GDF11 alleviates pathological myocardial remodeling in diabetic cardiomyopathy through SIRT1-dependent regulation of oxidative stress and apoptosis

Abstract Background Diabetic cardiomyopathy (DCM) is characterized by cardiac dysfunction and cardiomyocyte injury, which induced by metabolic disorder. Nowadays, there is still a lack of drugs for the treatment of DCM. Growth differentiation factor 11 (GDF11) is a novel member of the transforming growth factor β superfamily that alleviates cardiac hypertrophy, myocardial infarction, and vascular injury by regulating oxidative stress, inflammation, and cell survival. However, the roles and underlying mechanisms of GDF11 in DCM remain largely unknown. Methods In this study, we sought to determine whether GDF11 could prevent DCM. The mouse model of diabetes was established by administering a high-fat diet and intraperitoneal injecting streptozotocin. After that, intramyocardial injection of an adeno-associated virus carrying GDF11 gene was used to achieve myocardium-specific overexpression. Results Our data showed that GDF11 overexpression remarkably improved cardiac dysfunction and interstitial fibrosis by reducing the levels of reactive oxygen species and protecting against cardiomyocyte loss. Mechanistically, decreased sirtuin 1 (SIRT1) expression was observed in diabetic mice, which was significantly increased after GDF11 overexpression. To further explore how SIRT1 mediates the role of GDF11, the selective inhibitor EX527 was used to block SIRT1 signaling pathway, which abolished the protective effects of GDF11 against DCM. In vitro studies confirmed that GDF11 protected against H9c2 cell injury in high glucose and palmitate by attenuating oxidative injury and apoptosis, and these effects were also eliminated by SIRT1 depletion. Conclusion Our results demonstrated for the first time that GDF11 protected against DCM by regulating SIRT1 signaling pathway, and GDF11 had the potential to become a novel target for reversing cardiac dysfunction in diabetic patients.