• Title/Summary/Keyword: iNOS inhibitor

Search Result 199, Processing Time 0.029 seconds

Inhibitory Activity of Chinese Medicinal Plants on Nitric Oxide Synthesis in Lipopolysaccharide -Activated Macrophages

  • Ryu, Jae-Ha;Ahn, Han-Na;Lee, Hwa-Jin;Feng, Li;Qun, Wen-He;Han, Yong-Nam;Han, Byung-Hoon
    • Biomolecules & Therapeutics
    • /
    • v.9 no.3
    • /
    • pp.183-187
    • /
    • 2001
  • Nitric oxide (NO) produced in large amounts by the inducible nitric oxide synthase (iNOS) is known to be responsible for the vasodilation and hypotension observed in septic shock and inflammation. The inhibitors of iNOS, thus, may be useful candidate for the treatment of inflammatory diseases accompanied by the overproduction of NO. We prepared alcoholic extracts of Chinese medicinal plants and screened their inhibitory activity against NO production in lipopolysaccharide (LPS)-activated macrophages. Among the 80 kinds of extracts of herbal drugs, 15 extracts showed potent inhibitory activity of NO production above 80% at the concentration o$50\mu\textrm{g}/ml$. These potent extracts showed dose dependent inhibition of NO production of LPS-activated macrophages at the concentration of 50, 30,$10\mu\textrm{g}/ml$. Especially, Rhus chinensis, Senecio scandens and Wikstroemia indica showed most potent inhibition above 50% at the concentration of $10\mu\textrm{g}/ml$. These plants are promising candidates for the study of the activity-guided purification of active compounds and would be useful for the treatment of inflammatory diseases and endotoxemia accompanying the overproduction of NO.

  • PDF

Tribulus terrestris Suppresses the Lipopolysaccharide-Induced Inflammatory Reaction in RAW264.7 Macrophages through Heme Oxygenase-1 Expressions

  • Kim, Jai Eun
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.28 no.1
    • /
    • pp.63-68
    • /
    • 2014
  • The fruit of Tribulus terrestris L. (Zygophyllaceae) is an important source of traditional Korean and Chinese medicines. In this study, NNMBS223, consisting of the ethanol extract of T. terrestris, showed potent anti-inflammatory activities in RAW264.7 macrophages. We investigated the effect of NNMBS223 in suppressing the protein expression of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2 and production of iNOS-derived nitric oxide (NO), COX-2-derived prostaglandin E2 (PGE2) in lipopolysaccharide (LPS)-stimulated macrophages. In addition, NNMBS223 induced expression of heme oxygenase (HO)-1 through nuclear translocation of nuclear factor E2-related factor 2 (Nrf2) in macrophages. The effects of NNMBS223 on LPS-induced production of NO and PGE2 were partially reversed by the HO activity inhibitor tin protoporphyrin (SnPP). These findings suggest that Nrf2-dependent increases in expression of HO-1 induced by NNMBS223 conferred anti-inflammatory activities in LPS stimulated RAW264.7 macrophages.

Role of NO in Activation of $NF{\kappa}B$ by PM2.5 in Lung Epithelial Cells (PM2.5로 자극한 폐상피세포의 $NF{\kappa}B$ 활성화에 NO의 역할)

