Abstract
DNA damage induced by oxidative stress during cardiac hypertrophy activates the ataxia telangiectasia mutated (ATM)-mediated DNA damage response (DDR) signaling, in turn aggravating the pathological cardiomyocyte growth. This study aims to identify the functional associations of long noncoding RNA (lncRNAs) with cardiac hypertrophy and DDR. The altered ventricular lncRNAs in the mice between sham and transverse aortic constriction (TAC) group were identified by microarray analysis, and a novel lncRNA AK144717 was found to gradually upregulate during the development of pathological cardiac hypertrophy induced by TAC surgery or angiotensin II (Ang II) stimulation. Silencing AK144717 had a similar anti-hypertrophic effect to that of ATM inhibitor KU55933 and also suppressed the activated ATM-DDR signaling induced by hypertrophic stimuli. The involvement of AK144717 in DDR and cardiac hypertrophy was closely related to its interaction with HMGB1, as silencing HMGB1 abolished the effects of AK144717 knockdown. The binding of AK144717 to HMGB1 prevented the interaction between HMGB1 and SIRT1, contributing to the increased acetylation and then cytosolic translocation of HMGB1. Overall, our study highlights the role of AK144717 in the hypertrophic response by interacting with HMGB1 and regulating DDR, hinting that AK144717 is a promising therapeutic target for pathological cardiac growth.