• Journal of Nutrition and Health
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• v.23 no.6
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• pp.418-426
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• 1990

This study examines the effects of choline deficiency and 2-acetylaminofluorene(2-AAF) on the lipid peroxide values, glucose 6-phosphatase(G6Pase) and glutathione S-transferase (GST) activities in rats fed different dietary fats. Weanling Sprague Dawley male rats fed the diets containing 15% beef tallow or 15% corn oil with vitamin fortification mixture or choline free vitamin mixture for 10 weeks. At 3th and 5th week, 2-AAF was injected twice each week intraperitoneally. Total 2-AAF injection was four times. 2-AAF and choline deficiency increased lipid peroxidation in corn oil groups, so the role of 2-AAF and choline deficiency in lipid peroxidation was more important in corn oil groups than beef tallow groups. G6Pase activities tended to be decreased by 2-AAF in choline deficient groups, and in corn oil groups, the enzyme activities were decreased significantly in all subgroups compaired to beef tallow groups. GST activities were increased by 2-AAF in beef tallow groups and choline deficiency in corn oil groups, and might defence against carcinogen metabolism and lipid peroxidation.

• Biomedical Science Letters
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• v.7 no.4
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• pp.191-196
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• 2001

To evaluate an effect of cyclohexanone (CHO) treatment on the serum levels of glutathione S-transferase (GST) activity in acute liver damaged animals, acute liver damage was induced in rats with pretreatment of 50% $CCl_4$ in olive oil (0.1 ml/100 g body wt) intraperitoneally 14 times every other day. To liver damaged rats, CHO (1.56 g/kg body wt, i. p.) was injected once and then rats were sacrificed at 4 hours after injection of CHO. Increasing rate of GST activity to the control in serum was higher in CHO-treated rats pretreated with CCL$_4$ than the $CCl_4$-pretreated those. All the more, the injection of CHO to the liver damaged rats led to more enhanced liver damage on the basis of liver functional findings, i. e., serum levels of alanine aminotransferase (ALT) activity, liver weight per body weight, and malondialdehyde content. The changing pattern of serum ALT activity was similar with that of GST activity, whereas that of liver in both enzymes differed more or less from each other; the liver GST activity in CHO-treated rats pretreated with $CCl_4$ being more increased tendency than that of $CCl_4$-pretreated rats. Concomitantly the injection of CHO showed a increasing tendency of liver GST activity compared with the control. Furthermore, CHO injection to the liver damaged rats showed somewhat higher Vmax in the kinetics of liver GST enzymes. In conclusion, injection of CHO to the liver damaged animals led to more increased activity of serum GST, and it may be chiefly caused by the alteration of membrane permeability.

• The Korean Journal of Food And Nutrition
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• v.28 no.3
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• pp.458-464
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• 2015

