中脑星形胶质细胞神经营养因子在利福平诱导的小鼠胆汁淤积性肝损伤中的作用

Exploring effect of MANF in cholestatic liver injury in mice induced by rifampicin

目的探究中脑星形胶质细胞神经营养因子(mesencephalic astrocyte-derived neurotrophic factor,MANF)在利福平(rifampicin,RFP)诱导的胆汁淤积性肝损伤中的作用。方法借助肝细胞MANF特异性敲除(hepatocyte-specific MANF knockout,HKO)小鼠模型,观察MANF基因缺失对RFP诱导的小鼠胆汁酸转运体表达的影响。体外观察MANF敲减后对人肝癌细胞HepG2的核因子红细胞系2相关因子2(nuclear factor erythroid 2-related factor 2,Nrf2)的影响。结果与野生型(wild type,WT)小鼠相比,RFP处理的WT小鼠的胆盐输出泵(bile salt export pump,BSEP)以及多药耐药相关蛋白4(multidrug resistance-associated protein 4,MRP4)的蛋白和基因表达水平增加。然而,与RFP处理的WT小鼠相比,HKO小鼠中BSEP、多药耐药蛋白1(multidrug resistance protein 1,MDR1)、MRP2/3/4和有机溶质转运蛋白α(organic solute transporterα,OSTα)的蛋白和(或)基因表达水平明显降低。体外细胞MANF敲减会削弱RFP诱导的Nrf2的表达以及核内移。结论MANF可能通过调节Nrf2的表达调控BAT的适应性表达,在RFP诱导的肝损伤中发挥保护作用。

Aim To investigate the involvement of mesencephalic astrocyte-derived neurotrophic factor(MANF)in rifampicin(RFP)-induced cholestatic liver injury.Methods We investigated the impact of MANF gene deletion on rifampicin-induced BAT expression in mice by the MANF gene knockout mouse model.We investigated the influence of MANF knockdown on nuclear factor erythroid 2-related factor 2(Nrf2)in HepG2 cells by the MANF knockdown cell model.Results Compared with the wild-type(WT)mice,the mRNA and protein expression levels of bile salt export pump(BSEP)and multidrug-resistant associated protein4(MRP4)significantly increased in WT mice treated with RFP.However,compared to the WT mice treated with RFP,the mRNA and protein expression levels of BSEP,Multidrug resistance protein 1(MDR1),multidrug resistance associated proteins 2/3/4(MRP2/3/4),and organic solute transport proteinsα(OSTα)were significantly reduced.In cell experiments we found that MANF knockdown weakened the expression of Nrf2 and its nuclear translocation by RFP.Conclusion MANF may regulate adaptive BAT expression by modulating Nrf2 expression,thereby playing a protective role in RFP-induced liver injury.