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Hoshi RA, Alotaibi M, Liu Y, Watrous JD, Ridker PM, Glynn RJ, Serhan CN, Luttmann-Gibson H, Moorthy MV, Jain M, Demler OV, Mora S. One-Year Effects of High-Intensity Statin on Bioactive Lipids: Findings From the JUPITER Trial. Arterioscler Thromb Vasc Biol 2024; 44:e196-e206. [PMID: 38841856 PMCID: PMC11209760 DOI: 10.1161/atvbaha.124.321058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Accepted: 05/22/2024] [Indexed: 06/07/2024]
Abstract
BACKGROUND Statin effects extend beyond low-density lipoprotein cholesterol reduction, potentially modulating the metabolism of bioactive lipids (BALs), crucial for biological signaling and inflammation. These bioactive metabolites may serve as metabolic footprints, helping uncover underlying processes linked to pleiotropic effects of statins and yielding a better understanding of their cardioprotective properties. This study aimed to investigate the impact of high-intensity statin therapy versus placebo on plasma BALs in the JUPITER trial (Justification for the Use of Statins in Prevention: an Intervention Trial Evaluating Rosuvastatin; NCT00239681), a randomized primary prevention trial involving individuals with low-density lipoprotein cholesterol <130 mg/dL and high-sensitivity C-reactive protein ≥2 mg/L. METHODS Using a nontargeted mass spectrometry approach, over 11 000 lipid features were assayed from baseline and 1-year plasma samples from cardiovascular disease noncases from 2 nonoverlapping nested substudies: JUPITERdiscovery (n=589) and JUPITERvalidation (n=409). The effect of randomized allocation of rosuvastatin 20 mg versus placebo on BALs was examined by fitting a linear regression with delta values (∆=year 1-baseline) adjusted for age and baseline levels of each feature. Significant associations in discovery were analyzed in the validation cohort. Multiple comparisons were adjusted using 2-stage overall false discovery rate. RESULTS We identified 610 lipid features associated with statin randomization with significant replication (overall false discovery rate, <0.05), including 26 with annotations. Statin therapy significantly increased levels of 276 features, including BALs with anti-inflammatory activity and arterial vasodilation properties. Concurrently, 334 features were significantly lowered by statin therapy, including arachidonic acid and proinflammatory and proplatelet aggregation BALs. By contrast, statin therapy reduced an eicosapentaenoic acid-derived hydroxyeicosapentaenoic acid metabolite, which may be related to impaired glucose metabolism. Additionally, we observed sex-related differences in 6 lipid metabolites and 6 unknown features. CONCLUSIONS Statin allocation was significantly associated with upregulation of BALs with anti-inflammatory, antiplatelet aggregation and antioxidant properties and downregulation of BALs with proinflammatory and proplatelet aggregation activity, supporting the pleiotropic effects of statins beyond low-density lipoprotein cholesterol reduction.
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Affiliation(s)
- Rosangela Akemi Hoshi
- Division of Cardiovascular Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Division of Preventive Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Center for Lipid Metabolomics, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Mona Alotaibi
- Department of Medicine, University of California San Diego, La Jolla, CA 92037, USA
- Division of Pulmonary, Critical Care and Sleep Medicine, University of California San Diego, La Jolla, CA, USA
| | - Yanyan Liu
- Division of Preventive Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Center for Lipid Metabolomics, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Jeramie D. Watrous
- Department of Medicine, University of California San Diego, La Jolla, CA 92037, USA
| | - Paul M Ridker
- Division of Cardiovascular Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Division of Preventive Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Robert J. Glynn
- Division of Preventive Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Charles N. Serhan
- Center for Experimental Therapeutics and Reperfusion Injury, Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Heike Luttmann-Gibson
- Division of Cardiovascular Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Division of Preventive Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Center for Lipid Metabolomics, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - M. Vinayaga Moorthy
- Division of Preventive Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Mohit Jain
- Department of Medicine, University of California San Diego, La Jolla, CA 92037, USA
| | - Olga V. Demler
- Division of Preventive Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Center for Lipid Metabolomics, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Department of Computer Science, ETH Zurich, Zurich 8092, Switzerland
| | - Samia Mora
- Division of Cardiovascular Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Division of Preventive Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Center for Lipid Metabolomics, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
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An JU, Song YS, Kim KR, Ko YJ, Yoon DY, Oh DK. Biotransformation of polyunsaturated fatty acids to bioactive hepoxilins and trioxilins by microbial enzymes. Nat Commun 2018; 9:128. [PMID: 29317615 PMCID: PMC5760719 DOI: 10.1038/s41467-017-02543-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Accepted: 12/08/2017] [Indexed: 12/18/2022] Open
Abstract
Hepoxilins (HXs) and trioxilins (TrXs) are involved in physiological processes such as inflammation, insulin secretion and pain perception in human. They are metabolites of polyunsaturated fatty acids (PUFAs), including arachidonic acid, eicosapentaenoic acid and docosahexaenoic acid, formed by 12-lipoxygenase (LOX) and epoxide hydrolase (EH) expressed by mammalian cells. Here, we identify ten types of HXs and TrXs, produced by the prokaryote Myxococcus xanthus, of which six types are new, namely, HXB5, HXD3, HXE3, TrXB5, TrXD3 and TrXE3. We succeed in the biotransformation of PUFAs into eight types of HXs (>35% conversion) and TrXs (>10% conversion) by expressing M. xanthus 12-LOX or 11-LOX with or without EH in Escherichia coli. We determine 11-hydroxy-eicosatetraenoic acid, HXB3, HXB4, HXD3, TrXB3 and TrXD3 as potential peroxisome proliferator-activated receptor-γ partial agonists. These findings may facilitate physiological studies and drug development based on lipid mediators. Hepoxilins (HXs) and trioxilins (TrXs) are lipid metabolites with roles in inflammation and insulin secretion. Here, the authors discover a prokaryotic source of HXs and TrXs, identify the biosynthetic enzymes and heterologously express HXs and TrXs in E. coli.
