Effect of Danshao Huaxian capsule on the expression of TGF-β_1 and Smad_(3/7) in the lung in rats with fibrosis pulmonary

OBJECTIVE To investigate the effect of Danshao Huaxian capsule(DSH) on TGF-β_1 and Smad_3/7 expression in rats with pulmonary fibrosis.METHODS Thirty Spague-Dawley rats were randomly divided into the control group,model group and test group.The model group and the test group were induced pulmonary fibrosis with endotracheal injection of bleomycin(5 mg·kg~-1),while the control group was given normal saline instead.From the second day of injection,the rats in the test group were administered intragastricly with DSH(0.8 g·kg~-1·d~-1),while the other rats were given normal saline instead.All rats were sacrificed at the twenty-eighth day,and the pathological changes in rats were detected.The expression of TGF-β_1 and Smad_3/7 were examined by immunohistochemical staining.RESULTS In model group,the lung coefficient,the Hyp content,expressions of TGF-β_1 and Smad_3 were significantly increased,while the expression of Smad_7 was decreased.Compared with model group,the lung coefficient were significantly decreased,pulmonary alveoli inflammation and pulmonary fibrosis were relieved,the Hyp content and expression of TGF-β_1 and Smad_3 were obviously decreased in the test group,but Smad_7 was significantly increased.CONCLUSION DSH has a good effect against experimental pulmonary fibrosis in rats.The mechanism may be associated with the influence of DSH on TGF-β_1/Smads signal transduction with down-regulating the expressions of TGF-β_1 and Smad_3 while up-regulating the expression of Smad_7.