Kupffer细胞表达的Fas配体在急性胰腺炎并发肝损伤中的作用

Role of Kupffer cell-expressed Fas ligand on acute pancreatitis-associated liver injury

目的探讨Kupffer细胞表达的Fas配体(FasL)对急性胰腺炎(AP)肝损伤的介导作用以及Kupffer细胞抑制剂氯化钆(GdCl3)对肝损伤的保护作用。方法ICR小鼠54只,采用随机数字法将其分为对照组(6只)、AP组(24只)和GdCl3预处理+AP组(24只),后两组再分为4个时间点(每个时间点6只)。用雨蛙素诱导制作小鼠AP模型;用自动生化仪检测血清ALT、AST、LDH和淀粉酶(AMY)水平;用ELISA试剂盒检测血清FasL水平,用Western blotting法检测肝脏FasL蛋白的表达情况。结果AP时血清AST、ALT、LDH、AMY水平及肝脏FasL蛋白表达明显升高,AP组4、8、16和24h时血清FasL浓度(505.94±36.21,496.60±33.65,476.64±22.66,450.75±38.21)显著高于对照组(83.60±7.75,P<0.01);用GdCl3预处理后,在AP发生后升高的血清AST、ALT、LDH、AMY水平明显降低,肝脏FasL蛋白表达显著下调。GdCl3预处理组4、8、16h和24h时血清FasL浓度(211.37±24.86,190.41±20.36,200.49±32.03,178.60±7.93)显著低于AP组相应时点的浓度(P<0.01)。结论AP通过上调Kupffer细胞表达的FasL介导肝损伤,GdCl3通过抑制FasL的表达对AP肝损伤发挥保护作用。

Objective To explore the role of Kupffer cell-expressed Fas ligand （FasL） on acute pancreatitis （AP）, and the protective effect of gadolinium chloride （GdCl3）, a Kupffer cell inhibitor, on liver injury during AP. Methods Fifty-four ICR mice were randomly assigned into three groups： healthy control group （n=6）; AP group （four time points for observation, 6 mice each）; Gd＋AP group （GdCl3 pretreatment group, four time points for observation, 6 mice each）. AP was induced in mice using cerulein. Liver parenchymal enzymes （AST, ALT and LDH） and amylase （AMY） were assayed using an automatic analyzer. Serum FasL was assayed with ELISA and FasL protein expression in liver was assayed by Western blotting. Results After induction of AP in mice, the serum levels of AST, ALT, LDH, AMY and liver FasL expression were significantly elevated. Serum FasL levels at 4, 8, 16 and 24h after AP induction were 505. 94 ±36. 21,496. 60±33. 65,476. 6±22. 66 and 450. 75±38. 21, respectively, which were significantly higher than those in healthy control group （83. 60±7. 75, P〈0. 01）. Elevated serum levels of AST, ALT, LDH, AMY and liver FasL expression in AP mice were attenuated by pretreatment with GdCl3. After pretreatmem with GdCl3 in AP mice, the level of FasL at 4, 8, 16 and 24h after AP induction was 211. 37±24. 86,190. 41±20. 36,200. 49±32. 03 and 178. 60±7, 93, respectively, and they were significantly lower compared with those at the corresponding time point in AP group （P〈0. 01）. Conclusion AP may induce liver injury by up-regulating Kupffer cell-derived FasL. GdCl3 may prevent liver from acute pancreatitis-associated injury via inhibiting the expression of FasL.