FIGURE 1.

Feed forward loop of insulin resistance and Alzheimer disease. Both insulin resistance and Alzheimer disease lead to activation of nuclear factor kappa B (NF-κB), increased cytokine secretion and increased reactive oxygen species (ROS) levels, triggering increased amyloid beta (amyloid β) and tau hyperphosphorylation. In addition, insulin resistance lowers levels of insulin degrading enzyme (IDE), resulting in impaired amyloid β phagocytosis. Higher levels of amyloid β, in turn, leads to decreased expression of the insulin receptor, which results in insulin resistance, creating a vicious cycle.