Genotypic effects of APOE-ε4 on resting-state connectivity in cognitively intact individuals support functional brain compensation

The investigation of resting-state functional connectivity (rsFC) in asymptomatic individuals at genetic risk for Alzheimer's disease (AD) enables discovering the earliest brain alterations in preclinical stages of the disease. The APOE-ε4 variant is the major genetic risk factor for AD, an...

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Detalles Bibliográficos
Autores: Cacciaglia, Raffaele, Operto, Grégory, Falcón, Carles, González de Echávarri, José Maria, Sánchez Benavides, Gonzalo, Brugulat Serrat, Anna, 1986-, Milà Alomà, Marta, Blennow, Kaj, Zetterberg, Henrik, Molinuevo, José Luis, Suárez-Calvet, Marc, Gispert, Juan Domingo, ALFA Study
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2022
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:10230/54413
Acceso en línea:http://hdl.handle.net/10230/54413
http://dx.doi.org/10.1093/cercor/bhac239
Access Level:acceso abierto
Palabra clave:APOE-ε4
Alzheimer’s disease
Compensation
Resting-state connectivity
Descripción
Sumario:The investigation of resting-state functional connectivity (rsFC) in asymptomatic individuals at genetic risk for Alzheimer's disease (AD) enables discovering the earliest brain alterations in preclinical stages of the disease. The APOE-ε4 variant is the major genetic risk factor for AD, and previous studies have reported rsFC abnormalities in carriers of the ε4 allele. Yet, no study has assessed APOE-ε4 gene-dose effects on rsFC measures, and only a few studies included measures of cognitive performance to aid a clinical interpretation. We assessed the impact of APOE-ε4 on rsFC in a sample of 429 cognitively unimpaired individuals hosting a high number of ε4 homozygotes (n = 58), which enabled testing different models of genetic penetrance. We used independent component analysis and found a reduced rsFC as a function of the APOE-ε4 allelic load in the temporal default-mode and the medial temporal networks, while recessive effects were found in the extrastriate and limbic networks. Some of these results were replicated in a subsample with negative amyloid markers. Interaction with cognitive data suggests that such a network reorganization may support cognitive performance in the ε4-homozygotes. Our data indicate that APOE-ε4 shapes the functional architecture of the resting brain and favor the idea of a network-based functional compensation.