• The Korean Journal of Pesticide Science
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• v.7 no.1
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• pp.38-44
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• 2003

In vitro inhibitory activity of 34 insecticides and 31 fungicides to glutathione-S-transferase and esterases extracted from rats was determined. Of tested pesticides, the pesticides with high activity on both detoxifying enzymes were mixed with pesticides that are known to be detoxified by detoxifying enzymes. Glutathione-S-transferase was inhibited by thiodicarb $(I_{50}:1.87\times10^{-4}M)$, thiocyclam $(7.40\times10^{-4}M)$, dithianon $(7.55\times10^{-5}M)$, and tolylfluanide $(8.66\times10^{-5}M)$, while esterases by dichlorvos $(8.95\times10^{-8}M)$, pirimicarb $(2.74\times10^{-6}M)$, pyrazophos $(3.31\times10^{-5}M)$, and benomyl $(4.96\times10^{-5}M)$. After acephate known to be detoxified by glutathione-S-transferase was mixed with glutathione-S-transferase-inhibiting pesticides and phenthoate known to be detoxified by esterases was mixed with esterases-inhibiting pesticides, insecticidal activities of such mixtures were determined against diamondback moth (PlutelLa xylostella L.). Synergistic action was observed in all pesticide combinations. The highest synergistic action was obtained when phenthoate was combined with dichlorvos, showing that co-toxicity coefficients were 1512 and 1877 after 24 and 48 hours of treatment, respectively. Several other combinations of pesticides, such as phenthoate with benomyl, and acephate with dithianon, also showed synergism, showing that their co-toxicity coefficients were about 1,000 and 500, after 24 hours of treatment, respectively. Our results showed that combinations of pesticides inhibited by detoxifying enzymes and ones detoxified by detoxifying enzymes resulted in increased toxicities of pesticides, suggesting that such combinations could be used to develop pesticide mixtures with more broad spectrum and high effectiveness.

• Journal of the East Asian Society of Dietary Life
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• v.6 no.1
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• pp.41-49
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• 1996

This research was performed to Investigate the effects of green tea on the lipid composition of serum and liver and the specific activities of antioxidative enzymes. Male Sprague Dawley rats were fed 10% fat diet with lard and fish oil. Powdered green tea was added to the lard and fish oil diet at the level of 0.1% and 1%. After 6 weeks of feeding, serum and liver were obtained from experimental rats. Then we measured the concentration of total cholesterol, HDL-cholesterol and triglyceride. From liver cytosolic fraction, we analized the specific activities of superoxide dismutase, glutathione peroxidase and glutathione S-transferase. The level of total cholesterol and triglyceride were decreased and the ratio of HDL-cholesterol to total cholesterol was increased by the fish oil in the serum. But in the liver, the level of total cholesterol was increased by the fish oil and green tea than the lard. The specific activities of glutathione S-transferase were more increased in the fish oil than the lard. There was not effect of the green tea of daily dose on the lipid composition of serum and liver and the specific activities of antioxidative enzymes in rats.

• Archives of Pharmacal Research
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• v.12 no.4
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• pp.257-258
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• 1989

Glutathione was converted by $HNO_2$ into a S-nitrosothiol which was stable in solution and atypically so even as a solid. FAB/MS and IR data have been obtained for the confirmation of structure of S-nitrosogulathione in the crystalline state.

• Toxicological Research
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• v.11 no.1
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• pp.31-36
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• 1995

Cyclophosphamide (CP) must be enzymatically activated by cytochrome P450(CYP)-linked mixed-function oxidation pathway to be either mutagenic or teratogenic. Influences of alterations in hepatic mixed-function oxidase acitivity and glutathione (GSH) content on the embryotoxicity of CP were studied in rat whole embryo culture system. The embryotoxicity of CP was compared using rat S-9 fraction (S-9) pretreated with chemicals inducing different CYP isozymes, acetone (ACE), Aroclor 1254 (ARO), $\beta$-naphthoflavone (NAF) and phenobarbital (PHE). When 10.5 day embryos were cultured in the immediately centrifuged rat serum for 48 hrs using general gas char{ging schedule, CP$(40{\mu}g/ml)$ with S-9 induced by either NAF or PHE increased the incidence of realformations and significantly decreased embryonic growth compared with the non-induced S-9 group. ACE or ARO induced S-9 group showed no significant difference in embryonic growth. These data suggest that PB and/or NAF inducible CYP isoenzymes are mainly involved in the activation of CP. To examine the effect of GSH on the embryotoxicity of CP, 10.5 day embryos were exposed to CP and S-9 after preincubation with 10 mM of GSH for 3 hrs. In the GSH pretreated group the growth of embryos increased significantly compared with that of the untreated group, suggesting that GSH may protect embryos in culture from some toxic effects of CP.

