The Effect Of TGF-β₁/Smad Signaling Pathways In Airway Mucus Hypersecretion Of Asthmatic Mice

Part 1 The airway mucus hypersecretion in asthmatic miceObjective To investigate airway inflammation in asthmatic mice, and confirm that asthmatic mice have mucus hypersecretion. Method Twenty clean BALB/c rats were randomly divided into two groups:control group asthmatic model group(OVA group, n=10), (NS group, n=10). asthmatic model group made asthmatic model in sensitized and challenged with ovalbumin (OVA), control group was sensitized and challenged with normal sodium. After three weeks, total cells and differential inflammatory cells were counted in bronchoalveolar lavage fluid (BALF), the levels IL-4 and TNF-a in BALF were determined by enzyme-linked immuno sorbent assay (ELISA), positive staining in the area of the goblet cell in airway wall was observed by a first blue-periodic acid Schiff reagent staining (AB-PAS), the expression of Muc5ac in airway were observed by immunohistochemical staining, the expressions of Muc5ac mRNA in airway tissue were observed real-time quantitative reverse transcription polymerase reaction (RT-PCR). Result Total cells, lymphocyte and eosinophil cells in BALF of athmatic model group were obviously higher than control group(P<0.01); the levels of IL-4 and TNF-a in BALF, positive staining in the area of the goblet cell in airway wall, and Muc5ac in the protein and gene level were higher than those in control group(P<0.01). Conclusion asthmatic mice have apparente inflammatory cell infiltration, and secrete a great quantity mucosubstance.Pary 2 The effect of TGF-β1/Smad signaling pathways in airwaymucus hypersecretion of asthmatic mice treated with pirfenidone Objective To investigate the effect of TGF-β1/Smad signaling pathways on mucus of hypersecretion asthmatic mice treated with pirfenidone.Methods Forty clean BALB/c rats were randomly divided into five groups:control group (NS group, n=8), asthmatic model group(OVA group, n=8), dexamethasone (DEX) treatment group(OVA+DEX group, n=8)),pirfenidone (PFD) treatment group (OVA+PFD group, n=8), Solvent control group (OVA+SJ group,n=8).Total cells and differential inflammatory cells were counted in bronchoalveolar lavage fluid (BALF), the levels of IL-4 and TNF-a in BALF were determined by enzyme-linked immuno sorbent assay (ELISA), positive staining in the area of the goblet cell in airway wall was observed by alcian blue/periodic acid schiff staining (AB-PAS), the expressions of Muc5ac in airway tissue and TGF-β1 in lung tissue were observed by immuneohistochemical staining, the expressions of Muc5acmRNA and TGF-β1mRNA and Smad3 mRNA and Smad4 mRNA in lung tissue were observed by real-time quantitative reverse transcription polymerase reaction (RT-PCR).Result Total cells,eosinophil cells and lymphocyte cells in BALF, the levels of IL-4 and TNF-a in BALF, positive staining in the area of the goblet cell in airway wall, and the expression of Muc5ac in the protein and gene level of OVA group were obviously higher than those in control group and (OVA+PFD) group (P<0.01), TGF-β1, Smad3 and Smad4 in the protein and gene level were higher than those in control group and (OVA+PFD) group (P<0.01), while were Non-significance difference Between OVA group and (OVA+DEX) control group(P>0.05).Conclusion The expressions of TGF-β1,Smad3 and Smad4 in the protein and gene level in lung tissue were higher than those in control group,and Muc5ac in the protein and gene level in airway tissue were higher than those in control group(P<0.01) PFD may inhibit the expressions of TGF-β1,Smad3 and Smad4 in the protein and gene level in lung tissue, and down the expressions of Muc5ac in the protein and gene level in airway tissue, illustrating TGF-β1/Smad signal pathway play a role in airway mucus hypersecretion.