GDF15 and Alzheimer disease: We focused on gene expression changes in insulin receptor-mediated signalling Ir, Igfr1, Irs2, and Igf [24], related neurotrophic factors Bdnf and Syp, and mitochondrial regulator Pgc-1α [35], as well as markers of ageing associated with AD, Egr1, Gdf15, Sitr1, Sqstm, Arc, and Cldn5 [36,37,38,39,40,41] in the prefrontal cortex of APPswe/PS1dE9 mice.