenomenon known as behavioral\\u000a sensitization. AMPH-induced behavioral sensitization can be demonstrated in a rat model of schedule-induced polydipsia (SIP).\\u000a \\u000a \\u000a \\u000a \\u000a Objectives  The aim of this study was to investigate the effects of a nonspecific nitric oxide (NO) synthase inhibitor, NG-nitro arginine methyl ester (l-NAME), on the AMPH sensitization effects in SIP.

Yia-Ping Liu; Che-Se Tung; Pai-Jone Lin; Fang-Jung Wan

336

Regulation of prostaglandin production by nitric oxide; an in vivo analysis.  

PubMed Central

1. Endotoxin E. Coli lipopolysaccharide (LPS)-treatment in conscious, restrained rats increased plasma and urinary prostaglandin (PG) and nitric oxide (NO) production. Inducible cyclo-oxygenase (COX-2) and nitric oxide synthase (iNOS) expression accounted for the LPS-induced PG and NO release since the glucocorticoid, dexamethasone inhibited both effects. Thus, LPS (4 mg kg-1) increased the plasma levels of nitrite/nitrate from 14 +/- 1 to 84 +/- 7 microM within 3 h and this rise was inhibited to 35 +/- 1 microM by dexamethasone. Levels of 6-keto PGF1 alpha in the plasma were below the detection limit of the assay (< 0.2 ng ml-1). However, 3 h after the injection of LPS these levels rose to 2.6 +/- 0.2 ng ml-1 and to 0.7 +/- 0.01 ng ml-1 after LPS in rats that received dexamethasone. 2. The induced enzymes were inhibited in vivo with selective COX and NOS inhibitors. Furthermore, NOS inhibitors, that did not affect COX activity in vitro markedly suppressed PG production in the LPS-treated animals. For instance, the LPS-induced increased in plasma nitrite/nitrate and 6-keto PGF1 alpha at 3 h was decreased to 18 +/- 2 microM and 0.5 +/- 0.02 ng ml-1, 23 +/- 1 microM and 0.7 +/- 0.01 ng ml-1, 29 +/- 2 microM and 1 +/- 0.01 ng ml-1 in rats treated with LPS in the presence of the NOS inhibitors NG-monomethyl-L-arginine, NG-nitro arginine methyl ester and aminoguanidine, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Salvemini, D; Settle, S L; Masferrer, J L; Seibert, K; Currie, M G; Needleman, P

1995-01-01

337

Nilotinib ameliorates lipopolysaccharide-induced acute lung injury in rats  

SciTech Connect

The present study aimed to investigate the effect of the new tyrosine kinase inhibitor, nilotinib on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in rats and explore its possible mechanisms. Male Sprague-Dawley rats were given nilotinib (10 mg/kg) by oral gavage twice daily for 1 week prior to exposure to aerosolized LPS. At 24 h after LPS exposure, bronchoalveolar lavage fluid (BALF) samples and lung tissue were collected. The lung wet/dry weight (W/D) ratio, protein level and the number of inflammatory cells in the BALF were determined. Optical microscopy was performed to examine the pathological changes in lungs. Malondialdehyde (MDA) content, superoxidase dismutase (SOD) and reduced glutathione (GSH) activities as well as nitrite/nitrate (NO{sub 2}{sup -}/NO{sub 3}{sup -}) levels were measured in lung tissues. The expression of inflammatory cytokines, tumor necrosis factor-{alpha} (TNF-{alpha}), transforming growth factor-{beta}{sub 1} (TGF-{beta}{sub 1}) and inducible nitric oxide synthase (iNOS) were determined in lung tissues. Treatment with nilotinib prior to LPS exposure significantly attenuated the LPS-induced pulmonary edema, as it significantly decreased lung W/D ratio, protein concentration and the accumulation of the inflammatory cells in the BALF. This was supported by the histopathological examination which revealed marked attenuation of LPS-induced ALI in nilotinib treated rats. In addition, nilotinib significantly increased SOD and GSH activities with significant decrease in MDA content in the lung. Nilotinib also reduced LPS mediated overproduction of pulmonary NO{sub 2}{sup -}/NO{sub 3}{sup -} levels. Importantly, nilotinib caused down-regulation of the inflammatory cytokines TNF-{alpha}, TGF-{beta}{sub 1} and iNOS levels in the lung. Taken together, these results demonstrate the protective effects of nilotinib against the LPS-induced ALI. This effect can be attributed to nilotinib ability to counteract the inflammatory cells infiltration and hence ROS generation and regulate cytokine effects. - Research highlights: > The protective effects of nilotinib against LPS-induced ALI in rats were studied. > Nilotinib showed potent anti-inflammatory activity as it attenuated PMN infiltration and hence ROS generation. > In addition, nilotinib caused down-regulation of proinflammatory cytokine production.

El-Agamy, Dina S., E-mail: dinaagamy1@yahoo.com

2011-06-01

338

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.

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

2013-01-01

339

Glycogen synthase kinase-3 negatively regulates anti-inflammatory interleukin-10 for lipopolysaccharide-induced iNOS/NO biosynthesis and RANTES production in microglial cells.  

PubMed

The inflammatory effects of glycogen synthase kinase-3 (GSK-3) have been identified; however, the potential mechanism is still controversial. In this study, we investigated the effects of GSK-3-mediated interleukin-10 (IL-10) inhibition on lipopolysaccharide (LPS)-induced inflammation. Treatment with GSK-3 inhibitor significantly blocked LPS-induced nitric oxide (NO) production as well as inducible NO synthase (iNOS) expression in BV2 murine microglial cells and primary rat microglia-enriched cultures. Using an antibody array and enzyme-linked immunosorbent assay, we found that GSK-3-inhibitor treatment blocked LPS-induced upregulation of regulated on activation normal T-cell expressed and secreted (RANTES) and increased IL-10 expression. The time kinetics and dose-response relations were confirmed. Reverse transcription-polymerase chain reaction showed changes on the messenger RNA level as well. Inhibiting GSK-3 using short-interference RNA, and transfecting cells with dominant-negative GSK-3beta, blocked LPS-elicited NO and RANTES expression but increased IL-10 expression. In contrast, GSK-3beta overexpression upregulated NO and RANTES but downregulated IL-10 in LPS-stimulated cells. Treating cells with anti-IL-10 neutralizing antibodies to prevent GSK-3 from downregulating NO and RANTES showed that the anti-inflammatory effects are, at least in part, IL-10-dependent. The involvement of Akt, extracellular signal-regulated kinase, p38 mitogen-activated protein kinase and nuclear factor-kappaB that positively regulated IL-10 was demonstrated. Furthermore, inhibiting GSK-3 increased the nuclear translocation of transcription factors, that all important for IL-10 expression, including CCAAT/enhancer-binding protein beat (C/EBPbeta), C/EBPdelta, cAMP response binding element protein and NF-kappaB. Taken together, these findings reveal that LPS induces iNOS/NO biosynthesis and RANTES production through a mechanism involving GSK-3-mediated IL-10 downregulation. PMID:19175796

