Inhibition by purine nucleotides of the release of reactive oxygen species from muscle mitochondria: indication for a function of uncoupling proteins as superoxide anion transporters

Biochem Biophys Res Commun. 2011 Apr 22;407(4):772-6. doi: 10.1016/j.bbrc.2011.03.098. Epub 2011 Mar 31.


Release of reactive oxygen species (ROS), measured as the sum of hydrogen peroxide (H₂O₂) and superoxide anion radical (O₂·⁻), from respiring rat heart and skeletal muscle mitochondria was significantly decreased by millimolar concentrations of GTP or GDP. Attempts to differentiate between the two forms of ROS showed that the release of O₂·⁻ rather than that of H₂O₂ was affected. Meanwhile, intramitochondrial ROS accumulation, measured by inactivation of aconitase, increased. These results suggest that guanine nucleotides inhibit the release of O₂·⁻ from mitochondria. As these nucleotides are known inhibitors of uncoupling proteins (UCPs), it is proposed that UCPs may function as carriers of O₂·⁻, thus enabling its removal from the matrix compartment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Female
  • Guanosine Diphosphate / pharmacology*
  • Guanosine Triphosphate / pharmacology*
  • Hydrogen Peroxide / metabolism
  • Ion Channels / antagonists & inhibitors
  • Ion Channels / metabolism*
  • Mitochondria, Muscle / drug effects*
  • Mitochondria, Muscle / metabolism
  • Mitochondrial Proteins / antagonists & inhibitors
  • Mitochondrial Proteins / metabolism*
  • Muscle, Skeletal / drug effects
  • Muscle, Skeletal / metabolism
  • Rats
  • Rats, Wistar
  • Reactive Oxygen Species / antagonists & inhibitors*
  • Reactive Oxygen Species / metabolism
  • Superoxides / antagonists & inhibitors
  • Superoxides / metabolism*
  • Uncoupling Protein 1


  • Ion Channels
  • Mitochondrial Proteins
  • Reactive Oxygen Species
  • Uncoupling Protein 1
  • Superoxides
  • Guanosine Diphosphate
  • Guanosine Triphosphate
  • Hydrogen Peroxide