MAPT and Alzheimer disease: Senile plaques (SP) formed by extracellular amyloid-β (Aβ) peptide deposition and neurofibrillary tangles (NFTs) formed by excessive phosphorylation of intracellular tau protein constitute the hallmarks of AD [6, 7], which is also accompanied by the massive loss of neurons and synapses, as well as brain structural and functional abnormalities [8–10].