Fig. 3

This figure summarizes the pathological cascades, and their relation with each other, occurring during the development of Alzheimer’s disease in white matter and cortex. While ischemia, excitotoxicity, oxidative stress, and iron overload in white matter damage oligodendrocytes, on one hand, and amyloid toxicity affects them, on the other hand, the iron released from damaged oligodendrocytes promotes amyloid polymerization and deposition in grey matter. The consequent demyelination and axonal loss result in further white matter damage and neuronal dysfunction. Neuronal dysfunction is also a result of amyloid deposition in cortex and a proposed cause for white matter abnormalities in AD patients. White matter hyperintensities are labelled with red in the MRI (FLAIR) scan of an AD patient. Blue arrows: direction of the damages originating in grey matter. Maroon arrows: direction of the damages originating in white matter. LV lateral ventricle