• 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.

• Toxicological Research
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• 제7권2호
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• pp.141-149
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• 1991

The treatment with 5ng/ml of mercuric chloride caused time-dependent decreases, and in the activities of GSH S-transferase and GSH-peroxidase, and in the concentration of GSH in CHO cells. Three hours after treatment of $Hg^{2+}$, the activity of GSH S-transferase was decreased to almost half value of control group and the activity of GSH-peroxidase was reduced significantly at 6 hr after treatment. The concentration of GSH was decreased 2 hr after treatment of $Hg^{2+}$ and was decreased to nearly half value of control group 3 hr after treatment.

• 한국식품영양과학회지
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• 제24권5호
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• pp.651-657
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• 1995

모유성분을 고분자분획(20KD 이상 분자)과 저분자분획(20KD 이하 분자)으로 나누어 항산화력을 검토한 결과, 고분자분획이 저분자분획 보다 더 강력한 항산화력을 나타내었다. 이 모유의 항산화력은 주로 20KD 이상에 존재하는 항산화 효소에 기인할 가능성이 시사되어 모유의 채유 기간에 따른 항산화 효소를 비롯하여 protein-SH와 nonprotein-SH를 검토한 결과, catatase는 7일째 현저히 저하한데 비해 GSH peroxidase, GSH S-transferase는 7일째를 전후로 현저히 증가한 후 감소하는 경향을 나타내었다. Protein-SH는 채유 기간에 따라 차츰 감소하였으나 nonprotein-SH는 20일째 peak를 이루고 그 후 감소하였다. 이상의 결과로 부터 모유의 고분자분획은 강력한 항산화력을 나타내었으며, 이 항산화력은 catalase, GSH peroxidase 및 GSH S-transferase 등의 항산화 효소 활성에 기인할 것으로 사료된다.

• 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.

• Journal of Yeungnam Medical Science
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• 제11권2호
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• pp.262-269
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• 1994

Cisplatin을 투여한 흰쥐의 간장 및 신장에서GSH의 역할을 관찰하고자 총 GSH의 농도, GSH peroxidase 및 GSH reductase이 효소활성도를 관찰하여 다음과 같은 결과를 얻었다. 총 GSH의 양(mM/g protein)은 간에서는 cisplatin을 투여한 군($1.51{\pm}0.28$)이 대조군(0.95+0.28)에 비해 현저히 증가하였으며 (p<0.01), 신장에서도 cisplatin 투여군(0$0.87{\pm}0.20$)이 대조군($0.60{\pm}0.14$)에 비해 유의하게 증가하였다(p<0.05). GSH peroxidase의 활성도(${\mu}M$ NADPH/mg protein/min)는 간장에서 cisplatin을 투여한 군($348.0{\pm}18.54$)이 대조군(415.5+53.15)에 비해 현저히 감소하였으며(p<0.01), 신장에서도 cisplatin 투여군($380.5{\pm}51.86$)이 대조군($327.2{\pm}20.36$)에 비해 유의하게 증가하였다(p<0.01). GSH reductase의 활성도(${\mu}M$ NADPH/mg protein/min)는 간장에서 cisplatin 투여군($3.09{\pm}0.88$)이 대조군(2.28+0.61)에 비해 현저히 증가하였으며(p<0.01), 신장에서도 cisplatin 투여군($3.30{\pm}1.01$)에 비해 cisplatin 투여군($8.50{\pm}2.62$)이 현저히 증가하였다(p<0.01). Cisplatin 투여로 인한 해독작용은 간에서는GSH의 양이 신장과 비교시 현저히 증가하였고 GSH reductase의 증가 및 GSH peroxidase의 감소로cisplatin해독에 GSH가 많이 이용되어 해독작용이 신장보다 더 잘 일어났으며 신장에서는 GSH가 증가하였으나 두 효소 모두 증가하였으므로 GSH가 일부 산화형으로 이용되어 간에서 보다는 해독작용이 적게 나타난 것으로 생각된다.

• Journal of Ginseng Research
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• 제20권2호
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• pp.173-178
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• 1996

Aerobic cells are normally protected from the damage of free radicals by antioxidative on , zymes such as superoxide dismutase (SOD), catalase, glutathione (GSH) peroxidase, GSH S- transferase and GSH reductase which scavenge free radicals as well as nonenzymatic antioxidants such as ceruloplasmin, albumin and nonprotein-SH including GSH. The effects of each component (ginsenoside $Rb_1$, $Rb_2$, Rc, Rd, Re, $Rb_1$, Rf, $Rh_1$ and $Rh_2$) of red ginseng on the antioxidative enzyme activities were investigated in the liver in order to screen antioxidative components of red ginseng. Ginsenoside $Rb_1$ and Rc showed a tendency to increase GSH peroxidase activity, while ginsenoside Rc significantly decreased Cu,Zn-SOD activity. Especially, ginsenoside $Rh_2$ significantly increased catalase activity. These results suggest that ginsenoside $Rh_2$ is an important active component among total saponins of red ginseng.

