ATF4 and Alzheimer disease: In summary, quercetin exerts neuroprotective effects against chronic AD by targeting SIRT1 to regulate cellular senescence and aging-related multiple cellular processes, including SIRT1/Keap1/Nrf2/HO-1 and PI3K/Akt/GSK-3β mediated oxidative stress, SIRT1/NF-κB mediated inflammatory response, SIRT1/PGC1α/eIF2α/ATF4/CHOP mediated mitochondrial damage, and SIRT1/FoxO mediated autophagy (Figure 2 and Table 1).