Antioxidant MitoQ increases viability of human corneal endothelial cells with congenital hereditary endothelial dystrophy-associated SLC4A11 mutations.

Abstract

Purpose: To assess the impact of MitoQ, a mitochondria-targeted antioxidant, on viability of human corneal endothelial cell (hCEnC) lines expressing SLC4A11 mutations associated with congenital hereditary endothelial dystrophy (CHED) and Fuchs endothelial corneal dystrophy type 4 (FECD4).

Methods: SLC4A11 wildtype (SLC4A11^WT) and mutant (SLC4A11^MU) hCEnC lines were created to express either SLC4A11 variant 2 (V2) or variant 3 (V3) by stable transduction of SLC4A11^-/- hCEnC-21T with lentiviruses containing either SLC4A11^WT or one of the following mutations: V2 (V3) mutants c.374 G>A (c.326 G>A) (CHED), c.1813C>T (c.1765C>T) (CHED), c.2263C>T (c.2215C>T) (CHED), or c.2224 G>A (c.2176 G>A) (FECD4). A SLC4A11^{-/- empty} hCEnC line was created by stable transduction of SLC4A11^-/- hCEnC-21T with an empty lentiviral plasmid. Cell viability was measured by exposing MitoQ treated and untreated cells to oxidative stress agent tert-butyl hydroperoxide (tBH) followed by performing XTT assays and spectrophotometry.

Results: SLC4A11^{-/- empty}, SLC4A11 V2^WT, and SLC4A11 V3^WT hCEnC exposed to ≤0.01 μM MitoQ retained over 90% of the viability of untreated SLC4A11^{-/- empty} hCEnC. When treated with MitoQ, SLC4A11^{-/- empty} was able to demonstrate partial restoration of cell viability. All CHED-associated mutant hCEnC lines treated with 0.01 μM MitoQ demonstrated increased viability compared to untreated following exposure to tBH. The FECD4-associated mutant hCEnC line treated with 0.01 μM MitoQ showed no significant increase in cell viability compared to untreated following exposure to tBH.

Conclusions: Media supplementation with antioxidant MitoQ has beneficial effects on cell viability in hCEnC harboring CHED-associated SLC4A11 mutations following exposure to tBH-induced oxidative stress.