Aging processes and the development of age-related diseases mainly occur at the cellular level. In order to gain a deeper understanding of these processes and thereby open up opportunities for diagnosis and prevention, it is necessary to analyze tissue-specific alterations that are obtained in the context of long-term feeding experiments using animal models of age- and diet-related diseases. The aim is to characterize tissue-specific oxPTM patterns as well as their variability during the aging process and based on gender and diet as well as the development of age-related diseases.
For this purpose, rat strains with an increased tendency to develop cardiovascular diseases (e.g. Spontaneously Hypertensive Heart Failure rats) or disorders of glucose and insulin metabolism (e.g. Zucker Diabetic Fatty rats) are used next to Wistar rats representing the "wildtype". The animals are kept in small groups for a maximum period of 21 months and the health status will be characterized by the regular measurement of body weight, blood pressure, glucose tolerance, activity and food intake. In addition to a standard diet, the influence of a so-called Western Diet (increased content of saturated fatty acids and mono- and disaccharides), which is associated with the pathogenesis and pathophysiology of diet-related diseases in both humans and laboratory rodents, is taken into account. Blood and tissue samples are obtained at defined time points, with a focus on the organs that are either of central importance for the metabolism (liver) or frequently affected by changes in the aging process and are subject to age-related diseases (heart, kidneys and pancreas).
In order to fully characterize the aging phenotype of the animals, analysis of general clinical parameters (e.g. cholesterol, triglycerides, glucose, insulin, creatinine, C-reactive protein), parameters of the oxidative status (including protein carbonylation, antioxidant capacity), and a general histopathological evaluation will be performed next to the analysis of oxPTM.