• Microbiology and Biotechnology Letters
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• v.38 no.4
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• pp.475-480
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• 2010

Actinomycetes are Gram-positive soil bacteria and one of the most important industrial microorganisms due to superior biosynthetic capabilities of many valuable secondary metabolites as well as production of various valuable bioconversion enzymes. Among them are cytochrome P450 hydroxylase (CYP), which are hemoproteins encoded by a super family of genes, are universally distributed in most of the organisms from all biological kingdoms. Actinomycetes are a rich source of soluble CYP enzymes, which play critical roles in the bioactivation and detoxification of a wide variety of metabolite biosynthesis and xenobiotic transformation. Cyclosporin A (CyA), one of the most commonly-prescribed immunosuppressive drugs, was previously reported to be hydroxylated at the position of 4th N-methyl leucine by a rare actinomycetes called Sebekia benihana, leading to display different biological activity spectrum such as loss of immunosuppressive activities yet retaining hair growth-stimulating side effect. In order to improve this regio-selective CyA hydroxylation in S. benihana, previously-identified several secondary metabolite up-regulatory genes from Streptomyces coelicolor and S. avermitilis were heterologously overexpressed in S. benihana using an $ermE^*$ promoter-containing Streptomyces integrative expression vector. Among tested, SCO4967 encoding a conserved hypothetical protein significantly stimulated region-specific CyA hydroxylation in S. benihana, implying that some common regulatory systems functioning in both biosynthesis and bioconversion of secondary metabolite might be present in different actinomycetes species.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.6
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• pp.640-645
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• 2004

An eight-week-old male ICR mouse, which was induced with acute alcohol and sub-acute alcohol poisoning condition, was administered with bohee tea(Camelia sinensis L) extract. Under the inducement of the sub-acute alcohol poisoning condition, no considerable differences could be found in the blood alcohol concentration of the positive control group and the bohee tea group(p<0.05). The GOT activity of the three groups: bohee tea, Drink, and Alcodex decreased than that of the normal control group(9.064±4.687 unit)(p<0.05). In addition, the blood GOT activity of the dark green tea group dropped by 81.44% compared with that of the positive control group. On the other hand, the blood GTP activity of the bohee tea group decreased by 5.2% as opposed to that of the positive control and the Drink that decreased by 7.5% as opposed to that of the positive control. The hepatic ADH activity of the bohee tea increased by 22.7%, as opposed to that of the positive control group. The Drink, however, had an increase rate of 33.6%. In the case of the hepatic ALDH activity of the liver, no significant differences were ever recorded among all groups, except for the positive control group. Due to an intake of bohee tea extract, the hepatic ALDH activity decreased by 77.27% which could not be seen in the positive control group. However, Drink and A1codex had a decrease could be seen(p<0.05).

• Journal of the East Asian Society of Dietary Life
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• v.14 no.6
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• pp.634-639
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• 2004

An eight-week-old male ICR mouse, which was induced with acute alcohol and sub-acute alcohol poisoning condition, was administered with bohee tea(Camelia sinensis L) extract. After oral administration of bohee tea and inducement of acute alcohol poisoning condition, the mouses blood alcohol concentration became as low as that of the normal control group. Its decrease rate was 87.26%, in comparison with that of the positive control group. Moreover, its blood GOT activity decreased with a rate of 93.1 % until it reached the normal level, as opposed to that of the positive control group. In addition, the GOT activity, despite rising after the alcohol intake, decreased(p<0.05) significantly after administration of each sample and reached the normal level. The bohee tea group experienced a significant decrease in the GOT activity, compared with the A1codex group and the Drink group. The GPT activity of the Alcodex group decreased by 11 % compared with that of the positive control group. The CTP activity of the bohee tea group decreased by 8.2%, while that of the Drink group decreased by 6.5%(P<0.05). However, there were no significant differences between the results in the control group and those of the test group. The bohee tea group's hepatic ADH activity increased by 22.7% compared with that of the positive control group. On the other hand, the hepatic ADH activity of the Drink group increased by 33.6% while that of the A1codex group increased by 20.4%. On the contrary, the bohee tea extract, the hepatic ALDH did not manifest any significant difference as compared with the normal control group. However, its decrease rate was about 16.67% as compared with that of the positive control group. The Drink group, meanwhile, obtained a decrease rate of about 21.59%.

• Molecules and Cells
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• v.28 no.5
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• pp.479-487
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• 2009

Glutathione reductase (GR) is an enzyme that recycles a key cellular antioxidant molecule glutathione (GSH) from its oxidized form (GSSG) thus maintaining cellular redox homeostasis. A recombinant plasmid to overexpress a GR of Brassica rapa subsp. pekinensis (BrGR) in E. coli BL21 (DE3) was constructed using an expression vector pKM260. Expression of the introduced gene was confirmed by semi-quantitative RT-PCR, immunoblotting and enzyme assays. Purification of the BrGR protein was performed by IMAC method and indicated that the BrGR was a dimmer. The BrGR required NADPH as a cofactor and specific activity was approximately 458 U. The BrGR-expressing E. coli cells showed increased GR activity and tolerance to $H_2O_2$, menadione, and heavy metal ($CdCl_2$, $ZnCl_2$ and $AlCl_2$)-mediated growth inhibition. The ectopic expression of BrGR provoked the co-regulation of a variety of antioxidant enzymes including catalase, superoxide dismutase, glutathione peroxidase, and glucose-6-phosphate dehydrogenase. Consequently, the transformed cells showed decreased hydroperoxide levels when exposed to stressful conditions. A proteomic analysis demonstrated the higher level of induction of proteins involved in glycolysis, detoxification/oxidative stress response, protein folding, transport/binding proteins, cell envelope/porins, and protein translation and modification when exposed to $H_2O_2$ stress. Taken together, these results indicate that the plant GR protein is functional in a cooperative way in the E. coli system to protect cells against oxidative stress.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.325-328
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• 2012

