双歧杆菌对幼鼠肝缺血再灌注损伤保护作用的实验研究

The experimental study on the protective effects of bifidobacterium against hepatic ischemia-repefusion injury in immature rats

目的研究双歧杆菌对幼鼠肝缺血再灌注损伤的保护作用并探讨相关机制。方法 90只SD幼鼠随机分为3组:对照组、模型组和治疗组。采用阻断肝动脉和门静脉45 min后再灌注12 h建立幼鼠肝缺血再灌注模型。Henry速率法检测各组大鼠血清中ALT和AST的变化,HE染色观察肝组织病理学改变,ELISA法检测肝组织TNF-α以及IL-6,采用改良鲎试验测定血浆内毒素,免疫组织化学染色检测肠黏膜occludin分布。结果双歧杆菌治疗组的血清ALT及AST表达显著低于模型组。同时,组织切片显示,肝细胞坏死程度也显著减轻。与模型组相比,双歧杆菌治疗组血浆内毒素阳性率降低,TNF-α以及IL-6明显降低,occludin表达升高。结论双歧杆菌对幼鼠急性肝缺血再灌注损伤有保护作用,该作用与双歧杆菌能维持肠黏膜屏障功能,减轻炎症反应以及减少内毒素移位有关。

Objective To study the protective effects of Bifidobacterium on hepatic ischemia-reperfusion and to study underlining the mechanisms. Methods Nighty SD rats were randomly divided into 3 groups： control group, model group and the Bifidobacterium group. A model of liver ischemia-reperfusion injury was established by blocking Hepatic artery and portal vein 45 rain and then reperfusion after 12h. Serum levels of alanine amino transferase （ALT） and aspartate amino transferase （AST） were detected by Henry volecity method. Histopathological features were observed by hematoxylin-eosin （HE）. The plasma endotoxin was measured by limulus ameobocyte lysate（LAL）. The expression of occluding was detected by histochemistry. Result The ALT and AST levels were significantly lower in the Bifidobacterium group than that of the model group. Meanwhile, the biopsy revealed reduced necrosis of liver cell. Compared with model group, the levels of serum endotoxin, TNF-α and IL-6 decreased and the expression of occludin was increased in rats in the Bifidobacterium group. Conclusion The hepato-protective effects of Bifidobacterium against acute hepatic ischemia-reperfusion injury in rat are associated with maintaining intestinal mucosal barrier function and reducing inflammation and endotoxin.