Figure 4.

Processes that are directly or indirectly affected by amyloid fiber formation and contribute to neurodegeneration. Toxic oligomers and protofibrils, which form on the pathway from soluble amyloid monomers to insoluble fibers, have been shown to accumulate in the extracellular space, such as synapses in which they influence cell–cell communication or in cells in which they alter energy metabolism, cause mitochondrial dysfunction, and trigger apoptosis. Polyphosphate (polyP) has been shown to play critical roles in all of these processes.