• Applied Biological Chemistry
• /
• v.51 no.3
• /
• pp.228-232
• /
• 2008

In the present study, we investigated the glutathione S-transferase (GST) induction of medicinal plants using a cultured PC12 cells. The methanol extracts of Dendrobium nobile Lindley, Schizonepeta tenuifolia Briquet, Glycyrrhiza uralensis Fischer, Paenoia lactiflora Pall were tested. As the result, exposure of PC12 cells to G. uralensis resulted in the significant induction of GST. On the continuous experiment, G. uralensis was extracted with methanol, ethanol, and acetone. Among these extracts, methanol extracts showed the highest GST induction. The methanol extracts were further fractionated with hexane, diethyl ether, ethyl acetate, and water layer according to the degree of polarity. The diethyl ether layer showed the highest exhibited GST induction on PC12 cells. Based on these results suggest that the extracts of G. uralensis can be applicable for the development of a new antioxidant agent.

• Journal of Nutrition and Health
• /
• v.25 no.1
• /
• pp.3-11
• /
• 1992

This paper examines the effects of dietary fats on the fatty acid composition and market enzyme activites during liver damage in 2-acetylaminofluorene treated rats. Weaning Sprague-Dawley male rats were fed the diet of beef tallow(BT source of sturated fatty acid) corn oil(CO source of n-6 fatty acid) and perilla oil(PO source of n-3 fatty acid) at the level of 15% fat. Ten days after feeding 2-acetylaminofluorene(2-AAF) was injected intraperitoneally twice every week at the level of 50mg/kg body weight for 7 weeks. Liver microsomal and cytosolic fractions were collected to determine the microsomal fatty acid composition lipid peroxide(malondialdehyde MDA) contents glucose 6-phosphatase(G6 Pase) activity cytochrome(Cyt) P-450 contents and cytosolic glutathione S-transferase(G6 Pase) activity cytochrome(Cyt) P-450 contents and cytosolic glutathione S-transferase(GST) activity. The fatty acid composition in microsomal fraction was reflected by different dietary fats. By 2-AAF treatment linoleic acids were increased regardless of the diet MDA contents were higher in CO group than it was in BT group. However 2-AAF treatment decreased MDA contents in all dietary groups. G6Pase activity of BT group was higher than those of the other gropus. CO group had the highest Cyt P-450 contents and 2-AAF treatment lowered Cyt P-450 contents only in CO gropu GST activites were higher in CO than in BT group whereas the enzyme activites were increased by 20AAF treatment in all dietary groups. These results suggest that dietary fats and 2-AAF treatment in all dietary groups,. These results suggest that dietary fats and 2-AAF treatment affect microsomal fatty acid composition The enzyme activities concerned with liver damage were influenced differently by dietary fats and 2-AFF treatment Although PO diet contains much more polyunsaturated fatty acids than CO diet PO diet doesn't cause more oxidant stress compared with CO diet in these data.

• Journal of Environmental Health Sciences
• /
• v.29 no.2
• /
• pp.80-86
• /
• 2003

To evaluate the effect of cyclohexane(CH) treatment on the serum levels of glutathion S-transferase(GST) activity in liver damaged animals, damaged liver was induced with pretreatment of 50% $CCl_4$ dissolved in olive oil (0.1 m1/100g body weight) intraperitoneally 17 times every other day. To $CCl_4$-treated rats, CH (1.56 g/kg body weight, i.p) was injected once and then the animals were sacrificed at 4 hours after injection of CH. The $CCl_4$-treated animals were identified as severe liver damage on the basis of liver functional findings, 1,e, increased serum levels of alanine aminotransferase(ALT), alkaline phosphate(ALP) and xanthine oxidase(XO) activities. On the other hand, $CCl_4$-treated animals injected with CH once($CCl_4$-pretreated animals) showed more decreased serum levels of ALT and XO, and more increased those of ALP rather than $CCl_4$-treated animals. In case of comparing the GST with ALT activity in liver, both $CCl_4$-treated and pretreated animals showed similar changing pattern of enzyme actvity. Especially $CCl_4$-pretreated animals showed significantly increased serum level of GST actvity compared with the $CCl_4$-treated those, whereas those of ALT showed reversed tendency. In aspects of GST enzyme kinetics, $CCl_4$-pretreated animals showed higher Vmax of liver GST enzyme than $CCl_4$-treated animals. In conclusion, injection of CH to the liver damaged rats led to enhanced liver damage and more increased activity of serum GST which may be chiefly caused by the enzyme induction.

