• 제목/요약/키워드: Cytochrome P450

검색결과 936건 처리시간 0.024초

Formalin에 약욕시킨 넙치(Paralichthys olivaceus)의 스트레스 반응과 간장 약물대사효소의 경시적 반응 (Time-course Responses of Hepatic Xenobiotic Metabolizing Enzymes and Stress in Olive Flounder (Paralichthys olivaceus) Exposed to Formalin)

  • 이지선;김병기;이경선;전중균
    • 한국양식학회지
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    • 제19권2호
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    • pp.90-94
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    • 2006
  • The effects of formalin on mixed function oxygenase (MFO) system and stress-response were investigated in olive flounder (Paralichthys olivaceus). Olive flounder was exposed to formalin at the concentration of 300 ppm for 1, 2, 4 and 16 h. Levels of stress-response enzymes together with total protein, glucose and osmolality were quantitatively determined in blood, and the activities of phase I (cytochrome P450, ethoxyresorufin deethylase) and phase II (glutathione S-transferase) hepatic enzymes were also determined. Since the formalin-exposure for 16 h resulted no significant changes in aspartate aminotransferase and alanine aminotransferase, specific enzymes for liver damage, it was thought that it did not cause hepatic tissue damage at the concentration of 300 ppm. However, hepatic MFO system was induced at 1 to 4 h, and stress response was induced after 16 h of exposure. Moreover, it is considered that the depression of MFO activity after 16 h of exposure may not be adaptation to formalin, but toxic response. These results suggest that low concentration of formalin does not cause hepatic tissue damage of fish, but could induce MFO and stress response.

Protective Effect of Dandelion Extracts on Ethanol-Induced Acute Hepatotoxicity in C57BL/6 Mice

  • Liu, Xiao-Yu;Ma, Jie;Park, Chung-Mu;Chang, Hee-Kyung;Song, Young-Sun
    • Preventive Nutrition and Food Science
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    • 제13권4호
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    • pp.269-275
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    • 2008
  • Dandelion (Taraxacum officinale) has been widely used as an anti-inflammatory agent in oriental medicine. In the current study, we investigated the protective effect, and the possible mechanism, of dandelion extracts against ethanol-induced acute hepatotoxicity in C57BL/6 mice. Dandelion water and ethanol extract was administered at 2 g/kg body weight (BW) once daily for 7 consecutive days, whereas control and ethanol groups received water by gavage. Ethanol (50% ethanol; 6 g/kg BW) was administered 12 hr before sacrificing the mice in order to generate liver injury. Significantly increased serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities as well as liver triglyceride (TG) and cholesterol levels were attenuated by dandelion supplementation. In addition, dandelion extracts not only enhanced alcohol dehydrogenase (ADH) and anti-oxidative enzyme activities, but reduced lipid peroxidation. Cytochrome P450 2E1 (CYP 2E1), one of the critical enzymes xenobiotic metabolism, expression was lower with ethanol treatment but restored by dandelion supplementation. These results were confirmed by improved histopathological changes in fatty liver and hepatic lesions induced by ethanol. In conclusion, dandelion could protect liver against ethanol administration by attenuating of oxidative stress and inflammatory responses.

Four Polymorphisms in the Cytochrome P450 1A2 (CYP1A2) Gene and Lung Cancer Risk: a Meta-analysis

  • Bu, Zhi-Bin;Ye, Meng;Cheng, Yun;Wu, Wan-Zhen
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권14호
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    • pp.5673-5679
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    • 2014
  • Background: Previous published data on the association between CYP1A2 rs762551, rs2069514, rs2069526, and rs2470890 polymorphisms and lung cancer risk have not allowed a definite conclusion. The present meta-analysis of the literature was performed to derive a more precise estimation of the relationship. Materials and Methods: 8 publications covering 23 studies were selected for this meta-analysis, including 1,665 cases and 2,383 controls for CYP1A2 rs762551 (from 8 studies), 1,456 cases and 1,792 controls for CYP1A2 rs2069514 (from 7 studies), 657 cases and 984 controls for CYP1A2 rs2069526 (from 5 studies) and 691 cases and 968 controls for CYP1A2 rs2470890 (from 3 studies). Results: When all the eligible studies were pooled into the meta-analysis for the CYP1A2 rs762551 polymorphism, significantly increased lung cancer risk was observed in the dominant model (OR=1.21, 95 % CI=1.00-1.46). In the subgroup analysis by ethnicity, significantly increased risk of lung cancer was observed in Caucasians (dominant model: OR=1.29, 95%CI=1.11-1.51; recessive model: OR=1.33, 95%CI=1.01-1.75; additive model: OR=1.49, 95%CI=1.12-1.98). There was no evidence of significant association between lung cancer risk and CYP1A2 rs2069514, s2470890, and rs2069526 polymorphisms. Conclusions: In summary, this meta-analysis indicates that the CYP1A2 rs762551 polymorphism is linked to an increased lung cancer risk in Caucasians. Moreover, our work also points out the importance of new studies for rs2069514 associations in lung cancer, where at least some of the covariates responsible for heterogeneity could be controlled, to obtain a more conclusive understanding about the function of the rs2069514 polymorphism in lung cancer development.

