枸杞多糖对血管紧张素II诱导的血管内皮细胞衰老及P53和P16表达的影响

Effect of lycium bararum polysaccharides on angiotensin II-induced senescence of human umbilical vein endothelial cells and expressions of P53 and P16

目的观察枸杞多糖对血管紧张素I(IAngII)诱导人脐静脉血管内皮细胞(HUVECs)衰老及对细胞衰老相关基因P53和P16表达的影响,以探讨其抗衰老作用及机制。方法体外培养HUVECs加入终浓度10-6mol/LAngII诱导细胞衰老,建立内皮细胞衰老模型。实验分为空白对照组、AngII模型组和枸杞多糖组;β-半乳糖苷酶染色法鉴定内皮细胞衰老状态;流式细胞技术分析细胞周期变化;CCK-8法检测细胞存活率情况;Westernblotting法检测P53、P16蛋白的表达。结果 AngII模型组与空白对照组比较,β-gal阳性染色率明显增多,细胞周期多停滞于G0/G1期,S期细胞逐渐减少,细胞存活率明显下降,P53、P16蛋白表达水平明显上调。给予枸杞多糖处理后改善了细胞衰老状态,β-gal阳性染色率减少,G0/G1期细胞减少,S期细胞逐渐增多,细胞存活率增多,P53、P16蛋白的表达较AngII组下调。结论枸杞多糖能够抑制AngII诱导HUVECs衰老,其作用机制可能是通过下调P53及P16的表达而实现的。

Objective To investigate the role of lycium bararum polysaccharides（LBP） on angiotensin II（AngII）-induced senescence of human umbilical vein endothelial cells（HUVECs） and expressions of P53 and P16 and explore the mechanism of LBP against aging.Methods HUVECs cultured in vitro were stimulated with 1×10-6 mmol/L AngII to induce cell senescence,which was identified using β-gal staining.Flow cytometry was used for analyzing the cell cycle changes,and the cell viability was assessed using CCK-8 method.Western blotting was employed to detect the expression of P53 and P16 in the exposed cells.Results Compared with the control cells,the cells positive for β-gal staining was significantly increased in AngII group,and showed cell cycle arrest at G 0 /G 1 phase with decreased S-phase cell percentage and cell viability.The expression levels of P53 and P16 were significantly increased in the cells with AngII exposure（P〈0.05）.LBP treatment of AngII-exposed cells resulted in decreased β-gal-positive cells with a reduction in G 0 /G 1 phase cells and an increase in S phase cells.LBP treatment also increased the cell viability and significantly decreased the expression levels of P53 and P16（P〈0.05）.Conclusion LBP can delay AngII-induced aging of HUVECs possibly by down-regulating the expression of P53 and P15.