• YAKHAK HOEJI
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• v.47 no.4
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• pp.218-223
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• 2003

Effect of taurine treatment on metabolism of glutathione (GSH) was studied in adult male ICR mice. An acute injection of taurine (250 mg/kg, ip) resulted in a significant decline of hepatic GSH level at t = 6 hr, but plasma GSH level was not altered. The activity of GSH-related enzyme in liver, such as GSH peroxidase, GSSG reductase, GSH S-transferases, ${\gamma}$-glutamylcysteine synthetase or ${\gamma}$-glutamyltranspeptidase, was not affected by taurine at t = 2.5 or 6 hr. Plasma cysteine and cystine levels were elevated rapidly following taurine treatment. Hepatic cysteine level was decreased by taurine, reaching a level approximately 70％ of control at t = 4 and 6 hr. In conclusion, the results indicate that an acute dose of taurine decreases hepatic GSH level by reducing the availability of cysteine, an essential substrate for synthesis of this tripeptide in liver. It is also suggested that taurine may decrease the cysteine uptake by competing with this S-amino acid for a non-specific amino acid transporter.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.157-163
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• 2012

Objective: Glutathione S-transferases (GSTs) are multifunctional enzymes that play a crucial role in the detoxification of both the endogenous products of oxidative stress and exogenous carcinogens. Recent studies investigating the association between genetic polymorphisms in GSTs and the risk of adult brain tumors have reported conflicting results. The rationale of this pooled analysis was to determine whether the presence of a GST variant increases adult glioma susceptibility by combining data from multiple studies. Methods: In our meta-analysis, 12 studies were identified by a search of the MEDLINE, HIGHWIRE, SCIENCEDIRECT and EMBASE databases. Of those 12, 11 evaluated GSTM1, nine evaluated GSTT1 and seven evaluated GSTP1 Ile105Val. Between-study heterogeneity was assessed using ${\chi}^2$-based Q statistic and the $I^2$ statistic. Crude odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were used to estimate the association between GSTM1, GSTT1 and GSTP1 polymorphisms and the risk of adult gliomas. Results: The quantitative synthesis showed no significant evidence to indicate an association exists between the presence of a GSTM1, GSTT1 or GSTP1 Ile105Val haplotype polymorphism and the risk of adult gliomas (OR, 1.008, 1.246, 1.061 respectively; 95% CI, 0.901-1.129, 0.963-1.611, 0.653-1.724 respectively). Conclusions: Overall, this study did not suggest any strong relationship between GST variants or related enzyme polymorphisms and an increased risk of adult gliomas. Some caveats include absence of specific raw information on ethnic groups or smoking history on glioma cases in published articles; therefore, well-designed studies with a clear stratified analysis on potential confounding factors are needed to confirm these results.

• Proceedings of the Korean Society of Toxicology Conference
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• 1998.10a
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• pp.56-56
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• 1998

• Journal of Yeungnam Medical Science
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• v.12 no.1
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• pp.32-47
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• 1995

Glutathione(GSH) has a very important role in detoxification of cells and is closely related to antitumor drug-resistance of cancer cells. In order to evaluate the importance of glutathione metabolism in the drug-resistant cancer cells, the concentration of celluar GSH and activities of ${\gamma}$-glutamylcysteine synthetase(GCS), ${\gamma}$-glutamyl transpeptidase (GGT) and glutathione S-transferases(GST) in the adriamycin, vincristine, or cisplatin resistant L1210 (L1210AdR, L1210VcR, or L1210Cis) sublines were measured. Expression and amplification of GCS, GGT, and GST-${\pi}$ genes were also observed in the parent Ll210 and the drug-resistant Ll210 sublines. The concentration of GSH was increased 5.34 fold in L1210Cis, 2.83 fold in L1210VcR, and 1.78 fold in L1210AdR, compared to L1210. The activities of GCS and GGT were increased in drug-resistant L1210 sublines. The GST activity was increased in L1210VcR and L1210Cis but decreased in L1210AdR compared to Ll210. Expression of GCS, GGT, and GST-${\pi}$ genes were increased in the resistant L1210 sublines compare to the parent L1210 in northern blot analyses. Overexpression of GCS, GGT, and GST-${\pi}$ were observed in the resistant sublines, and the increases of the concentration of glutathione and the activities of GCS and GGT in the resistant sublines may be involved in a part of the drug-resistance in the resistant sublines.

