• Toxicological Research
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• 제17권
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• pp.145-155
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• 2001

Cytochrome P4502C19 (CYP2C19) is one of human polymorphic xenobiotic-metabolizing enzymes. The enzyme has been reported to catalyze more than 70 substrates, involving more than 100 reactions. These include several classes of therapeutic agents (e.g. anti-microbial. cardiovascular, psycho-active, etc.), sex hormones and insecticides. Associations of the CYP2C19 genotype/phenotype with individual differences in drug efficacy (e.g. diazepam, omeprazole, proguanil) and toxicity (e.g. mephenytoin, barbiturates) have been documented by many investigators. At least 11 allelic variants of CYP2C19 gene were reported to date. Most of the mutant alleles found in the poor metabolizer (PM) led to the production of truncated and/or inactive proteins. Except for the exon 6, single-nucleotide mutations were reported in all nine exons of the gene. Genetic polymorphism of CYP2C19 shows marked interethnic variation with the population frequencies of PM phenotype ranging from 1∼2% up to more than 50%. The prevalence of CYP2C19 PM tends to be higher in Asian and certain Pacific Islanders than other race or ethnic specificity. Genotyping results of CYP2C19 also revealed that there are different proportions of individual mutant alleles among ethnic populations. This may, in part, explains the interethnic difference in the metabolism of certain drugs (i.e. diazepam), though they were from the same CYP2C19 phenotype. Recently, our research group has studied the genotype and phenotype of CYP2C19 and found that the PM frequency (7∼8%) in Thais is lower than other Asian populations. Molecular and clinical impacts of this finding warrant to further investigation.

• 대한한방내과학회지
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• 제32권2호
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• pp.188-202
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• 2011

Objectives : Oxidative stress seems to play a major role in mechanisms by which ethanol causes liver injury. Previous studies have shown that treatment with Chungganhaeju-tang (Qingganjiejiu-tang, CGHJT) has protective effects on alcoholic liver disease. The aim of this study was to investigate the effects of Chungganhaeju-tang on oxidative stress. Materials and Methods : In vitro, we evaluated the inhibitory activities of CGHJT on DPPH (1,1-diphenyl-2-picryl-hydrazyl), xanthine oxidase, trypsin, and hyaluronidase, and measured cell viability, and proliferation. In the cell culture model, we measured the activities of superoxide dismutase (SOD), and catalase (CAT) after CGHJT treatment in C34 and E47 cell lines, HepG2 cells transfected with/without the cytochrome P450 2E1 (CYP2E1) gene. In vivo, we measured malondialdehyde levels in the liver tissue and alcohol concentration in the blood. Results : CGHJT showed significant free radical scavenging activity against DPPH and xanthine oxidase in the in vitro study, and increased cell viability, proliferation, and activities of superoxide dismutase, catalase in C34 and in E47 cell lines. CGHJT reduced malondialdehyde levels and blood alcohol concentration in vivo, as well. Conclusions : This study suggests that CGHJT has antioxidant effects on oxidative stress by reducing lipid peroxidation and inhibiting the ethanol induced suppression of antioxidant enzyme activities.

• 농업과학연구
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• 제45권2호
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• pp.248-257
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• 2018

Overexpression of AtCYP78A7, a gene encoding a cytochrome P450 protein, has been reported to improve tolerance to drought stress in genetically modified (GM) rice (Oryza sativa L.). The aim of this study was to evaluate the potential allergenicity and acute oral toxicity of the AtCYP78A7 protein expressed in GM rice. Bioinformatics analysis of the amino acid sequence of AtCYP78A7 did not identify any similarities with any known allergens or toxins. It showed that no known allergen had more than a 35% amino acid sequence homology with the AtCYP78A7 protein over an 80 amino acid window or more than 8 consecutive identical amino acids. The gene encoding the AtCYP78A7 protein was cloned in the pGEX-4T-1 vector and expressed in E. coli. Then, the AtCYP78A7 protein was purified and analyzed for acute oral toxicity. The AtCYP78A7 protein was fed at a dose of 2,000 mg/kg body weight in mice, and the changes in mortalities, clinical findings, and body weight were monitored for 14 days after the dosing. Necropsy was carried out on day 14. The protein did not cause any adverse effects when it was orally administered to mice at 2000 mg/kg body weight. These results indicate that the AtCYP78A7 protein expressed in GM rice would not be a potential allergen or toxin.

