• 제목/요약/키워드: Xenobiotic metabolism

검색결과 48건 처리시간 0.023초

약물대사효소 CYP2C19, CYP2D6의 다형성과 사상체질의 관련성 연구 (Association between Genetic Polymorphisms of the CYP2C19, CYP2D6 and Types of Sasang Constitutional Medicine)

  • 이상규;김현주;박혜정;이정호;권덕윤;주종천;최선미;이혜숙;김윤경
    • 대한한의학회지
    • /
    • 제28권1호통권69호
    • /
    • pp.51-62
    • /
    • 2007
  • Objectives . The types of Sasang constitutional medicine (SCM) have definite effect on response to herbal drugs. The majority of human P45O dependent xenobiotic metabolism is carried out by polymorphic enzymes which can cause abolished, altered or enhanced metabolism. Therefore, we evaluated the relation of major CYP2C19, 2D6 polymorphism with Sasang types. Methods : 214 healthy subjects were recruited with informed consent; 172 among them had Sasang diagnosis by QSCC2. CYP2D6, 2C19 polymorphism were determined by PCR-RFLP method. Results : None of the Sasang types showed significant difference in CYP2D6, 2C19 polymorphism. However, the Tae-um type showed relatively low frequency of CYP2D6 $^{*}$10/$^{*}$10 polymorphisms with low activity (p=0.110). In the So-yang type, specific $^{*}$3/$^{*}$3 genotype which is a poor metabolizer of CYP2C19$^{*}$3 was detected (p=0.078).Conclusion . These results suggest that the Tae-um type which is said to have high liver function in SCM has the tendency of high drug-metabolizing enzyme activity. With further study, the CYP polymorphism could serve as a scientific tool for SCM diagnosis.

  • PDF

일차배양 간세포에서 t-Buty lhydroperoxide에 의해 유발된 산화적 스트레스에 대한 길경 열수 추출물의 보호효과 (Effects of Aqueous Extract Isolated from Platycodon grandiflorum Against t-Buty lhydroperoxide-induced Oxidative Stress in Rat Primary Hepatocytes)

  • 최철웅;이경진;정혜광
    • 약학회지
    • /
    • 제46권6호
    • /
    • pp.466-471
    • /
    • 2002
  • Oxidative stress is considered to be associated with many diseases, such as inflammatory and cardiovascular diseases, aging and cancer. An important etiological mechanism of these diseases may be a causal relationship between the presence of oxidants and the generation of lipid hydroperoxides derived from enzymatic reactions or xenobiotic metabolism. The hydroperoxides can be decomposed to alkoxy- (ROㆍ) and peroxy- (ROOㆍ) free radicals that can oxidize other cell components, resulting in changes in enzyme activity or the generation of mediators, which can cause further cell damage. The aim of this study was to evaluate the ability of aqueous extract from the roots of Platycodon grandiflorum A. DC (Campanulaceae), Changkil (CK), to affect cellular response in primary cultures of rat hepatocytes to t-butyl hydroperoxide (t-BHP) induced oxidative stress and hepatotoxicity. CK-treated cells showed an increased resistance to oxidative challenge, as revealed by a higher percent of survival capacity in respect to control cells. CK reduced t-BHP-enhanced lipid peroxidation measured as production of malondialdehyde and enhanced intracellular reduced glutathione depletion by t-BHP. Furthermore, CK protected from the t-BHP-induced intracellular generation of reactive oxygen species assessed by monitoring dichlorodihydrofluorescein fluorescence. It can be concluded that CK exerts an antioxidant action inside the cell, responsible for the observed modulation of the cellular response to oxidative challenge, and CK have a marked antioxidative and hepatoprotective potency.

