• Title/Summary/Keyword: Nos2

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Inducible Nitric Oxide Synthase mRNA Expression and Nitric Oxide Production in Silica-Induced Acute Inflammatory Lung Injury

  • Lee, Ji-Hee
    • The Korean Journal of Physiology and Pharmacology
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    • v.2 no.2
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    • pp.233-239
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    • 1998
  • Stimulated alveolar macrophages and neutrophils produce nitric oxide, a free radical by an inducible nitric oxide synthase(iNOS), which reacts with superoxide anion to form peroxynitrite, a more highly reactive toxic species. The objectives of the present study were to evaluate acute inflammatory lung injury and to determine iNOS mRNA induction and nitric oxide production by rat broncho-alveolar lavage cells following intratracheal treatment of silica. After 4 h exposure to silica, differential counts of broncho-alveolar lavage cells and lactate dehydrogenase(LDH) activity as well as total protein in the broncho-alveolar lavage fluid were determined. Broncho-alveolar lavage cells were also assayed for iNOS mRNA and the productions of nitrite and nitrate measured in the cells cultured. Differential analysis of broncho-alveolar lavage cells showed that the number of alveolar macrophages slightly decreased following silica treatment; however, red blood cells, lymphocytes, and neutrophils significantly were increased by 9-, 14-, and 119-fold following silica treatment, respectively, compared with the saline control. It was also found significant increases in the LDH activity and total protein in the lavage fluid obtained from silica-treated rats, indicating silica-induced acute lung injury. Northern blot analysis demonstrated that the steady state levels of iNOS mRNA in broncho-alveolar lavage cells were increased following silica treatment. The productions of nitrite and nitrate in the cultured cells were significantly increased by 2-fold following silica treatment, respectively, which were attenuated by the NOS inhibitor $N{\omega}-nitro-L-arginine-methyl$ ester(L-NAME) and partially reversed by L-arginine. These findings suggest that nitric oxide production in alveolar macrophages and recruited neutrophils is increased in response to silica. Nitric oxide may contribute in part to acute inflammatory lung injury.

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Antioxidant Effects and Anti-inflammation Effects of Lophatheri Herba Water Extracts Via Reducing iNOS Synthesis Induced by LPS in RAW 264.7 Cell (담죽엽의 항산화 효과와 RAW 264.7 세포에서 LPS로 유도된 iNOS 발현에 미치는 영향)

  • Hwang, Sung-Yeoun;Lee, Sung-Won;Kwon, Kang-Beom;Choi, Won-Jong;Kim, Jae-Hyo;Ahn, Seong-Hun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.24 no.6
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    • pp.976-982
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    • 2010
  • We studied to know the anti-inflammation effect on water extracts of Lophatheri Herba which was growing in every places in our country. We objected free radical scanvenger effect and nitrite eliminate effect of the Lophatheri Herba water extracts, and the cell viabillity, the effects of Lophatheri Herba water extracts on NO production, iNOS synthesis induced by LPS. Free radical scavenger effects were $27.91{\pm}0.12%$, $38.96{\pm}0.10%$, $46.22{\pm}0.15%$ depend on 0.5, 1.0, 2.0 mg/ml each dose of Lophatheri Herba water extracts. Nitrite eliminate effects were $9.86{\pm}0.3%$, $80.61{\pm}0.23%$, $97.62{\pm}0.56%$ in 0.1, 1.0, 2.0 mg/ml Lophatheri Herba water extracts on pH 1.2. NO production and iNOS synthesis induced by LPS were reduced in RAW 264.7 cell by Lophatheri Herba water extracts. As the above results, Lophatheri Herba water extracts have anti-inflammation effects via NO production decrease, iNOS synthesis decrease mechanism. So Lophatheri Herba water extracts will be used as the protection or treatment in chronic inflammation desease like a asthma, stomatitis etc.

