• 한국식품영양학회지
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• 제23권2호
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• pp.276-284
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• 2010

The effects of different dietary fatty acids on the hepatic glutathione S-transferase(GST-P) positive foci and glutathione related enzyme system were investigated in carcinogen treated rats. Weaning male Sprague Dawley rats were divided into three groups and fed the diets of 15% corn(CO), perilla(PO), and sardine oil(SO), respectively. Hepatocellular carcinogenesis was initiated with diethylnitrosamine(DEN) and then fed the diet containing 0.02% 2-acetylaminofluorene(2-AAF) followed by 0.05% phenobarbital for 10 weeks. The hepatic tissues were homogenized and centrifugated to prepare microsomal and cytosolic fractions. The enzyme activities of hepatic glutathione S-transferase(GST), glutathione reductase(GR), and glutathione peroxidase(GPx) were determined from cytosolic fractions. The number of GST-P hyperplastic nodules was the highest in corn oil group at 6th week, the early stage of hyperplastic nodule formation. GST activities were increased significantly by carcinogens in all dietary groups after 6th wk. GR activities followed the same trend as GST activities. GPx activities were decreased by carcinogens in all dietary groups at 10th week. In this experiment, corn oil diet may have promotive effect on hyperplastic nodule formation during the early promotional stages of chemical carcinogenesis.

• 한국식품영양과학회지
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• 제22권6호
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• pp.702-708
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• 1993

Bromobenzene투여시 GE-132의 해독기전을 추구할 목적으로 epoxide생성계와 해독계 효소 및 glutathione 관련 효소계의 활성에 GE-132가 어떤 영향을 주는가를 검토하여 다음과 같은 실험 결과를 얻었다. GE-132(100mg/kg)의 전처리로 cytochrome P-450, amino=pyrine demethylase 및 aniline hydroxylase와 해독계 효소인 epoxide hydrolase활성에는 영향을 미치지 않았으나, glutathions S-transferase활성은 증가 하였다. Bromobenzene(460mg/kg)을 주사하였을때 glutathione S-transferase의 활성이 현저히 감소되던 것이 GE-132의 투여로 대조군 수준으로 증가되었다. 조직내 glutathione의 함량변동도 bromobenzene 투여로 감소되던 것이 GE-132의 전처리로 bromobenzene단독 투여군보다 증가되었으며 ${\gamma}-glutamylcystein$ synthtase의 활성은 각 실험군에서 별다른 영향이 없는데 비해 glutathione reductase의 활성은 bromobenzene투여로 억제 되던 것이 GE-132의 전처리로 대조군 수준으로 활성을 유지하고 있었다.

• Journal of Nutrition and Health
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• 제30권7호
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• pp.803-812
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• 1997

The influences of dietary supplements of vitamin E on hepatocellular chemical carcinogenesis have been studied, Placental glutathione S-transferase(GST-P) positive foci area, antioxidant enzymes(superoxide dismutase(SOD), catalase, glutathione reductase, glutathione peroxidase, glutathione S-transferase(GST)), glucose 6-phosphatase(G6Pase) activities, and lipid peroxidation of mecrosomes(thiobarbituric acid reactive substances(TBARS) contents) were investigated. For is purpose , we used the murine chemical hepatocardinogenic procedure induced by modified Ito model, which consists of 200mg/kg body weight diethylinitrosamine (DEN) injection, 0.01% 2-acethlaminoflurene(2-AAF) feeding for 6 weeks, and partial hepatectomy on week 3. Weanling Sprague-Dawley male rats were fed pulverized Purina rat chow with 15, 000IU/kg diet vitamin E from initiation or promotion stages. We found that vitamin E supplement decreased the area of GST-P positive foci. Catalase, glutathione peroxidase, glutathione reductase. GST activities, and TBARS contents were decreased. On the other hand G6Pase activities were increased by vitamin E supplement. It seemed that vitamin E supplements helped endogenous defense systems against carcinogenesis by decreasing TBARS contents, $H_2O$$_2$ and organic peroxides. So, vitamin E seemed to protect cell from free radical damage in carcinogenesis. Anticarcinogenic effects of vitamin E were more effective at intiation that at promotion stage. These results suggest that vitamin E has suppressive effects on hepatocellular chemical carcinogenesis, probably through antioxidant effects against TBARS contents $H_2O$$_2$ and orgainc peroxides.

