• 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.

• Archives of Pharmacal Research
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• 제28권9호
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• pp.1065-1072
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• 2005

The nascent thyroglobulin (Tg) multimer molecule, which is generated during the initial fate of Tg in ER, undergoes the rapid reductive depolymerization. In an attempt to determine the depolymerization process, various types of Tg multimers, which were generated from deoxy­cholate-treated/reduced Tg, partially unfolded Tg or partially unfolded/reduced Tg, were subjected to various GSH (reduced glutathione) reducing systems using protein disulfide isomerase (PDI), glutathione reductase (GR), glutaredoxin or thioredoxin reductase. The Tg multimers generated from deoxycholate-treated/reduced Tg were depolymerized readily by the PDI/GSH system, which is consistent with the reductase activity of PDI. The PDI/GSH-induced depolymerization of the Tg multimers, which were generated from either partially unfolded Tg or partially unfolded/reduced Tg, required the simultaneous inclusion of glutathione reductase, which is capable of reducing glutathionylated mixed disulfide (PSSG). This suggests that PSSG was generated during the Tg multimerization stage or its depolymerization stage. In particular, the thioredoxin/thioredoxin reductase system or glutaredoxin system was also effective in depolymerizing the Tg multimers generated from the unfolded Tg. Overall, under the net GSH condition, the depolymerization of Tg multimers might be mediated by PDI, which is assisted by other reductive enzymes, and the mechanism for depolymerizing the Tg multimers differs according to the type of Tg multimer containing different degrees and types of disulfide linkages.

• 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.

• 생명과학회지
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• 제6권1호
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• pp.48-55
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• 1996

Oxygen free radicals are highly reactive molecules with unpaired electrons, which are produced with in aerobic cells in the course of normal metabolic events. Normally, aerobic cells are protected from the damage of free radicals by antioxidative enzymes such as superoxide dismutase (SOD), catalase, glutathione (GSH) peroxidase, GSH S-transferase and GSH reductase which scabvenge free radicals as well as nonenzymatic antioxidants such as ceruloplasmin, albumin and nontioxidants in order to elucidate antioxidative mechanisms of red ginseng. The treatment with total saponin of red ginseng significantly devreased the contents of malondialdehyde and total free radicals in the liver. On the other hand, total saponin of red ginseng significantly increased the activities of SOD, catalase and GSH reductase and nonprotein-SH level. These results suggest that total saponin of red ginseng exerts an antioxidative effect by increasing endogenous antioxidants.

• Korean Journal of Acupuncture
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• 제20권1호
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• pp.39-43
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• 2003

괴화약침액이 간세포의 quinone reductase, glutathione S-transferase 와 환원형 glutathione의 활성에 미치는 영향을 살펴 본 결과 괴화약침액은 암예방 효소인 Phase II enzyme을 유의성 있게 증가 시켰다. 따라서 괴화약침액은 암예방에 효과가 있는 것으로 사료된다.

• 생약학회지
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• 제32권4호통권127호
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• pp.269-273
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• 2001

Ethanol extracts from Xanthii Fructus (XFE) and Prunellae Spica (PSE) were investigated for the effects on the induction of cancer chemoprevention-associated enzymes. The following effects were measured: (a) induction of quinone reductase (QR) (b) induction of glutathione S-transferase (GST) (c) reduced glutathione (GSH) level. XFE and PSE were potent inducers of quinone reductase activity in Hepa1c1c7 murine hepatoma cells. Glutathione levels were increased with XFE and PSE. In addition, glutathione S-transferase activity was increased with XFE. However, GST activity was not increased with PSE. These results suggest that XFE and PSE have chemopreventive potentials by inducing quinone reductase and increasing GSH levels.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2003년도 정기총회 및 학술발표회
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• pp.61-61
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• 2003