• Toxicological Research
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• 제17권
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• pp.299-304
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• 2001

Xenobiotics and their reactive intermediates bind to cellular macromolecules and/or generate oxidative stress. which provoke deleterious effects on the cell function. Induction of xenobiotic-biotrans-forming enzymes and antioxidant molecules is an important defense mechanism against such insults. A group of genes involved in the defense mechanism. e.g. genes encoding glutathione S-transferases. NAD(P)H: quinone oxidoreductase, UDP-glucuronosyltransferase (UDP-GT) and ${\gamma}$-glutamylcysteine synthetase (GGCS). have a common regulatory sequence, Antioxidant or Electrophile Responsive Element (ARE/EpRE). Recently. Nrf2. discovered as a homologue of erythroid transcription factor p45 NF-E2, was shown to bind ARE/EpRE and induce the expression of these defense genes. Mice that lack Nrf2 show low basal levels of expression and/or impaired induction of these genes. which makes the animals highly sensitive to xenobiotic toxicity. Indeed. we show here that nrf2-deficient mice had a higher mortality than did the wild-type mice when exposed to acetaminophen (APAP). Detailed analyses of APAP hepatotoxicity in the nrf2 knockout mice indicate that a large amount of reactive APAP metabolites was generated in the livers due to the impaired basal expression of two detoxifying enzyme genes, UDP-GT (Ugt1a6) and GGCS. while the cytochrome P450 content was unchanged. Thus. the studies using the nrf2 knockout mice clearly demonstrate significance of the expression of Nrf2-regulated enzymes in protection against xenobiotic toxicity.

• 생명과학회지
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• 제17권3호통권83호
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• pp.334-339
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• 2007

본 연구는 우황청심원을 비롯한 상용되는 20종의 한약제제를 대상으로 9종의 시토크롬 동종효소에 대한 대사능의 저해정도를 고속 스크리닝 기법을 이용하여 탐색함으로써, 한약제제와 약물의 병용으로 인한 약물 상호작용 가능성을 평가하고자 하였다. 인체 간 마이크로좀 시료에 9종의 주요 시토크롬 약물대사효소의 지표약물과NADPH-generating system및 한약제제(500 ${\mu}g/ml$)를 첨가한 후 $37^{\circ}C$에서 15분간 반응시켜 생성된 각각의 대사물을 LC/MS/MS를 이용하여 정량하여 시토크롬 동종효소 활성의 변화를 평가하였다. 그 결과 우황청심원 현탁액 및 황련해독탕 물 추출물이 각각 CYP2B6 및 CYP2D6 효소 활성을 선택적으로 강력하게 저해하였다. 이러한 결과는 약국에서 쉽게 구입할 수 있는 한약제제들 중 일부는 인체 간 시토크롬 활성 저해능을 가지고 있고, 이들 효소에 의해 대사되는 약물과의 병용 복용시 약물상호작용 발생 가능성이 있음을 의미한다. 향후 한약제제에서 저해능을 나타내는 주된 성분을 규명하여 이 성분의 저해능과 저해 기전을 살피는 노력이 필요할 것이다.

• Journal of Ginseng Research
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• 제43권2호
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• pp.196-208
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• 2019

Background: Nonalcoholic steatohepatitis (NASH) is one of the chronic inflammatory liver diseases and a leading cause of advanced liver fibrosis, cirrhosis, and hepatocellular carcinoma. The main purpose of this study was to clarify the effects of GBCK25 fermented by Saccharomyces servazzii GB-07 and pectinase, on NASH severity in mice. Methods: Six-wk-old male mice were fed either a normal diet (ND) or a Western diet (WD) for 12 wks to induce NASH. Each group was orally administered with vehicle or GBCK25 once daily at a dose of 10 mg/kg, 20 mg/kg, 100 mg/kg, 200 mg/kg, or 400 mg/kg during that time. The effects of GBCK25 on cellular damage and inflammation were determined by in vitro experiments. Results: Histopathologic analysis and hepatic/serum biochemical levels revealed that WD-fed mice showed severe steatosis and liver injury compared to ND-fed mice. Such lesions were significantly decreased in the livers of WD-fed mice with GBCK25 administration. Consistently, mRNA expression levels of NASH-related inflammatory-, fibrogenic-, and lipid metabolism-related genes were decreased in the livers of WD-fed mice administered with GBCK25 compared to WD-fed mice. Western blot analysis revealed decreased protein levels of cytochrome P450 2E1 (CYP2E1) with concomitantly reduced activation of c-Jun N-terminal kinase (JNK) in the livers of WD-fed mice administered with GBCK25. Also, decreased cellular damage and inflammation were observed in alpha mouse liver 12 (AML12) cells and RAW264.7 cells, respectively. Conclusion: Administration of GBCK25 ameliorates NASH severity through the modulation of CYP2E1 and its associated JNK-mediated cellular damage. GBCK25 could be a potentially effective prophylactic strategy to prevent metabolic diseases including NASH.

