• Archives of Pharmacal Research
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• v.18 no.3
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• pp.189-194
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• 1995

The focus of this study was to investigate the influences of enzymatic scavengers of active oxygen metabolites and phospholipase $A_2$ inhibitor on hepatic secretory and microsomal function during hepatic ischemia/reperfusion. Rats were pretreated with free radical scavengers such as superoxide dismutase (SOD), catalase, deferoxamine and phospholipase $A_2$ inhibitor such as quinacrine and then subjected to 60 min. no-flow hepatic ischemia in vivo. After 1, 5 hr of reperfusion, bile was collected, blood was obtained from the abdominal aorta, and liver microsomes were isolated. Serum aminotransferase (ALT) level was increased at 1 hr and peaked at 5 hr. The increase in ALT was significantly attenuated by SOD plus catalase, deferoxamine and quinacrine especially at 5 hr of reperfusion. The wet weight-to-dry weight ratio of the liver was significantly increased by ischemia/reperfusion. SOD and catalase treatment minimized the increase in this ratio. Hepatic lipid peroxidiltion was elevated by ischemia/reperfusion, and this elevation was inhibited by free radical scavengers and quina crine. Bile flow and cholate output, but not bilirubin output, were markedly decreased by ischemia/reperfusion and quinacrine restored the secretion. Cytochrome $P_{450}$ content was decreased by ischemia/reperfusion and restored by free radical scavengers and quinacrine to the level of that of the sham operated group. Aminopyrine N-demethylase activity was decreased and aniline p-hydroxylase was increased by ischemia/reperfusion. The changes in the activities of the two enzymes were prevented by free radical scavengers and quinacrine. Our findings suggest that ischemia/reperfusion diminishes hepatic secretory functions as well as microsomal drug metabolizing systems by increasing lipid peroxidation, and in addition to free radicals, other factors such as phospholipase $A_2$ are involved in pathogenes of hepatic dysfunction after ischemia/reperfusion.

• Proceedings of the Ginseng society Conference
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• 1990.06a
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• pp.45-48
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• 1990

Maltol(2-methyl-3-hydroxy-r-pyrone), a component known to be present in Korean Ginseng root showed an antioxidant action but its potency as an antioxidant was low; about 1150th that of other antioxidants such as p-phenylenediamine , BHA and BHT. However, maltol was able to protect the oxidation adamants in biological systems such as adriamycin-induced membrane damage in isolated cardiomyocytes, parquet-induced toxicities in isolated hepatocytes and repercussion injury in isolated hearts. The antioxidant action of maltol was also shown to be effective in vivo. The antioxidant action of this compound was probably due to the removal of hydroxyl radicals. In view of the roles of oxygen radical in various pathological processes, Korean Ginseng root, which contains several antioxidants including maltol, is expected to have beneficial efforts on the oxygen radical-involved processes. Keywords Maltol, Oxygen free radicals, Lipid preoccupation, Repercussion injury and Korean ginseng

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.9
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• pp.1330-1335
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• 2005

Red brownish p-pheylenediamine (PPD) has been widely used hair dye for women. The dye was known to cause systemic anaphylaxis, dermatitis and bladder cancer. But the effect of PPD toxicity with oxygen free radical has not been studied. This study investigated the degree of skin injury by PPD. PPD ($2.5\%$ PPD in $2\%\;NH_{4}OH$) was applied to the rat skin ($25 mg/16.5\;cm^2$) 3 or 5 times every other day. Histopathological findings demonstrated the proliferation of epithelial cells and the increased keratinization by PPD. The activities of glucose 6-phosphatase (G6Pase) was decreased and acid phosphatase (ACP) was increased in PPD-applied rat skin. Groups in which PPD was applied 5 times were more damaged than groups applied 3 times. To examine the relationship between tissue damage and oxygen free radicals, effect of PPD on xanthine oxidase (XO) activity was measured and XO activity was more significantly increased in the group treated with PPD 5 times than 3 times. However, reduced glutathione (GSH) content, and the activities of catalase (CAT), super-oxide dismutase (SOD) and glutathione S -transferase (GST) were more decreased in PPD-applied groups than in controls. Even though the activities of XOD was not changed in the group treated with PPD 3 times, the decreased activities of oxygen free radical system and the damaged skin tissue were observed. This result might be caused by the production of toxic PPD metabolites in rat skin. In conclusion, topical PPD application led to skin injury in a dose-dependent manner, probably due to the generation rate of oxygen free radical.