Huang, Wei-Ching; Lin, Yee-Shin; Wang, Chi-Yun; Tsai, Cheng-Chieh; Tseng, Hsiang-Chi; Chen, Chia-Ling; Lu, Pei-Jung; Chen, Po-See; Qian, Li; Hong, Jau-Shyong; Lin, Chiou-Feng

2008-10-29

340

Pichinde virus induces microvascular endothelial cell permeability through the production of nitric oxide  

PubMed Central

This report is the first to demonstrate infection of human endothelial cells by Pichinde virus (PIC). PIC infection induces an upregulation of the inducible nitric oxide synthase gene; as well as an increase in detectable nitric oxide (NO). PIC induces an increase in permeability in endothelial cell monolayers which can be abrogated at all measured timepoints with the addition of a nitric oxide synthase inhibitor, indicating a role for NO in the alteration of endothelial barrier function. Because NO has shown antiviral activity against some viruses, viral titer was measured after addition of the NO synthase inhibitor and found to have no effect in altering virus load in infected EC. The NO synthase inhibition also has no effect on levels of activated caspases induced by PIC infection. Taken together, these data indicate NO production induced by Pichinde virus infection has a pathogenic effect on endothelial cell monolayer permeability.

Brocato, Rebecca L; Voss, Thomas G

2009-01-01

341

Cardiac weight in hypertension induced by nitric oxide synthase blockade.  

PubMed

Wistar rats given a nitric oxide synthase inhibitor, NG-nitro-L-arginine-methyl ester (L-NAME), for 4 weeks develop time- and dose-dependent hypertension without cardiac hypertrophy. This initial study of the relation between left ventricular weight and L-NAME-induced hypertension has now been extended by giving 50 mg/kg per day L-NAME to Wistar rats (n = 30) for 8 weeks and comparing results with those from control rats (n = 10) and two-kidney, one clip rats (n = 14). Although L-NAME rats and two-kidney, one clip rats had increased systolic blood pressures during the last 3 weeks of the experiment (202 +/- 24 and 224 +/- 16 mm Hg, respectively), the ratio of left ventricular weight to body weight of L-NAME rats (2.12 +/- 0.32 mg/g) was not statistically different from that of control rats (1.93 +/- 0.13 mg/g), whereas that of two-kidney, one clip rats was increased (2.85 +/- 0.20 mg/g). The plasma renin activity of L-NAME rats was not significantly different from that of control rats. Two L-NAME rat subgroups were defined according to the presence of left ventricular hypertrophy (ratio of left ventricular weight to body weight > 2.19 mg/g, control mean +2 SD) (6 of 25) or its absence (19 of 25). Systolic blood pressure, plasma renin activity, and cardiac angiotensin converting enzyme activity of L-NAME rats with left ventricular hypertrophy were significantly higher than those of the subgroup without.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8349331

Arnal, J F; el Amrani, A I; Chatellier, G; Ménard, J; Michel, J B

1993-09-01

342

Inducible nitric oxide synthase haplotype associated with migraine and aura.  

PubMed

Migraine is a complex neurological disorder with a clear neurogenic inflammatory component apparently including enhanced nitric oxide (NO) formation. Excessive NO amounts possibly contributing to migraine are derived from increased expression and activity of inducible NO synthase (iNOS). We tested the hypothesis that two functional, clinically relevant iNOS genetic polymorphisms (C(-1026)A-rs2779249 and G2087A-rs2297518) are associated with migraine with or without aura. We studied 142 healthy women without migraine (control group) and 200 women with migraine divided into two groups: 148 with migraine without aura (MWA) and 52 with aura (MA). Genotypes were determined by real-time polymerase chain reaction using the Taqman(®) allele discrimination assays. The PHASE 2.1 software was used to estimate the haplotypes. The A allele for the G2087A polymorphism was more commonly found in the MA group than in the MWA group (28 vs. 18%; P < 0.05). No other significant differences in the alleles or genotypes distributions were found (P > 0.05). The haplotype combining both A alleles for the two polymorphisms was more commonly found in the MA group than in the control group or in the MWA group (19 vs. 10 or 8%; P = 0.0245 or 0.0027, respectively). Our findings indicate that the G2087A and the C(-1026)A polymorphism in the iNOS gene affect the susceptibility to migraine with aura when their effects are combined within haplotypes, whereas the G2087A affects the susceptibility to aura in migraine patients. These finding may have therapeutic implications when examining the effects of selective iNOS inhibitors. PMID:22234503

de O S Mansur, Thiago; Gonçalves, Flavia M; Martins-Oliveira, Alisson; Speciali, Jose G; Dach, Fabiola; Lacchini, Riccardo; Tanus-Santos, Jose E

2012-01-11

343

Ketamine Inhibits Calcium Elevation and Hydroxyl Radical and Nitric Oxide Production in Lipopolysaccharide-Stimulated NR8383 Alveolar Macrophages.  

