Purpose of review: Control of vascular smooth muscle cell (VSMC) phenotype is essential in the development and maintenance of a healthy vasculature. Acquisition of a synthetic, proproliferative phenotype by VSMCs following vascular insult is central to neointimal formation and the development of vascular pathology. MicroRNAs (miRNAs) are relatively recently discovered negative regulators of gene expression and act at the post-transcriptional level. MiRNAs have the potential to control VSMC phenotype. In this review, we discuss the recent findings on how miRNAs influence VSMC biology and acute vascular pathology.
Recent findings: MiRNAs play an important role in the gene regulation by growth factors and downstream transcription factors involved in VSMC phenotypic control and deregulation. Recent studies have revealed miRNAs that are involved in VSMC regulation and further identified several target genes which are implicated in VSMC pathobiology, highlighting new disease mechanisms. Paracrine miRNA-regulated crosstalk between endothelial and VSMCs has also been demonstrated, revealing a novel mechanism through which vascular cells communicate in health and disease.
Summary: MiRNAs appear to play a major role in the capability of VSMCs to phenotypically switch from a contractile to a synthetic state. Altering miRNA expression levels can prevent and even reverse the acquisition of VSMC synthetic phenotype in vivo and reduce neointimal formation, thereby implicating miRNAs as exciting future therapeutic targets for vascular proliferative disease.