• Korean Journal of Environmental Biology
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• v.18 no.1
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• pp.41-45
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• 2000

Which sublethal cadmium pretreatment may prevent from lethal cadmium's killing mice and which cadmium pretreatment-induced protection against cadmium lethality to mice may be related with their hepatic glutathione contents were investigated. When cadmium chloride was subcutaneously injected to mice (ICR strain) at various doses, all mice died, which treated with cadmium at dose of 300 $\mu$moles/kg or more, and none died, which treated with cadmium at dose of 80 $\mu$moles/kg or less. Subcutaneous pretreatment of sublethal cadmium decreased sacrifice of mice which subsequently injected with lethal cadmium, with most effectiveness at pretreatment dose of cadmium of 40 $\mu$moles/kg b.w. and at 48 hours of interval between sublethal cadmium pretreatment and lethal cadmium treatment. Even if a great part of the cadmium-pretreated mice were sacrificed while treated with lethal cadmium, they survived longer than the non-pretreated mice. Sublethal cadmium pretreatment (40 $\mu$moles/kg b.w.) 48 hours before lethal cadmium treatment to mice didn't decrease hepatic glutathione contents of the survived mice, while decreases in the glutathione in livers were observed in the mice just after died. These results indicate that sublethal cadmium pretreatment-induced protection against cadmium lethality to mice may be related to their hepatic glutathione contents. [Cd pretreatment, Cd lethality, Hepatic glutathione contents].

• BMB Reports
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• v.29 no.2
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• pp.111-115
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• 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 $45^{\circ}C$.

• Journal of Microbiology
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• v.41 no.3
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• pp.219-223
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• 2003

The toxicity of chlorothalonil on the growth of yeasts was investigated using several yeast strains. An alcohol tolerant yeast, Saccharomyces cerevisiae F38-1, was the most chlorothalonil-tolerant. The glutathione content and the glutathione S-transferase activity were related to the chlorothalonil-tolerant phenotype. Several thiol compounds affect the dissipation of chlorothalonil. However, there was no significant difference on the effects of chlorothalonil dissipation among the thiol compounds tested. The growth of yeast cells was arrested by chlorothalonil. It took about 13 h to dissipate 1 mg/l of chlorothalonil, and the growth was restored as the chlorothalonil content decreased. The glutathione content and glutathione S-transferase are suggested to be among the most important factors of yeast resistance to chlorothalonil.

• Biomolecules & Therapeutics
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• v.21 no.5
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• pp.358-363
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• 2013

In the present study, we investigated the effect of intracellular glutathione (GSH) depletion in heart-derived H9c2 cells and its mechanism. L-buthionine-S,R-sulfoximine (BSO) induced the depletion of cellular GSH, and BSO-induced reactive oxygen species (ROS) production was inhibited by glutathione monoethyl ester (GME). Additionally, GME inhibited BSO-induced caspase-3 activation, annexin V-positive cells, and annexin V-negative/propidium iodide (PI)-positive cells. Treatment with rottlerin completely blocked BSO-induced cell death and ROS generation. BSO-induced GSH depletion caused a translocation of PKC-${\delta}$ from the cytosol to the membrane fraction, which was inhibited by treatment with GME. From these results, it is suggested that BSO-induced depletion of cellular GSH causes an activation of PKC-${\delta}$ and, subsequently, generation of ROS, thereby inducing H9c2 cell death.

• 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.

• The Journal of Korean Medicine
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• v.18 no.2
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• pp.355-365
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• 1997

This study was undertaken to examine the effect of Cheongahwan(CAH), being known to reinforce Kidney-yang, on the activities of endogenous antioxidant enzymes and the production of oxygen free radicals in the kidney tissues. Alterations in enzyme activities were observed after in vivo treatment in rats. CAH caused a significant increase in the activities of superoxide dismutase (SOD), glutathione peroxidase and glutathione S-transferase. But catalase activity was not significantly altered by CAH. Treatment in vitro of CAH decreased the production of oxygen free radicals in a dose-dependent fashion. These results suggest that CAH stimulate the activities of antioxidant enzymes and inhibit directly the production of oxygen free radicals. These effects of CAH may contribute to prevent the oxygen free radical-induced impairment of cell function.