Retinal neurodegeneration in a mouse model of green-light-induced myopia

Purpose: To determine the retinal neurodegeneration occurring in mice with green-light-induced myopia. Methods: Four-week-old mice were raised under white or green light (peak at 510 nm). Refraction and axial length (AL) were measured before and after eight weeks of illumination treatment. TUNEL staining, electron microscopy and the Visual Cliff test were performed to identify the conditions of retinal degeneration. The distinct protein signatures of retina tissues were quantified by mass spectrometry (MS) -based proteomics, and analyzed by Gene Set Enrichment Analysis (GSEA), Kyoto Encyclopedia of Genes and Genomes (KEGG) anno-tation and STRING database. Western blot was used to detect the expression of the specific protein. Results: Green-light-induced myopia was developed in mice after eight weeks of illumination treatment. Apoptosis and the abnormality in ultrastructure and visual function of mice exposed to green light were found through morphological and behavioral experiment, indicating retinal degeneration. The altered proteome was associated with Human Phenotype Ontology (HPO) annotations sets of 'abnormality of visual evoked potentials' and 'neuronal loss in central nervous system'. KEGG annotation demonstrated the altered pathway of the dopaminergic synapse in the myopic mice. STRING database was utilized with an effort to identify the molecular pathways within, and dysregulation of mitochondrial metabolism was revealed. Conclusions: Overall, our study revealed molecular differences and pathways underlying retinal degeneration in the mouse model of green-light-induced myopia. These findings might provide insights into further research into myopia prevention and control.