title: MicroRNA-513a-5p mediates TNF-α and LPS induced apoptosis via downregulation of X-linked inhibitor of apoptotic protein in endothelial cells.
abstract: MicroRNAs (miRNAs) are endogenous non-coding small RNAs that have emerged as one of the central players of gene expression regulation. Endothelial cell apoptosis plays a fundamental role in the development of atherosclerosis. This study was designed to determine the effect of miR-513a-5p on apoptosis of human umbilical vein endothelial cells (HUVECs). HUVECs were treated with tumour necrosis factor-α (TNF-α) and lipopolysaccharide (LPS) and miR-513a-5p expression levels were determined. MiR-513a-5p target gene indentification, validation, and signalling pathways were investigated. Treatment of HUVECs with TNF-α and LPS up-regulated miR-513a-5p expressions more than 2-fold compared to control (P < 0.05). Inhibition of miR-513a-5p by antisense (AS) miR-513a-5p reversed TNF-α and LPS induced apoptosis (P < 0.01). Transfection of HUVECs with miR-513a-5p mimics also induced apoptosis (P < 0.01). Treatment of HUVECs with TNF-α and LPS attenuated X-linked inhibitor of apoptosis (XIAP) while increased caspase-3 expression, poly ADP-ribose polymerase (PARP) cleavage, and p53 expression. These effects were reversed by inhibition of miR-513a-5p. Of those miR-513a-5p candidate target genes, we identified and validated XIAP as a miR-513a-5p target gene. Targeting of the XIAP 3'-untranslated region by miR-513a-5p using luciferase reporter assay resulted in attenuated luciferase activity. Transfection of HUVECs with AS miR-513a-5p increased XIAP protein expression while miR-513a-5p mimics attenuated XIAP expression. These results together suggest that miR-513a-5p mediates TNF-α and LPS induced apoptosis via downregulation of XIAP in HUVECs.
authors.affiliation: Department of Obstetrics and Gynecology, School of Medicine, Keimyung University, Daegu 700-712, Republic of Korea.
authors.forename: Sojin
authors.initials: S
authors.lastname: Shin
authors.forename: Kyo Chul
authors.initials: KC
authors.lastname: Moon
authors.forename: Keon Uk
authors.initials: KU
authors.lastname: Park
authors.forename: Eunyoung
authors.initials: E
authors.lastname: Ha
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D015536:Down-Regulation / Q000187:drug effects; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D008070:Lipopolysaccharides / Q000494:pharmacology*; D035683:MicroRNAs / Q000502:physiology*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D051636:X-Linked Inhibitor of Apoptosis Protein / Q000235:genetics*
chemical_list: D008070:Lipopolysaccharides; C546275:MIRN513A1 microRNA, human; D035683:MicroRNAs; D014409:Tumor Necrosis Factor-alpha; D051636:X-Linked Inhibitor of Apoptosis Protein