1. The present review focuses on the effects of varying levels of GLUT-4, the insulin-sensitive glucose transporter, on insulin sensitivity and whole body glucose homeostasis. 2. Three mouse models are discussed including myosin light chain (MLC)-GLUT-4 mice which overexpress GLUT-4 specifically in skeletal muscle, GLUT-4 null mice which express no GLUT-4 and the MLC-GLUT-4 null mice which express GLUT-4 only in skeletal muscle. Overexpressing GLUT-4 specifically in the skeletal muscle results in increased insulin sensitivity in the MLC-GLUT-4 mice. In contrast, the GLUT-4 null mice exhibit insulin intolerance accompanied by abnormalities in glucose and lipid metabolism. Restoring GLUT-4 expression in skeletal muscle in the MLC-GLUT-4 null mice results in normal glucose metabolism but continued abnormal lipid metabolism. 3. The results of experiments using these mouse models demonstrates that modifying the expression of GLUT-4 profoundly affects whole body insulin action and consequently glucose and lipid metabolism.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.