PhD Scientific Days 2025

Poster Session I. - I: Theoretical and Translational Medicine

The Assessment of Morphological Changes in the Liver, Thymus, and Spleen of Adult and Old Wistar Rats Due to Chronic Expousure to AlCl3

Name of the presenter

Sentyabreva Alexandra

Institute/workplace of the presenter

Avtsyn Research Institute of Human Morphology of «Petrovsky National Research Centre of Surgery», Moscow, Russia

Authors

Sentyabreva Alexandra¹, Melnikova Ekaterina A.², Kosyreva Anna M.²

1: Avtsyn Research Institute of Human Morphology of «Petrovsky National Research Centre of Surgery», Moscow, Russia
2: Research Institute of Molecular and Cellular Medicine, RUDN University named after Patrice Lumumba, Moscow, Russia

Text of the abstract

Introduction. Aging is accompanied with an excess of pro-inflammatory mediators including reactive oxygen species (ROS). Excess ROS results in oxidative stress, being a risk factor of age-associated diseases initiation and progression, including Alzheimer's disease (AD). Ions of aluminum are known as strong ROS production promoters. AlCl3 chronic exposure was shown to initiate molecular biological features of neurodegenerative processes only in old animals. However, the systemic effects of AlCl3 on various organs beyond the CNS are scarcely described.
The aim was to assess morphological changes in the liver, thymus and spleen in adult and old male Wistar rats due to chronic AlCl3 exposure.
Materials and methods. The study included 40 male Wistar rats of 4-6 and 22-24 months old. Adult and old rats of experimental groups (n=10 each) were given water with AlCl3 100 mg/kg/day for 60 days. Two groups of control animals (n=10 each) were given drinking water. The organs were obtained on the experiment 61st day. On histological sections of the thymus, the volume fractions of the cortex and medulla were determined using the point counting method by G.G. Avtandilov. The volume fractions of white and red pulp, lymphoid nodules, and PALM-zone, as well as functional zones of lymphoid nodules (germinal center, marginal zone) were assessed in the spleen. In the liver, the relative number of binuclear hepatocytes and non-epithelial cells per 1000 cells at x1000 was determined.
Results. In adult rats of the experimental group, an increase in the relative number of binuclear hepatocytes was observed compared to the age-matched control, while the relative number of non-epithelial cells was higher in AlCl3-treated old rats than in the old controls. A volumetric proportions decrease in the the spleen’s lymphoid nodules germinal centers was observed in both groups of old animals relative to adult ones.
Conclusion. AlCl3 at a dose of 100 mg/kg/day for 60 days in adult and old rats does not lead to pathological changes in the liver, thymus and spleen. The absence of toxic effects on these organs accompanying pronounced morphofunctional changes in the CNS, previously described in this model in old animals, proves the relevance of AlCl3 chronic exposure for in vivo modeling and further study of the mechanisms of age-related neurodegenerative processes’ initiation and progression.