Regulatory Effect of Shenge Yifei Capsule on TGF-β1/Smad Signaling Pathway in Rats with Chronic Obstructive Pulmonary Disease

[Objectives]This study aimed to study the effects of Shenge Yifei capsule on the TGF-β1/Smad signaling pathway in rats with chronic obstructive pulmonary disease(COPD).[Methods]Ten rats were randomly selected as the control group,and the other 40 rats were selected for modeling by fumigation combined with Klebsiella pneumoniae infection.A total of 38 rats were successfully modeled.They were randomly divided into model group(8 rats),low-dose Shenge Yifei capsule group(10 rats),high-dose Shenge Yifei capsule group(10 rats)and theophylline group(10 rats)in accordance with the principle of half male and half female.The rats in the model and control groups were given with distilled water by gavage,and the rats in the drug administration groups were given with corresponding drugs.The TGF-β1 level in the serum,and the expression levels of TGF-β1,Smad2,Smad3 and Smad7 and TGF-β1,Smad3 and Smad7 in airway tissues were detected.[Results]After 12 weeks,the serum TGF-β1 levels of the theophylline group and high-dose Shenge Yifei capsule group were lower than that of the low-dose Shenge Yifei capsule group(P<0.05).The expression levels of TGF-β1 and Smad3 in the theophylline group and high-dose Shenge Yifei capsule group were lower than that in the low-dose Shenge Yifei capsule group(P<0.05).The expression levels of TGF-β1 and Smad3 in the high-dose Shenge Yifei capsule group were lower than those in the low-dose Shenge Yifei capsule group and theophylline group(P<0.05).The expression levels of Smad7 and the proteins in the model group were lower than those in the other groups(P<0.05).The expression levels of Smad7 in the theophylline group and high-dose Shenge Yifei capsule group were higher than that in the low-dose Shenge Yifei capsule group(P<0.05).After 18 weeks,no significant difference was found in serum TGF-β1 level among the theophylline group and low and high-dose Shenge Yifei capsule groups(P>0.05).The expression levels of Smad7 and the proteins in the model group were lower than those in the other groups.The expression level of Smad7 in the high-dose Shenge Yifei capsule group was lower than that in the theophylline group(P<0.05).[Conclusions]Shenge Yifei capsule can regulate the TGF-β1/Smads signaling pathway.They can down-regulate the expression of TGF-β1,Smad2 and Smad3 and up-regulate the expression of Smad7,reducing the degree of airway modeling,delaying the development of COPD disease.Conventional high-dose Shenge Yifei capsule is more effective in inhibiting the expression of Smad2.