线粒体凋亡通路在棕榈酸诱导的血管内皮细胞凋亡中的作用

Role of mitochondrial apoptosis pathway in palmitic acid-induced cell apoptosis in vascular endothelial cells

目的探讨线粒体凋亡通路在棕榈酸诱导的人脐静脉血管内皮细胞(human umbilical vein endothelial cells,HUVECs)凋亡中的作用。方法不同浓度棕榈酸(0.1、0.2、0.4、0.8 mmol·L^(-1))作用HUVECs(0、12、24、48 h),MTT法检测HUVECs增殖能力;免疫荧光法检测HUVECs细胞内活性氧(reactive oxygen species,ROS)的表达水平;免疫印迹法检测HUVECs中AIF、Cyt-C、cleaved caspase-3、Bcl-2、Bax等线粒体凋亡通路蛋白的表达水平;TUNEL法检测细胞内凋亡水平。结果 0.4 mmol·L^(-1)棕榈酸作用HUVECs 24 h时,细胞增殖率明显降低;AIF、Cyt-C、cleaved caspase-3、Bax/Bcl-2的水平明显升高(P<0.05),细胞凋亡水平明显增高(P<0.05);线粒体通透性抑制剂环孢素A (ciclosporine A, CsA)预处理组HUVECs凋亡水平明显下调(P<0.05)。结论棕榈酸所致血管内皮细胞损伤的发病机制可能与线粒体凋亡相关通路密切关联,此研究对脂毒性心肌损伤的防治有重要意义。

Aim To explore the role of mitochondrial apoptosis pathway in palmitic acid(PA)-induced cell apoptosis in human umbilical vein endothelial cells(HUVECs). Methods HUVECs were exposed to different concentrations of PA (0.1, 0.2, 0.4, 0.8 mmol·L^-1 ) for 24 h and different time points of 0.4 mmol·L^-1 PA (0, 12, 24, 48 h). Cell viability was measured by MTT. The expression of reactive oxygen species(ROS) in HUVECs was detected by immunofluorescence. The level of intracellular apoptosis was detected by TUNEL assay. The protein expressions of mitochondrial apoptosis pathway proteins such as AIF, Cyt-C, cleaved caspase-3, Bcl-2, Bax were determined by Western blot. Results HUVECs exposed to PA at 0.4 mmol·L^-1 for 24 h showed a decrease in their viability and an increase in the level of AIF, Cyt-C, cleaved caspase-3, Bax/Bcl-2 ( P <0.05). Cell apoptosis level was significantly up-regulated ( P <0.05). The intracellular apoptosis levels in the vascular endothelial cells treatment with mitochondrial apoptosis pathway inhibitor ciclosporine A (CsA) were significantly lower than those of PA group ( P <0.05). Conclusion Activated mitochondrial apoptosis pathway might play an important role in PA-induced cell apoptosis in vascular endothelial cells.