Protective effect of secretory APE1/Ref‐1 on doxorubicin‐induced cardiotoxicity via suppression of ROS and p53 pathway

Abstract Aims The clinical application of doxorubicin (DOX), a potent anthracycline anticancer drug that effectively treats various malignancies, is limited by its side effects, such as cardiomyopathy. Apurinic/apyrimidinic endonuclease 1/redox factor‐1 (APE1/Ref‐1) is a multifunctional protein that can be secreted and is a promising target for the reduction of DOX‐induced inflammation and oxidative stress. We aimed to investigate the protective role of secretory APE1/Ref‐1 against DOX‐induced cardiac injury. Methods and results Designated adenoviral preprotrypsin‐leading sequence APE1/Ref‐1 (Ad‐PPTLS‐APE1/Ref‐1) was used to overexpress secretory APE1/Ref‐1 and assess its role in preventing DOX‐induced cardiomyopathy in vitro. Our findings revealed that exposure to secretory APE1/Ref‐1 significantly decreased N‐terminal pro‐B‐type natriuretic peptide levels in DOX‐treated H9C2 cells. In addition, secretory APE1/Ref‐1 reduced the severity of cardiomyocyte injury and apoptosis in both in vitro and in vivo DOX‐induced cardiotoxicity models. The observed cardioprotective effects of secretory APE1/Ref‐1 were mediated via inhibition of the p53 signalling pathway and enhancement of cell viability through attenuation of oxidative stress in DOX‐treated cardiomyocytes. Conclusions Our study provides evidence that secretory APE1/Ref‐1 has the potential to inhibit DOX‐induced cardiac toxicity by inhibiting oxidative stress and p53 related apoptosis both in vitro and in vivo. These findings suggest that secretory APE1/Ref‐1 supplementation is a promising strategy to attenuate DOX‐induced cardiomyocyte damage in a preclinical model. Further clinical investigations are essential to validate the therapeutic efficacy and safety of the intervention in human subjects.