MAPT and Alzheimer disease: Vacuolar degeneration of muscle fibers in IBM is accompanied by multi-protein aggregates, such as β-amyloid (Aβ), phosphorylated tau (p-tau) in the form of paired helical filaments similar to degenerative hippocampal pyramidal cells in AD in regard to proteasome inhibition, endoplasmic reticulum stress, and lysosomal degradation [5], [6].