• Title/Summary/Keyword: nitric oxide

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The Inhibitory Activity of Erigeron annuus-Derived Components on $Interferon-{\gamma}$ and Lipopolysaccharide-Induced Nitric Oxide Production in Mouse Pheritoneal Macrophage

  • Lee, Hee-Jung;Kim, You-Ah;Jeong, Na-Ho;Hong, Seung-Heon;Seo, Young-Wan
    • Journal of Applied Biological Chemistry
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    • v.50 no.3
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    • pp.160-163
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    • 2007
  • Two flavonoids (1 and 2) and one phenolic acid (3) obtained from Erigeron annuus have recently been shown to have potent antioxidant activities. Aim of this study was to investigate the inhibitory effects of these components on $interferon-{\gamma}$ and lipopolysaccharide-induced nitric oxide productions in the mouse pheritoneal macrophage. Compounds 2 and 3 showed marked inhibitory activities against inducible nitric oxide synthase (iNOS) on the lipopolysaccharide and $interferon-{\gamma}-stimulated$ mouse pheritoneal macrophages without cytotoxicity. Therefore, these results suggest that the compounds could be effective anti-inflammatory agents as nitric oxide inhibitors in vivo.

Inhibitory Effect of Esculetin on the Inducuble Nitric Oxide Synthase Expression in TNF-stimulated 3T3-L1 Adipocytes

  • Yang, Jeong-Yeh
    • The Korean Journal of Physiology and Pharmacology
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    • v.7 no.5
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    • pp.283-287
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    • 2003
  • While nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) is beneficial for host survival, it is also detrimental to the host. Thus, regulation of iNOS gene expression may be an effective therapeutic strategy for the prevention of unwanted reactions at various pathologic conditions. During the screening process for the possible iNOS regulators, we observed that esculetin is a potent inhibitor of cytokine-induced iNOS expression. The treatment of 3T3-L1 adipocytes with the tumor necrosis factor-${\alpha}$ (TNF) induced iNOS expression, leading to enhanced NO production. TNF-induced NO production was inhibited by esculetin in a dose-dependent manner. Esculetin inhibited the TNF-induced NO production at the transcriptional level through suppression of iNOS mRNA and subsequent iNOS protein expression. These results suggest esculetin, a component of natural products, as a naturally occurring, nontoxic means to attenuate iNOS expression and NO-mediated cytotoxicity.

Yomogin, an Inhibitor of Nitric Oxide Production in LPS-Activated Macrophages

  • Ryu, Jae-Ha;Lee, Hwa-Jin;Jeong, Yeon-Su;Ryu, Shi-Yong;Han, Yong-Nam
    • Archives of Pharmacal Research
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    • v.21 no.4
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    • pp.481-484
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    • 1998
  • In activated macrophages the inducible form of nitric oxide synthase (i-NOS) generates high amounts of toxic mediator, nitric oxide (NO) which contributes to the circulatory failure associated with septic shock. A sesquiterpene lactone compound (yomogin) isolated from medicinal plant Artemisia princeps Pampan inhibited the production of NO in LPS-activated RAW 264.7 cells by suppressing i-NOS enzyme expression. Thus, yomogin may be a useful candidate for the development of new drugs to treat endotoxemia and inflammation accompanied by the overproduction of NO.

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Effects of Nitric Oxide on the Neuronal Activity of Rat Cerebellar Purkinje Neurons

  • Jang, Su-Joong;Jeong, Han-Soong;Park, Jong-Seong
    • Biomedical Science Letters
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    • v.16 no.4
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    • pp.259-264
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    • 2010
  • This study was designed to investigate the effects of nitric oxide on the neuronal activity of rat cerebellar Purkinje cells. Sprague-Dawley rats aged 14 to 16 days were decapitated under ether anesthesia. After treatment with pronase and thermolysin, the dissociated Purkinje cells were transferred into a chamber on an inverted microscope. Spontaneous action potentials and potassium current were recorded by standard patch-clamp techniques under current and voltage-clamp modes respectively. 15 Purkinje cells revealed excitatory responses to $20\;{\mu}M$ of sodium nitroprusside (SNP) and 4 neurons (20%) did not respond to SNP. Whole potassium currents of Purkinje cells were decreased by SNP (n=10). Whole potassium currents of Purkinje cells were also decreased by L-arginine, substrate of nitric oxide (n=10). These experimental results suggest that nitric oxide increases the neuronal activity of Purkinje cells by altering the resting membrane potential and after hyperpolarization.

