• Title/Summary/Keyword: Inhibition of nitric oxide

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Involvement of nitric oxide and prostanoid on the endothelium -dependent vasodilatation by acetylcholine in the isolated rabbit renal artery (토끼 적출 신동맥에 있어서 acetylcholine에 의한 내피세포 의존성 이완작용에 대한 nitric oxide와 prostanoid의 연관성)

  • Kim, Joo-heon;Shim, Cheol-soo;Jeon, Seok-cheol
    • Korean Journal of Veterinary Research
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    • v.41 no.3
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    • pp.299-304
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    • 2001
  • The effect of the nitric oxide synthase(NOS) inhibitor, $N^{G}$-nitro-L-arginine methyl ester (L-NAME), and the prostanoid synthesis inhibitor, indomethacin, on the vasodilatation produced in response to acetylcholine(Ach) on the isolated rabbit renal artery was examined. The vasodilatory reponses to Ach($10^{-8}-3{\times}10^{-5}M$) were completely absent in thevessel which the endothelium had previous been removed. L-NAME($10^{-4}M$) significantly reduced the vasodilatory reponse to the Ach($10^{-8}-3{\times}10^{-5}M$). When L-arginine ($10^{-3}M$) was also present in the organ bath along with L-NAME($10^{-4}M$), this inhibitory effect of L-NAME ($10^{-4}M$) on the vasodilatory response to Ach ($10^{-8}-3{\times}10^{-5}M$) was significantly attenuated, Indomethacin ($10^{-6}M$) did not significantly affect the vasodilatory responses to Ach ($10^{-8}-3{\times}10^{-5}M$). The inhibition by L-NAME ($10^{-4}M$) and indomethacin ($10^{-6}M$) on vasodilatory response to Ach was significantly greater than the inhibition due to L-NAME ($10^{-4}M$) alone. The present study has established that Ach induce relaxation via and endothelium-dependent mechanism, this relaxation to Ach involves both nitric oxide(NO) and prostanoid in the isolated rabbit renal artery.

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Heterotopic electroacupuncture modulates formalin-induced pain via descending inhibition in the rat (백서(白鼠)의 formalin 유발(誘發) 통증(痛症)에 대한 전침자극(電鍼刺戟)과 하행성 진통기전)

  • Koo, Sung-Tae;Sohn, In-Chul;Kim, Jae-Hyo
    • Korean Journal of Acupuncture
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    • v.23 no.3
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    • pp.55-71
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    • 2006
  • Objectives : The present study was investigated the effect and pathway of heterotopic electroacupuncture (EA) on pain induced by formalin in rats. Methods : Acupoints in the right forepaws, $HT_7$ and $PC_7$, were stimulated with 3 mA, 2 ms, and 10 Hz before subcutaneously formalin injection (5%, $50{\mu}l$) to the left hind paw. Moreover, it was investigated whether the dorsolateral funiculus (DLF), as known to the descending inhibition, mediates analgesia of the heterotopic EA, and an administration of naltrexone blocks the effect of EA. Results : In the immunohistochemistry of cFos-like protein (cFL), there were inhibitory effects of EA on the increased expression of cFL in the lumbar spinal dorsal horn neurons following formalin injection. Especially, EA inhibited the expression of cFL on the superficial laminae than that on the deep laminae at 1 hr after, but that on the deep laminae than that on the superficial laminae at 2 hr after. Also, EA suppressed the increased expression of nitric oxide (NO) and neuronal nitric oxide synthase (nNOS) in the lumbosacral spinal cord after formalin injection, but not Sham-EA. Suppressed expressions of cFL, NO and nNOS in the spinal cord were eliminated after transection of the ipsilateral DLF at $T_{10}{\sim}T_{11}$ levels. However, pretreatment of naltrexone could not prevent the suppressive expressions of cFL, NO and nNOS at the spinal cord. Conclusions : These results suggest that the analgesia of heterotopic EA may be modulated through the DLF constituting the descending inhibition.

