5-oxo-6-8-11-14-eicosatetraenoic-acid and Asthma

5-Oxo-6,8,11,14-eicosatetraenoic acid (5-oxo-ETE) is an arachidonic acid metabolite formed by oxidation of the 5-lipoxygenase (5-LO) product 5S-hydroxy-6,8,11,14-eicosatetraenoic acid (5S-HETE) by the NADP

Topics: Animals; Anti-Asthmatic Agents; Arachidonic Acids; Asthma; Basement Membrane; Disease Models, Animal; Eosinophils; Granulocyte-Macrophage Colony-Stimulating Factor; Humans; Lipid Peroxidation; Molecular Targeted Therapy; Neutrophils; Receptors, Eicosanoid; Structure-Activity Relationship

5-Oxo-ETE (5-oxo-6,8,11,14-eicosatetraenoic acid) is formed from the 5-lipoxygenase product 5-HETE (5S-hydroxy-6,8,11,14-eicosatetraenoic acid) by 5-hydroxyeicosanoid dehydrogenase (5-HEDH). The cofactor NADP(+) is a limiting factor in the synthesis of 5-oxo-ETE because of its low concentrations in unperturbed cells. Activation of the respiratory burst in phagocytic cells, oxidative stress, and cell death all dramatically elevate both intracellular NADP(+) levels and 5-oxo-ETE synthesis. 5-HEDH is widely expressed in inflammatory, structural, and tumor cells. Cells devoid of 5-lipoxygenase can synthesize 5-oxo-ETE by transcellular biosynthesis using inflammatory cell-derived 5-HETE. 5-Oxo-ETE is a chemoattractant for neutrophils, monocytes, and basophils and promotes the proliferation of tumor cells. However, its primary target appears to be the eosinophil, for which it is a highly potent chemoattractant. The actions of 5-oxo-ETE are mediated by the highly selective OXE receptor, which signals by activating various second messenger pathways through the release of the βγ-dimer from Gi/o proteins to which it is coupled. Because of its potent effects on eosinophils, 5-oxo-ETE may be an important mediator in asthma, and, because of its proliferative effects, may also contribute to tumor progression. Selective OXE receptor antagonists, which are currently under development, could be useful therapeutic agents in asthma and other allergic diseases.

Topics: Animals; Arachidonate 5-Lipoxygenase; Arachidonic Acids; Asthma; Eosinophils; Humans; Neoplasms; Receptors, Eicosanoid; Signal Transduction; Structure-Activity Relationship

5-Oxo-ETE is a product of the 5-lipoxygenase pathway that is formed by the oxidation of 5-HETE by 5-hydroxyeicosanoid dehydrogenase (5-HEDH). 5-HEDH is a microsomal NADP(+)-dependent enzyme that is highly selective for 5-HETE. 5-Oxo-ETE synthesis is regulated by intracellular NADP(+) levels and is dramatically increased under conditions that favor oxidation of NADPH to NADP(+) such as oxidative stress and the respiratory burst in phagocytic cells. 5-Oxo-ETE is a potent chemoattractant for eosinophils and has similar effects on neutrophils, basophils and monocytes. It elicits infiltration of eosinophils and, to a lesser extent, neutrophils into the skin after intradermal injection in humans. It also promotes the survival of tumor cells and has been shown to block the induction of apoptosis by 5-LO inhibitors. 5-Oxo-ETE acts by the G(i/o)-coupled OXE receptor, which was also known as TG1019, R527 and hGPCR48. Although the pathophysiological role of 5-oxo-ETE is not well understood, it may play important roles in asthma and allergic diseases, cancer, and cardiovascular disease. The availability of a selective antagonist would help to clarify the role of 5-oxo-ETE and may be of therapeutic benefit.

Topics: Alcohol Oxidoreductases; Animals; Arachidonic Acids; Asthma; Cardiovascular Diseases; Cell Survival; Chemotactic Factors; Humans; Ligands; Neoplasms; Oxidative Stress; Receptors, Eicosanoid; Signal Transduction

To estimate the effect of prednisolone on 5-lipoxygenase activity in eosinophils obtained from asthmatic patients, cytosolic levels of 5-H(P)ETE and Ca2+ were measured in the eosinophils which were exposed to prednisolone in vitro and in vivo. The mean level of 5-H(P)ETE during a wheezing attack was significantly lower in the patients who had received intravenous prednisolone (500 mg/day). Incubation with prednisolone in vitro caused a dose-dependent decrease in the cytosolic levels of 5-H(P)ETE and Ca2+ in eosinophils obtained during the wheezing attack, but not in the eosinophils obtained from during remission. Results suggest that prednisolone inhibits the level of 5-H(P)ETE in the eosinophil cytosols of asthmatic patients during a wheezing attack, probably by inhibition of 5-lipoxygenase activity which is involved in the reduction of the influx of Ca2+.

