NfL: A Universal Biomarker for Nerve Damage and Aging Across Species

The protein Neurofilament Light Chain (NfL), an indicator of nerve damage, has been found to be detectable in the blood of numerous animals, with levels increasing alongside age. Experts from the German Center for Neurodegenerative Diseases (DZNE) and the Hertie Institute for Clinical Brain Research (HIH) at the University of Tübingen published these findings in the scientific journal "PLOS Biology".

They propose that this biomarker could aid in assessing the biological age of animals and estimating their life expectancy. NfL is released into the bloodstream when neurons undergo change or degenerate, whether due to disease or normal aging.

"This biomarker could aid in assessing the biological age of animals and estimating their life expectancy."

NfL as a Predictive Marker

Elevated NfL levels are observed in human neurodegenerative diseases like Alzheimer's and ALS, and also rise in healthy individuals with age. A similar age-related increase has been documented in mice, cats, dogs, and horses.

Studies in humans indicate that higher NfL concentrations in the blood of elderly individuals are associated with an increased risk of death, suggesting a connection between neurological aging and mortality.

Research in mice has yielded similar results; monitoring 44 older animals over four months showed that those with slower rising NfL levels lived comparatively longer, while faster increases correlated with shorter lifespans.

Broad Species Examination

In addition to the detailed studies on mice, cats, dogs, and horses, a further 53 animal species were examined on a sampling basis. This collaboration included the zoo in Stuttgart, Germany, the Vetsuisse Faculty at the University of Zurich, and a veterinary diagnostics laboratory.

NfL protein was detected in the blood of all mammals tested.

However, it was only found in some reptiles and birds, such as a crocodile and a parrot. A possible explanation for the limited detection in these species is that the NfL protein sequence might differ slightly from its human counterpart, affecting the assay's ability to detect it.

The overall data suggests that analysis methods originating from dementia research hold promise for veterinary medicine in evaluating the biological age, neurological health, and life expectancy of animals.