Affiliation:
1. Experimental Dementia Research Unit, Department of Experimental Medical Science, Lund University
2. Medical Microspectroscopy, Department of Experimental Medical Science, Lund University
3. iNOVA4Health, NOVA Medical School | Faculdade de Ciências Médicas, Universidade Nova de Lisboa
Abstract
Apolipoprotein E4 (ApoE4) is the most important genetic risk factor for Alzheimer’s disease (AD). Among the earliest changes in AD is endosomal enlargement in neurons, which was reported as enhanced in ApoE4 carriers. ApoE is thought to be internalized into endosomes of neurons, whereas β-amyloid (Aβ) accumulates within neuronal endosomes early in AD. However, it remains unknown whether ApoE and Aβ intersect intracellularly. We show that internalized astrocytic ApoE localizes mostly to lysosomes in neuroblastoma cells and astrocytes, whereas in neurons, it preferentially localizes to endosomes–autophagosomes of neurites. In AD transgenic neurons, astrocyte-derived ApoE intersects intracellularly with amyloid precursor protein/Aβ. Moreover, ApoE4 increases the levels of endogenous and internalized Aβ42in neurons. Taken together, we demonstrate differential localization of ApoE in neurons, astrocytes, and neuron-like cells, and show that internalized ApoE intersects with amyloid precursor protein/Aβ in neurons, which may be of considerable relevance to AD.
Funder
Vetenskapsrådet
EC | Horizon Europe | Excellent Science | HORIZON EUROPE Marie Sklodowska-Curie Actions
Publisher
Life Science Alliance, LLC
Subject
Health, Toxicology and Mutagenesis,Plant Science,Biochemistry, Genetics and Molecular Biology (miscellaneous),Ecology