Advances in biomarker discovery for canine cognitive dysfunction: a comprehensive structured narrative review and...

Area of Science:

• Neuroscience
• Veterinary Medicine
• Biomarker Discovery

Background:

• Canine Cognitive Dysfunction (CCD) mirrors human Alzheimer's disease (AD) in dogs.
• Objective diagnostic tools and biomarkers are crucial for CCD staging and treatment monitoring.

Purpose of the Study:

• To review cerebrospinal fluid (CSF) and blood-based biomarkers (BBM) for Canine Cognitive Dysfunction.
• To evaluate biomarkers including amyloid-β (Aβ), neurofilament light chain (NfL), tau, and glial fibrillary acidic protein (GFAP).

Main Methods:

• Systematic review of existing scientific literature on CCD biomarkers.
• Analysis of studies focusing on Aβ, NfL, tau, and GFAP in CSF and blood samples.

Main Results:

• Aβ alterations in CCD resemble early AD phases.
• Tau pathology in CCD is primarily synaptic, limiting diagnostic use.
• Neurofilament light chain (NfL) is a robust biomarker, increasing with age and cognitive decline.
• GFAP shows inconsistent associations and remains exploratory.

Conclusions:

• NfL is the leading biomarker candidate for staging and monitoring CCD progression.
• A multimodal approach integrating Aβ, axonal injury (NfL), and glial activation (GFAP) is recommended.
• Standardized criteria and longitudinal studies are needed to enhance CCD's translational value as an AD model.