INS and Alzheimer disease: Increased activation of Glycogen synthase kinase 3 beta (GSK3b) in the brains of AD patients, in particular the hippocampus, accompanies impaired insulin signaling downstream the insulin receptor/insulin-like growth factor receptor through the Phosphoinositide-3-kinase (PI3K)/AKT pathway, resulting in increased phosphorylation of tau and increased production of amyloid beta peptides [747,748,749,750,751,752].