Topics: Adult; Arachidonic Acids; Asthma; Calcium; Cytosol; Dose-Response Relationship, Drug; Eosinophils; Glucocorticoids; Humans; Injections, Intravenous; Leukocyte Count; Leukotriene C4; Male; Middle Aged; Prednisolone; Remission Induction; Respiratory Sounds

Topics: Anti-Asthmatic Agents; Arachidonic Acids; Asthma; Biological Products; Humans; Precision Medicine

The 5-lipoxygenase product 5-oxo-6,8,11,14-eicosatetraenoic acid (5-oxo-ETE) is the most powerful human eosinophil chemoattractant among lipid mediators and could play a major pathophysiological role in eosinophilic diseases such as asthma. Its actions are mediated by the OXE receptor, orthologs of which are found in many species from humans to fish, but not rodents. The unavailability of rodent models to examine the pathophysiological roles of 5-oxo-ETE and the OXE receptor has substantially hampered progress in this area. As an alternative, we have explored the possibility that the cat could serve as an appropriate animal model to investigate the role of 5-oxo-ETE. We found that feline peripheral blood leukocytes synthesize 5-oxo-ETE and that physiologically relevant levels of 5-oxo-ETE are present in bronchoalveolar lavage fluid from cats with experimentally induced asthma. 5-Oxo-ETE (EC50, 0.7nM) is a much more potent activator of actin polymerization in feline eosinophils than various other eicosanoids, including leukotriene (LT) B4 and prostaglandin D2. 5-Oxo-ETE and LTB4 induce feline leukocyte migration to similar extents at low concentrations (1nM), but at higher concentrations the response to 5-oxo-ETE is much greater. Although high concentrations of selective human OXE receptor antagonists blocked 5-oxo-ETE-induced actin polymerization in feline granulocytes, their potencies were about 200 times lower than for human granulocytes. We conclude that feline leukocytes synthesize and respond to 5-oxo-ETE, which could potentially play an important role in feline asthma, a common condition in this species. The cat could serve as a useful animal model to investigate the pathophysiological role of 5-oxo-ETE.

Topics: Actins; Allergens; Animals; Arachidonate 5-Lipoxygenase; Arachidonic Acids; Asthma; Benzeneacetamides; Benzothiazoles; Bronchoalveolar Lavage Fluid; Cats; Chemotaxis; Cynodon; Disease Models, Animal; Eosinophils; Female; Gene Expression; Humans; Leukotriene B4; Male; Neutrophils; Polymerization; Primary Cell Culture; Prostaglandin D2; Receptors, Eicosanoid

CCL11, CCL24, and CCL26 are chemokines involved in the recruitment of eosinophils into tissues and mainly activate CCR3. Whereas the genomic or pharmacological inhibition of CCR3 prevents the development of experimental asthma in rodents, it only impairs the recruitment of eosinophils by ∼40% in humans. As humans, but not rodents, express CCL26, we investigated the impact of CCL11, CCL24, and CCL26 on human eosinophils recruitment and evaluated the involvement of CCR3. The migration of eosinophils of healthy volunteers was similar for the three eotaxins. Eosinophils of mild asthmatics had a greater response to CCL11 and a much greater response to CCL26. Whereas all eotaxins induced the migration of eosinophil of asthmatics from 0 to 6 h, CCL26 triggered a second phase of migration between 12 and 18 h. Given that the CCR3 antagonists SB 328437 and SB 297006 inhibited the 5-oxo-eicosatetraenoate-induced migration of eosinophils and that the CCR3 antagonist UCB 35625 was not specific for CCR3, CCR3 blockade was performed with the CCR3 mAb. This antibody completely blocked the effect of all eotaxins on eosinophils of healthy subjects and the effect of CCL24 on the eosinophils of asthmatics. Interestingly, CCR3 blockade did not affect the second migration phase induced by CCL26 on eosinophils of asthmatics. In conclusion, CCL26 is a more effective chemoattractant than CCL11 and CCL24 for eosinophils of asthmatics. The mechanism of this greater efficiency is not yet defined. However, these results suggest that CCL26 may play a unique and important role in the recruitment of eosinophils in persistent asthma.