환경성 발암 기전에서 유전자-환경 상호작용의 역할 (The Role of Gene-environment Interaction in Environmental Carcinogenesis)

  • 한소희;이경무
    • 한국환경보건학회지
    • /
    • 제36권1호
    • /
    • pp.1-13
    • /
    • 2010
  • Evidences supporting gene-environment interaction are accumulating in terms of environmental exposure including lifestyle factors and related genetic variants. One form of defense mechanism against cancer development involves a series of genes whose role is to metabolize (activation/detoxification) and excrete potentially toxic compounds and to repair subtle mistakes in DNA. The purpose of this article is to provide a brief review of the notion of gene-environment interaction, environmental/occupational carcinogens and related cancers, and previous studies of gene-environment interaction on cancers caused by exposure to carcinogenesis. With a number of studies on the interaction between lifestyle factors (e.g., smoking and diet) and genetic polymorphisms in genes involved in xenobiotic metabolism and DNA repair excluded, only several studies have been conducted on the interactive effects between polymorphisms of CYPs, GSTs, ERCCs, XRCCs and environmental/occupational carcinogens such as vinyl chloride, benzo[a]pyrene, and chloroform on carcinogenesis or genotoxicity. Future studies may need to be conducted with sufficient number of subjects and based on occupational cohorts to provide useful information in terms of advanced risk assessment and regulation of exposure level.

Metabolic profiling study of ketoprofen-induced toxicity using 1H NMR spectroscopy coupled with multivariate analysis

  • Jung, Jee-Youn;Hwang, Geum-Sook
    • 한국자기공명학회논문지
    • /
    • 제15권1호
    • /
    • pp.54-68
    • /
    • 2011
  • $^1H$ nuclear magnetic resonance (NMR) spectroscopy of biological samples has been proven to be an effective and nondestructive approach to probe drug toxicity within an organism. In this study, ketoprofen toxicity was investigated using $^1H$-NMR spectroscopy coupled with multivariate statistical analysis. Histopathologic test of ketoprofen-induced acute gastrointestinal damage in rats demonstrated a significant dose-dependent effect. Furthermore, principal component analysis (PCA) derived from $^1H$-NMR spectra of urinary samples showed clear separation between the vehicle-treated control and ketoprofen-treated groups. Moreover, PCA derived from endogenous metabolite concentrations through targeted profiling revealed a dose-dependent metabolic shift between the vehicle-treated control, low-dose ketoprofen-treated (10 mg/kg body weight), and high-dose ketoprofen-treated (50 mg/kg) groups coinciding with their gastric damage scores after ketoprofen administration. The resultant metabolic profiles demonstrated that the ketoprofen-induced gastric damage exhibited energy metabolism perturbations that increased urinary levels of citrate, cis-aconitate, succinate, and phosphocreatine. In addition, ketoprofen administration induced an enhancement of xenobiotic activity in fatty oxidation, which caused increase levels of N-isovalerylglycine, adipate, phenylacetylglycine, dimethylamine, betaine, hippurate, 3-indoxylsulfate, N,N-dimethylglycine, trimethyl-N-oxide, and glycine. These findings demonstrate that $^1H$-NMR-based urinary metabolic profiling can be used for noninvasive and rapid way to diagnose adverse drug effects and is suitable for explaining the possible biological pathways perturbed by nonsteroidal anti-inflammatory drug toxicity.

