Insulin signaling in adipose tissue plays an important role in lipid storage and regulation of glucose homeostasis. However, in obesity-associated hyperinsulinemia insulin also mediates deleterious effects as demonstrated by the work of David J. Pedersen and colleagues.
The authors found that high circulating insulin significantly promotes adipose tissue inflammation, including increased macrophage expansion and expression of cytokines. Even in lean mice, infusion of insulin under constant euglycemic conditions stimulated expression of cytokines. Their findings indicate that obesity-associated hyperinsulinemia is a major contributing factor in driving adipose tissue inflammation, which in turn may contribute to obesity-induced insulin resistance and type 2 diabetes.Full Text