摘要
目的通过siRNA（RNAi）干扰选择性下调TLR4基因的表达，探讨高糖对大鼠肾小管上皮细胞（NRK．52E）T0ll样受体4（toll－like receptor4，TLR4）及其转接子髓分化因子88（myeloid differentiation factor88，MyD88）和炎性因子分泌的影响。方法设计并合成3对针对大鼠TLR4基因的特异性siRNA片段，以带有红色荧光的BLOCK—ITAlexaFluor作为阴性对照，荧光显微镜下观察细胞转染效率，实时定量PCR检测TLR4mRNA的表达变化。挑选基因沉默效率最佳的siRNA用于进一步实验，细胞被分5组：（1）正常糖对照组（NG）；（2）高糖组（HG）；（3）HG＋血管紧张素Ⅱ（AngII）＋空转组；（4）HG＋AngⅡ＋siRNA组；（5）HG＋AngⅡ＋厄贝沙坦（IrB）组。采用实时定量PCR法检测TLR4、MyD88mRNA的表达，Western印迹检测TLR4、MyD88及核因子kappaB（NF-kB）蛋白表达；ELISA法检测巨噬细胞趋化蛋白1（MCP-1）、白细胞介素6（IL-6）的表达。结果与NG组比较，高糖组TLR4／MyD88mRNA及TLR4、MyD88、NF-kB蛋白表达水平明显上调（均P〈0．01），细胞上清MCP-1、IL-6水平亦升高（P〈0．01）；空转组与高糖组比较差异无统计学意义（P〉0．05）；SiRNA组、ARB组TLR4、MyD88mRNA明显下调，TLR4、MyD88及NF-kB蛋白明显下调，MCP-1、IL-6表达亦下调（均P〈0．01）。结论高糖上调小管上皮细胞TLR4／MyD88信号及炎性细胞因子表达，Ang11可增强此效应；特异性基因沉默可阻断由高糖及AngII诱导的TLR4信号通路的激活，并下调炎性介质的释放；TLR4信号通路在高糖、高肾素环境肾小管上皮细胞炎性反应机制中发挥关键作用。
Objective To observe the expression of toll like receptor 4（TLR4） Signaling and the release of inflammation factors in rat tubular epithelial cell（NRK-52E） under high glucose condition after TLR4- siRNA transfection. Methods Three TLR4- siRNA sequences were designed and synthesized. The transfection efficiency was observed by fluorescence microscope after transfection, and the expression of TLR4 mRNA was detected by real time PCR. The most effective siRNA was selected to be used for forward experiments. After transfection for 24 h, cells were stimulated with 25 mmol/L glucose and/or 10-7 mmol/L Angiotension ]] （Ang ]I ） for 12 h, 24 h; cells without stimulation were as normal control. Real- time PCR was used to analyze TLR4 and myeloid differentiation factor 88
出处
《中华肾脏病杂志》
CAS
CSCD
北大核心
2013年第11期837-841,共5页
Chinese Journal of Nephrology
基金
国家自然科学基金项目（81060063）
江西省教育厅科学基金项目（JJJ11354）
