• 대한예방의학회:학술대회논문집
• /
• 대한예방의학회 1998년도 제50차 추계 학술대회 연제집
• /
• pp.291-292
• /
• 1998

• 약학회지
• /
• 제39권5호
• /
• pp.528-534
• /
• 1995

This investigation was aimed at the study of the antidiabetic activity and effect on hepatic glutathione metabolism of polysaccharide from Trichosanthes kirilowii in hyperglycemic rats with aboxan (175 mg/Kg, i.p.). As the results, the polysaccharide inhibited the increase of blood glucose, triglyceride level and lactate dehydrogenase activity, but cholesterol not changed. And it increased protein bound-SH, nonprotein bound-SH, glutathione level and inhibited the decrease of glutathione S-transferase.

• BMB Reports
• /
• 제31권4호
• /
• pp.399-404
• /
• 1998

In order to gain further insight on the relationship between structure and function of glutathione S-transferase (GST), the six active-site mutants, R13T, K44T, Q51A, Q64A, S65A, and D98A, of human GST P1-1 were expressed in Escherichia coli and purified to electrophoretic homogeneity by affinity chromatography on immobilized GSH. The active-site mutants showed marked differences in substrate specificity. The substitution of Gln51 with threonine resulted in a drastic decrease in the specific activities to <10% of the wild-type value. The substitution of Arg13 with threonine resulted in more decreased specific activity toward cumene hydroperoxide and in the $I_{50}$ values of S-(2,4-dinitrophenyl) glutathione and benanstatin A. These results suggest that the substitution of Arg13 with threonine changes the conformation of the active site to increase the affinity for the product or electrophilic substrate. Lys44 seems to be in the vicinity of the H-site of hGST P1-1 or may contribute to some extents to the electrophile binding.

• 농약과학회지
• /
• 제2권1호
• /
• pp.97-103
• /
• 1998

제초제 alachlor와 metolachlor가 처리된 수수의 생장에 대한 약해경감제 fluxofenim의 약해 경감효과와 경감기작의 하나로 추정되는 GST 활성에 대하여 조사하였다. 제초제 metolachlor와 alachlor는 수수(품종;G522DR)의 유묘생장을 크게 억제하였는데, 지상부 및 뿌리에 대한 50% 생장억제 농도가 각각 30.8, 28.8 ${\mu}M$과 4.48, 6.23 ${\mu}M$로 두 약제 모두 수수의 지상부에 대한 억제보다 뿌리에 대한 억제가 컸다. Fluxofenim을 종자에 처리하여 파종하고 metolachlor또는 alachlor을 처리하면 수수의 유묘생장이 회복되어 fluxofenim처리에 의한 약해경감 효과가 크게 나타났다. 약해경감제 fluxofenim을 처리한 것과 처리하지 않은 수수 유묘로부터 추출한 GST의 활성을 비교한 결과, fluxofenim을 처리한 수수의 유묘로부터 추출한 GST의 활성이 CDNB를 기질로 사용하였을때 70% 증가되었고, [$^{14}C$]-metolachlor을 기질로 사용하였을 때에도 82% 증가되었다. 따라서 약해경감제 fluxofenim을 처리한 수수와 처리하지 않은 수수의 metolachlor또는 alachlor에 대한 선택성의 차이는 fluxofenim 처리로 증가된 GST에 의한 metolachlor-glutathione 또는 alachlor-glutathione conjugation되기 때문인 것으로 생각된다.

• 생명과학회지
• /
• 제12권5호
• /
• pp.549-554
• /
• 2002

포공영약침액의 암억제 효과를 살펴보기 위하여 quinone reductase (QR) 생성유도를 생쥐의 간암세포인 Hepa Iclc7를 이용하여 측정한 결과, 포공영약침액을 처리한 Hepa Iclc7에서 QR생성이 유도되었다. 또한 포공영약침액은 phase II detoxification 효소인 glutathione S-transfer-ase (CST) 활성을 증가시키고 glutathione 생성도 증가시켰다 QR과 CST는 간세포에서 주로 생성되는 phase II효소로 발암물질에 의해 일어나는 돌연변이와 종양화 효과를 막아주고 발암물질을 무독화 시키는 것으로 알려져 있다. 따라서 본 실험에서 포공영약침액은 QR 효소 생성 유도, glutathione 함량 증가 및 CST 효소활성 증대등 phase II detoxification의 기작을 통한 발암과정의 blocking agent로서 효과가 있음을 알 수 있었다.