Free Radical Toxicology and Cancer Chemoprevention

  • Lin, Jen-Kun
    • Toxicological Research
    • /
    • 제17권
    • /
    • pp.83-88
    • /
    • 2001
  • Most reactive oxygen species (ROS) are free radicals and implicated in the development of a number of disease processes including artherosclerosis, neurodegenerative disorders, aging and cancer. ROS are byproducts of a number of in vivo metabolic processes and are formed deliberately as part of nor-mal inflammatory response. On the other hand, ROS are generated either as by products of oxygen reduction during xenobiotic metabolism or are liberated as the result of the futile redox cycling of the chemical agents including several chemical carcinogens. A better understanding of the mechanisms of free radical toxicity may yield valuable clue to risks associated with chemical exposures that leading to the development of chronic diseases including cancer. The molecular biology of ROS-mediated alterations in gene expression, signal transduction and carcinognesis is one of the important subjects in free radical toxicology. Epidemiological studies suggest that high intake of vegetables and fruits are associated with the low incidence of human cancer. Many phytopolyphenols such as tea polyphenols, curcumin, resveratrol, apigenin, genistein and other flavonoids have been shown to be cancer chemopreventive agents. Most of these compounds are strong antioxidant and ROS scavengers in vitro and effective inducers of antioxidant enzymes such as superoxide dismutatse, catalase and glutathione peroxidase in vivo. Several cellular transducers namely receptor tyrosine kinase, protein kinase C, MAPK, PI3K, c-jun, c-fos, c-myc, NFkB, IkB kinase, iNOS, COX-2, Bcl-2, Bax, etc have been shown to be actively modulated by phyto-polyphenols. Recent development in free radical toxicology have provided strong basis for understanding the action mechanisms of cancer chemoprevention.

  • PDF

GSTT1 Null Genotype Distribution in the Kumaun Region of Northern India

  • Bag, Arundhati;Upadhyay, Saloni;Jeena, Lalit M.;Pundir, Princi;Jyala, Narayan S.
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제14권1호
    • /
    • pp.87-89
    • /
    • 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.

일차 배양한 흰쥐의 간세포에서 사염화탄소로 인한 독성에 미치는 비테인의 효과 (Effects of Betaine on the $CCI_4$-Induced Toxicity in Primary Cultured Rat Hepatocytes)

  • 김선여;김홍표;이미경;김승희;문애리;한형미;허훈;김영중
    • 약학회지
    • /
    • 제37권5호
    • /
    • pp.499-503
    • /
    • 1993
  • Betaine, a major component of Lycii Fructus, was evaluated for its anti-hepatotoxic activity on carbon tetrachloride-induced hepatotoxicity in primary cultured rat hepatocytes. Betaine was found to attenuate carbon tetrachloride-induced hepatotoxicity both morphologically and biochemically. Typical hepatocyte necrosis due to carbon tetrachloride seemed to be reduced by 50 to 500 $\mu{M}$ of betaine under microscopical observation. The value of glutamic pyruvic transaminase released from the hepatocytes into the medium significantly decreased as betaine concentration increased. Betaine also significantly elevated the reduced activities of some enzymes, cytochrome P-450, 7-ethoxycoumarin-0-deethylase and glutathione-S-transferase, involved in xenobiotic metabolism due to carbon tetrachloride-induced hepatotoxicity. These results demonstrate a possible hepato-protective role of betaine against fatty liver that could be easily induced by carbon tetrachloride.

  • PDF

사염화탄소에 의하여 유발된 흰쥐의 간 독성에 미치는 비테인의 효과 (The Effect of Betaine on the $CCI_4$-Induced Hepatotoxicity in Rats)

  • 김선여;김홍표;이미경;변순정;김승희;문애리;한형미;허훈;김영중
    • 약학회지
    • /
    • 제37권5호
    • /
    • pp.538-543
    • /
    • 1993
  • Effects of betaine, a major component of Lycii Fructus, on carbon tetrachloride intoxicated rats were evaluated. Histological studies showed that betaine had improved the typical necrosis around centrilobular area in liver tissue due to the carbon tetrachloride intoxication. Betaine, whether it was administrated simultaneously or prior to carbon tetrachloride, prevented or retarded the elevation of liver-weight/body-weight ratio due to the carbon tetrachloride intoxication. Betaine also significantly elevated the reduced activities of some enzymes, cytochrome P-450, 7-ethoxycoumarin-0-deethylase and glutathione-S-transferase, involved in xenobiotic metabolism due to carbon tetrachloride intoxication. These results demonstrate a possible hepato-protective role of betaine against fatty liver that could be easily induced by carbon tetrachloride in rat.

