Dogs reveal new blood biomarkers of aging: insights from the dog aging project

This video summarizes the paper “Protein Catabolites as Blood-Based Biomarkers of Aging Physiology: Findings from the Dog Aging Project” by Benjamin R. Harrison et al. (Aging Cell, 2025). Using blood samples from 784 companion dogs across the United States, the researchers performed large-scale plasma metabolomics to uncover how age alters metabolism in real-world genetic and environmental contexts. They found that about 36% of metabolites changed with age, with strong effects in acylcarnitines and post-translationally modified amino acids (ptmAAs), which are molecular by-products of protein breakdown. These ptmAAs increased consistently with age and were tightly linked to clinical markers of kidney function, such as creatinine and blood urea nitrogen, suggesting that slower clearance of protein catabolites contributes to age-related shifts in the blood metabolome. By integrating metabolomics with genomic and clinical data, the Dog Aging Project establishes ptmAAs as robust, diet-independent biomarkers of biological aging in dogs — and potentially in humans. This study highlights how our canine companions can accelerate discoveries in geroscience, bridging laboratory insights and natural aging in complex, diverse populations.