Acteoside ameliorates doxorubicin-induced cardiotoxicity by suppressing ferroptosis through activation of the KEAP1/NRF2 pathway

Acteoside attenuates doxorubicin-induced cardiotoxicity and ferroptosis. • Acteoside preserves mitochondrial function in doxorubicin-exposed cardiomyocytes. • Acteoside promotes KEAP1 degradation and activates NRF2 signaling. • NRF2 inhibition attenuates the cardioprotective and anti-ferroptotic effects of ACT. : Doxorubicin (DOX)-induced cardiotoxicity (DIC) is a major limitation to the clinical use of DOX, highlighting the need for effective cardioprotective strategies. Although acteoside (ACT), a natural compound with antioxidant properties, has shown potential cardioprotective effects, its role in DIC, particularly in the regulation of ferroptosis, remains unclear. This study therefore investigated the protective effects of ACT against DIC and the underlying molecular mechanisms. Using C57BL/6 mice in vivo and H9c2 cells in vitro, we evaluated cardiac function, myocardial injury and histopathological alterations, ferroptosis-related changes, and key regulatory proteins. ACT significantly attenuated DOX-induced cardiac dysfunction, myocardial injury, and fibrosis. These protective effects were accompanied by suppression of ferroptosis, as evidenced by reduced iron accumulation and lipid peroxidation and restored expression of glutathione peroxidase 4 (GPX4) and the cystine/glutamate transporter (xCT). ACT also preserved mitochondrial membrane potential and reduced mitochondrial reactive oxygen species (ROS) levels, thereby alleviating mitochondrial dysfunction. Mechanistically, ACT may interact with Kelch-like ECH-associated protein 1 (KEAP1) and promoted KEAP1 degradation, thereby facilitating the nuclear translocation of nuclear factor erythroid 2-related factor 2 (NRF2) and increasing the expression of downstream antioxidant proteins, including heme oxygenase-1 (HO-1). Moreover, the NRF2 inhibitor ML385 significantly attenuated the protective effects of ACT, supporting the involvement of NRF2 signaling in ACT-mediated cardioprotection. Collectively, these findings suggest that ACT protects against DIC, at least in part, by promoting KEAP1 degradation, activating NRF2 signaling, and suppressing ferroptosis. This figure summarizes the mechanism by which ACT alleviates DOX-induced cardiotoxicity through the suppression of ferroptosis. ACT promotes KEAP1 degradation, reduces KEAP1-mediated NRF2 degradation, and enhances NRF2 nuclear translocation and downstream antioxidant and anti-ferroptotic signaling. These effects upregulate HO-1, xCT, and GPX4, reduce lipid ROS accumulation, improve mitochondrial function, and suppress cardiomyocyte ferroptosis. Collectively, the cardioprotective effects of ACT are mediated, at least in part, through activation of the KEAP1/NRF2 axis. Download: Download high-res image (175KB) Download: Download full-size image