亚硒酸钠对肝细胞L-02端粒酶活性和端粒长度的作用  

Effects of Sodium Selenite on Telomerase Activity and Telomere Length

作　　者：刘琼[1] 王红[1] 胡德聪[1] 丁朝建[1] 肖恒[1] 徐辉碧[1] 舒柏华[2] 徐顺清[2] 

机构地区：[1]华中科技大学化学系,武汉430074 [2]同济医学院环境医学研究所,武汉430030

出　　处：《生物化学与生物物理学报》2003年第12期1117-1122,共6页

基　　金：国家自然科学基金资助项目 (No .3 0 170 90 3 );教育部优秀青年教师资助计划项目 ( 2 0 0 2;No .40 )~~

摘　　要：通过研究硒对端粒酶活性和端粒长度的作用 ,探讨硒抗衰老的生物学机制。实验以人肝细胞株L 0 2为研究对象 ,分别补充 0 .5和 2 .5 μmol L亚硒酸钠 ,采用端粒重复序列扩增 焦磷酸根酶联发光法、逆转录聚合酶链式反应法及流式荧光原位杂交法 ,分别检测细胞的端粒酶活性、人端粒酶逆转录酶催化亚基基因 (hTERT)的表达及端粒长度的变化。结果表明 :常规培养的肝细胞株L 0 2的端粒酶活性和hTERT基因表达水平均较低。补充 0 .5和2 .5 μmol L亚硒酸钠三周后细胞生长状况良好、端粒酶活性和hTERT基因表达水平显著性增高 ,且呈一定的剂量 效应关系。细胞补充亚硒酸钠四周后端粒长度显著增长。说明营养浓度的亚硒酸钠可通过提高端粒酶活性和增长端粒长度来减缓L 0 2肝细胞衰老、延长细胞寿命。To study the biological basis of selenium in resisting senescence through its effects on cellular telomerase activity and telomere length. In the experiments, the cell line of hepatocytes L-02 was divided into three groups supplemented with sodium selenite at final concentrations of 0, 0.5 and 2.5 μmol/L, respectively. Cellular telomerase activity was measured by telomeric repeat amplification protocol and enzymatic luminometric inorganic pyrophosphate detection assay. RT-PCR was used to semi-quantitatively detect human telomerase reverse transcriptase (hTERT) gene expression. The change of telomere length was assayed through flow cytometry and fluorescence in situ hybridization. Results showed that L-02 cells had low telomerase activity and hTERT gene expression level when cultured in the normal way. The cells grew well after 3-week-cultivation in the media supplemented with 0.5 or 2.5 μmol/L sodium selenite. Besides, sodium selenite significantly increased cellular telomerase activity and hTERT gene expression level. The telomere length of L-02 cells was also extended after 4-week-cultivation with sodium selenite. Thus, sodium selenite at nutritional doses could prolong the life span of hepatocytes L-02 through increasing telomerase activity and telomere length. This result provides a possible mechanism for explaining the anti-senescence function of selenium.

关 键 词：亚硒酸钠 肝细胞 端粒酶 活性 端粒长度 衰老 

分 类 号：R341[医药卫生—基础医学]