NAD+ repletion prevents PARP-1-induced glycolytic blockade and cell death in cultured mouse astrocytes

Biochem Biophys Res Commun. 2003 Sep 5;308(4):809-13. doi: 10.1016/s0006-291x(03)01483-9.


Poly(ADP-ribose) polymerase-1 (PARP-1) is a nuclear enzyme that is involved in DNA repair and activated by DNA damage. When activated, PARP-1 consumes NAD(+) to form ADP-ribose polymers on acceptor proteins. Extensive activation of PARP-1 leads to glycolytic blockade, energy failure, and cell death. These events have been postulated to result from NAD(+) depletion. Here, we used primary astrocyte cultures to directly test this proposal, utilizing the endogenous expression of connexin-43 hemichannels by astrocytes to manipulate intracellular NAD(+) concentrations. Activation of PARP-1 with the DNA alkylating agent N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) produced NAD(+) depletion, glycolytic blockade, and cell death. Cultures incubated in high (10mM) extracellular concentrations of NAD(+) after MNNG exposure showed normalization of intracellular NAD(+) concentrations. Repletion of intracellular NAD(+) in this manner completely restored glycolytic capacity and prevented cell death. These results suggest that NAD(+) depletion is the cause of glycolytic failure after PARP-1 activation.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Astrocytes / cytology
  • Astrocytes / metabolism*
  • Astrocytes / pathology
  • Cell Death
  • Cell Survival
  • Cells, Cultured
  • Connexin 43 / metabolism
  • DNA Damage
  • DNA Repair
  • Dose-Response Relationship, Drug
  • Enzyme Activation
  • Glucose / metabolism
  • Glycolysis
  • Methylnitronitrosoguanidine / pharmacology
  • Mice
  • Mice, Knockout
  • NAD / metabolism*
  • Poly(ADP-ribose) Polymerases / metabolism*


  • Connexin 43
  • NAD
  • Methylnitronitrosoguanidine
  • Poly(ADP-ribose) Polymerases
  • Glucose