硫化氢通过调节Sirt1/eNOS信号通路延缓人脐静脉内皮细胞衰老

摘要

目的:我们既往研究已证实外源性硫化氢能够延缓内皮细胞衰老,本研究拟进一步探讨沉默信息调节因子1(Sirt1)与内皮型一氧化氮合酶(eNOS)系统对硫化氢抗内皮细胞衰老作用的影响.方法:建立葡萄糖(33 mmol/L)诱导的人脐静脉内皮细胞(HUVECs)衰老模型,根据细胞活力、衰老相关β-半乳糖苷酶(SA-β-Gal)染色阳性率和纤溶酶原激活物抑制剂1(PAI-1)的表达水平评估HUVECs衰老;同时采用RNA干扰技术抑制Sirt1蛋白表达,检测eNOS表达及衰老相关指标.结果:HUVECs经高糖处理后,细胞活力减低,SA-β-Gal阳性细胞比例增加,PAI-1表达增高,Sirt1及eNOS表达均明显减少(P<0.05);与高糖处理组比较,100 μmol/L硫氢化钠(硫化氢供体)处理组的细胞活性增加,SA-β-Gal染色阳性细胞比例及PAI-1蛋白表达显著下降,Sirt1及eNOS蛋白表达增加,NO含量增加(P<0.05).与硫化氢处理组比较,Sirt1 siRNA处理后 eNOS表达减少,PAI-1表达增加,SA-β-Gal染色阳性细胞数目增多,NO含量减少(P<0.05或P<0.01).结论:硫化氢通过上调Sirt1、增加eNOS 表达而促进NO的合成,从而抵抗高糖诱导的HUVECs衰老.%AIM:To explore the role of Sirt1/eNOS signalling pathway in the protective effect of hydrogen sul-phide(H2S)against endothelial cell senescence induced by high glucose.METHODS:High glucose(33 mmol/L)was applied to induce senescence in primary human umbilical vein endothelial cells(HUVECs).The cell viability,the propor-tion of senescence-associated β-galactosidase(SA-β-Gal)positive cells and the plasminogen activator inhibitor 1(PAI-1) expression were detected to assess the senescence model.Mean while,Sirt1 siRNA was used to examine the effect of Sirt 1 on eNOS expression and the senescence-related parameters.RESULTS: Treatment of HUVECs with high glucose de-creased the cell viability slowly with a larger proportion of the cells stained with SA-β-Gal, and the protein expression of PAI-1 was dramatically increased.The increased cell viability,reduced SA-β-Gal positive cells and decreased protein ex-pression of PAI-1 were detected after sodium hydrosulfide(NaHS,100 μmol/L)treatment.Furthermore,NaHS treatment upregulated the protein expression of Sirt 1 and eNOS,and eventually increased the production of nitric oxide(NO).CON-CLUSION:Exogenous H2S modulates Sirt1/eNOS/NO pathway to prevent HUVECs against high glucose-induced senes-cence.