Topics: Antibodies, Monoclonal; Arachidonic Acids; Asthma; Benzamides; Cells, Cultured; Chemokine CCL11; Chemokine CCL24; Chemokine CCL26; Chemokines, CC; Chemotactic Factors; Chemotaxis, Leukocyte; Eosinophils; Humans; Interleukin-5; Naphthalenes; Phenylalanine; Receptors, CCR3; Recombinant Proteins; Time Factors; Xanthenes

Protectin D1 (PD1) is an anti-inflammatory and proresolving lipid mediator biosynthesized from the omega-3 fatty acid docosahexaenoic acid (DHA). Exogenous PD1 conferred protection against eosinophilic inflammation in animals with experimental asthma, although its endogenous cellular source and functions in human airways are of interest.. We sought to investigate the synthesizing capacity of PD1 in eosinophils from healthy subjects and patients with severe asthma and its direct effects on eosinophil functions.. Human eosinophil-derived metabolites of arachidonic acid and DHA were analyzed with liquid chromatography-tandem mass spectrometry-based lipidomic analysis. The biological activities of PD1 on the function of human eosinophils, including chemotaxis, adhesion molecule expressions, degranulation, superoxide anion generation, or survival, were examined.. We identified PD1 as one of the main anti-inflammatory and proresolving molecules synthesized in human eosinophils. PD1, in nanomolar concentrations, suppressed the chemotaxis induced by CCL11/eotaxin-1 or 5-oxo-eicosatetraenoic acid and modulated the expression of the adhesion molecules CD11b and L-selectin, although it had no effects on the degranulation, superoxide anion generation, or survival of the eosinophils. Compared with the cells harvested from healthy subjects, we observed a prominent decrease in the biosynthesis of PD1 by eosinophils from patients with severe asthma, even in presence of DHA.. These observations are a first indication that activated human eosinophils represent a major source of PD1, which can act as a self-resolving machinery in eosinophilic inflammation, whereas the production of PD1 is impaired in patients with severe asthma.

Topics: Adult; Aged; Anti-Inflammatory Agents; Arachidonic Acids; Asthma; Case-Control Studies; CD11b Antigen; Cell Adhesion Molecules; Chemokine CCL11; Chemotaxis; Docosahexaenoic Acids; Eosinophils; Female; Humans; Inflammation; L-Selectin; Male; Neutrophils; Superoxides

Asthma is associated with an eosinophil infiltration into the bronchial mucosa. 5-Oxo-6,8,11,14(E,Z,Z,Z)-eicosatetraenoic acid (5-oxo-ETE), a potent eosinophil chemotactic factor, activates cell motility, adherence, and proteolysis, notably, by promoting CD11b expression, matrix metalloproteinase (MMP)-9 secretion, and plasmin generation. We investigated the intracellular signaling pathways implicated in these various steps by using different, selective inhibitors. Human eosinophil migration through a reconstituted basement membrane in response to 5-oxo-ETE was greatly inhibited (>or=72%) by the protein kinase C (PKC)-delta, PKC-zeta, ERK-1/2, and p38 inhibitors. Our findings indicate that PKC-delta mediates cell motility, CD11b expression, and MMP-9 granule release. PKC-zeta is also largely involved in eosinophil migration, although its specific targets remain undefined. ERK-1/2 and p38 modulate CD11b expression; ERK-1/2 is also involved in long-term MMP-9 secretion and p38 in the plasmin activation system. We demonstrated the crucial implication of PKC-delta, PKC-zeta, ERK-1/2, and p38 in human blood eosinophil migration through extracellular matrix components. Targeting specific pathways may have therapeutic potential for the treatment of allergic airway inflammation.

Topics: Arachidonic Acids; Asthma; CD11b Antigen; Cell Movement; Eosinophils; Humans; Matrix Metalloproteinase 9; Mitogen-Activated Protein Kinase 3; p38 Mitogen-Activated Protein Kinases; Protein Kinase C; Protein Kinase C-delta; Protein Serine-Threonine Kinases; Signal Transduction

The eicosanoid 5-oxo-6E,8Z,11Z,14Z-eicosatetraenoic acid (5-oxo-ETE) has recently been identified as the ligand for the oxoeicosanoid (OXE) receptor. In vitro and in vivo studies have suggested that 5-oxo-ETE has a role in the asthmatic inflammatory response and it has been shown to stimulate eosinophil migration to the airways. New data suggest that eosinophils have an important role in the pathogenesis of asthma, being required for mucus accumulation, airway hyperresponsiveness and remodelling of the airways. However, there are several mediators that can stimulate the recruitment of eosinophils to the airways and the development of antagonists against the OXE receptor is required to evaluate the potential of the OXE receptor as a new therapeutic approach for asthma.

