title: A regulatory circuit involving miR-143 and DNMT3a mediates vascular smooth muscle cell proliferation induced by homocysteine.
abstract: Accumulating evidence has suggested that homocysteine (Hcy) is an independent risk factor for atherosclerosis (AS). Hcy can promote vascular smooth muscle cell (VSMC) proliferation, which is pivotal in the pathogenesis and progression of AS. The aim of the present study was to investigate the epigenetic regulatory mechanism of microRNA (miR)‑143‑mediated VSMCs proliferation induced by Hcy. The results of a 3‑(4,5‑dimethylthiazol‑2‑yl)‑2,5‑diphe‑nyltetrazolium bromide assay revealed that VSMC proliferation was increased by 1.39‑fold following treatment with 100 mM Hcy, compared with the control group. The levels of miR‑143 were markedly downregulated in the Hcy group, compared with the control group, as determined using reverse transcription‑quantitative polymerase chain reaction analysis. In addition, the level of miR‑143 methylation was increased markedly in the VSMCs treated with Hcy, compared with the control, and was reduced following transfection with DNA methyltransferase (DNMT)3a small interfering RNA, determined using methylation‑specific‑PCR. The activities of DNMT3a luciferase were also altered accordingly in VSMCs transfected with pre‑miR‑143 and miR‑143 inhibitor, respectively. In addition, the expression of miR‑143 was observed to be inversely correlated with the mRNA and protein expression of DNMT3 in the VSMCs. Taken together, these findings suggest that DNMT3a is a direct target of miR‑143, and that the upregulation of DNMT3 is responsible for the hypermethylation of miR‑143 in Hcy-induced VSMC proliferation.
authors.affiliation: Department of Prenatal Diagnosis Center, General Hospital of Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region 750004, P.R. China.
authors.forename: Hui-Ping
authors.initials: HP
authors.lastname: Zhang
authors.affiliation: Department of Prenatal Diagnosis Center, General Hospital of Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region 750004, P.R. China.
authors.forename: Yan-Hua
authors.initials: YH
authors.lastname: Wang
authors.affiliation: College of Basic and Forensic Medicine, Sichuan University, Chengdu 610041, P.R. China.
authors.forename: Cheng-Jian
authors.initials: CJ
authors.lastname: Cao
authors.affiliation: Department of Pathophysiology, Basic Medical School, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region 750004, P.R. China.
authors.forename: Xiao-Ming
authors.initials: XM
authors.lastname: Yang
authors.affiliation: Department of Physiology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu 610041, P.R. China.
authors.forename: Sheng-Chao
authors.initials: SC
authors.lastname: Ma
authors.affiliation: Department of Laboratory Medicine, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous, Region 750004, P.R. China.
authors.forename: Xue-Bo
authors.initials: XB
authors.lastname: Han
authors.affiliation: Department of Pathophysiology, Basic Medical School, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region 750004, P.R. China.
authors.forename: Xiao-Ling
authors.initials: XL
authors.lastname: Yang
authors.affiliation: College of Basic and Forensic Medicine, Sichuan University, Chengdu 610041, P.R. China.
authors.forename: An-Ning
authors.initials: AN
authors.lastname: Yang
authors.affiliation: Department of Pathophysiology, Basic Medical School, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region 750004, P.R. China.
authors.forename: Jue
authors.initials: J
authors.lastname: Tian
authors.affiliation: Department of Pathophysiology, Basic Medical School, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region 750004, P.R. China.
authors.forename: Hua
authors.initials: H
authors.lastname: Xu
authors.affiliation: Department of Pathophysiology, Basic Medical School, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region 750004, P.R. China.
authors.forename: Ming-Hao
authors.initials: MH
authors.lastname: Zhang
authors.affiliation: Department of Pathophysiology, Basic Medical School, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region 750004, P.R. China.
authors.forename: Yi-Deng
authors.initials: YD
authors.lastname: Jiang
mesh_terms: D049109:Cell Proliferation / Q000187:drug effects; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000378:metabolism*; D019175:DNA Methylation / Q000187:drug effects / Q000235:genetics; D000090205:DNA Methyltransferase 3A; D015536:Down-Regulation / Q000187:drug effects; D053263:Gene Regulatory Networks / Q000187:drug effects; D006710:Homocysteine / Q000494:pharmacology*; D006801:Humans; D035683:MicroRNAs / Q000378:metabolism*; D009131:Muscle, Smooth, Vascular / Q000166:cytology*; D032389:Myocytes, Smooth Muscle / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology*; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic / Q000235:genetics; D015854:Up-Regulation / Q000187:drug effects
chemical_list: C000717967:DNMT3A protein, human; C542359:MIRN143 microRNA, human; D035683:MicroRNAs; D006710:Homocysteine; D004248:DNA (Cytosine-5-)-Methyltransferases; D000090205:DNA Methyltransferase 3A