Isoliensinine Ameliorates Pathological Cardiac Hypertrophy After Aerobic Exercise by Activating Cytochrome c Oxidase Subunit 6A2

Pathological cardiac hypertrophy is an abnormal remodeling process of the heart under chronic pressure overload, characterized by myocardial fibrosis, apoptosis, and progressive decline in cardiac function, ultimately leading to heart failure or death. Although aerobic exercise, particularly swimming, has been shown to alleviate pathological cardiac hypertrophy, its molecular mechanisms remain incompletely understood. In this study, metabolomic and transcriptomic analyses revealed the molecular mechanisms underlying swimming-induced improvement of pathological cardiac hypertrophy. Results showed that swimming training significantly altered the level of isoliensinine in animals. Further studies demonstrated that isoliensinine exerts cardioprotective effects by regulating the expression of Cytochrome C Oxidase Subunit 6A2 (COX6A2), establishing for the first time the critical role of the Isoliensinine-COX6A2 signaling axis in cardiac function regulation. To validate this axis, a pathological cardiac hypertrophy model was constructed in mice through transverse aortic constriction (TAC). Both swimming training and isoliensinine intervention significantly improved cardiac structure and function. In vitro experiments using isoproterenol (ISO)-induced hypertrophy in H9C2 cells further confirmed the essential role of this signaling axis in suppressing pathological hypertrophy and maintaining mitochondrial homeostasis. Our findings demonstrate that swimming mitigates pathological cardiac hypertrophy by enhancing COX6A2 expression by isoliensinine, thereby improving mitochondrial function. This study not only expands the understanding of exercise-mediated mechanisms in pathological cardiac remodeling but also highlights the cardioprotective potential of isoliensinine and COX6A2 as therapeutic targets for preventing and treating heart failure.