  • Kim, Kyoung-Ah;Nam, Hae-Yun;Mun, Je-Hyeok;Jeong, Jin-Sook;Lim, Young;Kai, Hirofumi
    • Tuberculosis and Respiratory Diseases
    • /
    • v.52 no.6
    • /
    • pp.616-626
    • /
    • 2002
  • Background : The present study was performed to further improve our understanding of molecular mechanisms involved in the activation of NFkB, a major transcriptional factor involved in the inflammatory response in the lung, by particulate matter in lung epithelial cells with an aerodynamic diameter of less than $2.5{\mu}m$(PM2.5). Materials and Methods : Immediate production of reactive oxygen species (ROS) and nitrogen species (RNS), with the PM2.5 induced expression of inducible nitric oxide synthase (iNOS), $I{\kappa}B$ degradation and $NF{\kappa}B$-dependent transcriptional activity, in 549 cells, were monitored. Addition, we also examined the effect of the iNOS inhibitor, L-N6-(1-iminoethyl) lysine hydrochloride (L-NIL), on the PM2.5-induced $NF{\kappa}B$ activation in A549 cells. Results : The rapid degradation of $I{\kappa}B$ and the increase of transcriptional activity of the $NF{\kappa}B$-dependent promotor were observed in A549 cells exposed to PM2.5. The immediate production of ROS in response to PM2.5 in A549 cells was not clearly detected, although immediate responses were observed in RAW264.7 cells. A 549 cells, cultured in the presence of PM2.5, produced an increase in NO, which was noticeably significant after 15 min of exposure with the expression of iNOS mRNA. The addition of L-NIL, an iNOS inhibitor, significantly inhibited the PM2.5-induced $I{\kappa}B$ degradation and the increase of the $NF{\kappa}B$-dependent transcriptional activity. Conclusion : These results suggest that PM2.5 stimulates the immediate production of RNS, leading to the activation of $NF{\kappa}B$ in the pulmonary epithelium.

Effect of Triacsin C on LPS-induced Inflammation in 3T3-L1 Adipocytes (LPS에 의해 유도된 3T3-L1 지방세포의 염증반응에 대한 Triacsin C의 효과)

  • Park, Eun-Ju;Spurlock, Michael
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.41 no.2
    • /
    • pp.283-288
    • /
    • 2012
  • Triacsin C, an inhibitor of acyl-CoA synthetase, is known to have antiatherosclerotic and vasodilatory activities. The aims of this study were to evaluate the effects of triacsin C on endotoxin-induced (lipopolysaccharide, LPS) inflammation in 3T3-L1 adipocytes and also to evaluate its synergistic effect with triacsin C and resveratrol, a potent antiinflammatory agent. Exposure to LPS for 18 hr increased secretion of IL-6 into the culture medium and mRNA expression of IL-6, MCP-1, TLR and iNOS. Pretreatment of triacsin C for 2 hr suppressed IL-6 accumulation in the medium and the induction of IL-6 expression by LPS, which was more effective than resveratrol treatment. The synergistic effect of triacsin C and resveratrol was found to reduce the expression of iNOS by LPS. However, neither triacsin C nor resveratrol affected the LPS-induced expression of MCP-1, TLR or iNOS. These findings indicate that triacsin C may be a local regulator of inflammation in the adipocyte, although detailed mechanisms are needed to elucidate this through further research.

The Effects of Chelidonium majus on NO and $TNF-{\alpha}$ Production in Macrophages (백굴채가 대식세포의 NO 및 $TNF-{\alpha}$ 생성에 미치는 영향)

  • 김홍준;문석재;김동웅;문구;원경숙;윤준철;김유경;원진희
    • The Journal of Korean Medicine
    • /
    • v.24 no.2
    • /
    • pp.138-147
    • /
    • 2003
  • Objectives : In this study, we investigated the mechanism by which Chelidonium majus (CM) regulates nitric oxide (NO) production. Methods : Using mouse peritoneal macrophages, the mechanism by which CM regulates NO or tumor necrosis $factor-{\alpha}(TNF-{\alpha})$ production was examined. NO release was measured by the Griess method. $TNF-{\alpha}$ production was measured by the ELISA method. The protein extracts were prepared and samples were analyzed for the inducible NOS(iNOS) expression and nuclear factor kappa $B(NF-{\kappa}B)$ activation by Western blotting. Results : When CM was used in combination with recombinant $interferon-{\gamma}{\;}(rIFN-{\gamma})$, there was a marked cooperative induction of NO production. CM had an effect on NO production by itself. The expression of the iNOS gene was increased in $rIFN-{\gamma}$ plus CM-stimulated peritoneal macrophages and almost completely inhibited by pre-treatment with pyrrolidine dithiocarbamate (PDTC), an inhibitor of $NF-{\kappa}B$. The $NF-{\kappa}B$ activation was increased in rIFN-{\gamma} plus CM-induced peritoneal macrophages. The increased production of NO from $rIFN-{\gamma}$ plus CM-stimulated peritoneal rnacrophages was decreased by the treatment with $N^{G}-monomethyl-{_L}-arginine{\;}(N^{G}MMA){\;}N^{\alpha}-Tosyl-Phe$ chloromethyl ketone (TPCK) , and was almost completely inhibited by pre-treatment with PDTC. Furthermore, treatment with CM alone or rIFN-{\gamma} plus CM in peritoneal macrophages caused a significant increase in $TNF-{\alpha}$ production. PDTC decreased CM-induced $TNF-{\alpha}$ production significantly. After CM treatment in HT-29 or AGS cells, cell viability decreased. Conclusions : These findings demonstrate that CM increases the production of NO and $TNF-{\alpha}{\;}by{\;}rIFN-{\gamma}-primed$ macrophages and suggest that NF-B plays a critical role in mediating these effects of CM.