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Inducible Nitric Oxide Synthase Mediates the Triglyceride-induced Death of THP-1 Monocytes

  • Byung Chul Jung;Hyun-Kyung Kim;Jaewon Lim;Sung Hoon Kim;Yoon Suk Kim
    • Biomedical Science Letters
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    • v.29 no.2
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    • pp.66-74
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    • 2023
  • Triglyceride (TG) accumulation can cause monocytic death and suppress innate immunity. However, the signaling pathways involved in this phenomenon are not fully understood. This study aimed to examine whether inducible nitric oxide synthase (iNOS) is involved in the TG-induced death of THP-1 monocytes. Results showed that iNOS was upregulated in TG-treated THP-1 monocytes, and iNOS inhibition blocked TG-induced monocytic death. In addition, TG-induced poly (ADP-ribose) polymerase (PARP) cleavage and caspase-3 and -7 activation were suppressed by iNOS inhibition. Furthermore, the expression of X-linked inhibitor of apoptosis protein (XIAP) and survivin, which inhibit caspase-3 and -7, was reduced in TG-treated THP-1 monocytes, but iNOS inhibition recovered the TG-induced downregulation of XIAP and survivin expression. Considering that TG-induced monocytic death is triggered by caspase2 and -8, we investigated whether caspase-2 and -8 are linked to the TG-induced expression of iNOS in THP-1 monocytes. When the activities of caspase-2 and -8 were inhibited by specific inhibitors, the TG-induced upregulation of iNOS and downregulation of XIAP and survivin were restored in THP-1 monocytes. These results suggest that TG-induced monocytic death is mediated by the caspase-2/caspase-8/iNOS/XIAP and survivin/executioner caspase/PARP pathways.

Antioxidant and Anti-inflammatory Effects of Fractions from Pruni persicae Flos (도화(桃花, Pruni persicae Flos) 분획물의 항산화 및 항염증 효과)

  • Lee, Jin-Young;An, Bong-Jeun
    • The Korea Journal of Herbology
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    • v.27 no.5
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    • pp.55-63
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    • 2012
  • Objectives : The solvent extracts of Pruni persicae Flos were investigated for the activities of anti-oxidant and anti-inflammatory effects to apply as a functional ingredient for cosmetic products. Methods : In this study, the fractions of P. persicae Flos were extracted with 70.0% acetone and purified using Sephadex LH-20 column chromatography. As a result, eight fractions were isolated. We performed MTT assay, total polyphenol contents, DPPH free radical scavenging assay, SOD-like activity, xanthine oxidase inhibition assay, astringent activity assay, hyaluronidase inhibition assay and the production of nitric oxide. Results : For anti-oxidant effects, the electron donating ability of fraction (Fr.) 2-5, Fr.-8 isolated from P. persicae Flos was above 90.0% at 100 ppm respectively. The superoxide dismutase (SOD) - like activity of Fr.-5 isolated from P. persicae Flos was 92.1% at 1,000 ppm. The xanthine oxidase inhibitory effect of Fr.-6 isolated from P. persicae Flos was about 83.3% at 1,000 ppm. Hyaluronidase inhibition activity related to the anti-inflammation effect was 94.0% for Fr.-4 isolated from P. persicae Flos at 500 ppm. In the anti-inflammation effect, the Fr.-4 isolated from P. persicae Flos inhibited the generation of nitric oxide. Conclusions : All these findings suggested that the fractions of P. persicae Flos has a great potential as a cosmeceutical ingredient with a anti-oxidant and anti-inflammatory effects.

Antioxidant and Anti-Inflammatory Effects of NCW Peptide from Clam Worm (Marphysa sanguinea)

  • Park, Young Ran;Park, Chan-Il;Soh, Yunjo
    • Journal of Microbiology and Biotechnology
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    • v.30 no.9
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    • pp.1387-1394
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    • 2020
  • Clam worms (Marphysa sanguinea) are a rich source of bioactive components such as the antibacterial peptide, perinerin. In the present study, we explored the physiological activities of a novel NCWPFQGVPLGFQAPP peptide (NCW peptide), which was purified from clam worm extract through high-performance liquid chromatography. Tandem mass spectrometry (MS/MS) revealed that NCW was a new peptide with a molecular weight of 1757.86 kDa. Moreover, NCW peptide exhibited significant antioxidant effects, causing a 50% inhibition of DPPH radical at a concentration of 20 μM without showing any cytotoxicity. These were associated with a reduction in the activity of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) in LPS-stimulated RAW264. 7 cells. Furthermore, NCW peptide exhibited anti-inflammatory effects in LPS-stimulated RAW264.7 macrophages via inhibition of the abnormal production of pro-inflammatory cytokines including nitric oxide (NO), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2). These anti-inflammatory effects of NCW peptide were associated with the inhibition of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α). Our results therefore suggest that this novel NCW peptide with antioxidant and anti-inflammatory effects could be a good therapeutic agent against inflammation-related diseases.

