Nuclear factor-kappa B activation in silica-induced interleukin 8 production by human bronchial epithelial cells

Recent studies indicate that interleukin 8 (IL-8) plays an important role in interstitial lung diseases including silica-induced lung inflammation. To investigate the regulation of IL-8 expression and production in human bronchial epithelial cells, we examined the effects of silica on NF-kappa B activation, Human bronchial epithelial cell line BET-1A was cultured with hormonally defined Ham's F12 medium. The administration of silica induced IL-8 production in BET-1A dose-dependently and time-dependently. Northern blot analysis demonstrated that silica upregulated IL-8 expression in BET-1A, Moreover, electrophoretic mobility shift assays revealed that NF-kappa B activation occurred in the presence of silica, which was inhibited by antioxidants such as N-acetylcysteine (NAC), These data suggest that reactive oxygen species may be involved in the activation of NF-kappa B induced by silica, (C) 2000 Academic Press.