MAPT and Alzheimer disease: Many recent clinical trials and experiments have proposed several hypotheses, including neuroinflammation (Cibelli et al., 2010; Safavynia and Goldstein, 2018; Xiang et al., 2019), synapse dysfunction (Xu et al., 2017), amyloid beta (Aβ) accumulation, and tau protein phosphorylation (Yu et al., 2020), which indicate that a common pathogenic pathway exists between PNDs and neurodegenerative disorders, especially AD.