Didymin attenuates doxorubicin-induced cardiotoxicity by inhibiting oxidative stress

Objective: This study was designed to investigate the protective effects of didymin (Did) on doxorubicin (DOX)-induced cardiotoxicity. Methods: After pretreatment with Did (2, 4, 8 mg/kg intraperitoneal i.p.) for 7 d, the male C57 mice were injected with single dose of DOX (20 mg/kg i.p.). The cardioprotective effect of Did was observed on the 7th day after DOX treatment. Results: DOX delayed body growth and caused cardiac tissue injury, oxidative stress, and mitochondrial dysfunction. Similar experiments in H9C2 cardiomyocytes showed that DOX reduced cell viability, increased generation of reactive oxygen species (ROS) and fragmentation of DNA, decreased mitochondrial membrane potential, and induced cardiomyocyte apoptosis. However, all of these adverse effects were suppressed by Did pretreatment. Did increased protein expression of glutamate-L-cysteine ligase catalytic subunit (GCL), heme oxygenase 1 (HO-1), and nuclear factor erythroid 2-related factor 2 (Nrf2). Besides, Did also induced activation of PI3K/AKT. Conclusion: These findings indicated Did prevented DOX-induced cardiac injury and apoptosis via activating PI3K/AKT/Nrf2 signaling pathway.