1
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Azizpor P, Okakpu OK, Parks SC, Chavez D, Eyabi F, Martinez-Beltran S, Nguyen S, Dillman AR. Polyunsaturated fatty acids stimulate immunity and eicosanoid production in Drosophila melanogaster. J Lipid Res 2024; 65:100608. [PMID: 39069231 PMCID: PMC11386307 DOI: 10.1016/j.jlr.2024.100608] [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: 06/15/2023] [Revised: 07/19/2024] [Accepted: 07/22/2024] [Indexed: 07/30/2024] Open
Abstract
Eicosanoids are a class of molecules derived from C20 polyunsaturated fatty acids (PUFAs) that play a vital role in mammalian and insect biological systems, including development, reproduction, and immunity. Recent research has shown that insects have significant but lower levels of C20 PUFAs in circulation in comparison to C18 PUFAs. It has been previously hypothesized in insects that eicosanoids are synthesized from C18 precursors, such as linoleic acid (LA), to produce downstream eicosanoids. In this study, we show that introduction of arachidonic acid (AA) stimulates production of cyclooxygenase, lipoxygenase, and cytochrome P450-derived eicosanoids. Downstream immune readouts showed that LA stimulates phagocytosis by hemocytes, while both LA and AA stimulate increased antimicrobial peptide production when D. melanogaster is exposed to a heat-killed bacterial pathogen. In totality, this work identifies PUFAs that are involved in insect immunity and adds evidence to the notion that Drosophila utilizes immunostimulatory lipid signaling to mitigate bacterial infections. Our understanding of immune signaling in the fly and its analogies to mammalian systems will increase the power and value of Drosophila as a model organism in immune studies.
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Affiliation(s)
- Pakeeza Azizpor
- Department of Nematology, University of California, Riverside, CA, USA
| | - Ogadinma K Okakpu
- Department of Nematology, University of California, Riverside, CA, USA
| | - Sophia C Parks
- Department of Nematology, University of California, Riverside, CA, USA
| | - Diego Chavez
- Department of Nematology, University of California, Riverside, CA, USA
| | - Fayez Eyabi
- Department of Nematology, University of California, Riverside, CA, USA
| | | | - Susan Nguyen
- Department of Nematology, University of California, Riverside, CA, USA
| | - Adler R Dillman
- Department of Nematology, University of California, Riverside, CA, USA.
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2
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Rahman MS, Hossain MS. Eicosanoids Signals in SARS-CoV-2 Infection: A Foe or Friend. Mol Biotechnol 2023:10.1007/s12033-023-00919-4. [PMID: 37878227 DOI: 10.1007/s12033-023-00919-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Accepted: 09/25/2023] [Indexed: 10/26/2023]
Abstract
SARS-CoV-2 mediated infection instigated a scary pandemic state since 2019. They created havoc comprising death, imbalanced social structures, and a wrecked global economy. During infection, the inflammation and associated cytokine storm generate a critical pathological situation in the human body, especially in the lungs. By the passage of time of infection, inflammatory disorders, and multiple organ damage happen which might lead to death, if not treated properly. Until now, many pathological parameters have been used to understand the progress of the severity of COVID-19 but with limited success. Bioactive lipid mediators have the potential of initiating and resolving inflammation in any disease. The connection between lipid storm and inflammatory states of SARS-CoV-2 infection has surfaced and got importance to understand and mitigate the pathological states of COVID-19. As the role of eicosanoids in COVID-19 infection is not well defined, available information regarding this issue has been accumulated to address the possible network of eicosanoids related to the initiation of inflammation, promotion of cytokine storm, and resolution of inflammation, and highlight possible strategies for treatment and drug discovery related to SARS-CoV-2 infection in this study. Understanding the involvement of eicosanoids in exploration of cellular events provoked by SARS-CoV-2 infection has been summarized as an important factor to deescalate any upcoming catastrophe imposed by the lethal variants of this micro-monster. Additionally, this study also recognized the eicosanoid based drug discovery, treatment, and strategies for managing the severity of SARS-COV-2 infection.
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Affiliation(s)
- Mohammad Sharifur Rahman
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Dhaka, Dhaka, 1000, Bangladesh.
| | - Mohammad Salim Hossain
- Department of Pharmacy, Noakhali Science and Technology University, Noakhali, 3814, Bangladesh.
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3
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Anand S, Azam Ansari M, Kumaraswamy Sukrutha S, Alomary MN, Anwar Khan A, Elderdery AY. Resolvins Lipid Mediators: Potential Therapeutic Targets in Alzheimer and Parkinson Disease. Neuroscience 2022; 507:139-148. [PMID: 36372297 DOI: 10.1016/j.neuroscience.2022.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 10/12/2022] [Accepted: 11/04/2022] [Indexed: 11/13/2022]
Abstract
Inflammation and resolution are highly programmed processes involving a plethora of immune cells. Lipid mediators synthesized from arachidonic acid metabolism play a pivotal role in orchestrating the signaling cascades in the game of inflammation. The majority of the studies carried out so far on inflammation were aimed at inhibiting the generation of inflammatory molecules, whereas recent research has shifted more towards understanding the resolution of inflammation. Owing to chronic inflammation as evident in neuropathophysiology, the resolution of inflammation together with the class of lipid mediators actively involved in its regulation has attracted the attention of the scientific community as therapeutic targets. Both omega-three polyunsaturated fatty acids, eicosapentaenoic acid and docosahexaenoic acid, orchestrate a vital regulatory role in inflammation development. Resolvins derived from these fatty acids comprise the D-and E-series resolvins. A growing body of evidence using in vitro and in vivo models has revealed the pro-resolving and anti-inflammatory potential of resolvins. This systematic review sheds light on the synthesis, specialized receptors, and resolution of inflammation mediated by resolvins in Alzheimer's and Parkinson's disease.
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Affiliation(s)
- Santosh Anand
- Department of Biotechnology, School of Applied Sciences, REVA University, Bengaluru, Karnataka, India
| | - Mohammad Azam Ansari
- Department of Epidemic Disease Research, Institutes for Research and Medical Consultations, Imam Abdulrahman Bin Faisal University, Dammam 31441, Saudi Arabia.
| | - Sambamurthy Kumaraswamy Sukrutha
- Department of Microbiology, Biotechnology and Food Technology, Jnana Bharathi Campus, Bangalore University, Bengaluru, Karnataka, India
| | - Mohammad N Alomary
- National Centre for Biotechnology, King Abdulaziz City for Science and Technology (KACST), Riyadh 11442, Saudi Arabia
| | - Anmar Anwar Khan
- Laboratory Medicine Department, Faculty of Applied Medical Sciences, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Abozer Y Elderdery
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Jouf University, Saudi Arabia
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4
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Gallegos EM, Reed TD, Mathes FA, Guevara NV, Neau DB, Huang W, Newcomer ME, Gilbert NC. Helical remodeling augments 5-lipoxygenase activity in the synthesis of pro-inflammatory mediators. J Biol Chem 2022; 298:102282. [PMID: 35863431 PMCID: PMC9418500 DOI: 10.1016/j.jbc.2022.102282] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 07/13/2022] [Accepted: 07/15/2022] [Indexed: 11/29/2022] Open
Abstract
The synthesis of pro-inflammatory leukotrienes implicated in asthma, allergic rhinitis, and atherosclerosis is initiated by the enzyme 5-lipoxygenase (5-LOX). The crystal structure of human Stable-5-LOX revealed a conformation where the catalytic iron was inaccessible to bulk solvent as two aromatic residues on a conserved helix-α2 (Hα2) plugged the substrate access portal. Whether 5-LOX can also adopt a more open conformation has not been resolved. Here, we present a new conformation of 5-LOX where Hα2 adopts an elongated conformation equivalent to that described in other animal lipoxygenase structures. Our observation of the sigmoidal kinetic behavior of 5-LOX, which is indicative of positive cooperativity, is consistent with a substrate-induced conformational change that shifts the ensemble of enzyme populations to favor the catalytically competent state. Strategic point mutations along Hα2 designed to unlock the closed conformation and elongate Hα2 resulted in improved kinetic parameters, altered limited-proteolysis data, and a drastic reduction in the length of the lag phase yielding the most active Stable-5-LOX to date. Structural predictions by AlphaFold2 of these variants statistically favor an elongated Hα2 and reinforce a model in which improved kinetic parameters correlate with a more readily adopted, open conformation. Taken together, these data provide valuable insights into the synthesis of leukotrienes.
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Affiliation(s)
- Eden M Gallegos
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, USA
| | - Tanner D Reed
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, USA
| | - Forge A Mathes
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, USA
| | - Nelson V Guevara
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, USA
| | - David B Neau
- Cornell University, Northeastern Collaborative Access Team, Argonne National Laboratory, Argonne, IL, USA
| | - Wei Huang
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH, USA
| | - Marcia E Newcomer
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, USA
| | - Nathaniel C Gilbert
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, USA.
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5
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He Z, Wang DW. The roles of eicosanoids in myocardial diseases. ADVANCES IN PHARMACOLOGY 2022; 97:167-200. [DOI: 10.1016/bs.apha.2022.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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6
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Gilbert NC, Newcomer ME, Werz O. Untangling the web of 5-lipoxygenase-derived products from a molecular and structural perspective: The battle between pro- and anti-inflammatory lipid mediators. Biochem Pharmacol 2021; 193:114759. [PMID: 34487716 PMCID: PMC8865081 DOI: 10.1016/j.bcp.2021.114759] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 08/29/2021] [Accepted: 09/01/2021] [Indexed: 12/31/2022]
Abstract
Arachidonic acid (AA) is the precursor to leukotrienes (LT), potent mediators of the inflammatory response. In the 35 + years since cysteinyl-LTs were reported to mediate antigen-induced constriction of bronchi in tissue from asthma patients, numerous cellular responses evoked by the LTs, such as chemoattraction and G protein-coupled receptor (GPCR) activation, have been elucidated and revealed a potential for 5-lipoxygenase (5-LOX) as a promising drug target that goes beyond asthma. We describe herein early work identifying 5-LOX as the key enzyme that initiates LT biosynthesis and the discovery of its membrane-embedded helper protein required to execute the two-step reaction that transforms AA to the progenitor leukotriene A4 (LTA4). 5-LOX must traffic to the nuclear membrane to interact with its partner and undergo a conformational change so that AA can enter the active site. Additionally, the enzyme must retain the hydroperoxy-reaction intermediate for its final transformation to LTA4. Each of these steps provide a unique target for inhibition. Next, we describe the recent structures of GPCRs that recognize metabolites of the 5-LOX pathway and thus provide target alternatives. We also highlight the role of 5-LOX in the biosynthesis of anti-inflammatory lipid mediators (LM), the so-called specialized pro-resolving mediators (SPM). The involvement of 5-LOX in the biosynthesis of LM with opposing functions undoubtedly complicates the continuing search for 5-LOX inhibitors as therapeutic leads. Finally, we address the recent discovery of how some allosteric 5-LOX inhibitors promote oxygenation at the 12/15 carbon on AA to generate mediators that resolve, rather than promote, inflammation.
