• BMB Reports
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• 제38권2호
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• pp.232-237
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• 2005

A glutathione S-transferase (GST) from Lactuca sativa was purified to electrophoretic homogeneity approximately 403-fold with a 9.6% activity yield by DEAE-Sephacel and glutathione (GSH)-Sepharose column chromatography. The molecular weight of the enzyme was determined to be approximately 23,000 by SDS-polyacrylamide gel electrophoresis and 48,000 by gel chromatography, indicating a homodimeric structure. The activity of the enzyme was significantly inhibited by S-hexylGSH and S-(2,4-dinitrophenyl) glutathione. The enzyme displayed activity towards 1-chloro-2,4-dinitrobenzene, a general GST substrate and high activities towards ethacrynic acid. It also exhibited glutathione peroxidase activity toward cumene hydroperoxide.

• Nutrition Research and Practice
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• 제4권2호
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• pp.114-120
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• 2010

The effects of grape seeds extract and grape peels extract prepared from grape pomace on the activity of antioxidant enzymes, degree of lipid peroxidation in serum and liver tissue were investigated in rabbits fed on high cholesterol diet. New Zealand white rabbits were divided as follows ; 1) NOR (normal group); 2) CHOL (cholesterol group); 3) GSH (cholesterol + grape seed extract group); 4) GPE (cholesterol + grape peel extract); 5) GSP (cholesterol + grape seed powder); 6) GPP (cholesterol + grape peel powder); 7) GE (cholesterol + grape seed and peel extract); 8) GP (cholesterol + grape seed and peel powder). Eight groups of rabbits were studied for 8 weeks. At the end of the experimental period, rabbits were sacrificed and the liver tissue were removed. Then, GSH, GPx, GST, CAT and MDA in the liver were measured. In liver tissues, total glutathione contents (GSH), glutathione peroxidase (GPx) and catalase (CAT) activity, which was significantly higher by grape seed extract supplementation. The level of malondialdehyde (MDA) was lower in the serum of rabbits fed grape seed extract or grape peel powder plus cholesterol than in the serum of rabbits fed cholesterol alone. It is therefore likely that grape seed extract prepared from grape pomace functioned as antioxidants in vivo, negating the effects of the oxidative stress induced by 1% cholesterol diet. The grape seed extract was found effective in converting the oxidized glutathione into reduced glutathione, and in removing $H_2O_2$ that is created by oxidative stress. The grape peel powder was found to have small influence on reduced glutathione content, CAT and GPX activity, but it increased GST activity in liver tissues, resulting in promoting the combination of lipid peroxide and glutathione (GSH), and further, lowering the formation of lipid peroxide in the serum. Therefore, grape pomace (grape seed extract and grape peel powder) supplementation is considered to activate the antioxidant enzyme system and prevent damage with hypercholesterolemia.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Signal transduction in Toxicology
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• pp.161-161
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• 2001

Phospholipid hydroperoxide glutathione peroxidase (PHGPx) is an antioxidant selenoenzyme which interacts directly with and diminishes peroxidized phospholipids, cholesterol and cholesteryl ester in tissues. PHGPx activity appears in most tissues, but is especially high in testis. In testis, PHGPx level decreases in hypophysectomized rats but is partially restored after gonadotropin treament.(omitted)

• 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.

• BMB Reports
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• 제34권3호
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• pp.278-283
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• 2001

Antioxidant and redox enzyme activities are known to be involved in the cellular responses to various stresses. Their variations were observed according to the growth cycle of the fission yeast Schizosaccharomyces pombe. Peroxidase activity appeared to be notably higher in the early exponential phase than in the mid-exponential and stationary phases. However, catalase activity showed a variation pattern resembling the growth curve. Glutathione S-transferase activity was higher in the early exponential and late stationary phases. Activities of the two redox enzymes, thioredoxin and thioltransferase (glutaredoxin), were high in the stationary phase. However, their activities appeared to increase from the early exponential to mid-exponential phase. Total glutathione content had a varying pattern similar to that of thioredoxin and thioltransferase. However, its content in the early exponential phase was high. These results propose that antioxidant and redox enzymes tested are also involved in the mechanism of cell growth.