PubMed

Macrophages play a critical role in mediating inflammatory processes; activated macrophages respond to endotoxin by releasing pro-inflammatory cytokines including tumor necrosis factor-? (TNF-?), interleukin-1? (IL-1?), and IL-6. Ketamine, a widely used anesthetic agent, has unequivocally anti-inflammatory effects in vivo and in vitro. However, the detailed mechanisms for the anti-inflammatory effects of ketamine in microglia have not been elucidated yet. This study aimed to evaluate the effects of ketamine on lipopolysaccharide (LPS)-induced nitric oxide (NO), hydroxyl radical (·OH) production, and intracellular calcium accumulation in macrophages. Macrophages were pretreated with ketamine at the concentrations of 10, 100, and 1,000 ?M 1 h before LPS stimulation. The production of NO and ·OH in the culture supernatant of macrophages was assayed by Griess Reagent Kit. LPS enhanced NO and ·OH production and provoked a significant intracellular calcium elevation. With the concentrations higher than 100 ?M, ketamine inhibited LPS-induced NO and ·OH accumulation and intracellular calcium elevation. However, a low concentration of ketamine (10 ?M) did not exert anti-inflammatory effects. These results suggest that intracellular calcium elevation is, at least, partially involved in the inhibitory effect of ketamine. PMID:23595868

Zhang, Xiaobao; Feng, Jiying; Zhu, Pin; Zhao, Zhibin

2013-10-01

344

Enhanced Collagen Accumulation Following Direct Transfection of the Inducible Nitric Oxide Synthase Gene in Cutaneous Wounds  

Microsoft Academic Search

Inducible nitric oxide synthase (iNOS) is expressed during cutaneous wound repair. Mounting evidence suggests that wound nitric oxide (NO) augments collagen accumulation. We hypothesized thatin vivotransfection of wound cells with the iNOS gene would increase physiological wound NO levels and thus augment collagen accumulation. Polyvinyl alcohol sponges were instilled with a mammalian expression plasmid (pMP6) containing either the chloramphenicol acetyl

Frank J. Thornton; Michael R. Schäffer; Maria B. Witte; Lyle L. Moldawer; Sally L. D. MacKay; Amer Abouhamze; Cynthia L. Tannahill; Adrian Barbul

1998-01-01

345

Inducible nitric oxide synthase does not mediate brain damage after transient focal cerebral ischemia in mice  

Microsoft Academic Search

Nitric oxide produced by the inducible nitric oxide synthase (iNOS) is believed to participate in the pathogenic events after cerebral ischemia. In this study, we examined the expression of iNOS in the brain after transient focal cerebral ischemia in mice. We detected differential expression of exons 2 and 3 of iNOS mRNA (16-fold upregulation at 24 to 72 h after

Harald Prüss; Konstantin Prass; Leyli Ghaeni; Milan Milosevic; Claudia Muselmann; Dorette Freyer; Georg Royl; Uwe Reuter; Nevena Baeva; Ulrich Dirnagl; Andreas Meisel; Josef Priller

2008-01-01

346

Superoxide and Peroxynitrite Generation from Inducible Nitric Oxide Synthase in Macrophages  

Microsoft Academic Search

Superoxide (O2{\\\\cdot}) and nitric oxide (NO) act to kill invading microbes in phagocytes. In macrophages NO is synthesized by inducible nitric oxide synthase (iNOS, NOS 2) from L-arginine (L-Arg) and oxygen; however, O2{\\\\cdot} was thought to be produced mainly by NADPH oxidase. Electron paramagnetic resonance (EPR) spin trapping experiments performed in murine macrophages demonstrate a novel pathway of O2{\\\\cdot} generation.

Yong Xia; Jay L. Zweier

1997-01-01

347

Plasmodium berghei ookinetes induce nitric oxide production in Anopheles pseudopunctipennis midguts cultured in vitro  

Microsoft Academic Search

The Anopheles pseudopunctipennis nitric oxide synthase gene (ApNOS) was identified and its partial sequence showed high homology with NOS from A. stephensi, A. gambiae (putative sequence), and Drosophila melanogaster. ApNOS was mainly expressed in male and female adult mosquitoes and was induced by a blood meal. Nitric oxide (NO) was produced by in vitro-cultured mosquito midguts inoculated by enema with

Antonia Herrera-Ortíz; Humberto Lanz-Mendoza; Jesús Martínez-Barnetche; Salvador Hernández-Martínez; Cuauhtémoc Villarreal-Trevińo; Liliana Aguilar-Marcelino; Mario H. Rodríguez

2004-01-01

348

Evidence for the role of nitric oxide in caffeine-induced locomotor activity in mice  

Microsoft Academic Search

Rationale Nitric oxide (NO) is implicated in the acute locomotor activating effects of some addictive drugs such as amphetamine and cocaine, but has not been investigated in the case of caffeine. Objectives We investigated the effects of a nitric oxide synthase (NOS) inhibitor N?-Nitro-l-arginine methyl ester (l-NAME) and a combination of l-arginine, a NO precursor, and l-NAME on caffeine induced

Hakan Kayir; I. Tayfun Uzbay

2004-01-01

349

Pharmacological strategies for the regulation of inducible nitric oxide synthase: Neurodegenerative versus neuroprotective mechanisms  

Microsoft Academic Search

Inducible nitric oxide synthase (iNOS) is one of three NOS isoforms generating nitric oxide (NO) by the conversion of l-arginine to l-citrulline. iNOS has been found to be a major contributor to initiation\\/exacerbation of the central nervous system (CNS) inflammatory\\/degenerative conditions through the production of excessive NO which generates reactive nitrogen species (RNSs). Activation of iNOS and NO generation has

Ravinder Pannu; Inderjit Singh

2006-01-01

350

Heat shock enhances transcriptional activation of the murine inducible nitric oxide synthase gene  

Microsoft Academic Search

There is considerable interest in determining the conditions leading to enhanced inducible nitric oxide synthase (iNOS) gene expression and nitric oxide (NO) biosynthesis. Using in vivo footprinting, we demonstrate that heat shock of murine macrophages concurrent with lipopolysaccharide (LPS) treatment stimulated changes in guanine methylation sensitivity at -898\\/9, at a putative partial heat shock element (HSE) and at -893\\/4, a

Christopher E. P. Goldring; Sylvie Reveneau; Aurélie Chantome; Alena Pance; Christophe Fleury; David A. Hume; David Sester; Bernard Mignotte; Jean-François Jeannin

2000-01-01

351

The harmony of the spheres: inducible nitric oxide synthase and related genes in pancreatic beta cells  

Microsoft Academic Search

Summary  The radical nitric oxide (NO) is a possible mediator of pancreatic beta-cell damage in insulin-dependent diabetes mellitus\\u000a (IDDM). NO is produced by the enzyme nitric oxide synthase (NOS), in a reaction where arginine is the main substrate. There\\u000a are different isoforms of NOS, but in the context of immune mediated beta-cell damage the inducible form of NOS (iNOS) is\\u000a the

