Citicoline in Ophthalmological Neurodegenerative Disease: A Comprehensive Review

Cytidine 5'-diphosphocholine has been widely studied in systemic neurodegenerative diseases, like Alzheimer's disease, Parkinson's disease, and brain ischemia. The rationale for the use of citicoline in ophthalmological neurodegenerative diseases, including glaucoma, anterior ischemic optic neuropathy, and diabetic retinopathy, is founded on its multifactorial mechanism of action and the involvement in several metabolic pathways, including phospholipid homeostasis, mitochondrial dynamics, as well as cholinergic and dopaminergic transmission, all being involved in the complexity of the visual transmission. This narrative review is aimed at reporting both pre-clinical data regarding the involvement of citicoline in such metabolic pathways (including new insights about its role in the intracellular proteostasis through an interaction with the proteasome) and its effects on clinical psychophysical, electrophysiological, and morphological outcomes following its use in ophthalmological neurodegenerative diseases (including the results of the most recent prospective randomized clinical trials).