[Reduction of lipid peroxidation and apoptosis in corneal endothelial cells by vitamin A].

PURPOSE

The goal of this study was to determine the effects of lipid peroxidation-mediated toxicity of iron ions on corneal endothelial cells leading to apoptosis.

METHODS

Murine corneal endothelial cells were maintained in tissue culture medium supplemented with free iron ions, known to lead to increased lipid peroxidation. Retinoic acid in the cell supernatant and cytoplasm of these cells was determined using HPLC. The rate of apoptosis was assessed by quantification of caspase-3-like activity. The lipid peroxidation was measured using the malondialdehyde method. Supplementation of retinoic acid was tested in the setting of apoptosis.

RESULTS

Free iron ions led to a rapid loss of retinoic acid in the supernatant and the corneal endothelial cells. This was correlated with rising levels of malondialdehyde following oxidative stress and increased apoptosis. Supplementation of retinoic acid alone significantly reduced oxidative stress and apoptosis in the respective cells.

CONCLUSION

In this study the authors present a novel in vitro model to test the direct influence of pro-oxidative species on corneal endothelial cells. The authors also prove that supplementing corneal endothelial cells with retinoic acid sufficiently prevents free radical injury and apoptosis.