Supplementation with NAD+ precursors in animal models of AD can inhibit Aβ and tauopathies, increase the activity of PI3K-AKT and MAPK/ERK1/2 via NAD+-dependent SIRT1 and SIRT3, and eventually reverse cognitive impairment in 3 × Tg and APP/PS1 models (Hosseini et al., 2021; Wang et al., 2021). The gene discussed is APP; the disease is Alzheimer disease.