  • PDF

Cardiovascular Responses and Nitric Oxide Production in Cerebral Ischemic Rats

  • Shinl, Chang-Yell;Lee, Nam-In;Je, Hyun-Dong;Kim, Jeong-Soo;Sung, Ji-Hyun;Kim, Dong-Seok;Lee, Doo-Won;Bae, Ki-Lyong;Sohn, Uy-Dong
    • Archives of Pharmacal Research
    • /
    • v.25 no.5
    • /
    • pp.697-703
    • /
    • 2002
  • We investigated that the role of nitric oxide (NO) on ischemic rats in brain and heart. Ischemia was induced by both common carotid arteries (CCA) occlusion for 24h following reperfusion. Then tissue samples were removed and measured NOx. In brain, NOx was increased by about 40% vs. normal and it was significantly inhibited by aminoguanidine, selective iNOS inhibitor. This result showed that NOx concentration was increased by iNOS. We investigated the role of $Ca^{2+}$ during ischemia. Nimodipine, L-type calcium channel blocker, didn't inhibit the increases of NOx concentration during ischemia. It suggested that increased NOx was due to calcium-independent NOS. MK-801, which N-methyl-D-aspartate (NMDA) receptor antagonist, didn't significantly prevent the increases of NOx. In heart, ischemia caused NOx decrease and it is inconsistent with NOx increase in brain. Aminoguanidine and nimodipine didnt affect on NOx decrease. But MK-801 more lowered NOx concentration than those of ischemia control group. It seemed that $Ca^{2+}$ influx in heart partially occurred via NMDA receptor and inhibited by NMDA receptor antagonist. The mean arterial pressure (MAP) in ischemic rats after 24h of CCA occlusion was decreased when compared to normal value, whereas the heart rates (HR) was not different between two groups. Aminoguanidine or MK801 had no effect on MAP or HR, but nimodipine reduced MAP. There was no difference the effects of aminoguanidine, nimodipine, or MK-801, on MAP and HR between normal rats and ischemic rats. In summary, ischemic model caused an increase of NOx concentration, suggesting that this may be produced via iNOS, which is calcium independent in brain. However in heart, ischemia decreased NOx concentration and NMDA receptor was partially involved. The basal MAP was decreased in ischemic rats but HR was not different from normal control, suggesting that increased NOx in brain of ischemic rat may result in the hypotension.

Coupling Efficiencies of m1, m3 and m5 Muscarinic Receptors to the Stimulation of Neuronal Nitric Oxide Synthase

