Insulin Resistance

Abstract

The twin epidemic of ‘Diabesity’-diabetes and obesity, all over the world, both in developed and developing countries, has brought the issue of insulin resistance (IR) into new focus of research. Apart from Type 2 diabetes mellitus (DM), IR is implicated in many other clinical syndromes because of its varied metabolic and mitogenic actions. IR has been found to play important pivotal role in pathophysiology of diabesity. IR is defined as when a normal or higher insulin level fails to produce expected biological response; one predominantly affecting insulin mediated glucose disposal 20–30% reduction in the number of insulin receptors on the target cells is observed in majority of Type 2 DM patients but 1/3 of the patients may not manifest loss of number of receptors; therefore, defective post-receptor signalling is considered as the main cause of IR. Main sites of IR are liver, adipose tissue and skeletal muscles. Apart from Type 2 DM, many other clinical and genetic syndromes are associated with IR.