• BMB Reports
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• 제41권6호
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• pp.444-447
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• 2008

Trypanothione reductase is an important target enzyme for structure-based drug design against Leishmania. We used homology modeling to construct a three-dimensional structure of the trypanothione reductase (TR) of Leishmania infantum. The structure shows acceptable Ramachandran statistics and a remarkably different active site from glutathione reductase(GR). Thus, a specific inhibitor against TR can be designed without interfering with host (human) GR activity.

• Biomolecules & Therapeutics
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• 제13권4호
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• pp.232-239
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• 2005

An aqueous extract of oriental herbal composition named Onchengyeum and curcumin, an antioxidant isolated from turmeric (Curcuma Zonga L.) reduced hepatotoxicity induced by carbon tetrachloride ($CCI_4$). Improved liver function was observed by measuring the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), blood urea nitrogen (BUN), creatinine (CRE), total cholesterol (T-CHO), triglyceride (TG), low density lipoprotein cholesterol (LDL-CHO), high density lipoprotein cholesterol (HDL-CHO), total protein (TP), albumin (ALB) and total bilirubin (BIL) in serum. Hepatic parameters monitored were levels of cholesterol (CHO), triglyceride (TG), and malondialdehyde (MDA) and activities of cytochrome P450 (CYP), NADPH-CYP reductase, superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), glutathione S-transferase (GST), glutathione reductase (GR), and glutathione peroxidase (GPx). The histopathological examination showed that the treatment of Onchengyeum and curcumin relieved the ballooning degeneration of hepatocytes which had been generated by $CCI_4$. The results suggested that hepatoprotective effects of Onchengyeum and curcumin possibly are due to their promising antioxidative activity.

• Journal of Microbiology and Biotechnology
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• 제11권6호
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• pp.1071-1076
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• 2001

Chemopreventive activities of polysaccharides from soybeans fermented with either Phellinus igniarius or Agrocybe cylindracea were investigated by measuring the induction of quinone reductase (QR), glutathione S-transferase (GST) activities, and glutathione (GSH) levels in the cell culture along with inhibition of polyamine biosynthesis. The polysaccharides from soybeans fermented with P. igniarius strongly (p<0.005) induced QR activity at all concentrations tested. The extract not only induced GST activity in a dose-dependent manner in the concentration range of 0.1-1.0 mg, but significantly induced GSH revels in cultured Hepa 1c1c7 cells with a maximal 1.4-fold increase at 0.1 mg. The polysaccharides from soybeans fermented with A. cylindracea were effective in inhibiting polyamine metabolism. These results suggest that polysaccharides from soybeans fermented with P. igniarius or A. cylindracea have cancer chemopreventive activities in in vitro models and, therefore, could be considered as potential agents for cancer chemoprevention.

• 약학회지
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• 제40권6호
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• pp.720-726
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• 1996

The neurotoxicity induced by L-glutamate in primary cultures of rat cortical cells could be attenuated by diterpene constituents of Ginkgo biloba leaves, ginkgolides A, B and C. At the concentration of 100 nM, ginkgolides up-regulated the activity of glutathione reductase in primary cultures of rat cortical cells exposed to 100 ${\mu}$M glutamate. Furthermore, ginkgolides increased the content of reduced glutathione in glutamate-treated cortical cells. However, ginkgolides showed little effect in reducing superoxide dismutase activity. Ginkgolides did, however, markedly block the production of malondialdehyde, a byproduct of lipid peroxidation in glutamate-treated rat cortical cells.

• Biomolecules & Therapeutics
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• 제14권4호
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• pp.207-215
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• 2006

Sachungwhan reduced hepatotoxicity induced by carbon tetrachloride($CCl_4$). Improved liver function was observed by measuring the activities of aspartate aminotransferase(AST), alanine aminotransferase(ALT), alkaline phosphatase(ALP), blood urea nitrogen(BUN), creatinine(CRE), total cholesterol(TCHO), triglyceride(TG), low density lipoprotein cholesterol(LDL-CHO), high density lipoprotein cholesterol(HDL-CHO), total protein(TP), albumin(ALB) and total bilirubin(BIL) in serum. Hepatic parameters monitored were levels of cholesterol(CHO), triglyceride(TG), malondialdehyde(MDA), content of cytochrome P450(CYP), level of glutathione(GSH), and activities of NADPH-CYP reductase, superoxide dismutase(SOD), catalase(CAT), glutathione S-transferase(GST), glutathione reductase(GR), glutathione peroxidase(GPx). The histopathological examination showed that the treatment of Sachungwhan relieved the ballooning degeneration of hepatocytes which had been generated by $CCl_4$. The results suggested that hepatoprotective effects of Sachungwhan possibly are due to their promising antioxidative activity.

