Nicotinamide phosphoribosyltransferase (Nampt; pre-B cell colony-enhancing factor; PBEF; Visfatin) is an 52kD adipokine secreted by adipose tissue and involved in the biosynthesis of nicotinamide adenine dinucleotide (NAD+). Two forms of Nampt exist, an intracellular form (iNampt) and an extracellular form (eNampt). While the function of iNampt as an essential and rate-limiting NAD+ biosynthetic enzyme is well established, the physiological role of eNampt is still a matter of debate. Nampt has various functions, including the promotion of vascular smooth muscle cell maturation and inhibition of neutrophil apoptosis. It activates insulin receptor and has insulin-mimetic effects, lowering blood glucose and improving insulin sensitivity. The protein is highly expressed in visceral fat and serum levels of the protein correlate with obesity.
Biological Activity:
Shows adipogenic effects in stimulated differentiating 3T3-L1 cells.
Sequence:
Intracellular human Nampt (visfatin/PBEF) (aa 1-491) is fused at the C-terminus to a His-tag.
Storage and Stability:
Short-term Storage: +4 degrees C
Long-term Storage: -20 degrees C
Working aliquots are stable for up to 3 months when stored at -20 degrees C.