다환성방향족탄화수소 노출에 대한 감수성에 미치는 CYP2E1의 작용 (Action-mechanisms of Genetic Polymorphism in the CYP2E1 on Susceptibility to Polycyclic Aromatic Hydrocarbons)

  • 강혁준;박장환;강진선;동미숙;양미희
    • Environmental Analysis Health and Toxicology
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    • 제20권3호
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    • pp.215-221
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    • 2005
  • Environmental polycyclic aromatic hydrocarbones (PAHs), which are formed during incomplete combustion of fossil fuels, are widely distributed in our environment. Human exposure to PAHs may occur through smoking, polluted air, food consumption and occupational contact. Urinary naphthols, 1-and 2-naphthol, have been suggested as route -specific biomarkers for exposure to airborne PAHs. Cytochrome p450 2E1 (CYP2E1) is known to be a great importance for the metabolism of organic solvents, which is a precacinogens with small molecular weight. This study describes the metabolic differences between PstI and RsaI polymorphisms (c1 allele: PstI-. RsaI+ ; c2 allele: PstI+, RsaI-) of CYP2E1 5-flanking region by genetically modified HepG2 cells, which overexpress the polymorphic regions. The results of CAT assay and western blot in the c2 allele overexpressed cells have higher activities than the cl allele over-expressing cells. However, the metabolism of naphthalene to 2-naphthol has no difference due to the two genotypes. In this study, we established the CYP2E1 polymorphic allele transduced HepG2 cells to screen susceptibility -differences in PAH exposure. In conclusion, the CYP2E1 polymorphism may hardly induce susceptibility differences in PAH exposure monitoring with urinary naphthols.

$CC1_4$로 유발된 백서의 간손상에 대한 갈근의 간보호작용 연구 (The Study of Protective Effect of Puerariae Radix against $CC1_4$-induced Hepatotoxicity)

  • 현동환;정선영;정상신;하기태;김철호;김동욱;김준기;최달영
    • 동의생리병리학회지
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    • 제17권2호
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    • pp.297-307
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    • 2003
  • In the present study, we investigated the protective effect of the Puerarie Radix water extract (PRE) against CCl₄-induced hepatotoxicity and the mechanism underlying these protective effects in the rats. The pretreatment of PRE has shown to possess a significant protective effect by lowering the serum alanine and aspartate aminoteansferase (AST and ALT) and alkaline phosphatase (ALP). This hepatoprotective action was confirmed by histological observation. In addition, the pretreatment of PRE prevented the elevation of hepatic malondialdehyde (MDA) formation and the depletion of reduced glutathione (GSH) content and catalase activity in the liver of CC1₄-injected rats. The PRE also displayed hydroxide radical scavenging activity in a dose-dependent manner (IC50 = 83.6 μg/ml), as assayed by electron spin resonance (ESR) spin-trapping technique. Moreover, the expression of cytochrome P450 2E1 (CYP2E1) mRNA, as measured by reverse transcriptase-polymerase chain reaction (RT-PCR), was significantly decreased in the liver of PRE-pretreated rats when compared with that in the liver of control group. Based on these results, it was suggested that the hepatoprotective effects of the PRE may be related to antioxidant effects and regulation of CYP2E1 gene expression.

