title: [Effects of sodium selenite on telomerase activity and telomere length].
abstract: 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 micromol/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 micromol/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.
authors.affiliation: Department of Chemistry, Huazhong University of Science and Technology, Wuhan 430074, China. qiongliu_hust@163.net
authors.forename: Qiong
authors.initials: Q
authors.lastname: Liu
authors.forename: Hong
authors.initials: H
authors.lastname: Wang
authors.forename: De-Cong
authors.initials: DC
authors.lastname: Hu
authors.forename: Chao-Jian
authors.initials: CJ
authors.lastname: Ding
authors.forename: Heng
authors.initials: H
authors.lastname: Xiao
authors.forename: Hui-Bi
authors.initials: HB
authors.lastname: Xu
authors.forename: Bai-Hua
authors.initials: BH
authors.lastname: Shu
authors.forename: Shun-Qing
authors.initials: SQ
authors.lastname: Xu
mesh_terms: D002460:Cell Line; D004268:DNA-Binding Proteins; D004305:Dose-Response Relationship, Drug; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D022781:Hepatocytes / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018038:Sodium Selenite / Q000494:pharmacology*; D019098:Telomerase / Q000235:genetics* / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; D012333:RNA, Messenger; D019098:Telomerase; D018038:Sodium Selenite