鬼针草总黄酮对肝纤维化大鼠肝组织TGF-β_1/smad通路的影响

Effect of Total Flavonoids of Bidens bipinnata on TGF-β_1/smad Pathway of Liver Tissue in Rats with Liver Fibrosis

目的:研究鬼针草总黄酮(TFB)对肝纤维化大鼠肝组织中转化生长因子β1/smad(TGF-β1/smad)通路表达的影响。方法:四氯化碳(CCl4)复制肝纤维化大鼠模型,随机分为5组:模型组、阳性药秋水仙碱组(0.2 mg·kg-1)、TFB低、中、高剂量组(60,120,240 mg·kg-1),并设正常组,连续灌胃30 d。检测大鼠血清中丙氨酸转氨酶(ALT)、门冬氨酸转氨酶(AST)和总胆红素(TBil)的水平,以及测定肝组织中透明质酸(HA)、层粘连蛋白(LN)、III型前胶原(PCIII)和羟脯氨酸(Hyp)的含量。免疫组化检测肝组织中转化生长因子-β1(TGF-β1)阳性细胞的表达,Western blot法测定肝组织中smad2和smad3表达,Masson染色观察肝组织病理学变化。结果:与模型组比较,TFB可有效降低肝纤维化大鼠血清中AST,ALT,TBil水平(P<0.01),降低肝组织中HA,LN,PCIII和Hyp含量(P<0.01);TGF-β1阳性细胞数量明显减少(P<0.01),以及肝组织中smad2和smad3有效地下调(P<0.01),并减轻肝纤维化病变。结论:鬼针草总黄酮对肝纤维化大鼠具有防治作用,其机制可能与调节TGF-β1/smad通路而抑制胶原生成有关。

Objective： To study the effect of the total flavonoids of Bidens bipinnata （TFB） on the TGF- β1 smad pathway of liver tissue in rats with liver fibrosis. Method： Liver fibrosis in rats was established by CC14 , and then the rats were randomly divided into five groups： model group, colchicine group （0.2 mg·kg^-1X） , low-, medium-and high-dosage groups of TFB （60, 120, 240 mg ·kg^-1X）, as well as the normal group was set up. The drugs were given to rats daily for 30 consecutive days. The activities of alanine aminotransferase （ALT）, aspartate aminotransferase （AST） and total bilirubin （TBil） in serum were examined, and the levels of hyaluronic acid （HA）, laminin （LN）, precollagen III （PCIII） and hydroxyproline （Hyp） in hepatic tissue were examined. The transforming growth factor-β1 （TGF-β1） -immunoreactive cells were determined by immunohistochemical assay, and the expression of smad2 and smad3 in hepatic tissue was determined by Western blot. In addition, the hepatic pathological changes were observed by Masson staining. Result： Compared with model group, TFB effectively decreased the activities of AST, ALT and TBil in rats with liver fibrosis （P 〈 0.01 ） , the contents of HA, LN, PCIII and Hyp in homogenate were decreased （P 〈 0.01 ）. The quantity of TGF-β1-immunoreactive cells was reduced （P 〈 0.01 ）. The smad2 and smad3 protein level was down-regulated in hepatic tissue （P 〈 0.01 ）. Moreover, liver fibrosis was alleviated. Conclusion： TFB has protective effect on the CC14-induced liver fibrosis in rats, the mechanism may be implicated in regulating the TGF-β1/smad pathway to inhibit collagenation.