Mechanisms of Insulin Resistance Development in Obesity: Literature Review

The article reviews the literature data on the mechanisms of insulin resistance development that are formed in obesity. The presence of abdominal obesity and the associated features of functioning in visceral adipose tissue are considered as risk factors and mechanisms of insulin resistance development. Excessive carbohydrate intake with food and a change in the direction of Randle cycle activity are also analyzed as one of the mechanisms of insulin resistance development not only in obesity, but also in thin, apparently healthy people, but with developed visceral obesity. The accumulation of biologically active lipids (long-chain acyl-CoA, diacylglycerol (DAG), ceramides) and free fatty acids is studied, which can lead to disruption of signaling along the insulin signaling pathway and glucose transport through carrier proteins (GLUT4). Also, inflammation of adipose tissue is considered, namely the role of macrophages and some cytokines: tumor necrosis factor α, IL-6 and IL-1β, in reducing the conduction of insulin signals. The supposed role of vitamin D deficiency, which develops in obesity, in the formation of insulin resistance is described. Also, the disruption of the production of adpiokines: adiponectin, leptin and resistin is considered.