• Journal of Community Nutrition
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• 제2권2호
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• pp.164-169
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• 2000

The purpose of this study was to examine the effect of taurine supplementation time on the activity of the enzymes metabolizing lipid peroxide in the liver of streptozotocin(STZ)-induced diabetic rats, Sprague-Dawley male rats were fed the purified diet for 7 weeks. They were supplemented with or without 1% taurine in drinking water before or after STZ injection or during all experimental procedure. In comparison to diabetic group without taurine, glucose-6-phosphatase(G6Pase) activity was decreased in diabetic group supplemented with taurine before STZ injection, and it was increased in diabetic group supplemented with taurine after STZ injection, but the difference was not significant. Glutathione S-transferase(GST) activity was significantly increased by the injection of STZ. However, the GST activities of diabetic groups exposed to taurine after STZ injection or during all experimental procedure were significantly decreased. Glutathione peroxidase(GPx) activities was significantly decreased by STZ injection. However, only in diabetic group supplemented with taurine before STZ injection, GPx activities was not decreased by the STZ injection. These results suggest that taurine supplementation may change the activities of GSH-related enzymes metabolizing lipid peroxide in the liver of streptozotocin(STZ)-induced diabetic rats and that may be helpful for the prevention of diabetic complication.

• Journal of Ginseng Research
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• 제41권3호
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• pp.307-315
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• 2017

Background: Red-skin root disease has seriously decreased the quality and production of Panax ginseng (ginseng). Methods: To explore the disease's origin, comparative analysis was performed in different parts of the plant, particularly the epidermis, cortex, and/or fibrous roots of 5-yr-old healthy and diseased red-skin ginseng. The inorganic element composition, phenolic compound concentration, reactive oxidation system, antioxidant concentrations such as ascorbate and glutathione, activities of enzymes related to phenolic metabolism and oxidation, and antioxidative system particularly the ascorbate-glutathione cycle were examined using conventional methods. Results: Aluminum (Al), iron (Fe), magnesium, and phosphorus were increased, whereas manganese was unchanged and calcium was decreased in the epidermis and fibrous root of red-skin ginseng, which also contained higher levels of phenolic compounds, higher activities of the phenolic compound-synthesizing enzyme phenylalanine ammonia-lyase and the phenolic compound oxidation-related enzymes guaiacol peroxidase and polyphenoloxidase. As the substrate of guaiacol peroxidase, higher levels of $H_2O_2$ and correspondingly higher activities of superoxide dismutase and catalase were found in red-skin ginseng. Increased levels of ascorbate and glutathione; increased activities of $\text\tiny L$-galactose 1-dehydrogenase, ascorbate peroxidase, ascorbic acid oxidase, and glutathione reductase; and lower activities of dehydroascorbate reductase, monodehydroascorbate reductase, and glutathione peroxidase were found in red-skin ginseng. Glutathione-S-transferase activity remained constant. Conclusion: Hence, higher element accumulation, particularly Al and Fe, activated multiple enzymes related to accumulation of phenolic compounds and their oxidation. This might contribute to red-skin symptoms in ginseng. It is proposed that antioxidant and antioxidative enzymes, especially those involved in ascorbate-glutathione cycles, are activated to protect against phenolic compound oxidation.

• Tuberculosis and Respiratory Diseases
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• 제41권3호
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• pp.222-230
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• 1994

