Influence of Fructose-Fat Diet on Age-Related Morphological Changes in Rats Visual Cortex

The aim was to study the morphological changes in the visual cortex of the brain in young and old rats treated with a fructose-fat diet (FFD). Material and methods . The study was carried out on male Wistar rats, divided into the following groups: 1st (n=14) – intact 6-month-old rats received a standard diet; 2nd (n=14) – 6-month-old rats received a fructose-fat diet (FFD) for 90 days (from 3 months of age); 3rd (n = 14) – intact 18-month-old rats received a standard diet; 4th (n = 14) – 18-month-old rats received the FFD for 90 days (from 15 months of age). Histological sections were Nissl stained. Immunohistochemical reaction was performed to detect the expression of vascular endothelial growth factor (VEGF). In layers II, IV and V of the primary visual cortex, the percentage of normochromic and altered neurons and the number of gliocytes in 1 mm2 of section were calculated. Differences between groups were determined using the Kruskal–Wallis multiple comparison test. Results . In Morphological changes in the visual cortex in 18-month-old rats were most pronounced in layers IV and V and, in addition to reversible neuronal disorders, were characterized by total chromatolysis and vacuolization of the cytoplasm. In 6-month-old rats on a FFD, the most pronounced increase in hyperchromic neurons with shrinkage was observed in layer IV. In 18-month-old animals, pathological changes in neurocytes were found in all studied layers of the primary visual cortex, and pronounced signs of neuronophagia and gliosis were noted. In 18-month-old intact rats and 6- and 18-month-old rats on a FFD, vascular congestion and perivascular edema and pronounced expression of VEGF were detected. Conclusion . FFD enhances age-related changes in the visual cortex of rats, manifested by vascular disorders, degenerative changes in neurons and glial hyperreactivity.