线粒体未折叠蛋白反应在棕榈酸诱导肾小管上皮细胞脂质聚集中的作用  

The role of mitochondrial unfolded protein response in palmitic acid-induced lipid accumulation in renal tubule epithelium in vitro

作　　者：温睿智 杜晓刚[1] WEN Ruizhi;DU Xiaogang(Department of Nephrology,the First Affiliated Hospital of Chongqing Medical University,Chongqing 400042,China)

机构地区：[1]重庆医科大学附属第一医院肾内科,重庆400042

出　　处：《西安交通大学学报（医学版）》2024年第3期419-427,共9页Journal of Xi’an Jiaotong University（Medical Sciences）

摘　　要：目的探讨线粒体未折叠蛋白反应(mitochondrial unfolded protein reaction,UPR^(mt))对肾小管上皮细胞(human kidney 2,HK-2)脂代谢的影响。方法采用棕榈酸(palmitic acid,PA)诱导HK-2细胞内脂质聚集,分别予siRNA抑制UPR^(mt)或巴多索隆(the 2-cyano-3,12-dioxooleana-1,9-dien-28-oic acid,CDDO)增强UPR^(mt)。油红染色观察细胞内脂质聚集情况,线粒体膜电位检测试剂盒(JC-1)测定线粒体膜电位(mitochondrial membrane potential,MMP),Mito-SOX测定线粒体内活性氧(reactive oxygen species,ROS)含量,Western blotting检测HSP60、LONP1、CLPP、ACOX1、PPARα、PGC1α、CPT1α蛋白表达。结果PA诱导HK-2细胞脂质聚集、MMP降低、ROS产生增多及UPR^(mt)关键蛋白HSP60、LONP1表达降低;抑制UPR^(mt)可加剧PA导致的脂质聚集、MMP降低、ROS产生增多,HSP60、LONP1表达进一步降低;增强UPR^(mt)可缓解PA导致的脂质聚集、MMP降低、ROS产生增多以及HSP60、LONP1表达降低。结论PA诱导的HK-2细胞脂质聚集可能与线粒体功能障碍有关,UPR^(mt)在该过程中对HK-2细胞具有保护作用。Objective To investigate the effect of mitochondrial unfolded protein response(UPR^(mt))on lipid metabolism in human kidney 2(HK-2)cells.Methods Lipid accumulation was induced by palmitic acid(PA)in HK-2 cells.The cells were pretreated with siRNA or CDDO respectively.The intracellular lipid accumulation was observed by oil red staining;mitochondrial membrane potential(MMP)was measured by JC-1.The contents of reactive oxygen species(ROS)in mitochondria were measured by Mito-SOX,and the expressions of HSP60,LONP1,CLPP,ACOX1,PPARα,PGC1αand CPT1αwere detected by Western blotting.Results PA induced lipid aggregation,MMP decrease,ROS generation in mitochondria and the decreased expression of UPR^(mt)proteins(e.g.,HSP60 and LONP1)in HK-2 cells.Pretreatment of HK-2 cells with siRNA could aggravate lipid aggregation,MMP decrease and ROS generation induced by PA,and further decrease the expression of HSP 60and LONP1.Pretreatment of HK-2 cells with CDDO alleviated lipid aggregation,MMP decrease,ROS generation and decreased HSP60 and LONP1 expressions induced by PA.Conclusion Lipid aggregation in HK-2 cells induced by PA may be related to mitochondrial dysfunction and UPR^(mt)has a protective effect on HK-2 cells in the process.

关 键 词：线粒体未折叠蛋白反应(UPR^(mt)) 棕榈酸(PA) 肾小管上皮细胞(HK-2) 脂质聚集 活性氧(ROS) 

分 类 号：R58[医药卫生—内分泌]