Visfatin was originally cloned as a putative cytokine shown to enhance the maturation of B cell precursors in the presence of Interleukin (IL)-7 and stem cell factor, it was therefore named “pre-B cell colony-enhancing factor” (PBEF). Visfatin refer to an identical protein, as judged by its amino acid sequence, with multiple biological functions. Visfatin is a nicotinamide phosphoribosyltransferase (Nampt) enzyme that catalyzes first step in the biosynthesis of NAD from nicotinamide. This protein has also been reported to be a cytokine (PBEF) that promotes B cell maturation and inhibits neutrophil apoptosis, or a visceral-fat derived hormone (visfatin) that acts by binding and activating the insulin receptor.