GSK3B and Alzheimer disease: A further investigation revealed a troubling trend in people with both AD and T2DM: a significant decrease in the phosphorylation of markers related to insulin signaling (insulin receptor beta (IRβ), phosphatidylinositol 3,4,5-trisphosphate (PI3K), 3-phosphoinositide-dependent protein kinase 1 (PDK1), protein kinase B (AKT) and GSK-3β).