We have cloned the CGR1 gene encoding glutathione reductase (GR) which catalyzes the reduction of oxidized glutathione (GSSG) to reduced glutathione (GSH) from Candida albicans. The cgr1/cgr1 mutants were not viable when CaMAL2 promoter repressed the CGR1 expression. The growth of the mutants could be partially overcome by thiol compounds such as GSH, dithiothreitol, cysteine, N-acetylcysteine and GSSG. Interestingly, C. albicans with CGR1 overexpressed showed defective hyphal growth on solid medium and attenuated virulence. We have also cloned the GCS1 gene encoding ${\gamma}$-glutamylcysteine synthetase which catalyzes the first step of glutathione biosynthesis. The gcs1/gcs1 mutants were nonviable in minimal defined medium. The growth of the mutants could be resumed by supplementing with GSH, GSSG and ${\gamma}$-glutamylcysteine in the medium. The mutants had increased intracellular D-erythroascorbic acid level up to 2.25-fold when transferred to GSH-free medium. When the mutants were depleted of GSH, they showed typical markers of apoptosis. In conclusion, these results suggest that glutathione is an essential metabolite, and involved in hyphal growth, virulence and apoptosis in C. albicans.

• Korean Journal of Acupuncture
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• 제18권1호
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• pp.21-26
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• 2001

발암물질을 무독화시키는 QR 생성 유도를 살펴보기 위하여 황기 약침액 및 열수추출액을 생쥐의 간암세포인 Hepa1c1c7에 처리하여 측정한 결과, 황기 약침액의 농도를 증가시킬수록 많은 QR 생성율을 보였으며, GSH 생성이 증가하였고, GST 생성 또한 증가하였다.

• 생약학회지
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• 제30권3호
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• pp.261-268
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• 1999

Lonicerae flos aqua-acupuncture solution (LFAS) and Lonicerae flos water-extracted solution (LFWS) were prepared and tested for chemopreventive potentials. Three biomarkers [quinone reductase (QR), ornithine decarboxylase (ODC), glutathione(GSH)] were used to test chemopreventive potential of LFAS. LFAS was potent inducer of QR activity in Hepa1c1c7 murine hepatoma cells, whereas LFWS is less potent. LFAS and LFWS were also induced QR activities in cultured human hepatoma Hep3B cells. The effect of LFAS and LFWS were tested on the growth of Acanthamoeba castellanii. Proliferation of Acanthamoeba castellanii was inhibited by LFAS and LFWS at concentrations of $0.1{\times},\;0.5{\times}\;1{\times},\;and\;3{\times}.$ In addition, GSH levels were increased about 2-fold with LFAS and 1.5-fold with LFWS in cultured murine hepa1c1c7 cells. LFAS and LFWS were also shown to increase GSH levels in human Hep3B cells. These results suggest that LFAS has chemopreventive potential by inducing QR activity, inhibition of ODC activity and increasing GSH levels.

• 약학회지
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• 제47권4호
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• pp.218-223
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• 2003

Effect of taurine treatment on metabolism of glutathione (GSH) was studied in adult male ICR mice. An acute injection of taurine (250 mg/kg, ip) resulted in a significant decline of hepatic GSH level at t = 6 hr, but plasma GSH level was not altered. The activity of GSH-related enzyme in liver, such as GSH peroxidase, GSSG reductase, GSH S-transferases, ${\gamma}$-glutamylcysteine synthetase or ${\gamma}$-glutamyltranspeptidase, was not affected by taurine at t = 2.5 or 6 hr. Plasma cysteine and cystine levels were elevated rapidly following taurine treatment. Hepatic cysteine level was decreased by taurine, reaching a level approximately 70％ of control at t = 4 and 6 hr. In conclusion, the results indicate that an acute dose of taurine decreases hepatic GSH level by reducing the availability of cysteine, an essential substrate for synthesis of this tripeptide in liver. It is also suggested that taurine may decrease the cysteine uptake by competing with this S-amino acid for a non-specific amino acid transporter.