Effects Of Sirt1 On Homocysteine-induced Endothelial Cell Senescence

Objective:To explore the effect of Sirt1 on homocysteine-induced aging of vascular endothelial cells.Methods:HUVEC were cultured in vitro,and cells were divided into normal control group,Hcy group with different concentrations(50?M,200?M,500?M,1000?M,2000?M),10mg/mL D-Gal group(positive control),2000?M Hcy+50?M RSV group,and cultured 24 hours,use CCK-8 to detect proliferative activity,SA-?-Gal staining to detect endothelial aging,cell cycle analysis of each group's blockage,DCFH-DA to detect intracellular ROS levels;PCR ELISA method to detect intracellular telomerase activity;Western-blot detection of Sirt1 protein levels in cells.Results:According to the CCK-8 test,compared with the control group,the cell proliferation activity of each Hcy group decreased with increasing concentration,and RSV partially improved the proliferation activity;by SA-?-Gal staining,compared with the control group,each Hcy group The positive rate of the group increased,with a certain concentration dependence,RSV can reduce the positive rate of SA-?-Gal cells;according to cell cycle analysis,compared with the control group,each Hcy group blocked cells in the G0/G1 phase,The proportion of cells in S phase and G2/M phase is significantly reduced.RSV can partially reduce the number of cells in G0/G1 phase and increase the proportion of cells in S phase and G2/M phase.In ROS detection,the fluorescence intensity of the Hcy group is higher than that of the control group,which has a certain concentration dependence.RSV pretreatment can reduce ROS levels.By Western blot and telomerase activity detection,the Sirt1 protein level and telomerase activity of the Hcy group were significantly lower than those of the control group,and RSV increased Sirt1 protein level and telomerase activity.Conclusion:Hcy can promote endothelial cell senescence and reduce telomerase activity through oxidative stress.RSV partially improves the oxidative damage and aging of endothelial cells and increases telomerase activity,suggesting that Sirt1 may play aprotective role in Hcy-induced endothelial cell senescence.