A Study On The Effect And Mechanism Of Curcumin On Airway Mucus Secretion In Asthmatic Rats

Objective: To explore the effects of Curcumin on the airway goblet cells metaplasia and mucus secretion in asthmatic rats.Methods: Twenty-four female SD rats were randomly divided into 4 groups:negative control group,asthma model group,dexamethasone group and curcumin group(each n=6).For asthma model establishing,the rats were sensitized and challenged with ovalbumin,while the negative controls received saline.The lung tissue sections were stained with HE for histopathological examination,the number of airway epithelium goblet cells were examined with PAS,the concentration of MUC5 AC and IL-13 in BALF was measured by ELISA,and the expression of MUC5 AC in airway epithelial cells were demonstrated by immunohistochemistry.Western blot was used to detect the expression of EGFR and Foxa2 protein in the lung tissue of rats.Results: Compared with the negative control group,the airway mucosa of the asthma model group was thickened,and a large number of inflammatory cells were infiltrated in the trachea and blood vessels,and the number of airway epithelium goblet cells was significantly increased.Compared with asthma model group,the changes of airway inflammation in curcumin group and dexamethasone group were significantly reduced,and the number of goblet cells was significantly decreased.The proportion of eosinophils and lymphocytes in alveolar lavage fluid of asthmatic model group was significantly higher than that of negative control group,curcumin group and dexamethasone group(P<0.05).ELISA date showed that the levels of MUC5 AC and IL-13 in bronchoalveolar lavage fluid of asthma model group were significantly higher than those of negative control group,curcumin group and dexamethasone group(P<0.05).The expression of MUC5 AC in asthma model group was significantly higher than that in negative control group by immunohistochemistry(P<0.05),and the expression of MUC5 AC in curcumin group and dexamethasone group was weaker than that in asthma model group(P<0.05).Western blot showed that the expression of EGFR was significantly increased in asthmatic group and the expression of FoxA2 was significantly decreased(P<0.05).Compared with asthmatic group,the expression of EGFR in curcumin group was significantly decreased and the expression of FoxA2 was increased(P<0.05).The expression of EGFR in the lung tissue of dexamethasone group was significantly decreased(P<0.05),but the expression of FoxA2 was not significantly different from that of asthma model group(P> 0.05).Conclusion: Curcumin can inhibit the metaplasia of airway epithelial goblet cells and decrease the expression of MUC5 AC in airway epithelium of asthmatic rats.The mechanism of inhibition of mucus hypersecretion may be achieved by up-regulating the expression of FoxA2 and down-regulating the expression of IL-13 and EGFR in airway epithelium.