Rethinking Diabetes from the Perspective of Diverse Insulin Actions in Various Organs.

Diabetes mellitus is defined as a group of metabolic diseases characterized by chronic hyperglycemia based on insufficient insulin action. At present, treatment for diabetes aims to prevent micro- and macrovascular complications. Although advances have been made in methods of controlling the risk factors of complications, including blood glucose management, there is still no effective treatment to cure diabetes. This is largely because we do not fully understand what diabetes is. To cure diabetes, it is necessary to elucidate the whole picture of insulin actions including those other than metabolic actions in various tissues and to understand what disorders are caused by its reduction or excess. This article reviews diverse insulin actions in various organs and the effects of their deficiency on diabetes, its complications, and associated diseases.