• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.6
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• pp.1475-1481
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• 2008

This study was to investigate the inhibitory effects of Mori Fructus on the generation of peroxynitrite ($ONOO^-$), nitric oxide (NO) and superoxide anion radical (${\cdot}O_2{^-}$) in the endothelial cells of rat vessels. The aim of this study was to investigate the $ONOO^-$, NO, ${\cdot}O_2{^-}$ scavenging and anti-inflammatory activitives of Mori Fructus. For this study, the fluorescent probes, namely dihydrorhodamine 123 (DHR 123), 4,5-diaminofluorescein (DAF-2) and 2',7'-dichlorodihydrofluorescein diacetate (DCFDA) were used. Western blotting was performed using anti-NF-${\kappa}B$ (p50, p65), anti-COX-2, anti-iNOS antibodies, respectively. Mori Fructus prevented lipopolysaccharide (LPS)-induced cell death in YPEN cells. Mori Fructus inhibited the generation of $ONOO^-$, NO and ${\cdot}O_2{^-}$ in the LPS-treated cells. Mori Fructus inhibited the expression of COX-2 and iNOS genes by means of decreasing the NF-${\kappa}B$ activation. These results suggest Mori Fructus is effective on inhibiting the generation of $ONOO^-$, NO and ${\cdot}O_2{^-}$, and that therefore it might have a potential role as a treatment for the inflammatory process and inflammation-related diseases.

• International Journal of Vascular Biomedical Engineering
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• v.2 no.2
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• pp.1-9
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• 2004

The history of studies in biology regarding reactive oxygen species (ROS) is approximately 40 years. During the initial 30 years, it appeared that these studies were mainly focused on the toxicity of ROS. However, recent studies have identified another action regarding oxidative signaling, other than toxicity of ROS. Basically, it is suggested that ROS are reactive, and degenerate to biomolecules such as DNA and proteins, leading to deterioration of cellular functions as an oxidative stress. On the other hand, recent studies have shown that ROS act as oxidative signaling in cells, resulting in various gene expressions. Recently ROS emerged as critical signaling molecules in cardiovascular research. Several studies over the past decade have shown that physiological effects of vasoactive factors are mediated by these reactive species and, conversely, that altered redox mechanisms are implicated in the occurrence of metabolic and cardiovascular diseases ROS is a collective term often used by scientist to include not only the oxygen radicals($O2^{-{\cdot}},\;{^{\cdot}}OH$), but also some non-radical derivatives of oxygen. These include hydrogen peroxide, hypochlorous acid (HOCl) and ozone (O3). The superoxide anion ($O2^{-{\cdot}}$) is formed by the univalent reduction of triplet-state molecular oxygen ($^3O_2$). Superoxide dismutase (SOD)s convert superoxide enzymically into hydrogen peroxide. In biological tissues superoxide can also be converted nonenzymically into the nonradical species hydrogen peroxide and singlet oxygen ($^1O_2$). In the presence of reduced transition metals (e.g., ferrous or cuprous ions), hydrogen peroxide can be converted into the highly reactive hydroxyl radical (${^{\cdot}}OH$). Alternatively, hydrogen peroxide may be converted into water by the enzymes catalase or glutathione peroxidase. In the glutathione peroxidase reaction glutathione is oxidized to glutathione disulfide, which can be converted back to glutathione by glutathione reductase in an NADPH-consuming process.

• Natural Product Sciences
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• v.5 no.2
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• pp.80-84
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• 1999

Peroxynitrite is a cytotoxic intermediate produced by the reaction between the superoxide anion radical and nitric oxide. Flavonoids (afzelin, quercitrin and quercetin 3-O-sambubioside), and chlorogenic acid and its methyl ester obtained from leaves of loquat (Eriobotrya japonica) have recently been shown to scavenge 1,1-diphenyl-2-picrylhydrazyl radical and to inhibit lipid peroxidation in mouse liver homogenate. The aim of this study is to investigate the inhibitory effects of the above components on peroxynitrite produced stimulated by 3-morpholinosydnonimine (SIN-1) to produce superoxide anion radical and nitric oxide at the same time. In addition, the present study tests whether or not the components directly scavenge peroxynitrite itself. The results showed that the components with the aromatic ortho-dihydroxyl groups (catechol) were more potent inhibitors of peroxynitrite formation by SIN-1. In particular, the methyl ester form of chlorogenic acid showed the most potent inhibition. At $5\;{\mu}M$ concentration, the order of minimizing peroxynitrite formation were : methyl chlorogenic acid > quercitrin > quercetin 3-O-sambubioside > chlorogenic acid > afzelin. Authentic peroxynitrite was directly scavenged by the components in a manner similar to peroxynitrite formation by SIN-1. In particular, when compared with penicillamine as a positive control, methyl chlorogenate was as effective in inhibiting peroxynitrite formation and approximately 2 times more effective in scavenging an authentic peroxynitrite. These results demonstrate therefore, that components extracted from the leaves of Eriobotrya japonica effectively scavenged peroxynitrite.