• Toxicological Research
• /
• v.13 no.4
• /
• pp.409-415
• /
• 1997

The influences of dietary supplement of citron tea on the hepatocellular chemical carcinogenesis have been studied by examining placental glutathione S-transferase(GST-P) positive foci area in a liver tissue, contents of total cytochrome P450, thiobarbituric acid reactive substances(TBARS) and glucose 6-phosphatase(G6Pase) in hepatic microsome and glutathione S-transferase(GST) activity. Weaning Sprague-Dawley male rats were fed AIN76 diet with or without citron tea supplement. Rats of CTR and CTR+ groups were fed diet without citron tea supplement while CDI and CDI+ groups were fed diet with citron tea supplement for the entire experimental period(13 weeks). Rats of CDP and CDP+ groups were fed diet without citron tea supplement for the first 7 weeks and swiched to citron tea containing diet for the last 6 weeks of experimental period. CTR+, CDI+ and CDP+ groups were carcinogen treated group. Diethylnitrosamine(DEN) was used as a carcinogen initiator and injected to the rats of carcinogen treated groups as a single dose of 200 mg/kg body weight intraperitoneally after 4 weeks of feeding. 2-Acethylaminofiuorene(AAF) was used as a carcinogen promoter and supplied in the diets of carcinogen treated rats as 0.02% content for the last 6 weeks starting from 2 weeks after DEN injection. Rats were sacrificed after 13 weeks of feeding. Liver/body weight ratio and GST activities were increased by carcinogen treatment. However, they were not changed by citron tea supplement. Total cytochrome P450 contents were not changed by carcinogen treatment or citron tea supplement. TBARS contents of carcinogen treated rats showed tendency to decrease by citron tea supplement. G6Pase activity decreased by carcinogen treatment and citron tea supplement. The area of GST-P positive foci detected in carcinogen treated rats were decreased by citron tea supplement and not affected by the timing and the duration of citron tea supplement. These results suggest that citron tea has suppressive effects on hepatocellular chemical carcinogenesis probably through antioxidant compounds by decreasing TBARS contents.

• Korean Journal of Medicinal Crop Science
• /
• v.16 no.6
• /
• pp.427-433
• /
• 2008

This study was performed to investigate antioxidant activities and glutathione S-transferase (GST) activity according to parts of the Acer mono and A. okamotoanum. Most extracts showed high scavenging activities on DPPH. Especially, the bark of A. okamotoanum showed higher activity as 98.4% than the control, BHA as 96.5%. A. mono and A. okamotoanum showed high ability on nitrite scavenging, but decreasing tendency according to decreasing of pH. On SOD-like test, the wood of A. okamotoanum showed highest activity as 35.4% at 1.0mg/ml concentration. Also, the extracts obtained high activity on GST test. Therefore, the water extracts from the bark of A. mono and A. okamotoanum have relatively good antioxidant activity and GST activity. Especially, the bark of A. okamotoanum showed the highest activity on all of extracts, could be the use of functional foods and biomaterials.

• Journal of Life Science
• /
• v.13 no.2
• /
• pp.230-235
• /
• 2003

To investigate hepatoprotective activities of the root extract of Rosa davurica, the activities of hepatic enzymes, aminopyrine N-demethylase, aniline hydroxylase, glutathione S-transferase and epoxide hydrolase in rats intoxicated with bromobenzene were studied. Pretreatment with the methanol extract from the roots of Rosa davurica did not show any significant effects on the increases of the activities of aminopyrine N-demethylase and aniline hydroxylase, enzymes forming toxic epoxide by bromobenzene. There was no change in glutathione S-transferase activity by Rosa davurica. However, the activity of epoxide hydrolase, and epoxide-removing enzyme, was increased 33% by the administration of 500 mg/kg of the methanol extract. From the results, the protection of Rosa davurica against bromobenzene-induced hepatotoxicity is thought to be via enhancing the activity of epoxide hydrolase, an enzyme removing toxic epoxide rather than through epoxide-producing system.

• Korean journal of applied entomology
• /
• v.35 no.3
• /
• pp.254-259
• /
• 1996

The biochemical factors responsible for parathion resistance in a ethyl fenitrothion-selected Yumenoshima I11 (EF-30) strain of the housefly were examined. Great difference (167-fold) in the Iso was observed between the resistant EF-30 (R) and susceptible SRS (S) strains in vitro, suggesting that altered acetylcholinesterase (AChE) in the housefly strain was an important factor in the resistance. The in vitro degradative activity of parathion and paraoxon in both strains was associated with the microsomal and soluble fractions and required NADPH and reduced glutahione (GSH), respectively. The R strain possessed higher activity for GSH S-transferase than the S strain, and this enzyme appears to be important in the resistance mechanism. The R strain was highly resistant to parathion (101,487-fold), but substitution of the methoxy group for ethoxy group decreased the resistance level (25,914-fold) and parathion could be a substrate of GSH S-transferase. It is concluded that the combination of some factors (altered AChE, and enhanced activity of cytochrome P450 dependent monooxygenase and GSH S-transferase) could be sufficient to account for the extremely high level of resistance to parathion and parathion-methyl, although a possible involvement of other factor(s) can not be excluded.