In this study, the total polyphenol content, electron donating ability (EDA) and inhibitory activity of glutathione S-transferase (GST) of freeze-dried Citrus unshiu extracts were examined. The Citrus unshiu extracts was obtained from four solvents such as ethyl acetate, acetone, methyl chloride and methanol, to evaluate its functional properties. Total polyphenol contents were measured in the two different extracts, and the extracts were screened for their potential antioxidant activities using tests such as electron donating ability (EDA), glutathione S-transferase (GST). The total polyphenol contents of Citrus unshiu extracts were $928.48{\pm}1.19{\mu}g\;GAE/mL$ in ethyl acetate (EA), $886.03{\pm}0.44{\mu}g\;RE/mL$ in acetone (AC), $413.08{\pm}1.39{\mu}g\;GAE/mL$ in methylene chloride (MC), $12,648.60{\pm}0.56{\mu}g\;GAE/mL$ in methanol (MeOH), respectively. Also, the total polyphenol contents of EtOH Citrus unshiu extracts were $664.64{\pm}0.74{\mu}g\;GAE/mL$ in EA, $702.67{\pm}0.85{\mu}g\;RE/mL$ in AC, $429.64{\pm}0.61{\mu}g\;GAE/mL$ in MC, $16,108{\pm}0.73{\mu}g\;GAE/mL$ in MeOH, respectively. The total polyphenol contents were significantly difference (p<0.05) between the solvents. The electron donating ability of Citrus unshiu extracts were $62.80{\pm}0.36%$ in EA, $97.43{\pm}0.51%$ in AC, $52.20{\pm}0.30%$ in MC, $97.63{\pm}0.46%$ in MeOH, respectively. Also, the electron donating ability of EtOH Citrus unshiu extracts were $51.49{\pm}0.26%$ in EA, $63.17{\pm}0.31%$ in AC, $67.68{\pm}0.55%$ in MC, $96.18{\pm}0.41%$ in MA, respectively. The electron donating ability were significantly difference (p<0.05) between the solvents. The inhibitory activity of glutathione S-transferase in Citrus unshiu extracts were $76.22{\pm}0.65%$ in EA, $31.73{\pm}0.48%$ in MC, $97.48{\pm}0.56%$ in MeOH, respectively. Also, inhibitory activity of glutathione S-transferase in EtOH Citrus unshiu extracts were $75.54{\pm}0.55%$ in EA, $73.53{\pm}0.38%$ in MC, $48.70{\pm}0.46%$ in MeOH, respectively. The inhibitory activity of glutathione S-transferase were significantly difference (p<0.05) between the solvents. These results indicated that the Citrus unshiu extracts is a high-valued food ingredient and the extraction with methanol will be useful as a nutritional source with natural antioxidant activities. Considering high consumer demand beneficial health effects, Citrus unshiu extracts can be utilized to develop functional food health- promoting and natural antioxidant agents.

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

• Proceedings of the Korea Crystallographic Association Conference
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• 2000.11a
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• pp.7-7
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• 2000

• Korean Journal of Environmental Agriculture
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• v.14 no.3
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• pp.329-337
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• 1995

The effect of N-(4-chlorophenyl) maleimide(CPMI), plant growth regulators, and alkylating agents on gluathione(GSH) content and glutathione S-transferase(GST) activity was examined with 3-day-old etiolated sorghum(Sorghum bicolor [L.] Moench) seedlings. The GSH content and GST activity of untreated seedlings were higher in shoots than that in roots. Response of GST activity in coleoptile was significantly greater than in other tissues of sorghum seedling. In CPMI-treated seedlings, GSH content was not significantly different from that in untreated seedlings. CPM treatment resulted in 2.3-fold increase in GST activity measured with metolachlor as substrate in the coleoptile region. In contrast, change in GST activity measured with metolachlor as substrate in the coleoptile region. In contrast, change in GST activity measured with 1-chloro-2, 4-dinitrobenzene did not occur. The increase of GST activity was caused by induction of a GST isozyme, which is substrate-specific to metolachlor. Subsequently, two hypotheses related to metolachlor detoxification were evaluated on the basis of regulation of plant growth regulators and substrate induction of GST activity. In coleoptile, GST activity measured with metolachior was increased to 2.1-and 3.4-fold by both 2, 4-dichlorophenoxyacetic acid(2,4-D) and metolachlor treated at the germination stage of sorghum, respectively. Treatments of 2.4-D and metolachlor also induced isozymes exhibiting the activity toward metolachlor. One of the isozymes was co-eluted with that induced by CPMI. These results indicated that increase in GST activity by CPMI may be partially related to auxin regulation and substrate induction.

• Journal of Microbiology and Biotechnology
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• v.11 no.6
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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.

• Journal of Microbiology
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• v.42 no.4
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• pp.353-356
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• 2004

In a previous study, a gst gene was isolated from the fission yeast Schizosaccharomyces pombe. This gene was dubbed gstI, and was characterized using the gstI -lacZ fusion plasmid pYSH2000. In this work, four additional fusion plasmids, pYSHSDl, pYSHSD2, pYSHSD3 and pYSHSD4, were constructed, in order to carry (respectively) 770, 551, 358 and 151 bp upstream regions from the translational initiation point. The sequence responsible for induction by aluminum, mercury and hydrogen peroxide was located in the range between -1,088 and -770 bp upstream of the S. pombe gstI gene. The same region was identified to contain the nucleotide sequence responsible for regulation by Papl, and has one puta­tive Papl binding site, TTACGTAT, located in the range between $-954\~-947$ bp upstream of the gstI gene. Negatively acting sequences are located between -1,088 and -151 bp. These findings imply that the Papl protein is involved in basal and inducible transcription of the gstI gene in the fission yeast S. pombe.