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Affiliation(s)
- Nathaniel C Gilbert
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, USA.
| | - Marcia E Newcomer
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, USA
| | - Oliver Werz
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, 07743 Jena, Germany
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7
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Sehanobish E, Asad M, Barbi M, Porcelli SA, Jerschow E. Aspirin Actions in Treatment of NSAID-Exacerbated Respiratory Disease. Front Immunol 2021; 12:695815. [PMID: 34305932 PMCID: PMC8297972 DOI: 10.3389/fimmu.2021.695815] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 06/07/2021] [Indexed: 12/21/2022] Open
Abstract
Non-steroidal Anti-inflammatory drugs (NSAID)-exacerbated respiratory disease (N-ERD) is characterized by nasal polyposis, chronic rhinosinusitis, adult-onset asthma and hypersensitive reactions to cyclooxygenase-1 (COX-1) inhibitors. Among the available treatments for this disease, a combination of endoscopic sinus surgery followed by aspirin desensitization and aspirin maintenance therapy has been an effective approach. Studies have shown that long-term aspirin maintenance therapy can reduce the rate of nasal polyp recurrence in patients with N-ERD. However, the exact mechanism by which aspirin can both trigger and suppress airway disease in N-ERD remains poorly understood. In this review, we summarize current knowledge of aspirin effects in N-ERD, cardiovascular disease, and cancer, and consider potential mechanistic pathways accounting for the effects of aspirin in N-ERD.
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Affiliation(s)
- Esha Sehanobish
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, United States
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Mohammad Asad
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, United States
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Mali Barbi
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Steven A. Porcelli
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, United States
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Elina Jerschow
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, United States
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States
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8
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Wang B, Wu L, Chen J, Dong L, Chen C, Wen Z, Hu J, Fleming I, Wang DW. Metabolism pathways of arachidonic acids: mechanisms and potential therapeutic targets. Signal Transduct Target Ther 2021; 6:94. [PMID: 33637672 PMCID: PMC7910446 DOI: 10.1038/s41392-020-00443-w] [Citation(s) in RCA: 425] [Impact Index Per Article: 141.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 10/04/2020] [Accepted: 10/15/2020] [Indexed: 01/31/2023] Open
Abstract
The arachidonic acid (AA) pathway plays a key role in cardiovascular biology, carcinogenesis, and many inflammatory diseases, such as asthma, arthritis, etc. Esterified AA on the inner surface of the cell membrane is hydrolyzed to its free form by phospholipase A2 (PLA2), which is in turn further metabolized by cyclooxygenases (COXs) and lipoxygenases (LOXs) and cytochrome P450 (CYP) enzymes to a spectrum of bioactive mediators that includes prostanoids, leukotrienes (LTs), epoxyeicosatrienoic acids (EETs), dihydroxyeicosatetraenoic acid (diHETEs), eicosatetraenoic acids (ETEs), and lipoxins (LXs). Many of the latter mediators are considered to be novel preventive and therapeutic targets for cardiovascular diseases (CVD), cancers, and inflammatory diseases. This review sets out to summarize the physiological and pathophysiological importance of the AA metabolizing pathways and outline the molecular mechanisms underlying the actions of AA related to its three main metabolic pathways in CVD and cancer progression will provide valuable insight for developing new therapeutic drugs for CVD and anti-cancer agents such as inhibitors of EETs or 2J2. Thus, we herein present a synopsis of AA metabolism in human health, cardiovascular and cancer biology, and the signaling pathways involved in these processes. To explore the role of the AA metabolism and potential therapies, we also introduce the current newly clinical studies targeting AA metabolisms in the different disease conditions.
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Affiliation(s)
- Bei Wang
- Division of Cardiology, Department of Internal Medicine and Gene Therapy Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Huazhong University of Science and Technology, Hubei Province, Wuhan, China
- Department of Rheumatology and Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Hubei, Wuhan, China
| | - Lujin Wu
- Division of Cardiology, Department of Internal Medicine and Gene Therapy Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Huazhong University of Science and Technology, Hubei Province, Wuhan, China
| | - Jing Chen
- Division of Cardiology, Department of Internal Medicine and Gene Therapy Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Huazhong University of Science and Technology, Hubei Province, Wuhan, China
| | - Lingli Dong
- Department of Rheumatology and Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Hubei, Wuhan, China
| | - Chen Chen
- Division of Cardiology, Department of Internal Medicine and Gene Therapy Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Huazhong University of Science and Technology, Hubei Province, Wuhan, China
| | - Zheng Wen
- Division of Cardiology, Department of Internal Medicine and Gene Therapy Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Huazhong University of Science and Technology, Hubei Province, Wuhan, China
| | - Jiong Hu
- Institute for Vascular Signalling, Centre for Molecular Medicine, Goethe University, Frankfurt am Main, Germany
| | - Ingrid Fleming
- Institute for Vascular Signalling, Centre for Molecular Medicine, Goethe University, Frankfurt am Main, Germany
| | - Dao Wen Wang
- Division of Cardiology, Department of Internal Medicine and Gene Therapy Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
- Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Huazhong University of Science and Technology, Hubei Province, Wuhan, China.
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9
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Biringer RG. The enzymology of human eicosanoid pathways: the lipoxygenase branches. Mol Biol Rep 2020; 47:7189-7207. [PMID: 32748021 DOI: 10.1007/s11033-020-05698-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 07/26/2020] [Indexed: 12/16/2022]
Abstract
Eicosanoids are short-lived derivatives of polyunsaturated fatty acids that serve as autocrine and paracrine signaling molecules. They are involved numerous biological processes of both the well state and disease states. A thorough understanding of the progression the disease state and homeostasis of the well state requires a complete evaluation of the systems involved. This review examines the enzymology for the enzymes involved in the production of eicosanoids along the lipoxygenase branches of the eicosanoid pathways with particular emphasis on those derived from arachidonic acid. The enzymatic parameters, protocols to measure them, and proposed catalytic mechanisms are presented in detail.
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Affiliation(s)
- Roger Gregory Biringer
- College of Osteopathic Medicine, Lake Erie College of Osteopathic Medicine, Bradenton, FL, 34211, USA.
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10
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Gilbert NC, Gerstmeier J, Schexnaydre EE, Börner F, Garscha U, Neau DB, Werz O, Newcomer ME. Structural and mechanistic insights into 5-lipoxygenase inhibition by natural products. Nat Chem Biol 2020; 16:783-790. [PMID: 32393899 DOI: 10.1038/s41589-020-0544-7] [Citation(s) in RCA: 122] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 04/06/2020] [Indexed: 12/31/2022]
Abstract
Leukotrienes (LT) are lipid mediators of the inflammatory response that are linked to asthma and atherosclerosis. LT biosynthesis is initiated by 5-lipoxygenase (5-LOX) with the assistance of the substrate-binding 5-LOX-activating protein at the nuclear membrane. Here, we contrast the structural and functional consequences of the binding of two natural product inhibitors of 5-LOX. The redox-type inhibitor nordihydroguaiaretic acid (NDGA) is lodged in the 5-LOX active site, now fully exposed by disordering of the helix that caps it in the apo-enzyme. In contrast, the allosteric inhibitor 3-acetyl-11-keto-beta-boswellic acid (AKBA) from frankincense wedges between the membrane-binding and catalytic domains of 5-LOX, some 30 Å from the catalytic iron. While enzyme inhibition by NDGA is robust, AKBA promotes a shift in the regiospecificity, evident in human embryonic kidney 293 cells and in primary immune cells expressing 5-LOX. Our results suggest a new approach to isoform-specific 5-LOX inhibitor development through exploitation of an allosteric site in 5-LOX.
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Affiliation(s)
- Nathaniel C Gilbert
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, USA
| | - Jana Gerstmeier
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University, Jena, Germany
| | - Erin E Schexnaydre
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, USA
| | - Friedemann Börner
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University, Jena, Germany
| | - Ulrike Garscha
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University, Jena, Germany
| | - David B Neau
- Cornell University, Northeastern Collaborative Access Team, Argonne National Laboratory, Argonne, IL, USA
| | - Oliver Werz
- Department of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University, Jena, Germany.
| | - Marcia E Newcomer
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, USA.
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11
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Toda K, Tsukayama I, Nagasaki Y, Konoike Y, Tamenobu A, Ganeko N, Ito H, Kawakami Y, Takahashi Y, Miki Y, Yamamoto K, Murakami M, Suzuki-Yamamoto T. Red-kerneled rice proanthocyanidin inhibits arachidonate 5-lipoxygenase and decreases psoriasis-like skin inflammation. Arch Biochem Biophys 2020; 689:108307. [PMID: 32112739 DOI: 10.1016/j.abb.2020.108307] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Revised: 02/14/2020] [Accepted: 02/18/2020] [Indexed: 12/13/2022]
Abstract
5-lipoxygenase is a key enzyme in the synthesis of leukotrienes from arachidonic acid. The produced leukotrienes are involved in inflammatory diseases including psoriasis, asthma, and atherosclerosis. A suitable 5-lipoxygenase inhibitor might be useful for preventing and improving the symptoms of leukotriene-related inflammatory diseases. Here, we investigate the mechanism underlying the anti-inflammatory effect of a proanthocyanidin found in red-kerneled rice. Red-kerneled rice proanthocyanidin exhibited potent mixed noncompetitive inhibition of human and rat 5-lipoxygenases, with an IC50 values of 15.1 μM against human enzyme, and 7.0 μM against rat enzyme, respectively. This compound decreased leukotriene B4 production in rat basophilic leukemia-2H3 cells. In imiquimod-induced psoriasis-like mouse skin, topical application of the proanthocyanidin suppressed hyperplasia, decreased inflammatory cell infiltration, and down-regulated expression of the psoriasis-associated genes Il17a, Il22, S100a9, and Krt1. Lipid metabolome analysis by electrospray ionization mass spectrometry showed that red-kerneled rice proanthocyanidin treatment of psoriasis-like mouse skin dose-dependently decreased the production of leukotriene B4 but no other arachidonate metabolites. Red-kerneled rice proanthocyanidin inhibits 5-lipoxygenase, resulting in a decrease in leukotriene B4 production and psoriasis-like mouse skin inflammation. These results suggest that this proanthocyanidin may be therapeutically effective for treating leukotriene-related diseases.
