AKT2 deficiency alleviates doxorubicin-induced cardiac injury via alleviating oxidative stress in cardiomyocytes

Doxorubicin (DOX), a widely used chemotherapy agent in cancer treatment, encounters limitations in clinical efficacy due to associated cardiotoxicity. This study aims to explore the role of AKT serine/threonine kinase 2 (AKT2) in mitigating DOX-induced oxidative stress within the heart through both intracellular and extracellular signaling pathways. Utilizing Akt2 knockout (KO) and Nrf2 KO murine models, alongside neonatal rat cardiomyocytes (NRCMs), we systematically investigate the impact of AKT2 deficiency on DOX-induced cardiac injury. Our findings reveal that DOX administration induces significant oxidative stress, a primary contributor to cardiac injury. Importantly, Akt2 deficiency exhibits a protective effect by alleviating DOX-induced oxidative stress. Mechanistically, Akt2 deficiency facilitates nuclear translocation of NRF2, thereby suppressing intracellular oxidative stress by promoting the expression of antioxidant genes. Furthermore, We also observed that AKT2 inhibition facilitates superoxide dismutase 2 (SOD2) expression both inside macrophages and SOD2 secretion to the extracellular matrix, which is involved in lowering oxidative stress in cardiomyocytes upon DOX stimulation. The present study underscores the important role of AKT2 in mitigating DOX-induced oxidative stress through both intracellular and extracellular signaling pathways. Additionally, our findings propose promising therapeutic strategies for addressing DOX-induced cardiomyopathy in clinic.