Alzheimer disease (AD) is a progressive neurodegenerative disorder characterized by the accumulation of amyloid plaques and tangles and the loss of neurons in the brain. Many risk factors lead to the development of AD. The disruption of more than one protein activity may be responsible for the late-onset form of AD. Plaques are composed of aggregated fibrils of beta-amyloid (fAbeta) and are surrounded by microglia, the immune response cells of the central nervous system (CNS). Microglia internalize fAbeta and deliver it to their lysosomes, but do not completely degrade it. The lysosomal pH of microglia is higher than that of macrophage cells, and this may decrease the lysosomal enzyme activity. Microglia treated with macrophage colony-stimulating factor (MCSF) have a lower lysosomal pH and degrade fAbeta more efficiently than untreated microglia.
展开▼
