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Updated: Jul 30, 2026
08:16
Stereotaxic Infusion of Oligomeric Amyloid-beta into the Mouse Hippocampus
Published on: June 17, 2015
Astrocytes down-regulate neuronal beta-amyloid precursor protein expression and modify its processing in an
1Laboratory of Biochemical Genetics and Metabolism, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA. vincentb@ipmc.cnrs.fr
The European Journal of Neuroscience
|September 13, 2001
Summary
Astrocytes regulate amyloid precursor protein (APP) expression in neurons. Apolipoprotein E4 (apoE4) from astrocytes promotes Alzheimer's disease amyloidogenesis, while apoE2 offers protection.
Area of Science:
- Neuroscience
- Molecular Biology
- Genetics
Background:
- Alzheimer's disease (AD) is a prevalent neurodegenerative disorder in aging populations.
- AD pathogenesis involves amyloid beta (A beta) protein deposition, a fragment of beta-amyloid precursor protein (APP).
- Apolipoprotein E (apoE) polymorphism, particularly apoE4, is a significant risk factor for AD.
Purpose of the Study:
- To investigate the relationship between apolipoprotein E (apoE) and amyloidogenesis in the central nervous system (CNS).
- To assess how astrocyte-derived apoE influences neuronal APP processing and A beta production.
Main Methods:
- Primary cortical neurons overexpressing humanized APP695 with the Swedish mutation (hAPP(695sw)) were used.
- Neurons were co-cultured with astrocytes from wild-type, apoE-deficient, or apoE-humanized mice (apoE2, E3, E4).
- APP expression and processing were analyzed following co-culture, conditioned media treatment, or exposure to recombinant/purified apoE.
Main Results:
- Neuronal APP expression decreased significantly only when co-cultured with astrocytes, indicating a requirement for cell-cell contact.
- Astrocytes secreting apoE4, but not recombinant apoE4, increased A beta production and decreased soluble APP alpha (sAPP alpha) secretion in direct neuronal contact.
- Astrocytes secreting apoE2 demonstrated a protective effect, reducing amyloidogenic pathway markers.
Conclusions:
- Astrocytes play a crucial role in regulating neuronal APP expression.
- Astrocyte-derived apoE4 promotes the amyloidogenic pathway in an apoE4-dependent manner, contributing to Alzheimer's disease pathogenesis.
- ApoE and astrocytic factors interact to modulate Alzheimer's disease pathology.
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