D. L. Eizirik; M. Flodstriim; A. E. Karlsen; N. Welsh

1996-01-01

352

Reduction of neuronal and inducible nitric oxide synthase gene expression in patients with cystic fibrosis  

Microsoft Academic Search

As a consequence of diminished nitric oxide synthase (NOS) protein concentration, the airway concentration of nitric oxide\\u000a (NO) is reduced in patients with cystic fibrosis (CF). This appears to lead to a reduced elimination of such microorganisms\\u000a as Pseudomonas aeruginosa. The objective of this study was to analyze whether inducible (iNOS), endothelial (eNOS) and neuronal (bNOS) NOS are reduced\\u000a at

Jörg Dötsch; Jan Puls; Thorsten Klimek; Wolfgang Rascher

2002-01-01

353

Inducible nitric oxide synthase following hypoxia in rat cultured glial cells  

Microsoft Academic Search

Nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) exerts inhibitory and cytotoxic effects on various cells including neuronal cells. In the present study, we examined the ability of rat glial cells to produce NO following hypoxia\\/reoxygenation in vitro by measuring nitrite. The levels of nitrite produced in the cultured media of glial cells significantly increased after 12-h hypoxia

Makoto Kawase; Hiroyuki Kinouchi; Ichiro Kato; Atsuya Akabane; Takeo Kondo; Shouichi Arai; Miki Fujimura; Hiroshi Okamoto; Takashi Yoshimoto

1996-01-01

354

Nitric oxide inhibitory substances from the rhizomes of Dioscorea membranacea.  

PubMed

Thai medicinal plants locally known as Hua-Khao-Yen were examined for their inhibitory activities against lipopolysaccharide (LPS) induced nitric oxide (NO) production in RAW 264.7 cell lines. Among the plant species studied, an ethanolic extract of Dioscorea membranacea exhibited the most potent inhibitory activity, with an IC(50) value of 23.6 microg/ml. From this extract, eight compounds [two naphthofuranoxepins (1, 2), one phenanthraquinone (3), three steroids (4-6) and two steroidal saponins (7, 8)] were isolated and further investigated for their inhibitory properties of NO production. It was found that diosgenin-3-O-alpha-L-rhamnosyl (1-->2)-beta-D-glucopyranoside (7) possessed the highest activity (IC(50)=3.5 microM), followed by dioscoreanone (3, IC(50)=9.8 microM) and dioscorealide B (2, IC(50)=24.9 microM). Regarding structural requirements of diosgenin derivatives for NO production inhibitory activity, compound 7 which has a rhamnoglucosyl moiety at C-3 exhibited much higher activity than compounds that have either a diglucosyl substitution (8) or its aglycone (9); whereas, hydroxyl substitution at position 8 of naphthofuranoxepin derivatives conferred higher activity than the methoxyl group. It is concluded that diosgenin-3-O-alpha-L-rhamnosyl (1-->2)-beta-D-glucopyranoside (7), dioscoreanone (3) and dioscorealide B (2) are active principles for NO inhibitory activity of Dioscorea membranacea. Compounds 1-3 were also tested for the inhibitory effect on LPS-induced TNF-alpha release in RAW 264.7 cells. The result revealed that 3 possessed potent activity against TNF-alpha release with an IC(50) value of 17.6 microM, whereas, 1 and 2 exhibited mild activity. The present study may support the use of Dioscorea membranacea by Thai traditional doctors for treatment of the inflammatory diseases. PMID:16979312

Tewtrakul, Supinya; Itharat, Arunporn

2006-08-15

355

O-GlcNAc transferase inhibits LPS-mediated expression of inducible nitric oxide synthase through an increased interaction with mSin3A in RAW264.7 cells.  

PubMed

O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT), which catalyzes the addition of a single ?-N-GlcNAc unit to target proteins, has been shown to act as a transcriptional regulator. In the current study, we discovered that OGT exerted inhibitory effects on the LPS-driven activation of NF-?B and inducible nitric oxide synthase (iNOS). In response to LPS, OGT exhibited an increased interaction with the transcriptional corepressor mammalian Sin3A (mSin3A). Furthermore, mSin3A, histone deacetylase (HDAC)1, and HDAC2 displayed increased binding to the iNOS promoter in response to LPS. Treatment with GlcN, in contrast, inhibits LPS-induced inflammation and decreased LPS-mediated recruitment of OGT, mSin3A, and HDACs. LPS treatment also resulted in the hypo-O-GlcNAcylation of mSin3A, which was reversed by GlcN. When the effect of the HDAC inhibitor trichostatin A (TSA) on LPS- and/or GlcN-mediated iNOS protein/mRNA induction was investigated, the results revealed that TSA dose dependently enhanced iNOS expression in response to LPS and/or GlcN. In addition, histone acetyltransferases, p300, and cAMP response element-binding protein-binding protein (CBP) enhanced LPS- and/or GlcN-induced iNOS protein expression. These results collectively suggest that OGT inhibits LPS-driven NF-?B activation and subsequent iNOS transcription by modulating histone acetylation either directly or indirectly. PMID:23824843

Hwang, So-Young; Hwang, Ji-Sun; Kim, Song-Yi; Han, Inn-Oc

2013-07-03

356

Phenolic-rich fraction from Rhus verniciflua Stokes (RVS) suppress inflammatory response via NF-?B and JNK pathway in lipopolysaccharide-induced RAW 264.7 macrophages  

Microsoft Academic Search

The effects of phenolic-rich fraction (PRF) from Rhus verniciflua Stokes (Anacardiaceae) on the activities of cellular signaling molecules that mediate inflammatory responses in LPS-induced RAW 264.7 macrophages were investigated. At various concentrations of PRF significantly inhibited NO, PGE2 and TNF-? production in LPS-induced RAW 264.7 macrophage cells. The PRF also significantly inhibited iNOS and COX-2 protein expression in LPS-induced RAW

Chang Hwa Jung; Ji Hye Kim; Myung Hee Hong; Ho Moon Seog; Seong Hoon Oh; Pan Jae Lee; Gyung Jun Kim; Hyung Min Kim; Jae Young Um; Seong-Gyu Ko

2007-01-01

357

Kaempferol glycosides from the twigs of Cinnamomum osmophloeum and their nitric oxide production inhibitory activities.  