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

• Bulletin of the Korean Chemical Society
• /
• 제28권5호
• /
• pp.772-776
• /
• 2007

In order to study the role of residue in the active site of glutathione S-transferase (GST), Arg13 residue in human GST P1-1 was replaced with alanine, lysine and leucine by site-directed mutagenesis to obtain mutants R13A, R13K and R13L. These three mutant enzymes were expressed in Escherichia coli and purified to electrophoretic homogeneity by affinity chromatography on immobilized GSH. Mutation of Arg13 into Ala caused a substantial reduction of the specific activity by 10-fold. Km GSH, Km DCNB and Km EPNP values of R13A were approximately 2-3 fold larger than those of the wild type. Mutation of Arg13 into Ala also significantly affected I50 values of S-methyl-GSH that compete with GSH and ethacrynic acid, an electrophilic substrate-like compound. These results appeared that the substitution of Arg13 with Ala resulted in significant structural change of the active site. Mutation of Arg13 into Leu reduced the catalytic activity by approximately 2-fold, whereas substitution by Lys scarcely affected the activity, indicating the significance of a positively charged residue at position 13. Therefore, arginine 13 participates in catalytic activity as mainly involved in the construction of the proper electrostatic field and conformation of the active site in human GST P1-1.

• 한국식품영양학회지
• /
• 제28권5호
• /
• pp.866-870
• /
• 2015

In this study, coffee waste was extracted with different solvents such as ethyl acetate, methylene chloride and methanol to investigate the total polyphenol contents, electron donating ability and the inhibitory effect on glutathione S-transferase. The total polyphenol contents were $3,060.61{\pm}357.12{\mu}g\;GAE/mL$ in ethyl acetate, $909.09{\pm}35.71{\mu}g\;GAE/mL$ in methylene chloride, and $1,602.27{\pm}30.36{\mu}g\;GAE/mL$ in methanol. The total polyphenol contents showed a significant difference (p<0.05) between the solvents. The electron donating ability was $80.20{\pm}1.45%$ for ethyl acetate, $81.94{\pm}0.45%$ for methylene chloride, and $85.14{\pm}1.53%$ for methanol. The electron donating abilities were significantly different (p<0.05) between the solvents. The inhibitory effect of the various extracts on glutathione S-transferase (% inhibition) was $92.12{\pm}0.56%$, $88.48{\pm}0245%$ with methylene chloride extract, and $90.85{\pm}0.14%$ with methanol extract. These too were significant different (p<0.05) between the solvents. The two portions of coffee waste extracts obtained from ethyl acetate and methanol showed meaningful results on the total polyphenol contents, and the inhibition effects on glutathione S-transferase. Therefore, they can be utilized to develop health care foods and can be applied as antioxidants for cosmeceuticals.

• BMB Reports
• /
• 제29권2호
• /
• pp.111-115
• /
• 1996

A novel glutathione S-transferase from Pseudomonas sp. DJ77 was expressed in E. coli and purified by glutathione-affinity chromatography. The enzyme was composed of two identical subunits. The molecular size of the enzyme was 42 kDa by sephadex G-150 gel permeation chromatography and Mr of each subunit was 23 kDa by sodium dodecylsulfate-polyacrylamide gel electrophoresis. pI value of the enzyme was approximately 5.8 by isoelectric focusing. This enzyme showed the highest activity toward 1-chloro-2,4-dinitrobenzene as the electrophilic substrate. The relative activities toward p-nitrobenzyl chloride and 1,2-dichloro-4-nitrobenzene were 3.8% and 1.3% of the activity toward 1-chloro-2,4-dinitrobenzene, respectively. $K_m$ and $V_{max}$ values for 1-chloro-2,4-dinitrobenzene calculated by Lineweaver-Burk plot were 0.76 mM and $14.81\;{\mu}mol/min/mg$, respectively, and those for glutathione were 6.23 mM and $64.93\;{\mu}mol/min/mg$, respectively. The enzyme showed highest glutathione S-transferase activity at pH 8.0 and was stable between pH 6.0 and 9.0. The enzyme retained its activity up to $35^{\circ}C$ for 90 min but was unstable above $45^{\circ}C$.

• 한국콘텐츠학회논문지
• /
• 제17권10호
• /
• pp.289-299
• /
• 2017

아시아인종에서 만성골수성백혈병 (Chronic myeloid leukemia; CML)과 Glutathione S-transferase(GST) 유전자 다형성과 관련된 감수성을 검증하기 위해, 2017년 7월까지 발표된 9편의 논문들을 메타분석에 인용하였다. GST 유전자 다형성의 아형 중 M1 (GSTM1)과 T1 (GSTT1)의 유전자의 null, present 유형을 개별적으로 분석하였다. CML환자와 GST 유전자 다형성 사이에 연관성이 발견되었다.(GSTM1; OR=1.306, 95% CI=1.091-1.563, p=0.004, GSTT1; OR=1.987, 95% CI=1.438-2.746, p=0.000). 또한, CML 환자와 GSTM1-GSTT1 유전자 다형성 조합 null 유형의 연관성이 있었다(OR=4.191, 95% CI=2.833-6.201, p=0.000). 이와 같이, 아시아인종에서 GSTM1 유전자 다형성, GSTT1 유전자 다형성, GSTM1-GSTT1 유전자 다형성 조합은 CML 환자의 위험인자가 될 수 있다.