APP and Alzheimer disease: Various GLP-1R or GLP-1R/GIPR dual agonists prevented presynaptic synaptophysin and postsynaptic density protein 95 (PSD-95)/drebrin loss in the brains of mice injected with Aβ oligomers (Batista et al., 2018) as well as multiple hippocampal and cortical regions of APP/presenilin-1 (PS1) (McClean et al., 2011, 2015; Lourenco et al., 2013; McClean and Holscher, 2014a,b; Panagaki et al., 2018), 3 × Tg (APPswe, TauP301L, and PS1M146V) (Cai et al., 2021; Zheng et al., 2021) or 5xFAD (APPswe, APPI716V, APPV717I, PS11M146L/1L286V) (An et al., 2019; Park et al., 2021) AD rodents.