Plasma Concentrations of the Amyloid-β Peptides in Young Volunteers: The Influence of the APOE Genotype

Article type: Research Article

Authors: Zimmermann, Ruediger^a | Huber, Ellen^a | Schamber, Christine^a | Lelental, Natalia^a | Mroczko, Barbara^b | Brandner, Sebastian^c | Maler, Juan Manuel^a | Oberstein, Timo^a | Szmitkowski, Maciej^d | Rauh, Manfred^e | Kornhuber, Johannes^a | Lewczuk, Piotr^{a; *}

Affiliations: [a] Department of Psychiatry and Psychotherapy, Universitätsklinikum Erlangen, and Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany | [b] Department of Neurodegeneration Diagnostics, Medical University of Białystok, and Department of Biochemical Diagnostics, University Hospital in Białystok, Białystok, Poland | [c] Department of Neurosurgery, Universitätsklinikum Erlangen, and Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany | [d] Department of Biochemical Diagnostics, Medical University of Białystok, Białystok, Poland | [e] Department of Paediatrics, Universitätsklinikum Erlangen, and Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany

Correspondence: [*] Correspondence to: Prof. Dr. med. Piotr Lewczuk, Lab for Clinical Neurochemistry and Neurochemical Dementia Diagnostics, Department of Psychiatry and Psychotherapy, Schwabachanlage 6, 91054 Erlangen, Germany. Tel.: +49 9131 85 34324; Fax: +49 9131 34 238; E-mail: [email protected].

Abstract: Changes in the concentrations of amyloid-β (Aβ) in the body fluids are the earliest alterations observed in Alzheimer's disease (AD), however, there is a lack of data about how early these alterations occur, before the onset of the clinical symptoms. APOE genotype is the most recognized genetic risk/protective factor of AD, meaning that a group of non-demented persons carrying ε4 allele is enriched in the subjects who will develop AD, compared to the group of non-carriers. Therefore, we studied the plasma concentrations of Aβ peptides (Aβ1-42, Aβ1-40, Aβx-42, and Aβx-40), and the APOE genotype in 173 young volunteers (average age, 28 ± 7.6 years) without memory deficits, in order to see whether the non-demented group of subjects at risk already characterize with Aβ changes three-to-four decades before the age at which dementia usually occurs. We did not find statistically significant differences among the groups of ε4 carriers, ε3 homozygotes, and ε2 carriers. We conclude that the APOE genotype does not influence the metabolism of the Aβ peptides in young persons without memory deficits.

Keywords: Amyloid-β, APOE genotype, blood biomarkers, non-demented volunteers

DOI: 10.3233/JAD-132687

Journal: Journal of Alzheimer's Disease, vol. 40, no. 4, pp. 1055-1060, 2014