白细胞介素1β对肾小管上皮细胞过氧化物酶体增殖蛋白激活性受体γ及辅调节因子表达的影响  

lnterleukin 1 β regulates the expression of peroxisome proliferator-activated receptor γ and its coregulators in renal tubular cells

作　　者：靳远萌[1] 陈慧[1] 朱冰冰[1] 韩琳[1] 王伟铭[1] 陈楠[1] 

机构地区：[1]上海交通大学医学院附属瑞金医院肾脏科,200025

出　　处：《中华肾脏病杂志》2009年第4期282-287,共6页Chinese Journal of Nephrology

基　　金：国家自然科学基金（30270613,30771000）;上海市重点学科（T0201）;上海市卫生局重点学科基金（05Ⅲ001）;上海市卫生局重点课题（2003ZD002）

摘　　要：目的探讨白细胞介素1β（1L-1β）介导的炎性反应中过氧化物酶体增殖蛋白激活性受体γ（PPAR-γ）及其辅调节因子的表达变化，分析其相互作用机制。方法体外培养人肾小管上皮细胞（HK-2），应用IL-1β作用于HK-2细胞，收集细胞总mRNA、胞核蛋白和细胞培养上清液。应用实时定量PCR、Western印迹法、ELISA法、凝胶电泳迁移率实验（EMSA）法分别从mRNA水平、蛋白质水平、DNA结合活性水平检测PPARγ及其辅调节因子（包括辅激活因子和辅抑制因子）和单核细胞趋化蛋白1（MCP-1）的表达变化。结果不同浓度的IL-1β（0～20μg／L）刺激24h后，PPARγ、辅激活因子SRC-1、SRC-2和PGC-1 mRNA表达水平均呈总体下调趋势（P〈0．05），同时辅抑制因子NCoR呈显著上调趋势（P〈0．05）。以10μg／L作为IL-1β最佳刺激浓度，SRC-2和PGC-1的mRNA水平在刺激1h后就分别显著下调了57％（P〈0．01）和48％（P〈0．01）；SRC-1的mRNA水平在刺激2h后显著下调了43％（P〈0．05），而PPARγ在刺激4h时下调了55％（P〈0．01）；NCoR在刺激8h后出现显著上调（为对照组的2．17倍，P〈0．05），之后又缓慢下降，至24h仍高于对照组，但差异无统计学意义。Western印迹结果显示，PPARγ的蛋白表达在IL-1β（10μg／L）刺激4h后出现显著下降。ELISA结果显示MCP-1的分泌水平呈持续增高，8h后达到最高值[（160．56±2．8）ng／L，P〈0．011，至24h仍为（50．82±1．25）ng／L（P〈0．01）。EMSA结果显示PPARγ的DNA结合活性呈总体减弱趋势，至24h达到最低值，而NF—κB的DNA结合活性均呈总体增强趋势，至24h达到高峰。结论在肾脏炎性反应进程中，IL-1β诱导的NF—κB炎性通路激活可引起PPARγ及辅激活因子的表达下调，MCP-1和辅抑制因子的表达上调。不仅PPARγ，其辅调节因子也积极参与肾脏炎性反应。Objective To investigate the changes of expression of peroxisome proliferator-activated receptor γ （PPARγ） and its coregulators and monocyte chemotactic factor （MCP-1） treated with interleukin-1β （IL-1β）, and to analyze the mechanism of interaction of these factors. Methods Renal tubular cells （HK-2 cells） were cultured in vitro. Total cellular RNA was isolated for real-time quantitative polymerase chain reaction （real-time PCR）, nuclear extracts were prepared for Western blot analysis and EMSA. The supernatant was collected for ELISA after the treatment of IL-1β at different concentrations and time points. Results Under stimulus of different concentrations of IL-1β （0-20 μg/L） for 24 hours, the mRNA expression of PPARγ, SRC-1, SRC-2 and PGC-1 decreased significantly （P〈0.05）, meanwhile NCoR increased obviously （P〈0.05）. In further time-dependent experiment, the mRNA levels of SRC-2 and PGC-1 decreased by 57% and 48%, respectively, at 1 hour after treatment with 10 μg/L IL-1β （P〈0.05）. The expression of SRC-1 decreased by 43%only after 2 hours （P〈0.05）. The expression of NCoR was not obviously changed until stimulated by IL-1β for 8 hours （2.17 folds, P〈0.05）, then it decreased slowly. In the same time-dependent experiment, Western blot analysis showed that IL-1β（10 μg/L） significantly decreased the protein level of PPARγ at 4 hours （P〈0.05）. ELISA analysis revealed that the secretion of MCP-1 kept on rising and reached the peak （160.56±2.80） ng/L at 8 hours （P〈0.01）, then decreased to （50.82±1.25） ng/L at 24 hours （P〈0.01）. IL-1β could down- regulate the DNA binding activity of PPARγ, and the activity of NF-κB was up-regulated. Conclusions PPARγ and its coregulators are closely related to MCP-1 and NF-κB during inflammation response in kidney. The activation of NF-κB by IL-1β leads to the decrease of PPARγ and its coaetivators expression levels, however the expression of MCP-1 and NCoR in renal tubular epi

关 键 词：白细胞介素1 PPARΓ 单核细胞化学吸引蛋白质1 NF—κB 辅调节因子 

分 类 号：R692.6[医药卫生—泌尿科学]