MAPT and Alzheimer disease: There are many hypotheses about the mechanisms of AD, including synaptic dysfunctions hypothesis, cholinergic theory, amyloid cascade hypothesis, tau cascade hypothesis, neuroinflammation, and gut-brain axis hypotheses (Craig et al., 2011; Calsolaro and Edison, 2016; Kowalski and Mulak, 2019; Ju and Tam, 2022).