**Background**
Neurological disorders and sensory impairments, such as hearing loss, are often driven by oxidative stress, excitotoxicity, and the activation of apoptotic pathways. A critical component in maintaining cellular integrity is phosphatidylcholine, a primary phospholipid of cell membranes. The synthesis and maintenance of these membranes are essential for neuronal survival and function. When cell membranes are compromised by reactive oxygen species (ROS) or neurotoxic insults, apoptosis is triggered, leading to irreversible tissue damage. Consequently, identifying agents that can inhibit ROS and suppress apoptosis is vital for developing therapeutic strategies for neurodegenerative conditions. In this context, we will introduce an endogenous intermediate in the synthesis of phosphatidylcholine – Citicoline.
**Definition**
Citicoline is a human endogenous metabolite and microbial metabolite that acts as a precursor for cell membrane synthesis. It functions by inhibiting reactive oxygen species (ROS) and suppressing apoptosis, specifically targeting the activity of Caspase-3, Caspase-8, and Caspase-9.
**In Vitro and In Vivo Studies**
The Citicoline biological activity has been extensively evaluated across various models of cellular injury. Citicoline in vitro studies demonstrate that concentrations of 1-100 μM for 24 h significantly increase the viability of rat retinal cells following glutamate-induced excitotoxicity, showing synergistic effects when combined with Tramiprosate. Furthermore, Citicoline (100 μM) administered 24 h before glutamate treatment and 30 min before high glucose (HG) treatment reduces proapoptotic effects associated with neuroretinal degeneration. In auditory research, Citicoline (100 μM, 36-48 h) attenuates oxidative stress and reduces apoptosis in mice cochlear hair cells (HCs) and HEI-OC-1 cells after Neomycin exposure. This is achieved by decreasing the mRNA and protein levels of pro-apoptotic factors such as Bax, Casp3, Casp8, and Casp9, while increasing the anti-apoptotic factor Bcl-2.
Regarding Citicoline In Vivo applications, the compound has shown significant neuroprotective properties in seizure models. In male C57Bl/6 mice, intraperitoneal administration of Citicoline (500-1000 mg/kg; 1 h before test) produces a pronounced anticonvulsant effect against pentylenetetrazole-induced convulsions. Specifically, a dose of 1000 mg/kg was found to be the most effective in increasing the threshold of clonic and tonic seizures. For researchers requiring detailed Citicoline technical information, these results highlight its potential in mitigating excitotoxic and oxidative damage. In conclusion, Citicoline is a potent cytoprotective agent that supports membrane synthesis and inhibits apoptosis in neurological and auditory systems.
Keywords
Citicoline, 987-78-0, Cytidine diphosphate-choline, CDP-Choline, Cytidine 5′-diphosphocholine, Apoptosis, Endogenous Metabolite, Reactive Oxygen Species (ROS), Caspase, reactive oxygen species, neurological, hearing loss, Inhibitor, inhibitor, inhibit
References
[1] Davinelli S, et al. Cytoprotective Effects of Citicoline and Homotaurine against Glutamate and High Glucose Neurotoxicity in Primary Cultured Retinal Cells. Oxid Med Cell Longev. 2017;2017:2825703.
[2] Karpova MN, et al. Increase of the seizure threshold in C57BL/6 mice after citicoline administration. Bull Exp Biol Med. 2015 Jan;158(3):315-7.
[3] Zhong Z, et al. Citicoline Protects Auditory Hair Cells Against Neomycin-Induced Damage. Front Cell Dev Biol. 2020 Aug 31;8:712.