  • Park, Sun-Hye;Lee, Seok-Yong;Cho, Tai-Soon
    • Proceedings of the Korean Society of Applied Pharmacology
    • /
    • 1996.04a
    • /
    • pp.207-207
    • /
    • 1996
  • Through molecular cloning, five muscarinic receptors have been identified. The muscarinic receptors can be generally grouped according to their coupling to either stimulation of phospholipase C (m1, m3, and m5) or the inhibition of adenylate cyclase (m2 and m4). Each m1, m3, and m5 receptors has the additional potential to couple to the activation of phospholipase A$_2$, C, and D, tyrosine kinase, and the mobilization of Ca$\^$2+/. However, the differences in coupling efficiencies to different second messenger systems between these receptors have not been studied well. Ectopic expression of each of these receptors in mammalian cells has provided the opportunity to evaluate the signal transduction of each in some detail. In this work we compared the coupling efficiencies of the m1, m3 and m5 muscarinic receptors expressed in chinese hamster ovary (CHO) cells to the Ca$\^$2+/ mobilization and the stimulation of neuronal nitric oxide synthase (nNOS). Because G protein/PLC/PI turnover/[(Ca$\^$2+/])i/NOS pathway was supposed as a main pathway for the production of nitric oxide via muscarinic receptors, we studied on ml, m3 and m5 receptors. Stimulation of guanylate cyclase activity in detector neuroblastoma cells was used as an index of generation nitric oxide (NO) in CHO cells. The agonist carbachol increased the cGMP formation and the intracellular [Ca$\^$2+/] in concentration dependent manner in three types of receptors and the increased cGMP formation was significantly attenuated by scavenger of NO or inhibitor of NOS. m5 receptors was most efficiently coupled to stimulation of nNOS, And, the coupling efficiencies to the stimulation of neuronal nitric oxide synthase in three types of receptors were parallel with them to the Ca$\^$2+/ mobilization.

  • PDF

Anti-inflammatory Effects of Ethanolic Extracts from Codium fragile on LPS-Stimulated RAW 264.7 Macrophages via Nuclear Factor kappaB Inactivation

  • Yoon, Ho-Dong;Jeong, Eun-Ji;Choi, Ji-Woong;Lee, Min-Sup;Park, Myoung-Ae;Yoon, Na-Young;Kim, Yeon-Kye;Cho, Deuk-Moon;Kim, Jae-Il;Kim, Hyeung-Rak
    • Fisheries and Aquatic Sciences
    • /
    • v.14 no.4
    • /
    • pp.267-274
    • /
    • 2011
  • Bacterial lipopolysaccharide (LPS) induces expression of pro-inflammatory cytokines and enzymes producing nitric oxide (NO) and prostaglandins (PGs) in immune cells. This process is mediated by the activation of nuclear factor kappaB (NF-${\kappa}B$). In this study, we investigated the anti-inflammatory characteristics of Codium fragile ethanolic extract (CFE) mediated by the regulation of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) using LPS-stimulated murine macrophage RAW 264.7 cells. CFE significantly inhibited LPS-induced NO and $PGE_2$ production in a dose-dependent manner and suppressed the expression of iNOS and COX-2 proteins in LPS-stimulated RAW 264.7 cells with no cytotoxicity. Pro-inflammatory cytokines, such as interleukin (IL)-$1{\beta}$, IL-6, and tumor necrosis factor-${\alpha}$, were significantly reduced by treatment of CFE in LPS-stimulated RAW 264.7 cells. CFE inhibited the promoter activity of (NF)-${\kappa}B$ in LPS-stimulated macrophages. Treatment with CFE suppressed translocation of the NF-${\kappa}B$ p65 subunit by preventing proteolytic degradation of inhibitor of ${\kappa}B-{\alpha}$. These results indicate that the CFE-mediated inhibition of NO and $PGE_2$ production in LPS-stimulated RAW 264.7 cells is mediated through the NF-${\kappa}B$-dependent transcriptional downregulation of iNOS and COX-2, suggesting the potential of CFE as a nutraceutical with anti-inflammatory activity.

