Effects of sodium ferulate on lung mRNA expression of transforming growth factor-β_1 signal transduction molecule in pulmonary fibrosis rats

Objective To investigate the effects of sodium ferulate on lung expression of transforming growth factor-β1(TGF-β1) signal transduction molecule mRNA in rats of pulmonary fibrosis,and explore the intervention mechanism of sodium ferulate on pulmonary fibrosis.Methods A rat model of pulmonary fibrosis was induced by intratracheal injection of bleomycin(5 mg/kg).Thirty SD rats were randomly divided into three groups(n=10 in each group),ie.a control group,a pulmonary fibrosis model group,and a sodium ferulate group.The lung histopathology and the expression of collagen was examined by HE staining and collagen fiber staining respectively.The expressions of TGF-βRII and Smad4 mRNA in the lung tissue were detected by in situ hybridization.The expression of TGF-β1 mRNA was detected by real-time fluorescence-quantification RT-PCR.Results Collagen fiber staining indicated that the pulmonary collagen deposition in the model group was more significant than that in the control group and sodium ferulate group(P0.001).The mRNA expressions of pulmonary TGF-β1,TGF-βRII and Smad4 were significantly higher in the model group than those in the control group(all P0.01),and were significantly lower in the sodium ferulate group than those in the model group(all P0.05).Conclusions Sodium ferulate can effectively suppress pulmonary fibrosis through inhibition of the mRNA expression of TGF-β1,TGF-βRII and Smad4 in the lung tissue,thus modulate the TGF-β1/Smad4 signal transduction and inhibit the target gene activation.