二甲双胍在对乙酰氨基酚诱导小鼠急性肝损伤中的保护作用

Protective role of metformin against acetaminophen-induced acute liver injury in mice

目的探讨二甲双胍(metformin,MET)在对乙酰氨基酚(acetaminophen,APAP)诱导小鼠急性肝损伤动物模型中的抗损伤及抗炎作用。方法采用小鼠腹腔注射APAP法诱导急性药物性肝损伤。30只小鼠按随机数字表法分为空白对照组、药物性肝损伤组(APAP组,腹腔内注射350 mg/kg APAP溶液)及二甲双胍处理组(APAP+MET组,于APAP暴露前30 min腹腔注射MET 400 mg/kg)。处死小鼠后取小鼠的血液标本,检测各组小鼠血清中谷草转氨酶(AST)和谷丙转氨酶(ALT)的变化,ELISA法检测血清肿瘤坏死因子-α(TNF-α)及白介素-6(IL-6)的水平,取肝脏组织检测其功能及病理变化,Western blot法检测肝组织中p-JNK、JNK的表达变化。结果与对照组相比,APAP组病理学显示大量的炎性细胞浸润,肝组织结构明显被破坏;血清AST、ALT、TNF-α和IL-6水平明显升高(P<0.05);p-JNK蛋白表达升高(P<0.05)。与APAP组相比,APAP+MET组小鼠血清病理损伤明显减轻;血清AST、ALT、TNF-α和IL-6水平下降(P<0.05);p-JNK蛋白表达水平降低(P<0.05)。结论MET预处理能够显著抑制APAP诱导小鼠急性肝损伤炎症因子的释放并对肝脏功能具有保护作用,这种保护作用可能与减少JNK磷酸化有关。

Objective To investigate the protective effect of metformin(MET)pretreatment against acetaminophen(APAP)-induced acute liver injury in mice and its potential mechanism.Methods Thirty male C57BL/6 mice(6-8 weeks old)were randomly divided into blank control group,liver injury model group(APAP group),and APAP+MET group.The mice in APAP group were intraperitoneally injected with 350 mg/kg APAP,while the mice in APAP+MET group were intraperitoneally injected with 400 mg/(kg·d)MET before the treatment of APAP.Blood samples were collected at 24 h after APAP modeling to determine the serum levels of aspartate transaminase(AST),alanine transaminase(ALT),tumor necrosis factor-α(TNF-α)and interleukin-6(IL-6).The liver tissues were collected to assess organ function and pathological changes.The expression of p-JNK and JNK in liver tissue was detected by Western blot.Results Compared with control group,the destruction of liver structure and the infiltration of inflammatory cells were more obvious in APAP group.Compared with control group,the serum levels of ALT,AST,TNF-α,IL-6 were increased in APAP group(P<0.05),and the expression of p-JNK protein in liver tissue was also increased(P<0.05).Compared with APAP group,the serum levels of ALT,AST,TNF-α,IL-6 were decreased in APAP+MET group(P<0.05),the histopathological abnormalities were attenuated,and the expression of p-ERK protein in liver tissue was significantly decreased(P<0.05).Conclusion MET can protect against APAP-induced acute liver injury,which may be related to the down-regulation of p-JNK expression.