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Published on: July 26, 2017

Combined inhibition of nitrergic and prostanoid pathways in J774 macrophages

S M Day1, J S McLean, J C Lockhart

  • 1University of Paisley, Paisley.

Clinical and Experimental Rheumatology
|November 13, 2003
PubMed
Abstract

Insights

Simultaneous inhibition of nitric oxide synthase (NOS) and cyclooxygenase (COX) pathways offers superior anti-inflammatory effects compared to inhibiting either pathway alone. This combined approach shows promise for treating inflammatory conditions like rheumatoid arthritis (RA).

Area of Science:

  • Biochemistry
  • Immunology
  • Pharmacology

Background:

  • Nitric oxide (NO) and prostaglandins are key mediators in the pathogenesis of inflammatory diseases, including rheumatoid arthritis (RA).
  • Understanding the interplay between these pathways is crucial for developing effective anti-inflammatory strategies.

Purpose of the Study:

  • To investigate the hypothesis that simultaneous inhibition of nitric oxide synthase (NOS) and cyclooxygenase (COX) provides greater anti-inflammatory effects than inhibiting either enzyme individually.
  • To evaluate the therapeutic potential of combined inhibition in inflammatory models.

Main Methods:

  • J774 macrophages were treated with L-NAME (NOS inhibitor) and/or indomethacin (COX inhibitor) before lipopolysaccharide (LPS) activation.
  • Nitrite (NO2-), prostaglandin E2 (PGE2), and tumor necrosis factor-alpha (TNF-alpha) levels were measured.
  • Quantitative real-time PCR was used to assess COX-2 gene expression.

Main Results:

  • LPS stimulation significantly increased NO2-, PGE2, and TNF-alpha levels.
  • L-NAME demonstrated a dose-dependent reduction in COX-2 expression.
  • Both L-NAME and indomethacin inhibited NO2- and PGE2 production in a dose-dependent manner.
  • Combined L-NAME and indomethacin treatment resulted in significantly greater inhibition of NO2- and PGE2 compared to individual treatments.

Conclusions:

  • The findings support the combined inhibition of the prostanoid and nitrergic systems as a viable anti-inflammatory treatment strategy.
  • This approach warrants further investigation in preclinical models of arthritis.

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