• 대한약침학회지
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• 제10권1호통권22호
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• pp.121-135
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• 2007

Objectives : This study was carried out to examine protective effect of wild ginseng extract on HepG2 human hepatoma cell line against tert-Butyl hydroperoxide (t-BHP)-induced oxidative damage. Methods : To evaluate protective effect of wild ginseng extract against t-BHP induced cytotoxicity, LDH level and activity of glutathione peroxidase and reductase were measured. Gene expression was also measured using DNA microarray. Results : Wild ginseng extract showed a significant protective effect against t-BHP-induced cytotoxicity in HepG2 cell line. It is not, however, related with the activities of glutathione peroxidase and glutathione reductase. Analysis of gene expression using DNA chip, demonstrated that 28 genes were up-regulated in t-BHP only group. Five genes - selenoprotein P, glutathione peroxidase 3, sirtuin 2, peroxiredoxin 2, serfiredoxin 1 homolog - may be related with the protective effect of wild ginseng extract. Conclusions : Based on the results, a protective effect of wild ginseng extract against t-BHP-induced oxidative damage in HepG2 cell line is not associated with the activities of glutathione peroxidase and glutathione reductase, but with the expression of selenoprotein P, glutathione peroxidase 3, sirtuin 2, peroxiredoxin 2, and serfiredoxin 1 homolog.

• 환경생물
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• 제29권4호
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• pp.258-264
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• 2011

Glutathione (GSH)은 직접적으로 활성산소종을 제거하거나 GSH peroxidase와 같은 활성산소종 제거 효소의 조효소로써, 산화적 스트레스로부터 세포를 방어하는 데 중요한 역할을 한다. GSH peroxidase는 두 분자의 GSH을 이용해 세포 내 과산화수소를 물로 전환한다. $N$-acetyl-L cysteine (NAC)는 항산화제 중 하나로 세포 내 GSH의 전구물질로 이용된다. 본 연구는, 0mM에서 20mM의 NAC 단독 처리 또는 100 Gy 감마선과 복합 처리한 효모세포에서 GSH peroxidase를 코드화(encoding)하는 유전자인 $GPX1$과 $GPX2$의 전사적 발현을 통해 GSH, NAC와 GSH peroxidase의 연관성을 알아보았다. $GPX1$과 $GPX2$의 전사적 발현은 NAC와 100 Gy 감마선에 의해 유도되었다. 조사된 효모세포에서 NAC의 증가 농도에 따라 GSH peroxidase 두 유전자의 발현은 감소되었다. 이러한 결과로, NAC에 의해 증가된 세포 내 GSH는 GSH peroxidase 유전자의 전사적 발현을 유도하며, NAC는 감마선으로부터 생성된 활성산소종 직접적 제거와 GSH peroxidase 유전자의 전사적 발현을 유도함으로써 세포를 보호할 수 있다는 것이 밝혀졌다.

• Preventive Nutrition and Food Science
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• 제8권1호
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• pp.36-39
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• 2003

Many defined cell culture media were formulated over 3() years ago and may be deficient in certain micronutrients whose essentiality has only subsequently been recognised. The objective of this study was to evaluate whether alpha-minimal essential medium (MEM) supplemented with 10% foetal bovine serum contained sufficient selenium for optimal activity of the selenium containing enzymes cytosolic glutathione peroxidase (cGPx) and phospholipid hydroperoxide glutathione peroxidase (PHGPx) in cultured Chinese hamster ovary (CHO) cells. Additionally, the effect of zinc deficiency and metallothionein (MT) overexpression on cGPx and PHGPx activity was studied. The addition of 100 nM of selenous acid to the culture medium increased cGPx expression by 10-fold and PHGPx by about 2-fold in both wild-type CHO-K1 cells and CHO-K1 cells overexpressing mouse MT-1. Zinc deficiency had no significant effect on enzyme activity, but cells overexpressing mouse MT-1 had higher levels of cGPx activity. Zinc deficiency decreased cell survival but overexpression of MT-1 was partially protective, probably because its presence in quantity favoured the uptake, sequestration and cellular retention of any remaining zinc. This study demonstrates that selenium in complete alpha-MEM is insufficient for optimal cGPx and PHGPx activity and may compromise the cellular response to oxidative stress.

