Ergothioneine (14) was tested in the 5XFAD AD transgenic mouse model, characterized for overexpressing five of the known familial AD mutations related to presenilins 1 and 2 that lead to an increased Aβ deposition, higher plasma, and brain levels of Aβ40 and Aβ42, along with elevated pro-inflammatory cytokine levels [67]. This evidence concerns the gene PSEN1 and Alzheimer disease.