TSG Up-regulate XIAP and Inhibit Apoptosis of Human Umbilical Vein Endothelial Cells

Objective: To investigate the effect of 2,3,5,4′-tetrahydroxystilbene-2-O-β-D-glucoside(TSG) against hydrogen peroxide(H2O2) induced human umbilical vein endothelial cells(HUVECs) apoptosis and the expressions of X-linked inhibitor of apoptosis protein(XIAP), Caspase-9. Methods: HUVECs were divided into six groups: control group, H2O2group(300 μmol·L-1), TSG group(10 μmol·L-1TSG + 300 μmol·L-1H2O2), TSG and Embelin combination group(30 μmol·L-1Embelin + 10 μmol·L-1TSG + 300μmol·L-1H2O2), TSG alone treatment group(10 μmol·L-1), and Embelin group(30 μmol·L-1). The viability of HUVECs was determined with MTT as- say. Hoechst 33258 staining was used to observe the morphology of apoptosis. The mRNA expression of XIAP, Caspase-9was measured using RT-PCR. The protein expression of XIAP, Caspase-9 was detected by Western blotting. Results: Treatment HUVECs with H2O2 significantly increased the apoptosis, reduced the cell viability, decreased the expressions of XIAP and elevated Caspase-9 expression(P0.01). The expression of XIAP was inhibited by treated with Embelin alone. Compared with H2O2 group, the apoptosis rate reduced, the cell viability enhanced, the expressions of XIAP increased and Caspase-9 reduced markedly after TSG pretreated(P0.01). Combination of Embelin and TSG decreased the cell apoptosis than pretreatment of TSG, and the expression of XIAP reduced, Caspase-9 increased significantly(P0.01). Conclusion: TSG could inhibit H2O2-induced apoptosis in HUVECs, and the mechanism was associated with the expressions of XIAP and Caspase-9.