• Toxicological Research
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• 제31권1호
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• pp.25-32
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• 2015

The objectives of this study were to investigate the individual characteristics, lifestyle habits, exposure levels, and genetic diversity of xenobiotic-metabolizing enzymes involved in toluene metabolism in Korean and foreign workers exposed to toluene at a manufacturing plant. This study was conducted to determine the effects of culture or ethnicity on toluene metabolism. The results showed that blood and urinary toluene concentrations were dependent on the level of exposure to toluene. We analyzed the correlation between toluene metabolism and genetic diversity in glutathione S-transferase (GST) (M1), GSTT1, and cytochrome p-450 (CYP) $2E1^*5$ as well as lifestyle habits (smoking, drinking, and exercise habits). The results revealed significant correlations between toluene metabolism and GSTM1 and GSTT1 genetic diversity, as well as smoking and exercise.

• 생명과학회지
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• 제14권1호
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• pp.38-44
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• 2004

이소플라본의 함량이 매우 높은 것으로 알려진 국내 콩품종 신팔달로부터 2개의 유전자 IFS1 (SinIFS1)과 IFS2(SinIFS2)가 클로닝되었다. 유전자의 염기서열을 밝힌 후, 기존에 알려진 콩과의 다른 IFS 유전자들과 유전자 염기서열의 유사성을 비교 분석하였다. 유전자 SinIFS1은 전체 1,828bp의 nucleotide와 521개의 아미노산으로 이루어져 있었고 SinIFS2의 경우, 1912bp의 nucleotide와 521의 아미노산으로 이루어져 있었다. 두 유전자 모두 cytochrome P45O superfamily의 일원이었고, 상응하는 conserve된 motif들을 가지고 있었다. 콩과의 다른 식물에서 클로닝된 IFS들과의 염기서열비교에서는 매우 높은 염기서열 유사성(98% 이상)이 관측되었다. 유전자의 발현과 유발에 관한 노던분석 실험 결과, 무처리구로 사용한 암처리보다 모두 유발된 유전자의 발현을 나타났는데, 특히 곰팡이 elicitor 처리구의 경우, 무처리보다 6배 이상의 유전자 유발을 보였다. 그 다음으로는 자외선 처리가 높은 유전자 발현 유발효과를 나타내었고, 그 다음으로 저온과 명처리순으로 유발효과를 나타내었다.

• BMB Reports
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• 제43권8호
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• pp.530-534
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• 2010

Cytochrome P450 (CYP) 1A2 gene polymorphisms are thought to be involved in the metabolism of theophylline (TP). We aimed to investigate the effect of CYP1A2*1C, CYP1A2*1D, CYP1A2*1E, and CYP1A2*1F polymorphisms of the CYP1A2 on TP metabolism by PCR-RFLP in 100 Turkish patients with chronic obstructive pulmonary disease (COPD) receiving TP. One hundred and one healthy volunteers were included as control group. The genotype frequencies of the CYP1A2*1D and CYP1A2*1F were found to be significantly different in the patients compared to the controls. The "T" allele at -2467 delT and the "C" allele at -163 C > A in the CYP1A2 displayed association with a significantly increased risk for COPD. "T" allele at -2467 delT was also associated with a high risk of disease severity in COPD. In conclusion, our data suggest that genetic alterations in CYP1A2 may play a role both in the pharmacogenetics of TP and in the development of COPD.

• Asian Pacific Journal of Cancer Prevention
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• 제17권8호
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• pp.4063-4070
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• 2016

Background: Cytochrome P450 2E1 (CYP2E1) and catechol-O-methyltransferase (COMT) genes may contribute to susceptibility to lung cancer because of their critical involvement in mechanisms of carcinogenesis. Materials and Methods: We evaluated the role of CYP2E1 rs2031920 and COMT rs4680 in a case-control study involving 462 lung cancer cases and 379 controls in Japanese. Logistic regression was used to assess adjusted odds ratios (OR) and 95% confidence intervals (CI). Multiplicative and additive interactions with cigarette smoking or alcohol use were also examined. Results: Neither CYP2E1 rs2031920 nor COMT rs4680 was associated with lung cancer risk overall. However, smokers with the CC genotype of CYP2E1 rs2031920 (OR = 3.57, 95% CI = 2.26 - 5.63) presented a higher risk of lung cancer than those with at least one T allele (OR = 2.91, 95% CI = 1.70 - 4.98) as compared to never-smokers with at least one T allele (reference). Subjects with excessive drinking and the CC genotype of CYP2E1 rs2031920 had a significantly higher risk (OR = 2.22, 95% CI =1.39 - 3.56) than appropriate drinkers with at least one T allele. A similar tendency was observed between COMT rs4680 and either smoking or drinking habits. There were no multiplicative or additive interactions between the polymorphisms and either smoking or alcohol use. Conclusions: Our findings indicate that CYP2E1 rs2031920 and COMT rs4680 are not major contributors to lung cancer risk in our Japanese population. Future studies on the genetics of lung cancer in Japanese and their environment interactions are required.