血管紧张素Ⅱ对人脐静脉内皮细胞衰老的诱导作用及对端粒酶活性的影响*

摘要

目的 观察血管紧张素Ⅱ(angiotensinⅡ,AngⅡ)对人脐静脉内皮细胞(human umbilical vein endothelial cell,HUVECs)衰老的诱导作用及对端粒酶活性的影响.方法 体外培养HUVECs,采用CCK-8法检测细胞存活率,用AngⅡ(终浓度10-6 mol/L)干预,分为对照组和AngⅡ诱导组.β-半乳糖苷酶活性采用免疫化学染色方法,流式细胞术检测细胞周期来反映细胞的增殖能力;用聚合酶链反应-酶联免疫吸附法(PCR-ELISA)检测端粒酶活性.结果 与对照组比较,10-6 mol/L AngⅡ诱导组存活的细胞数为对照组的(77.15±6.83)%;(71.10±6.81)%的细胞呈现β-半乳糖苷酶阳性染色,流式细胞仪检测细胞周期多停滞于G0/G1期[(84.11±7.92)%],证实细胞衰老;与对照组相比,10-6 mol/L AngⅡ诱导组端粒酶活性明显下降(P<0.01).结论 AngⅡ可以诱导HUVECs衰老,其机制可能与抑制衰老细胞端粒酶活性有关.%Objective To evaluate the telomerase activity of senescent human umbilical vein endothelial cells ( HUVECs ) induced by angiotensin II ( Ang II ). Methods The cell viability of HUVECs cultured in vitro was assessed by CCK - 8. HUVECs were divided into two groups: control group and Ang II group ( stimulated with Ang II10 -6 mol/L for 48 h ). The β - galactosidase ( β - gal ) activity and cell proliferation activity were evaluated by immunocytochemitry and flow cytometry, respectively. Telomerase activity was assessed by polymerase chain reaction - enzyme linked immu-nosorbent assay ( PCR - ELISA ). Results The cell viability of AngII group was ( 77. 15 ±6. 83 )% of the control group, while the (3 - gal positive rate in Ang II group was ( 71. 10 ± 6. 81 )%. Meanwhile, the G0/G1 stagnation rate was ( 84. 11 ±7. 92 )% in Ang II group, with significantly lowered telomerase activity ( P <0. 01 ). Conclusion Ang II can induce HUVECs senescence, which may be relevant to the down - regulated the telomerase activity.