Extracellular vesicle-associated Aβ mediates trans-neuronal bioenergetic and Ca2+-handling deficits in Alzheimer’s disease models
Open accessAbstract
Alzheimer’s disease (AD) is an age-related neurodegenerative disorder in which aggregation-prone neurotoxic amyloid β-peptide (Aβ) accumulates in the brain. Extracellular vesicles (EVs), including exosomes, are small 50–150 nm membrane vesicles that have recently been implicated in the prion-like spread of self-aggregating proteins. Here we report that EVs isolated from AD patient cerebrospinal fluid and plasma, from the plasma of two AD mouse models, and from the medium of neural cells expressing familial AD presenilin 1 mutations, destabilize neuronal Ca 2+homeostasis, impair mitochondrial function, and sensitize neurons to excitotoxicity. EVs contain a relatively low amount of Aβ but have an increased Aβ42/ Aβ40 ratio; the majority of Aβ is located on the surface of the EVs. Impairment of lysosome function results in increased generation of EVs with elevated Aβ42 levels. EVs may mediate transcellular spread of pathogenic Aβ species that impair neuronal Ca 2+handling and mitochondrial function, and may thereby render neurons vulnerable to excitotoxicity.
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Several studies have shown that both extracellular free Aβ and Aβ-contained EVs play a role in the progression of AD pathology.
“Several studies have shown that both extracellular free Aβ and Aβ-contained EVs play a role in the progression of AD pathology [136–140].”
From Extracellular vesicles as nanotheranostic platforms for targeted neurological disorder interventions (2024) · cites this paper as [138]
The Introduction reports that injecting Aβ from biological or synthetic sources into mouse brains accelerates Aβ aggregation. The Discussion finds that Aβ-associated EVs are neurotoxic in AD models, but describes their role in propagating AD pathology as possible and says whether EV-associated Aβ has a critical role in AD pathogenesis remains to be determined. Thus the paper does not establish that both forms contribute to disease progression. (LLM, conf=0.86)
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- Authors
- Eitan, E., Hutchison, E. R., Marosi, K., Comotto, J., Mustapic, M., Nigam, S. M., Suire, C., Maharana, C., Jicha, G. A., Liu, D., Machairaki, V., Witwer, K. W., Kapogiannis, D., & Mattson, M. P.
- Affiliations
- National Institutes of Health (US)
- University of Kentucky (US)
- Johns Hopkins University (US)
- Corresponding author
- Mattson, Mark P
- ORCID
- Venue
- npj Aging and Mechanisms of Disease
- Published
- 2016-09-22
- Volume
- 2
- Issue
- 1
- ISSN
- 2056-3973 (ISSN-L)
- PMC
- PMC5137253
- OpenAlex
- W2522545878
- Cited by
- 129
- References
- 9
- Citations by year
- 2026: 8 · 2025: 12 · 2024: 11 · 2023: 12 · 2022: 17 · 2021: 17 · 2020: 26 · 2019: 10 · 2018: 11 · 2017: 5
- FWCI
- 6.98
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Locations
- npj Aging and Mechanisms of Disease (publishedVersion, cc-by)
- Europe PMC (PubMed Central) (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- UKnowledge (University of Kentucky) (submittedVersion, cc-by)
- Funders
- University of Kentucky
- National Institutes of Health
- National Institute on Aging (P30AG028383, ZIAAG000312)
- Topics
- Health Sciences › Medicine › Physiology › Alzheimer's disease research and treatments
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Extracellular vesicles in disease
- Life Sciences › Neuroscience › Neurology › Neuroinflammation and Neurodegeneration Mechanisms
- Keywords
- Alzheimer's disease, extracellular vesicles, exosomes, amyloid-beta, Aβ42/Aβ40 ratio, calcium homeostasis, mitochondrial dysfunction, excitotoxicity, lysosomal dysfunction, presenilin 1 mutations, cerebrospinal fluid, plasma vesicles, neurodegeneration
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