Regulatory Effect Of Self-made Traditional Chinese Medicine And Pirfenidone On TGF-?1/Smad Signaling Pathway In Rat Early Stage Of Silicosis

?Objective?The aim of this study was to investigate the interventional effect of self-made Traditional Chinese Medicine and pirfenidone on the early stage of pulmonary fibrosis in rats exposed to silica dust,and to explore its possible mechanism from TGF-?1/Smad pathway,which provide a theoretical basis for clinical treatment.?Methods?1.SD rats were randomly divided into control group,model group,pirfenidone group?50mg/kg,100mg/kg?,with 16 rats included in each group.Rats in the control group were intratracheally instilled with 1.0 ml normal saline,and the rest of the rats were perfused with 1.0 ml SiO₂ suspension.Gavage were given from the next day after model establishment.The rats in pirfenidone group were treated with the 50 mg/kg and 100 mg/kg pirfenidone,respectively,while the rats in control and model group were perfused with 1%carboxymethyl cellulose.Rats were killed on the 14th and 28th days after treatment to perform HE and Masson staining,and to determine the levels of TGF-?1,TNF-?,IL-1?and IL-6 in the lung tissues of rats,and to detect the protein expression level of Col-?40?,TGF-?1,Smad2/3,E-cad and Vimentin in lung tissues.2.SD rats were randomly divided into control group,model group,traditional chinese medicine?TCM?particles group?500mg/kg,1000mg/kg?,with 16 rats included in each group.Rats in the control group were intratracheally instilled with 1.0 ml normal saline,and the rest of the rats were perfused with 1.0 ml SiO₂ suspension.Gavage were given from the next day after model establishment.The rats in TCM particles group were treated with the 500 mg/kg and 1000 mg/kg TCM particles,respectively,while the rats in control and model group were administered with 0.9%normal saline.Rats were killed on the 14th and 28th days after treatment to perform HE and Masson staining,and to determine the levels of TGF-?1,TNF-?,IL-1?and Col-?40?in the lung tissues of rats,and to detect the protein expression level of Col-?40?,TGF-?1,Smad2/3 and p-Smad2/3 in lung tissues.3.SD rats were randomly divided into control group,model group,anti-lung fibrosis traditional chinese medicine particles group?500mg/kg,1000mg/kg?,with 16 rats included in each group.Rats in the control group were intratracheally instilled with 1.0 ml normal saline,and the rest of the rats were perfused with 1.0 ml SiO₂ suspension.Gavage were given from the next day after model establishment.The rats in chinese medicine group were treated with the 500 mg/kg and 1000 mg/kg chinese medicine particles,respectively,while the rats in control and model group were administered with 0.9%normal saline.Rats were killed on the14th and 28th days after treatment to perform HE and Masson staining,and to determine the levels of TGF-?1,TNF-?and IL-1?in the lung tissues of rats,and to detect the protein expression level of TGF-?1,Smad2/3,E-cad and Vimentin in lung tissues.?Results?1.The interventional effect of pirfenidone on pulmonary fibrosis in rats exposed to silica dustPirfenidone can inhibit weight loss of silica-induced rats,relieve the infiltration of inflammatory cells,the damage of alveolar structure and reduce the silicosis fibrosis.The levels of TGF-?1,TNF-?,IL-1?and IL-6 in the lungs of the model group rats treated for 14days and 28 days were higher than those of the control group?P<0.05?.The levels of those in the low dose group and high dose group were lower than the model group?P<0.05?.And the level of each index in the 100 mg/kg pirfenidone group was lower,the difference was statistically significant?P<0.05?.In addition,after pirfenidone intervention for 14 days and28 days,the protein expression of vimentin was down-regulated and the protein expression of E-cadherin was up-regulated in lung tissues,and pirfenidone reduced the expression of TGF-?1 and smad2/3 in the lungs induced by SiO₂.2.The interventional effect of TCM particles on pulmonary fibrosis in rats exposed to silica dustThe intervention of TCM particles could effectively inhibit the pathological changes of lung tissues induced by SiO₂.On the 14th day and the 28th day after model establishment,the contents of TGF-?1,TNF-?,IL-1?and Col-?40?in the rats lung tissues of the model group were higher than those in the control group,while the level of index was decreased after the intervention of traditional Chinese medicine,and the contents of the 1000 mg/kg group was lower,and the difference was statistically significant?P<0.05?.On the 14th day and the 28th day after model establishment,the expression levels of Col-?,TGF-?1,Smad2/3 and p-Smad2/3 protein in the lung tissues of the model group were higher than those in the control group,while the expression level of Col-?40?,TGF-?1,Smad2/3 and p-Smad2/3 protein was decreased after the intervention of traditional Chinese medicine,the level of the 1000 mg/kg group was lower,and the difference was statistically significant?P<0.05?.3.The interventional effect of anti-lung fibrosis Traditional Chinese Medicine particles on pulmonary fibrosis in rats exposed to silica dustAfter 14 and 28 days of SiO₂ stimulation,Rats in model group had obvious inflammatory reaction and accumulation of collagen fibers.The intervention of Traditional Chinese Medicine could effectively inhibit the pathological changes of lung tissues and reduce the contents of TGF-?1,TNF-?and IL-1?in the rats lung tissues.Traditional Chinese Medicine can increase the expression of E-cad and decrease the protein expression of Vimentin in lung tissues,thereby improving epithelial-mesenchymal transition of lung tissues.At the same time,the intervention of anti-lung fibrosis TCM particles inhibited the positive expression of TGF-?1 and Smad2/3 protein in lung tissues,and the expression of 1000 mg/kg group was lower,the difference was statistically significant?P<0.05?.?Conclusion?1.The intervention of pirfenidone can effectively alleviate SiO₂-induced the alveolar inflammation and the degree of silicosis in rats,and inhibit the EMT induced by silica in rats.It may be related to the regulation of the TGF-?1/Smad2/3 signaling pathway.However,its specific mechanism of action still needs further research.2.TCM particles can inhibit the pathological changes of rat lung tissues induced by SiO₂,can reduce the expression of pro-inflammatory and pro-fibrotic factors and the content of Col-I in lung tissues,thereby inhibiting the synthesis of extracellular matrix in rat lung tissue and playing an anti-fibrosis effect.The inhibition may be related to the regulation of TGF-?1/Smads pathway by Chinese medicine in rat lung tissues.3.Anti-lung fibrosis traditional chinese medicine particles can alleviate alveolar inflammation and silicosis fibrosis in rats exposed to silica,can inhibit SiO₂-induced the increase of Vimentin expression induced by SiO₂ and the decrease of E-cad expression,thereby inhibiting the epithelial-mesenchymal transition in rat lung tissue.The inhibition effect may be associated with decreased expression of TGF-?1/Smad in lung tissues.