연구배경 : Paraquat는 광범위 제초제로서 널리 사용하고 있으나, 중독시 치명적인 중독 증상을 일으킨다. 특히 폐에서는 진행성 불가역성 폐섬유종을 일으키는데, 이의 기전으로 산소유리기와 관계가 있으나 아직은 생화학적 기전이 명확하지 않다. paraquat에 의한 산소유리기가 생기면 glutathione의 변화와 G6PDH, SOD, catalase 및 glutathione peroxidase등의 효소 활성의 변화가 생길 것으로 생각되며, 특히 catalase가 많이 관여할 것으로 생각되어진다. 방법 : Catalase 억제제인 aminotriazole을 사용하여 paraquat만 쓰는 것과 paraquat와 aminotriazole을 같이 투여할때 생쥐의 생존율을 알아보고, 실험군을 정상대조군, Group A(aminotriazole투여군), Group B(paraquat 투여군), Group C(paraquat와 amino-triazole 병합투여군) 4군으로 나누어 폐조직에서 glutathione량, G6PDH, SOD, catalase 및 glutathione peroxidase활성도를 측정하여 비교했다. 결과 : Paraquat와 aminotriazole 병합 투여군의 생존율이 paraquat투여군보다 현저히 감소하였고, paraquat 투여로 인하여 폐 glutathione량은 정상대조군에 비해 20%정도 감소 되었으나, aminotriazole의 투여로 인한 폐 glutathione량의 변화는 없었다. Paraquat투여로 폐 SOD, catalase 및 glutathione peroxidase활성이 모두 유의한 감소를 나타냈는데, 특히 catalase가 가장 큰 효소활성 감소를 나타냈으며, paraquat와 aminotriazole병합투여군에서는 catalase와 glutathione peroxidase활성이 paraquat단독투여군에 비하여 유의한 효소활성감소를 나타냈고, SOD는 효소활성의 변화가 감지되지 않았다. 결론 : Paraquat투여시 catalase활성이 유의하게 감소되는 점으로 보아 paraquat독성이 catalase활성과 밀접하게 연관되는 것으로 사료되며, 또한 paraquat의 독성이 aminotriazole의 병합 투여로 더욱 증가되어 나타나는데, 이러한 결과는 aminotriazole투여로 catalase활성의 감소가 크게 나타나나 glutathione량의 변화는 없는 점으로 보아 aminotriazole투여에 의한 paraquat독성의 증가는 총 폐 glutathione량의 변화에 의한 영향보다는 catalase활성감소에 의한 결과로 생각된다. Paraquat와 aminotriazole를 병합 투여하여 catalase활성이 억제되면 증가된 과산화수소로 hydroxyl radicals이 생성되고, 이에 의한 폐 세포손상이 유발되어 나타나는 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제14권2호
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• pp.170-173
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• 2001

The objective of this study was to investigate the effect of selenium (Se) on in vitro development of bovine embryos. In CR1BSA, FBS-free medium, the bovine embryos could not proceed past the developmental block more efficiently to morula stage than in chemically undefined media. Addition of glutathione precursor, cysteine, with $\beta$-mercaptoethanol did not improve the development in chemically defined medium and neither did glutathione alone. Exogenous selenium improved the embryonic development to the morula and blastocyst stages at 6 days post-insemination (dpi) significantly (67.1% vs 57.5%, p<0.05), and blastocyst stage at 8 dpi (30.1% vs 20.5%, p>0.05). These improvements might be induced by elevated glutathione peroxidase activity due to addition of Se, and a possible mechanism of selenium to elevate the activity of glutathione peroxidase is discussed.

• 한국식품영양과학회지
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• 제27권1호
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• pp.149-156
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• 1998

The purpose of this study was to investigate the effects of vitamin E supplementation on the activities of antioxidative enzymes in liver of KK mice of various ages and various duration of diabetes. Diabetes was induced by feeding high fat diet containing 20% corn oil(wt/wt). Weaned KK mice were fed high fat diet containing 51 IU or 2080 IU vitamin E per kg diet. Animals were sacrificed at 4, 6, and 9 months of age. In nondiabetic group, we found the decrease of antionxidative enzyme activities with aging. In diabetic group, antioxidative enzyme activities were decreased, and the change of hepatic vitamin E was related to glutathione peroxidase activity (r=0.71, p<0.001). Treatment with vitamin E did not modify the level of fasting blood glucose. However, it was observered that glutathione reductase and glutathione peroxidase activities as well as hepatic glutathione levels were increased by vitamie E supplementation, whereas catalase activity did not changed. The present result suggest that high vitamin E supplementation protects against lipid peroxidative damage in diabetic KK mice.