• Korean Journal of Acupuncture
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• 제18권1호
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• pp.1-9
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• 2001

애엽으로 약침액을 조제하여 암예방 효과를 살펴 본 결과 다음과 같은 결론을 얻었다. 애엽 약침액으로 10일간 전투여한 후 Ehrlich ascites tumor cell을 이식하여 복수암이 유발된 생쥐의 EATC 성장을 살펴 본 결과 약침액을 투여한 생쥐의 EATC의 성장이 크게 억제되었으며, 복수암이 유발된 생쥐의 비장 무게가 대조군에 비해 증가하였다. 또한 장기간의 관찰에 의해서도 복수암 세포의 성장 저해에 의해 생쥐의 체중변화율은 대조군에 비해 크게 억제되었으며 수명 연장 효과가 나타났다. 이와같은 생체에서의 암예방 효과를 in vitro 상에서 그 기전을 살펴본 결과 애엽 약침액은 phase II detoxification 효소인 QR의 생성을 유도하고 GSH 함량을 증가시켜서 암예방 효과를 나타내었다.

• Plant Biotechnology Reports
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• 제5권4호
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• pp.353-365
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• 2011

The present study investigates the possible regulatory role of exogenous nitric oxide (NO) in antioxidant defense and methylglyoxal (MG) detoxification systems of wheat seedlings exposed to salt stress (150 and 300 mM NaCl, 4 days). Seedlings were pre-treated for 24 h with 1 mM sodium nitroprusside, a NO donor, and then subjected to salt stress. The ascorbate (AsA) content decreased significantly with increased salt stress. The amount of reduced glutathione (GSH) and glutathione disulfide (GSSG) and the GSH/GSSG ratio increased with an increase in the level of salt stress. The glutathione S-transferase (GST) activity increased significantly with severe salt stress (300 mM). The ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), catalase (CAT) and glutathione peroxidase (GPX) activities did not show significant changes in response to salt stress. The glutathione reductase (GR), glyoxalase I (Gly I), and glyoxalase II (Gly II) activities decreased upon the imposition of salt stress, especially at 300 mM NaCl, with a concomitant increase in the $H_2O_2$ and lipid peroxidation levels. Exogenous NO pretreatment of the seedlings had little influence on the nonenzymatic and enzymatic components compared to the seedlings of the untreated control. Further investigation revealed that NO pre-treatment had a synergistic effect; that is, the pre-treatment increased the AsA and GSH content and the GSH/GSSG ratio, as well as the activities of MDHAR, DHAR, GR, GST, GPX, Gly I, and Gly II in most of the seedlings subjected to salt stress. These results suggest that the exogenous application of NO rendered the plants more tolerant to salinity-induced oxidative damage by enhancing their antioxidant defense and MG detoxification systems.

• 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.

• 약학회지
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• 제42권1호
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• pp.108-113
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• 1998

G009, a polysaccharide isolated from the mycelia of Ganoderma lucidum IYO09, showed a hepatoprotective activity against $CCl_4$ induced cytotoxicity in primary cu ltured rat hepatocytes. Incubation of $CCl_4$-intoxicated hepatocytes with G009 significantly reduced the levels of glutamic pyruvic transaminase and sorbitol dehydrogenase released from hepatocytes in the medium. G009 showed antioxidative effect by elevating the activities of glutathione reductase and superoxide dismutase, and the content of glutathione in $CCl_4$-intoxidcated primary cultured rat hepatocytes. Furthermore, G009 significantly elevated glutathione-S-transferase activity in $CCl_4$-intoxicated primary cultured rat hepatocytes. G009 also reduced the production of malondialdehyde, a byproduct of lipid peroxidation. From these results, it could be concluded that G009 exerted hepatoprotective activity against $CCl_4$-induced cytotoxicity through antioxidation.

• Applied Biological Chemistry
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• 제43권1호
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• pp.46-51
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• 2000

망초(Conyza bonariensis)에서 제초제 paraquat 저항성을 구명하기 위해 paraquat가 생성하는 superoxide 라디칼과 과산화수소 등의 유해 산소 물질을 제거하는 데에 관련된 효소의 활성을 저항성 종과 감수성 종의 망초에서 측정하였다. 경작지 부근에 자라는 망초는 비경작지에 자라는 망초에 비해 paraquat 저항성이 강하였다. 국내에서 paraquat를 자주 살포하는 지역에서 저항성 종의 망초가 출현하고 있음을 처음으로 보고한다. 저항성 종의 superoxide dismutase의 활성, ascorbate peroxidase의 활성, 그리고 glutathione reductase의 활성은 감수성의 그것에 비해 각각 약 20%, 44%, 그리고 64% 높게 나타났다. 이러한 결과로부터 paraquat에 대한 망초의 저항성은 superoxide dismutase, ascorbate peroxidase, 그리고 glutathione reductase 등으로 구성된 효소의 유해 산소 물질을 제거하는 효율성에 부분적으로 달려 있을 수 있다고 사료된다.