Figure 1.Neuropathological hallmarks that characterize Alzheimer’s disease. As Alzheimer's disease progresses, the brain tissue shrinks, the volume of the ventricle, which contains cerebrospinal fluid, increases markedly. At the molecular level: 1. Amyloid-β peptides are produced by the cleavage of the amyloid precursor protein (APP) in the membrane of the neurons. 2. In the space between the neurons, amyloid-β forms oligomers that are thought to disrupt the function of the synapses and act in receptors present in the neuron plasma membrane. 3. The fibrils of the amyloid-β oligomers are added in plaques, which interfere with the function of the neurons. 4. Tau hyperphosphorylation causes neurofibrillary tangles within neurons, displacing intracellular organelles and disrupting vesicular transport.
