奥贝胆酸对DEHP亚急性暴露导致小鼠胆汁淤积的保护作用

Protective effect of obeticholic acid on cholestasis induced by subacute exposure to DEHP in mice

目的探讨奥贝胆酸(OCA)对邻苯二甲酸二(2-乙基己基)酯(DEHP)暴露致小鼠胆汁淤积的保护作用。方法动物实验一:将雌性ICR小鼠随机分为3组:对照组、DEHP低剂量组[50 mg/(kg·d)]、DEHP高剂量组[200 mg/(kg·d)],共灌胃18 d,建立胆汁淤积模型。动物实验二:将雌性ICR小鼠随机分为4组:对照组、OCA组、DEHP模型组[200 mg/(kg·d)]、DEHP+OCA组,共灌胃18 d,其中OCA灌胃时间为第12~18天。收集所有小鼠血液与肝脏组织,检测血清丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、总胆汁酸(TBA)水平和肝脏中的TBA水平;检测肝脏中法尼醇X受体(FXR)的蛋白表达水平以及FXR和其靶基因SHP的mRNA水平,HE染色观察肝脏组织病理变化。结果实验一:与对照组相比,仅DEHP高剂量组暴露后小鼠肝脏质量、肝重指数、血清和肝脏中TBA水平升高(P<0.01),表明高剂量DEHP暴露可导致小鼠胆汁淤积。实验二:与DEHP模型组相比,OCA处理后其肝脏质量、肝重指数、血清和肝脏中的TBA水平均降低(P<0.01)。与对照组相比,DEHP[200 mg/(kg·d)]处理后FXR的蛋白表达水平和其mRNA水平均降低;与DEHP模型组相比,OCA处理后FXR的蛋白表达水平以及FXR、SHP的mRNA水平均增加(P<0.05)。结论DEHP暴露可诱导小鼠胆汁淤积性肝损伤的发生,且OCA后处理对DEHP诱导的小鼠胆汁淤积有保护作用。

Objective To investigate the protective effect of obeticholic acid(OCA)on di(2-ethylhexyl)phthalate(DEHP)-induced cholestasis in mice.Methods Animal experiment 1:Female ICRmice were randomly divided into 3 groups:the control group,DEHP low-dose group[50 mg/(kg·d)]and DEHP high-dose group[200 mg/(kg·d)].All mice were administered with DEHP by gavage foR18 days.Animal experiment 2:Female ICRmice were randomly divided into 4 groups:the control group,OCA group,DEHP model group[200 mg/(kg·d)]and DEHP+OCA group.All mice were administered with DEHP by gavage foR18 days and the duration of OCA was 12-18 days.Serum and liveRtissues of mice were collected.Serum alanine aminotransferase(ALT),aspartate aminotransferase(AST),total bile acid(TBA)levels,liveRTBA levels,protein expression of farnesoid X receptoR(FXR)and mRNA levels of FXRand SHP were detected.HE staining was used to observe the pathological changes in liveRtissues.Results Experiment 1:Compared with the control group,the liveRweight,liveRcoefficient and the TBA concentrations in serum and liveRsignificantly increased only in DEHP[200 mg/(kg·d)]group(P<0.01),indicating that the modeling was successful.Animal experiment 2:Compared with the DEHP model group,the liveRweight and liveRcoefficient significantly decreased afteROCA treatment,and the TBA concentrations in serum and liveRboth decreased(P<0.01).Compared with the control group,the protein expression level and its mRNA level of FXRdecreased afteRDEHP[200 mg/(kg·d)]treatment;Compared with the DEHP model group,the protein expression of FXRand the mRNA levels of FXRand SHP significantly increased afteROCA treatment(P<0.05).Conclusion DEHP exposure can induce cholestatic liveRinjury in mice,and OCA posttreatment has a protective effect on DEHP-induced cholestasis in mice.