Abstract
The aged canine is a higher animal model that naturally accumulates β-amyloid (Aβ) and shows age-related cognitive decline. However, profiles of Aβ accumulation in different species (40 vs. 42), its assembly states, and Aβ precursor protein (APP) processing as a function of age remain unexplored. In this study, we show that Aβ increases progressively with age as detected in extracellular plaques and biochemically extractable Aβ40 and Aβ42 species. Soluble oligomeric forms of the peptide, with specific increases in an Aβ oligomer migrating at 56 kDa, also increase with age. Changes in APP processing could potentially explain why Aβ accumulates, and we show age-related shifts toward decreased total APP protein and nonamyloidogenic (α-secretase) processing coupled with increased amyloidogenic (β-secretase) cleavage of APP. Importantly, we describe Aβ pathology in the cingulate and temporal cortex and provide a description of oligomeric Aβ across the canine lifespan. Our findings are in line with observations in the human brain, suggesting that canines are a valuable higher animal model for the study of Aβ pathogenesis.
Original language | English |
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Pages (from-to) | 108-120 |
Number of pages | 13 |
Journal | Neurobiology of Aging |
Volume | 33 |
Issue number | 1 |
DOIs | |
State | Published - Jan 2012 |
Bibliographical note
Funding Information:The authors thank the following people for technical assistance and advice: Jennifer Thompson for brain oligomer extractions, Anna Pensalfini for dot blots, Paul Adlard and Wayne Poon for the enzyme activity assays, and Xiaohong Wang for BACE1 Western blots. Funding was provided by NIH grants NS058383 and AG005119 (to MPM), AG12694 , AG17066 (to CWC) and AG032550 (to EH).
Keywords
- ADAM10
- APP
- Abeta star 56 kDa
- Beta amyloid
- C-terminal fragments of APP
- Canine
- Cingulate
- Dog
- Insulin degrading enzyme
- Neprilysin
- Oligomer
- Secretase
- Temporal
ASJC Scopus subject areas
- General Neuroscience
- Aging
- Clinical Neurology
- Developmental Biology
- Geriatrics and Gerontology