Features of blood aging in Macaca fascicularis

The study of hematopoietic system aging in non-anthropoid primates such as the Сynomolgus macaque (Macaca fascicularis) provides a unique opportunity to understand the evolutionarily conserved mechanisms of human aging and the age-related dynamics of the main cellular and biochemical parameters of peripheral blood. These data are helpful for evaluating the results of preclinical studies on animals of different age groups. Aging of immune system is accompanied by impaired cellular function and changed ratios of cell populations in circulating blood. Despite similarity of quantitative indices, the age-related dynamics of blood cells are different in humans and Сynomolgus macaque. The aim of the study was to conduct a comparative analysis of age-related changes in cellular composition of blood and biochemical parameters of blood in Cynomolgus macaques and human donors. This study included groups of animals aged 4-9 years, as well as a unique group of old individuals aged 18-27 years. In addition, we analyzed blood samples obtained from volunteer donors of different age groups (20-30, 31-56 and 57-85 years). Absolute blood cell counts in donors and macaques were assessed, biochemical blood analysis was performed in macaques of different age groups, and a comparative analysis of blood aging in humans and macaques was conducted. In this study, macaques showed a decrease in platelet counts with age, indicating a decreased production of megakaryocytes and their precursors in bone marrow. Aging in Сynomolgus macaques was also accompanied by a significant increase in triglyceride and globulin levels in the blood, as well as a trend toward a decrease in albumin levels, thus reducing the total albumin/globulin ratio. This index in human donors is associated with overall health, and its decrease is observed with age. In males and females, there is also a trend toward an increase in glucose, bilirubin, cholesterol, and inflammatory enzymes with age. Creatinine levels were significantly higher in males regardless of age and exceeded this indicator in females.