凝血酶敏感蛋白-1对脓毒症肝损伤影响的实验研究

Experimental Study on Impact of Thrombospondin-1 on Septic Liver Injury

目的利用RNA干扰(RNA)i方法探讨凝血酶敏感蛋白-1(TSP-1)对脓毒症肝损伤的影响及机制.方法选用雄性Balb/c小鼠随机分为4组(n=10):假手术组(sham)、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RNAi,下调肝脏TSP-1表达,采用盲肠结扎穿刺(CLP)制作脓毒症模型,检测血清转氨酶、血清TNF-α含量,观察肝细胞凋亡,检测肝脏JNK蛋白表达变化.结果与假手术组相比,CLP组和阴性对照组转氨酶ALT和AST含量、TNF-α含量、凋亡细胞比例明显升高(P<0.05),磷酸化JNK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、凋亡细胞比例明显降低(P<0.05),磷酸化JNK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,导致血清转氨酶及血清TNF-α含量升高、肝细胞凋亡增加,其机制与JNK通路的抑制有关.

Objective To explore the impact and mechanism of the thrombospondin-1 in septic liver injury by application of RNA interference.Methods Male Balb/c mice were randomly divided to four groups(n=10 per group):sham,CLP control,siRNA negative fragment control,and siRNA effective fragment group.Through hydrodynamic tail vein injection,the fragments of siRNA specific for TSP-1 were deliveried to make RNA interference and reduce TSP-1 protein expression.The model for sepsis was developed by cecal ligation and puncture(CLP).Serum aminotransferase and serum TNF-α contents were detected.Apoptosis of liver cell was observed.The change of liver c-Jun N-terminal kinase(JNK)was detected.Results In comparison with sham group,serum ALT,AST and TNF-α contents,apoptosis of liver cell were significantly increased as well as the expression of liver phospho-JNK was decreased in CLP and siRNA negative fragment groups.After RNAi all detections were inverse.Conclusions TSP-1 may induce septic liver injury.This results in increased serum aminotransferase,serum TNF-α contents and increased apoptosis of liver cell.The suppression of phospho-JNK is involved in the mechanism.