GLP-1R agonists (e.g., exendin-4 and liraglutide) reduce APP expression and processing in the brains of AD model mice through the activation of GLP-1R, decrease Aβ protein production and plaque aggregation, and thus improve their spatial memory capacity (McClean et al., 2015; Wang et al., 2016). Here, GLP1R is linked to Alzheimer disease.