Inhibitory Effect of Galangin from Alpinia officinarum on Lipopolysaccharide-induced Nitric Oxide Synthesis in RAW 264.7 macrophages (고량강으로부터 분리된 galangin의 RAW 264.7 세포주에서 LPS로 유도된 nitric oxide 생성 저해활성)

  • Lee, Hwa Jin
    • Korean Journal of Food Science and Technology
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    • v.46 no.4
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    • pp.511-515
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    • 2014
  • In a screen for plant-derived inhibitors of nitric oxide (NO) production in lipopolysaccharide (LPS)-activated RAW 264.7 macrophage cells, a flavonol isolated from the chloroform extract of Alpinia officinarum was isolated. The structure of the flavonol was found to be 3,5,7-trihydroxy-2-phenylchromen-4-one (galangin, GLG) by using spectroscopy. GLG exhibited an inhibitory effect ($IC_{50}$ value: $26.8{\mu}M$) on NO production in LPS-stimulated RAW 264.7 murine macrophage cells. Moreover, GLG suppressed expressions of inducible nitric oxide synthase (iNOS) protein and mRNA in a dose-dependent manner.

Mechanisms of Siegesbeckia Glabrescens-induced Smooth Muscle Cell Apoptosis: Role of iNOS and PKC${\alpha}$ (희첨의 iNOS 발현과 PKC${\alpha}$ 억제를 통한 혈관평활근세포의 apoptosis 유도)

  • Lee, Seung-Yeul;Jun, Soo-Young;Kim, Jong-Bong;Jang, Hyo-Oil;Kim, Gil-Whon;Shin, Heung-Mook
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.20 no.5
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    • pp.1233-1240
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    • 2006
  • We have recently demonstrated that Siegesbeckia glabrescens(SG), a herbal medicine, induces apoptosis via nitric oxide(NO) production in human aortic smooth muscle cells(HASMCS). However, the molecular pathways involved in SG-mediated apoptosis are not fully understand. In the present study, we investigated the cellular mechanisms of SG-induced apoptosis in HASMCS. SG induced NO production through inducible nitric oxide synthase(iNOS) induction. The apoptotic effect of SG was attenuated by L-NNA, a NOS inhibitor. In the presence of L-NNA, the degradation of procaspase-3 by SG was inhibited. SG treatment induced a decrease in Bcl-2 expression but did not affect the expression of Bax. In addition, SG treatment evoked both down-regulation of PKC ${\alpha}$ and inhibition of PKC ${\alpha}$ phosphorylation. These downregulations were reversed by addition of L-NNA. It seems likely to De a downregulation of PKC${\alpha}$ due to long term treatment with PMA. Taken together, these results suggest that apoptotic effects of SG may be due to NO production via iNOS mRNA expression. Furthermore, Bcl-2 and PKC${\alpha}$ downregulation, and caspase-3 activation may be involved in the mechanisms for apoptotic effects by SG.

Inhibition of LPS induced iNOS, COX-2 and cytokines expression by kaempferol-3-O-${\beta}$-D-sophoroside through the $NF{-\kappa}B$ inactivation in RAW 264.7 cells (Kaempferol-3-O-${\beta}$-D-sophoroside의 RAW 264.7 세포에서 $NF{-\kappa}B$ 억제를 통한 LPS에 의해 유도되는 iNOS, COX-2 및 cytokine들의 발현 저해효과)

  • Park, Seung-Jae;Shin, Ji-Sun;Cho, Woong;Cho, Young-Wuk;Ahn, Eun-Mi;Baek, Nam-In;Lee, Kyung-Tae
    • Korean Journal of Pharmacognosy
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    • v.39 no.2
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    • pp.95-103
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    • 2008
  • In the present study, we investigated the anti-inflammatory effects by kaempferol-3-O-${\beta}$-D-sophoroside (KS) isolated from Sophora japonica (Leguminosae) on the lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin ($PGE_2$) production by RAW 264.7 cell line compared with kaempferol. KS significantly inhibited the LPS-induced NO and $PGE_2$ production. Consistent with these observations, KS reduced the LPS-induced expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at the protein and mRNA levels in a concentration-dependent manner. In addition, the release and the mRNA expression levels of tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$) and interleukin-6 (IL-6) were also reduced by KS. Moreover, KS attenuated the LPS-induced activation of nuclear factor-kappa B ($NF{-\kappa}B$), a transcription factor necessary for pro-inflammatory mediators, iNOS, COX-2, $TNF-{\alpha}$ and IL-6 expression. These results suggest that the down regulation of iNOS, COX-2, $TNF-{\alpha}$, and IL-6 expression by KS are achieved by the downregulation of $NF{-\kappa}B$ activity, and that is also responsible for its anti-inflammatory effects.

