title: Apigenin Inhibits Tumor Necrosis Factor-α-Induced Production and Gene Expression of Mucin through Regulating Nuclear Factor-Kappa B Signaling Pathway in Airway Epithelial Cells.
abstract: In the present study, we investigated whether apigenin significantly affects tumor necrosis factor-α (TNF-α)-induced production and gene expression of MUC5AC mucin in airway epithelial cells. Confluent NCI-H292 cells were pretreated with apigenin for 30 min and then stimulated with TNF-α for 24 h or the indicated periods. The MUC5AC mucin gene expression and mucin protein production were measured by reverse transcription - polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. Apigenin significantly inhibited MUC5AC mucin production and down-regulated MUC5AC gene expression induced by TNF-α in NCI-H292 cells. To elucidate the action mechanism of apigenin, effect of apigenin on TNF-α-induced nuclear factor kappa B (NF-κB) signaling pathway was also investigated by western blot analysis. Apigenin inhibited NF-κB activation induced by TNF-α. Inhibition of inhibitory kappa B kinase (IKK) by apigenin led to the suppression of inhibitory kappa B alpha (IκBα) phosphorylation and degradation, p65 nuclear translocation. This, in turn, led to the down-regulation of MUC5AC protein production in NCI-H292 cells. Apigenin also has an influence on upstream signaling of IKK because it inhibited the expression of adaptor protein, receptor interacting protein 1 (RIP1). These results suggest that apigenin can regulate the production and gene expression of mucin through regulating NF-κB signaling pathway in airway epithelial cells.
authors.affiliation: Department of Pharmacology, School of Medicine, Chungnam National University, Daejeon 301-131, Republic of Korea.
authors.forename: Hyo-Seok
authors.initials: HS
authors.lastname: Seo
authors.affiliation: Department of Pharmacology, School of Medicine, Chungnam National University, Daejeon 301-131, Republic of Korea.
authors.forename: Mohamed Asaduzzaman
authors.initials: MA
authors.lastname: Sikder
authors.affiliation: Department of Pharmacology, School of Medicine, Chungnam National University, Daejeon 301-131, Republic of Korea.
authors.forename: Hyun Jae
authors.initials: HJ
authors.lastname: Lee
authors.affiliation: Department of Pharmacology, School of Medicine, Chungnam National University, Daejeon 301-131, Republic of Korea.
authors.forename: Jiho
authors.initials: J
authors.lastname: Ryu
authors.affiliation: Department of Pharmacology, School of Medicine, Chungnam National University, Daejeon 301-131, Republic of Korea.
authors.forename: Choong Jae
authors.initials: CJ
authors.lastname: Lee
keywords: Airway; Apigenin; Mucin