| Oxidative and nitrative modifications of enkephalins by human neutrophils: effect of nitroenkephalin on leukocyte functional responses. | |
| | |
MedLine Citation:
|
PMID: 22113643 Owner: NLM Status: Publisher |
Abstract/OtherAbstract:
|
Neutrophils play a major role in acute inflammation by generating reactive oxygen/nitrogen species. Opioid peptides, including enkephalins, are present at inflammation sites. Neutrophils contribute to protect against inflammatory pain by releasing opioid peptides. In this investigation, the ability of human polymorphonuclear cells to induce oxidative and nitrative modifications of Leu-enkephalin has been investigated in vitro. Activated human neutrophils mediate the oxidation of Leu-enkephalin resulting in the production of dienkephalin. In the presence of nitrite at concentrations observed during inflammatory and infectious process (10-50 μM), nitroenkephalin, a nitrated derivative of Leu-enkephalin, is additionally formed. The yield of nitroenkephalin increases with nitrite concentration and is significantly inhibited by the addition of catalase or 4-aminobenzoic acid hydrazide (ABAH), a specific inhibitor of peroxidases. These results suggest that neutrophils induce nitration of Leu-enkephalin by a mechanism that is dependent on myeloperoxidase activity and hydrogen peroxide. Oxidative/nitrative modifications of Leu-enkephalin have been also evidenced when cells were treated with the NO-donor molecule, DEANO. The nitrated enkephalin has been examined for its effect on leukocyte functional responses. The data reveal that nitroenkephalin at micromolar concentrations inhibits superoxide anion generation and degranulation of azurophilic granules of human polymorphonuclear cells. Moreover, nitroenkephalin inhibits spontaneous apoptosis of neutrophils, as evaluated by measuring caspase-3 activity. Collectively, our data indicate that the nitrated enkephalin attenuates neutrophil activation and promotes the short-term survival of these cells, suggesting a possible role of the nitrocompound in the efficiency and resolution of inflammatory processes. |
| | |
Authors:
|
Elisabetta Capuozzo; Laura Pecci; Federica Giovannitti; Alessia Baseggio Conrado; Mario Fontana |
Related Documents
:
|
16239913 - Growth factors and antiapoptotic signaling pathways in multiple myeloma. 19079863 - Vitamin d3 and the immune system: maintaining the balance in health and disease. 4350403 - Macrophage nonimmunologic recognition: target cell factors related to contact inhibition. |
Publication Detail:
|
Type: JOURNAL ARTICLE Date: 2011-11-24 |
Journal Detail:
|
Title: Amino acids Volume: - ISSN: 1438-2199 ISO Abbreviation: - Publication Date: 2011 Nov |
Date Detail:
|
Created Date: 2011-11-24 Completed Date: - Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 9200312 Medline TA: Amino Acids Country: - |
Other Details:
|
Languages: ENG Pagination: - Citation Subset: - |
Affiliation:
|
Dipartimento di Scienze Biochimiche "A. Rossi Fanelli", Istituto di Biologia e Patologia Molecolari del CNR, Sapienza Università di Roma, P.le Aldo Moro 5, 00185, Rome, Italy. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
|
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: [Nursing care experiences of a borderline personality patient with spiritual distress].
Next Document: Molecular dynamics simulation exploration of unfolding and refolding of a ten-amino acid miniprotein...