Visfatin - new adipokine

Abstract

Fat tissue produces a variety of secreted proteins (adipocytokines) with important roles in metabolism and inflammation. Visfatin is a newly discovered adipocytokine expressed at high levels in both human and murine visceral fat. Its expression level in plasma increases during the development of obesity. Visfatin was confirmed to be identic to a protein described previously as PBEF (pre-B cell colony-enhancing factor), a 52-kilodalton cytokine expressed in lymphocytes. Visfatin stimulates glucose uptake by adipocyte and muscle cells in vitro and decreases blood glucose levels in mice. Notably, this insulinomimetic factor activates the insulin receptor by binding at a site distinct from that recognizing insulin. Further studies will be required to elucidate a role for visfatin and may lead to interesting insights into new therapies in a variety of inflammatory conditions in metabolic disorders such as diabetes.