Nrf2-mediated inhibition of ferroptosis contributes to the amelioration of atherosclerosis by polydatin

Abstract

Polydatin is a bioactive compound extracted from the roots of Reynoutria japonica Houtt. It has demonstrated various protective effects on the cardiovascular system. However, the underlying molecular mechanisms through which polydatin exerts its effects in atherosclerosis (AS) remain largely unclear, particularly regarding the involvement of the ferroptosis pathway in its anti-atherosclerotic action. This study aims to investigate the anti-atherosclerotic effects of polydatin and its potential mechanisms, with a primary focus on the ferroptosis pathway. To this end, we employed an ApoE^−/− mouse model and endothelial cells exposed to oxidized low-density lipoprotein (ox-LDL). We analyzed atherosclerosis progression, endothelial function, and ferroptosis both in vitro and in vivo using various biological and biochemical techniques. To further explore the underlying mechanisms of polydatin's effects, Nrf2 expression was silenced using siRNA. Polydatin inhibited atherosclerosis in vivo and improved endothelial function in vitro. We evaluated ferroptosis-related markers, including ferrous iron, glutathione, malondialdehyde, lipid reactive oxygen species (ROS), GPX4, and SLC7A11, as well as overall ROS production, mitochondrial membrane potential, and mitochondrial ROS. The results indicated that polydatin suppressed ferroptosis both in vivo and in vitro. Moreover, the ferroptosis inducer erastin counteracted the endothelial cytoprotective effects of polydatin. Mechanistically, polydatin significantly enhanced Nrf2 nuclear translocation in both the aortic tissues of ApoE^−/− mice and ox-LDL-stimulated endothelial cells. Furthermore, silencing Nrf2 markedly abrogated the protective effects of polydatin on endothelial ferroptosis and impaired cellular function. Collectively, these findings demonstrate that modulating Nrf2-dependent ferroptosis contributes to the ability of polydatin to mitigate atherosclerosis and protect endothelial cells from injury.