p66shc Adaptor Protein Suppresses the Activation of Endothelial Nitric Oxide Synthase in Mouse Embryonic Fibroblasts

  • Lee, Sang-Ki;Kim, Young-Shin;Kim, Cuk-Seong;Son, Sook-Jin;Yoo, Dae-Goon;Lee, Kwon-Ho;Lee, Sang-Do;Park, Jin-Bong;Jeon, Byeong-Hwa
    • The Korean Journal of Physiology and Pharmacology
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    • v.10 no.3
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    • pp.155-159
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    • 2006
  • Among the Shc proteins, p66shc is known to be related to oxidative stress responses and regulation of the production of reactive oxygen species (ROS). The present study was undertaken to investigate the role of p66shc on endothelial nitric oxide synthase (eNOS) activity in the mouse embryonic fibroblasts (MEFs). When wild type (WT) or p66shc (-/-) MEFs were transfected with full length of eNOS cDNA, the expression and activity of eNOS protein were higher in the p66shc (-/-) MEFs. These phenomena were reversed by reconstitution of p66shc cDNA transfection in the p66shc (-/-) MEFs. The basal superoxide production in the p66shc (-/-) MEFs was not significantly different from that of WT of MEFs. However, superoxide production induced by NADPH in the p66shc (-/-) MEF was lesser than that in WT MEFs. When compared with WT MEFs, cell lysate of p66shc (-/-) MEFs showed significantly increased H-ras activity without change of endogenous H-ras expression. Our findings suggest the pivotal role of p66shc adaptor protein played in inhibition of endothelial nitric oxide production via modulation of the expression and/or activity of eNOS protein.

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
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    • 1996.04a
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    • pp.207-207
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    • 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.

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Inhibitory Activity of Nitric Oxide Synthase and Peroxynitrite Scavenging Activity of Extracts of Perilla frutescens (들깨 잎 추출물의 Nitric Oxide Synthase 저해활성 및 Peroxynitrite 소거활성)

  • Kim, Jae-Yeon;Kim, Ji-Sun;Jung, Chan-Sik;Jin, Chang-Bae;Ryu, Jae-Ha
    • Korean Journal of Pharmacognosy
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    • v.38 no.2 s.149
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    • pp.170-175
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    • 2007
  • Activated microglia by neuronal injury or inflammatory stimulation overproduce nitric oxide (NO) by inducible nitric oxide synthase (iNOS) and reactive oxygen species (ROS) such as superoxide anion, resulting in neurodegenerative diseases. The toxic peroxynitrite (ONOO$^-$), the reaction product of NO and superoxide anion further contributes to oxidative neurotoxicity. We tried to evaluate the effects of two kinds of varieties of Perilla frutescens var japnica Hara on the NO production in lipopolysaccharide (LPS)-activated microglia. The perilla cultivars of Namcheondeulkkae (NC) and Boradeulkkae (BR) were developed by pure line from the local variety and by a cross between 'deulkkae' and 'chajogi', respectively. Spirit, hexane, chloroform and butanol fractions of the leaves of NC and BR inhibited the production of NO in LPS-activated microglia. The fractions of BR showed stronger activity than NC and the spirit extracts was the most potent in both cultivars. The solvent fractions of BR suppressed the expression of protein and mRNA of iNOS in LPS-activated microglial cells. Moreover, the extracts of NC and BR showed the activity of peroxynitrite scavenging in cell free bioassay system. These results imply that Namcheondeulkkae and Boradeulkkae might have neuroprotective activity through the inhibition of NO production by activated microglial cells and peroxynitrite scavenging activity.