PubMed

In the present study, ethanolic extract of twigs from Cinnamomum osmophloeum led to isolate nine kaempferol glycosides including two new kaempferol triglycosides that were characterized as kaempferol 3-O-?-D-xylopyranosyl-(1?2)-?-L-arabinofuranosyl-7-O-?-L-rhamnopyranoside (1) and kaempferol 3-O-?-D-xylopyranosyl-(1?2)-?-L-rhamnopyranosyl-7-O-?-L-rhamnopyranoside (2). The structures of these compounds were assigned by the application of 1D and 2D NMR spectroscopy and other techniques. Among these nine compounds, kaempferol 7-O-?-L-rhamnopyranoside (9) revealed inhibitory effect against LPS-induced production of nitric oxide in RAW 264.7 macrophages with an IC(50) value of 41.2 ?M. It also slightly reduced PGE(2) accumulation by 26% at the concentration of 50 ?M. PMID:23174526

Lin, Huan-You; Chang, Shang-Tzen

2012-10-22

358

Time course and cellular localization of inducible nitric oxide synthases expression during cardiac allograft rejection  

Microsoft Academic Search

Background. We have demonstrated that inhibition of inducible nitric oxide synthase (NOS) ameliorated acute cardiac allograft rejection. This study determined the time course and cellular localization of inducible NOS expression during the histologic progression of unmodified acute rat cardiac allograft rejection.Methods. Tissue from syngeneic (ACI to ACI) and allogeneic (Lewis to ACI) transplants were harvested on postoperative days 3 through

Neil K Worrall; Thomas P Misko; Mitchell D Botney; Patrick M Sullivan; Jia-J Hui; Gloria M Suau; Pamela T Manning; T. Bruce Ferguson

1999-01-01

359

Protective effect of inducible nitric oxide synthase inhibitor on pancreas transplantation in rats  

Microsoft Academic Search

AIM: To investigate the effect of inducible nitric oxide synthase inhibitor, aminoguanidine, on pancreas transplantation in rats. METHODS: A model of pancreas transplantation was established in rats. Streptozotocin-induced diabetic male Wistar rats were randomly assigned to sham-operation control group (n = 6), transplant control group (n = 6), and aminoguanidine (AG) treatment group (n = 18). In the AG group,

Bai-Feng Li; Yong-Feng Liu; Ying Cheng; Ke-Zhong Zhang; Tie-Min Li; Ning Zhao

2007-01-01

360

Paeonol attenuates microglia-mediated inflammation and oxidative stress-induced neurotoxicity in rat primary microglia and cortical neurons.  

PubMed

Inflammation and oxidative stress play important roles in the pathogenesis of neurodegenerative disorders such as stroke, traumatic injury, Parkinson disease, and Alzheimer disease. Paeonol, a natural compound extracted from Moutan cortex, is a potent anti-inflammatory and antioxidative agent. The aim of this study was to investigate the neuroprotective mechanisms of paeonol on lipopolysaccharide (LPS)-induced inflammation in rat primary microglia and 6-hydroxydopamine-induced oxidative damage in cortical neurons. In LPS-treated microglia, paeonol attenuated the overexpression of inducible nitric oxide synthase and cyclooxygenase 2, leading to the decrease in nitric oxide and prostaglandin E2 production, respectively. Paeonol also suppressed LPS-induced phosphorylation of extracellular signal-regulated kinase and Jun N-terminal kinase. In addition, LPS-stimulated NADPH oxidase activation and reactive oxygen species production were attenuated by paeonol. Paeonol-induced upregulation of heme oxygenase 1 was also observed. Moreover, paeonol attenuated LPS-treated microglia culture medium-induced neuron cells death. Posttreatment with paeonol also reduced inflammatory responses in LPS-activated microglia and increased cell viability in LPS-treated microglia culture medium-treated neurons. Furthermore, in 6-hydroxydopamine-treated cortical neurons, paeonol not only decreased reactive oxygen species production but also increased cell viability, superoxide dismutase activity, and the antiapoptotic protein B-cell lymphoma 2 expression. Taken together, the present results suggest that paeonol might be a potential neuroprotective agent via inhibiting microglia-mediated inflammation and oxidative stress-induced neuronal damage. PMID:22089194

Tseng, Yu-Ting; Hsu, Ya-Yun; Shih, Yu-Tzu; Lo, Yi-Ching

2012-03-01

361

Suppression of lipopolysaccharide-induced expression of inducible nitric oxide synthase by brazilin in RAW 264.7 macrophage cells  

Microsoft Academic Search

Brazilin (7,11b-dihydrobenz[b]indeno[1,2-d]pyran-3,6a,9,10 (6H)-tetrol) isolated from Caesalpinia sappan has been known as a natural red pigment. Many studies suggest that inducible isoform of nitric oxide synthase (NOS) plays an important role in inflammation and carcinogenesis. On this line, we evaluated the inhibitory effect of brazilin on nitric oxide (NO) production and investigated its mechanism of action. As a result, brazilin exhibited

In-Kyung Bae; Hye-Young Min; Ah-Reum Han; Eun-Kyoung Seo; Sang Kook Lee

2005-01-01

362

Signalling Mechanisms Involved in the Induction of Inducible Nitric Oxide Synthase by Lactobacillus Rhamnosus GG, Endotoxin, and Lipoteichoic Acid  

Microsoft Academic Search

Background and Aims: Probiotic Lactobacillus rhamnosus GG (Lactobacillus GG) has been found beneficial in the treatment of viral and antibiotic-associated diarrhea. Recently, it has also been shown to induce nitric oxide (NO) production, and have some other immunostimulatory effects. The aim of the present study was to investigate the mechanisms involved in the induction of inducible nitric oxide synthase (iNOS)

Riku Korhonen; Riitta Korpela; Eeva Moilanen

2002-01-01

363

Mycophenolate mofetil reduces renal cortical inducible nitric oxide synthase mRNA expression and diminishes glomerulosclerosis in MRL\\/ lpr mice  

Microsoft Academic Search

Overexpression of inducible nitric oxide synthase (iNOS) has been implicated in the pathogenesis of lupus glomerulonephritis. Mycophenolate mofetil (MMF), a novel immunosuppressive agent, is currently used in organ transplantation and under evaluation for treatment of autoimmune disorders. Mycophenolic acid, the active metabolite of MMF, has been shown to suppress cytokine-induced nitric oxide production in vitro. The aim of this study

Chun-Chen Yu; Chih-Wei Yang; Mai-Szu Wu; Yi-Ching Ko; Chiung-Tseng Huang; Jenn-Jye Hong; Chiu-Ching Huang