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Affiliation(s)
- Keisuke Toda
- Department of Nutritional Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama, 719-1197, Japan
| | - Izumi Tsukayama
- Department of Nutritional Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama, 719-1197, Japan
| | - Yuki Nagasaki
- Department of Nutritional Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama, 719-1197, Japan
| | - Yuka Konoike
- Department of Nutritional Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama, 719-1197, Japan; Department of Nutrition and Life Science, Fukuyama University, Sanzo, Gakuen-cho 1, Fukuyama, Hiroshima, 729-0292, Japan
| | - Asako Tamenobu
- Department of Nutritional Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama, 719-1197, Japan
| | - Natsuki Ganeko
- Department of Nutritional Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama, 719-1197, Japan
| | - Hideyuki Ito
- Department of Nutritional Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama, 719-1197, Japan
| | - Yuki Kawakami
- Department of Nutritional Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama, 719-1197, Japan
| | - Yoshitaka Takahashi
- Department of Nutritional Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama, 719-1197, Japan
| | - Yoshimi Miki
- Laboratory of Microenvironmental and Metabolic Health Sciences, Center for Disease Biology and Integrative Medicine, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan
| | - Kei Yamamoto
- Graduate School of Technology, Industrial and Social Science, Tokushima University, 2-1, Minami-jyosanjima-cho, Tokushima, 770-8513, Japan
| | - Makoto Murakami
- Laboratory of Microenvironmental and Metabolic Health Sciences, Center for Disease Biology and Integrative Medicine, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan
| | - Toshiko Suzuki-Yamamoto
- Department of Nutritional Science, Okayama Prefectural University, 111 Kuboki, Soja, Okayama, 719-1197, Japan.
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12
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Hajeyah AA, Griffiths WJ, Wang Y, Finch AJ, O’Donnell VB. The Biosynthesis of Enzymatically Oxidized Lipids. Front Endocrinol (Lausanne) 2020; 11:591819. [PMID: 33329396 PMCID: PMC7711093 DOI: 10.3389/fendo.2020.591819] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 10/26/2020] [Indexed: 12/14/2022] Open
Abstract
Enzymatically oxidized lipids are a specific group of biomolecules that function as key signaling mediators and hormones, regulating various cellular and physiological processes from metabolism and cell death to inflammation and the immune response. They are broadly categorized as either polyunsaturated fatty acid (PUFA) containing (free acid oxygenated PUFA "oxylipins", endocannabinoids, oxidized phospholipids) or cholesterol derivatives (oxysterols, steroid hormones, and bile acids). Their biosynthesis is accomplished by families of enzymes that include lipoxygenases (LOX), cyclooxygenases (COX), cytochrome P450s (CYP), and aldo-keto reductases (AKR). In contrast, non-enzymatically oxidized lipids are produced by uncontrolled oxidation and are broadly considered to be harmful. Here, we provide an overview of the biochemistry and enzymology of LOXs, COXs, CYPs, and AKRs in humans. Next, we present biosynthetic pathways for oxylipins, oxidized phospholipids, oxysterols, bile acids and steroid hormones. Last, we address gaps in knowledge and suggest directions for future work.
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Affiliation(s)
- Ali A. Hajeyah
- Systems Immunity Research Institute and Division of Infection and Immunity, Cardiff University, Cardiff, United Kingdom
- *Correspondence: Ali A. Hajeyah,
| | - William J. Griffiths
- Institute of Life Science, Swansea University Medical School, Swansea, United Kingdom
| | - Yuqin Wang
- Institute of Life Science, Swansea University Medical School, Swansea, United Kingdom
| | - Andrew J. Finch
- Centre for Tumour Biology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Valerie B. O’Donnell
- Systems Immunity Research Institute and Division of Infection and Immunity, Cardiff University, Cardiff, United Kingdom
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Häfner AK, Kahnt AS, Steinhilber D. Beyond leukotriene formation—The noncanonical functions of 5-lipoxygenase. Prostaglandins Other Lipid Mediat 2019; 142:24-32. [DOI: 10.1016/j.prostaglandins.2019.03.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 03/14/2019] [Accepted: 03/25/2019] [Indexed: 01/17/2023]
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14
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Jonasdottir HS, Brouwers H, Toes REM, Ioan-Facsinay A, Giera M. Effects of anticoagulants and storage conditions on clinical oxylipid levels in human plasma. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1863:1511-1522. [PMID: 30308322 DOI: 10.1016/j.bbalip.2018.10.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 09/30/2018] [Accepted: 10/05/2018] [Indexed: 01/16/2023]
Abstract
Metabolomics and lipidomics are of fundamental importance to personalized healthcare. Particularly the analysis of bioactive lipids is of relevance to a better understanding of various diseases. Within clinical routines, blood derived samples are widely used for diagnostic and research purposes. Hence, standardized and validated procedures for blood collection and storage are mandatory, in order to guarantee sample integrity and relevant study outcomes. We here investigated different plasma storage conditions and their effect on plasma fatty acid and oxylipid levels. Our data clearly indicate the importance of storage conditions for plasma lipidomic analysis. Storage at very low temperature (-80 °C) and the addition of methanol directly after sampling are the most important measures to avoid ex vivo synthesis of oxylipids. Furthermore, we identified critical analytes being affected under certain storage conditions. Finally, we carried out chiral analysis and found possible residual enzymatic activity to be one of the contributors to the ex vivo formation of oxylipids even at -20 °C.
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Affiliation(s)
- Hulda S Jonasdottir
- Leiden University Medical Center, Center for Proteomics and Metabolomics, Albinusdreef 2, 2300RC Leiden, the Netherlands; Leiden University Medical Center, Department of Rheumatology, Albinusdreef 2, 2300RC Leiden, the Netherlands
| | - Hilde Brouwers
- Leiden University Medical Center, Department of Rheumatology, Albinusdreef 2, 2300RC Leiden, the Netherlands
| | - René E M Toes
- Leiden University Medical Center, Department of Rheumatology, Albinusdreef 2, 2300RC Leiden, the Netherlands
| | - Andreea Ioan-Facsinay
- Leiden University Medical Center, Department of Rheumatology, Albinusdreef 2, 2300RC Leiden, the Netherlands
| | - Martin Giera
- Leiden University Medical Center, Center for Proteomics and Metabolomics, Albinusdreef 2, 2300RC Leiden, the Netherlands.
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Abstract
The stereoselective synthesis of resolvin D4 (RvD4) was achieved using the Wittig reaction of the C1-C10 dienal with the known C11-C22 phosphonium salt. The ( S, E)-enantiomer ( S)-10, corresponding to the C1-C8 part, was synthesized in 95% ee by the asymmetric transfer hydrogenation reaction of the corresponding acetylenic ketone followed by Red-Al reduction. Sharpless epoxidation of this alcohol using Ti(O- i-Pr)4/l-(+)-DIPT as a catalyst produced anti epoxy alcohol with >99% ee as the sole product in 82% yield. A subsequent functional group manipulation, including removal of the PMB group, produced the alcohol, which upon Swern oxidation afforded anti 4-hydroxy-5-TBS-oxy enal via epoxide ring opening of the resulting aldehyde. The Horner-Wadsworth-Emmons reaction was used to add the C9-C10 enal part to this aldehyde, and the resulting dienal was subjected to the Wittig reaction with C11-C22 phosphonium salt to furnish the entire structure of RvD4. Conversion of the primary alcohol to the methyl ester and deprotection of the three TBS groups with TBAF afforded 5,17-dihydroxy-γ-lactone, which was hydrolyzed to RvD4. Additionally, anti-4,5-dihydroxydodecanoic acid, a model compound of RvD4, in CD3OD was observed to be stable at room temperature for several weeks, whereas 20% of the acid in CDCl3 was converted into the γ-lactone after 24 h at rt.
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Affiliation(s)
- Masao Morita
- Department of Bioengineering , Tokyo Institute of Technology , Box B-52, Nagatsuta-cho 4259 , Midori-ku, Yokohama 226-8501 , Japan
| | - Yuichi Kobayashi
- Department of Bioengineering , Tokyo Institute of Technology , Box B-52, Nagatsuta-cho 4259 , Midori-ku, Yokohama 226-8501 , Japan
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16
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A new method to evaluate anti-allergic effect of food component by measuring leukotriene B 4 from a mouse mast cell line. Cytotechnology 2017; 70:177-184. [PMID: 28852902 DOI: 10.1007/s10616-017-0129-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 07/25/2017] [Indexed: 02/03/2023] Open
Abstract
Leukotrienes (LTs), chemical mediators produced by mast cells, play an important role in allergic symptoms such as food allergies and hay fever. We tried to construct an evaluation method for the anti-LTB4 activity of chemical substances using a mast cell line, PB-3c. PB-3c pre-cultured with or without arachidonic acid (AA) was stimulated by calcium ionophore (A23187) for 20 min, and LTB4 production by the cells was determined by HPLC with UV detection. LTB4 was not detected when PB-3c was pre-cultured without AA. On the other hand, LTB4 production by PB-3c pre-cultured with AA was detectable by HPLC, and the optimal conditions of PB-3c for LTB4 detection were to utilize the cells pre-cultured with 50 µM AA for 48 h. MK-886 (5-lipoxygenase inhibitor) completely inhibited LTB4 production, but AACOCF3 (phospholipase A2 inhibitor) slightly increased LTB4 production, suggesting that LTB4 was generated from exogenous free AA through 5-lipoxygenase pathway. We applied this technique to the evaluation of the anti-LTB4 activity of food components. PB-3c pre-cultured with 50 µM AA for 48 h was stimulated with A23187 in the presence of 50 µM soybean isoflavones (daidzin, genistin, daidzein, and genistein), equol, quercetin, or kaempferol. Genistein, equol, quercetin, and kaempferol strongly inhibited LTB4 production without cytotoxicity. These results suggest that a new assay system using PB-3c is convenient to evaluate LTB4 inhibition activity by food components. This method could be utilized for elucidation of the mechanisms of LTB4 release suppression by food components such as flavonoids and the structure-activity relationship.