CYP1B1 Activates Wnt/β-Catenin Signaling through Suppression of Herc5-Mediated ISGylation for Protein Degradation on β-Catenin in HeLa Cells

  • Park, Young-Shin;Kwon, Yeo-Jung;Chun, Young-Jin
    • Toxicological Research
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    • 제33권3호
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    • pp.211-218
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    • 2017
  • Cytochrome P450 1B1 (CYP1B1) acts as a hydroxylase for estrogen and activates potential carcinogens. Moreover, its expression in tumor tissues is much higher than that in normal tissues. Despite this association between CYP1B1 and cancer, the detailed molecular mechanism of CYP1B1 on cancer progression in HeLa cells remains unknown. Previous reports indicated that the mRNA expression level of Herc5, an E3 ligase for ISGylation, is promoted by CYP1B1 suppression using specific small interfering RNA, and that ISGylation may be involved in ubiquitination related to ${\beta}-catenin$ degradation. With this background, we investigated the relationships among CYP1B1, Herc5, and ${\beta}-catenin$. RT-PCR and western blot analyses showed that CYP1B1 overexpression induced and CYP1B1 inhibition reduced, respectively, the expression of $Wnt/{\beta}-catenin$ signaling target genes including ${\beta}-catenin$ and cyclin D1. Moreover, HeLa cells were treated with the CYP1B1 inducer $7,12-dimethylbenz[{\alpha}]anthracene$ (DMBA) or the CYP1B1 specific inhibitor, tetramethoxystilbene (TMS) and consequently DMBA increased and TMS decreased ${\beta}-catenin$ and cyclin D1 expression, respectively. To determine the correlation between CYP1B1 expression and ISGylation, the expression of ISG15, a ubiquitin-like protein, was detected following CYP1B1 regulation, which revealed that CYP1B1 may inhibit ISGylation through suppression of ISG15 expression. In addition, the mRNA and protein expression levels of Herc5 were strongly suppressed by CYP1B1. Finally, an immunoprecipitation assay revealed a direct physical interaction between Herc5 and ${\beta}-catenin$ in HeLa cells. In conclusion, these data suggest that CYP1B1 may activate $Wnt/{\beta}-catenin$ signaling through stabilization of ${\beta}-catenin$ protein from Herc5-mediated ISGylation for proteosomal degradation.

마늘에 의한 사염화탄소 간독성의 보호 효과 (The Protective Effects of Garlic against Carbon tetrachloride-induced Hepatotoxicity)

  • 이종문;박정덕;홍연표;최병선
    • Journal of Preventive Medicine and Public Health
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    • 제35권3호
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    • pp.221-228
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    • 2002
  • Objectives : The purpose of this study was to find the protective effects of garlic on the halogenated hydrocarbon induced hepatotoxicities, and the possible protection mechanisms involved. Methods : Male Sprague-Dawley rats received garlic (0.5%) or regular diet, for 4 weeks. This was followed by a single dose of corn oil (the controls), carbon tetrachloride (400mg/kg body weight) and trichloroethylene (2,000mg/kg body weight) being administered to each diet group. Blood samples were collected 24 hours fellowing the administration, and the serum aspartate aminotransferase (AST) and alanine aminotransferase (ALD activities measured. The liver samples were studied for their cytochrome P450 and CYP2E1 contents, lipid peroxidation and histopathology. Results : rho results for the group receiving the 9.5% garlic diet showed a slight decrease of CYP2E1 expression compared with the regular diet group. Carbon tetrachloride was significantly decreased the CYP2E1 contents in both the regular and garlic diet groups, but the trichloroethylene remained unchanged. Garlic did not decrease the lipid peroxidation of the liver in the control group, but attenuated the increase of lipid peroxidation caused by carbon tetrachloride. Garlic attenuated the increase of both the serum AST and ALT activities caused by carbon tetrachloride. The histopathelogical observations also showed that garlic attenuated centrilobular necrosis and vacuolar degenerative changes significantly in the carbon tetrachloride treated group. Conclusions : The results indicate that garlic attenuates the carbon tetrachloride-induced hepatotoxicity, through the prevention of the metabolic activation and lipid peroxidation.

Gene Expression Analysis of the Bromobenzene Treated Liver with Non-hepatotoxic Doses in Mice

  • Lim, Jung-Sun;Jeong, Sun-Young;Hwang, Ji-Yoon;Park, Han-Jin;Cho, Jae-Woo;Song, Chang-Woo;Kim, Yang-Seok;Lee, Wan-Seon;Moon, Jin-Hee;Han, Sang-Seop;Yoon, Seok-Joo
    • Molecular & Cellular Toxicology
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    • 제1권4호
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    • pp.268-274
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    • 2005
  • Bromobenzene (BB) is well known hepatotoxicant. Also, BB is an industrial solvent that arouses toxicity predominantly in the liver where it causes centrilobular necrosis. BB is subjected to Cytochrome P450 mediated epoxidation followed by either conjugation with glutathione, enzymatic hydrolysis or further oxidation. In this study, we focused on BB-induced gene expression at non-hepatotoxic dose. Mice were exposed to two levels of BB, sampled at 24 h, and hepatic gene expression levels were determined to evaluate dose dependent changes. When examining the toxic dose of BB treated group in other previous studies, genes related to heat shock protein, oxidative stress, and drug metabolism are expressed. Compared to these results, our study, in which non-toxic dose of BB was administrated, showed similar patterns as the toxic conditions above. The purpose of the study was to select genes that showed changes in relation to the differing dose through confirmation of the difference within transcriptomic boundaries, but those that are not detected by the existing classic toxicology tools in non-hepatotoxic dose.