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Affiliation(s)
- Jung-Ung An
- Department of Integrative Bioscience and Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 05029, Republic of Korea
| | - Yong-Seok Song
- Department of Integrative Bioscience and Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 05029, Republic of Korea
| | - Kyoung-Rok Kim
- Department of Integrative Bioscience and Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 05029, Republic of Korea
| | - Yoon-Joo Ko
- National Center for Inter-University Research Facilities (NCIRF), Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Do-Young Yoon
- Department of Integrative Bioscience and Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 05029, Republic of Korea
| | - Deok-Kun Oh
- Department of Integrative Bioscience and Biotechnology, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 05029, Republic of Korea.
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Pace-Asciak CR. Pathophysiology of the hepoxilins. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1851:383-96. [DOI: 10.1016/j.bbalip.2014.09.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 09/06/2014] [Accepted: 09/10/2014] [Indexed: 10/24/2022]
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Kubala SA, Patil SU, Shreffler WG, Hurley BP. Pathogen induced chemo-attractant hepoxilin A3 drives neutrophils, but not eosinophils across epithelial barriers. Prostaglandins Other Lipid Mediat 2013; 108:1-8. [PMID: 24315875 DOI: 10.1016/j.prostaglandins.2013.11.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Revised: 11/08/2013] [Accepted: 11/21/2013] [Indexed: 12/19/2022]
Abstract
Pathogen induced migration of neutrophils across mucosal epithelial barriers requires epithelial production of the chemotactic lipid mediator, hepoxilin A3 (HXA3). HXA3 is an eicosanoid derived from arachidonic acid. Although eosinophils are also capable of penetrating mucosal surfaces, eosinophilic infiltration occurs mainly during allergic processes whereas neutrophils dominate mucosal infection. Both neutrophils and eosinophils can respond to chemotactic gradients of certain eicosanoids, however, it is not known whether eosinophils respond to pathogen induced lipid mediators such as HXA3. In this study, neutrophils and eosinophils were isolated from human blood and placed on the basolateral side of polarized epithelial monolayers grown on permeable Transwell filters and challenged by various chemotactic gradients of distinct lipid mediators. We observed that both cell populations migrated across epithelial monolayers in response to a leukotriene B4 (LTB4) gradient, whereas only eosinophils migrated toward a prostaglandin D2 (PGD2) gradient. Interestingly, while pathogen induced neutrophil trans-epithelial migration was substantial, pathogen induced eosinophil trans-epithelial migration was not observed. Further, gradients of chemotactic lipids derived from pathogen infected epithelial cells known to be enriched for HXA3 as well as purified HXA3 drove significant numbers of neutrophils across epithelial barriers, whereas eosinophils failed to respond to these gradients. These data suggest that although the eicosanoid HXA3 serves as an important neutrophil chemo-attractant at mucosal surfaces during pathogenic infection, HXA3 does not appear to exhibit chemotactic activity toward eosinophils.
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Affiliation(s)
- S A Kubala
- Department of Pediatrics, Harvard Medical School, Boston, MA 02115, United States; Center for Immunology and Inflammatory Diseases and the Food Allergy Center, Massachusetts General Hospital, Charlestown, MA 02129, United States
| | - S U Patil
- Center for Immunology and Inflammatory Diseases and the Food Allergy Center, Massachusetts General Hospital, Charlestown, MA 02129, United States
| | - W G Shreffler
- Department of Pediatrics, Harvard Medical School, Boston, MA 02115, United States; Center for Immunology and Inflammatory Diseases and the Food Allergy Center, Massachusetts General Hospital, Charlestown, MA 02129, United States
| | - B P Hurley
- Department of Pediatrics, Harvard Medical School, Boston, MA 02115, United States; Mucosal Immunology & Biology Research Center, Massachusetts General Hospital, Charlestown, MA 02129, United States.
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Protective effects of dietary EPA and DHA on ischemia–reperfusion-induced intestinal stress. J Nutr Biochem 2013; 24:104-11. [DOI: 10.1016/j.jnutbio.2012.02.014] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Revised: 02/21/2012] [Accepted: 02/28/2012] [Indexed: 02/02/2023]
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Innate immunity modulation by the IL-33/ST2 system in intestinal mucosa. BIOMED RESEARCH INTERNATIONAL 2012; 2013:142492. [PMID: 23484079 PMCID: PMC3591220 DOI: 10.1155/2013/142492] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Accepted: 10/29/2012] [Indexed: 12/23/2022]
Abstract
Innate immunity prevents pathogens from entering and spreading within the body. This function is especially important in the gastrointestinal tract and skin, as these organs have a large surface contact area with the outside environment. In the intestine, luminal commensal bacteria are necessary for adequate food digestion and play a crucial role in tolerance to benign antigens. Immune system damage can create an intestinal inflammatory response, leading to chronic disease including inflammatory bowel diseases (IBD). Ulcerative colitis (UC) is an IBD of unknown etiology with increasing worldwide prevalence. In the intestinal mucosa of UC patients, there is an imbalance in the IL-33/ST2 axis, an important modulator of the innate immune response. This paper reviews the role of the IL-33/ST2 system in innate immunity of the intestinal mucosa and its importance in inflammatory bowel diseases, especially ulcerative colitis.