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17
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Madeira MFM, Queiroz-Junior CM, Corrêa JD, Werneck SMC, Machado FS, Cunha TM, Garlet GP, Teixeira MM, Silva TA, Souza DG. The role of 5-lipoxygenase in Aggregatibacter actinomycetemcomitans-induced alveolar bone loss. J Clin Periodontol 2017; 44:793-802. [PMID: 28569991 DOI: 10.1111/jcpe.12755] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/28/2017] [Indexed: 11/27/2022]
Abstract
AIM Leukotrienes (LTs) are pro-inflammatory lipid mediators formed by the enzyme 5-lipoxygenase (5-LO). The involvement of 5-LO metabolites in periodontal disease (PD) is not well defined. This study aimed to assess the role of 5-LO in experimental PD induced by Aggregatibacter actinomycetemcomitans (Aa). MATERIAL AND METHODS In vivo experiments were carried out using SV129 wild-type (WT) and 5-LO-deficient (5lo-/- ) mice inoculated with Aa. Osteoclasts were stimulated in vitro with AaLPS in the presence or not of selective inhibitors of the 5-LO pathway, or LTB4 or platelet-activating factor (PAF), as PAF has already been shown to increase osteoclast activity. RESULTS In 5lo-/- mice, there were no loss of alveolar bone and less TRAP-positive osteoclasts in periodontal tissues, after Aa inoculation, despite local production of TNF-α and IL-6. The differentiation and activity of osteoclasts stimulated with AaLPS were diminished in the presence of BLT1 antagonist or 5-LO inhibitor, but not in the presence of cysteinyl leukotriene receptor antagonist. The osteoclast differentiation induced by PAF was impaired by the BLT1 antagonism. CONCLUSION In conclusion, LTB4 but not CysLTs is important for Aa-induced alveolar bone loss. Overall, LTB4 affects osteoclast differentiation and activity and is a key intermediate of PAF-induced osteoclastogenesis.
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Affiliation(s)
- Mila F M Madeira
- Department of Microbiology, Biological Sciences Institute, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Celso M Queiroz-Junior
- Department of Morphology, Biological Sciences Institute, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Jôice D Corrêa
- Department of Oral Pathology and Surgery, Faculty of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Sílvia M C Werneck
- Department of Microbiology, Biological Sciences Institute, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Fabiana S Machado
- Department of Biochemistry and Immunology, Biological Sciences Institute, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Thiago M Cunha
- Department of Pharmacology, Faculty of Medicine of Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil
| | - Gustavo P Garlet
- Department of Biological Sciences, School of Dentistry of Bauru, Universidade de São Paulo, Bauru, São Paulo, Brazil
| | - Mauro M Teixeira
- Department of Biochemistry and Immunology, Biological Sciences Institute, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Tarcília A Silva
- Department of Oral Pathology and Surgery, Faculty of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Daniele G Souza
- Department of Microbiology, Biological Sciences Institute, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
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18
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Ball AK, Beilstein K, Wittmann S, Sürün D, Saul MJ, Schnütgen F, Flamand N, Capelo R, Kahnt AS, Frey H, Schaefer L, Marschalek R, Häfner AK, Steinhilber D. Characterization and cellular localization of human 5-lipoxygenase and its protein isoforms 5-LOΔ13, 5-LOΔ4 and 5-LOp12. Biochim Biophys Acta Mol Cell Biol Lipids 2017; 1862:561-571. [PMID: 28257804 DOI: 10.1016/j.bbalip.2017.02.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 02/06/2017] [Accepted: 02/24/2017] [Indexed: 01/29/2023]
Abstract
Human 5-lipoxygenase (5-LO-WT) initiates the leukotriene (LT) biosynthesis. LTs play an important role in diseases like asthma, atherosclerosis and in many types of cancer. In this study, we investigated the 5-LO isoforms 5-LO∆13, 5-LO∆4 and 5-LOp12, lacking the exons 13, 4 or a part of exon 12, respectively. We were able to detect the mRNA of the isoforms 5-LO∆13 and 5-LOp12 in B and T cell lines as well as in primary B and T cells and monocytes. Furthermore, we found that expression of 5-LO and particularly of the 5-LO∆13 and 5-LOp12 isoforms is increased in monocytes from patients with rheumatoid arthritis and sepsis. Confocal microscopy of HEK293T cells stably transfected with tagged 5-LO-WT and/or the isoforms revealed that 5-LO-WT is localized in the nucleus whereas all isoforms are located in the cytosol. Additionally, all isoforms are catalytically inactive and do not seem to influence the specific activity of 5-LO-WT. S271A mutation in 5-LO-WT and treatment of the cells with sorbitol or KN-93/SB203580 changes the localization of the WT enzyme to the cytosol. Despite colocalization with the S271A mutant, the isoforms did not affect LT biosynthesis. Analysis of the phosphorylation pattern of 5-LO-WT and all the isoforms revealed that 5-LOp12 and 5-LO∆13 are highly phosphorylated at Ser271 and 5-LOp12 at Ser523. Furthermore, coexpression of the isoforms inhibited or stimulated 5-LO-WT expression in transiently and stably transfected HEK293T cells suggesting that the isoforms have other functions than canonical LT biosynthesis.
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Affiliation(s)
- Ann-Katrin Ball
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Kim Beilstein
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Sandra Wittmann
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Duran Sürün
- Department of Molecular Hematology, Goethe University Medical School, 60590 Frankfurt am Main, Germany
| | - Meike J Saul
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Frank Schnütgen
- Department of Molecular Hematology, Goethe University Medical School, 60590 Frankfurt am Main, Germany
| | - Nicolas Flamand
- Centre de recherche de l'IUCPQ, Département de Médecine et Faculté de Médecine, Université Laval, Québec, QC G1V 4G5, Canada
| | - Ricardo Capelo
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Astrid S Kahnt
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Helena Frey
- General Pharmacology and Toxicology, Goethe-University Frankfurt, Theodor-Stern Kai 7, 60590 Frankfurt, Germany
| | - Liliana Schaefer
- General Pharmacology and Toxicology, Goethe-University Frankfurt, Theodor-Stern Kai 7, 60590 Frankfurt, Germany
| | - Rolf Marschalek
- Institute of Pharmaceutical Biology, Goethe-University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Ann-Kathrin Häfner
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany.
| | - Dieter Steinhilber
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany.
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19
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5-Lipoxygenase is a direct p53 target gene in humans. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2015; 1849:1003-16. [DOI: 10.1016/j.bbagrm.2015.06.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 05/19/2015] [Accepted: 06/07/2015] [Indexed: 11/18/2022]
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Abstract
Leukotrienes (LTs) are lipid mediators derived from the 5-lipoxygenase (5-LO) pathway of arachidonic acid metabolism and are markers and mediators of pulmonary inflammation. Research over the past two decades has established that LTs modulate inflammation in pulmonary arterial hypertension (PAH). The purpose of this review was to summarize the current knowledge of LTs in the pathophysiology of PAH and to highlight a recent study that advances our understanding of how leukotriene B4 (LTB4) specifically contributes to pulmonary vascular remodeling. The results of these studies suggest that pharmacological inhibition of LT pathways, especially LTB4, has high potential for the treatment of PAH.
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21
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Magi S, Takemoto Y, Kobayashi H, Kasamatsu M, Akita T, Tanaka A, Takano K, Tashiro E, Igarashi Y, Imoto M. 5-Lipoxygenase and cysteinyl leukotriene receptor 1 regulate epidermal growth factor-induced cell migration through Tiam1 upregulation and Rac1 activation. Cancer Sci 2014; 105:290-6. [PMID: 24350867 PMCID: PMC4317946 DOI: 10.1111/cas.12340] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 12/12/2013] [Accepted: 12/14/2013] [Indexed: 12/18/2022] Open
Abstract
Cell migration is an essential step for tumor metastasis. The small GTPase Rac1 plays an important role in cell migration. Previously, we reported that epidermal growth factor (EGF) induced two waves of Rac1 activation; namely, at 5 min and 12 h after stimulation. A second wave of EGF-induced Rac1 activation was required for EGF-induced cell migration, however, the spatiotemporal regulation of the second wave of EGF-induced Rac1 activation remains largely unclear. In this study, we found that 5-lipoxygenase (5-LOX) is activated in the process of EGF-induced cell migration, and that leukotriene C4 (LTC4) produced by 5-LOX mediated the second wave of Rac1 activation, as well as cell migration. Furthermore, these effects caused by LTC4 were found to be blocked in the presence of the antagonist of cysteinyl leukotriene receptor 1 (CysLT1). This blockage indicates that LTC4-mediated CysLT1 signaling regulates the second EGF-induced wave of Rac1 activation. We also found that 5-LOX inhibitors, CysLT1 antagonists and the knockdown of CysLT1 inhibited EGF-induced T cell lymphoma invasion and metastasis-inducing protein 1 (Tiam1) expression. Tiam1 expression is required for the second wave of EGF-induced Rac1 activation in A431 cells. Therefore, our results indicate that the 5-LOX/LTC4/CysLT1 signaling pathway regulates EGF-induced cell migration by increasing Tiam1 expression, leading to a second wave of Rac1 activation. Thus, CysLT1 may serve as a new molecular target for antimetastatic therapy. In addition, the CysLT1 antagonist, montelukast, which is used clinically for allergy treatment, might have great potential as a novel type of antimetastatic agent.
