APP and Alzheimer disease: In this study, we used the APP/PS1 transgenic mouse model as it has been used previously to evaluate the process of amyloidogenesis at the pre-dementia phase of AD through the accumulation of Aβ deposits and plaques in the Tg mouse brain tissues and the retina (Ning et al., 2008; Zahs and Ashe, 2010; Shah et al., 2017).