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Tamang DL, Pirzai W, Priebe GP, Traficante DC, Pier GB, Falck JR, Morisseau C, Hammock BD, McCormick BA, Gronert K, Hurley BP. Hepoxilin A(3) facilitates neutrophilic breach of lipoxygenase-expressing airway epithelial barriers. THE JOURNAL OF IMMUNOLOGY 2012; 189:4960-9. [PMID: 23045615 DOI: 10.4049/jimmunol.1201922] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A feature shared by many inflammatory lung diseases is excessive neutrophilic infiltration. Neutrophil homing to airspaces involve multiple factors produced by several distinct cell types. Hepoxilin A(3) is a neutrophil chemoattractant produced by pathogen-infected epithelial cells that is hypothesized to facilitate neutrophil breach of mucosal barriers. Using a Transwell model of lung epithelial barriers infected with Pseudomonas aeruginosa, we explored the role of hepoxilin A(3) in neutrophil transepithelial migration. Pharmacological inhibitors of the enzymatic pathways necessary to generate hepoxilin A(3), including phospholipase A(2) and 12-lipoxygenase, potently interfere with P. aeruginosa-induced neutrophil transepithelial migration. Both transformed and primary human lung epithelial cells infected with P. aeruginosa generate hepoxilin A(3) precursor arachidonic acid. All four known lipoxygenase enzymes capable of synthesizing hepoxilin A(3) are expressed in lung epithelial cell lines, primary small airway epithelial cells, and human bronchial epithelial cells. Lung epithelial cells produce increased hepoxilin A(3) and lipid-derived neutrophil chemotactic activity in response to P. aeruginosa infection. Lipid-derived chemotactic activity is soluble epoxide hydrolase sensitive, consistent with hepoxilin A(3) serving a chemotactic role. Stable inhibitory structural analogs of hepoxilin A(3) are capable of impeding P. aeruginosa-induced neutrophil transepithelial migration. Finally, intranasal infection of mice with P. aeruginosa promotes enhanced cellular infiltrate into the airspace, as well as increased concentration of the 12-lipoxygenase metabolites hepoxilin A(3) and 12-hydroxyeicosa-5Z,8Z,10E,14Z-tetraenoic acid. Data generated from multiple models in this study provide further evidence that hepoxilin A(3) is produced in response to lung pathogenic bacteria and functions to drive neutrophils across epithelial barriers.
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Affiliation(s)
- David L Tamang
- Mucosal Immunology Laboratory, Massachusetts General Hospital, Charlestown, MA 02129, USA
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Spinal 12-lipoxygenase-derived hepoxilin A3 contributes to inflammatory hyperalgesia via activation of TRPV1 and TRPA1 receptors. Proc Natl Acad Sci U S A 2012; 109:6721-6. [PMID: 22493235 DOI: 10.1073/pnas.1110460109] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Peripheral inflammation initiates changes in spinal nociceptive processing leading to hyperalgesia. Previously, we demonstrated that among 102 lipid species detected by LC-MS/MS analysis in rat spinal cord, the most notable increases that occur after intraplantar carrageenan are metabolites of 12-lipoxygenases (12-LOX), particularly hepoxilins (HXA(3) and HXB(3)). Thus, we examined involvement of spinal LOX enzymes in inflammatory hyperalgesia. In the current work, we found that intrathecal (IT) delivery of the LOX inhibitor nordihydroguaiaretic acid prevented the carrageenan-evoked increase in spinal HXB(3) at doses that attenuated the associated hyperalgesia. Furthermore, IT delivery of inhibitors targeting 12-LOX (CDC, Baicalein), but not 5-LOX (Zileuton) dose-dependently attenuated tactile allodynia. Similarly, IT delivery of 12-LOX metabolites of arachidonic acid 12(S)-HpETE, 12(S)-HETE, HXA(3), or HXB(3) evoked profound, persistent tactile allodynia, but 12(S)-HpETE and HXA(3) produced relatively modest, transient heat hyperalgesia. The pronociceptive effect of HXA(3) correlated with enhanced release of Substance P from primary sensory afferents. Importantly, HXA(3) triggered sustained mobilization of calcium in cells stably overexpressing TRPV1 or TRPA1 receptors and in acutely dissociated rodent sensory neurons. Constitutive deletion or antagonists of TRPV1 (AMG9810) or TRPA1 (HC030031) attenuated this action. Furthermore, pretreatment with antihyperalgesic doses of AMG9810 or HC030031 reduced spinal HXA(3)-evoked allodynia. These data indicate that spinal HXA(3) is increased by peripheral inflammation and promotes initiation of facilitated nociceptive processing through direct activation of TRPV1 and TRPA1 at central terminals.
