TGF-β1在肝再生调控中的作用研究

目的 探讨70%肝部分切除后TGF-β1在肝再生调控中的作用.方法 MTT方法 检测TGF-β1对原代肝细胞的作用;建立70%肝部分切除(PH)模型,收集切除后2d的血清,用MTT方法 检测其对IG12细胞的促增殖作用,并用免疫细胞化学方法 观察其对IG12细胞TGFβ1表达的影响;用免疫组织化学和Western blot检测再生肝组织中TGF-β1的表达.结果 TGF-β1能抑制原代肝细胞增殖;PH后大鼠血清不仅对IG12细胞有明显的促增殖作用,还能提高IG12细胞TGF-β1的表达;免疫组化结果 显示大鼠PH后肝细胞TGF-β1表达逐渐下降,至第3天呈阴性结果 ,而后升高,直至再生结束时稳定在正常肝脏表达水平,Western blot显示PH后再生早期TGF-β1表达暂时升高,12 h达到高峰,第1天开始下降,第3天降至最低点,5d开始逐渐升高,至第7天恢复到正常水平.结论 TGF-β1明显抑制肝细胞增殖,在PH后肝再生过程中,肝组织中TGF-β1表达明显下降,有助于肝再生的完成.

Role of TGF-β1 in modulation of hepatic regeneration

Objective To investigate the role of TGF-β1 in regulation of liver regeneration after partial hepatectomy(PH).Methods The effect of TGF-β1 on the proliferation of primary hepatocytes was observed by MTT assay.The animal model of partial hepatectomy(PH)in rats was established.Serum collected from rats receiving partial hepatectomy could be used to stimulate the proliferation of IG12 and the expression of TGF-β1 in IG12 cells which could be detected by immuocytochemistry.The TGF-β1 expression characteristics of hepatocytes after PH were detected by immunohistochemistry and western blot.Results TGF-β1 could significantly arrest the proliferation of primary hepatocytes.Rat serum collected after PH could promote the proliferation of IG12,the result of MTT assay showed that the value of both 25ul group(A=1.109±0.033)and 15ul group(A=1.073±0.051)were higher than control (A=0.732±0.053,P＜0.05).Meanwhile,IG12 cells were stimulated by rat serum after PH,which showed a high expression of TGF-β1 by immunocytochemical assay.Immunohistochemical staining showed that TGF-β1 expression in hepatocytes of regenerated liver was decreased after PH,and then turned to be negative 3 day after PH.After liver regeneration accomplished,TGF-β1 positive signals was found again in hepatocytes.The same results were found by western blot assay.Conclusion TGF-β1 could significantly arrest the proliferation of primary hepatocytes.During the process of liver regeneration,the expression of TGF-β1 is gradually decreased,which is beneficial for the liver regeneration.