IGFBPrP1与硫代乙酰胺对小鼠肝组织的影响及其机制

Effects of IGFBPrP1 and thioacetamide on liver tissues in mice

目的:通过对胰岛素样生长因子结合蛋白相关蛋白1(IGFBPrP1)与硫代乙酰胺(TAA)对小鼠肝组织影响的研究,明确IGFBPrP1在肝纤维化中的作用及其机制。方法:清洁级C57BL/6野生型小鼠32只,随机分为4组:正常对照组、重组小鼠IGFBPrP1(rmIGFBPrP1)4周组、TAA2周组及TAA4周组,每组8只。取肝组织行HE、苦味酸-天狼星红及免疫组织化学染色和Westernblotting检测。结果:rmIGFBPrP14周组肝细胞广泛脂肪变性,TAA2周组出现纤维组织增生,TAA4周组病理改变较TAA2周组严重。与正常对照组相比,rmIGFBPrP14周组、TAA2周组和TAA4周组IGFBPrP1、转化生长因子β1(TGF-β1)、Smad3、p-Smad2/3、Ⅲ型胶原(ColⅢ)、I型胶原(ColⅠ)、纤维连接蛋白(FN)的表达增高(P<0.05)。rmIGFBPrP14周组IGFBPrP1、ColⅠ和FN的表达与TAA2周组无显著差异。结论:IGFBPrP1在TAA诱导的肝纤维化形成过程中发挥重要作用,并可作为独立致病因子引起小鼠肝组织中细胞外基质生成增多,且该作用是通过TGF-β1/Smad3信号通路来实现的。

AIM:To investigate the effects of insulin-like growth factor binding protein related protein 1(IGFBPrP1)and thioacetamide(TAA)on the liver tissues,and to identify the role of IGFBPrP1 in liver fibrosis.METHODS:Thirty-two male C57BL/6 wild-type mice were randomly divided into 4 groups(n=8 in each group):control group,recombinant murine IGFBPrP1(rmIGFBPrP1)4 weeks group,TAA 2 weeks group and TAA 4 weeks group.The methods of hematoxylin-eosin(HE)staining,picric acid-Sirius red staining,immunohistochemistry and Western blotting were performed.RESULTS:The extensive fatty degeneration of liver cells in rmIGFBPrP1 4 weeks group was observed.The collagen deposition was found in TAA 2 weeks group.In TAA 4 weeks group,the degree of hepatic fibrosis was more serious than that in TAA 2 weeks group.The expression levels of IGFBPrP1,transforming growth factor beta 1(TGF-β1),Smad3,p-Smad2/3,collagen Ⅲ,collagenⅠand fibronectin(FN)in liver tissues were higher in rmIGFBPrP1 4 weeks group,TAA 2 weeks group and TAA 4 weeks group than those in control group.No significant difference of the expression levels of IGFBPrP1,collagen I and FN between rmIGFBPrP1 4 weeks group and TAA 2 weeks group was observed.CONCLUSION:IGFBPrP1 plays an important role in the process of thioacetamide-induced liver fibrosis.Meanwhile,IGFBPrP1 induces excessive deposition of extracellular matrix through TGF-β1/Smad3 pathway.