Abstract
Introduction. Microglia initiate and play a key role in neuroinflammation, which is currently considered one of the main mechanisms of neurodegeneration in Alzheimer’s disease. The aim of this study was to analyze the morphofunctional characteristics of microglia in the hippocampus and cerebral cortex of 5xFAD mice of different ages.
Material and methods. Brain samples from 5xFAD mice aged 4 months (n=3) and 8 months (n=3) served as the study material. Brain samples from C57BL6/SJL mice (n=3) served as a control. For the simultaneous detection of microglia and amyloid plaques, an original methodological approach was used. This approach involves an immunohistochemical reaction for the microglia marker protein Iba1, followed by staining the sections with the phthalocyanine dye Alcian blue to identify amyloid plaques. The nonparametric Kruskal–Wallis test and Dunn’s post hoc test were used to compare groups. Differences between groups were considered significant at p<0.05.
Results. Microglial activation, which increases with age, is observed in the hippocampus and cerebral cortex of 5xFAD mice. The area occupied by microglia is statistically significantly higher in 8-month-old 5xFAD mice compared to controls. All amyloid plaques detected using Alcian blue are surrounded by activated microglia. Furthermore, in the cortex and hippocampus of 5xFAD mice, groups of microglial cells are present that are not associated with amyloid deposits but show signs of activation.
Conclusion. The study revealed new aspects of age-related pathology in the 5xFAD model associated with the structural and functional status of microglia in the hippocampus and cerebral cortex.
Authors and affiliations
https://elibrary.ru/ahzqaz
V.V. Guselnikova, D.A. Sufieva, D.E. Korzhevskii
Federal State Budgetary Scientific Institution «Institute of Experimental Medicine» (FSBSI «IEM»),
Academician Pavlov Street, 12, Saint-Petersburg, 197022, Russian Federation
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