槲皮素对脂多糖诱导的NRK-52E细胞凋亡和线粒体功能的作用研究

Effects of Quercetin on Apoptosis and Mitochondrial Function of NRK-52E Cells Induced by Lipopolysaccharide

目的:探讨槲皮素对脂多糖(LPS)诱导的大鼠肾小管上皮细胞(NRK-52E)线粒体损伤的保护作用及对细胞凋亡通路的影响。方法:采用LPS诱导NRK-52E建立脓毒症肾损伤体外模型,将细胞分为对照组、LPS组、LPS+槲皮素组;MTT比色法检测NRK-52E细胞活力,DCFH-DA、MitoROS探针检测细胞内总活性氧(ROS)和线粒体活性氧(mtROS),JC-1探针检测线粒体膜电位、细胞内ATP水平,透射电镜检测线粒体结构,Western blotting检测Bcl-2、Bax蛋白表达。结果:与LPS组比较,LPS+槲皮素组的NRK-52细胞活力明显升高(P<0.05),细胞内ROS和mtROS水平显著降低(P<0.05),ATP水平上升(P<0.05),线粒体膜电位恢复,电镜观察下线粒体结构损伤减轻,细胞中促凋亡蛋白Bax表达水平显著降低(P<0.05);细胞中凋亡抑制蛋白Bcl-2蛋白表达水平明显升高(P<0.05)。结论:槲皮素能减轻LPS诱导肾小管上皮细胞损伤,其可能作用机制是通过恢复线粒体功能和抑制细胞凋亡信号通路的活化。

Objective:To investigate the protective effect of quercetin on lipopolysaccharide(LPS)-induced mitochondrial injury in rat renal tubular epithelial cells(NRK-52 E)and its effect on the apoptosis pathway.Methods:LPS-induced NRK-52 E was used to establish an in vitro model of sepsis kidney injury.The cells were divided into control group,LPS group,and LPS+quercetin group.The viability of NRK-52 E cells was detected by MTT colorimetry,the intracellular total ROS and mtROS were detected by DCFH-DA and MitoROS probes,the mitochondrial membrane potential and intracellular ATP level were detected by JC-1 probe,the mitochondrial structure was detected by transmission electron microscope,and the expression of Bcl-2 and Bax protein was detected by Western blotting.Results:Compared with the LPS group,the NRK-52 cell viability in the LPS+quercetin group was significantly increased(P<0.05),the total ROS in the cells and the mtROS levels were significantly reduced(P<0.05),and the ATP level increased(P<0.05);The mitochondrial membrane potential recovered.the mitochondrial structure damage was reduced under electron microscopy,and the expression of the pro-apoptotic protein Bax in the cell was significantly reduced(P<0.05);The expression of the apoptosis inhibitor Bcl-2 protein in the cell was increased(P<0.05).Conclusion:Quercetin can alleviate and the injury of renal tubular epithelial cells induced by LPS,and its possible mechanism is to restore mitochondrial function and inhibit the activation of apoptosis signal pathway.