Study On The Mechanism Of Bufei Decoction Regulating Airway Remodeling In COPD Based On TGF-β1/Smads Signaling Pathway

Objective: To study the intervention effect of Bufei on chronic obstructive pulmonary disease(COPD)rats,and to explore the possible mechanism of Bufei in regulating airway remodeling of COPD,so as to provide certain basis for the clinical application of Bufei in the treatment of COPD.Methods: A total of 32 SPF SD male rats were selected and divided into blank group,model group and traditional Chinese medicine group according to random number table,including 12 rats in model group and 10 rats in other groups.COPD model was replicated by fumigation and LPS method,and 2 rats were randomly selected from the model group for model determination.After successful modeling,the original formula of Bufei was administered intragastrically on the 29 th day,and relevant samples were collected after 15 days of continuous administration.The general state and behavior of rats were observed dynamically during the whole experiment.Lung tissues of rats were collected,and pathological changes of lung tissues were observed by HE staining and Masson staining.The expression of α-SMA(smooth muscle actin)in lung tissues was detected by IF and the contents of TGF-β1,Smad2,Smad3 and Smad7 in lung tissues were detected by Western-blot.Results:1.General behavior of rats: Bufei Decoction can improve the symptoms of COPD rats,such as:The rats in the model group showed irritability,strong excitability,strong aggression,waxy and dry hair,and liked to be in a quiet place.Pallor was also observed in the claws and armors.In the process of fumigation,increased respiratory rate was observed,accompanied by increased nasal secretions.2.Pathological changes of lung tissue airway remodeling in each group:(1)Compared with the blank group,the relative thickness of smooth muscle and airway wall in the model group was significantly increased,the difference was statistically significant(P < 0.05).There was no significant difference between the Bufei group and the blank group(P > 0.05).Compared with model group,Bufei could reduce the hyperplasia of bronchial duct wall and smooth muscle,and the difference was significant(P < 0.05).(2)Rat lung tissue is normal blank group,model group rats rats lumen narrowing obviously,lumen of discontinuity,airway mucosa epithelial shedding,at the same time also can see mucosal fold circuity,toward the endobronchial growth,cilia arranged disorder,inflammatory cells infiltration around,with inflammatory cells together ball performance,mucous plug formation,increase in the number of goblet cells on the wall,Smooth muscle thickens,alveolar cavities break down and fuse,and capillaries multiply.However,the pathological staining of the small airway and alveolar structure of the rats in the Bufei decoction group was improved compared with that in the model group.(3)Compared with the blank group,bronchial mean on the road the positive expression of collagen fibers increased significantly in the model group,the difference was statistically significant(P < 0.05),and compared with model group,fill small soup can reduce pulmonary bronchial collagen fiber content,the significant difference(P < 0.05).3.The expression changes of α-SMA,TGF-β1,Smad2/3 and Smad7 in rat lung tissue(1)Compared with the blank group,the expressions of α-SMA,TGF-β1,Smad2 and Smad3 in the lung tissue were increased(P < 0.05),while the expression of Smad7 in the lung tissue was decreased(P < 0.05),the difference was statistically significant.(2)Compared with model group,the expressions of α-SMA,TGF-β1,Smad2 and Smad3 in lung tissue of rats in Bufei group were decreased(P < 0.05),and the expression of Smad7 in lung tissue was increased(P < 0.05).Bufei can regulate TGF-β1/Smads to improve airway remodeling and reduce the proliferation of smooth muscle.Conclusion:1.Bufei interferes with airway remodeling by down-regulating the expression of TGF-β1,reducing the expression level of Smad2/3 and up-regulating the expression level of Smad7,suggesting that Bufei may interfere with airway remodeling of COPD by regulating TGF-β1 / Smads signaling pathway.2.Bufei can down-regulate the expression of α-SMA in the lung tissue of rats,suggesting that Bufei may improve the airway remodeling of COPD by improving the proliferation of airway smooth muscle cells.