Cortical amyloid-beta burden is associated with changes in intracortical myelin in cognitively normal older adults.
Transl Psychiatry
; 13(1): 115, 2023 04 06.
Article
em En
| MEDLINE
| ID: mdl-37024484
ABSTRACT
Amyloid-beta (Aß) aggregates and myelin breakdown are among the earliest detrimental effects of Alzheimer's disease (AD), likely inducing abnormal patterns of neuronal communication within cortical networks. However, human in vivo evidence linking Aß burden, intracortical myelin, and cortical synchronization is lacking in cognitively normal older individuals. Here, we addressed this question combining 18F-Florbetaben-PET imaging, cortical T1-weigthed/T2-weighted (T1w/T2w) ratio maps, and resting-state functional connectivity (rs-FC) in cognitively unimpaired older adults. Results showed that global Aß burden was both positively and negatively associated with the T1w/T2w ratio in different cortical territories. Affected cortical regions were further associated with abnormal patterns of rs-FC and with subclinical cognitive deficits. Finally, causal mediation analysis revealed that the negative impact of T1w/T2w ratio in left posterior cingulate cortex on processing speed was driven by Aß burden. Collectively, these findings provide novel insights into the relationship between initial Aß plaques and intracortical myelin before the onset of cognitive decline, which may contribute to monitor the efficacy of novel disease-modifying strategies in normal elderly individuals at risk for cognitive impairment.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Doença de Alzheimer
/
Disfunção Cognitiva
Tipo de estudo:
Risk_factors_studies
Limite:
Aged
/
Humans
Idioma:
En
Revista:
Transl Psychiatry
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Espanha