Nitro oxide in human cytomegalovirus replication and gene expression

  • Lee, Jee-Yeon;Lee, Chan-Hee
    • Journal of Microbiology
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    • v.35 no.2
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    • pp.152-157
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    • 1997
  • Infection of human fibroblast (HF) cells with human cytomegalovirus (HCMV) result in changes in the intracellular level of second messengers. Since nitric oxide (NO) production has been known to be related with other second messengers, it is probable that HCMV infection of HF cells may involve NO. To test this possibility, the amount of NO was measured following ogenous addition of NO generators such as sodium nitroprusside (SNP) or S-nitroso-N-a-cetylpenicillamine (SNAP) immediately after HCMV infection, however, inhibited virus multiplication. Furthermore, immunoblot experiment using monoclonal antibody to HCMV major immediate early (MIE) proteins or CAT assay using pCMVIE/CAT (plasmid containing CAT gene driven by HCMV MIE promoter) revealed that SNP or SNAP blocked the MIE gene expression. SNP was more effective than SNAP in hibiting HCMV multiplication or MIE gene expression. SNP produced more NO than SNAP in inhibiting HCMV multiplication or MIE gene expression. SNP produced more NO than SNAP. Although the mechanism for the inhibition of HCMV multiplication and MIE gene expression by NO is still elusive some correlation with NO-mediated inhibition of HCMV-induced increase in cytosolic free Ca$\^$2+/ concentration ([Ca$\^$2+/]) was observed. The increase of [Ca$\^$2+/] following HCMV infection was inhibited by SNP, and less effectively by SNAP. Raising [Ca$\^$2+/ with bromo-A23187 partially reversed the SNP block of MIE gene expression. Thus, there appear to e some relationships among NO. [Ca$\^$2+/], and HCMV MIE gene expression.

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Studies on the Regulation of Nitric oxide Synthesis in Murine Mononuclear Phagocytes (마우스 단핵 탐식 세포에서 Nitric oxide 생성의 조절 기전에 관한 연구)

  • 최병기;김수응
    • Environmental Analysis Health and Toxicology
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    • v.15 no.3
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    • pp.69-80
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    • 2000
  • ADP-rubosylation may be involved in the process of macrophage activation. Nitric oxide (NO) has emerged as an important intracellular and interacellular regulatory molecule with function as diverse as vasodilation, neural communication or host defense. NO is derived from the oxidation of the terminal guanidino nitrogen atom of L-arginine by the NADPH -dependent enzyme, nitric oxide synthase (NOS) which is one of the three different isomers in mammalian tissues. Since NO can exert protective or regulatory functions in the cell at a low concentration while toxic effects at higher concentrations, its role may be tightly regulated in the cell. Therefore, this paper was focused on signal transduction pathway of NO synthesis, role of endogenous TGF-$\beta$ in NO production. effect of NO on superoxide formation. Costimulation of murine peritoneal macrophages with interferon-gamma (IFN-γ) and phorbol 12-myristate 13-acetate (PMA) increased both NO secretion and mRNA expression of inducible nitric oxide synthase (iNOS) when PMA abolished costimulation. Pretreatmnet of the cells with PMA abolished costimuation effects due to the depletion of protein kinase C (PKC) activities . The involvement of PKC in NO secretion could be further confirmed by PKC inhibitor, stauroprine, and phorbol ester derivative, phorbol 12,13-didecanoate. Addition of actinomycine D in IFN-γ plus PMA stimulated cells inhibited both NO secretion and mRNA expression of iNOS indication that PMA stabilizes mRNA of iNOS . Exogenous TGF-$\beta$ reduced NO secretion in IFN -γ stimulated murine macrophages. However addition of antisense oligodeoxynucleotide (ODN) to TGF-$\beta$ to this system recovered the ability of NO production and inhibited mRNA expression of TGF-$\beta$. ACAS interactive laser cytometry analysis showed that transportation of FITC -labeled antisense ODN complementary to TGF-$\beta$ mRNA could be observed within 5 min and reached maximal intensity in 30 min in the murine macrophage cells. NO released by activated macrophages inhibits superoxide formation in the same cells . This inhibition nay be related on NO-induced auto -adenosine diphosphate (ADP) -ribosylation . In addition, ADP-ribosylation may be involved in the process of macrophage activation .

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