Abstract

Fat tissue produces a variety of secreted proteins with important roles in metabolism. Isolated and newly identified adipocytokine - visfatin is highly enriched in the visceral fat and it's expression level in plasma increases during the development of obesity. Visfatin exerts insulin - mimetic effects and lowers plasma glucose level throughout binding and activating the insulin receptor in animal model. However studies in humans' subjects reported conflicting results in regard to its relation with adiposity, insulin resistance, dyslipidemia, suggesting that the role of this protein in the development of obesity and insulin resistance is unclear. Visfatin - the cytokine-like protein pre-B cell colony - enhancing factor 1 was also identified as cytosolic nicotinamide phosphoribosyltransferase. This enzyme is involved in nicotinamide adenine dinucleotide (NAD) biosynthesis, related to the glucose and lipid metabolism in humans. Further study of visfatin's physiological may lead to new insights into glucose homeostasis an and or new therapies not only for metabolic disorders but also for disturbance of the immune system.