• The Korean Journal of Pain
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• v.19 no.2
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• pp.142-145
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• 2006

Background: Nitric oxide (NO) is involved in the transmission and modulation of nociceptive information at the peripheral, spinal cord and supraspinal levels. We conducted this experiment to assess the antinociceptive effects of a nonselective nitric oxide synthase (NOS) inhibitor, N-nitro-L-arginine methyl ester (L-NAME), on the modulation of pain in rats subjected to the formalin test. Methods: Formalin 5% was injected in the right hind paw after intraperitoneal (IP) injection of various doses of L-NAME (0.5 mg/kg, 1.5 mg/kg with and without L-arginine 100 mg/kg, 5.0 mg/kg). The number of flinches was measured. Results: Formalin injected into the rat hind paw induced a biphasic nociceptive behavior. IP injected L-NAME diminished the nociceptive behaviors in a dose-dependent manner during phases 1 and 2. The concomitant injection of L-arginine reversed the antinocipetive effect of L-NAME. Conclusions: The data demonstrates that a nonselective NOS inhibitor, L-NAME, possesses antinociceptive properties in rats subjected to the formalin test, and the antinociceptive effect of L-NAME is reversed by the concomitant administration of L-arginine.

• Korean Journal of Pharmacognosy
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• v.35 no.4 s.139
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• pp.283-287
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• 2004

The effect of water extract from Cnidii Rhizoma (CRW) on proliferation of human breast cancer cells, nitric oxide production, nitric oxide synthase expression, and ornithine decarboxylase activity was tested. CRW inhibited the growth of both estrogen-dependent MCF-7 and estrogen-independent MDA-MB-23I human breast cancer cells. Lipopolysaccharide-induced nitric oxide (NO) production was significantly reduced by CRW at the concentration of 0.5, 1.0 and 5.0 mg/ml. Expression of inducible nitric oxide synthase (iNOS) was also suppressed with the treatment of CRW in Raw 264.7 cells. CRW inhibited induction of ornithine decarboxylase by 12-0-tetradecanoylphorbol-13-acetate, a key enzyme of polyamine biosynthesis, which is enhanced in tumour promotion. Therefore, CRW is worth further investigation with respect to breast cancer chemoprevention or therapy.

• The Journal of Internal Korean Medicine
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• v.35 no.3
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• pp.262-273
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• 2014

Objectives: This study was carried out to investigate the protective effect of Coptidis Rhizoma steamed with rice wine (CR) against gastroduodenal mucosal injury through inhibiting inducible nitric oxide synthase (iNOS) activation. Methods: In in vitro experiment, LPS-induced RAW 264.7 macrophages were treated with CR(0.4, 0.6, 0.8, 1.0 mg/ml) and iNOS mRNA expression and nitric oxide (NO) production were measured. In in vivo experiment normal group mice were treated with neither ethanol nor CR. Both control and sample group mice were orally administrated with ethanol. Five hours after ethanol administration control group mice were orally administrated with distilled water, sample group mice were orally administrated with CR. After three days administration, gastroduodenal mucosa of mice was observed histopathologically and iNOS, nuclear factor-kappa B (NF-${\kappa}B$) activation were observed immunohistochemically. Results: In in vitro experiment iNOS mRNA expression and NO production in LPS-induced RAW 264.7 macrophages were decreased by CR dose-dependently. In in vivo experiment, gastroduodenal mucosal injury was repaired by CR and iNOS, NF-${\kappa}B$ activation in gastroduodenal mucosa were decreased by CR. Conclusions: Coptidis Rhizoma steamed with rice wine has a protective effect against gastroduodenal mucosal injury through inhibiting iNOS activation.

• The Korea Journal of Herbology
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• v.21 no.4
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• pp.59-67
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• 2006

Objectives : Sam-Myo-Whan(SMW) has been known traditional prescription with anti- anthritis activities. We investigated inhibitory effects of SMW on lipopolysaccharide (LPS)-induced nitric oxide(NO), $TNF-{\alpha}$ and inducible nitric oxide synthase(iNOS) production from RAW264.7 cells and BV-2 Microglia cells. Methods : SMW, which had been extracted with 70% MeOH, concentrated and freeze-dried was used for this experiment. After BV2 mouse brain macrophages and RAW264.7 mouse peritoneal macrophages were pretreated with increasing concentrations of SMW extract for 30min, and then activated with LPS. To investigate cytotoxicity of SMW extract, cell viability was measured by MTT assay. NO production was measured in each culture supernatant by Griess reaction. mRNA expression of iNOS in two type cells was investigated by RT-PCR. $TNF-{\alpha}$ production was measured in each culture supernatant by ELISA. Results : SMW extract significantly inhibited LPS-induced NO and $TNF-{\alpha}$ production in BV2 cells and RAW264.7 cells dose-dependently. SMW extract also greatly suppressed mRNA expression of iNOS in both type cells activated with LPS. Conclusion : These data suggests that SMW extract may have an anti-inflammatory effect through the inhibition of iNOS expression.