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Affiliation(s)
- Shigeyuki Magi
- Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, Yokohama, Japan
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23
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Rao CV, Janakiram NB, Mohammed A. Lipoxygenase and Cyclooxygenase Pathways and Colorectal Cancer Prevention. CURRENT COLORECTAL CANCER REPORTS 2012; 8:316-324. [PMID: 23293573 PMCID: PMC3535427 DOI: 10.1007/s11888-012-0146-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Colorectal cancer is one of the commonest malignancies in both men and women. In spite of significant progress in screening and in surgical and therapeutic interventions, colorectal cancer (CRC) is still a major public health problem. Accumulating evidence suggests that targeting inflammatory pathways may provide protection against the development of CRC. Eicosanoids derived from the enzymes cyclooxygenase (COX) and lipoxygenase (LOX) may contribute to CRC carcinogenesis. Approaches for targeting COX-1 and COX-2 with traditional nonsteroidal anti-inflammatory agents or targeting COX-2 with specific inhibitors are highly successful at the preclinical and clinical levels; however, large-scale clinical applicability of these agents is limited owing to unwanted side effects. Emerging studies suggests that 5-LOX-derived leukotrienes may contribute to colon tumor development and risk of thrombotic events. Thus, developing drugs that target both 5-LOX and COX-2 may provide a safer strategy. In this review, we discuss evidence for the involvement of 5-LOX in colon tumor development and targeting 5-LOX and COX-2 with synthetic and naturally occurring agents for CRC prevention.
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Affiliation(s)
- Chinthalapally V Rao
- Center for Cancer Prevention and Drug Development, Medical Oncology, Department of Medicine, PC Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
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Thangapandian S, John S, Lazar P, Choi S, Lee KW. Structural origins for the loss of catalytic activities of bifunctional human LTA4H revealed through molecular dynamics simulations. PLoS One 2012; 7:e41063. [PMID: 22848428 PMCID: PMC3405069 DOI: 10.1371/journal.pone.0041063] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Accepted: 06/17/2012] [Indexed: 12/18/2022] Open
Abstract
Human leukotriene A4 hydrolase (hLTA4H), which is the final and rate-limiting enzyme of arachidonic acid pathway, converts the unstable epoxide LTA4 to a proinflammatory lipid mediator LTB4 through its hydrolase function. The LTA4H is a bi-functional enzyme that also exhibits aminopeptidase activity with a preference over arginyl tripeptides. Various mutations including E271Q, R563A, and K565A have completely or partially abolished both the functions of this enzyme. The crystal structures with these mutations have not shown any structural changes to address the loss of functions. Molecular dynamics simulations of LTA4 and tripeptide complex structures with functional mutations were performed to investigate the structural and conformation changes that scripts the observed differences in catalytic functions. The observed protein-ligand hydrogen bonds and distances between the important catalytic components have correlated well with the experimental results. This study also confirms based on the structural observation that E271 is very important for both the functions as it holds the catalytic metal ion at its location for the catalysis and it also acts as N-terminal recognition residue during peptide binding. The comparison of binding modes of substrates revealed the structural changes explaining the importance of R563 and K565 residues and the required alignment of substrate at the active site. The results of this study provide valuable information to be utilized in designing potent hLTA4H inhibitors as anti-inflammatory agents.
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Affiliation(s)
- Sundarapandian Thangapandian
- Division of Applied Life Science (BK21 Program), Systems and Synthetic Agrobiotech Center, Plant Molecular Biology and Biotechnology Research Center, Research Institute of Natural Science, Gyeongsang National University, Jinju, Republic of Korea
- College of Pharmacy, Division of Life and Pharmaceutical Sciences and National Core Research Center for Cell Signaling and Drug Discovery Research, Ewha Womans University, Seoul, Republic of Korea
| | - Shalini John
- Division of Applied Life Science (BK21 Program), Systems and Synthetic Agrobiotech Center, Plant Molecular Biology and Biotechnology Research Center, Research Institute of Natural Science, Gyeongsang National University, Jinju, Republic of Korea
| | - Prettina Lazar
- Division of Applied Life Science (BK21 Program), Systems and Synthetic Agrobiotech Center, Plant Molecular Biology and Biotechnology Research Center, Research Institute of Natural Science, Gyeongsang National University, Jinju, Republic of Korea
| | - Sun Choi
- College of Pharmacy, Division of Life and Pharmaceutical Sciences and National Core Research Center for Cell Signaling and Drug Discovery Research, Ewha Womans University, Seoul, Republic of Korea
| | - Keun Woo Lee
- Division of Applied Life Science (BK21 Program), Systems and Synthetic Agrobiotech Center, Plant Molecular Biology and Biotechnology Research Center, Research Institute of Natural Science, Gyeongsang National University, Jinju, Republic of Korea
- * E-mail:
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Häfner AK, Cernescu M, Hofmann B, Ermisch M, Hörnig M, Metzner J, Schneider G, Brutschy B, Steinhilber D. Dimerization of human 5-lipoxygenase. Biol Chem 2012; 392:1097-111. [PMID: 22050225 DOI: 10.1515/bc.2011.200] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Human 5-lipoxygenase (5-LO) can form dimers as shown here via native gel electrophoresis, gel filtration chromatography and LILBID (laser induced liquid bead ion desorption) mass spectrometry. After glutathionylation of 5-LO by diamide/glutathione treatment, dimeric 5-LO was no longer detectable and 5-LO almost exclusively exists in the monomeric form which showed full catalytic activity. Incubation of 5-LO with diamide alone led to a disulfide-bridged dimer and to oligomer formation which displays a strongly reduced catalytic activity. The bioinformatic analysis of the 5-LO surface for putative protein-protein interaction domains and molecular modeling of the dimer interface suggests a head to tail orientation of the dimer which also explains the localization of previously reported ATP binding sites. This interface domain was confirmed by the observation that 5-LO dimer formation and inhibition of activity by diamide was largely prevented when four cysteines (C159S, C300S, C416S, C418S) in this domain were mutated to serines.
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Affiliation(s)
- Ann-Kathrin Häfner
- Institute of Pharmaceutical Chemistry/ZAFES, University of Frankfurt, Max-von-Laue-Strasse 9, 60438 Frankfurt, Germany
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26
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Häfner AK, Cernescu M, Hofmann B, Ermisch M, Hörnig M, Metzner J, Schneider G, Brutschy B, Steinhilber D. Dimerization of human 5-lipoxygenase. Biol Chem 2011. [PMID: 22050225 DOI: 10.1515/bc-2011-200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Human 5-lipoxygenase (5-LO) can form dimers as shown here via native gel electrophoresis, gel filtration chromatography and LILBID (laser induced liquid bead ion desorption) mass spectrometry. After glutathionylation of 5-LO by diamide/glutathione treatment, dimeric 5-LO was no longer detectable and 5-LO almost exclusively exists in the monomeric form which showed full catalytic activity. Incubation of 5-LO with diamide alone led to a disulfide-bridged dimer and to oligomer formation which displays a strongly reduced catalytic activity. The bioinformatic analysis of the 5-LO surface for putative protein-protein interaction domains and molecular modeling of the dimer interface suggests a head to tail orientation of the dimer which also explains the localization of previously reported ATP binding sites. This interface domain was confirmed by the observation that 5-LO dimer formation and inhibition of activity by diamide was largely prevented when four cysteines (C159S, C300S, C416S, C418S) in this domain were mutated to serines.
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Affiliation(s)
- Ann-Kathrin Häfner
- Institute of Pharmaceutical Chemistry/ZAFES, University of Frankfurt, Max-von-Laue-Strasse 9, 60438 Frankfurt, Germany
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27
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Applications of stereospecifically-labeled Fatty acids in oxygenase and desaturase biochemistry. Lipids 2011; 47:101-16. [PMID: 21971646 DOI: 10.1007/s11745-011-3612-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Accepted: 08/30/2011] [Indexed: 10/17/2022]
Abstract
Oxygenation and desaturation reactions are inherently associated with the abstraction of a hydrogen from the fatty acid substrate. Since the first published application in 1965, stereospecific placement of a labeled hydrogen isotope (deuterium or tritium) at the reacting carbons has proven a highly effective strategy for investigating the chemical mechanisms catalyzed by lipoxygenases, hemoprotein fatty acid dioxygenases including cyclooxygenases, cytochromes P450, and also the desaturases and isomerases. This review presents a synopsis of all published studies through 2010 on the synthesis and use of stereospecifically labeled fatty acids (71 references), and highlights some of the mechanistic insights gained by application of stereospecifically labeled fatty acids.
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28
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Haeggström JZ, Funk CD. Lipoxygenase and leukotriene pathways: biochemistry, biology, and roles in disease. Chem Rev 2011; 111:5866-98. [PMID: 21936577 DOI: 10.1021/cr200246d] [Citation(s) in RCA: 609] [Impact Index Per Article: 46.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Jesper Z Haeggström
- Department of Medical Biochemistry and Biophysics, Division of Chemistry 2, Karolinska Institutet, S-171 77 Stockholm, Sweden.
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Andoh T, Haza S, Saito A, Kuraishi Y. Involvement of leukotriene B4 in spontaneous itch-related behaviour in NC mice with atopic dermatitis-like skin lesions. Exp Dermatol 2011; 20:894-8. [DOI: 10.1111/j.1600-0625.2011.01346.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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30
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Affiliation(s)
- Motonao Nakamura
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, The University of Tokyo, Hongo, Tokyo, Japan.
