Abstract: In the present study, corosolic acid (CA) was extracted and separated from Folium Eriobotryae. A Cu2+-induced low density lipoprotein (LDL) oxidation model was employed to evaluate the inhibitory effect of CA on LDL oxidation in vitro, and a human aortic endothelial cell (HAEC) model of oxidative damage induced by (2,2’-azobis-2-methyl-propanimidamide dihydrochloride, AAPH) was employed to evaluate the protective effect of CA on oxidative damage. In the dose range of 10-100 μmol/L, CA effectively extended the lag time of the Cu2+-induced LDL oxidation process, reduced the area under the oxidation kinetic curve (AUC) and inhibited the generation of lipid peroxide indicating that CA could effectively inhibit LDL oxidation induced by Cu2+. In the cellular experiment at the dose range of 2-10 μmol/L, CA effectively reduced LDH leakage induced by AAPH, maintained the integrity of cell structure, enhanced the activities of antioxidant enzymes such as superoxide dismutase (SOD) and glutathione peroxidase (GPx) and therefore oxidative stress resistance, reduced the proportion of sub-G1/G0 cells and necrosis or apoptosis induced by AAPH. These results demonstrated that CA could elevate cellular antioxidant capacity, maintain the integrity of cellular structure, and ultimately protect HAECs against oxidative stress damage induced by AAPH.

Key words: Folium Eriobotryae, corosolic acid, low density lipoprotein(LDL), vascular endothelial cells, lipid peroxidation