2001-01-01

364

Evaluating the Role of Inducible Nitric Oxide Synthase Using a Novel and Selective Inducible Nitric Oxide Synthase Inhibitor in Septic Lung Injury Produced by Cecal Ligation and Puncture  

Microsoft Academic Search

We studied the role of inducible nitric oxide synthase (iNOS) in sep- tic lung injury using a novel and selective iNOS inhibitor (a fused pi- peridine derivative; ONO-1714) following a cecal ligation and punc- ture (CLP) procedure. All rats that received CLP died within 48 h after the intervention. The subcutaneous injection of ONO-1714 at 0.03 mg\\/kg every 12 h

IKU OKAMOTO; MASAYOSHI ABE; KAZUHIKO SHIBATA; NAOMI SHIMIZU; NORIYUKI SAKATA; TAKESHI KATSURAGI; KEIICHI TANAKA

365

Lipopolysaccharides of Brucella abortus and Brucella melitensis Induce Nitric Oxide Synthesis in Rat Peritoneal Macrophages  

Microsoft Academic Search

Received 28 October 1999\\/Returned for modification 16 November 1999\\/Accepted 6 December 1999 Smooth lipopolysaccharide (S-LPS) and lipid A of Brucella abortus and Brucella melitensis induced the production of nitric oxide (NO) by rat adherent peritoneal cells, but they induced lower levels of production of NO than Escherichia coli LPS. The participation of the inducible isoform of NO synthase (iNOS) was

LUIS LOPEZ-URRUTIA; ANDRES ALONSO; MARIA LUISA NIETO; YOLANDA BAYON; ANTONIO ORDUNA; MARIANO SANCHEZ CRESPO

2000-01-01

366

Involvement of nitric oxide in phencyclidine-induced place aversion and preference in mice  

Microsoft Academic Search

The present study investigated the involvement of nitric oxide (NO) in phencyclidine (PCP)-induced place aversion and preference in the place conditioning paradigm. PCP-induced place aversion in naive mice was dose-dependently attenuated by administration of NG-nitro-l-arginine methyl ester (L-NAME), a NO synthase (NOS) inhibitor, during the conditioning. The NOS activity and dopamine (DA) turnover in the hippocampus in mice showing PCP-induced

Yoshiaki Miyamoto; Yukihiro Noda; Yumiko Komori; Hishayoshi Sugihara; Hiroshi Furukawa; Toshitaka Nabeshima

2000-01-01

367

Linkage of the Human Inducible Nitric Oxide Synthase Gene to Type 1 Diabetes  

Microsoft Academic Search

Exposure of human pancreatic islets to a mixture of cytokines induces expression of the inducible nitric oxide synthase (iNOS), impairs b-cell function, and induces apoptosis. We performed a mu- tational scanning of all 27 exons of the human NOS2 gene and linkage transmission disequilibrium testing of identified NOS2 polymor- phisms in a Danish nationwide type 1 diabetes mellitus (IDDM) family

JESPER JOHANNESEN; ANGELES PIE; FLEMMING POCIOT; OLE PETER KRISTIANSEN; ALLAN ERTMANN KARLSEN; JŘRN NERUP

2010-01-01

368

Induced nitric oxide synthase as a major player in the oncogenic transformation of inflamed tissue.  

PubMed

Nitric oxide (NO) is a free radical that is involved in the inflammatory process and carcinogenesis. There are four nitric oxide synthase enzymes involved in NO production: induced nitric oxide synthase (iNOS), endothelial NO synthase (eNOS), neural NO synthase (nNOS), and mitochondrial NOS. iNOS is an inducible and key enzyme in the inflamed tissue. Recent literatures indicate that NO as well as iNOS and eNOS can modulate cancer-related events including nitro-oxidative stress, apoptosis, cell cycle, angio-genesis, invasion, and metastasis. This chapter focuses on linking NO/iNOS/eNOS to inflammation and carcinogenesis from experimental evidence to potential targets on cancer prevention and treatment. PMID:19347276

Yang, Guang-Yu; Taboada, Sofia; Liao, Jie

2009-01-01

369

Leukaemia Inhibitory Factor Stimulates Proliferation of Olfactory Neuronal Progenitors via Inducible Nitric Oxide Synthase  

PubMed Central

Neurogenesis continues in the adult brain and in the adult olfactory epithelium. The cytokine, leukaemia inhibitory factor and nitric oxide are both known to stimulate neuronal progenitor cell proliferation in the olfactory epithelium after injury. Our aim here was to determine whether these observations are independent, specifically, whether leukaemia inhibitory factor triggers neural precursor proliferation via the inducible nitric oxide synthase pathway. We evaluated the effects of leukaemia inhibitory factor on inducible form of nitric oxide synthase (iNOS) expression, and cell proliferation in olfactory epithelial cell cultures and olfactory neurosphere-derived cells. Leukaemia inhibitory factor induced expression of iNOS and increased cell proliferation. An iNOS inhibitor and an anti-leukaemia inhibitory factor receptor blocking antibody inhibited leukaemia inhibitory factor-induced cell proliferation, an effect that was reversed by a NO donor. Altogether, the results strongly suggest that leukaemia inhibitory factor induces iNOS expression, increasing nitric oxide levels, to stimulate proliferation of olfactory neural precursor cells. This finding sheds light on neuronal regeneration occurring after injury of the olfactory epithelium.