• Journal of Nutrition and Health
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• 제30권9호
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• pp.1061-1066
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• 1997

This study was undertaken to evaluate the effect of 4 weeks of $\alpha$-tocopherol(800 I.U./d) supplementation on oxidant stress of eleven female aerobic -majoring students during rest and exercise. Changes in the activity of the antioxidant enzyme glutathione peroxidase were also studied. Serum $\alpha$-tocopherol concentration was significantly increased with vitamin E supplementation(710.1$\pm$113.8$\mu\textrm{g}$/dl vs. 1,485,8$\pm$105.2$\mu\textrm{g}$/dl). In addition, serum MDA concentration, an index of lipid peroxidation, significantly decreased after vitamin E supplementation. However, MDA values after exercise increased to pre-supplementation levels. Serum glutathione peroxidase activity significantly increased with vitamin E supplementation. The enzyme activity showed a trend toward decrease after exercise. Serum cholesterol values were not significantly affected by vitamin E supplementation. However, serum triglycerides significantly increased after supplementation against oxidative stress during resting periods. These supplements appraently work by decreasing lipid peroxidation and increasing glutathione peroxidase activity. However, vitamin E supplementation did not prevent exercise-induced increases in lipid peroxidation.

• 대한수의학회지
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• 제31권1호
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• pp.41-47
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• 1991

The protective of influences of sodium selenitc ($Na_2SeO_3$) against the methemoglobinemia with sodium nitrite were investigated on hemoglobin, methemoglobin, glutathione peroxidase and NADH-methemoglobin reductase activity in rabbits which were given 0,1,3 and 9ppm sodium selenite of drinking water for a week. Dietary selenium did not alter total hemoglobin in the blood of rabbits. Selenium was found to decrease nitrite-induced methemoglobin in a dose-dependent manner. The glutathione peroxidase activity was also increased by selenium in all the experimental groups. However, the NADH-methemoglobin reductase activity by selenite did not show significant differences as concerns the methemoglobinemia. These results showed that selenium could inhibit nitrite-induced methemoglobinemia. Its influence of inhibition is suggested that the effect of the reduction of methemoglobin was greatly stimulated by glutathione peroxidase activity.

• 대한한방내과학회지
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• 제21권1호
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• pp.108-115
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• 2000

Objective : To investigate the hepatoprotective effects of Gami-oryungsan on the liver damage induced by bromobenzene. Method : The development of fibrosis and acute liver injury was examined by the chemical analysis of AST, AL T, ${\gamma}$-GTP . and epoxide hydrolase glutathione S-transferase glutathione peroxidase enzyme activity, lipidoperoxide levels, glutathione levels were measured and oberved. Results : The increasing levels of lipidoperoxide was decreased proportionally according to dose of extract GO. Epoxide hydrolase glutathioneS-transferase glutathione peroxidase enzyme activity highly increased in GO pre-acupunctured group compared with the group treated with only bromobenzene. The increase of serum AST, AL T, ${\gamma}$-GTP enzyme activity of mice by bromobenzene was inhibited by the administration of GO. Lipidoperoxide levels in rat's liver decreased compared to the case of bromobenzene-treated group. The levels of Glutathione decreased by bromo benzene were increased highly in GO pre-acupunctured group. Conclusion : These results suggest that GO extract recovers the damage of liver due to bromobenzene intoxication by decreasing the lipid peroxidation AST AL T ${\gamma}$-GTP enzyme activity and increasing epoxide hydrolase glutathioneS-transferase glutathione peroxidase enzyme activity, glutathione levels.

• Tuberculosis and Respiratory Diseases
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• 제44권1호
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• pp.104-113
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• 1997

연구배경 : 호기성 생물에서 산소의 대사과정 중에 산소의 불안전한 환원으로 산소유리기가 생성되는데 이들 산소유리기의 현저한 증가시 페손상 등 임상적으로 중요한 독성을 일으킬 수 있다고 5 알려져 있어 증가된 산화물이 여러 형태로 만성폐쇄성 폐질환의 발생에 관여 할 것으로 생각된다. 산소유리기의 폐손상과 이에 대한 항산화효소의 방어효과 및 활성도 변화를 관찰함으로 만성폐쇄성 폐질환의 병태생리의 일부분을 알 수 있겠다. 방법 : 만성폐쇄성 폐질환 환자군과 정상대조군 각 15명의 혈청과 적혈구에서 thiobarbituric acid reactant 변화와 항산화효소들(superoxide dismutase, glutathione peroxidase, catalase)의 활성도, 그리고 glutathione의 sulfhydry1기 를 측정하여 비교하였다. 결과 : Thiobarbituric acid reactant는 만성폐쇄성 폐질환 환자군에서 정상대조군보다 혈청과 적혈구에서 모두 유의한 증가를 보였고, superoxide dismutase활성도는 두 군사이에 유의한 차이가 없었으나, glutathione peroxidase와 catalase활성도는 만성폐쇄성 폐질환군에서 정상대조군보다 유의하게 감소되었다. 그리고 총 sulfhydryl기와 비단백 sulfhydryl기 모두 혈청과 적혈구에서 유의한 차이가 없었다. 결론 : 만성폐쇄성 폐 질환 환자에서 thiobarbituric acid reaclant의 증가를 보인 것은 산소유리기에 의한 세포손상을 나타내며, 항산화효소들중 superoxide dismutase는 큰 차이가 없었으나 glutathione peroxidase, catalase등은 대조군에 비해 유의하게 감소하여 만성폐쇄성 폐질환 환자에서 glutathione peroxidase 와 catalase 감소가 세포손상 기전의 한부분으로 작용한 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제31권1호
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• pp.79-91
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• 2021

