title: MicroRNA-34a regulation of endothelial senescence.
abstract: Endothelial senescence is thought to play a role in cardiovascular diseases such as atherosclerosis. We hypothesized that endothelial microRNAs (miRNAs) regulate endothelial survival and senescence. We found that miR-34a is highly expressed in primary endothelial cells. We observed that miR-34a expression increases in senescent human umbilical cord vein endothelial cells (HUVEC) and in heart and spleen of older mice. MiR-34a over-expression induces endothelial cell senescence and also suppresses cell proliferation by inhibiting cell cycle progression. Searching for how miR-34a affects senescence, we discovered that SIRT1 is a target of miR-34a. Over-expressing miR-34a inhibits SIRT1 protein expression, and knocking down miR-34a enhances SIRT1 expression. MiR-34a triggers endothelial senescence in part through SIRT1, since forced expression of SIRT1 blocks the ability of miR-34a to induce senescence. Our data suggest that miR-34a contributes to endothelial senescence through suppression of SIRT1.
authors.affiliation: Department of Medicine, Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, West Henrietta, NY 14586, USA.
authors.forename: Takashi
authors.initials: T
authors.lastname: Ito
authors.forename: Shusuke
authors.initials: S
authors.lastname: Yagi
authors.forename: Munekazu
authors.initials: M
authors.lastname: Yamakuchi
mesh_terms: D000818:Animals; D002453:Cell Cycle / Q000235:genetics; D002478:Cells, Cultured; D016922:Cellular Senescence / Q000235:genetics*; D004730:Endothelium, Vascular / Q000502:physiology*; D005786:Gene Expression Regulation; D006801:Humans; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D009206:Myocardium / Q000166:cytology / Q000378:metabolism; D056564:Sirtuin 1 / Q000235:genetics*; D013154:Spleen / Q000166:cytology / Q000378:metabolism
chemical_list: C522425:MIRN34 microRNA, human; C551848:MIRN34a microRNA, mouse; D035683:MicroRNAs; C447939:SIRT1 protein, human; D056564:Sirtuin 1