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Boll EJ, Struve C, Sander A, Demma Z, Krogfelt KA, McCormick BA. Enteroaggregative Escherichia coli promotes transepithelial migration of neutrophils through a conserved 12-lipoxygenase pathway. Cell Microbiol 2011; 14:120-32. [PMID: 21951973 DOI: 10.1111/j.1462-5822.2011.01706.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Enteroaggregative Escherichia coli (EAEC) induces release of pro-inflammatory markers and disruption of intestinal epithelial barriers in vitro, suggesting an inflammatory aspect to EAEC infection. However, the mechanisms underlying EAEC-induced mucosal inflammatory responses and the extent to which these events contribute to pathogenesis is not well characterized. Employing an established in vitro model we demonstrated that EAEC prototype strain 042 induces migration of polymorphonuclear neutrophils (PMNs) across polarized T84 cell monolayers. This event was mediated through a conserved host cell signalling cascade involving the 12/15-LOX pathway and led to apical secretion of an arachidonic acid-derived lipid PMN chemoattractant, guiding PMNs across the epithelia to the site of infection. Moreover, supporting the hypothesis that inflammatory responses may contribute to EAEC pathogenesis, we found that PMN transepithelial migration promoted enhanced attachment of EAEC 042 to T84 cells. These findings suggest that EAEC-induced PMN infiltration may favour colonization and thus pathogenesis of EAEC.
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Affiliation(s)
- Erik J Boll
- Department of Microbiological Surveillance and Research, Statens Serum Institut, Denmark
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Cronin A, Decker M, Arand M. Mammalian soluble epoxide hydrolase is identical to liver hepoxilin hydrolase. J Lipid Res 2011; 52:712-9. [PMID: 21217101 DOI: 10.1194/jlr.m009639] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Hepoxilins are lipid signaling molecules derived from arachidonic acid through the 12-lipoxygenase pathway. These trans-epoxy hydroxy eicosanoids play a role in a variety of physiological processes, including inflammation, neurotransmission, and formation of skin barrier function. Mammalian hepoxilin hydrolase, partly purified from rat liver, has earlier been reported to degrade hepoxilins to trioxilins. Here, we report that hepoxilin hydrolysis in liver is mainly catalyzed by soluble epoxide hydrolase (sEH): i) purified mammalian sEH hydrolyses hepoxilin A₃ and B₃ with a V(max) of 0.4-2.5 μmol/mg/min; ii) the highly selective sEH inhibitors N-adamantyl-N'-cyclohexyl urea and 12-(3-adamantan-1-yl-ureido) dodecanoic acid greatly reduced hepoxilin hydrolysis in mouse liver preparations; iii) hepoxilin hydrolase activity was abolished in liver preparations from sEH(-/-) mice; and iv) liver homogenates of sEH(-/-) mice show elevated basal levels of hepoxilins but lowered levels of trioxilins compared with wild-type animals. We conclude that sEH is identical to previously reported hepoxilin hydrolase. This is of particular physiological relevance because sEH is emerging as a novel drug target due to its major role in the hydrolysis of important lipid signaling molecules such as epoxyeicosatrienoic acids. sEH inhibitors might have undesired side effects on hepoxilin signaling.
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Affiliation(s)
- Annette Cronin
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland.
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Biosynthesis of 14,15-Hepoxilins in Human L1236 Hodgkin Lymphoma Cells and Eosinophils. Lipids 2010; 46:69-79. [DOI: 10.1007/s11745-010-3485-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2010] [Accepted: 09/28/2010] [Indexed: 10/18/2022]
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Mumy KL, McCormick BA. The role of neutrophils in the event of intestinal inflammation. Curr Opin Pharmacol 2009; 9:697-701. [PMID: 19854677 DOI: 10.1016/j.coph.2009.10.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2009] [Revised: 10/05/2009] [Accepted: 10/06/2009] [Indexed: 01/21/2023]
Abstract
The transmigration of polymorphonuclear leukocytes (PMNs; neutrophils) into the intestinal lumen is a classical phenomenon associated with a wide variety of disease states, including those of both pathogenic and autoimmune/idiopathic origin. While PMNs are highly effective at killing invading pathogens by releasing microbiocidal products, excessive or unnecessary release of these substances can cause substantial damage to the intestinal epithelium. Therefore, it is necessary to understand the underlying mechanisms that lure neutrophils into the lumen allowing them to perform their desired functions, so that researchers may begin to identify which processes may be potential targets for inhibiting the transmigration of PMNs during noninfectious states.
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Affiliation(s)
- Karen L Mumy
- The Department of Molecular Genetics and Microbiology, University of Massachusetts Medical School, Worcester, MA, USA
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Abstract
The hepoxilin pathway was discovered over two decades ago. Products in this pathway are derived through the 12S-lipoxygenase/hepoxilin synthase enzyme system and contain intrinsic biological activity. This activity relates to the reorganization of calcium and potassium ions within the cell, and in inflammation and insulin secretion. Although the natural hepoxilins are chemically unstable, chemical analogues (PBTs) have been synthesized with chemical and biological stability. The PBTs antagonize the natural hepoxilins. The PBTs showed bioavailability, excellent tolerance and stability in vivo. In proof of principle studies in vivo in animal models, the PBTs have shown actions as anti-inflammatory agents, anti-thrombotic agents, anti-cancer agents and anti-diabetic agents. These studies demonstrate the effectiveness of the base structure of the hepoxilin (and PBT) molecule and serve as an excellent framework for the design and preparation of second-generation compounds with improved pharmaceutical properties as therapeutics for the above-mentioned diseases.
