Mature and old male Wistar rats’ internal organs morphology by aluminum chloride prolonged consumption

One of the key features of aging is the formation of the age-associated secretory phenotype i.e. SASP. It is characterized by the emergence of a persistent systemic low-level pro-inflammatory background, or inflammaging, and a shift in the balance of secretion of pro- and anti-inflammatory mediators towards pro-inflammatory ones with the formation of reactive oxygen species. Their excess leads to oxidative stress and is one of the factors in the initiation and progression of age-associated diseases, including Alzheimer's disease. Its pathogenesis has not been sufficiently studied, including due to the lack of relevant experimental models. Previously, we showed that long-term consumption of aluminum chloride (AlCl3) initiates molecular biological changes characteristic of neurodegenerative processes, but only in old animals. However, the systemic effects of AlCl3 on various organs and systems are extremely poorly described in the literature and without taking into account age-related changes. The aim of the work was to evaluate morphological changes in internal organs of mature and old male Wistar rats consuming AlCl3 at a dose of 100 mg/kg/day for 60 days. AlCl3 at a dose of 100 mg/kg/day for 60 days in mature and old rats does not lead to pathomorphological changes in the liver, kidneys, thymus and spleen. In the mature rats of the experimental group, an increase in the relative number of binuclear hepatocytes was observed compared to the control mature animals, while in old rats consuming AlCl3, the relative number of non-epithelial cells was higher than in the comparison group. In both groups, a decrease in the volume fractions of light centers of the lymphoid nodules of the spleen was observed in old animals. Thus, consumption of aluminum chloride at a dose of 100 mg/kg/day for 60 days does not lead to toxic damage to the kidneys, liver and organs of the immune system, so the developed model can be used to study neurodegenerative processes.