硫氧还蛋白2在2-乙酰氨基芴加肝切除诱导的卵圆细胞中的表达及意义

Change and Role of Thioredoxin 2 Expression in Oval Cells Induced with N-2-Acetylaminofluorene Diet and Partial Hepatectomy

目的观察硫氧还蛋白2(Trx2)在2-乙酰氨基芴(2-AAF)加肝切除诱导的卵圆细胞增殖中的表达,并探讨其表达的意义。方法Balb/c小鼠喂饲2-AAF加2/3肝切除方法诱导肝脏卵圆细胞的增殖。经门静脉灌注消化法和等密度离心法分离卵圆细胞,并在体外进行原代培养。免疫荧光和双标法对培养的细胞进行鉴定。免疫组化法检测卵圆细胞的增殖,免疫荧光法检测Trx2在卵圆细胞和肝实质细胞中的表达,TUNEL法检测卵圆细胞和肝实质细胞的凋亡。结果喂饲2-AAF后引起肝脏损伤,与肝切除前相比,肝切除后肝脏损伤明显加重(P<0.01),同时有明显的卵圆细胞增殖。卵圆细胞中Trx2的表达明显高于肝实质细胞,同时其凋亡率明显低于肝实质细胞(P<0.01)。结论喂饲2-AAF加2/3肝切除可以引起严重的肝损伤,促进卵圆细胞增殖,卵圆细胞高表达Trx2可以抑制自身凋亡和损伤,在肝脏功能的恢复过程中起着非常重要的作用。

Objective To investigate the change and role of thioredoxin （Trx） 2 expression in oval cells induced with N-2-acetylaminofluorene （2-AAF） diet and partial hepatectomy. Methods Oval cell response was stimulated in Balb/c mice by treatment with 2-AAF diet and partial hepatectomy. A modification of two-step perfusion protocol and isopycnic centrifugation were used to isolate oval cells from liver. Primary oval cells were cutured in LE medium in vitro. Immunofluorescence and double-fluorescence immunostaining were used for characterization of oval ceils. Immunohistochemistry was used to detect the proliferation in oval cells. Immunofluorescence was used to detect Trx2 expression in oval cells and parenchymal cells, TUNEL method in situ was used to detect apoptosis of them. Results Compared with the levels of ALT and AST before partial hepatectomy, the levels were higher after operation （P〈0.01）, this indicates that partial hepatectomy induced severe liver injury. Trx2 expression in oval cells was significantly higher than that in parenchymal cells （P〈0.01）. Apoptotic ratio of parenchymal cells was significantly higher than that of oval cells （P〈0.01）. Conclusion 2-AAF diet and partial hepatectomy can induce severe liver injury, which can induce the proliferation of oval cells for compensation of liver function. Overexpression of Trx2 can inhibit apoptosis and injury of oval cells by treatment with 2-AAF diet and partial hepatectomy, it plays an important role to recover the liver function.