Objective: Glutathione S-transferases (GSTs) are important enzymes that are involved in detoxification of environmental carcinogens. Molecular epidemiological studies have been conducted to investigate the association between GSTM1 and GSTT1 homozygous deletion polymorphisms and brain tumours but results have been conflicting. The aim of this study was to clarify this problem using a meta-analysis. Methods: A total of 9 records were identified by searching the PubMed and Embase databases. Fixed- and random-effects models were performed to estimate the pooled odds ratios. Results: No significant association was found between the GSTM1 and GSTT1 homozygous deletion polymorphisms and risk of brain tumours, including glioma and meningioma. Similar negative results were also observed in both population-based and hospital-based studies. Conclusion: These findings indicate that the GSTM1 and GSTT1 polymorphisms may not be related to the development of brain tumours.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.5
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• pp.750-756
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• 1994

The effect of onion juice on ethanol -induced lipid peroxidation were studied were studied in rats. The contents of thiobarbituric acid (TBA) -reactants increased significantly in liver thanol(4ml/kg/day) administered -rats. The activities of serum alanine aminotransferase and alkaline phosphatase increased by ethanol administration compared with control group, but alterations of antioxidant enzymes activities in liver of ethanol administered rats were not significant vs control group. The glutathione contents in liver decreased by ethanol , whereas the glutathione level increased in ethanol and onion juice group compared with ethanol group. The contents of hepatic TBA-reactants and serum aminotrasnferase activity in ethanol group were reduced by onion juice administration. In these results, increased hepatic TBA-reactants of liver in ethanol group might be due to decreased glutathione contents in liver. Reduced glutathione (GSH) plays an important roles in the liver in several detoxification and the reduction of lipid peroxides. So the protective effects of onion juice on ethanol-induced increment of TBA-reactants may be due to the increament of lgutathions content. The glutathione depletion by ethanol was an important factor of ethanol-induced cell damage, and the prevention of onion juice to the glutathione depletion reduced by ethanol may be an important factor on the protection from ethanol-induced lipid perpxidation in rats.

• BMB Reports
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• v.50 no.2
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• pp.91-96
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• 2017

Nuclear factor erythroid 2-related factor 2 (Nrf2) provides a cellular defense against oxidative stress by inducing the expression of antioxidant and detoxification enzymes. The calcium antagonist, verapamil, is an FDA-approved drug prescribed for the treatment of hypertension. Here, we show that verapamil acts as a potent Nrf2 activator without causing cytotoxicity, through degradation of Kelch-like ECH-associated protein 1 (Keap1), a Nrf2 repressor. Furthermore, verapamil-induced Keap1 degradation is prominently mediated by a p62-dependent autophagic pathway. Correspondingly, verapamil protects cells from acetaminophen-induced oxidative damage through Nrf2 activation. These results demonstrated the underlying mechanisms for the protective role of verapamil against acetaminophen-induced cytotoxicity.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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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.

• Journal of Ginseng Research
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• v.17 no.2
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• pp.123-126
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• 1993

Effects of chronic administration of ginseng extracts (30 or 150 mg/kg/day for 52 days, p.o.) to mice on the activities of DT-diaphorase and glutathione S-transferase (GST) in the liver and the brain were studied. The DT-diaphorase activity in the liver was increased over 2-fold at the dose of both 30 and 150 mg/kg/day, while there was no change in the activity of the enzyme in the brain. The GST activity in the liver was increased in a dose-dependent fashion up to 142% of the control value at the dose of 150 mg/kg/day. while there was no change in the activity of the enzyme in the brain. The ginseng-induced increase in the activities of these hepatic phase II drug-metabolizing enzymes which are involved in the detoxification of carcinogens, is suggested to underlie, at least in part, the anticarcinogenic activity of Panax ginseng.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.87-89
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• 2013

Glutathione S-transferases (GSTs) constitute a multigene family of multifunctional phase II metabolic enzymes. GSTT1, an important member of this group has a wide range of substrates including carcinogens. Total homozygous deletion or null genotype resulting in total lack of enzyme activity exists in populations for this enzyme. Since the null genotype may contribute to lower detoxification of carcinogens, this genotype is expected to increase cancer risk. The frequency of the GSTT1 null genotype is known to vary significantly among populations. However, little is known about its distribution in the hilly Kumaun region of northern India. Therefore, in this study, we determined the prevalence of the GSTT1 null polymorphism in the Kumaun popilation by conducting duplex PCR in 365 voluntary healthy individuals. The GSTT1 null genotype was detected in 18.4% of the individuals. Since GSTs play significant role in xenobiotic metabolism, the present data on GSTT1 genotype distribution should contribute in understanding genetic association with cancer risk in this understudied population.