• ALGAE
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• v.21 no.1
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• pp.149-156
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• 2006

The aim of the present study was to evaluate the antioxidant activity of red algae in Jeju Island. The algal extracts were obtained with MeOH and fresh water at 20 and 70°C, and screened for antioxidant activities using hydroxyl radical (HO·), superoxide anion (O2–), hydrogen peroxide (H2O2) and DPPH free radical scavenging assays. Among them, Gracilaria verrucosa methanolic extract at 20°C (20ME, 96.85%), G. textorii aqueous extract at 20°C (20AE, 88.01%), Grateloupia filicina 20AE (85.35%), and Polysiphonia japonica 20ME (94.92%) exhibited the highest scavenging activities against HO·, O2–, H2O2, and DPPH free radicals, respectively. Moreover, P. japonica (20ME and 70ME) is correlated between DPPH free radical scavenging activity and polyphenolic contents. These results indicate that some red algae in Jeju Island could be potential candidates for development of antioxidants.

• Journal of Acupuncture Research
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• v.20 no.4
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• pp.209-219
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• 2003

This study was performed to determine if Juglandis semen extract(JSE) has free radical scavenging and antioxidant activities. Superoxide anion generation by xanthine oxidase/xanthine and in neutrophils activated by phorbol-12, 13-dibutyrate was inhibited by JSE and its effect was dose-dependent. JSE also inhibited generation of $H_2O_2$ induced by glucose oxidase/glucose and in opossum kidney cells treated with antimycin A. JSE exerted a direct $H_2O_2$ scavenging effect. Exposure of opossum kidney cells to 1mM tBHP caused a significant increase in lipid peroxidation, which was prevented by JSE. JSE also prevented tBHP-induced LDH release. These data suggest that JSE has free radical scavenging and antioxidant activities. However, further studies should be carried out to find the active ingredient(s) of JSE that exerts radical scavenging action.

• Food Science and Biotechnology
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• v.18 no.1
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• pp.167-171
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• 2009

This study examined the antioxidative activity of delphinidin, a kind of anthocyanidin from eggplant. Cellular protective potential from oxidative damage by nitric oxide (NO), superoxide anion ($O_2^-$), and peroxynitrite ($ONOO^-$) using epithelial cell line LLC-PK1 cell as well as in vitro radical scavenging effects were investigated. Delphinidin showed strong in vitro radical scavenging effects against NO, $O_2^-$, and hydroxyl radical (${\cdot}OH$) in dose-dependent manners. In addition, delphinidin increased cell viability in LLC-PK1 cells in a concentration-dependent manner when viability was reduced by $ONOO^-$-induced oxidative damage. To elucidate the protective mechanisms of delphinidin from $ONOO^-$, sodium nitroprusside (SNP), and pyrogallol were also employed to generate NO and $O_2^-$, respectively. The treatment of delphinidin recovered reductions in cell viability caused by SNP and pyrogallol, indicating that delphinidin can attenuate oxidative stress induced by NO and $O_2^-$. The present study suggests that delphinidin is a promising anti oxidative agent.

