• 제목/요약/키워드: metabolizing enzyme

검색결과 222건 처리시간 0.034초

Biphenyl dimethyl dicarboxylate (DDB) affects drug metabolizing enzyme, CYP450 in rat liver.

  • Hyon Y. Oh;Kim, Soon S.;Young S. Chang;Yhun. Y. Sheen
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1998년도 Proceedings of UNESCO-internetwork Cooperative Regional Seminar and Workshop on Bioassay Guided Isolation of Bioactive Substances from Natural Products and Microbial Products
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    • pp.142-142
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    • 1998
  • This study has been undertaken to examine the effect of biphenyl dimethyl dicarboxylate (DDB) on rat liver drug metabolizing enzyme in order to understand the mechanism of DDB on improving hepatic toxicity in rat liver. After DDB was administered into male rats for different periods of time, mRNA level of CYP1A1 and CYP2B1 was measured by polymerase chain reaction (PCR). DDB treatment resulted in increase in CYP2B1 mRNA level whereas there was no change in CYP1A1 mRNA level. This effect of DDB was time dependent reaching maximal level by 2-day treatment. DDB dose response study showed that 50mg/kg DDB induced CYP2B1 mRNA to maximal level and DDB icreased CYP2B1 gene expression with dose-dependent manner. Based on studies of lipid peroxidation, serum ALT and AST levels and histopathologic examination showed DDB protection on CCl4 induced hepatotoxiccity.

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반복적인 Betaine 투여가 간독성 및 Cytochrome P-450 의존성 약물대사효소계 활성에 주는 영향 (The Effect of Repeated Betaine Treatment on Hepatotoxicity and Cytochrome P-450 Dependent Drug Metabolizing Enzyme System)

  • 김상겸;김영철
    • 약학회지
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    • 제40권4호
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    • pp.449-455
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    • 1996
  • Betaine is one of the major water-soluble components in Lycii Fructus. In the present study the effect of repeated betaine treatment on the hepatotoxicity and the cytochrome P-4 50-dependent enzyme system was examined in adult female rats. Administrations of betaine (100 or 1,000mg/kg/day, ip) to rats repeatedly for 4 or 9 days did not evoke hepatotoxic response as determined by increases in glutamic pyruvic transaminase(GPT) and glutamic oxaloacetic transaminase(GOT) activities measured 24 hours following the final dose of betaine. The activities of aminopyrine N-demethylase, p-nitroanisole O-demethylase and p-nitrophenol hydroxylase as well as the contents of cytochrome P-450 were determined in hepatic microsomes of rats treated with betaine(1,000mg/kg/day, ip) for 4 or 9 days. Repeated treatment of rats with betaine for a period of 4 days induced a marginal decrease in the contents of cytochrome P-450, but did not influence the activities of p-nitrophenol hydroxylase, p-nitroanisole O-demethylase, or aminopyrine N-demethylase. Extension of the betaine treatment to 9 consecutive days failed to alter the parameters for hepatic drug metabolizing activity determined in the present study. Since repeated large doses of betaine were demonstrated to be tolerated by rats without showing any toxicity or changes in drug metabolizing enzyme activities in the liver, this compound appears to be relatively safe to animals upon long-term ingestion.

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급성 간손상 실험동물에 Cyclohexanone투여가 Oxygen Free Radical 대사효소 활성에 미치는 영향 (Effect of Cyclohexanone Treatment on the Activities of Oxygen Free Radical Metabolizing Enzyme in the Liver Damaged Rats)

