NADPH氧化酶4在AGEs诱导内皮细胞活性氧生成中的作用研究

Role of NADPH oxidase 4 in generation of intracellular ROS in endothelial cells stimulated by AGEs

目的晚期糖基化终末产物(AGEs)能诱发细胞内活性氧(ROS)生成增多而引起内皮细胞损伤,从而促进动脉粥样硬化的发生和发展,本组探讨AGEs刺激下内皮细胞ROS的生成及NADPH氧化酶4(Nox4)的作用。方法培养人脐静脉内皮细胞(HUVECs),观察AGEs刺激下HUVECs细胞Nox4表达和ROS生成情况,应用RNA干扰技术沉默Nox4后,观察细胞内ROS的变化,分析Nox4的作用。结果 AGEs刺激后HUVECs细胞内ROS增加,而Nox4 siRNA转染后能显著降低内皮细胞ROS水平;Nox4 siRNA转染可以使基础水平的ROS减少45.9%,并对AGEs刺激后的ROS增加有明显的抑制作用。结论 Nox4是内皮细胞ROS生成过程中发挥调控作用的关键靶点,阻断Nox4能有效地抑制AGEs诱导的内皮细胞氧化损伤,进而可能阻遏动脉粥样硬化的发生和发展。

Objective Advanced glycation end products （AGEs） can induce the intracellular generation of reactive oxygen species （ROS） and cause the dysfunction of endothelial cells. This may accelerate development of vascular atherosclerosis. We investigated the role of NADPH oxidase 4 （Nox4） in the generation of intracellular ROS in endothelial cells stimulated by AGEs. Methods Human umbilical vein endothelial cells （HUVECs） were cultured and incubated with AGEs and intracellular ROS was measured with 2＇, 7＇-dichlorodihydrofluorescein diacetate （DCF-DA）. siRNA was used to silence Nox4. The role of Nox4 in the generation of ROS was observed. Results After AGEs stimulation,ROS in HUVECs was significantly elevated,while Nox4 siRNA transfection inhibited the generation of ROS significantly. Nox4 siRNA transfection reduced ROS at basal level by 45.9%, and significantly inhibited AGEs--induced ROS elevation. Conclusion Altogether, the results demonstrate that Nox4 is the major source of intracellular ROS in endothelial cells,and indicate potential targets for the inhibition of the atherogenic signals triggered by AGEs.