1
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Su KK, Zheng XH, Bréchot C, Zheng XP, Zhu DH, Huang R, Zhang YH, Tao JJ, Lou YJ, Li LJ. Five-lipoxygenase-activating protein-mediated CYLD attenuation is a candidate driver in hepatic malignant lesion. Front Oncol 2022; 12:912881. [PMID: 35978827 PMCID: PMC9376481 DOI: 10.3389/fonc.2022.912881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 06/30/2022] [Indexed: 11/13/2022] Open
Abstract
Hepatocellular carcinoma (HCC) is an inflammation-associated cancer. However, the lipid pro-inflammatory mediators have only been seldom investigated in HCC pathogenesis. Cylindromatosis (CYLD) attenuation is involved in hepatocarcinogenesis. Here, we aimed to evaluate the significance of hepatic lipid pro-inflammatory metabolites of arachidonate-affected CYLD expression via the 5-lipoxygenase (5-LO) pathway. Resection liver tissues from HCC patients or donors were evaluated for the correlation of 5-LO/cysteinyl leukotrienes (CysLTs) signaling to the expression of CYLD. The impact of functional components in 5-LO/CysLTs cascade on survival of HCC patients was subsequently assessed. Both livers from canines, a preponderant animal for cancer research, and genetic-modified human HCC cells treated with hepatocarcinogen aristolochic acid I (AAI) were further used to reveal the possible relevance between 5-LO pathway activation and CYLD suppression. Five-LO-activating protein (FLAP), an essential partner of 5-LO, was significantly overexpressed and was parallel to CYLD depression, CD34 neovascular localization, and high Ki-67 expression in the resection tissues from HCC patients. Importantly, high hepatic FLAP transcription markedly shortened the median survival time of HCC patients after surgical resection. In the livers of AAI-treated canines, FLAP overexpression was parallel to enhanced CysLTs contents and the simultaneous attenuation of CYLD. Moreover, knock-in FLAP significantly diminished the expression of CYLD in AAI-treated human HCC cells. In summary, the hepatic FLAP/CysLTs axis is a crucial suppressor of CYLD in HCC pathogenesis, which highlights a novel mechanism in hepatocarcinogenesis and progression. FLAP therefore can be explored for the early HCC detection and a target of anti-HCC therapy.
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Affiliation(s)
- Kun-kai Su
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- National Clinical Research Center for Infectious Diseases, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Xue-hua Zheng
- Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
- Department of Pharmacology, Shengjing Hospital, China Medical University, Shenyang, China
| | | | - Xiao-ping Zheng
- Department of Pathology, Shulan (Hangzhou) Hospital, Hangzhou, China
| | - Dan-hua Zhu
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- National Clinical Research Center for Infectious Diseases, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Rong Huang
- Department of Pathology, Shulan (Hangzhou) Hospital, Hangzhou, China
| | - Yan-hong Zhang
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- National Clinical Research Center for Infectious Diseases, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jing-jing Tao
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- National Clinical Research Center for Infectious Diseases, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yi-jia Lou
- Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Lan-juan Li
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- National Clinical Research Center for Infectious Diseases, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- *Correspondence: Lan-juan Li,
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2
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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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3
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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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4
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Ho JD, Lee MR, Rauch CT, Aznavour K, Park JS, Luz JG, Antonysamy S, Condon B, Maletic M, Zhang A, Hickey MJ, Hughes NE, Chandrasekhar S, Sloan AV, Gooding K, Harvey A, Yu XP, Kahl SD, Norman BH. Structure-based, multi-targeted drug discovery approach to eicosanoid inhibition: Dual inhibitors of mPGES-1 and 5-lipoxygenase activating protein (FLAP). Biochim Biophys Acta Gen Subj 2020; 1865:129800. [PMID: 33246032 DOI: 10.1016/j.bbagen.2020.129800] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 10/27/2020] [Accepted: 11/20/2020] [Indexed: 01/30/2023]
Abstract
BACKGROUND Due to the importance of both prostaglandins (PGs) and leukotrienes (LTs) as pro-inflammatory mediators, and the potential for eicosanoid shunting in the presence of pathway target inhibitors, we have investigated an approach to inhibiting the formation of both PGs and LTs as part of a multi-targeted drug discovery effort. METHODS We generated ligand-protein X-ray crystal structures of known inhibitors of microsomal prostaglandin E2 synthase-1 (mPGES-1) and the 5-Lipoxygenase Activating Protein (FLAP), with their respective proteins, to understand the overlapping pharmacophores. We subsequently used molecular modeling and structure-based drug design (SBDD) to identify hybrid structures intended to inhibit both targets. RESULTS This work enabled the preparation of compounds 4 and 5, which showed potent in vitro inhibition of both targets. SIGNIFICANCE Our findings enhance the structural understanding of mPGES-1 and FLAP's unique ligand binding pockets and should accelerate the discovery of additional dual inhibitors for these two important integral membrane protein drug targets.
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Affiliation(s)
- Joseph D Ho
- Lilly Biotechnology Center, San Diego, CA 92121, USA.
| | - Matthew R Lee
- Lilly Biotechnology Center, San Diego, CA 92121, USA
| | | | | | | | - John G Luz
- Lilly Biotechnology Center, San Diego, CA 92121, USA
| | | | | | - Milan Maletic
- Lilly Biotechnology Center, San Diego, CA 92121, USA
| | - Aiping Zhang
- Lilly Biotechnology Center, San Diego, CA 92121, USA
| | | | | | | | - Ashley V Sloan
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana 46285, USA
| | - Karen Gooding
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana 46285, USA
| | - Anita Harvey
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana 46285, USA
| | - Xiao-Peng Yu
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana 46285, USA
| | - Steven D Kahl
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana 46285, USA
| | - Bryan H Norman
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana 46285, USA.
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5
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Thulasingam M, Haeggström JZ. Integral Membrane Enzymes in Eicosanoid Metabolism: Structures, Mechanisms and Inhibitor Design. J Mol Biol 2020; 432:4999-5022. [PMID: 32745470 DOI: 10.1016/j.jmb.2020.07.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 07/20/2020] [Accepted: 07/22/2020] [Indexed: 12/14/2022]
Abstract
Eicosanoids are potent lipid mediators involved in central physiological processes such as hemostasis, renal function and parturition. When formed in excess, eicosanoids become critical players in a range of pathological conditions, in particular pain, fever, arthritis, asthma, cardiovascular disease and cancer. Eicosanoids are generated via oxidative metabolism of arachidonic acid along the cyclooxygenase (COX) and lipoxygenase (LOX) pathways. Specific lipid species are formed downstream of COX and LOX by specialized synthases, some of which reside on the nuclear and endoplasmic reticulum, including mPGES-1, FLAP, LTC4 synthase, and MGST2. These integral membrane proteins are members of the family "membrane-associated proteins in eicosanoid and glutathione metabolism" (MAPEG). Here we focus on this enzyme family, which encompasses six human members typically catalyzing glutathione dependent transformations of lipophilic substrates. Enzymes of this family have evolved to combat the topographical challenge and unfavorable energetics of bringing together two chemically different substrates, from cytosol and lipid bilayer, for catalysis within a membrane environment. Thus, structural understanding of these enzymes are of utmost importance to unravel their molecular mechanisms, mode of substrate entry and product release, in order to facilitate novel drug design against severe human diseases.
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Affiliation(s)
- Madhuranayaki Thulasingam
- Division of Physiological Chemistry II, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.
| | - Jesper Z Haeggström
- Division of Physiological Chemistry II, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.
