Age-related pathomorphological changes in the brain of non-human primates

The global aging of the population and the rising prevalence of neurodegenerative disorders, such as Alzheimer’s and Parkinson’s diseases, pose a significant challenge to healthcare systems in developing countries. Non-human primates are regarded as the most relevant natural model for studying age-related neurodegeneration due to their high degree of similarity to humans in terms of brain anatomy, genetics, and cognitive functions. In the present study, brain specimens from 21 aged individuals (20—34 years old) representing several primate species were analyzed. Macroscopic examination revealed atrophy of the occipital lobes and ventriculomegaly. Histopathological assessment demonstrated consistent age-associated alterations across all specimens, including vascular sclerosis and hyalinosis, reduced neuronal density in the cerebral cortex, leukoaraiosis, vacuolar degeneration, and accumulation of lipofuscin — the so-called «aging pigment». These pathological features closely resemble those observed in human brain aging and neurodegenerative conditions. Therefore, aged non-human primates represent a valuable biological resource for investigating the pathogenesis of spontaneous neurodegeneration and for developing therapeutic strategies with high translational relevance to clinical medicine. This study constitutes the first systematic description in Russia of age-related neuropathological changes in non-human primates and paves the way for establishing translational models of neurodegenerative diseases based on natural aging.