• Korean Journal of Pharmacognosy
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• v.30 no.3
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• pp.255-260
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• 1999

In the previous report, E-kong-san, which is usually used for recovering health in traditional medicine, has been shown to decrease cisplatin induced nephrotoxicity in vivo and in vitro. The significant reduction of E-kong-san on the cisplatin induced nephrotoxicity led us to investigate whether the effect of this water extract was a result of triggering antioxidation. In monkey kidney Vero cells, E-kong-san at $5{\sim}10\;mg/ml$ was able to attenuate 2mM cisplatin-stimulated cell death by 46.8% and 31.8%, respectively. E-kong-san showed strong free radical scavengering activities on 1,1-diphenyl-2-picrylhydrazil (DPPH) radical and xanthine/xanthine oxidase (XOD) generated superoxide anion radical $(O_2^{-.})$. We further studied the effects of E-kong-san on lipid peroxidation in rat liver microsomes induced by enzymatic and nonenzymatic methods. Moreover, E-kong-san exhibited significant inhibition on both ascorbic $acid/Fe^{2+}$ and $ADP/NADPH/Fe^{3+}$ induced lipid peroxidation in rat liver microsomes. Based on these results, we suggest that E-kong-san protects the cisplatin induced cytotoxicity by its antioxidative mechanism.

• The Korean Journal of Food And Nutrition
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• v.10 no.1
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• pp.37-43
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• 1997

This study was undertaken to evaluate as antioxidant activity against lipid peroxidation. Silymarin and silybin extracted from Silybum marianum were successively purified wit solvent fractionation by silica gel column chromatography. These isoflavonoid inhibited superoxide anion production in the xanthine oxidase system. In the rat liver microsomes, silymarin or silybin rapidly inhibited lipid peroxidation which was initiated enzymatically by reduced nicotinamide adenine dinucleotide phosphate(NADPH) or non-enzymatically by ascorbic acid or Fenton's reagent (H2O2+Fe2+). Mitochondrial lipid peroxidation was also inhibited by silymarin and silybin. silymarin and silybin inhibited on terminating radical chain reaction during lipid peroxidation in the enzymatic system of microsomes or in the linoleic acid hydroperoxide induced peroxidation system.

• YAKHAK HOEJI
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• v.50 no.3
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• pp.191-198
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• 2006

Acanthopanax species have traditionally been used as a tonic, a sedative as well as in the treatment of rheumatism, hypertension and diabetes. In the present study, oxidative stress was induced in Vero cells by incubating the cells with glucose and the cell viability was measured by MTT assay. The concentration of glucose which 50% of cell viability was 125 mM $(IC_{50})$ and the cell viability was increased to $87.6{\pm}8.8%$ by treatment of the extracts of Acanthopanax divaricatus var. albeofructus. The antioxidative activity of water extract of different parts of the Acanthopanax plant was investigated by DPPH (1,1-diphenyl-2-picrylhydrazyl) assay, xylenol orange assay, TBARS (thiobarbituric acid reactive substances) assay and enzyme (superoxide anion and catalase) assay. Each extract (leaves, root, stem and fruits) of the plant showed free radical and $H_2O_2$ scavenging activity. The extract also inhibited lipid peroxidation and recovered enzyme (superoxide anion dismutase and catalase) activity in Vero cells treated with glucose.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.2
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• pp.205-213
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• 2019

The protective effect of Agrimonia pilosa var. (AP) extract on potassium dichromate ($K_2Cr_2O_7$)-induced cytotoxicity in cultured NIH3T3 fibroblasts, was examined by performing an XTT assay for the cell viability and antioxidative effects, such as lactate dehydrogenase (LDH) activity and superoxide anion-radical (SAR) scavenging activity. In this study, $K_2Cr_2O_7$ decreased the cell viability significantly in a dose-dependent manner, and the $XTT_{50}$ value was determined to be $37.5{\mu}M$, which was highly-toxic according to the Borenfreund and Puerner' toxic criteria. The antioxidant, butylated hydroxytoluene (BHT), increased remarkably the cell viability damaged by $K_2Cr_2O_7$-induced cytotoxicity in these cultures. With regard to the protective effect of the AP extract on $K_2Cr_2O_7$-induced cytotoxicity, AP extract produced a significant increase in cell viability and antioxidative effects as the inhibitory ability LDH and SAR scavenging ability. These findings suggest that oxidative stress is involved in the cytotoxicity of $K_2Cr_2O_7$, and the AP extract effectively protected the cells from $K_2Cr_2O_7$-induced cytotoxicity by antioxidative effects. These results suggest that natural resources, such as AP extract, may be a putative therapeutic agent for the diminution or treatment of cytotoxicity induced by heavy metallic bases, such as $K_2Cr_2O_7$ correlated with oxidative stress.