Citrus platymamma inhibits the expression of pro-inflammatory cytokines, inducible nitric oxide synthase, and cyclooxygenase-2 in RAW264.7 macrophage (RAW264.7 대식세포에서 Citrus platymamma의 iNOS, COX-2, 염증성 사이토카인 발현 억제 효과)

  • Kim, Sang Suk;Park, Kyung Jin;An, Hyun Joo;Choi, Young Hun
    • Food Science and Preservation
    • /
    • v.23 no.7
    • /
    • pp.1026-1032
    • /
    • 2016
  • Citrus platymamma hort. ex Tanaka is widely used in traditional Korean medicine because of its medicinal benefits including an anti-inflammatory effect. This study aimed to evaluate changes in the flavonoid content and anti-inflammatory activities of C. platymamma during its harvest period. Fruit peel samples were obtained between September 2015 and February 2016. The results indicate that C. platymamma peel extract (CPE) was an effective inhibitor of lipopolysaccharide (LPS)-induced NO production in RAW264.7 cells. The inhibitory effects of CPE at $100{\mu}g/mL$ concentration included dose-dependent decreases in the expression of iNOS and COX-2 proteins. In addition, CPE decreased the expression of pro-inflammatory cytokines TNF-${\alpha}$, IL-$1{\beta}$, and IL-6. The highest anti-inflammatory activity and flavonoid content were observed in CPE of C. platymamma peel harvested during the immature fruit period in September. Further, to assess the suitability of CPE for cosmetic use, we performed MTT assays using HaCaT keratinocytes and observed that CPE did not exhibit any cytotoxicity. To test the potential application of CPE as a cosmetic material, we also performed primary skin irritation tests on normal skin of 30 volunteers and no adverse reactions were observed. The results of this study indicate that CPE may be considered as an anti-inflammatory candidate for inclusion in cosmetic materials.

A study on the regulatory effect of p-38 MAP kinase on nitric oxide and interleukin-6 in osteoblasts (조골세포에시 p-38 MAP kinase의 nitric oxide 및 interleukin-6 생성조절에 관한 연구)

  • Lee, Kyung-Won;Lee, Doe-Hoon;Kang, Kyung-Hwa;Kim, Sang-Cheol
    • The korean journal of orthodontics
    • /
    • v.33 no.3 s.98
    • /
    • pp.199-210
    • /
    • 2003
  • Tooth movement is the result of bone metabolism in the periodontium, where various cytokines take important roles. Interleukin-6(II-6) and nitrous oxide (NO) were reported to be secreted from osteoblasts in the process of bone resorption. The mechanism of the process has not been clearly understood, but the activation of mitogen-activated protein kinase (MAPK) was known to be an important process in the release of the inflammatory cytotines in macrophages. In this regard, to prove the role of MAPK in the release of IL-6 and NO in MC3T3E-1 osteoblasts, Northern blot analysis, Western blot analysis and immune complex kinase assay were used. As a result, the treatment of MC3T3E-1 osteoblast cultures with combined $interferon-\gamma(IFN-\gamma)$, lipopolysaccharide (LPS) and tumor necrosis $factor-\alpha(TNF-\alpha)$ induces expressions of inducible nitric oxide synthase (iNOS) and IL-6, resulting in sustained releases of large amounts of NO and IL-6. However, $IFN-\gamma,\;LPS,\;and\;TNF-\alpha$ individually induce a non-detectable or small amount of NO and IL-6 in MC3T3E-1 osteoblasts. The role of MAPK activation in the early intracellular signal transduction involved in iNOS and IL-6 transcription in the combined agents-stimulated osteoblasts has been investigated. The p38 MAPK pathway is specifically involved in the combined agents-induced NO and IL-6 release, since NO and IL-6 release in the presence of a specific inhibitor of p38 MAPK, 4-(4-fluorophenyl)-2-(4-metylsulfinylphenyl)-5-(4-metylsulfinylphenyl)-5-(4-pyridyl)imidazole) (SB203580), were significantly diminished. In contrast, PD98059, a specific inhibitor of MEK1, had no effect on NO and IL-6 release. Northern blot analysis showed that the p3a MAPK pathway controlled the iNOS and IL-6 transcription level. These data suggest that p38 MAPK play an important role in the secretion of NO and IL-6 in $LPS/IFN{\gamma}-or\;TNF-\gamma-treated\;MC3T3E-1$ osteoblasts.