Pharmacological correction of cognitive dysfunctions in animals
Abstract
Cognitive dysfunction in animals, particularly in aging domestic companions, is an increasingly important area of study in v e terinary medicine. The pathology is often compared to neurodegenerative conditions in humans, such as Alzheimer’s disease, due to similar clinical and neuropathological features. Affected animals display signs like memory impairment, disorientation, changes in social interaction, and anxiety-related behaviors. The growing need to improve the quality of life in these animals and the poss i bility to use them as a model for human diseases highlights the importance of effective research in this area. Cholinesterase inhib i tors such as donepezil enhance cholinergic transmission in the central nervous system, improving memory, learning ability, and overall cognitive function. Donepezil has demonstrated clinical benefits in aging dogs, particularly in later stages of cognitive d e cline. Its pharmacological profile includes acetylcholinesterase inhibition, reduction of neuroinflammation, enhancement of syna p tic plasticity, and support for neuronal connectivity. Innovative delivery systems, such as injectable microspheres, aim to prolong its therapeutic effects and minimize adverse reactions. Central nervous system stimulants like methylphenidate increase catecholam i nergic activity and improve functions related to attention, working memory, and executive control. However, their clinical use requires caution due to possible side effects including anxiety, restlessness, sleep disturbances, and increased oxidative stress. M e mantine, an N-methyl-D-aspartate receptor antagonist, offers neuroprotection by mitigating excitotoxicity and inflammation, with promising effects in both ischemic and degenerative conditions. Its stable pharmacokinetic profile and emerging transdermal fo r mulations support wider and safer use in clinical settings. Nootropic agents such as piracetam and oxiracetam support cerebral metabolism and enhance neural adaptability under conditions of hypoxia and oxidative stress. Oxiracetam has been shown to i m prove spatial learning, reduce ischemic brain injury, restore blood-brain barrier integrity, and increase cerebral circulation, combi n ing cognitive and neuroprotective effects. Selegiline, a selective monoamine oxidase B inhibitor, exerts antioxidant and neurotrop h ic effects by modulating dopaminergic pathways, enhancing motivation, reducing anxiety, and promoting the expression of brain-derived neurotrophic factor and nerve growth factor, which support cognitive restoration. Additional compounds, including antiox i dants (vitamins C and E, coenzyme Q 10 ), mitochondrial cofactors (taurine, L-carnitine, alpha-lipoic acid), and polyunsaturated fatty acids like docosahexaenoic acid, contribute to the maintenance of neuronal function, membrane stability, and resistance to oxidative damage. Used individually or in combination, these agents hold potential for slowing cognitive decline and improving quality of life in aging companion animals. Overall, pharmacological correction of cognitive dysfunction in animals holds promise for i m proving animal welfare and may offer translational insights relevant to human medicine.References
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