白藜芦醇通过抑制细胞凋亡延缓内皮细胞衰老

Resveratrol protects endothelial cells from senescence via inhibition of apoptosis

目的探讨SIRT1在内皮细胞自然衰老过程中的变化和作用机制。方法连续培养传代人脐静脉内皮细胞(HUVECs)38代,选取第1、5、10、15、20、25、30和35代细胞做Western blot检测内皮细胞自然衰老过程中SIRT1蛋白含量变化以及Annexin V-FITC法测定内皮细胞凋亡水平变化。选取第25代细胞,给予SIRT1激动剂白藜芦醇(30μmol/L)干预,β-半乳糖苷酶染色法检测内皮细胞的衰老程度以及Annexin V-FITC法测定内皮细胞凋亡水平。结果随着代数增加,内皮细胞上的SIRT1蛋白表达逐渐降低(P<0.01),内皮细胞凋亡率逐渐升高(P<0.01);给予第25代细胞白藜芦醇干预后,内皮细胞上的SIRT1表达升高(P<0.01),β-半乳糖苷酶阳性细胞率降低(P<0.01),凋亡率也降低(P<0.05)。结论内皮细胞自然衰老过程中,SIRT1的表达会降低;给予白藜芦醇干预后,能逆转内皮细胞的衰老,其作用机制可能与SIRT1降低了内皮细胞凋亡水平有关。

AIM To investigate the changes and functions of SIRT1, a member of the sirtuin family, in natural senescence of endothelial cells and its mechanism. METHODS Human umbilical vein endothelial cell （HUVECs） were continuously cultured and passaged for 38 generations. Cells of the 1st, 5th, 10th, 15th, 20th, 25th, 30th and 35th generations were selected and Western blot was performed to detect the SIRT1 expressions of endothelial cells. Annexin V-FITC was conducted to measure the changes of apoptosis in endothelial cells. Cells of the 25th generation were subsequently chosen to be subjected to the SIRT1 agonist resveratrol （30 μmol/L） and SA-β-Gal staining and Annexin V-FITC methods were used to detect the aging degree and the changes of apoptosis in endothelial ceils, respectively. RESULTS As the passages increased, protein expressions of SIRT1 in the endothelial ceils decreased （P 〈 0. 01 ） and the apoptosis rate increased （P 〈 0. 01 ）. After resveratrol intervention in the 25th generation cells, the protein expressions of SIRT1 increased, and SA-13-Gal positive cells （P 〈 0. 01 ） and apoptosis rates （P 〈 0.05） declined. CONCLUSION During the natural senescence of endothelial cells, expression of SIRT1 decreases but resveratrol could reverse the senescence, possibly by decreasing the apoptosis levels of endothelial cells.