Macrophage activation induces formation of the anti-inflammatory lipid cholesteryl-nitrolinoleate
Open accessAbstract
Nitroalkene derivatives of fatty acids act as adaptive, anti-inflammatory signalling mediators, based on their high-affinity PPARgamma (peroxisome-proliferator-activated receptor gamma) ligand activity and electrophilic reactivity with proteins, including transcription factors. Although free or esterified lipid nitroalkene derivatives have been detected in human plasma and urine, their generation by inflammatory stimuli has not been reported. In the present study, we show increased nitration of cholesteryl-linoleate by activated murine J774.1 macrophages, yielding the mononitrated nitroalkene CLNO2 (cholesteryl-nitrolinoleate). CLNO2 levels were found to increase approximately 20-fold 24 h after macrophage activation with Escherichia coli lipopolysaccharide plus interferon-gamma; this response was concurrent with an increase in the expression of NOS2 (inducible nitric oxide synthase) and was inhibited by the (*)NO (nitric oxide) inhibitor L-NAME (N(G)-nitro-L-arginine methyl ester). Macrophage (J774.1 and bone-marrow-derived cells) inflammatory responses were suppressed when activated in the presence of CLNO2 or LNO2 (nitrolinoleate). This included: (i) inhibition of NOS2 expression and cytokine secretion through PPARgamma and *NO-independent mechanisms; (ii) induction of haem oxygenase-1 expression; and (iii) inhibition of NF-kappaB (nuclear factor kappaB) activation. Overall, these results suggest that lipid nitration occurs as part of the response of macrophages to inflammatory stimuli involving NOS2 induction and that these by-products of nitro-oxidative reactions may act as novel adaptive down-regulators of inflammatory responses.
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The biological mechanisms accounting for fatty acid nitration and the specific structural characteristics of products remain to be defined.
“The biological mechanisms accounting for fatty acid nitration and the specific structural characteristics of products remain to be defined.”
From Conjugated linoleic acid is a preferential substrate for fatty acid nitration (2012) · cites this paper as [19]
In activated macrophages and rodent hearts subjected to ischemia-reoxygenation, inhibition of nitric-oxide synthase (NOS) activity suppresses fatty acid nitration by approximately 50%.
“In activated macrophages and rodent hearts subjected to ischemiareoxygenation, inhibition of nitric-oxide synthase (NOS) activity suppresses fatty acid nitration by ϳ50% (Fig. 3d) (19,47).”
From Conjugated linoleic acid is a preferential substrate for fatty acid nitration (2012) · cites this paper as [19]
Electrophilic lipids present in plants, generated by digestion of plant lipids, produced by oxidative inflammatory reactions or administered as pure synthetic homologs can regulate metabolism and the resolution of inflammatory processes.
“Consequently, electrophilic lipids which are present in plants, generated by digestion of plant lipids, produced by oxidative inflammatory reactions or administered as pure synthetic homologs [24], [26], [47], [56], can regulate metabolism and the resolution of inflammatory processes.”
From Olives and olive oil are sources of electrophilic fatty acid nitroalkenes (2014) · cites this paper as [24]
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- Authors
- Ferreira, A. M., Ferrari, M. I., Trostchansky, A., Batthyany, C., Souza, J. M., Alvarez, M. N., López, G. V., Baker, P. R. S., Schopfer, F. J., O'Donnell, V., Freeman, B. A., & Rubbo, H.
- Affiliations
- Universidad de la República de Uruguay (UY)
- Department of Biochemistry, Center for Free Radical and Biomedical Research, Faculty of Medicine, University of the Republic, Montevideo 11800, Uruguay
- University of Pittsburgh (US)
- Department of Medical Biochemistry, University of Wales College of Medicine, Cardiff CF14 4XN, U.K.
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, U.S.A.
- ORCID
- Venue
- Biochemical Journal
- Publisher
- Portland Press Ltd.
- Published
- 2008-12-12
- Volume
- 417
- Issue
- 1
- Pages
- 223-238
- ISSN
- 0264-6021 (ISSN-L)
- 1470-8728
- PMC
- PMC3290868
- OpenAlex
- W1991594689
- Cited by
- 78
- References
- 44
- Citations by year
- 2026: 2 · 2025: 1 · 2024: 1 · 2023: 1 · 2022: 2 · 2021: 2 · 2020: 2 · 2019: 8 · 2018: 7 · 2017: 6 · 2016: 7 · 2015: 4 · 2014: 4 · 2013: 5 · 2012: 4
- FWCI
- 6.95
- Type
- journal article
- Language
- en
- Open access
- green
- www.ncbi.nlm.nih.gov
- Locations
- Biochemical Journal (publishedVersion)
- PubMed (publishedVersion)
- PubMed Central (acceptedVersion)
- Funders
- Wellcome Trust
- National Heart, Lung, and Blood Institute (R01HL64937, R01HL064937, R37HL058115, R01HL058115, R01-HL-58115)
- Fogarty International Center (R03-TW007151)
- Topics
- Health Sciences › Nursing › Nutrition and Dietetics › Fatty Acid Research and Health
- Health Sciences › Medicine › Pharmacology › Inflammatory mediators and NSAID effects
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Peroxisome Proliferator-Activated Receptors
- Keywords
- macrophage activation, PPARγ, inducible nitric oxide synthase, nitric oxide, anti-inflammatory signaling, heme oxygenase-1, NF-κB, lipopolysaccharide, interferon-gamma, nitro-oxidative stress, J774.1 macrophages, bone marrow-derived macrophages, cytokine inhibition
- MeSH terms
- Animals, Cell Line, Cholesterol Esters, Enzyme Activation, Inflammation, Interferon-gamma, Lipopolysaccharides, Macrophage Activation, Macrophages, CD36 Antigens, NG-Nitroarginine Methyl Ester, Tumor Necrosis Factors, Heme Oxygenase-1, Nitric Oxide Synthase Type II, Interleukin-1beta
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