Super-enhancers and Mef2c: Novel regulators of cardiac hypertrophy via the Hey2/Notch/p38 signaling pathway.

Cardiac hypertrophy (CH), a pathological response to stress, is intricately regulated by the dynamic control of gene expression. This study explored the role of super-enhancers (SEs) and the transcription factor Mef2c in CH regulation. Using a transverse aortic constriction (TAC) mouse model, we demonstrated that inhibition of SEs with JQ-1, a BET inhibitor, significantly attenuated hypertrophic responses, as evidenced by reduced heart weight indices, enhanced cardiac function, and decreased expression of hypertrophic marker proteins BNP and β-MHC. Further analysis revealed that Mef2c, a key transcription factor, is driven by SEs in CH. In vivo and in vitro overexpression of Mef2c promotes CH, while deletion of the Mef2c SE region alleviates this condition. Mechanistically, we identified Hey2 as a downstream target of Mef2c and demonstrated that Mef2c regulates CH through the Hey2/Notch/p38 signaling pathway. Our findings provide novel insights into the molecular mechanisms underlying CH and suggest potential therapeutic targets for its treatment.