• Biomedical Science Letters
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• v.9 no.3
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• pp.151-158
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• 2003

In the biological world, there are a number of ecological fights for survival between each organism such as plants, animals and microorganism In such events, an organism can use its natural bioactive products as defence agent against other organisms. Furthermore, natural bioactive products can be utilized for medicine or functional food. Recently, we investigate the effect of Monascus pigment extracted from a fungus, Monascus anke, on the alcohol metabolism and blood lipid profile. In the present study, it is observed that Monascus pigment supplemented dietary may have a hepatoprotective effect on rat's liver damage induced with $CCl_4$ . By treatment with $CCl_4$(3 times, I.P), liver damage was reduced more in the rats fed 2% Monascus pigment extract supplemented diet than those fed standard diet, based on the serum levels of alanine aminotransferase, microsomal glucose-6-phosphatse activity and hepaic malondialdehyde content. On the other hand, oxygen free radical generating enzymes, hepatic P-450 dependent aniline hydroxylase, xanthine oxidase, and oxygen free radical scavenging enzymes, hepatic glutathione S-transferase, catalase, superoxide dismutase activities were generally higher both in $CCl_4$ treated group and control fed 2% Monascus pigment extract supplemented diet than those fed standard diet. In conclusion, the rats fed 2% Monascus pigment extract supplemented diet showed more reduced liver damage than those fed standard diet, which may be due to the acceleration of oxygen free radical metabolism.

• Journal of Ginseng Research
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• v.36 no.3
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• pp.256-262
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• 2012

Reactive oxygen species play critical role in kidney damage. Free radical-scavenging activities of Panax ginseng are known to be increased by heat-processing. The structural change of ginsenoside and the generation of Maillard reaction products (MRPs) are closely related to the increased free radical-scavenging activities. In the present study, we have demonstrated the Maillard reaction model experiment using ginsenoside Re and glycine mixture to identify the renoprotective effect of MRPs from ginseng or ginsenosides. Ginsenoside Re was transformed into less-polar ginsenosides, namely Rg2, Rg6 and F4 by heat-processing. The free radical-scavenging activity of ginsenoside Re-glycine mixture was increased in a temperature-dependant manner by heatprocessing. The improved free radical-scavenging activity by heat-processing was mediated by the generation of antioxidant MRPs which led to the protection of LLC-PK1 renal epithelial cells from oxidative stress. Although the free radical scavenging activities of less-polar ginsenosides were weak, they could protect LLC-PK1 cells from oxidative stress. Therefore, MRPs and less-polar ginsenosides contributed to the combined renoprotective effects against oxidative renal damage.

• Biomedical Science Letters
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• v.7 no.3
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• pp.99-102
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• 2001

Toluene is mainly metabolized in liver by oxidative pathway. Oxigen free radicals occur through the process of toluene metabolism Therefore it causes tissue and cell min by the oxygen free radicals from the metabolism of toluene. Melatonin acts as a highly efficient free radical scavenger that protects cells from damage by oxygen free radicals. To test this hypothesis, toluene hepatotoxicity was induced by an abdominal injection of toluene. To see if the melatonin protects the rat's liver, melatonin was administrated orally, at the time of each toluene injection. Aspartate aminotransferase(AST), alanin aminotransferase(ALT), latic dehydrogenase(LDH) and alkaline phosphatase(ALP) levels in serum were measured to estimate hepatic function. Malondialdehyde(MDA), which gives an indirect index of oxidative injury was also measured. Hippuric acid is the last metabolic Production of toluene was measured by HPLC. There were significantly higher in AST, ALT, LDH, MDA and hippuric acid in toluene group, but there were no significant difference in melatonin group except ALT and hippuric acid. There was significantly lower in ALP level in toluene group, but there was no significant difference melatonin group, suggesting a significant hepatotoxicity due to oxygen free radicals through the process of toluene metabolism Melatonin treatment significantly protected hepatic function and free radical-mediated injury in the liver against toluene-induced changes. Accordingly, this study shows that melatonin is helpful in protecting liver injury by acute toluene intoxication.