• 미생물학회지
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• 제33권2호
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• pp.86-91
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• 1997

Pseudomonas sp. DJ77로부터 클로닝된 glutathione S-transferase 유전자(phnC)의 염기서열을 결정하였다. 603bp의 open reading frame(ORF)이 존재하였고 개시코돈 앞에서 Shine-Dalgarno sequence를, 종결코돈 뒤에서는 terminator sequence를 발견하였다. phnC 유전자에서 만들어지는 phnC 단백질은 21,416 Da으로 SDS-polyacrylamide gel 전기영동 결과와 일치하였다. PhnC는 Bulkholderia cepacia LB400, Cycloclasticus oligotrophus RB1의 GST와 각각 53.7%, 49%의 높은 상동성을 나타냈다. 아미노산 서열의 상동성과 필수잔기들의 존재유무로 판단할 때 PhnC GST는 theta class GSTs와 진화적으로 유연관계가 높았지만 alpha, mu, pi, sigma class GSTs에서 구조적, 기능적으로 중요하다고 알려진 아미노산 잔기들이 PhnC GST에도 보존되어 있었다. 또한, phnC 유전자의 위치가 C. oligotrophus RB1, B. cepacia LB400 등의 GST 유전자 위치와 유사하다는 점에서 PhnC 효소는 난분해성 방향족 탄화수소의 분해에 관여하는 것으로 생각된다.

• Journal of Microbiology
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• 제42권1호
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• pp.42-46
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• 2004

It has recently been reported that one of the most important factors of yeast resistance to the fungicide chlorothalonil is the glutathione contents and the catalytic efficiency of glutathione S-transferase (GST) (Shin et al., 2003). GST is known to catalyze the conjugation of glutathione to a wide variety of xenobiotics, resulting in detoxification. In an attempt to elucidate the relation between chlorothalonil-detoxification and GST, the GST of Escherichia coli was expressed and purified. The drug-hypersensitive E. coli KAM3 cells harboring a plasmid for the overexpression of the GST gene can grow in the presence of chlorothalonil. The purified GST showed chlorothalonil-biotransformation activity in the presence of glutathione. Thus, chlorothalonil is detoxified by the mechanism of glutathione conjugation catalyzed by GST.

• Asian Pacific Journal of Cancer Prevention
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• 제13권6호
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• pp.2949-2953
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• 2012

The glutathione S transferase (GST) family is a major part of cellular defense mechanisms against endogenous and exogenous substances, many of which have carcinogenic potential. Alteration in the expression level or structure of the glutathione-S-transferase (GST) enzymes may lead to inadequate detoxification of potential carcinogens and consequently contribute to cancer development. A member of the glutathione-S-transferase (GST) family, GSTP1, is an attractive candidate for involvement in susceptibility to carcinogen-associated colorectal cancer. An $Ag{\rightarrow}G$ transition in exon 5 resulting in an Ile105Val amino acid substitution has been identified which alters catalytic efficiency. The present study investigated the possible impact of Ile105Val GSTP1 polymorphism on susceptibility to colorectal cancer. in Jordan We examined 90 tissue samples previously diagnosed with colorectal carcinoma, and 56 non-cancerous colon tissues. DNA was extracted from paraffin embedded tissues and the status of the GSTP1 polymorphism was determined using a polymerase chain reaction restriction fragment length polymorphism (RFLP) method. No statistically significant differences were found between colorectal cancer cases and controls for the GSTP1 Ile/Ile, Ile/Val and Val/Val genotypes. The glutathione S-transferase polymorphism was not associated with risk in colorectal cancer cases in Jordan stratified by age, sex, site, grade or tumor stage. In conclusion, the GSTP1 Ile105Val polymorphism is unlikely to affect the risk of colorectal cancer.

