January - March 2011, Volume 7, Issue 1

Ionescu-Tirgoviste C

Insulin Resistance - What is Myth and What is Reality?

Acta Endo (Buc) 2011, 7 (1): 123-146
doi: 10.4183/aeb.2011.123

Diabetes mellitus is a complex disorder of the energy metabolism of the human body. In the last WHO/ADA classification, the main forms of this disease are Type 1 (T1DM) and Type 2 (T2DM) diabetes mellitus. According to the same classification, the pathogenesis of T2DM is considered to include a progressive insulin secretory defect on the background of insulin resistance. Recently, controversies surround the concept of peripheral insulin\r\nresistance emerging in the 70's as an attempt to explain the differences from the T1DM phenotype whose autoimmune nature was as that time revealed. The insulin resistance\r\nhypothesis was based on the supposition that high plasma insulin levels are the result of a primary molecular defect against which the normal beta cells will react with an increased insulin secretion. This hypothesis has been\r\nused to explain both the pathogenesis of T2DM and the metabolic syndrome, named also for a short period of time "the insulin resistance syndrome". We will try to argue\r\nthat what it is attributed to peripheral insulin\r\nresistance belongs in fact to obesity. Special emphasis is put on the role of the adipocytes, including the secretion of different adipokines with the secondary lipotoxicity, oxidative stress and pro-inflammatory reaction, explaining the complex relationship between obesity and diabetes.

Keywords: Insulin resistance / sensitivity, insulin receptor, type 2 diabetes, obesity.

Correspondence: C. Ionescu-T?rgoviste, MD ?N.C. Paulescu? National Institute of Diabetes, Nutrition and Metabolic Diseases, I. Movila str., 5-7 Bucharest 020475, Romania, E-mail: cit@paulescu.ro