• Korean Journal of Environmental Agriculture
• /
• v.16 no.1
• /
• pp.37-43
• /
• 1997

Tolerance mechanism to simazine (6-chloro-N,N'-diethyl-1,3,5-triazine-2,4-diamine) in Coix lacryma-jobi was investigated with respect to herbicide detoxification via glutathione conjugation. Simazine was initially absorbed by seedlings of C. lacryma-jobi and corn, but after 12 hours of treatment, no significant difference in simazine absorption was found in both species. Simazine absorbed was rapidly metabolized to glutathione-simazine conjugate. One to six hours after treatment, metabolism was approximately 2-fold faster in C. lacryma-jobi than in corn. Glutathione content was found 1.5- and 2.3-fold higher in coleoptile and root of C. lacryma-jobi, respectively, compared with corn. In both species, the highest concentration of glutathione was found in coleoptile tissue. Glutathione S-transferase that exhibits activity with 1-chloro-2,4-dinitrobenzene was not significantly different between two species. However, glutathione S-transferase activity with simazine was approximately 2-fold greater in C. lacryma-jobi than in corn. The glutathione S-transferase activity was 20 to 30% greater in shoot of either species than in root. Fast protein liquid chromatography-anion exchange column was used to separate glutathione S-transferase isozymes in coleoptiles of C. lacryma-jobi and corn. A peak of glutathione S-transferase activity with 1-chloro-2,4-dinitrobenzene and two peaks of glutathione S-transferase activity with simazine from C. lacryma-jobi were coeluted with those from corn, but showed greater activity than in the case of corn. Another glutathione S-transferase isozyme that exhibits activity with simazine was detected in the elution of C. lacryma-jobi extract, but not in corn. Electron transport in chloroplast thylakoids isolated from leaves of both species was equally sensitive to simazine applied at 1 to 100 nM. These results indicate that the simazine tolerance in C. lacryma-jobi is due to its capacity to detoxify the herbicide via glutathione conjugation, which is positively correlated with the level of glutathione content and glutathione S-transferase activity.

• The Journal of Korean Medicine
• /
• v.25 no.4
• /
• pp.36-42
• /
• 2004

Objective : Glutathione S-transferase polymorphism (GST) were examined in 120 cases with ischemic cerebrovascular disease (ICVD) to test the hyperthesis that GST polymorphisms confer a risk to an individual to develop ICVD. Tobacco smoking is a major cause of both cancer and vascular disease. Methods : therefore We were stratified the subjects with ICVD for smoking status, and then examined whether polymorphisms in this detoxification enzyme gene, GST, influence risk of ICVD Results : Neither GSTM1 nor GSTT1 genotypes in the ICVD group was significantly different from the control group (n=207), even in smokers. We attempted the combined analyses for GSTM1 and GSTT1 genotypes in ICVD for smoking status. No significant association observed between the combined genotypes and ICVD Conclusion : Our observation do not confirm the effect of the GSTM1 and GSTT1 genotypes as a risk factor for ICVD, even in smokers.

• Bulletin of the Korean Chemical Society
• /
• v.24 no.8
• /
• pp.1188-1192
• /
• 2003

In order to study the role of residue in the active site of glutathione S-transferase (GST), Tyr 108 residue in human GST P1-1 was replaced with alanine, phenylalanine and tryptophan by site-directed mutagenesis to obtain mutants Y108A, Y108F and Y108W. These three mutant enzymes were expressed in Escherichia coli and purified to electrophoretic homogeneity by affinity chromatography on immobilized GSH. The substitutions of Tyr108 significantly affected $K_m^{CDNB}$ and $K_m^{ETA}$, whereas scarcely affected $K_m^{GSH}$. The substitutions of Tyr108 also significantly affected $I_{50}$ of ETA, an electrophilic substrate-like compound. The effect of these substitutions on kinetic parameters and the response to inhibition suggests that tyrosine 108 in hGST P1-1 contributes to the binding of the electrophilic substrate and a major determinant in the binding of CDNB is the aromatic ring of Tyr108, not its hydroxyl group.