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Updated: Jul 17, 2026
08:32
Application of Genetically Encoded Fluorescent Nitric Oxide (NO•) Probes, the geNOps, for Real-time Imaging of NO• Signals in Single Cells
Published on: March 16, 2017
Oxalomalate affects the inducible nitric oxide synthase expression and activity
Carlo Irace1, Giuseppe Esposito, Carmen Maffettone
1Dipartimento di Farmacologia Sperimentale, Università di Napoli Federico II, via D. Montesano 49, 80131-Napoli, Italy.
Life Sciences
|January 30, 2007
Summary
Oxalomalate (OMA) reduces nitric oxide (NO) production by inhibiting inducible nitric oxide synthase (iNOS) synthesis and increasing its degradation. This suggests OMA
Area of Science:
- Biochemistry
- Molecular Biology
- Pharmacology
Background:
- Inducible nitric oxide synthase (iNOS) produces nitric oxide (NO) during inflammation.
- iNOS synthesis and activity are influenced by factors like heme and L-arginine.
- Dysregulated NO production is implicated in various pathological conditions.
Purpose of the Study:
- To investigate the effect of oxalomalate (OMA) on iNOS expression and activity.
- To explore OMA's potential role in modulating NO overproduction.
Main Methods:
- Utilized lipopolysaccharide (LPS)-activated J774 macrophages and LPS-stimulated rats.
- Assessed nitrite production, iNOS protein and mRNA levels.
- Employed Western blot analysis, (35)S-metabolic labeling, and enzymatic assays.
- Investigated the impact of Krebs cycle intermediates (alpha-ketoglutarate, succinyl-CoA) and protein synthesis inhibitors (cycloheximide).
Main Results:
- OMA inhibited nitrite production and iNOS protein expression in LPS-activated macrophages and rats, without affecting iNOS mRNA.
- OMA reduced iNOS biosynthesis and increased its degradation rate.
- Alpha-ketoglutarate or succinyl-CoA reversed OMA's effect on NO production.
- OMA directly inhibited iNOS enzymatic activity.
Conclusions:
- Oxalomalate modulates iNOS through regulating its synthesis, catalytic activity, and degradation.
- OMA demonstrates potential as a therapeutic agent to reduce pathological NO overproduction.
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