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Zheng Y, Brash AR. Formation of a cyclopropyl epoxide via a leukotriene A synthase-related pathway in an anaerobic reaction of soybean lipoxygenase-1 with 15S-hydroperoxyeicosatetraenoic acid: evidence that oxygen access is a determinant of secondary reactions with fatty acid hydroperoxides. J Biol Chem 2010; 285:13427-36. [PMID: 20194505 PMCID: PMC2859502 DOI: 10.1074/jbc.m109.084632] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2009] [Revised: 01/29/2010] [Indexed: 11/06/2022] Open
Abstract
The further conversion of an arachidonic acid hydroperoxide to a leukotriene A (LTA) type epoxide by specific lipoxygenase (LOX) enzymes constitutes a key step in inflammatory mediator biosynthesis. Whereas mammalian 5-LOX transforms its primary product (5S-hydroperoxyeicosatetraenoic acid; 5S-HPETE) almost exclusively to LTA(4), the model enzyme, soybean LOX-1, normally produces no detectable leukotrienes and instead further oxygenates its primary product 15S-HPETE to 5,15- and 8,15-dihydroperoxides. Mammalian 15-LOX-1 displays both types of activity. We reasoned that availability of molecular oxygen within the LOX active site favors oxygenation, whereas lack of O(2) promotes LTA epoxide synthesis. To test this, we reacted 15S-HPETE with soybean LOX-1 under anaerobic conditions and identified the products by high pressure liquid chromatography, UV, mass spectrometry, and NMR. Among the products, we identified a pair of 8,15-dihydroxy diastereomers with all-trans-conjugated trienes that incorporated (18)O from H(2)(18)O at C-8, indicative of the formation of 14,15-LTA(4). A pair of 5,15-dihydroxy diastereomers containing two trans,trans-conjugated dienes (6E,8E,11E,13E) and that incorporated (18)O from H(2)(18)O at C-5 was deduced to arise from hydrolysis of a novel epoxide containing a cyclopropyl ring, 14,15-epoxy-[9,10,11-cyclopropyl]-eicosa-5Z,7E,13E-trienoic acid. Also identified was the delta-lactone of the 5,15-diol, a derivative that exhibited no (18)O incorporation due to its formation by intramolecular reaction of the carboxyl anion with the proposed epoxide intermediate. Our results support a model in which access to molecular oxygen within the active site directs the outcome from competing pathways in the secondary reactions of lipoxygenases.
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Affiliation(s)
- Yuxiang Zheng
- From the Department of Pharmacology and the Vanderbilt Institute of Chemical Biology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - Alan R. Brash
- From the Department of Pharmacology and the Vanderbilt Institute of Chemical Biology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232
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Detection of 5-lipoxygenase activity in the liverwort Marchantia polymorpha L. Biosci Biotechnol Biochem 2009; 73:2549-51. [PMID: 19897893 DOI: 10.1271/bbb.90479] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We detected 5-LOX (arachidonate 5-lipoxygenase) in the homogenate of Marchantia polymorpha by spectrophotometry and mass spectrometry. LC/MS/MS analysis indicated that the liverwort 5-LOX produced 5-hydroperoxy-6,8,11,14-eicosatetraenoic acid (5-HPETE) with arachidonic acid as a substrate. The 5-LOX activity showed a Ca(2+) response, as demonstrated for human 5-LOX. These findings suggest that the liverwort utilizes an arachidonate cascade in a defense signal response.
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Wecksler AT, Kenyon V, Garcia NK, Deschamps JD, van der Donk WA, Holman TR. Kinetic and structural investigations of the allosteric site in human epithelial 15-lipoxygenase-2. Biochemistry 2009; 48:8721-30. [PMID: 19645454 DOI: 10.1021/bi9009242] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Allosteric regulation of human lipoxygenase (hLO) activity has recently been implicated in the cellular biology of prostate cancer. In the current work, we present isotope effect, pH, and substrate inhibitor data of epithelial 15-hLO-2, which probe the allosteric effects on its mechanistic behavior. The Dk(cat)/KM for 15-hLO-2, with AA and LA as substrate, is large indicating hydrogen atom abstraction is the principle rate-determining step, involving a tunneling mechanism for both substrates. For AA, there are multiple rate determining steps (RDS) at both high and low temperatures, with both diffusion and hydrogen bonding rearrangements contributing at high temperature, but only hydrogen bonding rearrangements contributing at low temperature. The observed kinetic dependency on the hydrogen bonding rearrangement is eliminated upon addition of the allosteric effector, 13-(S)-hydroxyoctadecadienoic acid (13-HODE), and no allosteric effects were seen on diffusion or hydrogen atom abstraction. The (k(cat)/KM)AA/(k(cat)/KM)LA ratio was observed to have a pH dependence, which was fit with a titration curve (pKa = 7.7), suggesting the protonation of a histidine residue, which could hydrogen bond with the carboxylate of 13-HODE. Assuming this interaction, 13-HODE was docked to the solvent exposed histidines of a 15-hLO-2 homology model and found to bind well with H627, suggesting a potential location for the allosteric site. Utilizing d31-LA as an inhibitor, it was demonstrated that the binding of d31-LA to the allosteric site changes the conformation of 15-hLO-2 such that the affinity for substrate increases. This result suggests that allosteric binding locks the enzyme into a catalytically competent state, which facilitates binding of LA and decreases the (k(cat)/KM)AA/(k(cat)/KM)LA ratio. Finally, the magnitude of the 13-HODE KD for 15-hLO-2 is over 200-fold lower than that of 13-HODE for 15-hLO-1, changing the substrate specificity of 15-hLO-2 to 1.9. This would alter the LO product distribution and increase the production of the pro-tumorigenic, 13-HODE, possibly representing a pro-tumorigenic feedback loop for 13-HODE and 15-hLO-2.
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Affiliation(s)
- Aaron T Wecksler
- Chemistry and Biochemistry Department, University of California, Santa Cruz, California 95064, USA
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Shimizu T. Lipid mediators in health and disease: enzymes and receptors as therapeutic targets for the regulation of immunity and inflammation. Annu Rev Pharmacol Toxicol 2009; 49:123-50. [PMID: 18834304 DOI: 10.1146/annurev.pharmtox.011008.145616] [Citation(s) in RCA: 430] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Prostaglandins, leukotrienes, platelet-activating factor, lysophosphatidic acid, sphingosine 1-phosphate, and endocannabinoids, collectively referred to as lipid mediators, play pivotal roles in immune regulation and self-defense, and in the maintenance of homeostasis in living systems. They are produced by multistep enzymatic pathways, which are initiated by the de-esterification of membrane phospholipids by phospholipase A2s or sphingo-myelinase. Lipid mediators exert their biological effects by binding to cognate receptors, which are members of the G protein-coupled receptor superfamily. The synthesis of the lipid mediators and subsequent induction of receptor activity is tightly regulated under normal physiological conditions, and enzyme and/or receptor dysfunction can lead to a variety of disease conditions. Thus, the manipulation of lipid mediator signaling, through either enzyme inhibitors or receptor antagonists and agonists, has great potential as a therapeutic approach to disease. In this review, I summarize our current state of knowledge of the synthesis of lipid mediators and the function of their cognate receptors, and discuss the effects of genetic or pharmacological ablation of enzyme or receptor function on various pathophysiological processes.
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Affiliation(s)
- Takao Shimizu
- Department of Biochemistry and Molecular Biology, The University of Tokyo, Tokyo 113-0033, Japan.
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35
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Hikiji H, Takato T, Shimizu T, Ishii S. The roles of prostanoids, leukotrienes, and platelet-activating factor in bone metabolism and disease. Prog Lipid Res 2008; 47:107-26. [DOI: 10.1016/j.plipres.2007.12.003] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2007] [Revised: 11/29/2007] [Accepted: 12/04/2007] [Indexed: 12/11/2022]
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Enzymatic synthesis of a bicyclobutane fatty acid by a hemoprotein lipoxygenase fusion protein from the cyanobacterium Anabaena PCC 7120. Proc Natl Acad Sci U S A 2007; 104:18941-5. [PMID: 18025466 DOI: 10.1073/pnas.0707148104] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Biological transformations of polyunsaturated fatty acids often lead to chemically unstable products, such as the prostaglandin endoperoxides and leukotriene A(4) epoxide of mammalian biology and the allene epoxides of plants. Here, we report on the enzymatic production of a fatty acid containing a highly strained bicyclic four-carbon ring, a moiety known previously only as a model compound for mechanistic studies in chemistry. Starting from linolenic acid (C18.3omega3), a dual function protein from the cyanobacterium Anabaena PCC 7120 forms 9R-hydroperoxy-C18.3omega3 in a lipoxygenase domain, then a catalase-related domain converts the 9R-hydroperoxide to two unstable allylic epoxides. We isolated and identified the major product as 9R,10R-epoxy-11trans-C18.1 containing a bicyclo[1.1.0]butyl ring on carbons 13-16, and the minor product as 9R,10R-epoxy-11trans,13trans,15cis-C18.omega3, an epoxide of the leukotriene A type. Synthesis of both epoxides can be understood by initial transformation of the hydroperoxide to an epoxy allylic carbocation. Rearrangement to an intermediate bicyclobutonium ion followed by deprotonation gives the bicyclobutane fatty acid. This enzymatic reaction has no parallel in aqueous or organic solvent, where ring-opened cyclopropanes, cyclobutanes, and homoallyl products are formed. Given the capability shown here for enzymatic formation of the highly strained and unstable bicyclobutane, our findings suggest that other transformations involving carbocation rearrangement, in both chemistry and biology, should be examined for the production of the high energy bicyclobutanes.
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Rådmark O, Samuelsson B. 5-Lipoxygenase: Regulation and possible involvement in atherosclerosis. Prostaglandins Other Lipid Mediat 2007; 83:162-74. [PMID: 17481551 DOI: 10.1016/j.prostaglandins.2007.01.003] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
This review article focuses on two aspects regarding 5-lipoxygenase. First, mechanisms for activation of the enzyme. Second, the involvement of 5-lipoxygenase and leukotrienes in atherosclerosis.
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Affiliation(s)
- Olof Rådmark
- Department of Medical Biochemistry and Biophysics, Division of Physiological Chemistry II, Karolinska Institute, S-17177 Stockholm, Sweden.
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Rådmark O, Samuelsson B. Regulation of 5-lipoxygenase enzyme activity. Biochem Biophys Res Commun 2005; 338:102-10. [PMID: 16122704 DOI: 10.1016/j.bbrc.2005.08.013] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2005] [Accepted: 08/04/2005] [Indexed: 11/27/2022]
Abstract
In this article, regulation of human 5-lipoxygenase enzyme activity is reviewed. First, structural properties and enzyme activities are described. This is followed by the activating factors: Ca2+, membranes, ATP, and lipid hydroperoxide. Also, studies on phosphorylation of 5-lipoxygenase and nuclear localization sequences are reviewed.
