title: Review: NAD +: a modulator of immune functions.
abstract: Latterly, nicotinamide adenine dinucleotide (NAD+) has emerged as a molecule with versatile functions and of enormous impact on the maintenance of cell integrity. Besides playing key roles in almost all major aspects of energy metabolism, there is mounting evidence that NAD+ and its degradation products affect various biological activities including calcium homeostasis, gene transcription, DNA repair, and intercellular communication. This review is aimed at giving a brief insight into the life cycle of NAD+ in the cell, referring to synthesis, action and degradation aspects. With respect to their immunological relevance, the importance and function of the major NAD+ metabolizing enzymes, namely CD38/CD157, ADP-ribosyltransferases (ARTs), poly-ADP-ribose-polymerases (PARPs), and sirtuins are summarized and roles of NAD+ and its main degradation product adenosine 5'-diphosphoribose (ADPR) in cell signaling are discussed. In addition, an outline of the variety of immunological processes depending on the activity of nicotinamide phosphoribosyltransferase (Nampt), the key enzyme of the salvage pathway of NAD+ synthesis, is presented. Taken together, an efficient supply of NAD+ seems to be a crucial need for a multitude of cell functions, underlining the yet only partly revealed potency of this small molecule to influence cell fate.
authors.affiliation: Department of Immunobiology, Institute of Biology, University of Leipzig, Talstrasse 33, Leipzig, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Grahnert
authors.forename: Anja
authors.initials: A
authors.lastname: Grahnert
authors.forename: Carina
authors.initials: C
authors.lastname: Klein
authors.forename: Erik
authors.initials: E
authors.lastname: Schilling
authors.forename: Janine
authors.initials: J
authors.lastname: Wehrhahn
authors.forename: Sunna
authors.initials: S
authors.lastname: Hauschildt
mesh_terms: D036002:ADP Ribose Transferases / Q000276:immunology; D000818:Animals; D002450:Cell Communication; D004734:Energy Metabolism / Q000276:immunology; D006801:Humans; D056747:Immunomodulation; D009243:NAD / Q000276:immunology*; D054409:Nicotinamide Phosphoribosyltransferase / Q000378:metabolism; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D037761:Sirtuins / Q000378:metabolism
chemical_list: D009243:NAD; D036002:ADP Ribose Transferases; D054409:Nicotinamide Phosphoribosyltransferase; D011065:Poly(ADP-ribose) Polymerases; D037761:Sirtuins