Oxidative stress-induced vascular endothelial cell (VEC) injury is a major mechanism in the initiation and development of atherosclerosis. Lunasin, a soybean-derived 43-aa peptide, has been previously shown to possess potent antioxidant and anti-inflammatory activities other than its established anticancer activities. This study investigated the effects of lunasin on protecting VECs from oxidative damage and inhibiting atherosclerotic plaque progression in apolipoprotein E-deficient (ApoE-/-) mice and explored its underlying mechanism. Biochemical and histologic analyses were performed by using EA.hy926 human VECs and a high-fat diet (HFD) ApoE-/- mouse atherosclerosis model. Our data indicated that lunasin attenuated H2O2-induced, mitochondria-dependent endothelial apoptosis via down-regulating Bax and up-regulating Bcl-2, inhibiting the mitochondrial depolarization, and reducing the release of cytochrome c, as well as decreasing the activation of caspase-9 and caspase-3 in vitro and in vivo. Mechanic studies showed that lunasin significantly up-regulated heme oxygenase-1 via the PI3K/Akt/nuclear factor erythroid 2-related factor 2/antioxidant response element pathway, and reduced H2O2-induced ROS production in VECs, thereby attenuating oxidant-induced endothelial injury and inhibiting atherosclerotic plaque progression in ApoE-/- mice. In conclusion, our in vitro and in vivo data suggest that lunasin protects VECs from oxidative damage by enhancing heme oxygenase-1 expression via activation of the PI3K/Akt/nuclear factor erythroid 2-related factor 2/antioxidant response element pathway and inhibiting mitochondria-dependent apoptosis, thereby effectively attenuating atherosclerosis in HFD-fed ApoE-/- mice. Lunasin may act as a potential therapeutic agent for the prevention and treatment of atherosclerosis.-Gu, L., Ye, P., Li, H., Wang, Y., Xu, Y., Tian, Q., Lei, G., Zhao, C., Gao, Z., Zhao, W., Tan, S. Lunasin attenuates oxidant-induced endothelial injury and inhibits atherosclerotic plaque progression in ApoE-/- mice by up-regulating heme oxygenase-1 via PI3K/Akt/Nrf2/ARE pathway.
Keywords: atherosclerosis; endothelium; oxidative stress.