The antimycotic drugs itraconazole and terbinafine hydrochloride induce the production of human β-defensin-3 in human keratinocytes

Abstract

The antimicrobial peptide human β-defensin-3 (hBD-3) is produced by epidermal keratinocytes, and exhibits broad killing activity against bacteria or fungi. Prostaglandin D 2 enhances hBD-3 production in human keratinocytes by stimulating a transcription factor, activator protein-1 via chemoattractant receptor-homologous molecule expressed on T helper 2 cells (CRTH2). Prostaglandin H 2, a precursor of prostaglandin D 2 can be converted to thromboxane A 2. Certain antimycotic drugs act on keratinocytes and modulate their production of chemokines. In this in vitro study, we examined the effects of antimycotics on hBD-3 production in human keratinocytes. Antimycotics itraconazole and terbinafine hydrochloride increased hBD-3 secretion and mRNA levels in parallel to the enhanced activity of activator protein-1, expression and phosphorylation of activator protein-1 component, c-Fos, but fluconazole was ineffective. These effects were abrogated by CRTH2 antagonist. Itraconazole and terbinafine hydrochloride increased prostaglandin D 2 release from keratinocytes and reduced the release of thromboxane B 2, a thromboxane A 2 metabolite. The conditioned medium from itraconazole or terbinafine hydrochloride-treated keratinocytes inhibited the growth of Candida albicans dependently on hBD-3. These results suggest that itraconazole and terbinafine hydrochloride may enhance c-Fos expression and phosphorylation, activator protein-1 activity and hBD-3 production by increasing prostaglandin D 2 release from keratinocytes. These antimycotic drugs may suppress thromboxane A 2 synthesis and redirect the conversion of prostaglandin H 2 towards prostaglandin D 2. The induction of hBD-3 in keratinocytes is another possible mechanism for the antimycrobial effects of these drugs, which may augment the cutaneous defense activity against infection.