The Presence of Guttae in Fuchs Endothelial Corneal Dystrophy Explants Correlates With Cellular Markers of Disease Progression.

Purpose: Fuchs endothelial corneal dystrophy (FECD) is characterized by an accelerated depletion of corneal endothelial cells. There is growing evidence that mitochondrial exhaustion is central in the pathology. Indeed, endothelial cells loss in FECD forces the remaining cells to increase their mitochondrial activity, leading to mitochondrial exhaustion. This generates oxidation, mitochondrial damage, and apoptosis, fueling a vicious cycle of cells' depletion. This depletion ultimately causes corneal edema and irreversible loss of transparency and vision. Concurrently to endothelial cells loss, the formation of extracellular mass called guttae on the Descemet's membrane, is a hallmark of FECD. The pathology origins at the center of the cornea and progress outward, like the appearance of guttae. Methods: Using corneal endothelial explants from patients with late-stage FECD at the time of their corneal transplantation, we correlated mitochondrial markers (mitochondrial mass, potential, and calcium) and the level of oxidative stress and apoptotic cells, with the area taken by guttae. The different markers have been analyzed using fluorescent-specific probes and microscopic analysis. Results: We observed a positive correlation between the presence of guttae and the level of mitochondrial calcium and apoptotic cells. We found a negative correlation between the presence of guttae and the level of mitochondrial mass, membrane potential, and oxidative stress. Conclusions: Taken together, these results show that the presence of guttae is correlated with negative outcome in the mitochondrial health, oxidative status, and survival of nearby endothelial cells. This study provides insight on FECD etiology that could lead to treatment targeting mitochondrial stress and guttae.