• 한국양식학회지
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• 제19권3호
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• pp.157-165
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• 2006

우리나라 주요 담수 어종인 미꾸라지를 ecotoxicogenomic 연구 모델 어류로 개발하기 위한 연구의 일환으로 본 어종이 고온 스트레스 자극에 노출되었을때 야기되는 산화성 스트레스를 검출하고자 항산화 효소(antioxidant enzyme; AOE) 유전자의 발현 양상을 분석하였다. 주요 항산화 효소인 superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST) 및 glutathione peroxidases (GPXs)의 transcript들을 특이적으로 정량화할 수 있는 semi-quantitative RT-PCR, real-time PCR 또는 northern blot분석을 통해 $23^{\circ}C$에서 $32^{\circ}C$까지 설정된 실험어의 간 조직내 AOE유전자들의 mRNA level을 분석하였다. 고온에 노출되었을 때 본 어종의 AOE들은 일반적으로 증가된 유전자 발현 양상을 나타내었고, 특히 SOD (2배)와 plasma GPX (3배) 유전자가 가장 유의적인 mRNA 증가를 나타내었다. GST의 경우 상대적으로 적은 증가량을 나타내었고 CAT의 경우 고온자극에 반응하지 않았다. 본 어종은 $29^{\circ}C$ 이상에서 AOE 유전자의 발현 증가를 나타내었고 $32^{\circ}C$에 노출되었을 때 1일째부터 SOD와 plasma GPX mRNA의 증가가 관찰되었다.

• 대한두경부종양학회지
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• 제18권2호
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• pp.150-156
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• 2002

Objectives: Most of human cancers may result from exposure to environmental carcinogens, and individual effectiveness in the detoxification of these chemicals will influence susceptibility to malignant disease. Glutathione S-Transferases(GSTs) enzymes are involved in the detoxification of active metabolites of many carcinogens from tobacco smoke and may be important in modulating susceptibility to smoke-related cancer. The purpose of this study is to determine the polymorphism of GSTM1, GSTT1, and GSTP1 in control group and head and neck squamous cell carcinoma group of Korean, and to investigate the effect of GSTs polymorphism on the risk of head and neck cancer. Materials and Methods: A hospital-based case-control study was performed with a group of 133 control individual and 136 head and neck squamous cell carcinoma patients. The polymorphisms of GSTs were analysed using polymerase chain reaction in GSTM1 and GSTTl, and polymerase chain reaction-restriction fragment length polymorphism in GSTP1. Results: The relative risk (odds ratio) of GSTM(-) genotype was 1.14(95% CI, 0.70-1.85) compared to GSTM1(+). The odds ratio of GSTTl(-) genotype was 0.91(95% CI, 0.55-1.50). In old age($65$) group, the odds ratio of GSTT1(-) genotype was 5.2(95% CI, 1.53-17.89). The GSTP1 Val/Val genotype conferred a 1.7-fold risk(95% CI, 0.40-7.34) of head and neck cancer compared with GSTP1 Ile/Ile genotype. Among the combined genotypes of GSTs, GSTM1(-)/GSTT1(+)/GSTP1 Val/Val and GSTM1(-)/GSTTl(-)/GSTP1 Ile/Val genotypes conferred a 2.6-fold and 1.3-fold risk(95% CI, 0.24-14.15 and 0.43-3.14) compared with the GSTM1(+)/GSTTl(+)/GSTP1 Ile/Ile genotype, respectively. Conclusion: Polymorphism of GSTs might modulate susceptibility to head and neck cancer in Korean population. The genotype of GSTP1 Val/Val and combined genotypes of GSTM1(-)/GSTT1(+)/GSTP1 Val/Val, and GSTM1(-)/GSTT1(-)/GSTP1 Ile/Val might be important risk factors to determine the individual susceptibility to head and neck squamous cell carcinoma.

