The effect of nitric oxide on cytokine-induced release of PGE2 by human cultured astroglial cells

Vincenzo Mollace, Marco Colasanti, Carolina Muscoli, Giuliana M. Lauro, Michelangelo Iannone, Domenicantonio Rotiroti, Giuseppe Nistico'

Research output: Contribution to journalArticle

Abstract

1. The role of the L-arginine-nitric oxide (NO) pathway on the formation of prostaglandin E2 (PGE2) by human cultured astroglial cells incubated with interleukin-1β (IL-1β) and tumour necrosis factor-α (TNF-α) was investigated. 2. Incubation of T 67 astroglial cell line with IL-β (10 ng ml-1) and TNF-α (500 u ml-1) produced a significant (P <0.05) increase of both nitrite (the breakdown product of NO), cyclic GMP and PGE2 levels in cell supernatants. Nω-nitro-L-arginine methyl ester (L-NAME; 20-300 μM), an inhibitor of NO synthase (NOS), inhibited the increase of cyclic GMP and nitrite levels found in supernatants of cytokine-treated astroglial cells and reduced the release of PGE2. The latter effect showed that the enhanced arachidonic acid (AA) metabolism subsequent to stimulation of astroglial cells with IL-1β and TNF-α was, at least in part, induced by NO. This occurred also when sodium nitroprusside (SNP; 120 μM), an NO donor, was incubated with astroglial cells, an effect antagonized by oxyhaemoglobin (OxyHb; 10 μM). 3. The inhibition elicited by L-NAME on PGE2-release by cytokine-treated astroglial cells was reversed by adding AA (40 μM), showing that the effect of NO on cytokine-dependent PGE2 release occurred at the cyclo-oxygenase (COX) level. Furthermore, the release of PGE2 in cytokine-treated astroglial cells was inhibited by indomethacin (10 μM), a COX inhibitor as well as by preincubating cells with dexamethasone (20 μM), an inhibitor of inducible enzymes, showing that the inducible isoform of COX (COX-2) was involved. 4. On the other hand, pretreating astroglial cells with methylene blue (MB; 10 μM), an inhibitor of NO biological activity acting at the guanylate cyclase level, failed to affect PGE2 release in cytokine-treated astroglial cells, leading to the conclusion that cyclic GMP changes related to NO formation are not involved in the generation of AA metabolites. 5. The present experiments demonstrated that the release of PGE2 by astroglial cells pretreated with IL-1β and TNF-α is due to enhanced COX-2 activity via activation of the L-arginine-NO pathway, and this may be relevant to the understanding of the pathophysiological mechanisms underlying neuroimmune disorders.

Original languageEnglish
Pages (from-to)742-746
Number of pages5
JournalBritish Journal of Pharmacology
Volume124
Issue number4
DOIs
Publication statusPublished - 1998

Keywords

  • Cyclo-oxygenase
  • Cytokines
  • Neuroimmune disorders
  • Nitric oxide
  • Prostaglandins

ASJC Scopus subject areas

  • Pharmacology

Fingerprint Dive into the research topics of 'The effect of nitric oxide on cytokine-induced release of PGE2 by human cultured astroglial cells'. Together they form a unique fingerprint.

  • Cite this

    Mollace, V., Colasanti, M., Muscoli, C., Lauro, G. M., Iannone, M., Rotiroti, D., & Nistico', G. (1998). The effect of nitric oxide on cytokine-induced release of PGE2 by human cultured astroglial cells. British Journal of Pharmacology, 124(4), 742-746. https://doi.org/10.1038/sj.bjp.0701852