The 2019 review by Yoko M. Ambrosini and colleagues, published in Frontiers in Aging Neuroscience, examines how dogs provide an effective comparative model for studying the gut-brain axis (GBA) in the context of neurodegenerative diseases such as Alzheimer’s (AD) and Parkinson’s disease (PD). Aging dogs naturally experience cognitive decline, including memory and learning impairments, mimicking human patterns of neurodegeneration.
Like humans, dogs develop neuropathological changes such as β-amyloid (Aβ) accumulation in brain regions including the prefrontal cortex and hippocampus. They also exhibit tau pathology—a hallmark of dementia—in hippocampal synapses. This human-like progression positions canines as more reliable models than rodents for certain neurodegenerative research.
Importantly, the review emphasizes the early involvement of the gastrointestinal (GI) tract in neurodegenerative disease. Histopathological changes in the gut, along with alterations in the gut microbiome, often precede central nervous system symptoms by decades. Such findings underscore the GBA’s central role in disease progression.
Remarkably, the canine gut microbiome shares greater structural and functional similarity with that of humans compared to traditional rodent models. This similarity increases the translational potential of findings derived from dog studies, particularly regarding inflammation-driven brain disorders.
The authors also review current in vitro and in vivo models and argue that while limitations exist, dogs offer an unmatched bridge between mechanistic understanding and human clinical relevance. The review encourages further research into how canine GBA models can illuminate early disease biomarkers and inform therapeutic interventions.
Source: Yoko M. Ambrosini, D. C. Borcherding, A. Kanthasamy, H. J. Kim, A. Willette, A. Jergens, K. Allenspach, and J. Mochel. “The Gut-Brain Axis in Neurodegenerative Diseases and Relevance of the Canine Model: A Review.” Frontiers in Aging Neuroscience, Volume 11, Published 2019-06-18.