• Journal of Nutrition and Health
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• v.31 no.6
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• pp.1014-1023
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• 1998

The influences of fish oil and different levels of vitamin I supplement on hepatocellular chemical carcinogenesis have been studied. Male Sprague-Dawley rats received diethylnitrosamine (DEN)(200mg/kg body weight) and were subjected to two-thirds partial hepatectomy to induce murine chemical hepatocarcinogenic procedure. Placental glutathione S-transferase(GST-P) positive foci area, antioxidant enzymes(Cu/Zn-superoxide dismutase(SOD), catalase, glutathione reductase (GR), total- glutathione peroxidase (TGPx), glutathione S -transferase (GST)), glucose 6-phosphatase (G6Pase) activities, and lipid peroxidation of microsomes(thiobarbituric acid reactive substances (TBARS)) were measured. Experimental animals were fed 15% corn or fish oil with 0, 40, 1,000, 10,000IU vitamin E /kg diet for 8 weeks. Vitamin E supplements decreased the area of GST-P positive foci in both groups. The higher the vitamin E levels, the smaller the area of GST-P positive foci were noticed. Compared to 0 IU vitamin E, 40 IU in corn oil and 1,000 IU in fish oil groups were effective in decreasing G57-P positive foci area. Fish oil groups tended to have smaller area of GST-P positive foci. fish oil groups showed lower body weight, lower activities of Cu/Zn-SOD and TGPx, higher TBARS contents, higher activities of GST, catalase, G6Pase, GR and higher liver/body ratio than corn oil groups. As the level of vitamin I increased, GST-P positive foci count, catalase activities, and TBARS tended to decrease. G6Pase activities tended to increase in both groups. At higher vitamin E levels, GST activities tended to decrease in fish oil groups. These results suggest that vitamin I has suppressive offects on hepatocellular chemical carcinogenesis probably through antioxidant eH:cts decreasing TBARS contents, $H_2O$$_2$, and organic peroxides. fish oil tended to have greated suppressive offects than corn oil on hepatocellular carcinogenesis. (Korean J Nutrition 31(6) : 1014-1023, 1998)

• Clinical and Experimental Pediatrics
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• v.51 no.3
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• pp.262-266
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• 2008

Purpose : Glutathione S-transferase (GST) is a polymorphic supergene family of detoxification enzymes that are involved in the metabolism of numerous diseases. Several allelic variants of GSTs show impaired enzyme activity and are suspected to increase the susceptibility to diseases. Bilirubin is bound efficiently by GST members. The most commonly expressed gene in the liver is GSTM1, and GSTT1 is expressed predominantly in the liver and kidneys. To ascertain the relationship between GST and neonatal hyperbilirubinemia, the distribution of the polymorphisms of GSTT1 and GSTM1 were investigated in this study. Methods : Genomic DNA was isolated from 88 patients and 186 healthy controls. The genotypes were analyzed by polymerase chain reaction (PCR). Results : The overall frequency of the GSTM1 null was lower in patients compared to controls (P=0.0187, Odds ratio (OR) =0.52, 95% confidence interval (CI), 0.31-0.88). Also, the GSTT1 null was lower in patients compared to controls (P=0.0014, OR=0.41, 95% CI=0.24-0.70). Moreover, the frequency of the null type of both, in the combination of GSTM1 and GSTT1, was significantly reduced in jaundiced patients (P=0.0008, OR=0.31, 95% CI=0.17-0.61). Conclusion : We hypothesized that GSTM1 and GSTT1 might be associated with neonatal hyperbilirubinemia. However, the GSTT1 and GSTM1 null type was reduced in patients. Therefore the null GSTT1, null GSTM1, and null type of both in the combination of GSTM1 and GSTT1 may be not a risk factor of neonatal jaundice.