纤溶系统对罗格列酮治疗肺纤维化的影响及信号机制

Rosiglitazone in treatment of lung fibrosis through activation fibrinolysis system and ERK signal pathway

目的探讨纤溶酶原激活物抑制剂1(plasminogen activator inhibitor-1,PAI-1)对罗格列酮抑制成纤维细胞转化的影响及信号机制。方法大鼠胚肺成纤维细胞随机分为3组:罗格列酮组、PAI-1组、对照组。罗格列酮组加入罗格列酮30mmol/L,PAI-1组加入罗格列酮30mmol/L及PAI-1 20mmol/L,对照组加入培养基。分别于24、48、72h收取细胞冻存。采用反转录聚合酶链反应(reverse transcription-polymerase chain reaction,RTPCR)法检测成纤维细胞24hPAI-1和α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)mRNA的表达;Western Blot方法分析3个时间点丝氨酸/苏氨酸蛋白激酶(serine/threonine kinase,AKT)、细胞外调节蛋白激酶(extracellular regulated protein kinases,ERK)的蛋白表达。结果罗格列酮抑制成纤维细胞PAI-1mRNA、α-SMA mRNA及ERK的蛋白表达,与对照组比较差异有统计学意义(P<0.05);上调成纤维细胞内PAI-1表达后,罗格列酮对PAI-1、α-SMA的基因表达及3个时间点ERK蛋白表达的抑制作用均减弱,与罗格列酮组比较差异有统计学意义(P<0.05);罗格列酮对AKT蛋白表达无抑制作用(P>0.05)。结论罗格列酮通过抑制大鼠成纤维细胞PAI-1的表达活化纤溶系统;上调PAI-1表达可以使罗格列酮抑制成纤维细胞转化的能力减弱,这种作用可能是通过PAI-1与ERK信号途径之间的相互作用实现的。

Objective To investigate the effect of plasminogen activator inhibitor-1（PAI-1）in rosiglitazone inhibition the transformation of fibroblasts and the signal mechanism in the process.Methods The fibroblasts from rats＇ embryo lung tissues were divided into three groups：rosiglitazone,PAI-1and control groups.The fibroblasts in rosiglitazone group were added with 30mmol/L rosiglitazone,the fibroblasts in PAI-1group were added with 30 mmol/L rosiglitazone and 20 mmol/L extrinsic PAI-1,and the amount of culture medium was added in the control group.The fibroblasts were collected at 24 h,48 h and 72 h,and were storaged at frozen condition.The mRNA expression of PAI-1andα-SMA at 24 h were determined by reverse transcription-polymerase chain reaction（RT-PCR）.Western Blot analysis was used to determine the expression of serine/threonine kinase（AKT）and extracellular regulated protein kinases（ERK）at 24 h,48hand 72 h.Results Rosiglitazone inhibited PAI-1mRNA,α-SMA mRNA and ERK protein expression of fibroblasts,and there were significant difference in rosiglitazone group compared with control group（P0.05）.The inhibition effect was alleviated by up-regulation PAI-1expression of fibroblasts,there was significant difference in PAI-1group compared with rosiglitazone group（P0.05）.The expression of AKT showed no difference among three groups（P0.05）.Conclusion Rosiglitazone inhibits the transformation of lung fibroblasts through inhibition on the expression of PAI-1that activates fibrinolytic system and through the cross-talk between PAI-1and ERK signal pathway.