홍삼의 약리와 독성 기전에 대한 고찰 (Review of Red Ginseng in terms of Mechanisms for Pharmacodynamics and Toxicity)

  • 박영철;임정대;김종봉;이선동
    • 대한한의학회지
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    • 제33권3호
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    • pp.200-230
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    • 2012
  • Objectives: Ginseng, Panax ginseng C. A., white ginseng, has been used for thousands of years in Traditional Korean Medicine. Red ginseng can be made by a steaming process of white ginseng changing a variety of ginsenosides and ingredients such as dencichine. This article reviews red ginseng for mechanisms for pharmacodynamics and toxicity based on the content of ginseng's active ingredients, ginsenoside changed by steaming. Methods: The following electronic databases were searched: PubMed, Science Direct and Chinese Scientific Journals full text database (CQVIP), and KSI (Korean Studies Information) from their respective inceptions to June 2012. Results: Compared with unsteamed ginseng, the content of ginsenosides Rg2, Rg3, Rg5, Rh1, Rh2 and Rk1 called red ginseng-specific ginsenosides increased after the steaming process. Different ginsenosides have shown a wide variety of effects such as lowering or raising blood sugar and blood pressure or stimulating or sedating the nervous system. Especially, the levels of Rg2, Rg3, Rg5, Rh1, Rh2 and Rk1 were increased by the steaming process, showing a variety of pharmacodynamics in biological systems. Also, various processing methods such as puffing and fermentation have been developed in processing crude ginseng or red ginseng, affecting the content of ginseng's ingredients. The safety issue could be the most critical, specifically, on changed ginseng's ingredients such as dencichine. The level of dencichine was significantly reduced in red ginseng by the steaming process. In addition, the possible toxicity for red ginseng was affected by cytochrome P450, a herbal-drug interaction. Conclusions: The variety of pharmacological and toxicological properties should be changed by steaming process of Panax ginseng C. A., white ginseng. Even if it is not sure whether the steaming process of white ginseng would be better pharmacologically, it is sure that steaming reduces the level of dencichine causing a lower toxicity to the nervous system.

고혈당(高血糖) 쥐의 간(肝) 대사효소계(代謝酵素系)에 미치는 생진양혈탕(生津養血湯)의 영향(影響) (Effect of SAENGCHINYANGHYOLTANG on the hepatic metabolic enzyme system in streptozotocin-induced diabetic rats)

  • 김신석;이경희;이철완;최종원;김석환
    • 대한한의학회지
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    • 제16권2호
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    • pp.320-336
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    • 1995
  • SANGNYANGHYOLTANG(SYT) is one of the most important prescription that has been used in oriental medicine for diabetes mellitus. The sudy was done in order to elucidate the anti-diabetic effect of SYT. After pretreatment of SYT(1,000mg/kg) for 6 weeks, the effect of of SYT was prevented on serum liver function test and hepatic lipid peroxide content in rats i.v. injected with streptozotocin(STZ, 50mg/kg, tail vein) 5 weeks after pretreatment of SYT. The hepatic microsomal cytochrome P-450 and aniline hydroxylase were significantly decreased, and aminopyrine N-demethylase activity was significantly increased in SYT-STZ group as compared with control group. Changes in aldehyde oxidase, xanthine oxidase, superoxide dismutase, catalase, epoxide hydrolase, UDP-glucuronyltransferase and sulfotransferase activities were not significantly different in any of the group. The cytosolic glutathione S-transferase activity was significantly decreased in SYT-STZ group as compared with control group. The selenium-independent glutathione peroxidase was significantly increased in SYT-STZ group as compared with control group, but there was no significant difference in selenium-dependent glutathione peroxidase in any of the groups. The hepatic glutathione concentration was significantly increased in SYT-STZ group as compared with control group, and ${\gamma}-glutamylcystein$ synthetase and glutathione reductase activities were not significantly different in any of the groups. The hepatic lipid peroxide content, serum aminotransferase and sorbitol dehydrogenase activities were slightly decreased in significantly in SYT-STZ groups.

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