独一味颗粒对实验性肝纤维化大鼠TGF-β1/Smads信号通路的影响

Effect of Du Yi Wei granule on signaling pathways of TGF-β1/Smads in experimental liver fibrosis in rats

目的：探讨独一味颗粒对实验性肝纤维化大鼠TGF-β1／Smads信号通路的影响。方法：78只SD大鼠随机分为正常对照组、模型组、秋水仙碱组、独一味高、中、低剂量组共6组，每组13只。用CCl4诱导大鼠肝实质损伤性纤维化模型，模型组及各给药组皮下注射40％CCL4油剂（首剂5ml／kg，其后3ml／kg），正常对照组注射等量橄榄油，每3d1次，连续8周，同时模型组及各给药组进食高脂饲料，正常对照组进食普通饲料。独一味治疗组自实验开始分别给予高（2．4g／kg）、中（1．2g／kg）、低剂量（0．6g／kg）独一味颗粒灌胃，模型组和对照组灌等量生理盐水。用药至第8周CCl4造模结束。实验结束后，全部大鼠股动脉放血处死，离心分离血清，放射免疫法测定血清中透明质酸（Hyaluronic acid，HA）、血清层黏连蛋白（Laminin，LN）、III型前胶原（procollagen type III，PCIII）及IV型胶原（IV—C）的含量。迅速切取大鼠肝脏标本，光学显微镜下观察肝脏组织形态和纤维增生等情况，免疫组化测定肝组织中TGF-β1、Smad3蛋白表达。结果：独一味治疗组肝小叶结构存在，排列欠整齐，可见少量炎细胞浸润，程度较模型组减轻，纤维增生不明显。与模型组比较，独一味治疗组模型大鼠血清中HA、LN、PCⅢ、Ⅳ-C含量明显降低（P〈0．01—0．05），肝组织中TGF-β1、Smad3蛋白表达显著下降（P〈0．01）。结论：独一味具有较好的抗纤维化作用，其机制可能抑制TGF-β1的表达，干扰TGF-β1／Smad信号通路对靶基因的激活，下调Smad3表达而抑制ECM的合成和沉积，进而发挥抗纤维化作用。

Objective： To study the effects of ＂Duyiwei Granule＂ on TGF--β1/Smads signal transduction in hepatic tissues of the rats with liver fibrosis, Methods： Seventy-eight SD rats were randomized into six groups, including normal control group, model group, Colchicine group, ＂Duyiwei Granule＂ high-dose group （ 2.4 g/kg） , middle-dose group （ 1.2 g/kg）, low-dose group（0. 6 g/kg）. The rats in model group and treatment groups were subcutaneously injected with 40% CCl4 oil chloramphenicol plus high lipid forage to establish hepatic fibrosis model, while the normal control group were with olive oil and standard forage. Meanwhile, treatment was conducted in latter five groups for eight weeks. Hepatic biopsy was performed by optical microscope. Hyaluronic acid（ HA）, Laminin（LN） , procollagen type III（PCIII） and collagen type IV（IV-C） were detected by radioimmunoassay（RIA） and expressions of TGF -β1 and Smad3 protein in the hepatic tissues were detected by immunohistochemical assay. Results： Compared to normal control group, hepatic fibrosis model mice were treated ＂Duyiwei Granule＂ with lighter degree injury and unobvious fibrous hyperplasia. ＂Duyiwei Granule＂ groups were significantly lower than the model group on the level of HA, LN,PCIII and IV-C in serum （ P 〈 0. 01 ） and the expression of TGF-β1 and Smads3 in hepatic tissues （P 〈 0. 01 ）. Conclusions： ＂Duyiwei Granule＂ has significant inhibitory effects on CCl4 - induced hepatic fibrosis in rats, and its mechanism may be associated with the inhibition of TGF-β1 expression, the interference of TGF-β1/Smads signal transduction and the decrease of Smads3 expression.