Verticillium dahliae toxins-induced nitric oxide production in Arabidopsis is major dependent on nitrate reductase

  • Shi, Fu-Mei;Li, Ying-Zhang
    • BMB Reports
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    • v.41 no.1
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    • pp.79-85
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    • 2008
  • The source of nitric oxide (NO) in plants is unclear and it has been reported NO can be produced by nitric oxide synthase (NOS) like enzymes and by nitrate reductase (NR). Here we used wild-type, Atnos1 mutant and nia1, nia2 NR-deficient mutant plants of Arabidopsis thaliana to investigate the potential source of NO production in response to Verticillium dahliae toxins (VD-toxins). The results revealed that NO production is much higher in wild-type and Atnos1 mutant than in nia1, nia2 NR-deficient mutants. The NR inhibitor had a significant effect on VD-toxins-induced NO production; whereas NOS inhibitor had a slight effect. NR activity was significantly implicated in NO production. The results indicated that as NO was induced in response to VD-toxins in Arabidopsis, the major source was the NR pathway. The production of NOS-system appeared to be secondary.

Inhibitors of Nitric Oxide Synthesis from Ginseng in Activated Macrophages (활성화한 RAW 264.7 세 포주에서 인삼 Polyacetylene류의 Nitric Oxide 생성저해)

  • 류재하;장세란
    • Journal of Ginseng Research
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    • v.22 no.3
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    • pp.181-187
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    • 1998
  • Nitric Oxide (NO), derived from L-arginine, is produced by two types (constitutive and inducible) of nitric oxide synthase (NOS). The NO produced in large amounts by the inducible NOS is known to be responsible for the vasodilation and hypotension observed in septic shock. We have found three polyacetylene compounds which inhibited the production of NO in LPS-activated RAW 264.7 cells. Their structures were identified as panauynol, ginsenoyne A and PQ-6 by the spec- troscopic analysis (IC50 values were 32.3 $\mu$M, 2.3 $\mu$M, 1.5 $\mu$M, respectively). These polyacetylenes may be useful candidates for the development of new drug to treat endotoxemia and inflammation accompanied by the overproduction of NO.

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Harpagophytum Procumbens Suppresses Lipopolysaccharide Induced Expressions of Cyclooxygenase-2 and Inducible Nitric Oxide Synthase in Mouse BV2 Microglial Cells

  • Cho, Hyun-Chol;Song, Yun-Kyung;Lim, Hyung-Ho
    • The Journal of Korean Medicine
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    • v.26 no.4
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    • pp.152-161
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    • 2005
  • The excessive release of proinflammatory products by activated microglia causes neurotoxicity, and this has been implicated in the pathogenesis of neurodegenerative diseases. Harpagophytum procumbens (Pedaliaceae) has been widely used for the treatment of pain and arthritis in the clinical field. In this study, we investigated the effect of Harpagophytum procumbens against lipopolysaccharide-induced inflammation. From the present results, the aqueous extract of Harpagophytum procumbens was shown to suppress prostaglandin-E2 synthesis and nitric oxide production by inhibiting the lipopolysaccharide-stimulated enhancement of cyclooxygenase-2 and inducible nitric oxide synthase expressions in mouse BV2 microglial cells. These results suggest that Harpagophytum procumbens may offer a valuable means of therapy for the treatment of brain inflammatory diseases by attenuating lipopolysaccharide-induced prostaglandin-E2 synthesis and nitric oxide production.