• Bulletin of the Korean Chemical Society
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• 제34권9호
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• pp.2671-2674
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• 2013

To elucidate the role of the evolutionarily conserved Tyr8 residue in rice Phi-class GSTF3, this amino acid was replaced with alanine and phenylalanine by site-directed mutagenesis, respectively. The replacement of Tyr8 with Ala significantly affected the catalytic activity and the kinetic parameters, whereas the substitutions of Tyr8 with Phe had almost no effect. The Y8A mutant resulted in approximately 90-100% decrease of the specific activity. Moreover, the Y8A mutant resulted approximately in 2-fold increase of $K_m$, approximately 60-80% decrease of $k_{cat}$, and approximately 6.5-fold decrease in $k_{cat}/K_m$. From the pH/log $k_{cat}/K_m$ plot, $pK_a$ values of the GSH in the wild-type enzyme-GSH complex, Y8A-GSH complex and Y8F-GSH complex were estimated to be approximately 6.8, 8.5 and 6.9, respectively. From these results, we suggest that the evolutionarily conserved Tyr8 residue in OsGSTF3 seems to influence the structural stability of the active site of OsGSTF3 rather than directly its catalytic activity.

• Clinical and Experimental Reproductive Medicine
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• 제31권2호
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• pp.141-147
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• 2004

Objective: To investigate the association between endometriosis and polymorphisms of N-acetyl transferase 2 (NAT2), glutathione S-transferase M1 (GSTM1), and cytochrome P450 (CYP) 1A1 genes in Korean infertile patients. Materials and Methods: A total of 303 infertile patients who had undertaken diagnostic laparoscopy during January, 2001 through December, 2003 at Samsung Cheil Hospital enrolled in this study. The patients were grouped according to laparoscopic findings: minimal to mild endometriosis (group I: n=147), moderate to severe endometriosis (group II: n=57), normal pelvic cavity (n=99). Peripheral blood was obtained and genomic DNA was extracted. The genotypes of each genes were analyzed using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). For NAT2, RFLP was used to detect the wild type (wt) and mutant (mt) alleles, enabling classification into slow (mt/mt) or fast (wt/wt or wt/mt) acetylation genotypes. For GSTM1, PCR was used to distinguish active (+/- or +/+) from null (-/-) genotypes. For CYP1A1, MspI digestion was used to detect the wild type (A1A1), heterozygote (A1A2) or mutant (A2A2) genotypes. Result: The genotype frequencies of NAT2 slow acetylator was 12.8%, 10.9%, 12.8% in group I, group II and control, respectively. The genotype frequencies of GSTM1 null mutation was 55.3%, 41.8%, 53.2% in group I, group II and control, respectively. The genotype frequencies of CYP1A1 MspI polymorphism was 16.3%, 9.1%, 18.1% in group I, group II and control, respectively. No significant difference was observed between endometriosis and normal controls in the genotype frequencies of the NAT2, GSTM1, CYP1A1 MspI polymorphism. Conclusion: The NAT2, GSTM1, CYP1A1 gene polymorphism may not be associated with the susceptibility of endometriosis in Korean women.

• BMB Reports
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• 제31권3호
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• pp.287-295
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• 1998

Acetolactate synthase (ALS) is the first common enzyme in the biosynthesis of L-Ieucine, L-isoleucine, and L-valine. The sulfonylurea-resistant ALS gene from Nicotiana tabacum was cloned into the bacterial expression vector pGEX-2T. The resulting recombinant plasmid pGEX-ALS3 was used to transform Escherichia coli strain XL1-Blue, and the mutant tobacco ALS (mALS) was expressed in the bacteria as a protein fused with glutathione S-transferase (GST). The fusion product GST-mALS was purified in a single step on a glutathione-Sepharose column. ALS activities of 0.9-2.5 ${\mu}mol/min/mg$ protein were observed in the GST-mALS, and the Km values for pyruvate, FAD, and TPP were 10.8-24.1, $(1.9-8.9){\times}10^{-3}$, and 0.14-0.38 mM, respectively. The purified GST-mALS was resistant to both the sulfonylurea and the triazolopyrimidine herbicides, and lost its sensitivity to end products, L-valine and L-leucine. For comparision, the tobacco wild-type recombinant ALS fused with GST, GST-wALS, was also characterized with respect to its pyruvate and cofactor bindings. These results suggest that the purified mutant recombinant tobacco ALS was functionally active, that the mutations resulting in herbicide resistance has affected pyruvate and cofactor bindings," and that the two classes of herbicides interact at a common site on the plant ALS.