• Journal of Photoscience
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• v.9 no.2
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• pp.205-208
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• 2002

Nitric oxide (NO) is a newly described transmitter involved with cell to cell communication that is generated in biologic tissues by specific types of nitric oxide synthase (NOS), which metabolize L-arginine and molecular oxygen to citrulline and nitric oxide. In the skin. NO has been reported to play an important role in such diseases as psoriasis, atopic dermatitis, and contact dermatitis, as well as act as an important modulator in UVB-induced erythema. Ultraviolet B irradiation to the skin evokes an increase in NO production in the epidermis through two pathways; induction of inducible NOS, mediated by inflammatory cytokines, and elevation of constitutive neuronal NOS activity. In a cell culture system, it has been demonstrated that NO functions as a melanogen after being produced in keratinocytes in response to UVB-irradiation. NO-stimulated melanogenesis in melanocytes is mediated by the cGMP/PKG pathway. In this study, up-regulation of tyrosinase gene expression by NO-stimulation and the involvement of NO in UVB-induced pigmentation were examined. In NO-induced melanogenesis, protein synthesis and tyrosinase activity increased along with an up-regulation of tyrosinase gene expression. In an animal model, UVB-induced pigmentation in skin was suppressed by sequential daily treatments with a specific inhibitor of NOS. Thus, NO plays an important role in UVB-induced pigmentation, where its function as a melanogen is considered to be one of the mechanisms. Together with its role in the development of erythema, NO contributes to the total protective response of skin against UVB-irradiation.

• 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)

• Journal of Life Science
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• v.15 no.3 s.70
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• pp.344-351
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• 2005

Nitric oxide (NO) and calcium-binding proteins occur in various types of cells in the central nervous system. They are important signaling and calcium buffering molecules, respectively. In the present study, using immunocytochemistry we examined the distribution and the co-localization pattern of neurons containing neuronal nitric oxide synthase (nNOS) and parvalbumin in the visual cortex of hamster. The overall number of parvalbumin-immunoreactive (IR) neurons was 17 times higher than that of the nNOS-IR neurons in the hamster visual cortex. The highest differences were found in layer V, where parvalbumin-IR neurons were 54.7 times more abundant than nNOS-IR neurons. Many nNOS- and parvalbumin-IR neurons were similar in size, shape, and manner of distribution in the visual cortex. However, two-color immunofluorescence revealed that no neurons in the hamster visual cortex expressed both nNOS and parvalbumin. The present results indicate that there are subtle species differences in the co-localization pattern between nNOS and calcium-binding proteins. The present results also suggest not only the heterogeneity and functional diversity of nNOS-IRneurons in the visual cortex, but also the importance of understanding animal diversity

• Biomolecules & Therapeutics
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• v.22 no.6
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• pp.510-518
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• 2014

Chronic (>24 h) exposure of arsenite, an environmental toxicant, has shown the decreased nitric oxide (NO) production in endothelial cells (EC) by decreasing endothelial NO synthase (eNOS) expression and/or its phosphorylation at serine 1179 ($eNOS-Ser^{1179}$ in bovine sequence), which is associated with increased risk of vascular diseases. Here, we investigated the acute (<24 h) effect of arsenite on NO production using bovine aortic EC (BAEC). Arsenite acutely increased the phosphorylation of $eNOS-Thr^{497}$, but not of $eNOS-Ser^{116}$ or $eNOS-Ser^{1179}$, which was accompanied by decreased NO production. The level of eNOS expression was unaltered under this condition. Treatment with arsenite also induced reactive oxygen species (ROS) production, and pretreatment with a ROS scavenger N-acetyl-L-cysteine (NAC) completely reversed the observed effect of arsenite on $eNOS-Thr^{497}$ phosphorylation. Although protein kinase C (PKC) and protein phosphatase 1 (PP1) were reported to be involved in $eNOS-Thr^{497}$ phosphorylation, treatment with PKC inhibitor, Ro318425, and overexpression of various PKC isoforms did not affect the arsenite-stimulated $eNOS-Thr^{497}$ phosphorylation. In contrast, treatment with PP1 inhibitor, calyculin A, mimicked the observed effect of arsenite on $eNOS-Thr^{497}$ phosphorylation. Lastly, we found decreased cellular PP1 activity in arsenite-treated cells, which was reversed by NAC. Overall, our study demonstrates firstly that arsenite acutely decreases NO production at least in part by increasing $eNOS-Thr^{497}$ phosphorylation via ROS-PP1 signaling pathway, which provide the molecular mechanism underlying arsenite-induced increase in vascular disease.

• 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.

• 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 .