Anti-inflammatory effect of seed oil of Schisandra chinensis in the LPS-treated RAW 264.7 macrophages (LPS로 자극된 Raw 264.7 대식세포에서 오미자 씨앗오일의 항염증 효과)

  • Jang, Jae-Yoon;Park, Geun-Hye
    • The Korea Journal of Herbology
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    • v.30 no.6
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    • pp.77-82
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    • 2015
  • Objectives : This study was designed to investigate of the anti-inflammatory effects of Schisandra chinensis seed oil(SSO) on the production of pro-inflammatory substances in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages.Methods : SSO was measured the production of pro-inflammatory factor (NO, PGE2, IL-1β iNOS and, COX-2) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. we used the following methods : cell viability assay, Griess reagent assay, enzyme-linked immunosorbent assay, Western blotting analysis.Results : The cell viability of SSO(0∼500 μl/mL) processing group was 96.9% and the processing of SSO didn't have an effect on the cytotoxicity. The inhibitory effect of the nitric oxide (no) production of SSO(500 μg/mL, 50 μg/mL, 10 μg/mL) was each 70.3%, 37.6% and 26.5%. IL-1β production inhibition ability of SSO(500 μg/mL, 100 μg/mL) was each 49.88% and 48.8%. PGE2 production inhibition ability of SSO(500 μg/mL, 100 μg/mL) was each 49.88% and 73.1%, 70.5%. By using SSO, it experimented about iNOS protein expression inhibition ability, that is the NO production enzyme. iNOS protein expression increased in the group processing LPS independently. iNOS protein expression decreased in the group processing SSO together. The expression of the COX-2 protein decreased 89.6%, 81.8% in the group processing SSO. The significance was in the relationship with NO formation inhibition with the relationship with the PGE2 formation inhibition and iNOS protein, it confirmed in SSO with the COX-2 protein.Conclusions : Stimulation of the RAW 264.7 cells with LPS caused an elevated production of nitric oxide (NO), IL-1β and PGE2 which was markedly inhibited by the pretreatment with SSO without causing any cytotoxic effects. The reduced expressions of iNOS protein were consistent with the reductions in NO production in the culture media. SSO may be useful for the treatment of various inflammatory diseases.

Two acyl phenol glucosides as Inhibitors of iNOS from Popolus davidiana in LPS- activated macrophages

  • Kim, Ji-Sun;Lee, Hwa-Jin;Kim, Yong-Kyun;Ryu, Jae-Ha
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.203.2-204
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    • 2003
  • Nitric oxide (NO) produced in large amounts by inducible nitric oxide synthase (iNOS) is known to be responsible for the vasodilation and hypotension observed in septic shock and inflammation. 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 woody plants and screened the inhibitory activity of NO production in lipopolysaccharide (LPS)-activated macrophages after the treatment of these extracts. (omitted)

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Cedrela sinensis Leaves Suppress Oxidative Stress and Expressions of iNOS and COX-2 via MAPK Signaling Pathways in RAW 264.7 Cells

  • Bak, Min-Ji;Jeong, Jae-Han;Kang, Hye-Sook;Jin, Kyong-Suk;Ok, Seon;Jeong, Woo-Sik
    • Preventive Nutrition and Food Science
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    • v.14 no.4
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    • pp.269-276
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    • 2009
  • Overproduction of reactive oxygen species (ROS), including nitric oxide (NO), could be associated with the pathogenesis of various diseases such as cancer and chronic inflammation. Inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) are known to play key roles in the development of these diseases. Cedrela sinensis leaves have been used in Asian countries as a traditional remedy for enteritis, dysentery and itching. In the present study, we investigated the anti-inflammatory effects of Cedrela sinensis leaves in lipopolysaccharide (LPS)- stimulated RAW 264.7 macrophages. Powder of C. sinensis leaves was extracted with 95% ethanol and fractionated with a series of organic solvents including n-hexane, dichloromethane, ethyl acetate, n-butanol, and water. The dichloromethane (DCM) fraction strongly inhibited NO production possibly by down-regulating iNOS and COX-2 expression, as determined by Western blotting. Hydrogen peroxide-induced generation of reactive oxygen species (ROS) was also effectively inhibited by the DCM fraction from C. sinensis leaves. In addition, C. sinensis inhibited LPS-mediated p65 activation via the prevention of IκB-$\alpha$ phosphorylation. Furthermore, mitogen-activated protein kinases (MAPKs) such as ERK 1/2 and p38 were found to affect the expression of iNOS and COX-2 in the cells. Taken together, our data suggest that leaves of C. sinensis could be used as a potential source for anti-inflammatory agents.

