Specifically, the SSRI escitalopram was found to reduce Aβ1-42 induced hyperphosphorylation of tau via the 5-HT1AR mediated Akt/GSK-3β pathway in the hippocampal neurons (Wang et al., 2016) (Fig. 1) and this could be a key pathway for the potential treatment of AD, especially in its early stage. This evidence concerns the gene MAPT and Alzheimer disease.