Lopez-Arenas, Estefania; Mackay-Sim, Alan; Bacigalupo, Juan; Sulz, Lorena

2012-01-01

370

A novel potent inhibitor of inducible nitric oxide inhibitor, ONO1714, reduces intestinal ischemia–reperfusion injury in rats  

Microsoft Academic Search

The overproduction of nitric oxide (NO) by inducible nitric oxide synthase (iNOS) may contribute to the pathophysiology of intestinal injury induced by ischemia–reperfusion. The aim of the present study was to examine the effect of selective iNOS inhibition by a cyclic amidine analogue, ONO-1714, on reperfusion-induced small intestinal injury and inflammation in rats. Intestinal damage was induced in male Sprague–Dawley

Yuji Naito; Tomohisa Takagi; Hiroshi Ichikawa; Naoya Tomatsuri; Masaaki Kuroda; Yutaka Isozaki; Kazuhiro Katada; Kazuhiko Uchiyama; Satoshi Kokura; Norimasa Yoshida; Takeshi Okanoue; Toshikazu Yoshikawa

2004-01-01

371

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

372

Role of a cytokine-inducible nitric oxide synthase in the control of myocardial contractile state  

Microsoft Academic Search

Nitric oxide (NO) is a nearly ubiquitous intercellular and intracellular chemical messenger produced by a family of enzymes collectively called NO synthases. Evidence from several laboratories documented the expression of the inducible NO synthase, or NOS2, within several cellular constituents of ventricular muscle, including cardiac myocytes, after exposure to inflammatory cytokines in vitro or in vivo. Cardiac microvascular endothelial cells,

Jean-Luc Balligandl; Dan Ungureanu-Longrois; Thomas W. Smith

1996-01-01

373

Role of Inducible Nitric Oxide Synthase in Pharmacological “Preconditioning” with Monophosphoryl Lipid A  

Microsoft Academic Search

Pretreatment with monophosphoryl lipid A (MLA) can pharmacologically mimic the second window of ischemic preconditioning (SWOP) to protect the heart from prolonged ischemia and reperfusion injury. Based on the delayed time course for development of MLA associated cardioprotection, this study was designed to test if MLA's cardioprotective effect is mediated by signalling through production of inducible nitric oxide synthase (iNOS),

Lin Zhao; Patricia A. Weber; Jerry R. Smith; Malissa L. Comerford; Gary T. Elliott

1997-01-01

374

Inducible Nitric Oxide Synthase Gene Expression in Brain Following Cerebral Ischemia  

Microsoft Academic Search

Summary: Cerebral ischemia is followed by a local inflammatory response that is thought to participate in the extension of the tissue damage occurring in the postischemic period. However, the mechanisms whereby the inflammation contributes to the progression of the damage have not been fully elucidated. In models of inflammation, expression of the inducible isoform of nitric oxide synthase (iNOS) is

Costantino Iadecola; Fangyi Zhang; Sherry Xu; Robyn Casey; M. Elizabeth Ross

1995-01-01

375

Role of inducible nitric oxide synthase expression in aberrant crypt foci-adenoma-carcinoma sequence  

Microsoft Academic Search

AIM: To investigate the expression of inducible nitric oxide synthase (iNOS) in aberrant crypt foci (ACF) -adenoma- carcinoma sequence and its relation with tumor cell apoptosis, proliferation and angiogenesis. METHODS: The expression of iNOS, proliferating cell nuclear antigen (PCNA) and microvessel density (MVD) in different stages of colorectal cancer were studied by immunohistochemical method from 30 normal tissues, 30 nonhyperplastic

Mei-Hua Xu; Chang-Sheng Deng; You-Qing Zhu; Jun Lin

2003-01-01

376

An Unprocessed Pseudogene of Inducible Nitric Oxide Synthase Gene in Human  

Microsoft Academic Search

Inducible nitric oxide synthase (iNOS or NOSII) is one of three distinct NOS isoforms in human. The NOSII isoform is expressed in a variety of cells and tissues in response to endotoxins and cytokines. The human genome contains at least two loci for the NOSII gene, one of which (NOSII-1) has previously been assigned to proximal region of the long

Chang-Shin Park; Hyun-Sil Lee; Hei-Yung Lee; Gopal Krishna

1997-01-01

377

Characterization of Human Liver Inducible Nitric Oxide Synthase Expressed in Escherichia coli  

Microsoft Academic Search

We have cloned the human liver inducible isoform of nitric oxide synthase (NOS) into anEscherichia coliexpression vector and have expressed and purified the enzyme. The protein has been expressed with and without a polyhistidine tail. In both cases, expression of functional protein requires coexpression with calmodulin and inclusion of tetrahydrobiopterin (H4B) in the purification buffers. Unlike the constitutive isoforms of

Nancy Counts Gerber; Clinton R. Nishida; Paul R. Ortiz de Montellano

1997-01-01

378

Expression of inducible nitric oxide synthase in macrophages and smooth muscle cells in various types of human atherosclerotic lesions  

Microsoft Academic Search

Nitric oxide (NO) is an important regulatory agent in blood vessels. We studied the expression of inducible nitric oxide\\u000a synthase (iNOS) in different types of human atherosclerotic lesions using simultaneous in situ hybridization and immunocytochemistry.\\u000a Since nitric oxide and its derivates or reaction products can have both oxidative and antioxidative effects, we also studied\\u000a the presence of oxidized low-density lipoproteins

Jukka S. Luoma; S. Ylä-Herttuala

1999-01-01

379

In vitro inducible nitric oxide synthesis inhibitory active constituents from Fraxinus rhynchophylla.  

PubMed

Bioassay-guided fractionation of an H2O extract of the barks of Fraxinus rhynchophylla has furnished two inducible nitric oxide synthase (iNOS) inhibitory compounds, ferulaldehyde (1) and scopoletin (3) together with a coumarin, fraxidin (2). Compounds 1 and 3 showed inhibition of nitric oxide (NO) synthesis in a dose-dependent manner by murine macrophage-like RAW 264.7 cells stimulated with interferon-gamma (IFN-gamma) plus lipopolysaccharide (LPS). The inhibition of NO synthesis of 1 was reflected in the decreased amount of iNOS protein, as determined by Western blotting. PMID:10575381

Kim, N Y; Pae, H O; Ko, Y S; Yoo, J C; Choi, B M; Jun, C D; Chung, H T; Inagaki, M; Higuchi, R; Kim, Y C

1999-10-01

380

S-Nitrosation of arginase 1 requires direct interaction with inducible nitric oxide synthase  

PubMed Central

Arginase constrains endothelial nitric oxide synthase activity by competing for the common substrate, L-Arginine. We have recently shown that inducible nitric oxide synthase (NOS2) S-nitrosates and activates arginase 1 (Arg1) leading to age-associated vascular dysfunction. Here, we demonstrate that a direct interaction of Arg1 with NOS2 is necessary for its S-nitrosation. The specific domain of NOS2 that mediates this interaction is identified. Disruption of this interaction in human aortic endothelial cells prevents Arg1 S-nitrosation and activation. Thus, disruption of NOS2–Arg1 interaction may represent a therapeutic strategy to attenuate age related vascular endothelial dysfunction.