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6
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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: 113] [Impact Index Per Article: 28.3] [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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7
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Schmider AB, Bauer NC, Sunwoo H, Godin MD, Ellis GE, Lee JT, Nigrovic PA, Soberman RJ. Two- and three-color STORM analysis reveals higher-order assembly of leukotriene synthetic complexes on the nuclear envelope of murine neutrophils. J Biol Chem 2020; 295:5761-5770. [PMID: 32152223 PMCID: PMC7186161 DOI: 10.1074/jbc.ra119.012069] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 02/24/2020] [Indexed: 11/06/2022] Open
Abstract
Over the last several years it has become clear that higher order assemblies on membranes, exemplified by signalosomes, are a paradigm for the regulation of many membrane signaling processes. We have recently combined two-color direct stochastic optical reconstruction microscopy (dSTORM) with the (Clus-DoC) algorithm that combines cluster detection and colocalization analysis to observe the organization of 5-lipoxygenase (5-LO) and 5-lipoxygenase-activating protein (FLAP) into higher order assemblies on the nuclear envelope of mast cells; these assemblies were linked to leukotriene (LT) C4 production. In this study we investigated whether higher order assemblies of 5-LO and FLAP included cytosolic phospholipase A2 (cPLA2) and were linked to LTB4 production in murine neutrophils. Using two- and three-color dSTORM supported by fluorescence lifetime imaging microscopy we identified higher order assemblies containing 40 molecules (median) (IQR: 23, 87) of 5-LO, and 53 molecules (62, 156) of FLAP monomer. 98 (18, 154) molecules of cPLA2 were clustered with 5-LO, and 77 (33, 114) molecules of cPLA2 were associated with FLAP. These assemblies were tightly linked to LTB4 formation. The activation-dependent close associations of cPLA2, FLAP, and 5-LO in higher order assemblies on the nuclear envelope support a model in which arachidonic acid is generated by cPLA2 in apposition to FLAP, facilitating its transfer to 5-LO to initiate LT synthesis.
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Affiliation(s)
- Angela B Schmider
- Nephrology Division, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129
| | - Nicholas C Bauer
- Nephrology Division, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129
| | - Hongjae Sunwoo
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts 02114
| | - Matthew D Godin
- Nephrology Division, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129
| | - Giorgianna E Ellis
- Nephrology Division, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129
| | - Jeannie T Lee
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts 02114; Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115
| | - Peter A Nigrovic
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, Massachusetts 02115
| | - Roy J Soberman
- Nephrology Division, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129.
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8
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Schmider AB, Vaught M, Bauer NC, Elliott HL, Godin MD, Ellis GE, Nigrovic PA, Soberman RJ. The organization of leukotriene biosynthesis on the nuclear envelope revealed by single molecule localization microscopy and computational analyses. PLoS One 2019; 14:e0211943. [PMID: 30735559 PMCID: PMC6368329 DOI: 10.1371/journal.pone.0211943] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 01/24/2019] [Indexed: 12/21/2022] Open
Abstract
The initial steps in the synthesis of leukotrienes are the translocation of 5-lipoxygenase (5-LO) to the nuclear envelope and its subsequent association with its scaffold protein 5-lipoxygenase-activating protein (FLAP). A major gap in our understanding of this process is the knowledge of how the organization of 5-LO and FLAP on the nuclear envelope regulates leukotriene synthesis. We combined single molecule localization microscopy with Clus-DoC cluster analysis, and also a novel unbiased cluster analysis to analyze changes in the relationships between 5-LO and FLAP in response to activation of RBL-2H3 cells to generate leukotriene C4. We identified the time-dependent reorganization of both 5-LO and FLAP into higher-order assemblies or clusters in response to cell activation via the IgE receptor. Clus-DoC analysis identified a subset of these clusters with a high degree of interaction between 5-LO and FLAP that specifically correlates with the time course of LTC4 synthesis, strongly suggesting their role in the initiation of leukotriene biosynthesis.
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Affiliation(s)
- Angela B. Schmider
- Nephrology Division, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States of America
| | - Melissa Vaught
- Nephrology Division, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States of America
| | - Nicholas C. Bauer
- Nephrology Division, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States of America
| | - Hunter L. Elliott
- Image and Data Analysis Core, Department of Cell Biology, Harvard Medical School, Boston, MA, United States of America
| | - Matthew D. Godin
- Nephrology Division, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States of America
| | - Giorgianna E. Ellis
- Nephrology Division, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States of America
| | - Peter A. Nigrovic
- Division of Rheumatology, Immunology and Allergy, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, United States of America
| | - Roy J. Soberman
- Nephrology Division, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States of America
- * E-mail:
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9
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A 5‑lipoxygenase-specific sequence motif impedes enzyme activity and confers dependence on a partner protein. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1864:543-551. [PMID: 30291962 DOI: 10.1016/j.bbalip.2018.09.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 08/31/2018] [Accepted: 09/30/2018] [Indexed: 11/22/2022]
Abstract
Leukotrienes (LT) are lipid mediators of the inflammatory response that play key roles in diseases such as asthma and atherosclerosis. The precursor leukotriene A4 (LTA4) is synthesized from arachidonic acid (AA) by 5‑lipoxygenase (5-LOX), a membrane-associated enzyme, with the help of 5‑lipoxygenase-activating protein (FLAP), a nuclear transmembrane protein. In lipoxygenases the main chain carboxylate of the C-terminus is a ligand for the non-heme iron and thus part of the catalytic center. We investigated the role of a lysine-rich sequence (KKK653-655) 20 amino acids upstream of the C-terminus unique to 5-LOX that might displace the main-chain carboxylate in the iron coordination sphere. A 5-LOX mutant in which KKK653-655 is replaced by ENL was transfected into HEK293 cells in the absence and presence of FLAP. This mutant gave ~20-fold higher 5-LOX product levels in stimulated HEK cells relative to the wild-type 5-LOX. Co-expression of the enzymes with FLAP led to an equalization of 5-LOX products detected, with wild-type 5-LOX product levels increased and those from the mutant enzyme decreased. These data suggest that the KKK motif limits 5-LOX activity and that this attenuated activity must be compensated by the presence of FLAP as a partner protein for effective LT biosynthesis.
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10
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Phospholipase A 2 catalysis and lipid mediator lipidomics. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1864:766-771. [PMID: 30905345 DOI: 10.1016/j.bbalip.2018.08.010] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 08/10/2018] [Accepted: 08/16/2018] [Indexed: 01/09/2023]
Abstract
Phospholipase A2 (PLA2) enzymes are the upstream regulators of the eicosanoid pathway liberating free arachidonic acid from the sn-2 position of membrane phospholipids. Free intracellular arachidonic acid serves as a substrate for the eicosanoid biosynthetic enzymes including cyclooxygenases, lipoxygenases, and cytochrome P450s that lead to inflammation. The Group IVA cytosolic (cPLA2), Group VIA calcium-independent (iPLA2), and Group V secreted (sPLA2) are three well-characterized human enzymes that have been implicated in eicosanoid formation. In this review, we will introduce and summarize the regulation of catalytic activity and cellular localization, structural characteristics, interfacial activation and kinetics, substrate specificity, inhibitor binding and interactions, and the downstream implications for eicosanoid biosynthesis of these three important PLA2 enzymes.
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11
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Abstract
Leukotrienes are powerful immune-regulating lipid mediators with established pathogenic roles in inflammatory allergic diseases of the respiratory tract - in particular, asthma and hay fever. More recent work indicates that these lipids also contribute to low-grade inflammation, a hallmark of cardiovascular, neurodegenerative, and metabolic diseases as well as cancer. Biosynthesis of leukotrienes involves oxidative metabolism of arachidonic acid and proceeds via a set of soluble and membrane enzymes that are primarily expressed by cells of myeloid origin. In activated immune cells, these enzymes assemble at the endoplasmic and perinuclear membrane, constituting a biosynthetic complex. This Review describes recent advances in our understanding of the components of the leukotriene-synthesizing enzyme machinery, emerging opportunities for pharmacological intervention, and the development of new medicines exploiting both antiinflammatory and pro-resolving mechanisms.
