MiR-26a-5p alleviates cardiac hypertrophy and dysfunction via targeting ADAM17.

Cardiac hypertrophy has been a high prevalence rate throughout the world. It has posed a big threat to public health due to limited therapeutic approaches. Previous studies showed that pathological cardiac hypertrophy was associated with autophagy, microRNAs (miRNA), and other signaling pathways, while the molecular mechanisms remain incompletely characterized. In this study, we used thoracic aortic constriction (TAC)-induced mice and angiotensin-II (Ang-II)-induced H9C2 cell line as cardiac hypertrophy model to investigate the role of miR-26a-5p in cardiac hypertrophy. We found that miR-26a-5p was downregulated in cardiac hypertrophy mice. Overexpression of miR-26a-5p by type 9 recombinant adeno-associated virus (rAAV9) reversed the heart hypertrophic manifestations. The phenotypes were also promoted by miR-26a-5p inhibitor in Ang-II-induced H9C2 cells. Through miRNA profile analysis and dual-luciferase reporter assay, ADAM17 was identified as a direct target of miR-26a-5p. Restored expression of ADAM17 disrupted the effect of miR-26a-5p on cardiac hypertrophy. To sum up, these results indicated that miR-26a-5p played an inhibitory role in cardiac hypertrophy and dysfunction via targeting ADAM17. The miR-26a-5p-ADAM17-cardiac hypertrophy axis provided special insight and a new molecular mechanism for a better understanding of cardiac hypertrophy disease, as well as the diagnostic and therapeutic practice.