烟酸抑制血管紧张素Ⅱ诱导的内皮细胞凋亡

目的探讨烟酸对血管紧张素Ⅱ诱导的人脐静脉内皮细胞(HUVECs)凋亡的影响。方法分别使用不同浓度烟酸(0.25 mM,0.5 mM或1.0 mM)预处理HUVECs不同时间(1 h、3 h、6 h、12 h)后,使用血管紧张素Ⅱ(1μM)诱导HUVECs凋亡。终端转移酶介导的dUTP缺口标记技术(TUNEL法)检测内皮细胞的凋亡指数;H2DCF-DA荧光标记法测定细胞内氧自由基(ROS)的生成。结果预处理一定时间后,烟酸能抑制血管紧张素II诱导的HUVECs的凋亡,而且这种抑制呈浓度依赖性。HUVECs在使用1 mM烟酸预处理6 h后,血管紧张素II加烟酸(AngII+Niacin)组与血管紧张素Ⅱ(AngII)组相比,ROS的生成有明显降低(P<0.05)。结论烟酸能抑制AngII诱导的HUVECs凋亡,抑制ROS生成是可能的机制之一。

Study on inhibition of niacin on apoptosis of human endothelial cells induced by angiotensin II

Objective To study the influence of niacin on apoptosis of human umbilical vein endothelial cells（HUVECs） induced by angiotensin Ⅱ.Methods HUVECs were pretreated with different concentrations of niacin（0.25 mM,0.5 mM and 1.0 mM） for different duration（1 h,2 h,6 h and 12 h）,then HUVECs were treated with angiotensin Ⅱ（1 μM） for 12 h.According to the protocol of manufacturer,TUNEL assay was used to detect changes of apoptosis index in HUVECs,and H2DCF-DA fluorescent labeling method was applied to detect intracellular ROS（reactive oxygen species）production.Results In HUVECs,niacin had the ability to inhibit apoptosis induced by angiotensin Ⅱ in a concentration-dependent way.The further study indicated that niacin inhibited ROS production induced by angiotensin Ⅱ in HUVECs.Conclusion Niacin can inhibit apoptosis in HUVECs induced by angiotensin Ⅱ,and one of the possible mechanism is its inhibition on intracellular ROS production.