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12
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Subramanian BC, Majumdar R, Parent CA. The role of the LTB 4-BLT1 axis in chemotactic gradient sensing and directed leukocyte migration. Semin Immunol 2018; 33:16-29. [PMID: 29042024 DOI: 10.1016/j.smim.2017.07.002] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 06/07/2017] [Accepted: 07/13/2017] [Indexed: 12/11/2022]
Abstract
Directed leukocyte migration is a hallmark of inflammatory immune responses. Leukotrienes are derived from arachidonic acid and represent a class of potent lipid mediators of leukocyte migration. In this review, we summarize the essential steps leading to the production of LTB4 in leukocytes. We discuss the recent findings on the exosomal packaging and transport of LTB4 in the context of chemotactic gradients formation and regulation of leukocyte recruitment. We also discuss the dynamic roles of the LTB4 receptors, BLT1 and BLT2, in mediating chemotactic signaling in leukocytes and contrast them to other structurally related leukotrienes that bind to distinct GPCRs. Finally, we highlight the specific roles of the LTB4-BLT1 axis in mediating signal-relay between chemotaxing neutrophils and its potential contribution to a wide variety of inflammatory conditions including tumor progression and metastasis, where LTB4 is emerging as a key signaling component.
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Affiliation(s)
- Bhagawat C Subramanian
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, NCI, NIH, Bethesda, MD 20892, United States.
| | - Ritankar Majumdar
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, NCI, NIH, Bethesda, MD 20892, United States; Department of Pharmacology, University of Michigan School of Medicine, Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, United States.
| | - Carole A Parent
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, NCI, NIH, Bethesda, MD 20892, United States; Department of Pharmacology, University of Michigan School of Medicine, Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, United States.
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13
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Drug discovery approaches targeting 5-lipoxygenase-activating protein (FLAP) for inhibition of cellular leukotriene biosynthesis. Eur J Med Chem 2017; 153:34-48. [PMID: 28784429 DOI: 10.1016/j.ejmech.2017.07.019] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 06/29/2017] [Accepted: 07/12/2017] [Indexed: 11/23/2022]
Abstract
Leukotrienes are proinflammatory lipid mediators associated with diverse chronic inflammatory diseases such as asthma, COPD, IBD, arthritis, atherosclerosis, dermatitis and cancer. Cellular leukotrienes are produced from arachidonic acid via the 5-lipoxygenase pathway in which the 5-lipoxygenase activating protein, also named as FLAP, plays a critical role by operating as a regulatory protein for efficient transfer of arachidonic acid to 5-lipoxygenase. By blocking leukotriene production, FLAP inhibitors may behave as broad-spectrum leukotriene modulators, which might be of therapeutic use for chronic inflammatory diseases requiring anti-leukotriene therapy. The early development of FLAP inhibitors (i.e. MK-886, MK-591, BAY-X-1005) mostly concentrated on asthma cure, and resulted in promising readouts in preclinical and clinical studies with asthma patients. Following the recent elucidation of the 3D-structure of FLAP, development of new inhibitor chemotypes is highly accelerated, eventually leading to the evolution of many un-drug-like structures into more drug-like entities such as AZD6642 and BI665915 as development candidates. The most clinically advanced FLAP inhibitor to date is GSK2190918 (formerly AM803) that has successfully completed phase II clinical trials in asthmatics. Concluding, although there are no FLAP inhibitors reached to the drug approval phase yet, due to the rising number of indications for anti-LT therapy such as atherosclerosis, FLAP inhibitor development remains a significant research field. FLAP inhibitors reviewed herein are classified into four sub-classes as the first-generation FLAP inhibitors (indole and quinoline derivatives), the second-generation FLAP inhibitors (diaryl-alkanes and biaryl amino-heteroarenes), the benzimidazole-containing FLAP inhibitors and other FLAP inhibitors with polypharmacology for easiness of the reader. Hence, we meticulously summarize how FLAP inhibitors historically developed from scratch to their current advanced state, and leave the reader with a positive view that a FLAP inhibitor might soon reach to the need of patients who may require anti-LT therapy.
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Kuhnert R, Sárosi MB, George S, Lönnecke P, Hofmann B, Steinhilber D, Murganic B, Mijatovic S, Maksimovic-Ivanic D, Hey-Hawkins E. CarbORev-5901: The First Carborane-Based Inhibitor of the 5-Lipoxygenase Pathway. ChemMedChem 2017; 12:1081-1086. [PMID: 28569429 DOI: 10.1002/cmdc.201700309] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2017] [Revised: 05/31/2017] [Indexed: 01/05/2023]
Abstract
The progression of cancer is accelerated by increased proliferation, angiogenesis, and inflammation. These processes are mediated by leukotrienes. Several cancer cell lines overexpress 5-lipoxygenase, an enzyme that converts arachidonic acid into leukotrienes. An early inhibitor of the 5-lipoxygenase pathway is Rev-5901, which, however, lacks in in vivo efficacy, as it is rapidly metabolized. We investigated the introduction of carboranes as highly hydrophobic and metabolically stable pharmacophores into lipoxygenase inhibitors. Carboranes are icosahedral boron clusters that are remarkably stable and used to increase the metabolic stability of unstable pharmaceutics without changing their biological activity. By introduction of meta-carborane into Rev-5901, the first carborane-based inhibitor of the 5-lipoxygenase pathway was obtained. We report the synthesis and inhibitory and cytotoxic behavior of these compounds toward several melanoma and colon cancer cell lines and their related anticancer mechanisms.
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Affiliation(s)
- Robert Kuhnert
- Institut für Anorganische Chemie, Universität Leipzig, Johannisallee 29, 04103, Leipzig, Germany
| | - Menyhárt-Botond Sárosi
- Institut für Anorganische Chemie, Universität Leipzig, Johannisallee 29, 04103, Leipzig, Germany
| | - Sven George
- Institut für Pharmazeutische Chemie, Johann-Wolfgang-Goethe-Universität Frankfurt, Max-von-Laue-Straße 9, 60438, Frankfurt, Germany
| | - Peter Lönnecke
- Institut für Anorganische Chemie, Universität Leipzig, Johannisallee 29, 04103, Leipzig, Germany
| | - Bettina Hofmann
- Institut für Pharmazeutische Chemie, Johann-Wolfgang-Goethe-Universität Frankfurt, Max-von-Laue-Straße 9, 60438, Frankfurt, Germany
| | - Dieter Steinhilber
- Institut für Pharmazeutische Chemie, Johann-Wolfgang-Goethe-Universität Frankfurt, Max-von-Laue-Straße 9, 60438, Frankfurt, Germany
| | - Blagoje Murganic
- Department of Immunology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Bul. despota Stefana 142, 11060, Belgrade, Serbia
| | - Sanja Mijatovic
- Department of Immunology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Bul. despota Stefana 142, 11060, Belgrade, Serbia
| | - Danijela Maksimovic-Ivanic
- Department of Immunology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Bul. despota Stefana 142, 11060, Belgrade, Serbia
| | - Evamarie Hey-Hawkins
- Institut für Anorganische Chemie, Universität Leipzig, Johannisallee 29, 04103, Leipzig, Germany
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Bandeira-Melo C, Paiva LA, Amorim NRT, Weller PF, Bozza PT. EicosaCell: An Imaging-Based Assay to Identify Spatiotemporal Eicosanoid Synthesis. Methods Mol Biol 2017; 1554:127-141. [PMID: 28185186 PMCID: PMC5774667 DOI: 10.1007/978-1-4939-6759-9_6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Eicosanoids are bioactive lipids derived from enzymatic metabolism of arachidonic acid via the cyclooxygenase (COX) and lipoxygenase (LOX) pathways. These lipids are newly formed and nonstorable molecules that have important roles in physiological and pathological processes. The particular interest to determine intracellular compartmentalization of eicosanoid-synthetic machinery has emerged as a key component in the regulation of eicosanoid synthesis and in delineating functional intracellular and extracellular actions of eicosanoids. In this chapter, we discuss the EicosaCell protocol, an assay that enables the intracellular detection and localization of eicosanoid lipid mediator-synthesizing compartments by means of a strategy to covalently cross-link and immobilize eicosanoids at their sites of synthesis followed by immunofluorescent-based localization of the targeted eicosanoid. EicosaCell assays have been successfully used to identify different intracellular compartments of synthesis of prostaglandins and leukotrienes upon cellular activation. This chapter covers basics of EicosaCell assay including its selection of reagents, immunodetection design as well as some troubleshooting recommendations.
