Cranberry Polyphenols Suppress Candida albicans-Induced Inflammatory Response in Epithelial Cells

Objective: Oral candidosis is an opportunistic infection of the oral cavity caused by an overgrowth of Candida species, the most common being Candida albicans. Recently, cranberry polyphenols have received considerable attention for their potential oral health benefits. The aim of this study was to evaluate the capacity of a proanthocyanidin-enriched cranberry fraction to reduce the inflammatory response of oral epithelial cells infected with C. albicans. Methods: The human oral epithelial cell line GMSM-K was pre-treated (2 h) with the cranberry fraction prior to being infected with C. albicans (live and heat-inactivated) at various concentrations. Secretion of the pro-inflammatory cytokine interleukin-6 (IL-6) and the chemokine interleukin-8 (IL-8) was quantified by enzyme-linked immunosorbent assays. Results: Live C. albicans induced a dose- and time-dependent secretion of both IL-6 and IL-8 by epithelial cells. The inflammatory response induced by heat-inactivated C. albicans was much less pronounced. The IL-6 and IL-8 responses of epithelial cells infected with C. albicans were significantly reduced by a pre-treatment with the proanthocyanidin-enriched cranberry fraction at non-cytotoxic concentrations. An almost complete inhibition was obtained when the cranberry fraction was used at 100 µg/ml. Conclusions: This study suggests that cranberry polyphenols may offer perspectives for the development of a new therapeutic approach for the prevention and treatment of oral candidosis. This study was supported by The Cranberry Institute.