SIRT6激活Nrf2/ARE信号通路对受AngⅡ诱导的血管内皮细胞的影响

Influence of SIRT6 activated Nrf2/ARE signaling pathway on Ang Ⅱ induced vascular endothelial cells

目的:研究沉默信息调节因子6(SIRT6)激活Nrf2/ARE信号通路对受血管紧张素II(Ang II)诱导的血管内皮细胞的影响。方法:将人主动脉内皮细胞(HAEC)均分为常规对照组、Ang II组(使用Ang II培养),Ang II+空载体(EV)组、Ang II+SIRT6组、Ang II+阴性对照(NC)siRNA组、Ang II+SIRT6 siRNA组(Ang II组基础上转染SIRT6 siRNA)、Ang II+SIRT6+NC siRNA组及Ang II+SIRT6+Nrf2 siRNA组,各组样本量均为3。观察比较各组Nrf2核蛋白、HO-1 mRNA相对表达量、Nrf2/ARE相对荧光量、细胞增殖能力、Caspase-3相对活性、LDH释放量及ROS产生相对量。结果:与Ang II+EV组比较,Ang II+SIRT6组Nrf2核蛋白[(1.892±0.338)比(3.221±0.225)]、HO-1 mRNA[(1.919±0.239)比(3.857±0.480)]相对表达量、Nrf2/ARE相对荧光量[(1.848±0.121)比(2.933±0.299)]均显著升高(P均=0.001)。与Ang II+NC siRNA组比较,Ang II+SIRT6 siRNA组Nrf2核蛋白[(1.892±0.233)比(0.514±0.034)]、HO-1 mRNA相对表达量[(1.880±0.240)比(0.483±0.153)]、Nrf2/ARE相对荧光量[(1.837±0.263)比(0.481±0.152)]均显著降低(P均=0.001)。与Ang II+SIRT6+NC siRNA组比较,Ang II+SIRT6+Nrf2 siRNA组Nfr2核蛋白相对表达量[(3.261±0.289)比(0.986±0.112)]、Nrf2/ARE相对荧光量[(2.989±0.431)比(0.930±0.126)]和细胞增殖能力[(91.743±11.108)%比(55.981±13.058)%]显著降低,Caspase-3相对活性[(1.242±0.257)%比(3.173±0.352)%]、LDH释放量[(9.387±2.479)%比(19.233±4.091)%]及ROS产生相对量[(2.214±0.295)比(4.435±0.494)]显著升高(P<0.05或<0.01)。结论:SIRT6可通过加强Nrf2/ARE氧化还原信号的激活来保护血管内皮细胞免受Ang II诱导的细胞凋亡和氧化应激。

Objectives:To study influence of SIRT6 activated Nrf2/ARE signaling pathway on angiotensin(Ang)Ⅱ-induced vascular endothelial cells.Methods:Human aortic endothelial cell(HAECs)were randomly and equally divided into routine control group,Ang Ⅱ group(cultivated with Ang Ⅱ),Ang Ⅱ+empty vector(EV)group,Ang Ⅱ+SIRT6 group,Ang Ⅱ+negative control(NC)siRNA group,Ang Ⅱ+SIRT6 siRNA group,Ang Ⅱ+SIRT6+NC siRNA group and Ang Ⅱ+SIRT6+Nrf2 siRNA group,n=3 in each group.Relative expression amounts of Nrf2 nuclear protein and HO-1 mRNA,relative fluorescence amount of Nrf2/ARE,cell proliferation capacity,relative activity of caspase-3,LDH release amount and relative production amount of ROS were observed and compared among all groups.Results:Compared with Ang Ⅱ+EV group,there were significant rise in relative expression amounts of Nrf2 nuclear protein[(1.892±0.338)vs.(3.221±0.225)]and HO-1 mRNA[(1.919±0.239)vs.(3.857±0.480)],relative fluorescence amount of Nrf2/ARE[(1.848±0.121)vs.(2.933±0.299)]in Ang Ⅱ+SIRT6 group(P=0.001 all).Compared with Ang Ⅱ+NC siRNA group,there were significant reductions in relative expression amounts of Nrf2 nuclear protein[(1.892±0.233)vs.(0.514±0.034)]and HO-1 mRNA[(1.880±0.240)vs.(0.483±0.153)],relative fluorescence amount of Nrf2/ARE[(1.837±0.263)vs.(0.481±0.152)]in Ang Ⅱ+SIRT6 siRNA group,P=0.001 all.Compared with Ang Ⅱ+SIRT6+NC siRNA group,there were significant reductions in relative expression amounts of Nfr2 nuclear protein[(3.261±0.289)vs.(0.986±0.112)],relative fluorescence amount of Nrf2/ARE[(2.989±0.431)vs.(0.930±0.126)]and cell proliferation capacity[(91.743±11.108)%vs.(55.981±13.058)%],and significant rise in relative activity of caspase-3[(1.242±0.257)%vs.(3.173±0.352)%],LDH release amount[(9.387±2.479)%vs.(19.233±4.091)%]and relative production amount of ROS[(2.214±0.295)vs.(4.435±0.494)]in Ang Ⅱ+SIRT6+Nrf2 siRNA group(P<0.05 or<0.01).Conclusion:SIRT6 can protect vascular endothelial cells from Ang Ⅱ induced apoptosis and oxidative stress induced by Ang Ⅱ by enhancing activation of Nrf2/ARE redox signals.