Visfatin, also known as pre-B cell colony enhancing factor (PBEF) is an adipocytokine belonging to the NAPRTase family and is produced and secreted primarily by white adipose tissue. Like insulin, Visfatin exerts hypoglycemic effects by interacting with the insulin receptor. Visfatin does not, however, compete with insulin for binding to this shared receptor and circulating levels of visfatin are much lower than that of insulin. Furthermore, the levels of visfatin are not influenced by food intake. The plasma Visfatin levels, like those of Leptin, correlate positively with the percent of body fat and increase during the development of obesity. The expression of Visfatin is upregulated by hypoxia, inflammation and hyperglycemia and downregulated by insulin, somatostatin and statins.