LncRNA NEAT1 sponges miR-214-3p to promote osteoblast differentiation through regulating the PI3K/AKT/mTOR pathway in aortic valve calcification
Rongjian Xu, Yuhui Sun, Fangfei Tian, Min Zhao
Abstract
Calcific aortic valve disease (CAVD) is the common valvular disease associated with significant morbidity and mortality. Dysregulation of long non-coding RNA (lncRNA) has been implicated in the pathogenesis of CAVD. This study aims to investigate the role of NEAT1 in CAVD pathogenesis. NEAT1, miR-214-3p and mRNA expressions were determined by qRT-PCR. Protein expressions were detected by Western blotting. Mineralized bone matrix formation was assessed by Alizarin Red staining. The osteogenic phenotype was evaluated by the alkaline phosphatase activity assay. Dual-luciferase assays were employed to confirm the binding interactions between NEAT1 and miR-214-3p, miR-214-3p and PTEN. NEAT1 was up-regulated in calcific aortic valves and after osteogenic induction of valve interstitial cells (VICs). NEAT1 could act as a positive regulator of osteogenic differentiation by repressing miR-214-3p and thereby promote expression of osteoblast-specific markers. Mechanistically, we identified PTEN as a direct target of miR-214-3p. PTEN could regulate the PI3K/AKT/mTOR pathway and participate in osteogenic differentiation. Importantly, NEAT1 could directly interact with miR-214-3p and change of miR-214-3p expression could efficiently reverse PTEN expression and osteogenic differentiation induced by NEAT1. Thus, NEAT1 positively regulated PTEN expression and activated autophagy through sponging miR-214-3p, and promoted osteogenic differentiation through the PI3K/AKT/mTOR pathway. In conclusion, we elucidates the vital function of NEAT1 as a miRNA sponge in CAVD pathogenesis, and sheds new light on lncRNA-directed diagnostic and therapeutic strategies for CAVD.