Oleanolic acid and ursolic acid derived from Cornus officinalis Sieb. et Zucc. suppress epidermal growth factor- and phorbol ester-induced MUC5AC mucin production and gene expression from human airway epithelial cells.

In this study, the effects of oleanolic acid and ursolic acid on MUC5AC mucin production and gene expression induced by epidermal growth factor (EGF) and phorbol 12-myristate 13-acetate (PMA) from human airway epithelial cells were investigated. Confluent NCI-H292 cells were pretreated with each agent for 30 min and then stimulated with EGF and PMA for 24 h, respectively. MUC5AC mucin gene expression and mucin protein production were measured by RT-PCR and ELISA. Oleanolic acid and ursolic acid were found to inhibit the production of MUC5AC mucin protein induced by EGF and PMA, and both compounds also inhibited the expression of MUC5AC mucin gene induced by EGF and PMA. These results suggest that oleanolic acid and ursolic acid can regulate mucin gene expression, and production of mucin protein, by directly acting on airway epithelial cells.