Challenges in Experimental Gerontology: Are Solutions Possible? On the Calculation of Xenobiotic Doses

The assessment of resistance to toxic compounds, the capacity of biological systems to adapt to diverse external factors, and the specific effects of pharmaceutical agents on animals of different ages constitute a crucial area of research in experimental gerontology. The present essay aims to analyse endogenous age-dependent structural and functional characteristics of the liver and kidneys, which influence the metabolism of xenobiotics, as well as potential methodological errors that may arise in addressing this critical issue. The study presents evidence indicating pronounced age-related changes in the relative mass and structural-functional properties of the liver and kidneys, which, in turn, affect the organism's response to xenobiotic exposure in both young and old animals. Failure to account for these age-dependent characteristics in experimental designs inevitably leads to erroneous conclusions. To address these fundamental issues in aging biology, the authors propose a research algorithm consisting of four key steps. Implementing this algorithm in experimental studies could facilitate at least partial standardization of research subjects, enable the identification of baseline functional states in individual organisms through preliminary longitudinal assessments, and allow for precise calculation of xenobiotic dosages by considering the structural-functional and age-related conditions of the liver and kidneys. The authors suggest that such an approach may help reduce the likelihood of erroneous findings in experimental gerontology.