RhoA激酶1在氧化低密度脂蛋白诱导足细胞损伤中的作用  

Role of ROCKI in the podocyte injury induced by oxidized low- density lipoprotein

作　　者：剧孟磊 王慧珍[1] 左洋洋 谢剑腾 文枫[2] 李盛[2] 付蕾[2] 李静[1] 梁田田[2] 汪延辉[1] 史伟[2] 王文健[1,2] 

机构地区：[1]南方医科大学研究生学院,广州510515 [2]广东省人民医院肾内科广东省医学科学院,广州510515

出　　处：《中华肾脏病杂志》2017年第1期37-42,共6页Chinese Journal of Nephrology

摘　　要：目的观察氧化低密度脂蛋白（ox-LDL）对小鼠肾小球足细胞RhoA激酶1（ROCKl）表达和活性的影响，并初步探讨ROCKl在ox-LDL诱导的足细胞损伤中的作用。方法体外培养小鼠条件永生性足细胞，以ox-LDL20μg／ml刺激足细胞24h，采用Western印迹法检测正常对照组、ox-LDL刺激组、ROCKl siRNA＋ox-LDL组以及ROCKl过表达（wtROCKl）＋OX。LDL组磷酸化肌球蛋白磷酸化亚单位（p-MYPT）、nephrin、LC3-I／、p62、磷酸化（P）．ULKl（ULKl是一种丝，苏氨酸氨酸激酶）的表达水平；Dil-ox-LDL与足细胞共孵育4h，荧光显微镜观察各组足细胞脂质的含量情况。结果与对照组相比，ox-LDL刺激增加足细胞ROCK活性，同时伴有nephrin、LC3-Ⅱ表达下降（P〈0．05），p62、p-ULKl表达上升（P〈0．05），细胞内胆固醇含量增加（P〈0．05）。增加ROCKl表达能进一步增加ox-LDL诱导的P-MYPT水平，并进一步降低nephrin、LC3-Ⅱ的表达，增加p62、P-ULKl的表达（P〈O．05）和细胞内胆固醇含量（P〈0．05）；与之相反，抑制ROCKl表达能抑制ox-LDL诱导的P-MYPT水平上调，同时上调nephrin、LC3-Ⅱ的表达（P〈0．05），下调p62、P-ULKl的表达（P〈0．05），降低细胞内胆固醇含量（P〈0．05）。结论ROCKl介导的脂质自噬障碍是ox-LDL诱导足细胞损伤的重要途径。Objective To explore the role of ROCK1 in oxidized low-density lipoprotein （ox- LDL） induced podocyte injury and its possible mechanism. Methods The conditionally immortalized mouse podocyte ceils were cultured in vitro and exposed to 20 μg/ml ox-LDL for 24 h. Western blotting was used to analyze the expression level of p-MYPT, nephrin, LC3- Ⅱ, p62, p-ULK1 in groups of control, ox-LDL, ROCK1 siRNA with ox-LDL, wtROCK1 with ox-LDL. Podocytes were incubated with DiI labeled ox- LDL for 4 h and fluorescence microscope was used to analyze lipid distribution. Results Compared with control group, ox-LDL increased cell cholesterol accumulation, activated ROCK along with decreased nephrin, LC3 - Ⅱ （P 〈 0.05）, and increased p62, and p - ULK1 expression （P 〈 0.05）. Over-expression of ROCK1 significantly decreased the expression of nephrin and LC3- 1I, but up- regulated the levels of p62, p- ULK1 and cell cholesterol accumulation in ox- LDL stimulated podocytes （P 〈 0.05）. In contrast, Inhibition of ROCK1 protected podocyte by improved lipophagy. Conclusion ROCK1 mediated disfunction of lipophagy contributes to the ox- LDL induced podocyte injury.

关 键 词：足细胞 脂蛋白类 LDL 自噬 RHO相关激酶类 LC3-Ⅱ 

分 类 号：R692[医药卫生—泌尿科学]