  • 김현희;조현성;윤종국
    • 한국환경보건학회지
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    • 제28권2호
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    • pp.81-88
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    • 2002
  • Effect of cyclohexanone treatment on the activities oxygen free radical and cyclohexanone metabolizing enzyme in acute liver damaged rats, was investigated. Acute liver damage was induced in rats with pretreatment of 50% $CCl_4$ in olive oil(0.1ml/100g body wt) intraperitoneally 3 times every other day. Cyclohexanone(1.56g/kg body wt, i.p.) was administered to the animals 24 hours after the last Pretreatment of CC1$_4$. Rats were sacrificed at 4 hours after injection of cyclohexanone. On the basis of liver weight/body weight(%), serum levels alanine aminotransferase activity and hepatic protein content, cyclohexanone treatment to acute liver damaged animals led to the more enhanced liver damage. On the other hand, injection of cyclohexanone to the rats led to the increased activities of hepatic cytochrome P-450 dependent aniline hydroxylase and xanthine oxidase. Furthermore, by treatment of cyclohexanone to the acute liver damaged rats hepatic xanthine oxidase activity was more increased than the $CCl_4$ treated rats. In case of oxygen free radical scavenging system, the hepatic glutathione content and the activities of hepatic glutathione S-transferase, catalase, superoxide dismutase were generally increased by injection of cyclohexanone to rats, and the hepatic glutathione content, catalase and alcohol dehydrogenase activities were more decreased in liver damaged rats by the treatment of cyclohexanone. In conclusion, the cyclohexanone treatment to acute liver damaged rats led to enhancement of liver damage that may be due to oxygen free radical together with cyclohexanone.

재생중인 흰쥐간의 Lipid Peroxidation과 약물대사효소의 상관관계에 관한 연구 (Studies on the Relationship of Lipid Peroxidation and Drug Metabolizing Enzyme in Regenerating Rat Liver)

  • 고기석;최춘근
    • 한국동물학회지
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    • 제27권4호
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    • pp.221-230
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    • 1984
  • Wistar계 흰쥐 간의 약 70%를 절제한 후 재생중인 나머지 간의 microsome에서 lipid peroxidation과 약물 대사효소중 특징적인 aminopyrine demethylase의 활성도를 측정하고 NADPH-cytochrome c reductase, glutathione peroxidase의 활성도와 cytochrome P-450의 함량을 측정하였다. Aminopyrine demethylase의 활성도는 재생 제1일에 최저치를 나타냈으며 재생이 진행될수록 정상인 수준으로 증가하였고 lipid peroxidation, NADPH-cytochrome c reductase, cytochrome P-450의 함량 역시 재생초기에 급히 감소하여 재생2일에 가장 낮은 값을 나타내며 점차 정상인 수준으로 증가하여 7일 이후에는 정상치에 도달하였다. Glutathione peroxidase의 활성도는 재생중인 간이나 정상인 개체의 간에서 별다른 차이가 없었다. 이것은 재생중인 간에서 재생초기에 cytochrome P-450의 함량과 NADPH-cytochrome c reductase의 활성도 감소가 lipid peroxidation과 약물 대사효소의 활성도 감소를 일으키며 이러한 현상은 부분 간 절제 후 7일 이후에는 거의 나타나지 않았다.

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Xylene 대사 효소 활성에 미치는 주.야 시차의 영향 (Effect of Circadian Rhythms on the Xylene Metabolizing Enzyme Activities in Rats)

  • 이혜자;윤종국
    • 한국환경보건학회지
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    • 제27권2호
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    • pp.10-16
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    • 2001
  • To evaluate an effect of circadian variation on the xylene metabolizing enzyme activities, 50% m-xylene in olive oil(0.25 $m\ell$/100g body weight) was intraperitoneally administered to the rats every other day for 6 days both in the night; 24:00 and the day; 12:00. Then animals were sacrigiced at 8hr after last injection of m-xylene. Hepatic microsomal cytochrome p450 contents were more increased both in control and xylene treated rats of night phase than those of day phase. But the activity of hepatic alcohol dehydrogenase(ADH) in control of night phase showed the similar value with that in those of day phase and xylene treated rats of day phase showed an increasing tendency of hepatic ADH activity as those of night phase showing similar activity. Furthermore, control rats of night phase than those of day phase. And by xylene treatment, enzyme activities of rats of day phase were higher tendency in rats of control but those of night phase were somewhat inhibited. Besides, xylene-treated animals of night phase showed increasing tendency of urinary methylhippuric acid concentration compared with those of day phase. On the other hand, liver weight per body weight(%), hepatic lipid peroxide content and serum xanthine oxidase activity were higher in night phase. And the activities of hepatic oxygen free radical metabolizing enzymes such as xanthine oxidase, gluthathione S-transferase, and xylene-treated rats of night phase than those of day phase. In conclusion, it can be hypothesized on the basis of the results that the accumulation rate of m-xylene intermediate metabolite, i.e. m-methylbenzaldehyde in liver tissus may be higher in night phase than in day phase and it may be responsible for higher liver toxicity in bight phase than in day phase.

