XIAP Mediated TSG Antagonistic To Oxidative Damage Effect In Human Umbilical Vein Endothelial Cells

Aim: To study the antiapoptotic effects of2,3,5,4′-tetrahydroxystilbene-2-O-β-D-glucoside （TSG） on H₂O₂-induced apoptosis in human umbilical vein endothelial cells（HUVECs） and to explore whether through promoting the expressions of XIAP,decreasing the expression of Caspase-9and Caspase-3.Methods: HUVECs were pretreated with TSG （1,10,100μM） for24hours, thentreated with300μM H₂O₂. Observe the apoptosis rates of HUVECs and theexpression of XIAP, the expression of Caspase-9and Caspase-3. The viability ofHUVECs was detected by MTT assay. The morphology of apoptosis was observed byHoechst33258staining. The protein expressions of XIAP, Caspase-9, Caspase-3weredetected by Western Blot.Results: The results of morphological showed300μM H₂O₂significantly increasedthe apoptosis and reduced the cell viability compared with control; compared withH₂O₂group, the apoptosis rate decreased and the cell viability enhanced in TSG group;compared with TSG pretreated group, pretreated with Embelin for6hours and TSGsignificantly increased the apoptosis. Only treatment with Embelin or TSG has nosignificant difference compared with control.The results of RT-PCR and Western Blot display the expression of XIAP wasdecreased and the expression of Caspase-3, Caspase-9were increased after treatingwith H₂O₂compared with control; the expression of XIAP was up-regulated while theexpression of Caspase-3, Caspase-9were down-regulated with a dose-dependentmanner after treating with1-100μM TSG compared with H₂O₂group; compared withTSG group, the expression of XIAP down regulated and the expression of Caspase-3,Caspase-9up regulated after pretreated with30μM Embelin for6hours then treatingwith10μM TSG. Conclusion:TSG promot the expression of XIAP antagonizes oxidative damage in humanumbilical vein endothelial cells...