• Preventive Nutrition and Food Science
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• v.5 no.2
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• pp.105-108
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• 2000

To evaluate an effect of oxygen free radical on the toluence metabolism, the rats were fed on a tungstate sup-plemented diet(0.75g of tungstate included in 1kg of standard diet) or a standard diet. To the present xanthine oxidase deficient animal model, toluene(0.15ml/100g of body weight) was injected and then the animals were sacrificed after 24 hrs to determine the toluene metabolizing enzyme activities and toluene metabolite, hippuric acid concentration. The increasing rate of urinary hippuric acid concentration was significantly(p<0.01) higher in tungstate fed animals than in standard diet fed ones. Hepatic cytochrome P_450 contents were significantly higher(p<0.01) in tungstate fed animals than in standard diet fed ones. And tungstate fed animals showed a ten-dency of higher activities of benzylalcohol dehydrogenase while a significantly higher activites of benzaldehyde dehydrogenase (p<0.01) than standard diet fed animals. In conclusion, the more possibly reduced oxygen free radical in toluene-treated rats fed with a tungstate supplemented diet than in those fed with a standard diet would be responsible for the enhancement of toluene metabolism.

• Environmental Mutagens and Carcinogens
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• v.19 no.2
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• pp.116-121
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• 1999

Quercetin and its glycosides showed a strong free radical scavenging effect to DPPH radical generation. However, there were not big differences between quercetin aglycone and glycosides under experimental condition of this study. On the other hand, quercetin had pro-oxidant effect in bleomycin-dependent DNA assay. Quercetin aglycone and its glycosides, quercitrin inhibited $H_2$$O_2$- induced DNA damage in CHL cells. They also have an anticlastogenicity toward DNA breakage agent by radical generation like bleomycin. These results indicate that quercetin aglycone and its glycosides are capable of protecting the free radical generation induced by reactive oxygen species like $H_2$$O_2$. The mechanism of inhibition in hydrogen peroxide-induced genotoxicity may be due to their free radical scavenging properties. Therefore, quercetin aglycone and its glycosides may be useful chemopreventive agents by protecting of free radical generation which are involved in carcinogenesis and aging. However, quercetin and its glycosides must also carefully examined for pro-oxidant properties before being proposed for use in vivo.

• Environmental Analysis Health and Toxicology
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• v.18 no.3
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• pp.165-174
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• 2003

Cr (Ⅵ) - containing compounds are well-established carcinogens, although the mechanism for chromium - induced carcinogenesis is still not well understood. The reduction of Cr (Ⅵ) to its lower oxidation states, par ticularly Cr (V) and Cr (IV), is an important step for the production of chromium-mediated reactive oxygen species (ROS). The persistent oxidative stress during the reduction process may play a key role in the mechanism of Cr (Ⅵ) -induced carcinogenesis. This paper summarizes recent studies on (1) the reduction of Cr (Ⅵ) to Cr (III) occur by a multiplicity of mechanisms depending on the nature of reducing agents including ascorbate, diol-and thiol-containing molecules, certain flavoenzymes, cell organelles, intact cells, and whole animals; (2) free-radical production with emphasis on hydroxy radical generation via Fenton or Haber-Weiss type reactions; and (3) free radical - induced cellular damage, such at DNA strand breaks, hydroxylation of 2'-deoxyguanosine, and activation of nuclear transcription factor kB.

• Preventive Nutrition and Food Science
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• v.14 no.4
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• pp.277-282
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• 2009

The antioxidant potency of methanolic extract of Duchesnea indica (MDI; Indian strawberry) was investigated by employing various established in vitro systems, such as total phenolic content, 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, reducing power assay, metal chelating assay, superoxide radical scavenging activity and protective ability of DNA damage and protein oxidation. MDI inhibited metal chelating by 75.57% at 2 mg/mL, scavenged 50% DPPH free radical at 29.13 ${\mu}$g/mL, and eliminated approximately 46.21% superoxide radical at the concentration of 1 mg/mL. In addition, MDI showed strong ability on reducing power, DNA damage protection and protein oxidation protection. Overall, results suggested that MDI might be beneficial as a potent antioxidant and effectively employed as an ingredient in food applications.