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.05a
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• pp.72-72
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• 2003

Induction of glutathione S-transferases is associated with cancer chemoprevention. We reported that PD98059, an MKK1 inhibitor, induces glutathione Stransferase A2 (rGSTA2). This report comparatively examines the role of CCAAT/enhancer binding protein (C/EBP) and Nrf-2 in the induction of rGSTA2 by PD98059. PD98059 at the concentrations effective for the inhibition of MKKI increased the rGSTA2 protein and mRNA levels in H4IIE cells. (omitted)

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.05a
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• pp.60-61
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• 2003

Effects of repeated treatment with butylated hydroxyanisole (BRA) on the induction of glutathione S-transferases (GSTs) and teratogenicity of cyclophosphamide were investigated in rats. Pregnant rats were orally treated with BRA (50 mg/kg) for 7 days, from days 6 to 12 of gestation, and subcutaneously challenged with cyclophosphamide (15 mg/kg) 2 hr after the final treatment. On day 20 of gestation, the maternal and fetal abnormalities were examined.(omitted)

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.04a
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• pp.68-68
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• 2003

The glutathione-S-transferases (GSTs) are enzymes responsible for the protection of cells from chemical toxicants and oxidative stress. In insects, GSTs have been particularly known to be implicated in the resistance to insecticides. In this study, a cDNA encoding the GST gene homologue was isolated from the cDNA library of the mole cricket, Gryllotalpa orientalis. (omitted)

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.82.1-82.1
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• 2003

The protective adaptive response to electrophiles and reactive oxygen species is mediated by enhanced expression of phase II detoxifying genes including glutathione S-transferases. ${\alpha}$-Lipoic acid, which exerts prooxidant or antioxidant activities, has been shown to activate the insulin signaling pathway and thus to induce insulin-like actions via PI3-kinase and Akt. Our previous studies have shown that PI3-kinase plays an essential role in Nrf2-or C/EBP${\beta}$-mediated glutathione S-transferase A2 (GSTA2) induction. (omitted)

• Korean Journal of Environmental Agriculture
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• v.8 no.1
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• pp.47-54
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• 1989

This study was conducted to investigate insecticide toxicities to a honeybee, Apis cerana F. being raised in Korea and its detoxifying enzyme activities. In order to determine the appropriate usage of insecticides, median effective dose and detoxifying enzyme activities to seven insecticides were observed. Various detoxifying enzymes, including microsomal oxidases, glutathione S-transferases, esterases, and DDT-dehydrochlorinase were assayed in the midguts of adult worker bees as the enzyme source. Of the insecticides used, $LC_{50}$ value in DDT treatment was the highest as 19ppm, and that in EPN treatment was the lowest as 0.75ppm. Sublethal exposures of honeybees to various insecticides had some effects on microsomal enzyme activities. Aldrin epoxidase activity was inhibited by malathion and demeton S-methyl treatment. N-demethylase activity was induced by carbaryl treatment. Of the glutathione S-transferases, aryltransferase(DCNB conjugation) activity was significantly induced by diazinon, and moderately induced by malathion. Of the esterases, ${\alpha}-NA$ esterase activity was moderately inhibited by malathion and permethrin. Carboxylesterase and acetylcholinesterase activity were not affected by the sublethal exposure of honeybee to the insecticides. Sublethal exposure of honeybee to the insecticides had no effect on DDT- dehydrochlorinase activity, except carbaryl, malathion and demeton S-methyl were inhibited.

• Journal of Plant Biotechnology
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• v.35 no.4
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• pp.265-274
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• 2008

Glutathione S-transferases (GSTs) are multifunctional proteins encoded by a large gene family divided into Phi, Tau, Theta, Zeta, Lambda and DHAR classes on the basis of sequence identity. The Phi(F) and Tau(U) classes are plant-specific and ubiquitous. Their roles have been defined as herbicide detoxification and responses to biotic and abiotic stresses. Fifty-two members of the GST super-family were identified in the Arabidopsis thaliana genome, 13 members of which belong to the Phi class of GSTs (AtGSTFs). Based on the sequence similarities of AtGSTFs, 11 BAC clones were identified from Brassica rapa. Seven unique sequences of ORFs designated the Phi class candidates of GST derived from B. rapa (BrGSTFs) were detected from these 11 BAC clones by blast search and sequence alignment. Some of BrGSTFs were present in the same BAC clones indicating that BrGSTFs could also be clustered as usual in plant. They were mapped on B. rapa linkage group 2, 3, 9 and 10 and their nucleotide and amino acid sequences were highly similar to those of AtGSTFs. In addition, in silico analysis of BrGSTFs using Korea Brassica Genome Project 24K oligochip and microarray database for cold, salt and drought stresses revealed 15 unigenes to be highly similar to AtGSTFs and six of these were identical to one of BrGSTFs identified in the BAC clones indicating their expression. The sequences of BrGSTFs and unigenes identified in this study will facilitate further studies to apply GST genes to medical and agriculture purposes.