LncRNA SENCR overexpression attenuated the proliferation, migration and phenotypic switching of vascular smooth muscle cells in aortic dissection via the miR-206/myocardin axis

Abstract

Background and aims: Smooth muscle and endothelial cell-enriched migration/differentiation-associated lncRNA (SENCR) has been reported to be associated with some cardiovascular diseases; however, its function and exact molecular mechanism in aortic dissection (AD) remain undefined. Thus, we investigated the effects of SENCR on AD and its potential mechanisms.

Methods and results: SENCR expression in aortic media specimens from AD patients was detected by quantitative real-time PCR (qPCR). The roles of SENCR in vascular smooth muscle cell (VMSC) proliferation and migration as well as in the regulation of contractile phenotype genes were studied using CCK-8, wound healing, Transwell, qPCR and Western blot assays. Dual-luciferase reporter assays were performed to identify the regulatory correlation between SENCR, miR-206 and myocardin. Furthermore, mouse AD models were constructed with ApoE^-/- mice, and the effect of upregulated SENCR on phenotypic switching in the AD model was detected using hematoxylin and eosin (H&E) staining and immunohistochemistry (IHC) assays. SENCR overexpression inhibited VSMC proliferation, migration and synthetic phenotype-related gene expression; decreased miR-206 expression; increased myocardin expression; and suppressed rupture of the aortic media in mice. SENCR knockdown had the opposite effects. Our results further suggested that miR-206 upregulation could reverse the inhibitory roles of SENCR upregulation and that myocardin upregulation could restore the function of SENCR upregulation in VSMCs. Dual-luciferase reporter assays confirmed that SENCR regulated miR-206, which directly targeted myocardin in VSMCs.

Conclusion: SENCR overexpression suppressed VMSC proliferation and migration, maintained the contractile phenotype and suppressed aortic dilatation via the miR-206/myocardin axis.

Keywords: Aortic dissection; Migration; Myocardin; Phenotypic switching; Proliferation; SENCR; Vascular smooth muscle cells; miR-206.