• Toxicological Research
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• 제13권4호
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• pp.339-347
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• 1997

Disulfiram (DSF) and diethyldithiocarbamate (DDC), a reduced form of DSF, protect the liver against toxicant-induced injury through inhibition of cytochrome P450 2E1. The effect of DSF and DDC on the levels of major hepatic microsomal epoxide hydrolase (mEH) and glutathione S-transferase (GST) expression was comparatively studied, given the view that these enzymes are involved in terminal detoxification events for high energy intermediates of xenobiotics. Treatment of rats with a single dose of DSF (20-200 mg/kg, po) resulted in 2- to 15-fold increases in the mEH mRNA level at 24 hr with the ED$_{50}$ value being noted as 60 mg/kg. The mEH mRNA level was elevated ~15-fold at 24 hr after treatment at the dose of 100 mg/kg, whereas the hepatic mRNA level was rather decreased from the maximum at the dose of 200 mg/kg, indicating that DSF might cause cytotoxicity at the dose. In contrast to the effect of DSF, DDC only minimally elevated the mEH mRNA level at the doses employed. DSF moderately increased the major GST mRNA levels in the liver as a function of dose, resulting in rGSTA2, rGSTA3/5 or rGSTM1 mRNA levels being elevated 3- to 4-fold at 24 hr post-treatment, whereas the rGSTM2 mRNA level was not altered. DDC, however, failed to stimulate the mRNA levels for major GST subunits, indicating that the reduced form of DSF was ineffective in stimulating the GST the expression. The effect of other organosulfides including aldrithiol, 2, 2'-dithiobis(benzothiazole) (DTB), tetramethylthiouram disulfide (TMTD) and allyl disulfide (ADS) on the hepatic mEH and GST mRNA expression was assessed in rats in order to further confirm the increase in the gene expression by other disulfides. Treatment of rats with aldrithiol (100 mg/kg, po) resulted in a 16-fold increase in the mEH mRNA level at 24 hr post-treatment. DTB, TMTD and ADS also caused 5-, 9- and 12-fold increases in the rnRNA level, respectively, as compared to control. Thus, all of the disulfides examined were active in stimulating the mEH gene in the liver. The organosulfides significantly increased the rGSTA2, rGSTA3, rGSTA5 and rGSTM1 mRNA levels at 24 hr after administration. In particular, aldrithiol was very efficient in stimulating the rGSTA and rGSTM genes among the disulfides examined. These results provide evidence that DSF and other sulfides effectively stimulate the mEH and major GST gene expression at early times in the liver and that DDC, a reduced form of DSF, was ineffective in stimulating the expression of the genes, supporting the conclusion that reduced form(s) of organosulfur compound(s) might be less effective in inducing the mEH and GST genes through the antioxidant responsive element(s).

• Toxicological Research
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• 제17권
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• pp.251-256
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• 2001

The expression of phase II detoxifying enzymes is affected by a variety of compounds and the induction of the enzymes plays an essential role in chemoprevention. A variety of phytochemicals such as sulfur-containing chemoprotective agents (SCC) may trigger cellular signals and activate phase II gene expression through ARE activation. see induces glutathione S-transferases. Studies were conducted to investigate the role of mitogen-activated protein (MAP) kinase and phosphatidylinositol 3-kinase (PI3-kinase) in the induction of GST (e.g. rGSTA2) by sec. We also studied the MAP kinase pathway responsible for the GST expression by see and compared that with the pathway activated by oxidative stress as a result of sulfur amino acids deprivation (SAAD). see inhibited phosphorylation of ERK1/2 although the effect of see on JNK and p38 MAP kinase was minimal. Wortmannin and LY294002. PI3-kinase inhibitors. abolished the increases in rGSTA2 mRNA and protein levels by SCC. Deprivation of cystine and methionine caused oxidative stress in H4IIE cells. as evidenced by a decrease in the reduced glutathione and an increase in prooxidant production. Electrophoretic mobility shift assay revealed that the ARE complex consisting of Nrf-1/2 and Maf proteins was activated 12~48 h. The rGSTA2 mRNA and protein levels were increased by SAAD. Activation of ARE and induction of rGSTA2 were both completely inhibited by PI3-kinase inhibitors. Inhibition of p38 MAP kinase by SB203580 prevented the ARE-mediated rGSTA2 induction. The results of this study showed that PI3-kinase might play an essential role in the ARE-mediated rGSTA2 induction by see or SAAD and that the dual MAP kinase pathways were responsible for the enzyme induction.