m2 Muscarinic Receptors Stimulate Neuronal Nitric Oxide Synthase

  • Lee, Seok-Yong;Park, Sun-Hye;Cho, Tai-Soon
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1996.04a
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    • pp.208-208
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    • 1996
  • In this work we investigated coupling of the m2 and m4 subtypes of muscarinic acetylcholine receptors expressed in chinese hamster ovary (CHO) cells to activation of neuronal nitric oxide synthase (nNOS). Stimulation of guanylate cyclase activity in detector neuroblastoma cells was used as an index of generation of nitric oxide (NO) in CHO cells. The agonist carbachol induced marked time and concentration-dependent enhancement of the activity of nNOS at m2 receptors. In sharp contrast, the response in CHO cells transfected with the m4 receptor gene was similar in magnitude to that observed in non-transfected cells, suggesting lack of significant coupling of m4 muscarinic receptors to NO signaling. This novel observation of functional divergence of the two muscarinic receptor subtypes at the level of activation of nNOS is quite intriguing, in light of the currently accepted dogma that they belong to the same functional class. This functional selectivity was not due to differential effects on intracellular Ca$\^$2+/ concentration, since activation of both subtypes of muscarinic receptors produced a comparable, albeit quite small, Ca$\^$2+/ signal. Taken together, our present data strongly suggest that the generally assumed functional equivalence of m2 and m4 muscarinic receptors should be carefully reexamined. These data also suggest the presence of alternate mechanisms of activation of nNOS, which might be operative in the absence of large changes in the concentration of cellular Ca$\^$2+/. The latter mechanisms are expected to be activated by m2, but not m4 muscarinic receptors. Both sets of findings are quits important in regards to refining the functional classification of muscarinic receptor subtypes and the cellular mechanisms of activation of NOS.

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Ethanolic Extract of Chondria crassicaulis Inhibits the Expression of Inducible Nitric Oxide Synthase and Cyclooxygenase-2 in LPS-Stimulated RAW 264.7 Macrophages

  • Kim, Yeon-Kye;Jeong, Eun-Ji;Lee, Min-Sup;Yoon, Na-Young;Yoon, Ho-Dong;Kim, Jae-Il;Kim, Hyeung-Rak
    • Fisheries and Aquatic Sciences
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    • v.14 no.4
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    • pp.275-282
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    • 2011
  • Inflammatory mediators such as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) have been implicated in various inflammatory diseases. In this study, we investigated the anti-inflammatory activities of Chondria crassicaulis ethanolic extract (CCE) by measuring its effects on the expression of iNOS and COX-2 proteins in lipopolysaccharide (LPS)-treated RAW 264.7 murine macrophages. CCE significantly and dose-dependently inhibited the LPS-induced release of nitric oxide and prostaglandin $E_2$, and suppressed the expression of iNOS and COX-2 proteins in LPS-stimulated RAW 264.7 cells, without causing any cytotoxicity. It also inhibited the production of the pro-inflammatory cytokines such as interleukin (IL)-$1{\beta}$, IL-6, and tumor necrosis factor (TNF)-${\alpha}$ in LPS-stimulated RAW 264.7 cells. Moreover, treatment with CCE strongly suppressed nuclear factor-${\kappa}B$ (NF-${\kappa}B$) promoter-driven expression in LPS-treated RAW 264.7 cells. CCE treatment blocked nuclear translocation of the p65 subunit of NF-${\kappa}B$ by preventing proteolytic degradation of inhibitor of ${\kappa}B-{\alpha}$. These results indicate that CCE regulates iNOS and COX-2 expression through NF-${\kappa}B$-dependent transcriptional control, and identifies potential candidates for the treatment or prevention of inflammatory diseases.