Knockdown of mechanosensitive miRNA cluster—miR‐106b~25 decreases endothelial proliferation and prevents atherosclerosis in ApoE −/− mice

Atherosclerosis is the underlying cause of cardiovascular events, such as heart attack and stroke. The disease preferentially occurs in arterial regions exposed to disturbed flow (d-flow), in part, due to alterations in endothelial gene expression. Emerging evidence indicates that alteration of flow conditions regulate expression of small, noncoding RNAs (miRNAs) in endothelial cells. Here, using a partial carotid ligation model of d-flow induced atherosclerosis, we identified a highly conserved, flow-sensitive miRNA cluster, miR-106b-93-25, that is upregulated in the carotid endothelium that experienced d-flow for 48 hours. Additional studies using endothelial-enriched RNAs from the lesser- (chronic d-flow region) and greater curvature (chronic s-flow region) of aortic arch further validate the increased expression of 106b-93-25 in the chronic d-flow regions. Using arterial endothelial cells from human and mouse and a cone-and-plate shear device, we found that expression of miR-106b-93-25 increases in the endothelial cells exposed to oscillatory shear stress (OS) for 24 h. In silico and subsequent wet-lab target identification studies showed that this miRNA cluster targets the inhibitors of cell cycle regulators, cyclin-dependent kinase inhibitors (CDKIs). Studies including gain-of-function (pre-miR-106b, -93 and -25) and loss-of-function (anti-miR-106b, -93 and -25) approaches showed that this miRNA cluster downregulates the CDKN1A and CDKN1B in a flow-dependent manner. Using our mouse partial carotid ligation model of d-flow induced atherosclerosis, we demonstrated that genetic knockdown of mechanosensitive miRNA cluster—miR-106b~25 using heterozygous miR-106b~25+/− mice on ApoE background prevents atherosclerosis development in comparison to the age-matched littermate controls. Our results suggest that targeting mechanosensitive miRNA cluster using anti-miRNA-based approaches may provide a new treatment strategy for atherosclerosis. Support or Funding Information SK received an American Heart Association postdoctoral award to carry out the research work. Knockdown of miR-106b-93-25 in ApoE KO mice inhibits atherosclerosis development in partial carotid ligation model of atherosclerosis Knockdown of miR-106b-93-25 in ApoE KO mice inhibits atherosclerosis development in partial carotid ligation model of atherosclerosis