Invest Ophthalmol Vis Sci. 2026 May 1;67(5):71. doi: 10.1167/iovs.67.5.71.
ABSTRACT
PURPOSE: We previously demonstrated that intracellular oxidative stress reduces corneal endothelial cells in Tet-mev-1 mice that genetically overproduce mitochondrial superoxide anions. This study aimed to elucidate the physiological processes underlying oxidative stress-induced corneal endothelial cell loss.
METHODS: Primary cultures of mouse corneal endothelial cells were established. Intracellular lipid droplets were detected using Lipi-Green, and autophagosomes in live cells were visualized using DAPGreen. Autophagy was assessed by immunostaining and Western blot analysis using microtubule-associated protein 1 light chain 3 (LC3). Furthermore, autophagic flux was evaluated by LC3 and p62/SQSTM1 levels with bafilomycin A1. DNA damage was assessed by γH2AX pSer139 immunostaining.
RESULTS: Corneal endothelial cells formed a paving stone-like monolayer and expressed endothelial markers. Tet-mev-1 cells, which were mitochondrial oxidative stress-overproduced mouse cells, exhibited senescent-like cells with abnormal lipid droplet accumulation, vacuolation, and DNA damage compared with wild-type cells. Quantitative analyses confirmed increased lipid droplets, autophagosomes, DNA damage, and vacuolated cells. In young Tet-mev-1 cells, autophagy-related responses were relatively preserved under oxidative stress conditions. In contrast, aged Tet-mev-1 cells showed attenuated responses to lysosomal inhibition, suggesting a decline in autophagic degradation capacity with premature aging by oxidative stress.
CONCLUSIONS: Intracellular oxidative stress is associated with enhanced autophagic activity in young corneal endothelial cells, whereas progressive endothelial cell loss with aging is accompanied by alterations in autophagy-related processes. This shift contributes to the accumulation of lipid droplets, vacuolations, and DNA damage. These findings suggest that maintenance of lipid homeostasis through autophagy-related pathways may play an important role in delaying age-related corneal endothelial dysfunction.
PMID:42206946 | DOI:10.1167/iovs.67.5.71