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Affiliation(s)
- Cecil R Pace-Asciak
- Programme in Physiology and Experimental Medicine, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada.
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Distinct isoforms of phospholipase A2 mediate the ability of Salmonella enterica serotype typhimurium and Shigella flexneri to induce the transepithelial migration of neutrophils. Infect Immun 2008; 76:3614-27. [PMID: 18505810 DOI: 10.1128/iai.00407-08] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Salmonella spp. and Shigella spp. are responsible for millions of cases of enteric disease each year worldwide. While these pathogens have evolved distinct strategies for interacting with the human intestinal epithelium, they both induce significant proinflammatory responses that result in massive transepithelial migration of neutrophils across the intestinal mucosa. It has previously been shown with Salmonella enterica serotype Typhimurium that the process of neutrophil transmigration is mediated in part by the secretion of hepoxilin A(3) (HXA(3); 8-hydroxy-11,12-epoxy-eicosatetraenoic acid), a potent neutrophil chemoattractant, from the apical surface of infected model intestinal epithelium. This study confirms that HXA(3) is also secreted in response to infection by Shigella flexneri, that it is produced by a pathway involving 12/15-lipoxygenase (12/15-LOX), and that S. enterica serovar Typhimurium and S. flexneri share certain elements in the mechanism(s) that underlies the otherwise separate signal transduction pathways that are engaged to induce polymorphonuclear leukocyte (PMN) transepithelial migration (protein kinase C and extracellular signal-regulated kinases 1 and 2, respectively). PMN transepithelial migration in response to infection with S. flexneri was dependent on 12/15-LOX activity, the enzyme responsible for the initial metabolism of arachidonic acid to HXA(3). Probing further into this pathway, we also found that S. enterica serovar Typhimurium and S. flexneri activate different subtypes of phospholipase A(2), a critical enzyme involved in the liberation of arachidonic acid from cellular membranes. Thus, although S. enterica serovar Typhimurium and S. flexneri utilize different mechanisms for triggering the induction of PMN transepithelial migration, we found that their reliance on 12/15-LOX is conserved, suggesting that enteric pathogens may ultimately stimulate similar pathways for the synthesis and release of HXA(3).
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Hurley BP, Sin A, McCormick BA. Adhesion molecules involved in hepoxilin A3-mediated neutrophil transepithelial migration. Clin Exp Immunol 2007; 151:297-305. [PMID: 18005361 DOI: 10.1111/j.1365-2249.2007.03551.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
A common feature underlying active states of inflammation is the migration of neutrophils (PMNs) from the circulation and across a number of tissue barriers in response to chemoattractant stimuli. Although our group has recently established a discreet role for the PMN chemoattractant, hepoxilin A3 (HXA3) in the process of PMN recruitment, very little is known regarding the interaction of HXA3 with PMNs. To characterize further the event of HXA3-induced PMN transepithelial migration, we sought to determine the adhesion molecules required for migration across different epithelial surfaces (T84 intestinal and A549 airway cells) relative to two well-studied PMN chemoattractants, formyl-methionyl-leucyl-phenylalanine (fMLP) and leukotriene B4 (LTB4). Our findings reveal that the adhesion interaction profile of PMN transepithelial migration in response to HXA3 differs from the adhesion interaction profile exhibited by the structurally related eicosanoid LTB4. Furthermore, unique to PMN transepithelial migration induced by gradients of HXA3 was the critical dependency of all four major surface adhesion molecules examined (i.e. CD18, CD47, CD44 and CD55). Our results suggest that the particular chemoattractant gradient imposed, as well as the type of epithelial cell monolayer, each plays a role in determining the adhesion molecules involved in transepithelial migration. Given the complexities of these interactions, our findings are important to consider with respect to adhesion molecules that may be targeted for potential drug development.
