Suppression of IL-1beta-induced MUC5AC Gene Expression by Ginkgo biloba Extract(EGb 761) in Human Airway Epithelial Cells

ABSTRACT

BACKGROUND AND OBJECTIVES: The purpose of this study is to investigate whether Ginkgo biloba extract (EGb 761) can suppress IL-1beta-induced MUC5AC gene expression in NCI-H292 human airway epithelial cells and to discover what its possible mechanism is. MATERIALS AND METHODS: NCI-H292 human pulmonary mucoepidermoid carcinoma cell line was used. MUC5AC mRNA and protein were measured using the RT-PCR and Western blot analysis. The activation of mitogen activated protein kinases (MAPKs) were determined by means of the Western blot analysis. RESULTS: MUC5AC was induced by treating the NCI-H292 cells with 10 ng/ml of IL-1beta for 24 hours. A pre-treatment of 200 microgram/ml of EGb 761 significantly suppressed the IL-1beta induced MUC5AC expression. The inhibition of MUC5AC gene expression by EGb 761 was noted to be suppressed via both the extracellular signal-regulated kinase (ERK) and the p38 MAPK pathways in a kinase-specific inhibitor study. CONCLUSION: EGb 761 suppresses IL-1beta-induced MUC5AC gene expression in the human airway epithelial cells. Therefore, it may be considered as a possible anti-hypersecretory agent.