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Effect of Chronic Inhibition of Nitric Oxide on Blood Pressure and Apoptosis in the Blood Pressure-Associated with Organs

  • Bae, Hyung-Joon
    • Biomedical Science Letters
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    • v.16 no.1
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    • pp.25-32
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    • 2010
  • Sprague-Dawley(SD) rats were orally administered with $N^G$-nitro-L-arginine methyl ester(L-NAME) which inhibits or blocks the production of nitric oxide from L-arginine in vascular endothelial cells and vessel tissue to statistically examine the effects of nitric oxide on some physiological changes such as blood pressure and heart rate, and to confirm the apoptosis induced by the suppressed nitric oxide activity in some related organs under light microscope. Systolic blood pressure significantly increased 28.5% by the chronic treatment of L-NAME for 8 weeks (P<0.001), no significant difference, however, was observed in heart rate between the control group and the L-NAME-treated group regardless of their age. Hematoxylin-eosin staining showed some histological alterations only in kidney among the examined organs; heart, liver, pancreas, and adrenal gland from the L-NAME-treated group. TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling) test showed a strong positive reaction, representing that the chronic treatment of L-NAME facilitates apoptosis, in the cortex and medulla of kidney, but not any significance detectable in the other organs. These results conclude that chronic treatment of L-NAME significantly increases blood pressure, and that the followed inhibition of nitric oxide synthesis occurs a typical inducement of apoptosis in kidney.

Effect of Thesium Chinense Turczaninow on Breast Cancer Chemopreventive enzyme activity in In vitro (In vitro에서의 댑싸리하고초의 유방암예방효소 활성에 미치는 영향)

  • Shon, Yun-Hee;Kim, Mee-Kyung;Park, Sun-Dong;Nam, Kyung-Soo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.20 no.3
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    • pp.675-679
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    • 2006
  • The effect of water extract from Thesium chinese Turczaninow (TCTW) on proliferation of human breast cancer cells, nitric oxide production, nitric oxide synthase expression, and ornithine decarboxylase activity was tested. TCTW inhibited the growth of both estrogen-independent MDA-MB-231 and estrogen-dependent MCF-7 human breast cancer cells. Lipopolysaccharide-induced nitric oxide (NO) production was significantly reduced by TCTW at the concentrations of 1.0 (p<0.05) and 5.0 mg/ml (p<0.005). Expression of inducible nitric oxide synthase (iNOS) was also suppressed with the treatment of TCTW in Western blot analysis. TCTW inhibited induction of ornithine decarboxylase by 12-O-tetradecanoylphorbol-13-acetate (TPA), a key enzyme of polyamine biosynthesis, which is enhanced in tumor promotion. Therefore, TCTW is worth further investigation with respect to breast cancer chernoprevention or therapy.

Effect of nitric oxide on the cyplal gene expression

  • Kim, Ji E.;Jung Y. Bae;Yhun Y. Sheen
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1998.11a
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    • pp.141-141
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    • 1998
  • In order to study the effect of nitric oxide on the regulation of mouse cyplal expression, 5' flanking DNA of mouse cytochrome P450 lal was cloned into pGL3 basic vector encoding luciferase gene. pcyplal-Luc was transfected into Hepa I cells and various chemicals were treated. Luciferase activity was stimulated 1000 folds over that of control by TCDD (2,3,7,8-tetrachloro-p-dioxin) treatment and this stimulation was dose dependent. When SNP (sodium nitroprusside) which donates nitric oxide was administrated, this stimulatory effect of TCDD on luciferase activity was decreased. And LPS (lipopolysaccharide) which is an iNOS (inducible nitric oxide synthase) inducer also decreased the stimulatory effect of TCDD on luciferase. And iNOS inhibitor N$\^$G/-nitro-ι-arginine + TCDD treatment increased the stimulation effect of TCDD and this effect was abolished when ι-arginine was added to N$\^$G/-nitro-ι-arginine + TCDD treatment. When N$\^$G/-nitro-ι-arginine was concomitantly administrated with SNP or LPS to confirm the effect of nitric oxide, the inhibitory effect of SNP or LPS was abolished. These data strongly suggest that nitric oxide might be an inhibitory regulator on the cytochrome P450 lal gene expression in Hepa cells.

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