Evidence of intraneuronal Aß accumulation preceding tau pathology in the entorhinal cortex.
Acta Neuropathol
; 136(6): 901-917, 2018 12.
Article
em En
| MEDLINE
| ID: mdl-30362029
ABSTRACT
Growing evidence gathered from transgenic animal models of Alzheimer's disease (AD) indicates that the intraneuronal accumulation of amyloid-ß (Aß) peptides is an early event in the AD pathogenesis, producing cognitive deficits before the deposition of insoluble plaques. Levels of soluble Aß are also a strong indicator of synaptic deficits and concurrent AD neuropathologies in post-mortem AD brain; however, it remains poorly understood how this soluble amyloid pool builds within the brain in the decades leading up to diagnosis, when a patient is likely most amenable to early therapeutic interventions. Indeed, characterizing early intracellular Aß accumulation in humans has been hampered by the lack of Aß-specific antibodies, variability in the quality of available human brain tissue and the limitations of conventional microscopy. We therefore sought to investigate the development of the intraneuronal Aß pathology using extremely high-quality post-mortem brain material obtained from a cohort of non-demented subjects with short post-mortem intervals and processed by perfusion-fixation. Using well-characterized monoclonal antibodies, we demonstrate that the age-dependent intraneuronal accumulation of soluble Aß is pervasive throughout the entorhinal cortex and hippocampus, and that this phase of the amyloid pathology becomes established within AD-vulnerable regions before the deposition of Aß plaques and the formation of tau neurofibrillary tangles. We also show for the first time in post-mortem human brain that Aß oligomers do in fact accumulate intraneuronally, before the formation of extracellular plaques. Finally, we validated the origin of the Aß-immunopositive pool by resolving Aß- and APP/CTF-immunoreactive sites using super resolution structured illumination microscopy. Together, these findings indicate that the lifelong accrual of intraneuronal Aß may be a potential trigger for downstream AD-related pathogenic events in early disease stages.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Peptídeos beta-Amiloides
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Proteínas tau
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Córtex Entorrinal
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Neurópilo
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Doença de Alzheimer
Tipo de estudo:
Prognostic_studies
Limite:
Aged
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Aged80
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Animals
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Ano de publicação:
2018
Tipo de documento:
Article