PPARγ激动剂对RSV感染的A549细胞TLR3、TNF-α表达的抑制作用

Inhibitory effect of PPARγ agonists on TLR3 and TNF-α expression in human lung epithelial cells infected with respiratory syncytial virus

目的 探讨 A549细胞呼吸道合胞病毒（RSV）感染后Toll样受体3（TLR3）及肿瘤坏死因子-α（TNF-α） mRNA和蛋白表达及PPARγ激动剂15-脱氧前列腺素J2（15d-PGJ2）和罗格列酮的干预作用.方法 建立RSV感染的细胞模型,将传代培养的细胞随机分成6组：15d-PGJ2干预组（A）、罗格列酮干预组（B）、RSV组（C）、PDTC组（D）、GW9662组（E）及对照组（F）.各组在培养12、24和48 h后收获上清液和细胞,实时荧光RT-PCR检测TLR3和TNF-α mRNA表达,Western Blot检测TLR3蛋白表达,ELISA法检测上清中TNF-α蛋白水平.结果 与F组相比,各时间点C组TLR3和TNF-α mRNA及蛋白表达均明显升高（均P＜0.01）;与C组相比,A组、B组和D组TLR3和TNF-α mRNA及蛋白表达均明显降低（均P＜0.01）.15d-PGJ2和罗格列酮对TLR3和TNF-α mRNA和蛋白表达的抑制作用在12 h最明显;同一时间点A组和B组TLR3和TNF-α mRNA和蛋白的表达量均呈剂量依赖性下降.结论 RSV感染后TLR3和TNF-α mRNA及蛋白表达升高;罗格列酮和15d-PGJ2能以剂量依赖性方式抑制TLR3和TNF-α mRNA和蛋白表达.

Objective To study the change of toll-like receptor 3 （TLR3） and tumor necrosis factoralpha （TNF-α） both at the levels of protein and mRNA in human lung epithelial cells （A549） infected with respiratory syncytial virus （RSV） and the effects of peroxisome proliferator-activated receptor γ （PPARγ） agonists Rosiglitazone and 15-deoxy-delta12,14 prostaglandin J2 （15d-PGJ2）.Methods RSV inoculation after A549 cells subcultured,then A549 cells were randomly divided into six groups：15d-PGJ2 ＋ RSV group （group A）,Rosiglitazone ＋ RSV group （group B）,RSV group （group C）,PDTC ＋ RSV group （group D）,GW9662 ＋ Rosiglitazone ＋ RSV group （group E） and cell control group （group F）.Cells were harvested after incubated for 12 h,24 h and 48 h respectively.The expression of TLR3 and TNF-α at mRNA was determined by real-time RT-PCR,and the protein level of TLR3 and TNF-α was determined by Western Blot and ELISA respectively.Results The expression of TLR3 and TNF-α at mRNA and protein at virous time in group C were significantly higher than those of group F （all P 〈 0.01）.While,the expression of TLR3 and TNF-α mRNA and protein in group A,B and D were significantly lower than than those of group C （all P 〈 0.01）.15d-PGJ2 and Rosiglitazone had the strongest effect to inhibit the expression of TLR3 and TNF-αmRNA and protein at 12 h and the expression of TLR3 and TNF-α mRNA and protein decreased as the increasing dose of 15d-PGJ2 and Rosiglitazone.Conclusion RSV infection induces increased expression of TLR3 and TNF-α mRNA and protein,which can be inhibited by Rosiglitazone and 15d-PGJ2 in a dose-dependent manner.