• Toxicological Research
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• 제9권2호
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• pp.159-166
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• 1993

The treatmene of V79 cells with diethyl maleate (DEM) led to decrease in glutathione (GSH) level as increasing DEM concentration. Mercuric chloride, treated for 6 hrs with 2ng/ml, affected the GSH metabolizing enzymes glutathione S-transferase (GST) and glutathione peroxidase (GSP), dropping their activities to 60% and 75%, respectively, though not so much in GSH level(80%). However, the toxic effects of mercuric chloride on those enzymes and GSH level were both amplified when the Hg2+ treatment was combined with the preceding DEM treatment.

• Journal of Nutrition and Health
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• 제33권7호
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• pp.733-738
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• 2000

The purpose of this study was to investigate the effects of green tea on gene expression of superoxide dismutase(SOD) and glutathione peroxidase(GSH-Px) in rat liver exposed to microwave. Sprague-Dawley male rats with 200$\pm$10g body weight were assigned to normal and microwave exposed groups : microwave exposed groups ; microwave exposed groups were divided two groups : microwave(MW) group which was administrated the distilled water and green tea(GT) group which was administrated the green tea extracts. The rats were irradiated with microwave at frequence of 2.45 GHz for 15 min and then the gene expression in the damaged tissue were investigated at 0.1, 3, 4,6 and 8 days after the microwave irradition to compared with the normal group. The level of SOD gene expression in MW group was lower than the normal group within 6 days but that of GT group as higher than MW group. These results may imply that green tea stimulates SOD expression and there by protecting tissues from free radicals. The GSH-Px gene was expressed a little bit lower than the normal group but that of GT group was expressed to higher lever than MW group from 4 days after irradiation. These results suggest that the administration of green tea extract may activate antioxidative gene expressions such as SOD and GSH-Px in rat and that may help to recover liver tissues from microwave damage by removing hazardous free radicals and oxidized by products from cells.

• 생명과학회지
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• 제10권5호
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• pp.475-483
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• 2000

Normally, aerobic cells are protected from the damage of free radicals by antioxidative enzymes such as catalase, superoxide dismutase (SOD), glutathione (GSH) peroxidase and GSH-S-transferase. In this study, we have investigate the effect of egg yolk protein hydrolysates on antioxidative activity and the activity of antioxidative enzyme in cultured hepatocytes (Chang). Without the pretreatment with hydrolysate, about 50% of the hepatocytes were killed within 2h by 225$\mu$M tert-butyl hydroperoxide (t-BHP). By contrast, fewer than 20% of the 5 K hydrolysate (permeate from 5 kDa membrane and not passed through 1 kDa membrane)-pretreated hepatocytes were killed by the same concentrations of t-BHP. In addition, the activities of catalase, GSH peroxidase and GSH-transferase were significantly increasing with the treatment of 5 K hydrolysate. These results suggest that 5 K hydrolysate exerts antioxidative effect by increasing activity of antioxidative enzymes.

• BMB Reports
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• 제33권6호
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• pp.514-518
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• 2000

Two open reading frames of Haemophilus influenzae, HI0572 and HI0751, showing homology to a yeast thioredoxin peroxidase II (TPx II) and an E. coli thiol peroxidase $P_{20}$, respectively, were cloned and expressed in E. coli, and then the proteins were subsequently purified and characterized. HI0751 protein showed the thioredoxin (Trx)-dependent peroxidase activity, whereas HI0572 protein showed glutathione-dependent peroxidase. The HI0572 is the first peroxiredoxin with glutathione peroxidase activity rather than thioredoxin peroxidase. Purified HI0572 and HI0751 proteins protected specifically the inactivation of glutamine synthetase by metal catalyzed oxidation (MCO) systems composed of $Fe^{3+}$, $O_2$ and mercaptans such as dithiothreitol, ${\beta}-mercaptoethanol$ and glutathione (GSH). Unlike the HI0751 protein, the HI0572 protein was more effective in protecting glutamine synthetase from inactivation by the $GSH/Fe^{3+}/O_2$ system. It seems that these unique properties of the HI0572 protein are due to the structure containing a glutaredoxin domain at it's C-terminal in addition to a peroxiredoxin domain.