This study utilized the APP/PS1-ob/ob animal model with both AD and T2DM and clearly demonstrated that the diabetic condition can aggravate cognitive impairment, Aβ deposition, tau phosphorylation, synaptic loss, neuronal death and inflammation in AD mice, and damage to calcium homeostasis may promote the progress of these pathophysiological processes. This evidence concerns the gene MAPT and Cognitive impairment.