The Effect of Type 2 Diabetes Mellitus on the Development of Alzheimer's Disease and Its Molecular Mechanism

Abstract

Following increased epidemiological studies indicating the relationship between diabetes and Alzheimer-s disease (AD), Type 2 diabetes has been reported to be a risk factor for the progress of AD pathology. Insulin resistance that develops in the brain, impairment in the insulin signal delivery system and glucose metabolism have been shown among the most likely pathophysiological causes of AD. It has been reported that the increase in AD markers such as phospho tau and A beta in the type 2 diabetes model of rats is associated with the decrease in the insulin receptor (IR) signaling and insulin-like growth factor-1 receptors (IGF-1R) ratio. Furthermore, intracellular components such as phospho-AKT (protein kinase B) and phospho-glycogen synthase kinase-3 beta (GSK3 beta), which are members of IR pathway, have been proved to be reduced in AD. Due to the common molecular mechanisms underlying the pathological development of Type 2 Diabetes and AD, treatment protocols indicated in diabetes have been used in the treatment of AD.