The impact of erythropoietin on short-term changes in phosphorylation of brain protein kinases in a rat model of traumatic brain injury

Samuel Valable, Gilles Francony, Pierre Bouzat, Marie Cécile Fevre, Nouara Mahious, Valentine Bouet, Régine Farion, Emmanuel Barbier, Hana Lahrech, Chantal Remy, Edwige Petit, Christoph Segebarth, Myriam Bernaudin, Jean François Payen

Research output: Contribution to journalArticlepeer-review

Abstract

We found that recombinant human erythropoietin (rhEPO) reduced significantly the development of brain edema in a rat model of diffuse traumatic brain injury (TBI) (impact-acceleration model). In this study, we investigated the molecular and intracellular changes potentially involved in these immediate effects. Brain tissue nitric oxide (NO) synthesis, phosphorylation level of two protein kinases (extracellular-regulated kinase (ERK)-1/-2 and Akt), and brain water content were measured 1 (H1) and 2 h (H2) after insult. Posttraumatic administration of rhEPO (5,000 IU/kg body weight, intravenously, 30 mins after injury) reduced TBI-induced upregulation of ERK phosphorylation, although it increased Akt phosphorylation at H1. These early molecular changes were associated with a reduction in brain NO synthesis at H1 and with an attenuation of brain edema at H2. Intraventricular administration of the ERK-1/-2 inhibitor, U0126, or the Akt inhibitor, LY294002, before injury showed that ERK was required for brain edema formation, and that rhEPO-induced reduction of edema could involve the ERK pathway. These results were obtained in the absence of any evidence of blood-brain barrier damage on contrast-enhanced magnetic resonance images. The findings of our study indicate that the anti edematous effect of rhEPO could be mediated through an early inhibition of ERK phosphorylation after diffuse TBI.

Original languageEnglish (US)
Pages (from-to)361-369
Number of pages9
JournalJournal of Cerebral Blood Flow and Metabolism
Volume30
Issue number2
DOIs
StatePublished - Feb 2010

Keywords

  • Brain trauma
  • Cerebral edema
  • EPO (erythropoietin)
  • Inhibitors
  • MAPK (mitogen-activated protein kinase)
  • MAPK activation after brain trauma

ASJC Scopus subject areas

  • Neurology
  • Clinical Neurology
  • Cardiology and Cardiovascular Medicine

Fingerprint Dive into the research topics of 'The impact of erythropoietin on short-term changes in phosphorylation of brain protein kinases in a rat model of traumatic brain injury'. Together they form a unique fingerprint.

Cite this