GLUT4 Goes Abnormal: Disregulation of the Insulin-Responsive Glucose Transporter in Abnormal Metabolic States

The overall objective of this paper is to review the mechanisms by which various metabolic and cellular signals, as well as nuclear transcription factors, regulate the expression and function of the insulin responsive glucose transporter-4 (GLUT4) gene. Reviewing this information will help the reader to understand the molecular processes involved in both glucose homeostasis and the pathogenesis of abnormal metabolic states involving impaired insulin action, such as insulin resistance and diabetes mellitus type 2 (DM2). The same molecular mechanisms are also involved in tumorigenesis. Studies on GLUT4 regulation, its translocation machinery, and intrinsic activity have contributed valuable knowledge that may be useful for developing therapeutic strategies aimed at increasing GLUT4 protein levels, which could potentially improve glucose homeostasis in insulin resistance and diabetes.