  • PDF

Screening for the 3' UTR Polymorphism of the PXR Gene in South Indian Breast Cancer Patients and its Potential role in Pharmacogenomics

  • Revathidevi, Sundaramoorthy;Sudesh, Ravi;Vaishnavi, Varadharajan;Kaliyanasundaram, Muthukrishnan;MaryHelen, Kilyara George;Sukanya, Ganesan;Munirajan, Arasambattu Kannan
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제17권8호
    • /
    • pp.3971-3977
    • /
    • 2016
  • Background: Breast cancer, the commonest cancer among women in the world, ranks top in India with an incidence rate of 1,45,000 new cases and mortality rate of 70,000 women every year. Chemotherapy outcome for breast cancer is hampered due to poor response and irreversible dose-dependent cardiotoxicity which is determined by genetic variations in drug metabolizing enzymes and transporters. Pregnane X receptor (PXR), a member of the nuclear receptor superfamily, induces expression of drug metabolizing enzymes (DMEs) and transporters leading to regulation of xenobiotic metabolism. Materials and Methods: A genomic region spanning PXR 3' UTR was amplified and sequenced using genomic DNA isolated from 96 South Indian breast cancer patients. Genetic variants observed in our study subjects were queried in miRSNP to establish SNPs that alter miRNA binding sites in PXR 3' UTR. In addition, enrichment analysis was carried out to understand the network of miRNAs and PXR in drug metabolism using DIANA miRpath and miRwalk pathway prediction tools. Results: In this study, we identified SNPs rs3732359, rs3732360, rs1054190, rs1054191 and rs6438550 in the PXR 3; UTR region. The SNPs rs3732360, rs1054190 and rs1054191 were located in the binding site of miR-500a-3p, miR-532-3p and miR-374a-3p resulting in the altered PXR level due to the deregulation of post-transcriptional control and this leads to poor treatment response and toxicity. Conclusions: Genetic variants identified in PXR 3' UTR and their effects on PXR levels through post-transcriptional regulation provide a genetic basis for interindividual variability in treatment response and toxicity associated with chemotherapy.

The Exposure Status and Biomarkers of Polycyclic Aromatic Hydrocarbons in Shipyard Workers

  • Koh, Sang-Baek;Park, Jun-Ho;Yun, Ju-Song;Lee, Kang-Myoung;Cha, Bong-Suk;Chang, Sei-Jin;Kim, Cheong-Sik;Kim, Heon;Chang, Soung-Hoon
    • Molecular & Cellular Toxicology
    • /
    • 제2권2호
    • /
    • pp.134-140
    • /
    • 2006
  • Because shipyard workers are involved with various manufacturing process in shipyard industry, and they are exposed to many kinds of hazardous materials. Especially, painting workers were exposed polycyclic aromatic hydrocarbons (PAH). This study was conducted to assess the exposure status of PAH based on job-exposure matrix. We investigated the effect of genetic polymorphism of xenobiotic metabolism enzymes involved in PAH metabolism on levels of urinary metabolite. A total of 93 shipbuilding workers were recruited in this study. Questionnaire variables were age, sex, use of personal protective equipment, smoking, drinking, and work duration. The urinary metabolite was collected in the afternoon and corrected by urinary creatinine concentration. The genotypes of CYP1A1, CYP2E1, GSTM1, GSTT1 and UGT1A6 were investigated by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods with DNA extracted from venous blood. Urinary 1-OHP levels were significantly higher in direct exposured group (spray and touch-up) than indirect exposed group. Urinary 1-OHP, concentration of the high exposure with wild type of UGT1A6 was significantlyhigher than that of the high exposure with other UGT1A6 genotype. In multiple regression analysis of urinary 1-OHP, the regression coefficient of job grade was statistically significant (p<0.05) and UGT1A6 was not significant but a trend (p<0.1). The grade of exposure affected urinary PAH concentration was statistically significant. But genetic polymorphism of xenobiotics metabolism enzymes was not statistically significant. Further investigation of genetic polymorphism with large sample size is needed.