Ischemia-induced interleukin-6 as a potential endogenous neuroprotective cytokine against NMDA receptor-mediated excitoxicity in the brain

Carine All, Olivier Nicole, Fabian Docagne, Sylvain Lesne, Eric T. MacKenzie, André Nouvelot, Alain Buisson, Denis Vivien

Research output: Contribution to journalArticlepeer-review

160 Scopus citations

Abstract

In the brain, the expression of the pleiotropic cytokine interleukin-6 (IL-6) is enhanced in various chronic or acute central nervous system disorders. However, the significance of IL-6 production in such neuropathologic states remains controversial. The present study investigated the role of IL-6 after cerebral ischemia. First, the authors showed that focal cerebral ischemia in rats early up-regulated the expression of IL-6 mRNA, without affecting the transcription of its receptors (IL-6Rα and gp130). Similarly, the striatal injection of N-methyl-D-aspartate (NMDA) in rats, a paradigm of excitotoxic injury, activated the expression of IL-6 mRNA. The involvement of glutamatergic receptor activation was further investigated by incubating cortical neurons with NMDA or α-amino-3-hydroxy- 5-methyl-4-isoxazolepropionate (AMPA). NMDA and ionomycin (a calcium ionophore) up-regulated IL-6 mRNA, suggesting that neurons may produce IL-6 in response to the calcium influx mediated through NMDA receptors. The potential role of IL-6 during ischemic/excitotoxic insults was then studied by testing the effect of IL-6 against apoptotic or excitotoxic challenges in cortical cultures. IL-6 did not prevent serum deprivation- or staurosporine- induced apoptotic neuronal death, or AMPA/kainate-mediated excitotoxicity. However, in both mixed and pure neuronal cultures, IL-6 dose-dependently protected neurons against NMDA toxicity. This effect was blocked by a competitive inhibitor of IL-6. Overall, the results suggest that the up- regulation of IL-6 induced by cerebral ischemia could represent an endogenous neuroprotective mechanism against NMDA receptor-mediated injury.

Original languageEnglish (US)
Pages (from-to)956-966
Number of pages11
JournalJournal of Cerebral Blood Flow and Metabolism
Volume20
Issue number6
DOIs
StatePublished - 2000

Keywords

  • Excitotoxicity
  • Focal cerebral ischemia
  • Interleukin-6
  • Neuroprotection
  • Primary cortical neuronal culture

Fingerprint Dive into the research topics of 'Ischemia-induced interleukin-6 as a potential endogenous neuroprotective cytokine against NMDA receptor-mediated excitoxicity in the brain'. Together they form a unique fingerprint.

Cite this