Topics: Animals; Arachidonate 5-Lipoxygenase; Arachidonic Acids; Asthma; Bronchial Hyperreactivity; Chemotactic Factors; Eosinophils; Humans; Inflammation; Models, Biological; Monocytes; Neutrophils

5-Oxo-6,8,11,14-eicosatetraenoic acid (5-oxo-ETE) is an arachidonic acid metabolite with potent in vitro chemoattractant effects on eosinophils and neutrophils. It has also been shown to induce pulmonary eosinophilia in Brown Norway rats, but it is not known whether it is active in human beings in vivo.. To determine whether 5-oxo-ETE can induce cellular infiltration in patients with atopic asthma and nonatopic control subjects after intradermal administration.. 5-Oxo-ETE was administered intradermally to 11 patients with atopic asthma and 10 nonatopic control subjects. Skin biopsy specimens were taken 6 or 24 hours later and examined by immunocytochemistry for cells expressing specific markers for eosinophils (major basic protein), neutrophils (elastase), macrophages (CD68), lymphocytes (CD3), and mast cells (tryptase).. 5-Oxo-ETE (1.5 and 5 microg) elicited the infiltration of both eosinophils and neutrophils into the skin in both control and atopic asthmatic subjects. Increased numbers of eosinophils were observed at 6 and 24 hours after injection, whereas significantly elevated neutrophil numbers were present only after 24 hours. Eosinophils were >3 times higher in patients with atopic asthma compared with control subjects after injection of the highest dose of 5-oxo-ETE. Macrophage numbers were also elevated, but only at the highest dose of 5-oxo-ETE. No effects were observed on the numbers of either lymphocytes or mast cells.. 5-Oxo-ETE elicits the infiltration of eosinophils and neutrophils into the skin of human beings in vivo after intradermal administration. Asthmatic subjects are more responsive to this substance than nonallergic control subjects. These results suggest that 5-oxo-ETE may be an important mediator of inflammation.

Topics: Arachidonic Acids; Asthma; Case-Control Studies; Cell Movement; Chemotactic Factors; Granulocytes; Humans; Macrophages; Mast Cells; Neutrophils; Skin; Time Factors

Tissue eosinophils express more membrane receptors and release more mediators than blood eosinophils, suggesting that migration from blood to tissue modulates eosinophil phenotype and functions.. We postulated that eosinophil passage through endothelial basement membrane, an important step of eosinophil migration into tissue, may be responsible for some of these changes.. We previously showed that 5-oxo-6, 8, 11, 14-eicosatetraenoic acid (5-oxo-ETE) in combination with IL-5 promotes eosinophil migration through Matrigel, a mouse tumour cell-derived basement membrane. Using this model, we evaluated the effect of trans-Matrigel migration on purified human blood eosinophil expressions of CD44, CD69 and HLA-DR that either increase or appear on activated eosinophils, and releases of peroxidase (EPO), leukotriene (LT) C(4) and granulocyte-monocyte colony stimulating factor (GM-CSF).. IL-5, but not 5-oxo-ETE, increased eosinophil expression of CD44 and CD69. Migration of eosinophils through Matrigel significantly increased CD44 expression level over the one induced by IL-5 (P = 0.0001). Migration through Matrigel did not modify CD69 expression compared with the one obtained in the presence of IL-5 alone; however, incubation of eosinophils on Matrigel decreased IL-5-induced CD69 (P = 0.0001). Trans-Matrigel migration did not modify HLA-DR expression, nor EPO, LTC(4) and GM-CSF releases.. These data show that in vitro trans-Matrigel migration and Matrigel contact modulate eosinophil membrane receptor expression. Consequently, they suggest that migration through basement membrane mediates changes in cell-surface phenotype observed on activated eosinophils and probably prepares them for interactions with tissue components and cells.

