Expression and regulation of nampt in human islets.
Nicotinamide phosphoribosyltransferase (Nampt) is a rate-limiting enzyme in the mammalian NAD+ biosynthesis of a salvage pathway and exists in 2 known forms, intracellular Nampt (iNampt) and a secreted form, extracellular Nampt (eNampt).eNampt can generate an intermediate product, nicotinamide mononucleotide (NMN), which has been reported to suppor