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Affiliation(s)
- Olof Rådmark
- Department of Medical Biochemistry and Biophysics, Division of Physiological Chemistry II, Karolinska Institutet, S-17177 Stockholm, Sweden.
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39
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Hanaka H, Shimizu T, Izumi T. Stress-induced nuclear export of 5-lipoxygenase. Biochem Biophys Res Commun 2005; 338:111-6. [PMID: 16165096 DOI: 10.1016/j.bbrc.2005.09.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2005] [Revised: 08/25/2005] [Accepted: 09/01/2005] [Indexed: 11/30/2022]
Abstract
A key enzyme for leukotriene biosynthesis is 5-lipoxygenase (5-LO), which we found is exported from the nucleus when p38 MAPK is activated. CHO-K1 cells stably express green fluorescent protein-5-lipoxygenase fusion protein (GFP-5LO), which is located predominantly in the nucleus, and is exported by anisomycin, hydrogen peroxide, and sorbitol, with activation of p38 MAPK. SB203580, an inhibitor of p38 MAPK, and Leptomycin B, an inhibitor of the nuclear export, blocked the anisomycin-induced export of GFP-5LO. When HEK293 cells were transformed with plasmids for wild-type GFP-5LO, GFP-5LO-S271A or GFP-5LO-S271E mutants, most wild-type GFP-5LO and GFP-5LO-S271A localized in the nucleus, but GFP-5LO-S271E localized in the cytosol. Thus, phosphorylation at Ser-271 of 5-LO is important for its export. Endogenous 5-LO in RBL cells stimulated with anisomycin was also exported from the nucleus. These results suggest that the nuclear export of 5-LO depends on the stress-induced activation of the p38 MAPK pathway.
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Affiliation(s)
- Hiromi Hanaka
- Department of Molecular Biochemistry, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan
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40
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Haynes A, Shaik MS, Chatterjee A, Singh M. Formulation and evaluation of aerosolized celecoxib for the treatment of lung cancer. Pharm Res 2005; 22:427-39. [PMID: 15835749 DOI: 10.1007/s11095-004-1881-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
PURPOSE We examined the effect of aerosolized celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, on the in vitro cytotoxicity and apoptotic response of docetaxel against the human lung carcinoma cell lines A549 and H460. METHODS A metered dose inhaler (MDI) formulation of celecoxib was prepared and evaluated for its medication delivery and aerodynamic properties. The in vitro cytotoxicity of the aerosolized celecoxib-MDI alone or in combination with docetaxel was assessed using a six-stage viable impactor by a previously established method. The induction of apoptosis was evaluated by morphologic examination (acridine orange and Hoechst staining) and DNA fragmentation. Furthermore, in an attempt to identify molecular targets involved in the anticancer mechanisms of celecoxib and docetaxel, we examined their effect on the expression of an array of markers involved in the COX-2 dependent and independent pathways. RESULTS The celecoxib-MDI had a medication delivery of 231.3 microg/shot, mass median aerodynamic diameter (MMAD) of 1.4 microm (GSD = 1.9), and respirable fraction of 50.7%. The celecoxib-MDI (2 shots) in combination with docetaxel had cell kills as high as 81.3% and 67.7% in A549 and H460 cells, respectively. Hoechst and acridine orange staining showed an enhanced induction of apoptosis in A549 and H460 cells exposed to aerosolized celecoxib with docetaxel, which was further confirmed by DNA fragmentation. Western blot analysis showed a significant reduction in cPLA2 expression in both A549 and H460 cells treated with the combination of celecoxib with docetaxel. In the COX-2 independent pathway, there was a significant increase in the expression of PPAR-gamma and p53, whereas pro-caspase-3 expression was significantly decreased, which may contribute to the enhanced apoptotic response observed with the combination treatment. CONCLUSIONS Our results suggest that aerosolized celecoxib significantly enhances the in vitro cytotoxicity and apoptotic response of docetaxel against A549 and H460 cells, and this enhanced activity is mediated via alterations in expression of various molecular targets involved in apoptosis.
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Affiliation(s)
- Alfred Haynes
- College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida 32307, USA
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41
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Iizuka Y, Yokomizo T, Terawaki K, Komine M, Tamaki K, Shimizu T. Characterization of a Mouse Second Leukotriene B4 Receptor, mBLT2. J Biol Chem 2005; 280:24816-23. [PMID: 15866883 DOI: 10.1074/jbc.m413257200] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Leukotriene B4 (LTB4) is a potent chemoattractant and activator for granulocytes and macrophages and is considered to be an inflammatory mediator. Two G-protein-coupled receptors for LTB4, BLT1 and BLT2, have been cloned from human and shown to be high and low affinity LTB4 receptors, respectively. To reveal the biological roles of BLT2 using mouse disease models, we cloned and characterized mouse BLT2. Chinese hamster ovary cells stably expressing mouse BLT2 exhibited specific binding to LTB4, LTB4-induced calcium mobilization, inhibition of adenylyl cyclase, and phosphorylation of extracellular signal-regulated kinase. We found that Compound A (4'-{[pentanoyl (phenyl) amino] methyl}-1, 1'-biphenyl-2-carboxylic acid) was a BLT2-selective agonist and induced Ca(2+) mobilization and phosphorylation of extracellular signal-regulated kinase through BLT2, whereas it had no effect on BLT1. 12-epi LTB4 exhibited a partial agonistic activity against mBLT1 and mBLT2, whereas 6-trans-12-epi LTB4 did not. Northern blot analysis showed that mouse BLT2 is expressed highly in small intestine and skin in contrast to the ubiquitous expression of human BLT2. By in situ hybridization and the reverse transcriptase polymerase chain reaction, we demonstrated that mouse BLT2 is expressed in follicular and interfollicular keratinocytes. Compound A, LTB4, and 12-epi LTB4 all induced phosphorylation of extracellular signal-regulated kinase in primary mouse keratinocytes. Furthermore, Compound A and LTB4 induced chemotaxis in primary mouse keratinocytes. These data suggest the presence of functional BLT2 in primary keratinocytes.
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Affiliation(s)
- Yoshiko Iizuka
- Departments of Biochemistry and Molecular Biology and Dermatology, Faculty of Medicine, The University of Tokyo, Tokyo, Japan
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42
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Ye YN, Liu ESL, Shin VY, Wu WKK, Cho CH. Contributory role of 5-lipoxygenase and its association with angiogenesis in the promotion of inflammation-associated colonic tumorigenesis by cigarette smoking. Toxicology 2004; 203:179-88. [PMID: 15363593 DOI: 10.1016/j.tox.2004.06.004] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2004] [Revised: 06/03/2004] [Accepted: 06/04/2004] [Indexed: 01/03/2023]
Abstract
Our previous study shows that cigarette smoking can promote inflammation-associated adenoma formation in the mouse colon, but the underlying mechanism remains unknown. Several studies suggest that there is a link between 5-lipoxygenase (5-LOX) and carcinogenesis in humans and animals. In the present study, we aims to investigate whether the promoting action of cigarette smoke on inflammation-associated colon cancer formation is associated with 5-LOX activation in mice. Results showed that exposure to the mainstream smoke of unfiltered cigarettes enhanced the 5-LOX protein expression in the inflammation-associated colonic adenomas. It was accompanied with an up-regulation of matrix metalloproteinase-2 (MMP-2) and vascular endothelial growth factor (VEGF). Both are the key angiogenic factors for tumorigenesis. 5-LOX inhibitors decreased the incidence of colonic adenoma formation and reduced angiogenesis, MMP-2 activity and VEGF protein expression in the colons of these animals. Taken together, these results strongly suggest that cigarette smoke can induce 5-LOX expression which plays an important role in activation of MMP-2 and VEGF to induce angiogenic process and promotion of inflammation-associated adenoma formation in mice.
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Affiliation(s)
- Yi-Ni Ye
- Department of Pharmacology, Faculty of Medicine, Zhejiang University, Hangzhou, China
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Abstract
The initial steps in the biosynthesis of leukotrienes from arachidonic acid are carried out by the enzyme 5-lipoxygenase (5-LO). In intact cells, the helper protein 5-LO activating protein (FLAP) is necessary for efficient enzyme utilization of endogenous substrate. The last decade has witnessed remarkable progress in our understanding of these two proteins. Here we review the molecular and cellular aspects of the expression, function, and regulation of 5-LO and FLAP.
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Affiliation(s)
- M Peters-Golden
- Department of Internal Medicine, University of Michigan Health System, 1150 W Medical Center Drive, Ann Arbor, MI 48109-0642, USA.
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Kuhn H, Anton M, Gerth C, Habenicht A. Amino acid differences in the deduced 5-lipoxygenase sequence of CAST atherosclerosis-resistance mice confer impaired activity when introduced into the human ortholog. Arterioscler Thromb Vasc Biol 2003; 23:1072-6. [PMID: 12730086 DOI: 10.1161/01.atv.0000074167.01184.48] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE The mouse strain CON6, which was generated by breeding athero-resistant CAST mice into an athero-susceptible B6 background, exhibits almost complete resistance to atherosclerosis. An athero-resistance gene cluster has been localized at the central region of chromosome 6, and among the candidate genes of this locus, the 5-lipoxygenase has attracted particular attention because of its involvement in the biosynthesis of proinflammatory leukotrienes. Comparison of 5-lipoxygenase genomic sequences of B6 and CON6 mice indicated 2 conserved amino acid exchanges in the CON6 animals, but the functional impact of these mutations has not been defined. METHODS AND RESULTS We analyzed the functionality of these amino acid exchanges relative to essential catalytic properties (specific activity, substrate affinity, and reaction specificity) and found that these mutations confer an impaired lipoxygenase and leukotriene A4-synthase activity when introduced into the human enzyme. In contrast, substrate affinity, enantiomer selectivity, and positional specificity remained unchanged. CONCLUSIONS These data are consistent with the possibility that naturally occurring conservative mutations in the coding region of the murine 5-lipoxygenase gene can significantly affect enzyme activity and that this loss of function may be involved in CAST/CON6 athero-resistance.