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Affiliation(s)
- B P Hurley
- Mucosal Immunology Laboratory, Department of Pediatric Gastroenterology and Nutrition, Massachusetts General Hospital, Boston, MA 02129, USA
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Nigam S, Zafiriou MP, Deva R, Ciccoli R, Roux-Van der Merwe R. Structure, biochemistry and biology of hepoxilins. FEBS J 2007; 274:3503-3512. [PMID: 17608719 DOI: 10.1111/j.1742-4658.2007.05910.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Hepoxilins are biologically relevant epoxy-hydroxy eicosanoids synthesized through the 12S-lipoxygenase (12S-LOX) pathway of the arachidonic acid (AA) metabolism. The pathway is bifurcated at the level of 12S-hydroperoxy-eicosatetraenoic acid (12S-HpETE), which can either be reduced to 12S-hydro-eicosatetraenoic acid (12S-HETE) or converted to hepoxilins. The present review gives an update on the biochemistry, biology and clinical aspects of hepoxilin-based drug development. The isolation, cloning and characterization of a rat leukocyte-type 12S-LOX from rat insulinoma RINm5F cells revealed a 12S-LOX possessing an intrinsic 8S/R-hydroxy-11,12-epoxyeicosa-5Z,9E,14Z-trienoic acid (HXA(3)) synthase activity. Site-directed mutagenesis studies on rat 12S-LOX showed that the HXA(3) synthase activity was impaired when the positional specificity of AA was altered. Interestingly, amino acid Leu353, and not conventional sequence determinants Met419 and Ile418, was found to be a crucial sequence determinant for AA oxygenation. The regulation of HXA(3) formation is dependent on the cellular overall peroxide tone. Cellular glutathione peroxidases (cGPxs) compete with HXA(3) synthase for 12S-HpETE as substrate either to reduce to 12S-HETE or to convert to HXA(3), respectively. Therefore, RINm5F cells, which are devoid of GPxs, are capable of converting AA or 12S-HpETE to HXA(3) under basal conditions, whereas cells overexpressing cGPx are unable to do so. HXA(3) exhibits a myriad of biological effects, most of which are associated with the stimulation of intracellular calcium or the transport of calcium across the membrane. The activation of HXA(3)-G-protein-coupled receptors explains many of the extracellular effects of HXA(3), including AA- and diacylglycerol (DAG) release in human neutrophils, insulin secretion in rat pancreatic beta-cells or islets, and synaptic actions in the brain. The availability of stable analogs of HXA(3), termed 10-hydroxy-11,12-cyclopropyl-eicosa-5Z,8Z,14Z-trienoic acid derivatives (PBTs), recently made several animal studies possible and explored the role of HXA(3) as a therapeutic in treatment of diseases. Thus, PBT-3 induced apoptosis in K562 tumour cells and inhibited growth of K562 CML solid tumours in nude mice. HXA(3) inhibited bleomycin-evoked lung fibrosis and inflammation in mice and the raised insulin level in the circulation of rats. At low glucose concentrations (0-3 mm), HXA(3) also stimulated insulin secretion in RINm5F cells through the activation of IRE1alpha, an endoplasmic reticulum-resident kinase. The latter regulates the protein folding for insulin biosynthesis. In conclusion, HXA(3)-mediated signaling may be involved in normal physiological functions, and hepoxilin-based drugs may serve as therapeutics in diseases such as type II diabetes and idiopathic lung fibrosis.
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Affiliation(s)
- Santosh Nigam
- Eicosanoid & Lipid Research Division and Centre for Experimental Gynecology & Breast Research, Charité- University Medical Centre Benjamin Franklin, Berlin, Germany
| | - Maria-Patapia Zafiriou
- Eicosanoid & Lipid Research Division and Centre for Experimental Gynecology & Breast Research, Charité- University Medical Centre Benjamin Franklin, Berlin, Germany
| | - Rupal Deva
- Eicosanoid & Lipid Research Division and Centre for Experimental Gynecology & Breast Research, Charité- University Medical Centre Benjamin Franklin, Berlin, Germany
| | - Roberto Ciccoli
- Eicosanoid & Lipid Research Division and Centre for Experimental Gynecology & Breast Research, Charité- University Medical Centre Benjamin Franklin, Berlin, Germany
| | - Renate Roux-Van der Merwe
- Eicosanoid & Lipid Research Division and Centre for Experimental Gynecology & Breast Research, Charité- University Medical Centre Benjamin Franklin, Berlin, Germany
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Abstract
Bacterial infections at epithelial surfaces, such as those that line the gut and the lung, stimulate the migration of neutrophils through the co-ordinated actions of chemoattractants secreted from pathogen-stimulated epithelial cells. One such factor involved in attracting polymorphonuclear leukocytes across the epithelium and into the lumen has until recently remained elusive. In 2004, we identified the eicosanoid, hepoxilin A(3), to be selectively secreted from the apical surface of human intestinal or lung epithelial cells stimulated with Salmonella enterica serotype Typhimurium or Pseudomonas aeruginosa, respectively. In this role, the function of hepoxilin A(3) is to guide neutrophils, via the establishment of a gradient, across the epithelial tight junction complex. Interestingly, interruption of the synthetic pathway of hepoxilin A(3) blocks the apical release of hepoxilin A(3)in vitro and the transmigration of neutrophils induced by S. typhimurium both in in vitro and in vivo models of inflammation. Such results have led to the discovery of a completely novel pathway that is not only critical for responses to bacterial pathogens but also has broad implications for inflammatory responses affecting mucosal surfaces in general. Thus, the objective of this review was to highlight the recent findings that implicate hepoxilin A(3) as a key regulator of mucosal inflammation.
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Affiliation(s)
- Beth A McCormick
- Department of Pediatric Gastroenterology, Massachusetts General Hospital, and Department of Microbiology and Molecular Genetics, Harvard Medical School, Charlestown, MA, USA
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19
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Nigam S, Zafiriou MP. Hepoxilin A3 synthase. Biochem Biophys Res Commun 2005; 338:161-8. [PMID: 16198304 DOI: 10.1016/j.bbrc.2005.09.065] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2005] [Accepted: 09/13/2005] [Indexed: 11/15/2022]
Abstract
Hepoxilins constitute a group of 12S-hydroperoxyeicosatetraenoic acid (12S-HpETE)-derived epoxy-hydroxy fatty acids that have been detected in various cell types and tissues. Although hepoxilin A3 (HXA3) exhibits a myriad of biological activities, its biosynthetic mechanism was not investigated in detail. Here we review the isolation, cloning, and characterization of a leukocyte-type 12S-lipoxygenase (12S-LOX) from rat insulinoma cells RINm5F, which exhibits an intrinsic hepoxilin A3 synthase activity. Confirmation for this observation was achieved by coimmunoprecipitation of HXA3 synthase activity with an anti-leukocyte 12S-LOX antibody, preparation of recombinant rat 12S-LOX enzyme from RINm5F cells, and assay of HXA3 synthase activity therein. Site-directed mutagenesis studies performed on rat 12S-LOX showed that 12-lipoxygenating enzyme species exhibit a strong HXA3 synthase activity that is impaired when the positional specificity of arachidonic acid is altered in favor of 15-lipoxygenation. Inasmuch as cellular glutathione peroxidases (cGPx and PHGPx) and HXA3 synthase compete for the same substrate 12S-HpETE, it can be proposed that the overall activity of glutathione peroxidases, representing the overall peroxide tone, finely tunes the rate of HXA3 formation.
