MAPT and Alzheimer disease: Synaptic alterations are actually a critical part of neurodegeneration that are strongly correlated with the morphological lesions of AD, neurotoxicities of tau and Aβ, and cognitive impairment, which induce various neurotoxic effects such as increased inflammation, increased oxidative pressure, and subsequently damages the nerve synapses of the brain (Jack et al., 2019; Srivastava et al., 2019; Knopman et al., 2021).