Using label-free Raman spectroscopy to quantify matrix-associated aging products in tissues of various organs in an animal model

The objective of the study was to conduct a comparative assessment of old and young tissues, measuring shifts in substances associated with aging in the animal model. The measurements were performed by label-free Raman spectroscopy using cryosections of tissues from old and young organs (brain, lungs, and kidneys) of Djungarian hamsters. The study identified characteristic changes in the main components of matrix-associated aging products. In the tissue of young and old lungs, there was a significant increase in the intensity from young to old lung tissue of most peaks of pentosidine (1480, 1064, 1048, 840 cm–1) and carboxymethyllysine (926, 852 cm–1). In the brain, an increase in intensity from young to old brain tissue was observed for carboxymethyllysine at 1460 cm–1 and for type I collagen at 1319, 1213, 1003, and 854 cm–1. In the kidneys, an increase in intensity from young to old kidney tissue was observed for carboxymethyllysine at 1156 cm–1 and for type I collagen at 1453 cm–1. The results support using this animal model to test mechanisms of heterogeneity in aging across various organs, as well as using these peak values to assess the functional state of matrix-associated markers and the extracellular matrix overall.