Topics: Adolescent; Adult; Arachidonic Acids; Asthma; Basement Membrane; Biocompatible Materials; Cell Movement; Collagen; Cytokines; Drug Combinations; Eosinophils; Female; Forced Expiratory Volume; Granulocyte-Macrophage Colony-Stimulating Factor; Humans; Hyaluronan Receptors; Inflammation Mediators; Interleukin-5; Laminin; Male; Middle Aged; Predictive Value of Tests; Proteoglycans; Receptors, Cell Surface

The effect of eotaxin, a potent eosinophil chemotactic factor, on eosinophil transmigration through a reconstituted basal membrane (Matrigel) was evaluated. Eotaxin induced significant eosinophil transmigration in the presence of 10% fetal bovine serum (FBS) and interleukin-5. Its effect was optimal at 0.01 microM, and it plateaued at 18 h. Eotaxin's effect was greater with eosinophils from asthmatic subjects (61.1 +/- 3.4%) than with eosinophils from normal subjects (38.7 +/- 4.2%) (P < 0.001). Inhibition of metalloproteinases decreased eotaxin-induced transmigration by < or = 10.4%, whereas inhibition of the plasminogen-plasmin system decreased eotaxin's effect by < or = 44.4% (P = 0.0002). Moreover, eotaxin-induced transmigration was largely diminished in medium with low concentrations of serum [0.5% FBS: 6.1 +/- 2.4%; 10% FBS: 40.2 +/- 5.8% (P = 0.0001)] but returned to its initial level with the addition of plasminogen (2 U/mL) to 0.5% FBS (43.1 +/- 6.5%). These data show that eotaxin is an efficient promoter of eosinophil transmigration in vitro, that it is more potent with cells from asthmatics than with normal cells, and that its effect depends predominantly on the activation of the plasminogen-plasmin system.

Topics: Adult; Arachidonic Acids; Asthma; Cell Movement; Chemokine CCL11; Chemokines, CC; Chemotactic Factors, Eosinophil; Collagen; Cytokines; Dose-Response Relationship, Drug; Drug Combinations; Enzyme Activation; Eosinophils; Female; Fibrinolysin; Humans; Hydroxamic Acids; Kinetics; Laminin; Male; Matrix Metalloproteinase Inhibitors; Plasminogen; Platelet Activating Factor; Proteoglycans; Receptors, CCR3; Receptors, Cell Surface; Receptors, Chemokine; Receptors, Urokinase Plasminogen Activator

Basement membrane transmigration is an important step in tissue recruitment of eosinophils into inflamed tissue. Recent reports showed that this phenomenon is modulated by platelet-activating factor (PAF) in combination with cytokines and proteinases. We investigated the in vitro efficacy of 5-oxo-6,8,11, 14-eicosatetraenoic acid (5-oxo-ETE), a metabolite of arachidonic acid and known as a potent eosinophil chemotactic factor, in promoting the transmigration of blood eosinophils from normal and asthmatic subjects through a Matrigel basement membrane. 5-Oxo-ETE proved to be a more potent (> 10-fold) inducer of eosinophil transmigration than PAF, and this effect was similar in cells from normal and asthmatic subjects (82.0 +/- 3.7% and 88.1 +/- 3.7%, respectively). Moreover, 5-oxo-ETE was active in the absence of interleukin (IL)-5, although this cytokine amplified the effect of 5-oxo-ETE from 61.3 +/- 3.3% to 92.8 +/- 1.8% (p = 0.003). The membrane receptor for urokinase plasminogen activator (CD87), a serine protease, was observed on eosinophils, and its expression was increased by IL-5. The inhibition of both metalloproteinases (MMP) and plasmin/plasminogen complex with inhibitor or monoclonal antibodies decreased cell transmigration by about 50%. Combination of an MMP inhibitor with anti-CD87 antibodies had no additive effect. These data show that 5-oxo-ETE is an efficient promoter of eosinophil transmigration in vitro, and is much more potent in this respect than PAF. The data suggest that 5-oxo-ETE could play an important role in eosinophil recruitment in vivo. Moreover, they demonstrate that in addition to MMP, the plasmin/plasminogen system could be involved in eosinophil transmigration.

Topics: Adult; Arachidonic Acids; Asthma; Basement Membrane; Cell Movement; Chemotactic Factors; Collagenases; Dose-Response Relationship, Drug; Eosinophils; Female; Humans; Hydroxamic Acids; Interleukin-5; Male; Matrix Metalloproteinase 9; Matrix Metalloproteinase Inhibitors; Metalloendopeptidases; Platelet Activating Factor; Receptors, Cell Surface; Receptors, Urokinase Plasminogen Activator; Time Factors; Urokinase-Type Plasminogen Activator