吗替麦考酚酯减轻四氯化碳诱导的小鼠肝纤维化

Effect of mycophenolate mofetil alleviates carbon tetrachloride-induced liver fibrosis in mice

目的:肝纤维化是由慢性肝病导致的严重病理后果,并最终发展为肝硬化。吗替麦考酚酯(mycophenolate mofetil,MMF)是器官移植术后常用的免疫抑制剂,与肝纤维化的关系尚不明确。本研究旨在探讨MMF对小鼠肝纤维化的影响及其机制。方法:选用雄性8周龄C57BL/6小鼠24只,将其随机分为空白对照组、MMF组、四氯化碳(carbon tetrachloride,CCl_(4))组、CCl_(4)+MMF组(每组均n=6)。小鼠处死后,取血清检测丙氨酸转氨酶(alanine aminotransferase,ALT)及天冬氨酸转氨酶(aspartate aminotransferase,AST);肝组织行Masson染色评估纤维化程度,采用免疫组织化学染色评估I型胶原蛋白(collagen I,COL1)表达水平;然后采用蛋白质印迹法检测转化生长因子-β1(transforming growth factor-β1,TGF-β1)和α-平滑肌肌动蛋白(alpha-smooth muscle actin,α-SMA)的蛋白质表达水平;最后利用real-time PCR检测TGF-β1、α-SMA及COL1的mRNA相对表达量。结果:与CCl_(4)组相比,CCl_(4)+MMF组小鼠的ALT与AST均下降(均P<0.05),肝纤维化程度明显减轻,肝组织中COL1的沉积明显减少(P<0.01)。与CCl_(4)组相比,CCl_(4)+MMF组小鼠肝组织中TGF-β1与α-SMA的蛋白质表达水平均明显降低(均P<0.05);TGF-β1、α-SMA及COL1的mRNA相对表达水平均明显降低(均P<0.05)。结论:MMF能减轻CCl_(4)诱导的小鼠肝纤维化程度,其机制可能与抑制TGF-β1的基因表达及蛋白质合成有关,本研究有望为肝纤维化的治疗提供新方向。

Objective:Hepatic fibrosis is a serious pathological consequence of chronic liver disease.Mycophenolate mofetil(MMF)is a commonly used immunosuppressant after organ transplant.However,the relationship between MMF and hepatic fibrosis remains unclear.This study aims to explore the effect of MMF on hepatic fibrosis in mice and the potential mechanism.Methods:A total of 24 mice(male,8-week old,C57BL/6)were randomly divided into a control group,a MMF group,a carbon tetrachloride(CCl_(4))group and a CCl_(4)+MMF group(n=6 in each group).After the mice were sacrificed,the serum alanine aminotransferase(ALT)and aspartate aminotransferase(AST)levels were detected.The liver tissues were taken up for Masson staining and collagen I(COL1)immunohistochemistry.The levels of transforming growth factor-β1(TGF-β1)andα-smooth muscle actin(α-SMA)were detected by Western blotting.Finally,the levels of mRNA for TGF-β1,α-SMA,and COL1 were detected using real-time PCR.Results:Compared with the CCl_(4) group,the ALT and AST levels were lower(both P<0.05),the degree of liver fibrosis was alleviated,and the deposition of COL1 in the liver was significantly decreased(P<0.01)in the CCl_(4)+MMF group.Compared with the CCl_(4) group,the protein expression levels of TGF-β1 andα-SMA were significantly decreased(both P<0.05)and the relative expression levels of TGF-β1,α-SMA and COL1 mRNA in the liver were significantly decreased(all P<0.05)in the CCl_(4)+MMF.Conclusion:MMF could reduce CCl_(4)-induced hepatic fibrosis,which might be related to the inhibition of TGF-β1.This study is expected to provide a target for the treatment of hepatic fibrosis.