【摘要】 目的:探讨Toll样受体4(TLR4)在高血压肾损害中的作用机制以及福辛普利(fosinopril,Fos)、氯沙坦(losartan,Los)的肾脏保护机制。方法:将大鼠肾小管上皮细胞(NRK-52E)分5组:正常对照组、NRK-52E+AngⅡ组、NRK-52E+AngⅡ+Fos(10-5mmol/L)组、NRK-52E+AngⅡ+Los(10-5mmol/L)组、NRK-52E+AngⅡ+Fos(10-5mmol/L)+Los(10-5mmol/L)组,培养24 h进行检测;同时建立稳定转染TLR4-specific RNAi质粒的NRK-52E细胞株。RT-PCR检测TLR4,IL-6,TNF-αmRNA表达;Western印迹检测TLR4蛋白表达;免疫细胞化学方法观察NF-κB核易位情况;酶联免疫吸附法(ELISA)检测上清IL-6及TNF-α水平。结果:AngⅡ可上调TLR4,IL-6,TNF-α的表达水平,诱导NF-κB核易位活化(P<0.01);TLR4-specific RNA干扰后NRK-52E中TLR4水平显著下降(P<0.01),AngⅡ刺激转染后的NRK-52E,其TLR4,IL-6,TNF-α水平较NRK-52E+AngⅡ组显著下降(P<0.01),NF-κB核活化水平无明显变化(P>0.05)。Fos或/和Los干预后可明显下调TLR4,IL-6,TNF-α表达,显著抑制NF-κB活化(P<0.01或P<0.05),联合用药与单药组无统计学差异(P>0.05)。结论:TLR4在高血压肾损伤中可能有致炎作用。Fos和Los治疗高血压肾损害的作用机制之一,可能是通过下调TLR4基因及相关炎症介质的表达。更多还原

【Abstract】 Objective To determine the mechanism of Toll-like receptor 4(TLR4) in hypertensive renal injury and the protective effect of fosinopril(Fos) and losartan(Los).Methods NRK-52E was incubated into 5 groups: NRK-52E(normal control),NRK-52E+AngⅡ,NRK-52E+AngⅡ+Fos(10-5 mmol/L),and NRK-52E+AngⅡ+Los(10-5 mmol/L),NRK-52E +AngⅡ+Fos(10-5 mmol/L)+Los(10-5 mmol/L).TLR4-specific RNAi plasmids were stably transfected into NRK-52E.After 24 h,TLR4,IL-6,and TNF-α mRNAs were examined by reverse transcription-polymerase chain reaction(RT-PCR).TLR4 proteins were detected by Western blot,NF-κB nuclear translocations were tested by immunocytochemistry,and IL-6 and TNF-α supernatant levels were tested by enzyme linked immuno-sorbent assay(ELISA).Results TLR4,NF-κB,IL-6,and TNF-α were highly expressed in AngⅡ induced NRK-52E(P<0.01).In NRK-52E that was stably transfected TLR4-special RNAi plamids,TLR4 protein and mRNA expression were obviously inhibited(P<0.05).After stimulation by AngⅡ,the TLR4,IL-6,TNF-α levels in the stabe transfection group were increased compared with the normal group(P<0.05).Fos or/and Los down-regulated TLR4,IL-6,and TNF-α expressions(P<0.05),but no cooperation was observed.Conclusion TLR4 may lead to inflammatory reaction in hypertensive renal injury.Fos or/and Los can decrease the expressions of TLR4 and correlate inflammatory factors,which may be part of the renal protective mechanism.更多还原