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Affiliation(s)
- Santosh Nigam
- Eicosanoid and Lipid Research Division, Centre of Experimental Gynecology and Breast Research, University Medical Centre Berlin, Charité-Campus Benjamin Franklin, D-12200 Berlin, Germany.
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20
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Bogatcheva NV, Sergeeva MG, Dudek SM, Verin AD. Arachidonic acid cascade in endothelial pathobiology. Microvasc Res 2005; 69:107-27. [PMID: 15896353 DOI: 10.1016/j.mvr.2005.01.007] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2004] [Revised: 01/21/2005] [Accepted: 01/26/2005] [Indexed: 01/26/2023]
Abstract
Arachidonic acid (AA) and its metabolites (eicosanoids) represent powerful mediators, used by organisms to induce and suppress inflammation as a part of the innate response to disturbances. Several cell types participate in the synthesis and release of AA metabolites, while many cell types represent the targets for eicosanoid action. Endothelial cells (EC), forming a semi-permeable barrier between the interior space of blood vessels and underlying tissues, are of particular importance for the development of inflammation, since endothelium controls such diverse processes as vascular tone, homeostasis, adhesion of platelets and leukocytes to the vascular wall, and permeability of the vascular wall for cells and fluids. Proliferation and migration of endothelial cells contribute significantly to new vessel development (angiogenesis). This review discusses endothelial-specific synthesis and action of arachidonic acid derivatives with a particular focus on the mechanisms of signal transduction and associated intracellular protein targets.
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Affiliation(s)
- Natalia V Bogatcheva
- Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, TX 77030, USA
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21
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Newman JW, Morisseau C, Hammock BD. Epoxide hydrolases: their roles and interactions with lipid metabolism. Prog Lipid Res 2005; 44:1-51. [PMID: 15748653 DOI: 10.1016/j.plipres.2004.10.001] [Citation(s) in RCA: 320] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The epoxide hydrolases (EHs) are enzymes present in all living organisms, which transform epoxide containing lipids by the addition of water. In plants and animals, many of these lipid substrates have potent biologically activities, such as host defenses, control of development, regulation of inflammation and blood pressure. Thus the EHs have important and diverse biological roles with profound effects on the physiological state of the host organisms. Currently, seven distinct epoxide hydrolase sub-types are recognized in higher organisms. These include the plant soluble EHs, the mammalian soluble epoxide hydrolase, the hepoxilin hydrolase, leukotriene A4 hydrolase, the microsomal epoxide hydrolase, and the insect juvenile hormone epoxide hydrolase. While our understanding of these enzymes has progressed at different rates, here we discuss the current state of knowledge for each of these enzymes, along with a distillation of our current understanding of their endogenous roles. By reviewing the entire enzyme class together, both commonalities and discrepancies in our understanding are highlighted and important directions for future research pertaining to these enzymes are indicated.
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Affiliation(s)
- John W Newman
- Department of Entomology, UCDavis Cancer Center, University of California, One Shields Avenue, Davis, CA 95616, USA
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Hurley BP, Siccardi D, Mrsny RJ, McCormick BA. Polymorphonuclear Cell Transmigration Induced byPseudomonas aeruginosaRequires the Eicosanoid Hepoxilin A3. THE JOURNAL OF IMMUNOLOGY 2004; 173:5712-20. [PMID: 15494523 DOI: 10.4049/jimmunol.173.9.5712] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Lung inflammation resulting from bacterial infection of the respiratory mucosal surface in diseases such as cystic fibrosis and pneumonia contributes significantly to the pathology. A major consequence of the inflammatory response is the recruitment and accumulation of polymorphonuclear cells (PMNs) at the infection site. It is currently unclear what bacterial factors trigger this response and exactly how PMNs are directed across the epithelial barrier to the airway lumen. An in vitro model consisting of human PMNs and alveolar epithelial cells (A549) grown on inverted Transwell filters was used to determine whether bacteria are capable of inducing PMN migration across these epithelial barriers. A variety of lung pathogenic bacteria, including Klebsiella pneumoniae, Escherichia coli, and Pseudomonas aeruginosa are indeed capable of inducing PMN migration across A549 monolayers. This phenomenon is not mediated by LPS, but requires live bacteria infecting the apical surface. Bacterial interaction with the apical surface of A549 monolayers results in activation of epithelial responses, including the phosphorylation of ERK1/2 and secretion of the PMN chemokine IL-8. However, secretion of IL-8 in response to bacterial infection is neither necessary nor sufficient to mediate PMN transepithelial migration. Instead, PMN transepithelial migration is mediated by the eicosanoid hepoxilin A3, which is a PMN chemoattractant secreted by A549 cells in response to bacterial infection in a protein kinase C-dependent manner. These data suggest that bacterial-induced hepoxilin A3 secretion may represent a previously unrecognized inflammatory mechanism occurring within the lung epithelium during bacterial infections.
