Effect of epidermal growth factor receptor on airway mucin production in asthmatic mice and its mechanism

Abstract

Objective To explore the relationship between airway mucin production and expression of epidermal growth factor receptor(EGFR)and transforming growth factor alpha(TGF-α)in asthmatic mice and the effect of the epidermal growth factor receptor tyrosine kinase inhibitor(AG1478)in asthmatic mice.Methods Thirty-two male BALB/c mice were randomly divided into four groups:control group,asthma group,AG1478 treated group,dexamethasone treated group.Mice were sensitized and challenged with ovalbumin establish the asthmatic model.Periodic acid Schiff staining were used to observe the goblet cells and mucus of airway.Immunohistochemistry was used to detect the protein expression of TGF-α.RT-PCR was used to detect the mRNA expression of EGFR.Results After repeated allergen challenge,obvious infiltration of inflammatory cells and proliferation of goblet cells and mucus hypersecretion were demonstrated in asthmatic group.Expression levels of EGFR and TGF-α in the epithelial cells of bronchi were significantly higher in asthmatic animals than those in control animals.Compared with asthmatic group,there was mild inflammation reaction,decreased in proliferation of goblet cells and lower expression of EGFR and TGF-α in AG1478 treated group and dexamethasone treated group,and they were not significantly higher than those in control animal.(P<0.05).Condasions EGFG and TGF-α mucin involved in airway mucin production.AG1478 may be effective in reducing mucin production in asthmatic mice.The AG1478 ameliorates the progression of airway muein production following prolonged allergen challenge via regulation of EGFR signal cascades. Key words: Epidermal growth factor receptor; Transforming growth factor alpha; Asthma; Mucin; Epidermal growth factor receptor tyrosine kinase inhibitor(AG1478)