APP and amyloidosis: Interestingly, APP/PS1 mice, a mouse model of amyloidosis that expresses mutated amyloid-β protein precursor (APP) (Swedish mutation, K595N/M596L) and mutated presenilin (PS1) (deltaE9 PS1 exon deletion) [13], were more susceptible to HFD-induced weight gain [14,15,16] accompanied by increased AT mass and leptin levels [16].