AβInternalization by Neurons and Glia

Abstract

In the brain, the amyloidβpeptide (Aβ) exists extracellularly and inside neurons. The intracellular accumulation of Aβin Alzheimer's disease brain has been questioned for a long time. However, there is now sufficient strong evidence indicating that accumulation of Aβinside neurons plays an important role in the pathogenesis of Alzheimer's disease. Intraneuronal Aβoriginates from intracellular cleavage of APP and from Aβinternalization from the extracellular milieu. We discuss here the different molecular mechanisms that are responsible for Aβinternalization in neurons and the links between Aβinternalization and neuronal dysfunction and death. A brief description of Aβuptake by glia is also presented.