• Journal of Photoscience
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• v.4 no.2
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• pp.31-34
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• 1997

The rapid and spontaneous interaction between superoxide anion radical and nitric oxide to yield the potent oxidants. peroxynitrite artion and peroxynitrous acid, was investigated in phorbol myristate acetate(PMA)-stimulated RAW264.7 macrophases by means of lucigenin- or luminol-enhanced chemiluminescence method. When RAW264.7 macrophages were stimulated by PMA. peroxynitrite-induced chemiluminescence was clearly observed. To prove observed chemiluminescencc due to the reaction between superoxide anion radical and nitric oxide produced by RAW264.7 macrophases, N-nitrosoglutathione (GSNO), a nitric oxide-releasing compound. superoxide dismutase(SOD), an enzyme removing superoxide anion radical by dismutating superoxide artion radical to hydrogen peroxide, and N-acethyl cysteine(NAC), a scarvenging reagent both superoxide artion radical and nitric oxide, were added in the cell system. Peroxynitrite- induced chemilumincscence was increased by exogenous addition of GSNO. whereas observed chemiluminescence was decreased by SOD and NAC. These results suggest that PMA-stimulated RAW264.7 macrophages produce both superoxide anion radical and nitric oxide to form peroxynitrite.

• Korean Journal of Veterinary Research
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• v.57 no.1
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• pp.17-21
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• 2017

The aim of this study was to compare serum nitrotyrosine concentrations in healthy dogs with those in dogs with myxomatous mitral valve disease (MMVD). Fifty client-owned dogs were included in this study. Based on echocardiographic results, dogs were categorized into healthy (control), mild-, moderate-, and severe-MMVD groups. Serum nitrotyrosine concentrations were determined from enzyme-linked immunosorbent assays. No significant difference between control dogs and dogs with mild MMVD was detected (p = 0.31). However, dogs with moderate MMVD had significantly higher serum concentrations of nitrotyrosine (p = 0.04) than that in controls, and dogs with severe MMVD had significantly lower serum concentrations of nitrotyrosine (p = 0.03) than that in moderate MMVD dogs. There were negative correlations in the association of serum nitrotyrosine with age (n = 30, $R^2=0.067$, p = 0.27), left atrial-to-aortic root diameter ratio (n = 30, $R^2=0.02$, p = 0.57), and platelet count (n = 30, $R^2=0.39$, p = 0.003); however, only the platelet correlation was significant. Among dogs with MMVD, there was no significant difference in serum nitrotyrosine concentration between males and females. The results of this study suggest that tyrosine nitration end-products might be potential biomarkers for the detection of MMVD in dogs.

• Journal of Ginseng Research
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• v.34 no.3
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• pp.205-211
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• 2010

Korean red ginseng (KRG) has been used worldwide as a traditional medicine for the treatment of various diseases, including cancer. In this study, we determined the effect of KRG on the responses of HaCaT cells to peroxynitrite ($ONOO^-$). Cells has been used worldwide as a traditional medicine for the treatment of various diseases, including cancer. In this study, we determined the effect of KRG on the responses of HaCaT cells to peroxynitrite ($ONOO^-$). Cells treated with $ONOO^-$ (2 mM) prior to incubation with control medium for 12 hours displayed reduced viability, as determined using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay (viability about 48% of that of non-treated control cells). When KRG was added to the post-incubation medium, the negative effects of $ONOO^-$ on cell viability were significantly reduced. Reverse transcription-polymerase chain reaction analysis indicated that KRG alone did not significantly alter p53 or "growth arrest and DNA damage" (GADD)45 mRNA levels. However, the addition of KRG to the post-incubation medium significantly and dose-dependently reduced levels of p53 and GADD45 mRNA in $ONOO^-$-treated cells. Western blot analyses revealed that incubation with KRG decreased p53 and GADD45 protein levels in $ONOO^-$-treated cells, relative to those in cells incubated with control medium. Collectively, these results suggest that Korean red ginseng extract protects cells against $ONOO^-$-induced genotoxicity by increasing cell viability through modulating the expression of p53 signaling intermediates.