Dunn, Jessilyn; Gutbrod, Sarah; Webb, Alanah; Pak, Alina; Jandu, Simran K.; Bhunia, Anil; Berkowitz, Dan E.

2013-01-01

381

Effects of heme oxygenase-1 on bacterial antigen-induced articular chondrocyte catabolism in vitro.  

PubMed

This study tested the hypothesis that heme oxygenase-1 (HO-1) expression counteracts bacterial antigen-induced catabolic metabolism in human articular chondrocytes. HO-1 expression was induced in chondrocytes by the iron-containing porphoryin, hemin. Anti-catabolic and anti-apoptotic effects of HO-1 expression were evaluated following bacterial antigen (lipopolysaccharides, LPS) activation of chondrocytes by quantification of cytokine and cartilage matrix protein expression. Effects of HO-1 over-expression on chondrocyte matrix metabolism were evaluated using plasmid-driven protein synthesis. Hemin increased HO-1 expression and LPS increased interleukin-1beta and interleukin-6 gene and protein expression in chondrocytes. Hemin-induced HO-1 decreased LPS-induced interleukin-1beta and interleukin-6 gene and protein expression. Increased HO-1 expression partially reversed LPS-suppression of aggrecan and type II collagen gene expression and suppressed LPS-induced gene expression of IL-6, inducible nitric oxide synthase (iNOS), matrix metalloproteinases (MMPs), and IL-1beta. HO-1 induction was inversely correlated with LPS-induced chondrocyte apoptosis. HO-1 over-expression in chondrocytes decreased matrix protein gene expression. With LPS activation, increased HO-1 expression decreased chondrocyte catabolism, partially reversed LPS-dependent inhibition of cartilage matrix protein expression and protected against apoptosis. Without LPS, hemin-induced HO-1 and plasmid-based over-expression of HO-1 inhibited cartilage matrix gene expression. The results suggest that elevated HO-1 expression in chondrocytes is protective of cartilage in inflamed joints but may otherwise suppress matrix turn over. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31:1943-1949, 2013. PMID:24038461

Mawatari, Taro; Nakamichi, Ikuo; Suenaga, Eiji; Maloney, William J; Smith, Robert L

2013-08-22

382

The role of cytokines and inducible nitric oxide synthase in endotoxemia-induced endothelial dysfunction.  

PubMed

Sepsis is characterized by a blunted vascular responses due to impairment of endothelial function. The aim of our study was to assess endothelial function and the role of cytokines and nitric oxide (NO). Endotoxin tolerance was induced in 14 healthy volunteers by intravenous injection of 2 ng.kg.d lipopolysaccharide on 5 consecutive days. Forearm blood flow (FBF) was measured by strain-gauge plethysmography during dose-response curves of endothelium-dependent vasodilator acetylcholine and endothelium-independent vasodilator sodium nitroprusside before and 4 hours after LPS administration on days 1 and 5. In another study, 7 healthy volunteers were given selective inducible NO synthase inhibitor aminoguanidine intravenous continuously from 1 hour after a single LPS administration until 5 hours. FBF showed an attenuation of ACh-induced vasodilatory response with 67% (45%-72%) 4 hours after the first LPS administration (P = 0.01) with an unchanged dose-response curve to sodium nitroprusside. This attenuation to ACh infusion did not occur in the presence of aminoguanidine (P = 0.21) and also did not occur when tolerance was present on day 5 (P = 0.45). Our data demonstrate that endothelial dysfunction caused by endotoxemia does not occur when endotoxin tolerance develops, indicated by the absence of cytokine production and during administration of selective inducible NO synthase inhibitor aminoguanidine in vivo. PMID:20224425

Draisma, Annelies; Dorresteijn, Mirrin J; Bouw, Martijn P; van der Hoeven, Johannes G; Pickkers, Peter

2010-06-01

383

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

2011-12-31

384

Nitric oxide decreases cytokine-induced endothelial activation. Nitric oxide selectively reduces endothelial expression of adhesion molecules and proinflammatory cytokines.  

PubMed

To test the hypothesis that nitric oxide (NO) limits endothelial activation, we treated cytokine-stimulated human saphenous vein endothelial cells with several NO donors and assessed their effects on the inducible expression of vascular cell adhesion molecule-1 (VCAM-1). In a concentration-dependent manner, NO inhibited interleukin (IL)-1 alpha-stimulated VCAM-1 expression by 35-55% as determined by cell surface enzyme immunoassays and flow cytometry. This inhibition was paralleled by reduced monocyte adhesion to endothelial monolayers in nonstatic assays, was unaffected by cGMP analogues, and was quantitatively similar after stimulation by either IL-1 alpha, IL-1 beta, IL-4, tumor necrosis factor (TNF alpha), or bacterial lipopolysaccharide. NO also decreased the endothelial expression of other leukocyte adhesion molecules (E-selectin and to a lesser extent, intercellular adhesion molecule-1) and secretable cytokines (IL-6 and IL-8). Inhibition of endogenous NO production by L-N-monomethyl-arginine also induced the expression of VCAM-1, but did not augment cytokine-induced VCAM-1 expression. Nuclear run-on assays, transfection studies using various VCAM-1 promoter reporter gene constructs, and electrophoretic mobility shift assays indicated that NO represses VCAM-1 gene transcription, in part, by inhibiting NF-kappa B. We propose that NO's ability to limit endothelial activation and inhibit monocyte adhesion may contribute to some of its antiatherogenic and antiinflammatory properties within the vessel wall. PMID:7542286

De Caterina, R; Libby, P; Peng, H B; Thannickal, V J; Rajavashisth, T B; Gimbrone, M A; Shin, W S; Liao, J K

1995-07-01

385

Streptococcus anginosus induced nitric oxide synthesis by murine peritoneal macrophages without help of IFN?  

Microsoft Academic Search

Streptococcus anginosus-induced nitric oxide (NO) synthesis of murine peritoneal exudate cells (PEC) was assessed. A bioactive antigen (SAA) from S. anginosus induced macrophages in PEC exclusively to produce NO, which was not affected by the addition of IFN?. After stimulation with SAA, phosphorylation of both p38 and ERK1\\/2 mitogen-activated protein kinase (MAPK) was observed. However, a p38, but not ERK1\\/2,

C. Yamaura; M. Sasaki; Y. Ohara-Nemoto; S. Tajika; Y. Shimoyama; S. Kimura

2005-01-01