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Affiliation(s)
- Hartmut Kuhn
- Institute of Biochemistry, Humboldt University Medical School Charité, Berlin, Germany.
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Reddanna P, Prabhu KS, Whelan J, Reddy CC. Carboxypeptidase A-catalyzed direct conversion of leukotriene C4 to leukotriene F4. Arch Biochem Biophys 2003; 413:158-63. [PMID: 12729612 DOI: 10.1016/s0003-9861(03)00080-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Leukotrienes (LTs) are 5-lipoxygenase (5-LO)-derived arachidonic metabolites that constitute a potent set of lipid mediators produced by inflammatory cells. Leukotriene A(4), a labile allylic epoxide formed from arachidonic acid by dual 5-LO activity, is the precursor for LTB(4) and LTC(4) synthesis. LTC(4) is further transformed enzymatically by the sequential action of gamma-glutamyltranspeptidase and dipeptidase to LTD(4) and LTE(4), respectively. In this report, we present evidence that bovine pancreatic carboxypeptidase A (CPA), which shares significant sequence homology with CPA in mast cell granules, catalyzes the conversion of LTC(4) to LTF(4) via the hydrolysis of an amide bond. The identity of CPA-catalyzed LTC(4) hydrolysis product as LTF(4) was confirmed by several analytical criteria, including enzymatic conversion to conjugated tetraene by soybean LO, conversion to LTE(4) by gamma-glutamyltranspeptidase, cochromatography with the standard LTF(4) and positive-ion fast-atom bombardment mass spectral analysis. Thus, it appears that the physiological significance of this single-step transformation may point toward a major cellular homeostatic mechanism of metabolizing LTC(4), a potent bronco- and vasoconstrictor, to a less potent form of cysteinyl LTs.
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Affiliation(s)
- Pallu Reddanna
- College of Life Sciences, University of Hyderabad, Hyderabad 500134, India
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Zarini S, Murphy RC. Biosynthesis of 5-oxo-6,8,11,14-eicosatetraenoic acid from 5-hydroperoxyeicosatetraenoic acid in the murine macrophage. J Biol Chem 2003; 278:11190-6. [PMID: 12547823 DOI: 10.1074/jbc.m208496200] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
5-Oxo-6,8,11,14-eicosatetraenoic acid (5-oxo-ETE) is a metabolite of arachidonic acid shown to possess important biological activities within different cell types. In the neutrophil, a specific NADP(+)-dependent dehydrogenase utilizes 5-lipoxygenase-derived 5-hydroxy-6,8,11,14-eicosatetraenoic acid (5(S)-HETE) as the required substrate. In the present study, 5-hydroperoxy-6,8,11,14-eicosatetraenoic acid (5-HpETE), rather than 5-HETE, was found to be the biosynthetic precursor of 5-oxo-ETE in the murine macrophage. The macrophage was not able to convert 5-HETE into 5-oxo-ETE even when preincubated with phorbol ester or with other lipid hydroperoxides. The factor responsible for the conversion of 5-HpETE into 5-oxo-ETE was found predominantly in the cytosolic fraction of the macrophage, with an approximate molecular weight of 50,000-60,000, as assessed by size exclusion chromatography. Formation of 5-oxo-ETE was rapid and the catalytic protein was found to have an apparent K(m) of 5.3 microM for the eicosanoid. Furthermore, the protein could efficiently utilize 5(R,S)-HpETE as substrate and was heat and protease labile. This novel pathway of 5-oxo-ETE biosynthesis in the murine macrophage was consistent with reduction of a 5-hydroperoxy group to an intermediate alkoxy radical that could be subsequently oxidized to the 5-oxo product. Such a mechanism would enable racemic 5-HpETE, derived from free radical oxidation of arachidonic acid, to be efficiently converted into this potent chemotactic eicosanoid.
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Affiliation(s)
- Simona Zarini
- Division of Cell Biology, Department of Pediatrics, National Jewish Medical and Research Center, Denver, Colorado 80206, USA
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Abstract
In this article, it has been attempted to review data primarily on the activation of human 5-lipoxygenase, in vitro and in the cell. First, structural properties and enzyme activities are described. This is followed by the activating factors: Ca2+, membranes, ATP, and lipid hydroperoxide. Also, studies on phosphorylation of 5-lipoxygenase, interaction with other proteins, and the intracellullar mobility of 5-lipoxygenase, are reviewed.
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Affiliation(s)
- Olof Rådmark
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.
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48
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Bürkert E, Rådmark O, Steinhilber D, Werz O. Monocyte-derived soluble protein confers 5-lipoxygenase activity Ca2+-dependent. Biochem Biophys Res Commun 2002; 295:985-91. [PMID: 12127993 DOI: 10.1016/s0006-291x(02)00791-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
5-Lipoxygenase (5-LO) is a Ca2+-stimulated enzyme that initializes the formation of proinflammatory leukotrienes from arachidonic acid (AA). In this report, we demonstrate that a soluble protein of the monocytic cell line Mono Mac 6 confers 5-LO activity Ca2+-dependent in vitro. Thus, in broken cell preparations of human polymorphonuclear leukocytes (PMNL) and rat basophilic leukemia (RBL)-1 cells, 5-LO converted AA (>20 microM) in the absence of Ca2+, whereas Ca2+ was absolutely required for 5-LO activity in broken cell preparations of MM6 cells. 5-LO partially purified from MM6 cells was substantially active in the absence of Ca2+. Recombination experiments revealed that the cytosolic fraction of MM6 cells contains a factor that suppresses the activity of partially purified 5-LO from PMNL, RBL-1, and MM6 cells in the absence but not in the presence of Ca2+. Further characterization showed that this factor is a 80-100 kDa heat-sensitive protein.
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Affiliation(s)
- Eva Bürkert
- Institute of Pharmaceutical Chemistry, University of Frankfurt, Frankfurt, Germany
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Hanaka H, Shimizu T, Izumi T. Nuclear-localization-signal-dependent and nuclear-export-signal-dependent mechanisms determine the localization of 5-lipoxygenase. Biochem J 2002; 361:505-14. [PMID: 11802780 PMCID: PMC1222333 DOI: 10.1042/0264-6021:3610505] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
5-Lipoxygenase (5-LO) metabolizes arachidonic acid to leukotriene A4, a key intermediate in leukotriene biosynthesis. To explore the molecular mechanisms of its cell-specific localization, a fusion protein between green fluorescent protein (GFP) and human 5-LO (GFP-5LO) was expressed in various cells. GFP-5LO was localized in the cytosol in HL-60 cells and in both the nucleus and the cytosol in RBL (rat basophilic leukaemia) cells, similarly to the native enzyme in these cells. The localization of GFP fusion proteins for mutant 5-LOs in a putative bipartite nuclear localization signal (NLS), amino acids 638-655, in Chinese hamster ovary (CHO)-K1 and Swiss3T3 cells revealed that this motif is important for the nuclear localization of 5-LO. A GFP fusion protein of this short peptide localized consistently in the nucleus. Leptomycin B, a specific inhibitor of nuclear export signal (NES)-dependent transport, diminished the cytosolic localization of 5-LO in HL-60 cells and that of GFP-5LO in CHO-K1 cells, suggesting that an NES-system might also function in determining 5-LO localization. Analysis of the localization of 5-LO during the cell cycle points to a controlled movement of this enzyme. Thus we conclude that a balance of NLS- and NES-dependent mechanisms determines the cell-type-specific localization of 5-LO, suggesting a nuclear function for this enzyme.
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Affiliation(s)
- Hiromi Hanaka
- Department of Biochemistry, Gunma University School of Medicine, 3-39-22 Showamachi, Maebashi, Gunma 371-8511, Japan
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Zhang YY, Hammarberg T, Radmark O, Samuelsson B, Ng CF, Funk CD, Loscalzo J. Analysis of a nucleotide-binding site of 5-lipoxygenase by affinity labelling: binding characteristics and amino acid sequences. Biochem J 2000; 351 Pt 3:697-707. [PMID: 11042125 PMCID: PMC1221410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
5-Lipoxygenase (5LO) catalyses the first two steps in the biosynthesis of leukotrienes, which are inflammatory mediators derived from arachidonic acid. 5LO activity is stimulated by ATP; however, a consensus ATP-binding site or nucleotide-binding site has not been found in its protein sequence. In the present study, affinity and photoaffinity labelling of 5LO with 5'-p-fluorosulphonylbenzoyladenosine (FSBA) and 2-azido-ATP showed that 5LO bound to the ATP analogues quantitatively and specifically and that the incorporation of either analogue inhibited ATP stimulation of 5LO activity. The stoichiometry of the labelling was 1.4 mol of FSBA/mol of 5LO (of which ATP competed with 1 mol/mol) or 0.94 mol of 2-azido-ATP/mol of 5LO (of which ATP competed with 0.77 mol/mol). Labelling with FSBA prevented further labelling with 2-azido-ATP, indicating that the same binding site was occupied by both analogues. Other nucleotides (ADP, AMP, GTP, CTP and UTP) also competed with 2-azido-ATP labelling, suggesting that the site was a general nucleotide-binding site rather than a strict ATP-binding site. Ca(2+), which also stimulates 5LO activity, had no effect on the labelling of the nucleotide-binding site. Digestion with trypsin and peptide sequencing showed that two fragments of 5LO were labelled by 2-azido-ATP. These fragments correspond to residues 73-83 (KYWLNDDWYLK, in single-letter amino acid code) and 193-209 (FMHMFQSSWNDFADFEK) in the 5LO sequence. Trp-75 and Trp-201 in these peptides were modified by the labelling, suggesting that they were immediately adjacent to the C-2 position of the adenine ring of ATP. Given the stoichiometry of the labelling, the two peptide sequences of 5LO were probably near each other in the enzyme's tertiary structure, composing or surrounding the ATP-binding site of 5LO.
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Affiliation(s)
- Y Y Zhang
- Whitaker Cardiovascular Institute, Boston University School of Medicine, 715 Albany Street, Boston, MA 02118, USA.
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