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Affiliation(s)
- Christianne Bandeira-Melo
- Laboratório de Inflamação, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
| | - Ligia Almeida Paiva
- Laboratório de Inflamação, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil
| | - Natália R T Amorim
- Laboratório de Inflamação, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Peter F Weller
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Patricia T Bozza
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil.
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Lang L, Dong N, Wu D, Yao X, Lu W, Zhang C, Ouyang P, Zhu J, Tang Y, Wang W, Li J, Huang J. 2-Arylbenzo[b]furan derivatives as potent human lipoxygenase inhibitors. J Enzyme Inhib Med Chem 2016; 31:98-105. [DOI: 10.1080/14756366.2016.1220376] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Affiliation(s)
- Li Lang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China,
| | - Ningning Dong
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China,
| | - Deyan Wu
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China,
| | - Xue Yao
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China,
| | - Weiqiang Lu
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China, and
| | - Chen Zhang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China,
| | - Ping Ouyang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China,
| | - Jin Zhu
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China,
| | - Yun Tang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China,
| | - Wei Wang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China,
- Department of Chemistry & Chemical Biology, University of New Mexico, Albuquerque, NM, USA
| | - Jian Li
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China,
| | - Jin Huang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China,
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Gerstmeier J, Newcomer ME, Dennhardt S, Romp E, Fischer J, Werz O, Garscha U. 5-Lipoxygenase-activating protein rescues activity of 5-lipoxygenase mutations that delay nuclear membrane association and disrupt product formation. FASEB J 2016; 30:1892-900. [PMID: 26842853 DOI: 10.1096/fj.201500210r] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 01/17/2016] [Indexed: 12/26/2022]
Abstract
Leukotrienes (LTs) are proinflammatory lipid mediators formed from arachidonic acid in a 2-step reaction catalyzed by 5-lipoxygenase (5-LOX) requiring the formation of 5-HPETE [5(S)-hydroperoxy-6-trans-8,11,14-cis-eicosatetraenoic acid] and its subsequent transformation to LTA4 5-LOX is thought to receive arachidonic acid from the nuclear membrane-embedded 5-LOX-activating protein (FLAP). The crystal structure of 5-LOX revealed an active site concealed by F177 and Y181 (FY cork). We examined the influence of the FY cork on 5-LOX activity and membrane binding in HEK293 cells in the absence and presence of FLAP. Uncapping the 5-LOX active site by mutation of F177 and/or Y181 to alanine (5-LOX-F177A, 5-LOX-Y181A, 5-LOX-F177/Y181A) resulted in delayed and diminished 5-LOX membrane association in A23187-stimulated cells. For 5-LOX-F177A and 5-LOX-F177/Y181A, formation of 5-LOX products was dramatically reduced relative to 5-LOX-wild type (wt). Strikingly, coexpression of FLAP in A23187-activated HEK293 cells effectively restored formation of 5-H(p)ETE (5-hydroxy- and 5-peroxy-6-trans-8,11,14-cis-eicosatetraenoic acid) by these same 5-LOX mutants (≈60-70% 5-LOX-wt levels) but not of LTA4 hydrolysis products. Yet 5-LOX-Y181A generated 5-H(p)ETE at levels comparable to 5-LOX-wt but reduced LTA4 hydrolysis products. Coexpression of FLAP partially restored LTA4 hydrolysis product formation by 5-LOX-Y181A. Together, the data suggest that the concealed FY cork impacts membrane association and that FLAP may help shield an uncapped active site.-Gerstmeier, J., Newcomer, M. E., Dennhardt, S., Romp, E., Fischer, J., Werz, O., Garscha, U. 5-Lipoxygenase-activating protein rescues activity of 5-lipoxygenase mutations that delay nuclear membrane association and disrupt product formation.
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Affiliation(s)
- Jana Gerstmeier
- Department of Pharmaceutical and Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, Germany; and
| | - Marcia E Newcomer
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Sophie Dennhardt
- Department of Pharmaceutical and Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, Germany; and
| | - Erik Romp
- Department of Pharmaceutical and Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, Germany; and
| | - Jana Fischer
- Department of Pharmaceutical and Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, Germany; and
| | - Oliver Werz
- Department of Pharmaceutical and Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, Germany; and
| | - Ulrike Garscha
- Department of Pharmaceutical and Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, Germany; and
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The Lipoxygenases: Their Regulation and Implication in Alzheimer's Disease. Neurochem Res 2015; 41:243-57. [PMID: 26677076 PMCID: PMC4773476 DOI: 10.1007/s11064-015-1776-x] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 11/06/2015] [Accepted: 11/14/2015] [Indexed: 02/03/2023]
Abstract
Inflammatory processes and alterations of lipid metabolism play a crucial role in Alzheimer’s disease (AD) and other neurodegenerative disorders. Polyunsaturated fatty acids (PUFA) metabolism impaired by cyclooxygenases (COX-1, COX-2), which are responsible for formation of several eicosanoids, and by lipoxygenases (LOXs) that catalyze the addition of oxygen to linolenic, arachidonic (AA), and docosahexaenoic acids (DHA) and other PUFA leading to formation of bioactive lipids, significantly affects the course of neurodegenerative diseases. Among several isoforms, 5-LOX and 12/15-LOX are especially important in neuroinflammation/neurodegeneration. These two LOXs are regulated by substrate concentration and availability, and by phosphorylation/dephosphorylation through protein kinases PKA, PKC and MAP-kinases, including ERK1/ERK2 and p38. The protein/protein interaction also is involved in the mechanism of 5-LOX regulation through FLAP protein and coactosin-like protein. Moreover, non-heme iron and calcium ions are potent regulators of LOXs. The enzyme activity significantly depends on the cell redox state and is differently regulated by various signaling pathways. 5-LOX and 12/15-LOX convert linolenic acid, AA, and DHA into several bioactive compounds e.g. hydroperoxyeicosatetraenoic acids (5-HPETE, 12S-HPETE, 15S-HPETE), which are reduced to corresponding HETE compounds. These enzymes synthesize several bioactive lipids, e.g. leucotrienes, lipoxins, hepoxilins and docosahexaenoids. 15-LOX is responsible for DHA metabolism into neuroprotectin D1 (NPD1) with significant antiapoptotic properties which is down-regulated in AD. In this review, the regulation and impact of 5-LOX and 12/15-LOX in the pathomechanism of AD is discussed. Moreover, we describe the role of several products of LOXs, which may have significant pro- or anti-inflammatory activity in AD, and the cytoprotective effects of LOX inhibitors.
