Protective Effect Of Scutellarin On Vascular Endothelial Cell Injury Induced By Oxidative Stress And Its Mechanism

Objective: To explore the protective effects of scutellarin on vascular endothelial cell injury induced by oxidative stress and to investigate its mechanisms.Methods: Peroxide hydrogen (H₂O₂) was used to induce injury of human umbilical vein endothelial cells (HUVEC). The cell Survival rate was evaluated with MTT assay to explore the protective effect of scutellarin on injury of vascular endothelial cells. The activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) and catalase (CAT) was detected in H₂O₂-induced HUVEC injury. Incubated with 1,1-dipheyl-2-picrylhydrazyl (DPPH) medium could reduce the endothelium-dependent relaxation response (EDRR) to acetylcholine (Ach) in the isolated rabbit thoracic aortic rings. The pathomorphological changes in rabbit thoracic aortic rings were also observed by transmission electron microscope.Results: HUVEC was incubated with lmmol/L H₂O₂ for 4 h, the cell viability decreased significantly (P＜0.05 vs normal control group); scutellarin can promote the cell viability of HUVEC induced by H₂O₂ (P＜0.05 vs H₂O₂—injury group); scutellarin could concentration-dependently protect the activity of SOD and GSH-PX (P＜0.05 vs H₂O₂ injury group). 0.25μmol/L of DPPH significantly produced a decrease of EDRR induced by Ach after incubated with the rabbit thoracic aortic rings for 20 min, and scutellarin showed the protection on the decrease of endothelium-derived relaxation factor (EDRF).Conclusion: Scutellarin showed protective effects on vascular endothelial cells induced by oxidative stress and the probable mechanisms may be closely associated with its promoting the activity of antioxidases.