Telomerase Activity and Telomerase Reverse Transcriptase Expression Induced by Selenium in Rat Hepatocytes  

作　　者：RI-AN YU HUA-JIE CHEN LING-FEI HE BING CHEN XUE-MIN CHEN 

机构地区：[1]Department of Occupational and Environmental Health, School of Public Health, Guangdong Pharmaceutical University, Guangzhou 510310, Guangdong, China [2]Department of Occupational and Environmental Health, MOE Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China [3]Department of Dental Medicine, The First Affiliated Hospital of Guangdong Pharmaceutical University, Guangzhou 510080, Guangdong, China

出　　处：《Biomedical and Environmental Sciences》2009年第4期311-317,共7页生物医学与环境科学（英文版）

基　　金：supported by the Scientific Foundation and Teacher’s Foundation of Guangdong Pharmaceutical University (No.2006GGW01);the National Natural Science Foundation of China (No.30271110)

摘　　要：Objective To investigate the effects of sodium selenite on telomerase activity, apoptosis and expression of TERT, c-myc and p53 in rat hepatocytes. Methods Selenium at doses of 2.5, 5.0, and 10 μmol/kg was given to SD rats by garage. In rat hepatocytes, telomerase activity was measured by the telomeric repeat amplification protocol （TRAP）, apoptosis was detected by flow cytometry, and expressions of telomerase reverse transcriptase （TERT）, c-myc and p53 were analyzed by reverse transcription-polymerase chain reaction （RT-PCR）. c-Myc and P53 proteins were detected by immunochemistry. Results Selenium at doses of 2.5, 5.0, and 10 μmol/kg significantly increased hepatocellular telomerase activity and induced apoptosis in a dose-dependent manner. Although selenium at doses of 2.5, 5.0, and 10 μmol/kg displayed no obvious enhancing effect on the TERT mRNA expression in rat hepatocytes （P〉0.05）, it significantly increased the c-myc mRNA and p53 mRNA expression at the dose of 10 μmol/kg （P〈0.05）. Selenium at doses of 5.0 and 10 μmol/kg obviously increased the content of P53 protein in rat hepatocytes, but only at the dose of 10 μmol/kg, it significantly promoted the value of c-Myc protein in them. Conclusion Selenium can slightly increase telomerase activity and TERT expression, and significantly induce apoptosis and over-expression of c-myc and p53 at relatively high doses. The beneficial effects of selenium on senescence and aging may be mediated by telomerase activation and expression of TERT, c-myc, and p53 in rat hepatocytes.Objective To investigate the effects of sodium selenite on telomerase activity, apoptosis and expression of TERT, c-myc and p53 in rat hepatocytes. Methods Selenium at doses of 2.5, 5.0, and 10 μmol/kg was given to SD rats by garage. In rat hepatocytes, telomerase activity was measured by the telomeric repeat amplification protocol （TRAP）, apoptosis was detected by flow cytometry, and expressions of telomerase reverse transcriptase （TERT）, c-myc and p53 were analyzed by reverse transcription-polymerase chain reaction （RT-PCR）. c-Myc and P53 proteins were detected by immunochemistry. Results Selenium at doses of 2.5, 5.0, and 10 μmol/kg significantly increased hepatocellular telomerase activity and induced apoptosis in a dose-dependent manner. Although selenium at doses of 2.5, 5.0, and 10 μmol/kg displayed no obvious enhancing effect on the TERT mRNA expression in rat hepatocytes （P〉0.05）, it significantly increased the c-myc mRNA and p53 mRNA expression at the dose of 10 μmol/kg （P〈0.05）. Selenium at doses of 5.0 and 10 μmol/kg obviously increased the content of P53 protein in rat hepatocytes, but only at the dose of 10 μmol/kg, it significantly promoted the value of c-Myc protein in them. Conclusion Selenium can slightly increase telomerase activity and TERT expression, and significantly induce apoptosis and over-expression of c-myc and p53 at relatively high doses. The beneficial effects of selenium on senescence and aging may be mediated by telomerase activation and expression of TERT, c-myc, and p53 in rat hepatocytes.

关 键 词：SELENIUM TELOMERASE Telomerase reverse transcriptase C-MYC P53 

分 类 号：R37[医药卫生—病原生物学]