消癖丸干预二甲基亚硝胺诱导大鼠肝纤维化的效应及其机制

Effects of Chinese herbal medicine Xiaopi Pill in preventing rats from dimethylnitrosamine-induced liver fibrosis

目的:探讨消癖丸干预二甲基亚硝胺(dimethylnitrosamine,DMN)诱导的大鼠肝纤维化的作用。方法:采用0.5%的DMN溶液2mL/kg体质量腹腔注射,每周连续注射3d,每日1次,共4周,制备大鼠肝纤维化模型。第3周开始模型大鼠随机分为模型对照组和消癖丸组,消癖丸组给予消癖丸煎剂灌胃,模型对照组给予等量的生理盐水。治疗2周后,观察大鼠肝功能、肝组织病理学改变及肝纤维化相关指标α平滑肌肌动蛋白(alpha-smooth muscle actin,α-SMA)、转化生长因子β1(transforming growth factor-β1,TGF-β1)、组织金属蛋白酶抑制剂1(tissue inhibitor of metalloproteinase-1,TIMP-1)和血红素氧合酶1(heme oxygenase-1,HO-1)表达的变化。结果:(1)与正常大鼠比较,造模2和4周时模型大鼠血清丙氨酸氨基转移酶(alanine aminotransferase,ALT)、天冬氨酸氨基转移酶(aspartate aminotransferase,AST)、碱性磷酸酶(alkaline phosphatase,ALP)活性逐渐升高(P<0.01或P<0.05),4周时血清总胆红素(total bilirubin,TBil)含量显著增加(P<0.05);与4周模型组比较,消癖丸组血清ALT、AST、ALP、TBil水平均显著降低(P<0.01或P<0.05)。(2)模型大鼠肝组织炎症反应及胶原沉积逐渐加重,4周时部分大鼠肝组织已形成完整包绕的假小叶结构,肝组织羟脯氨酸(hydroxyproline,Hyp)含量显著增加(P<0.01);与4周模型组比较,消癖丸组肝组织炎症、胶原沉积明显减轻,肝组织Hyp含量显著降低(P<0.05)。(3)模型大鼠肝组织α-SMA蛋白表达逐渐增加,4周时显著高于2周模型组(P<0.01);聚合酶链式反应分析显示,肝组织α-SMA、TGF-β1、TIMP-1和HO-1mRNA的表达随着模型的进展逐渐升高(P<0.01);与4周模型组比较,消癖丸组肝组织α-SMA蛋白的表达及α-SMA、TGF-β1、TIMP-1、HO-1mRNA的表达均显著降低(P<0.01或P<0.05)。结论:消癖丸能够显著抑制DMN诱导大鼠肝纤维化的进展,且这一作用机制可能与抑制肝星状细胞活化有关。

OBJECTIVE： To explore the intervention effects of Xiaopi Pill （XPW）, a compound traditional Chinese herbal medicine, on the development progress of dimethylnitrosamine （DMN）-induced liver fibrosis in rats. METHODS： Liver fibrosis model was established by intraperitoneal injection of 0.5% DMN 2 mL/kg thrice a week for 4 weeks. Rats were divided into control group given saline and treatment group given XPW during the 3rd week of DMN injections. Rats were sacrificed at the end of the experiment, and then liver histological changes, liver function and mRNA expression of the liver fibrosis-associated markers were observed. RESULTS： （1） At the end of the 2nd and 4th weeks of DMN injection, serum levels of alanine aminotransferase （ALT）, aspartate aminotransferase （AST） and alkaline phosphatase （ALP） increased significantly in rats （P〈0.01 or P〈0.05）; content of total bilirubin （TBil） increased significantly compared with the normal group until the end of the 4th week （P〈0. 05）; compared with the model group after 4 weeks of DMN injection, the serum levels of ALT, AST, ALP and TBil were decreased remarkably in the XPW-treated group （ P〈0.01 or P〈0.05）. （2） The hepatic inflammation and collagen deposition in hepatic tissues increased by different degrees in experimental rats. Parts of pathological changes in the rat liver were found at the end of the 4th week, including a complete round structure of false flocculus round, meantime, the hydroxyproline content of hepatic tissue was increased significantly at the end of the 2nd and 4th weeks （P〈0.05）. Compared with the 4-week model group, the hepatic inflammation, collagen deposition and hydroxyproline content in hepatic tissues were alleviated dramatically （P〈0.05）. （3） Compared with the normal and 2nd week groups, protein expression of alpha-smooth muscle actin （α-SMA） was gradually increased, and that of the 4th week group were aggrandized significantly （P〈0.01）. Compared with the normal group, the mRNA expression of α- SMA, transforming growth factor-β1 （TGF-β1）, tissue inhibitor of melalloproteinase-1 （TIMP-1）, and heme oxygenase-1 （HO-1） was gradually increased. Further changes in above-mentioned abnormalities were found in the model rats at the end of the 4th week （P〈0.01）; while compared to the 4th week group, protein and mRNA levels of α-SMA and mRNA levels of TGF-β1, TIMP-1, and HO-1 were decreased significantly in the XPW group （P〈0.01 or P〈0.05）. CONCLUSION： Progressive DMN-induced liver fibrosis in rats can be suppressed by XPW〈 the mechanism may be associated with inhibition of the activated hepatic stellate cells.