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Effects of Patriniae Radix and Melandrii Herba on Enzyme Activities in Mice

  • Shin, Kuk-Hyun;Woo, Won-Sick;Lee, Chung-Kyu
    • 생약학회지
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    • 제16권1호
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    • pp.1-6
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    • 1985
  • Effect of various fractions from the roots of Patrinia scabiosaefolia (Valerianaceae) and whole plants of Melandryum firmum (Caryophyllaceae) on enzyme activities in mice was investigated. The butanol fractions from both plants caused a significant elevation of serum transaminase activities when administered intraperitoneally, but did not, orally. Prolonged exposure by oral administration of both plants elevated hepatic cytochrome p-450 content, indicating the induction of drug metabolizing enzymes in liver.

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한국인 두경부암종 환자에서 Cytochrome P450 1A1, 2E1 및 N-acetyltransferase 2 효소의 다형성 분석에 따른 유전적 감수성에 대한 연구 (GENETIC SUSCEPTIBILITIES OF CYTOCHROME P450 1A1, 2E1, AND N-ACETYLTRANSFERASE 2 TO THE RISKS FOR KOREAN HEAD AND NECK CANCER PATIENTS)

  • 이영수;김태균;우순섭;심광섭;공구
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제22권4호
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    • pp.373-382
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    • 2000
  • Individual genetic susceptibilities to cancers may result from several factors including differences in xenobiotics metabolism to chemical carcinogens, DNA repair, altered oncogenes and suppressor genes, and environmental carcinogen exposures. Among them, genetic polymorphisms of metabolizing enzymes to chemical carcinogens have been recognized as a major important host factors in human cancers. They have two main types of enzymes: the phase I cytochrome P-450 mediating enzymes (CYPs) and phase II conjugating enzymes. The purpose of this study is to determine the frequencies of genotypes of phase I (CYP1A1 and CYP2E1) and phase II (NAT2) metabolizing enzymes in healthy control and head and neck cancer patients of Korean and to identify the relative high risk genotypes of these metabolizing enzymes to head and neck cancer in Korean. The author has analyzed 132 head and neck cancer patients and 113 healthy controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The results were as following; 1. The frequencies of genotypes of CYP1A1, CYP2E1 and NAT2 in healthy control were as following; CYP1A1 exon 7 polymorphism; Ile/Ile: Ile/Val: Val/Val = 59.3%: 36.3%: 4.4% CYP2E1 Pst I polymorphism, C1/C1: C1/C2: C2/C2 = 61.1%: 32.1%: 6.2% NAT2 polymorphism; F/F: F/S: S/S = 43.4%: 48.7%: 8.0% 2. In analysis of phase I enzyme, Val/Val genotype in CYP1A1 exon 7 polymorphism and C2/C2 genotype in CYP2E1 Pst I polymorphism were associated with relative high risks to head and neck cancers (Odds' ratio: 2.09 and 1.37, respectively). 3. Among the genotypes of NAT2 enzyme polymorphism, S/S genotype of NAT2 enzyme had 1.03 times of relative risk to head and neck cancers. 4. In combined genotyping of CYP1A1, CYP2E1, and NAT2 enzymes polymorphisms, the patients with Val/Val and C1/C1, C2/C2 and fast acetylator, and Val/Val and fast acetylator had higher relative risks than the patients with each baseline of combined genotypes (Odds' ratio: 2.82, 1.98 and 2.1, respectively). These results suggest the combined genotypes of Val/Val and C1/C1, C2/C2 and fast acetylator, and Val/Val and fast acetylator were more susceptible to head and neck cancers in Korean. And genotyping of metabolizing enzymes could be useful for predicting individual susceptibility to head and neck cancer.

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