The putative essential nutrient pyrroloquinoline quinone is neuroprotective in a rodent model of hypoxic/ischemic brain injury

Neuroscience. 1994 Sep;62(2):399-406. doi: 10.1016/0306-4522(94)90375-1.


Pyrroloquinoline quinone is a ubiquitous redox cofactor and putative essential nutrient in mammals. Pyrroloquinoline quinone has recently been demonstrated to depress N-methyl-D-asparate induced electrical responses and is neuroprotective in vitro. In addition, pyrroloquinoline quinone has been demonstrated to act as a free radical scavenger in mammalian tissues. In this study, we demonstrate a neuroprotective effect of pyrroloquinoline quinone in an in vivo cerebral hypoxia/ischemia model in the rodent. Significant reduction in infarct size resulted from pyrroloquinoline quinone pretreatment and also when pyrroloquinoline quinone was administered following induction of hypoxia/ischemia. The neuroprotective effect was not dependent on change in core or cranial temperatures, as there was no difference between temperature measurements in pyrroloquinoline quinone-treated and vehicle-treated controls. No changes in electroencephalographic activity were observed at neuroprotective doses. These findings suggest that pyrroloquinoline quinone may represent a novel class of quinoid reagents of potential use in the treatment of neurological disorders that involve excitotoxicity. This study demonstrates a protective effect of the novel essential nutrient pyrroloquinoline quinone on brain injury in a rodent model of cerebral hypoxia/ischemia. Pyrroloquinoline quinone was neuroprotective when administered before and even after the insult, and did not appear to have significant neurobehavioral side effects. Pyrroloquinoline quinone represents a new class of agents with potential use in the therapy of stroke.

Publication types

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

MeSH terms

  • Animals
  • Brain / drug effects*
  • Brain / physiology
  • Brain / physiopathology
  • Brain Ischemia / physiopathology
  • Brain Ischemia / prevention & control*
  • Cerebral Infarction / pathology
  • Cerebral Infarction / physiopathology
  • Coenzymes / pharmacology
  • Dose-Response Relationship, Drug
  • Electroencephalography / drug effects
  • Free Radical Scavengers / pharmacology
  • Hypoxia, Brain / physiopathology
  • Hypoxia, Brain / prevention & control*
  • PQQ Cofactor
  • Quinolones / pharmacology*
  • Rats


  • Coenzymes
  • Free Radical Scavengers
  • Quinolones
  • PQQ Cofactor