• Preventive Nutrition and Food Science
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• 제6권3호
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• pp.187-191
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• 2001

Effects of kochujang (Korean red pepper soybean paste) extracts on tumor formation, natural killer (NK) cell activity in spleen and glutathione S-transferase (GST) activity in liver were investigated in the sarcoma-180 cell transplanted mice. Inhibitory effects of these samples on lung metastasis of colon 26-M3.1 cells were also evaluated in the Balb/c mice. The injection of methanol extracts from traditional kochujang I (TK I, 0-day fermented), II (TKII, 6-month fermented), commercial kochujang (CK, 1-month fermented) and red pepper powder (RPP) significantly reduced tumor formation in Balb/c mice (p<0.05), TKII decreased tumor growth by 46% compared with control, resulting in the smallest tumor weight. The transplantation of sarcoma-180 cells increased the spleen/body weight ratio of Balb/c mice, while TKI and TKll significantly decreased this index (p<0.05). The effect of TKll and CK, fermented kochujang, on the NK cell activity of splenocytes was higher than that of sarcoma-180 cells transplanted control group. TK II recovered the activity of hepatic GST that was decreased by the transplantation of sarcoma- 180 cells in to the mice. All kochujang-treated mice had significantly fewer lung metastatic colonies than control mice. TKII was the most effective in inhibiting lung metastasis of colon 26-M3.1 cells. These results indicated that optimally ripened (6-month) TK had more suppressive effects on tumor formation and lung metastasis than RPP and kochujang without fermentation and commercially prepared kochujang in mice.

• Archives of Pharmacal Research
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• 제29권3호
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• pp.209-212
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• 2006

We investigated the effect of protein extract of Asterina pectinifera on the activity of 4 enzymes that may playa role in adenocarcinoma of the colon: quinone reductase (QR), glutathione Stransferase (GST), ornithine decarboxylase (ODC), and cyclooxygenase (COX)-2. QR and GST activity increased in HT-29 human colon adenocarcinoma cells increased that had been exposed to 4 concentrations of the protein extract (80, 160, 200, and $240{\mu}g/mL$). Additionally, 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ODC activity decreased significantly in cells exposed to the extract in concentrations of $160{\mu}g/mL$ (p<0.05), $200{\mu}g/mL$ (p<0.005), and $240{\mu}g/mL$ (p<0.005). TPA-induced COX-2 activity also decreased in cells exposed to extract concentrations of 10, 20, 40, and $60{\mu}g/mL$. COX-2 expression was also inhibited in cells exposed to this extract. These results suggest that this protein extract of A pectinifera has chemopreventive activity in HT-29 human colon adenocarcinoma cells, and therefore, may have the potential to function as a chemopreventive agent in human colorectal cancer.

• 한국환경농학회지
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• 제18권3호
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• pp.221-228
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• 1999

본 연구에서는 Bovine bile에서 항산화 물질분획을 분리하고 이에 따른 항산화 효소들의 여러 활성효과를 측정하였으며 GC/FID에 의한 항산화성 물질의 패턴을 확인하였다. 항산화력은 Butylated hydroxy toluene(BHT)에 비해 Bovine bile의 EtOAc추출물(BBE)이 51.2%로 나타났고 xanthine oxidase를 측정 48.3%의 저해효과를 보였으며 glutatione-S-transferase의 활성은 85.7%의 활성이 나타났다. MTT방법에 의한 세포생존율의 조사에서는 6mM glutathione 투여에서 95%라는 생존율과 비교하여 20mg, 60mg의 BBE를 처리했을 때 56%와 65%, 140mg처리에서는 78%의 세포생존율이 나타났다. Bovine bile EtOAc추출물을 TLC로 분석한 결과 Rf값이 0.72에서 항산화 활성이 나타났고 이 분획을 methylation과 trimethysilyl(TMS) 유도체화를 시켜서 Gas Chromatography(FID)와 mass spectrum을 통한 성분 분석을 하고 bile acid의 구성분과 비교하여 계통분석을 실시한 결과 Coprostan-3ol로 추정되었다.