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Kalinina EV, Chernov NN, Novichkova MD. Role of glutathione, glutathione transferase, and glutaredoxin in regulation of redox-dependent processes. BIOCHEMISTRY (MOSCOW) 2015; 79:1562-83. [PMID: 25749165 DOI: 10.1134/s0006297914130082] [Citation(s) in RCA: 110] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Over the last decade fundamentally new features have been revealed for the participation of glutathione and glutathione-dependent enzymes (glutathione transferase and glutaredoxin) in cell proliferation, apoptosis, protein folding, and cell signaling. Reduced glutathione (GSH) plays an important role in maintaining cellular redox status by participating in thiol-disulfide exchange, which regulates a number of cell functions including gene expression and the activity of individual enzymes and enzyme systems. Maintaining optimum GSH/GSSG ratio is essential to cell viability. Decrease in the ratio can serve as an indicator of damage to the cell redox status and of changes in redox-dependent gene regulation. Disturbance of intracellular GSH balance is observed in a number of pathologies including cancer. Consequences of inappropriate GSH/GSSG ratio include significant changes in the mechanism of cellular redox-dependent signaling controlled both nonenzymatically and enzymatically with the participation of isoforms of glutathione transferase and glutaredoxin. This review summarizes recent data on the role of glutathione, glutathione transferase, and glutaredoxin in the regulation of cellular redox-dependent processes.
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Affiliation(s)
- E V Kalinina
- Peoples' Friendship University of Russia, Moscow, 117198, Russia.
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20
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Leslie CC. Cytosolic phospholipase A₂: physiological function and role in disease. J Lipid Res 2015; 56:1386-402. [PMID: 25838312 DOI: 10.1194/jlr.r057588] [Citation(s) in RCA: 260] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2015] [Indexed: 02/06/2023] Open
Abstract
The group IV phospholipase A2 (PLA2) family is comprised of six intracellular enzymes (GIVA, -B, -C, -D, -E, and -F) commonly referred to as cytosolic PLA2 (cPLA2)α, -β, -γ, -δ, -ε, and -ζ. They contain a Ser-Asp catalytic dyad and all except cPLA2γ have a C2 domain, but differences in their catalytic activities and subcellular localization suggest unique regulation and function. With the exception of cPLA2α, the focus of this review, little is known about the in vivo function of group IV enzymes. cPLA2α catalyzes the hydrolysis of phospholipids to arachidonic acid and lysophospholipids that are precursors of numerous bioactive lipids. The regulation of cPLA2α is complex, involving transcriptional and posttranslational processes, particularly increases in calcium and phosphorylation. cPLA2α is a highly conserved widely expressed enzyme that promotes lipid mediator production in human and rodent cells from a variety of tissues. The diverse bioactive lipids produced as a result of cPLA2α activation regulate normal physiological processes and disease pathogenesis in many organ systems, as shown using cPLA2α KO mice. However, humans recently identified with cPLA2α deficiency exhibit more pronounced effects on health than observed in mice lacking cPLA2α, indicating that much remains to be learned about this interesting enzyme.
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Affiliation(s)
- Christina C Leslie
- Department of Pediatrics, National Jewish Health, Denver, CO 80206; and Departments of Pathology and Pharmacology, University of Colorado Denver, Aurora, CO 80045
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Li ZY, Jiang WY, Cui ZJ. An essential role of NAD(P)H oxidase 2 in UVA-induced calcium oscillations in mast cells. Photochem Photobiol Sci 2015; 14:414-28. [PMID: 25460548 DOI: 10.1039/c4pp00304g] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Solar UVA radiation (320-400 nm) is known to have immunomodulatory effects, but the detailed mechanisms involved are not fully elucidated. UVA irradiation has been shown to induce calcium oscillations in rat peritoneal mast cells due to NAD(P)H oxidase (NOX) activation, but the specific NOX isoforms have not been identified. In the present work effects of UVA irradiation were investigated in isolated rat peritoneal mast cells, in cultured rat mast cell line RBL-2H3, and in mouse bone marrow-derived mast cells (BMMC). It was found that UVA irradiation by alternate 340/380 nm (3.2-5.6 μW cm(-2)) or by LED (380 nm, 80 μW cm(-2)) induced calcium oscillations in isolated rat peritoneal mast cells, in RBL-2H3, and in BMMC. Such UVA-induced calcium oscillations resembled closely those induced by surface IgE receptor (FcεRI) activation. It was found that RBL-2H3 expressed high levels of gp91(phox) (NOX2), p22(phox), p67(phox), p47(phox), p40(phox), Rac1, Rac2, moderate levels of DUOX2, but did not express NOX1, NOX3, NOX4, or DUOX1. The specific cellular localizations of gp91(phox) (NOX2), p22(phox), p47(phox), p67(phox), p40(phox) and Rac1/2 were confirmed by immunocytochemistry. UVA-induced reactive oxygen species (ROS) production in RBL-2H3 was completely suppressed by the NOX inhibitor diphenyleneiodonium chloride (DPI) or by the antioxidant N-acetyl-l-cysteine (NAC). siRNA suppression of gp91(phox) (NOX2), p22(phox) and p47(phox) expression inhibited markedly UVA-induced calcium oscillations, ROS and IL-6/LTC4 production in RBL-2H3. Taken together these data indicate that NOX2 plays an essential role in UVA irradiation-induced calcium oscillations, ROS and mediator production in mast cells.
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Affiliation(s)
- Zhi Ying Li
- Institute of Cell Biology, Beijing Normal University, Beijing 100875, China.
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Rådmark O, Werz O, Steinhilber D, Samuelsson B. 5-Lipoxygenase, a key enzyme for leukotriene biosynthesis in health and disease. Biochim Biophys Acta Mol Cell Biol Lipids 2014; 1851:331-9. [PMID: 25152163 DOI: 10.1016/j.bbalip.2014.08.012] [Citation(s) in RCA: 326] [Impact Index Per Article: 32.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 08/13/2014] [Accepted: 08/14/2014] [Indexed: 12/21/2022]
Abstract
5-Lipoxygenase (5-LOX) catalyzes two steps in the biosynthesis of leukotrienes (LTs), lipid mediators of inflammation derived from arachidonic acid. In this review we focus on 5-LOX biochemistry including 5-LOX interacting proteins and regulation of enzyme activity. LTs function in normal host defense, and have roles in many disease states where acute or chronic inflammation is part of the pathophysiology, as briefly summarized at the end of this chapter. This article is part of a Special Issue entitled "Oxygenated metabolism of PUFA: analysis and biological relevance".
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Affiliation(s)
- Olof Rådmark
- Dept of Medical Biochemistry and Biophysics, Div. of Chemistry II, Karolinska Institutet, Sweden
| | - Oliver Werz
- Chair of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, University Jena, Germany
| | - Dieter Steinhilber
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Germany
| | - Bengt Samuelsson
- Dept of Medical Biochemistry and Biophysics, Div. of Chemistry II, Karolinska Institutet, Sweden
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Lu Y, Li X, Park YN, Kwon O, Piao D, Chang YC, Kim CH, Lee E, Son JK, Chang HW. Britanin Suppresses IgE/Ag-Induced Mast Cell Activation by Inhibiting the Syk Pathway. Biomol Ther (Seoul) 2014; 22:193-9. [PMID: 25009699 PMCID: PMC4060075 DOI: 10.4062/biomolther.2014.038] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Revised: 05/01/2014] [Accepted: 05/07/2014] [Indexed: 11/16/2022] Open
Abstract
The aim of this study was to determine whether britanin, isolated from the flowers of Inula japonica (Inulae Flos), modulates the generation of allergic inflammatory mediators in activated mast cells. To understand the biological activity of britanin, the authors investigated its effects on the generation of prostaglandin D2 (PGD2), leukotriene C4 (LTC4), and degranulation in IgE/Ag-induced bone marrow-derived mast cells (BMMCs). Britanin dose dependently inhibited degranulation and the generations of PGD2 and LTC4 in BMMCs. Biochemical analyses of IgE/Ag-mediated signaling pathways demonstrated that britanin suppressed the phosphorylation of Syk kinase and multiple downstream signaling processes, including phospholipase Cγ1 (PLCγ1)-mediated calcium influx, the activation of mitogen-activated protein kinases (MAPKs; extracellular signal-regulated kinase 1/2, c-Jun NH2-terminal kinase and p38), and the nuclear factor-κB (NF-κB) pathway. Taken together, the findings of this study suggest britanin suppresses degranulation and eicosanoid generation by inhibiting the Syk-dependent pathway and britanin might be useful for the treatment of allergic inflammatory diseases.
