Abstract
PurposeTo evaluate the presence and concentration of citicoline and its metabolites (choline, cytidine and uridine) in the vitreous body in human eyes after topical application of an ophthalmic solution of citicoline 2%, in vivo.MethodsTwenty-one subjects affected by epiretinal membrane with surgical indication for pars-plana vitrectomy underwent treatment with 1 drop 3 times/day of a solution of citicoline 2%, 0.2% high molecular weight hyaluronic acid and 0.01% benzalkonium chloride (OMK1, Omikron Italia s.r.l., Rome, Italy) 14 days before surgery and 2 hours prior to surgery. Five additional patients served as controls and received an OMK1 vehicle solution without citicoline. The vitreous samples were taken at the beginning of the pars-plana vitrectomy and analyzed for qualitative/quantitative determination of vitreous concentration of citicoline and its metabolites by means of high performance liquid chromatography.ResultsThe overall mean concentration of citicoline in patients treated with citicoline 2% solution was 406.72 ± 52.99 μg/mL, while the mean concentration of choline, cytidine and uridine was 180.88 ± 41.49 μg/mL, 44.45 ± 10.19 μg/mL and 330.41 ± 75.8 μg/mL, respectively. The concentration of citicoline in phakic eyes (n = 13, 366.61 ± 129.61 μg/mL) was lower compared to that found in pseudophakic eyes (n = 8, 435.89 ± 131.42 μg/mL) and the difference was not statistically significant. The concentration of citicoline in the control eyes was 45.66 ± 26.36 μg/mL, while the concentration of choline, cytidine and uridine were 17.21 ± 9.93 μg/mL, 6.24 ± 3.6 μg/mL and 172.80 ± 99.76 μg/mL, respectively.ConclusionCiticoline can reach the human vitreous in high concentration when administered in ophthalmic solution. This evidence contributes to the build-up of the pyramid of the evidences required for determining the role of citicoline administered in ophthalmic formulation in retinal and optic nerve neurodegenerative diseases.
Highlights
Citicoline is a mononucleotide composed by ribose, pyrophosphate, cytosine and choline
Citicoline can reach the human vitreous in high concentration when administered in ophthalmic solution
This evidence contributes to the build-up of the pyramid of the evidences required for determining the role of citicoline administered in ophthalmic formulation in retinal and optic nerve neurodegenerative diseases
Summary
Citicoline (cytidine-5’-diphosphocholine or CDP-Choline) is a mononucleotide composed by ribose, pyrophosphate, cytosine and choline. It is considered an intermediate in the biosynthesis of phosphatidylcholine (PDC), one of the most important phospholipids of the cell membranes, and the precursor of the neurotransmitter acetylcholine in the central nervous system [1]. Citicoline increases tyrosine hydroxylase activity and inhibits dopamine reuptake increasing brain neurotransmitters like dopamine, noradrenaline and serotonin [2]. Citicoline is quickly metabolized to choline and cytidine. Plasmatic cytidine is deaminated by cytidine deaminase to uridine. Uridine is the precursor of uridine triphosphate in the brain, cytidine triphosphate at neuronal level and citicoline [3]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