• 한국식품영양학회지
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• 제26권4호
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• pp.725-730
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• 2013

In this study, an ethanol extract being obtained from Allium cepa var. cepa examins the inhibitory effects on the glutathione S-transferase and the separation had been done by silica-gel column chromatography using various eluents, such as ethyl acetate, methanol, and 50% methanol. A volume of column fraction was 50ml and evaporation has been performde by the rotary evaporator under reduced pressure. Each fraction is being examined by thin layer chromatography and the UV spectrum at 365 nm was used to investigate separation patterns of spots on thin layer chromatography. When the eluent was changed, the spot patterns showed another different pattern on thin layer chromatography, so on. Fractions showing similar pattern are combined and eventually, three fractions are obtained. Each fraction is testified to examine the inhibition effects on glutathione S-transferase. All of these showed inhibition effects on glutathione S-transferase. The GC-MS shows that each fraction contains more than 2 compounds.

• 분석과학
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• 제23권2호
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• pp.172-178
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• 2010

Glutathione S-transferase는 식물의 해독작용에 중추적인 역할을 하는 화학 효소이다. 본 연구에서는 제초제 검출 키트 개발에 응용을 위하여 식물 해독작용에 중추적인 역할을 하는 glutathione Stransferase의 고정화 방법을 연구하였다. Chloroacetanilide계 제초제에 높은 효소 활성을 보이는 벼 유래 OsGSTF3에 공유결합을 통한 polystyrene-alkylamine 비드와 리간드결합을 통한 agarose-aminoalkyl 비드,포괄법을 통한 Na-alginate 비드를 이용하여 고정화를 실시하였다. 정제된 OsGSTF3 10 mg을 사용하여 고정화 하였을 때 0.62 mg/g 비드로 polystyrene-alkylamine에 가장 효율적으로 고정화 되었다. 고정화 된 OsGSTF3의 효소 활성은 야생형의 30%를 나타내었으며, 재사용에 의한 효소활성 측정시 3회 까지 처음 활성의 80% 이상을 유지하였다.

• 생약학회지
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• 제34권2호통권133호
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• pp.161-165
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• 2003

Ethanol extract from Thesium chinense Tunczaninov (TCTE) was tested for breast cancer chemopreventive activity by measuring 7,12-dimethylbenz[a]anthracene (DMBA) - induced cytochrome P450 1A1 activity, induction of quinone reductase and glutathione S-transferase, and glutathione level. TCTE significantly inhibited cytochrome P45O 1A1 activity at the concentration of 90 and 150 mg/ml. TCTE induced quinone reductase activity in a dose-dependent manner in a concentration range of 3-150 mg/ml. In addition glutathione S-transferase activity and glutathione level were increased with TCTE in cultured murine hepatoma Hepa1c1c7 cells. These results suggest that TCTE has breast cancer chemopreventive potential by inhibiting cytochrome P45O 1A1 activity, inducing quinone reductase and glutathione S-transferase activities, and increasing GSH level.

• 농약과학회지
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• 제8권1호
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• pp.16-21
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• 2004

본 연구는 6종 나방류(멸강나방, 배추좀나방, 목화바둑명나방, 파밤나방, 담배나방, 담배거세미나방) 대한 유충영기별 thiodicarb의 살충활성을 조사하였으며, 살충효과 구명을 위하여 효소활성(esterase, acetylcholinesterase, glutathione S-transferase)등을 검토하였다. 이 약제는 6종의 나방류 어린유충에 대해서 높은 살충효과를 나타내었으나, 노숙유충에 대한 살충효과는 상대적으로 낮았고, 발현속도는 느렸다. 담배거세미나방을 대상으로 한 효소활성저해 실험에서 acetylcholinesterase와 glutathione S-transferase 활성을 저해하였으나, esterase 활성을 저해하지는 않았다.