title: Involvement of MicroRNAs in hydrogen peroxide-mediated gene regulation and cellular injury response in vascular smooth muscle cells.
abstract: MicroRNAs (miRNAs) comprise a novel class of endogenous, small, noncoding RNAs that negatively regulate approximately 30% of genes in a cell via degradation or translational inhibition of their target mRNAs. However, the effects of reactive oxygen species (ROS) on miRNA expression and the roles of miRNAs in ROS-mediated gene regulation and biological functions of vascular cells are unclear. Using microarray analysis, we demonstrated that miRNAs are aberrantly expressed in vascular smooth muscle cells (VSMCs) after treatment with hydrogen peroxide (H(2)O(2)). H(2)O(2)-mediated up-regulation of microRNA-21 (miR-21) was further confirmed by quantitative real-time PCR. To determine the potential roles of miRNAs in H(2)O(2)-mediated gene regulation and cellular effects, miR-21 expression was down-regulated by miR-21 inhibitor and up-regulated by pre-miR-21. H(2)O(2)-induced VSMC apoptosis and death were increased by miR-21 inhibitor and decreased by pre-miR-21. Programmed cell death 4(PDCD4) was a direct target of miR-21 that was involved in miR-21-mediated effects on VSMCs. Pre-miR-21-mediated protective effect on VSMC apoptosis and death was blocked via adenovirus-mediated overexpression of PDCD4 without the miR-21 binding site. Moreover, activator protein 1 was a downstream signaling molecule of PDCD4 in miR-21-modulated VSMCs. The results suggest that miRNAs in VSMCs are sensitive to H(2)O(2) stimulation. miRN-21 participates in H(2)O(2)-mediated gene regulation and cellular injury response through PDCD4 and the activator protein 1 pathway. miRNAs might play a role in vascular diseases related to ROS.
authors.affiliation: RNA and Cardiovascular Research Laboratory, Department of Anesthesiology, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, New Jersey 07101, USA.
authors.forename: Ying
authors.initials: Y
authors.lastname: Lin
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Liu
authors.forename: Yunhui
authors.initials: Y
authors.lastname: Cheng
authors.forename: Jian
authors.initials: J
authors.lastname: Yang
authors.forename: Yuqing
authors.initials: Y
authors.lastname: Huo
authors.forename: Chunxiang
authors.initials: C
authors.lastname: Zhang
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects*; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D008297:Male; D035683:MicroRNAs / Q000378:metabolism*; D009131:Muscle, Smooth, Vascular / Q000293:injuries / Q000378:metabolism* / Q000473:pathology; D032389:Myocytes, Smooth Muscle / Q000378:metabolism* / Q000473:pathology; D020411:Oligonucleotide Array Sequence Analysis; D016877:Oxidants / Q000494:pharmacology*; D012322:RNA Precursors / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D018808:Transcription Factor AP-1 / Q000378:metabolism; D014652:Vascular Diseases / Q000378:metabolism* / Q000473:pathology
chemical_list: D051017:Apoptosis Regulatory Proteins; D035683:MicroRNAs; D016877:Oxidants; C467042:Pdcd4 protein, rat; D012322:RNA Precursors; D018808:Transcription Factor AP-1; D006861:Hydrogen Peroxide