虎杖对肺纤维化大鼠肺组织中TGF-β_1表达的影响

Effect of Rhizoma Polygoni Cuspidati on expression of TGF-β_1 in rats with pulmonary fibrosis

目的:观察博莱霉素致肺纤维化大鼠中转化生长因子(TGF-β1)的表达及虎杖对其影响。方法:SD大鼠120只,随机分成正常对照组、模型组、虎杖预防组各30只,7d治疗组20只和28d治疗组10只。除正常对照组给予生理盐水外,其余各组均予气管内注射博来霉素诱导肺纤维化。虎杖预防组、7d治疗组和28d治疗组胃饲受试药物4g.kg-1.d-1,其余两组则予生理盐水灌胃。用RT-PCR和免疫组化观察各组大鼠肺组织TGF-β1mRNA和TGF-β1蛋白的表达。结果:与模型组比较,虎杖预防组和7d治疗组羟脯氨酸含量下降明显(P<0.05或P<0.01),TGF-β1mRNA和TGF-β1蛋白表达较模型组减弱(P<0.05或P<0.01)。结论:虎杖抑制肺组织中TGF-β1的表达,可能是虎杖抑制肺纤维化的作用机制之一。

Objective： To study the effects of Rhizoma Polygoni Cuspidati on expression of transforming growth factor beta 1 （TGF-β1） in rats with pulmonary fibrosis induced by bleomycin. Method： 120 male SD rats were randomly divided into five groups： the control group （ n = 30）, the bleomycin （BLM） model group （ n = 30）, the Rhizoma Polygoni Cuspidati prophylactic group （ n = 30）, the 7 th day treatment group （ n = 20） and the 28 th day treatment group （ n = 10）. The rat models of pulmonary fibrosis were established by intratracheal injection of bleomycin, while the control group was given with normal saline instead. The Rhizoma Polygoni Cuspidati prophylactic group received intragastric administration with 4ml·kg^-1· d^-1 Rhizoma Polygoni Cuspidati 2 days before setting up models. The 7 th day treatment group and the 28 th day treatment group received the treatment on the seventh day and the twenty-eighth days after establishing models respectively. The other two groups received saline instead. On the 3rd, 7th, 14th, 28th, 42th and 56th day after instillation of bleomycin,lung samples were obtained and the content of hydroxyproline in lung tissue homogenate was detected to judge the degree of fibrosis and the therapeutic efficacy. At the same time the express of TGF-β1 mRNA and TGF-β1 protein was examined by RT-PCR and immunohistochemical method. Results： Compared with the model group, the content of hydroxyproline in the Rhizoma Polygoni Cuspidati prophylactic group and the 7th day treatment group decreased significantly（ P 〈 0.05 or P 〈 0.01 ）, the express of TGF-β1 mRNA and TGF-β1 protein were significantly lower（ P 〈 0.05 or P 〈 0.01 ）. Conclusion： Rhizoma Polygoni Cuspidati downregulated the expression of TGF-β1 in lung tissue, which may be one of the mechanisms for retarding the progression of pulmanary fibrosis by Rhizoma Polygoni Cuspidati.