Nicotinamide phosphoribosyltransferase regulates cell survival through autophagy in cardiomyocytes

Autophagy. 2009 Nov;5(8):1229-31. doi: 10.4161/auto.5.8.10275. Epub 2009 Nov 8.

Abstract

Nicotinamide adenine dinucleotide (NAD(+)) acts as a transfer molecule for electrons, thereby acting as a key cofactor for energy production. NAD(+) also serves as a substrate for cellular enzymes, including poly (ADPribose) polymerase (PARP)-1 and Sirt1. Activation of PARP-1 by DNA damage depletes the cellular pool of NAD(+), leading to necrotic cell death. NAD(+) in the nucleus enhances the activity of Sirt1, thereby modulating transcription. NAD(+) is either synthesized de novo from amino acids, namely tryptophan and aspartic acid, or resynthesized from NAD(+) metabolites, such as nicotinamide (NAM), through the salvage pathway. NAM phosphoribosyltransferase (Nampt) is a rate-limiting enzyme in the NAD(+) salvage pathway. We have recently demonstrated that Nampt is an important regulator of NAD(+) and autophagy in cardiomyocytes. Here we discuss the role of Nampt in regulating autophagy and potential mechanisms by which NAD(+) regulates autophagy in the heart.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Autophagy*
  • Cell Line, Tumor
  • Cell Survival
  • Electron Transport
  • Humans
  • Mice
  • Models, Biological
  • Myocytes, Cardiac / cytology*
  • Myocytes, Cardiac / enzymology*
  • NAD / metabolism
  • Nicotinamide Phosphoribosyltransferase / metabolism*

Substances

  • NAD
  • Nicotinamide Phosphoribosyltransferase