γ-Glutamylcysteine synthetase (Gcs1) and glutathione reductase (Glr1) activity maintains minimal levels of cellular methylglyoxal in Candida albicans. In glutathione-depleted Δgcs1, we previously saw that NAD(H)-linked methylglyoxal oxidoreductase (Mgd1) and alcohol dehydrogenase (Adh1) are the most active methylglyoxal scavengers. With methylglyoxal accumulation, disruptants lacking MGD1 or ADH1 exhibit a poor redox state. However, there is little convincing evidence for a reciprocal relationship between methylglyoxal scavenger genes-disrupted mutants and changes in glutathione-(in)dependent redox regulation. Herein, we attempt to demonstrate a functional role for methylglyoxal scavengers, modeled on a triple disruptant (Δmgd1/Δadh1/Δgcs1), to link between antioxidative enzyme activities and their metabolites in glutathione-depleted conditions. Despite seeing elevated methylglyoxal in all of the disruptants, the result saw a decrease in pyruvate content in Δmgd1/Δadh1/Δgcs1 which was not observed in double gene-disrupted strains such as Δmgd1/Δgcs1 and Δadh1/Δgcs1. Interestingly, Δmgd1/Δadh1/Δgcs1 exhibited a significantly decrease in H2O2 and superoxide which was also unobserved in Δmgd1/Δgcs1 and Δadh1/Δgcs1. The activities of the antioxidative enzymes erythroascorbate peroxidase and cytochrome c peroxidase were noticeably higher in Δmgd1/Δadh1/Δgcs1 than in the other disruptants. Meanwhile, Glr1 activity severely diminished in Δmgd1/Δadh1/Δgcs1. Monitoring complementary gene transcripts between double gene-disrupted Δmgd1/Δgcs1 and Δadh1/Δgcs1 supported the concept of an unbalanced redox state independent of the Glr1 activity for Δmgd1/Δadh1/Δgcs1. Our data demonstrate the reciprocal use of Eapx1 and Ccp1 in the absence of both methylglyoxal scavengers; that being pivotal for viability in non-filamentous budding yeast.

• Preventive Nutrition and Food Science
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• 제4권2호
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• pp.134-138
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• 1999

The effects of dietary Coix(lacryma-jobi) water extract on the antioxidant enzyme activity in the liver and kidney of Sprague-Dawley rats were studied. Forty-five rats were fed for 3 weeks with either control diet or experimental diets that contain either Coix water extract or Coix water residue. Twenty percent of the carbohydrate was replaced with Coix water residue by dry weight in the water residue diet, while distilled water was replaced by Coix water extract to make a pellet-form diet in the Coix water extract diet. The levels of glutathione, glutathione-peroxidase, and glutathione-S-transferase activities in liver and kidney were measured . It has been found that glutathione, glutathione peroxidase, and glutathione-S-transferase enzyme activities from activities from liver and kidneyof the rats were enhanced in the group fed with Coix water extract.

• The Korean Journal of Physiology and Pharmacology
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• 제1권2호
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• pp.221-224
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• 1997

Effects of melatonin on hepatic glutathione-peroxidase (GSH-Px) and glutathione-reductase (GSH-reductase) activities were studied in Sprague-Dawley (SD) rats administered i.p. (10 mg/kg body weight) with melatonin during 15 days. The activity of cytosolic GSH-reductase in the liver was not changed by melatonin. However, melatonin injection increased significantly the activity of liver cytosolic GSH-Px activity compared with those in saline-treated rats. At the same time, plasma GSH-Px was also increased significantly in melatonin-treated rats. Since GSH-Px, a major antioxidative enzyme, removes $H_2O_2$ and lipid peroxides which are formed during lipid peroxidation from cellular membrane, such elevation of heptatic GSH-Px activity may contribute to the improvement of antioxidative effects under oxidative damage in the liver.