Effect of trehalose on protection of desiccation-induced human corneal epithelial cell damage and lubrication of contact lens surfaces

Abstract

Purpose: To investigate the effect of trehalose on protection of human corneal epithelial cells from desiccation-induced damage in vitro, and lubricity of contact lenses.

Methods: Near confluent human corneal epithelial cells were treated with trehalose with various concentrations (0.5%- 2.0%) for 30 minutes. After the treatment, the medium was removed and the cells were left for drying for 20 min. The physiological state of the cells was evaluated through mitochondrial activity using a MTT assay, and staining for apoptosis and necrosis using Hoechst (for total cells); Annexin V (for apoptotic cells); and PI (for necrotic cells) and confocal microscopic evaluation. Kinetic coefficient of friction of two silicone hydrogel contact lenses was measured after soaking in trehalose (0.8% in PBS) or PBS solutions for 24 hours.

Results: Desiccation caused 3-fold reduction (p = 0.0001) in cellular mitochondrial activity compared to the cells not under desiccation. Treatment of cells with trehalose (at concentration of 0.6%- 2.0%) prior to the desiccation exposure minimized the above deteriorating effect on cells with more than 2-fold recovery in mitochondrial activity (all p < 0.001) and 2-fold reduction in percentage of damaged cells (p < 0.05) compared to the PBS control. Contact lenses soaked in trehalose showed lower coefficient of friction (0.0090±0.0002 and 0.0118±0.0008 for Clariti 1Day and FND, respectively) than those of presoaked in PBS (0.0124±0.0025 and 0.0132±0.0017 for Clariti 1Day and FND, respectively).

Conclusions: Trehalose protects HCLE cells from desiccation-induced cell damage/death and it may potentially improve contact lens lubrication.

Keywords: 426 apoptosis/cell death • 477 contact lens • 482 cornea: epithelium