Involvement of MicroRNAs in hydrogen peroxide-mediated gene regulation and cellular injury response in vascular smooth muscle cells

Ying Lin, Xiaojun Liu, Yunhui Cheng, Jian Yang, Yuqing Huo, Chunxiang Zhang

Research output: Contribution to journalArticle

174 Scopus citations


MicroRNAs (miRNAs) comprise a novel class of endogenous, small, noncoding RNAs that negatively regulate ∼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 (H2O2). H2O2-mediated up-regulation of microRNA-21 (miR-21) was further confirmed by quantitative real-time PCR. To determine the potential roles of miRNAs in H2O2-mediated gene regulation and cellular effects, miR-21 expression was down-regulated by miR-21 inhibitor and up-regulated by pre-miR-21. H2O2-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 H2O2 stimulation. miRN-21 participates in H2O2-mediated gene regulation and cellular injury response through PDCD4 and the activator protein 1 pathway. miRNA might play a role in vascular diseases related to ROS.

Original languageEnglish (US)
Pages (from-to)7903-7913
Number of pages11
JournalJournal of Biological Chemistry
Issue number12
StatePublished - Mar 20 2009


ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

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