Protein Catabolites As Blood-Based Biomarkers Of Aging Physiology: Findings From The Dog Aging Project

Analytical
A study using data from the Dog Aging Project identified specific protein breakdown products in the blood, called post-translationally modified amino acids, as reliable indicators of aging in dogs, with kidney function mediating about half of their age-related increase.
Author

Gemini

Published

November 5, 2025

Scientists are constantly searching for ways to understand and track aging, and our canine companions offer a unique opportunity to gain insights into this complex process. Dogs share many genetic and environmental factors with humans, making them excellent models for studying how we age.

In a recent investigation involving nearly 800 dogs, researchers looked closely at the “metabolome”—the complete set of small molecules found in the blood that are involved in metabolism. They discovered that a significant portion—about 36% to 40%—of these circulating molecules change predictably as dogs get older.

A key finding was the identification of a particular group of molecules called post-translationally modified amino acids (ptmAAs). These molecules are essentially byproducts created when proteins in the body break down. The study found that levels of these ptmAAs consistently increased with age, regardless of the dog’s breed, size, or sex.

Furthermore, the research highlighted a strong link between these ptmAA levels and kidney function. It appears that the kidneys play a crucial role in filtering these protein breakdown products from the blood, and a decline in kidney function contributes to their accumulation as an animal ages. This suggests that monitoring ptmAAs could provide valuable information about an individual’s biological age and the health of their kidneys, potentially offering new ways to track the aging process and understand healthy longevity in both dogs and humans.