肉苁蓉乙醇提取物抗大鼠免疫性肝纤维化的作用及其机制

摘要

目的：探讨肉苁蓉乙醇提取物肉苁蓉苯乙醇样糖苷（CPhG）对大鼠免疫性肝纤维化的作用及其作用机制。方法 SD大鼠75只，随机分为正常对照组、模型组、复方鳖甲软肝片（0.6 g·kg-1）阳性药对照组、CPhG 0.125，0.25和0.5 g·kg-1组，CPhG组每组13只，其他每组12只，皮下和尾静脉注射牛血清白蛋白诱导大鼠肝纤维化模型，造模同时ig给予相应药物，每日1次，共15周。测定大鼠肝指数，Masson染色法观察肝组织纤维化，全自动化分析仪测定血清谷丙转氨酶（GPT）、谷草转氨酶（GOT）、碱性磷酸酶（ALP）、总蛋白（TP）和白蛋白（ALB）含量变化，羟脯氨酸（HyP）测定试剂盒测定肝匀浆中HyP含量的变化；免疫组化法观察肝组织中Ⅰ型和Ⅲ型胶原蛋白表达的变化。结果与正常对照组比较，模型组大鼠肝指数显著升高（P<0.05）。模型组大鼠肝组织胶原纤维延伸连接，包绕整个肝小叶使正常肝小叶结构破坏，大方型假小叶形成；模型组大鼠血清中GPT，GOT，ALP，TP和ALB含量及肝匀浆中HyP含量显著升高（P<0.05，P<0.01），Ⅰ型和Ⅲ型胶原蛋白的表达均显著升高（P<0.01）。与模型组比较，CPhG 0.125，0.25和0.5 g·kg-1能降低肝纤维化大鼠肝指数（P<0.05），肝组织形态与正常对照组接近，血清中GPT，GOT，ALP，TP和ALB含量及肝匀浆中HyP含量降低（P<0.05，P<0.01），且能抑制肝组织中Ⅰ型和Ⅲ型胶原蛋白的表达（P<0.05，P<0.01）。结论 CPhG能降低免疫性大鼠肝纤维化程度，其机制可能与降低Ⅰ型和Ⅲ型胶原蛋白表达进而抑制肝星状细胞活化、减少胶原生成有关。%OBJECTIVE To study the anti-fibrotic effect of Cistanche phenylethanoid glycosides (CPhG) in bovine serum albumin (BSA)-induced liver fibrosis in rats and its possible mechanism METHODS Seventy-five SD rats were randomly divided into six groups:normal control(distilled water-treated),model(BSA-treated),positive drug〔BSA-treated+compound Biejiarangan tablets(BJRG) 0.6 g·kg-1〕,and BSA-treated+CPhG(0.125,0.25 and 0.5 g·kg-1)groups. There were thirteen rats in each BSA-treated+CPhG(0.125,0.25 and 0.5 g·kg-1)group and twelve rats in other groups. Subcutaneous injection and tail vein injection of BSA immunity were used to induce the rat liver fibrosis model. Meanwhile, different therapeutic drugs were ig adminstered to rats. After the experimental period,rats were fasted for 12 h prior to 10%chloral hydrate administration and immediately euthanized. The liver was weighed to calculate the liver index. Glutamic-pyruvic transaminase (GPT),glutamic-oxalactic transaminase (GOT),alkaline phosphatase(ALP),total protein(TP)and albumin(ALB)were evaluated by the Mind-Ray automatic biochemical analyzer. The density of hydroxyproline (HyP) in liver tissues was determined using a spectrophotometric method according to the kit′s instructions. Histopathological changes and expressions of typeⅠ and typeⅢcollagens in liver tissues were also determined by immunohisto⁃chemical staining. RESULTS Compared with the normal control group,collagen fibers of liver tissues in the model group extended their links and enveloped the entire lobule,causing lobular structural damage and the formation of pseudolobules. The liver index(P<0.05),GPT,GOT,ALP,TP and ALB serum levels(P<0.05),HyP content(P<0.01)were significantly increased,so was the expression of typeⅠcollagens and typeⅢcollagens(P<0.01)in the model group. Compared with model group,various doses (0.125,0.25 and 0.5 g · kg-1) of CPhG significantly reduced the BSA-induced elevation of the liver index;GPT,GOT,ALP,TP and ALB serum levels(P<0.05),and HyP content decreased(P<0.01);the morphology of the pathological tissue sections was close to that of the normal control group,and CPhG significantly reduced the expression of two types of collagens(P<0.01). CONCLUSION CPhG can significantly reduce the degree of BSA-induced liver fibrosis in rats. The mechanism may be associated with down-regulation of two types of collagens and suppression of the activation of hepatic stellate cells.