凝血酶敏感蛋白-1介导脓毒症肝损伤中ERK通路的作用研究

目的观察凝血酶敏感蛋白-1(TSP-1)介导的脓毒症肝损伤中细胞外调节激酶(ERK)通路的作用.方法选用雄性Balb/c小鼠随机分为4组(n=5):假手术(sham)组、CLP对照组、阴性片段对照组、有效片段组.利用流体尾静脉注射法予以TSP-1特异性的siRNA片段进行RNA干扰(RNA)i,下调肝脏TSP-1表达,采用盲肠结扎穿刺(CLP)制作脓毒症模型,检测肝脏TSP-1表达变化,检测血清转氨酶和TNF-α含量,检测肝脏ERK蛋白表达变化.结果有效片段组中肝脏TSP-1的表达明显下调,验证RNAi有效.与假手术组相比,CLP组和阴性对照组转氨酶ALT和AST含量、TNF-α含量明显升高(P<0.05),磷酸化ERK蛋白表达明显降低(P<0.05),予以有效片段进行RNAi后,ALT和AST含量、TNF-α含量明显降低(P<0.05),磷酸化ERK蛋白表达明显升高(P<0.05).结论 TSP-1参与介导脓毒症肝损伤,导致血清转氨酶及TNF-α含量升高,ERK通路的抑制是其分子机制之一.

Role of ERK Pathway in Septic Liver Injury Induced by Thrombospondin-1

Objective To observe the role of extracellular regulated protein kinases(ERK)pathway in septic liver injury induced by the thrombospondin-1(TSP-1).Methods Male Balb/c mice were randomly divided into four groups(n=5 per group):sham,CLP control,siRNA negative fragment control,and siRNA effective fragment group.TSP-1 protein expression in liver was downregulated by hydrodynamic tail vein injection of the fragments of siRNA specific for TSP-1.The model for sepsis was developed by cecal ligation and puncture(CLP).TSP-1 expression in liver was detected.Serum aminotransferase and serum TNF-α contents were detected.The change of liver ERK protein was detected.Results In siRNA effective fragment group,the expression of TSP-1 in liver was obviously decreased.This confirmed that RNAi effectively downregulated the expression of TSP-1.In comparison with sham group,serum ALT,AST and TNF-α contents were significantly increased as well as the expression of liver phospho-ERK was decreased in CLP and siRNA negative fragment groups.After RNAi,all detection results were inverse.Conclusions TSP-1 may induce septic liver injury.This results in increased serum aminotransferase and serum TNF-α contents.The suppression of ERK pathway is one of the molecular mechanisms.