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Affiliation(s)
- Yue Lu
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China ; College of Pharmacy, Yeungnam University, Gyeongsan 712-749
| | - Xian Li
- College of Pharmacy, Yeungnam University, Gyeongsan 712-749
| | - Young Na Park
- College of Pharmacy, Yeungnam University, Gyeongsan 712-749
| | - Okyun Kwon
- College of Pharmacy, Yeungnam University, Gyeongsan 712-749
| | - Donggen Piao
- College of Pharmacy, Yeungnam University, Gyeongsan 712-749
| | - Young-Chae Chang
- Department of Pathology, Catholic University of Daegu School of Medicine, Daegu 705-718
| | - Cheorl-Ho Kim
- Department of Biological Science, Sungkyunkwan University, Suwon 440-746
| | - Eunkyung Lee
- Research and Development Division, Korean Promotion Institute for Traditional Medicine Industry, Gyeongsan 712-210, Republic of Korea
| | - Jong Keun Son
- College of Pharmacy, Yeungnam University, Gyeongsan 712-749
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Gerstmeier J, Weinigel C, Barz D, Werz O, Garscha U. An experimental cell-based model for studying the cell biology and molecular pharmacology of 5-lipoxygenase-activating protein in leukotriene biosynthesis. Biochim Biophys Acta Gen Subj 2014; 1840:2961-9. [PMID: 24905297 DOI: 10.1016/j.bbagen.2014.05.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 05/09/2014] [Accepted: 05/25/2014] [Indexed: 12/13/2022]
Abstract
BACKGROUND Subcellular distribution of 5-lipoxygenase (5-LO) to the perinuclear region and interaction with the 5-LO-activating protein (FLAP) are assumed as key steps in leukotriene biosynthesis and are prone to FLAP antagonists. METHODS FLAP and/or 5-LO were stably expressed in HEK293 cells, 5-LO products were analyzed by HPLC, and 5-LO and FLAP subcellular localization was visualized by immunofluorescence microscopy. RESULTS 5-LO and FLAP were stably expressed in HEK293 cells, and upon Ca(2+)-ionophore A23187 stimulation exogenous AA was efficiently transformed into the 5-LO products 5-hydro(pero)xyeicosatetraenoic acid (5-H(p)ETE) and the trans-isomers of LTB4. A23187 stimulation caused 5-LO accumulation at the nuclear membrane only when FLAP was co-expressed. Unexpectedly, A23187 stimulation of HEK cells expressing 5-LO and FLAP without exogenous AA failed in 5-LO product synthesis. HEK cells liberated AA in response to A23187, and transfected HEK cells expressing 12-LO generated 12-HETE after A23187 challenge from endogenous AA. FLAP co-expression increased 5-LO product formation in A23187-stimulated cells at low AA concentrations. Only in cells expressing FLAP and 5-LO, the FLAP antagonist MK886 blocked FLAP-mediated increase in 5-LO product formation, and prevented 5-LO nuclear membrane translocation and co-localization with FLAP. CONCLUSION The cellular biosynthesis of 5-LO products from endogenously derived substrate requires not only functional 5-LO/FLAP co-localization but also additional prerequisites which are dispensable when exogenous AA is supplied; identification of these determinants is challenging. GENERAL SIGNIFICANCE We present a cell model to study the role of FLAP as 5-LO interacting protein in LT biosynthesis in intact cells and for characterization of putative FLAP antagonists.
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Affiliation(s)
- Jana Gerstmeier
- Chair of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University, Germany
| | - Christina Weinigel
- Institute of Transfusion Medicine, Jena University Hospital, 07743 Jena, Germany
| | - Dagmar Barz
- Institute of Transfusion Medicine, Jena University Hospital, 07743 Jena, Germany
| | - Oliver Werz
- Chair of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University, Germany
| | - Ulrike Garscha
- Chair of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University, Germany
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Ye F, Liu NN, Zheng YQ, Zhang WJ, Wang CM, Xu Y, Den XL, Wang J. Three polymorphisms of ALOX5AP and risk of ischemic stroke in Chinese: Evidence from a meta-analysis. J Neurol Sci 2014; 336:93-8. [DOI: 10.1016/j.jns.2013.10.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2013] [Revised: 10/06/2013] [Accepted: 10/07/2013] [Indexed: 11/28/2022]
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Chu J, Lauretti E, Meco A, Praticò D. FLAP pharmacological blockade modulates metabolism of endogenous tau in vivo . Transl Psychiatry 2013; 3:e333. [PMID: 24301651 PMCID: PMC4030325 DOI: 10.1038/tp.2013.106] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 09/10/2013] [Accepted: 10/21/2013] [Indexed: 01/28/2023] Open
Abstract
FLAP (5-lipoxygenase-activating protein) is a protein widely distributed within the central nervous system whose function is to regulate the activation of the 5-Lipoxygenase enzyme. Although previous works show that pharmacological blockade of FLAP improve the amyloidotic phenotype of the Tg2576, its contribution to tau pathology remains to be investigated. In the present paper, we studied the effect of FLAP pharmacological inhibition on the metabolism of endogenous tau in these mice. Total tau levels in the brains of mice receiving MK-591, a selective and specific FLAP inhibitor, were not changed when compared with controls. By contrast, treated animals had a significant reduction of tau phosphorylation at specific sites: Ser396; Ser396/Ser404; and Thr 231/Ser 235. This reduction was associated with a significant decrease in the activity of glycogen synthase kinase-3 beta, but not other kinases. In addition, MK-591-treated mice had a significant increase in the post-synaptic density protein-95 and the dendritic protein microtubule-associated protein 2. These data establish a novel functional role for FLAP in the metabolism of tau, and together with its known Aβ modulatory effect they suggest that its pharmacological inhibition could represent a novel therapeutic opportunity for Alzheimer's disease.
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Affiliation(s)
- J Chu
- Department of Pharmacology and Center for Translational Medicine, Temple University School of Medicine, Philadelphia, PA, USA
| | - E Lauretti
- Department of Pharmacology and Center for Translational Medicine, Temple University School of Medicine, Philadelphia, PA, USA
| | - A Di Meco
- Department of Pharmacology and Center for Translational Medicine, Temple University School of Medicine, Philadelphia, PA, USA
| | - D Praticò
- Department of Pharmacology and Center for Translational Medicine, Temple University School of Medicine, Philadelphia, PA, USA,Department of Pharmacology and Center for Translational Medicine, Temple University School of Medicine, 3500 North Broad Street, MERB, 947, Philadelphia, PA 19140, USA. E-mail:
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Chen YP, Zhang ZY, Li YP, Li D, Huang SL, Gu LQ, Xu J, Huang ZS. Syntheses and evaluation of novel isoliquiritigenin derivatives as potential dual inhibitors for amyloid-beta aggregation and 5-lipoxygenase. Eur J Med Chem 2013; 66:22-31. [PMID: 23786711 DOI: 10.1016/j.ejmech.2013.05.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 05/12/2013] [Accepted: 05/13/2013] [Indexed: 12/21/2022]
Abstract
A series of new isoliquiritigenin (ISL) derivatives were synthesized and evaluated as dual inhibitors for amyloid-beta (Aβ) aggregation and 5-lipoxygenase (5-LO). It was found that all these synthetic compounds inhibited Aβ (1-42) aggregation effectively with their IC₅₀ values ranged from 2.2 ± 1.5 μM to 23.8 ± 2.0 μM. These derivatives also showed inhibitory activity to 5-LO with their IC50 values ranged from 6.1 ± 0.1 μM to 35.9 ± 0.3 μM. Their structure-activity relationships (SAR) and mechanisms of inhibitions were studied. This study provided potentially important information for further development of ISL derivatives as multifunctional agents for Alzheimer's disease (AD) treatment.