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Affiliation(s)
- Bryan P Hurley
- Mucosal Immunology Laboratory, Massachusetts General Hospital, Charlestown, MA 02129, USA
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Hurley BP, McCormick BA. Intestinal epithelial defense systems protect against bacterial threats. Curr Gastroenterol Rep 2004; 6:355-61. [PMID: 15341710 DOI: 10.1007/s11894-004-0050-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
Numerous bacterial species inhabit the lumen of the human intestine. The epithelial cells that line the intestinal barrier are in direct contact with many of these species and have developed sophisticated strategies to prevent bacterial invasion of host tissue beyond simply providing a physical blockade. Intestinal epithelial cells (IECs) possess receptors that are capable of recognizing bacterial products, and engagement of these receptors results in the production and secretion of immunoregulatory proteins, such as cytokines and chemokines, which mobilize immune effector cells, including macrophages, dendritic cells, and neutrophils. In addition, IECs can produce various lipid-based eicosanoids that can contribute to the orchestration of the immune response. A better understanding of how the intestinal epithelium interacts with its microbial constituents may provide insight into strategies for treatment of enteric infections and inflammatory bowel disease.
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Affiliation(s)
- Bryan P Hurley
- Mucosal Immunology Laboratory, Massachusetts General Hospital, CNY, 114 16th Street (114-3503), Charlestown, MA 02129, USA
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24
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Shankaranarayanan P, Ciccoli R, Nigam S. Biosynthesis of hepoxilins: evidence for the presence of a hepoxilin synthase activity in rat insulinoma cells. FEBS Lett 2003; 538:107-12. [PMID: 12633862 DOI: 10.1016/s0014-5793(03)00151-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The 12(S)-lipoxygenase (12-LOX) pathway of arachidonic acid (AA) metabolism after dioxygenation to 12(S)-hydroperoxy-eicosatetraenoic acid is bifurcated in a reduction route to formation of 12(S)-hydroxy-eicosatetraenoic acid (12-HpETE) and an isomerization route to formation of hepoxilins. Interestingly, we found that the rat insulinoma RINm5F cells, which are devoid of cytoplasmic glutathione peroxidase (cGPx)/phospholipid hydroperoxide glutathione peroxidase (PHGPx), produce solely hepoxilin A(3) (HXA(3)). Since HXA(3) synthesis was abolished in heat-denatured or cGPx- or PHGPx-transfected cells, it was tempting to speculate that a HXA(3) synthase activity regulated by cGPx/PHGPx is present. To confirm this assumption we incubated AA with HeLa cells overexpressing the rat leukocyte-type 12-LOX. Neither HXA(3) nor 12(S)-HETE were detected due to abundance of cGPx/PHGPx. But, pretreatment of transfected cells with diethyl maleate, an inhibitor of glutathione and PHGPx, restored HXA(3) synthase and 12-LOX activities. Thus, we conclude, that cells containing rat leukocyte-type 12-LOX also possess an intrinsic HXA(3) synthase activity, which is activated by inhibition of cGPx/PHGPx. In normal cells HXA(3) is down-regulated by cGPx/PHGPx, but, it is persistently activated in oxidatively stressed cells deficient in cGPx/PHGPx, such as RINm5F.
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Affiliation(s)
- Pattabhiraman Shankaranarayanan
- Eicosanoid Research Division and Centre for Experimental Gynecology and Breast Research, University Medical Centre Benjamin Franklin, Free University Berlin, Hindenburgdamm 30, D-12200 Berlin, Germany
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25
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Jankov RP, Luo X, Demin P, Aslam R, Hannam V, Tanswell AK, Pace-Asciak CR. Hepoxilin analogs inhibit bleomycin-induced pulmonary fibrosis in the mouse. J Pharmacol Exp Ther 2002; 301:435-40. [PMID: 11961041 DOI: 10.1124/jpet.301.2.435] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Bleomycin has been suggested to incite plasma extravasation and influx of inflammatory cells leading to pulmonary fibrosis. We hypothesized that stable analogs of the 12-lipoxygenase product, hepoxilin, may attenuate these effects. We initially investigated the effects of the four hepoxilin analogs (PBT-1 to -4) coadministered intradermally with bleomycin and found that PBT-1 and -2 significantly opposed the vascular permeability effects of bleomycin in rat skin. We subsequently tested the hepoxilin analogs for their actions in opposing the intratracheal bleomycin-evoked acute inflammatory phase of lung fibrosis in the mouse, characterized by a marked accumulation of macrophages and an increase in the rate of collagen synthesis and deposition. We found that the bleomycin-evoked effects on macrophage influx were inhibited by all the hepoxilin analogs (PBT-1, -3, and -4 > PBT-2) administered i.p. for 8 days. Increased total lung collagen was completely abrogated by PBT-1 and -2, whereas PBT-3 and -4 had little effect. A dose-response study with PBT-1 indicated that the effective dose for inhibition of bleomycin-induced inflammatory and histological changes was below 10 microg/day. These studies demonstrate an in vivo action of stable analogs of hepoxilin and support an effect on inflammation and vascular permeability from these novel compounds, especially for PBT-1.
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Affiliation(s)
- Robert P Jankov
- Programmes in Lung Biology, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada
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