The Effect of SkQ1 on the Oxidative Stress and Inflammatory Responses in Corneal Endothelial Cells During Ex Vivo Expansion

Abstract

Purpose: The purpose of this study was to characterize the oxidative stress and inflammatory responses in ex vivo corneal endothelial cells (evCEnC) during expansion and assess the impact of SkQ1, an antioxidant and anti-inflammatory compound, on measures of oxidative stress and inflammation. Methods: A CEnC line (HCEnC-21T) was cultured in media supplemented with varying SkQ1 concentrations to determine the optimal SkQ1 dose range of toxicity and protective effect on CEnC exposed to acute oxidative stress. The impact of SkQ1 treatment on intracellular free radical (IFR) levels, NRF2-mediated oxidative stress response, and NFkB-mediated inflammatory response was determined at each passage of evCEnC isolated from donor corneas and cultured in SkQ1-supplemented and untreated media. Results: HCEnC-21T cultured in media supplemented with ≤250 nM SkQ1 retained over 95% cell viability compared with untreated cells. SkQ1 provided oxidative stress protection to HCEnC-21T in a dose-dependent manner up to 500 nM. In evCEnC, 50 nM and 250 nM SkQ1 supplementation significantly reduced IFR levels across passages 0 to 3 (P-values of 0.015 and 0.023, respectively) and 50 nM SkQ1 supplementation led to decreased levels of active NRF2 in evCEnC at passage 2. However, media supplementation with SkQ1 (50 nM and 250 nM) did not alter NFkB activation at any passage. Conclusions: SkQ1 media supplementation provides oxidative stress protection to HCEnC-21T in a dose-dependent manner and decreases IFR levels and NRF2 activation in evCEnC during expansion at concentrations that do not negatively affect CEnC viability. These findings indicate that SkQ1 supplementation may increase the expansion potential of evCEnC.