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Affiliation(s)
- Yi-Ping Chen
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, People's Republic of China
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Aparoy P, Reddy KK, Reddanna P. Structure and ligand based drug design strategies in the development of novel 5- LOX inhibitors. Curr Med Chem 2012; 19:3763-78. [PMID: 22680930 PMCID: PMC3480706 DOI: 10.2174/092986712801661112] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Revised: 01/30/2012] [Accepted: 02/07/2012] [Indexed: 12/26/2022]
Abstract
Lipoxygenases (LOXs) are non-heme iron containing dioxygenases involved in the oxygenation of polyunsaturated fatty acids (PUFAs) such as arachidonic acid (AA). Depending on the position of insertion of oxygen, LOXs are classified into 5-, 8-, 9-, 12- and 15-LOX. Among these, 5-LOX is the most predominant isoform associated with the formation of 5-hydroperoxyeicosatetraenoic acid (5-HpETE), the precursor of non-peptido (LTB4) and peptido (LTC4, LTD4, and LTE4) leukotrienes. LTs are involved in inflammatory and allergic diseases like asthma, ulcerative colitis, rhinitis and also in cancer. Consequently 5-LOX has become target for the development of therapeutic molecules for treatment of various inflammatory disorders. Zileuton is one such inhibitor of 5-LOX approved for the treatment of asthma. In the recent times, computer aided drug design (CADD) strategies have been applied successfully in drug development processes. A comprehensive review on structure based drug design strategies in the development of novel 5-LOX inhibitors is presented in this article. Since the crystal structure of 5-LOX has been recently solved, efforts to develop 5-LOX inhibitors have mostly relied on ligand based rational approaches. The present review provides a comprehensive survey on these strategies in the development of 5-LOX inhibitors.
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Bair AM, Turman MV, Vaine CA, Panettieri RA, Soberman RJ. The nuclear membrane leukotriene synthetic complex is a signal integrator and transducer. Mol Biol Cell 2012; 23:4456-64. [PMID: 23015755 PMCID: PMC3496618 DOI: 10.1091/mbc.e12-06-0489] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Leukotrienes are bioactive signaling molecules derived from arachidonic acid that initiate and amplify innate immunity. A single structure, the leukotriene synthetic complex, on the nuclear membrane of neutrophils integrates and transduces extracellular signals to generate the chemotactic lipid LTB4. Leukotrienes (LTs) are lipid-signaling molecules derived from arachidonic acid (AA) that initiate and amplify inflammation. To initiate LT formation, the 5-lipoxygenase (5-LO) enzyme translocates to nuclear membranes, where it associates with its scaffold protein, 5-lipoxygenase–activating protein (FLAP), to form the core of the multiprotein LT synthetic complex. FLAP is considered to function by binding free AA and facilitating its use as a substrate by 5-LO to form the initial LT, LTA4. We used a combination of fluorescence lifetime imaging microscopy, cell biology, and biochemistry to identify discrete AA-dependent and AA-independent steps that occur on nuclear membranes to control the assembly of the LT synthetic complex in polymorphonuclear leukocytes. The association of AA with FLAP changes the configuration of the scaffold protein, enhances recruitment of membrane-associated 5-LO to form complexes with FLAP, and controls the closeness of this association. Granulocyte monocyte colony–stimulating factor provides a second AA-independent signal that controls the closeness of 5-LO and FLAP within complexes but not the number of complexes that are assembled. Our results demonstrate that the LT synthetic complex is a signal integrator that transduces extracellular signals to modulate the interaction of 5-LO and FLAP.
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Affiliation(s)
- Angela M Bair
- Renal Unit, Department of Medicine, Massachusetts General Hospital, Charlestown, MA 02129, USA
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Chu J, Praticò D. Involvement of 5-lipoxygenase activating protein in the amyloidotic phenotype of an Alzheimer's disease mouse model. J Neuroinflammation 2012; 9:127. [PMID: 22697885 PMCID: PMC3425138 DOI: 10.1186/1742-2094-9-127] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Accepted: 03/27/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The 5-lipoxygenase enzyme is widely distributed within the central nervous system and its activity is regulated by the presence and availability of another protein, called 5-lipoxygenase activating protein. While previous works have shown that 5-lipoxygenase is involved in the pathogenesis of Alzheimer's disease, no data are available on the role that 5-lipoxygenase activating protein plays in Alzheimer's disease. METHODS In the present paper, we studied the effect of pharmacologic inhibition of 5-lipoxygenase activating protein on the amyloidotic phenotype of Tg2576 mice. RESULTS Amyloid β peptide (Aβ) deposition in the brains of mice receiving MK-591, a selective and specific 5-lipoxygenase activating protein inhibitor, was significantly reduced when compared with controls. This reduction was associated with a similar decrease in brain Aβ peptides levels. MK-591 treatment did not induce any change in the steady-state levels of amyloid-β precursor protein, β-site amyloid precursor protein cleaving enzyme 1 or disintegrin and metalloproteinase domain-containing protein 10. By contrast, it resulted in a significant reduction of the γ-secretase complex, at the protein and message level. Furthermore, in vitro studies confirmed that MK-591 prevents Aβ formation by modulating γ-secretase complex levels without affecting Notch signaling. CONCLUSIONS These data establish a novel functional role for 5-lipoxygenase activating protein in the pathogenesis of Alzheimer's disease-like amyloidosis, and suggest that its pharmacological inhibition could provide a novel therapeutic opportunity for Alzheimer's disease.
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Affiliation(s)
- Jin Chu
- Center for Translational Medicine, Department of Pharmacology, Temple University School of Medicine, 3420 North Broad Street MRB, 706A, Philadelphia, PA 19140, USA
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Abstract
Ly6G is a glycosylphosphatidylinositol (GPI)-anchored protein of unknown function that is commonly targeted to induce experimental neutrophil depletion in mice. In the present study, we found that doses of anti-Ly6G Abs too low to produce sustained neutropenia remained capable of inhibiting experimental arthritis, leaving joint tissues free of infiltrating neutrophils. Thioglycollate-stimulated peritonitis was also attenuated. No alteration in neutrophil apoptosis was observed, implicating impaired recruitment. Indeed, Ly6G ligation abrogated neutrophil migration toward LTB(4) and other chemoattractants in a transwell system. Exploring the basis for this blockade, we identified colocalization of Ly6G and β2-integrins by confocal microscopy and confirmed close association by both coimmunoprecipitation and fluorescence lifetime imaging microscopy. Anti-Ly6G Ab impaired surface expression of β2-integrins in LTB(4)-stimulated neutrophils and mimicked CD11a blockade in inhibiting both ICAM-1 binding and firm adhesion to activated endothelium under flow conditions. Correspondingly, migration of β2-integrin-deficient neutrophils was no longer inhibited by anti-Ly6G. These results demonstrate that experimental targeting of Ly6G has functional effects on the neutrophil population and identify a previously unappreciated role for Ly6G as a modulator of neutrophil migration to sites of inflammation via a β2-integrin-dependent mechanism.
