Protective effects of glycerol and xylitol in keratinocytes exposed to hyperosmotic stress

Abstract

Purpose: Our goal was to study whether glycerol and xylitol provide protection against osmotic stress in keratinocytes.

Methods: The experiments were performed on HaCaT keratinocytes. Hyperosmotic stress was induced by the addition of sorbitol (450, 500 and 600 mOsm). Both polyols were applied at two different concentrations (glycerol: 0.027% and 0.27%, xylitol: 0.045% and 0.45%). Cellular viability and cytotoxicity were assessed, intracellular Ca²⁺ concentration was measured, and the RNA expression of inflammatory cytokines was determined by means of PCR. Differences among groups were analyzed with one-way ANOVA and Holm-Sidak post-hoc test. When the normality test failed, Kruskal–Wallis one-way analysis of variance on ranks, followed by Dunn’s method for pairwise multiple comparison was performed.

Results: The higher concentrations of the polyols were effective. Glycerol ameliorated the cellular viability while xylitol prevented the rapid Ca²⁺ signal. Both polyols suppressed the expression of IL-1α but only glycerol decreased the expression of IL-1β and NFAT5.

Conclusions: Glycerol and xylitol protect keratinocytes against osmotic stress. Despite their similar chemical structure, the effect of these polyols displayed differences. Hence, joint application of glycerol and xylitol may be a useful therapeutic approach for different skin disorders.

Keywords:

• hyperosmotic stress
• glycerol
• xylitol
• intracellular calcium concentration

Acknowledgment

The authors are grateful to the assistants for their valuable contribution to the work.

Disclosure

The authors report no conflicts of interest in this work.