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Ferguson AD. Structure-based drug design on membrane protein targets: human integral membrane protein 5-lipoxygenase-activating protein. Methods Mol Biol 2012; 841:267-290. [PMID: 22222457 DOI: 10.1007/978-1-61779-520-6_12] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Leukotrienes are biologically active lipid metabolites of arachidonic acid that are involved in inflammation and play a significant role in respiratory and cardiovascular disease. The integral nuclear membrane protein 5-lipoxygenase-activating protein (FLAP) is essential for leukotriene biosynthesis in response to cellular activation. The crystal structures of human FLAP with two inhibitors were recently determined. Inhibitors are bound within the lipid-exposed portion of FLAP, and the unexpected location of the inhibitor-binding site suggests a transport mechanism for arachidonic acid and provides functional insights into leukotriene biosynthesis. This chapter describes how this human integral membrane crystal structure was solved by pushing the limits of low-resolution structure determination and refinement, demonstrating how a low-resolution structure can impact biology and chemistry, and discusses future opportunities for structure-based drug design for this therapeutic target.
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Bozza PT, Bakker-Abreu I, Navarro-Xavier RA, Bandeira-Melo C. Lipid body function in eicosanoid synthesis: an update. Prostaglandins Leukot Essent Fatty Acids 2011; 85:205-13. [PMID: 21565480 DOI: 10.1016/j.plefa.2011.04.020] [Citation(s) in RCA: 135] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Eicosanoids (prostaglandins, leukotrienes and lipoxins) are signaling lipids derived from arachidonic acid metabolism that have important roles in physiological and pathological processes. Lately, intracellular compartmentalization of eicosanoid-synthetic machinery has emerged as a key component in the regulation of eicosanoid synthesis and functions. Over the past years substantial progresses have been made demonstrating that precursors and enzymes involved in eicosanoid synthesis localize at lipid bodies (also known as lipid droplets) and lipid bodies are distinct sites for eicosanoid generation. Here we will review the current knowledge on the functions of lipid bodies as specialized intracellular sites of compartmentalization of signaling with major roles in eicosanoid formation within cells engaged in inflammatory, infectious and neoplastic process.
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Affiliation(s)
- Patricia T Bozza
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, FIOCRUZ, Brazil.
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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: 591] [Impact Index Per Article: 45.5] [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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Yang HJ, Youn H, Seong KM, Yun YJ, Kim W, Kim YH, Lee JY, Kim CS, Jin YW, Youn B. Psoralidin, a dual inhibitor of COX-2 and 5-LOX, regulates ionizing radiation (IR)-induced pulmonary inflammation. Biochem Pharmacol 2011; 82:524-34. [DOI: 10.1016/j.bcp.2011.05.027] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2011] [Revised: 05/23/2011] [Accepted: 05/24/2011] [Indexed: 11/28/2022]
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Hutchinson JL, Rajagopal SP, Sales KJ, Jabbour HN. Molecular regulators of resolution of inflammation: potential therapeutic targets in the reproductive system. Reproduction 2011; 142:15-28. [DOI: 10.1530/rep-11-0069] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Inflammatory processes are central to reproductive events including ovulation, menstruation, implantation and labour, while inflammatory dysregulation is a feature of numerous reproductive pathologies. In recent years, there has been much research into the endogenous mechanisms by which inflammatory reactions are terminated and tissue homoeostasis is restored, a process termed resolution. The identification and characterisation of naturally occurring pro-resolution mediators including lipoxins and annexin A1 has prompted a shift in the field of anti-inflammation whereby resolution is now observed as an active process, triggered as part of a normal inflammatory response. This review will address the process of resolution, discuss available evidence for expression of pro-resolution factors in the reproductive tract and explore possible roles for resolution in physiological reproductive processes and associated pathologies.
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Kumar NS, Braun MP, Chaudhary AG, Young RN. Synthesis of a tritium-labeled photo-affinity probe based on an atypical leukotriene biosynthesis inhibitor. J Labelled Comp Radiopharm 2011. [DOI: 10.1002/jlcr.1804] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Bandeira-Melo C, Weller PF, Bozza PT. EicosaCell - an immunofluorescent-based assay to localize newly synthesized eicosanoid lipid mediators at intracellular sites. Methods Mol Biol 2011; 689:163-181. [PMID: 21153792 PMCID: PMC3679533 DOI: 10.1007/978-1-60761-950-5_10] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Eicosanoids (prostaglandins, leukotrienes and lipoxins) are a family of signaling lipids derived from arachidonic acid that have important roles in physiological and pathological processes. Over the past years, it has been established that successful eicosanoid production is not merely determined by arachidonic acid and eicosanoid-forming enzymes availability, but requires sequential interactions between specific biosynthetic proteins acting in cascade and may involve very unique spatial interactions. Direct assessment of specific subcellular locales of eicosanoid synthesis has been elusive, as those lipid mediators are newly formed, not stored and often rapidly released upon cell stimulation. In this chapter, we discuss the EicosaCell protocol for intracellular detection of eicosanoid-synthesizing compartments by means of a strategy to covalently cross-link and immobilize the lipid mediators at their sites of synthesis followed by immunofluorescent-based localization of the targeted eicosanoid.
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Affiliation(s)
- Christianne Bandeira-Melo
- Laboratory of Inflammation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
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Identifying intracellular sites of eicosanoid lipid mediator synthesis with EicosaCell assays. Methods Mol Biol 2011; 717:277-89. [PMID: 21370037 DOI: 10.1007/978-1-61779-024-9_16] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Eicosanoids, arachidonic acid-derived signaling lipid mediators, are newly formed and nonstorable molecules that have important roles in physiological and pathological processes. EicosaCell is a microscopic assay that enables the intracellular detection and localization of eicosanoid lipid mediator-synthesizing compartments by means of a strategy to covalently cross-link and immobilize eicosanoids at their sites of synthesis followed by immunofluorescent-based localization of the targeted eicosanoid. EicosaCell is a versatile assay which allows analyses of different types of cell preparations, such as cells isolated from humans or harvested cells from in vivo models of inflammation and adherent or suspension cells stimulated in vitro. EicosaCell assays have been successfully used to identify different intracellular compartments of synthesis of prostaglandins and leukotrienes upon cellular activation. This is of particular interest given that over the past decade intracellular compartmentalization of eicosanoid-synthetic machinery has emerged both as a key component in the regulation of eicosanoid synthesis and in delineating functional intracellular and extracellular actions of eicosanoids. This review covers basics of EicosaCell assay including its selection of reagents, immunodetection design as well as some troubleshooting recommendations.
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Esser J, Gehrmann U, D'Alexandri FL, Hidalgo-Estévez AM, Wheelock CE, Scheynius A, Gabrielsson S, Rådmark O. Exosomes from human macrophages and dendritic cells contain enzymes for leukotriene biosynthesis and promote granulocyte migration. J Allergy Clin Immunol 2010; 126:1032-40, 1040.e1-4. [PMID: 20728205 DOI: 10.1016/j.jaci.2010.06.039] [Citation(s) in RCA: 178] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Revised: 06/22/2010] [Accepted: 06/25/2010] [Indexed: 01/06/2023]
Abstract
BACKGROUND Leukotrienes (LTs) are potent proinflammatory lipid mediators with key roles in the pathogenesis of asthma and inflammation. Recently, nanovesicles (exosomes), released from macrophages and dendritic cells (DCs), have become increasingly appreciated as messengers in immunity. OBJECTIVE We investigated whether exosomes from human macrophages, DCs, and plasma contain enzymes for LT biosynthesis and studied potential roles for exosomes in transcellular LT metabolism and granulocyte chemotaxis. METHODS The presence of LT pathway enzymes and LT biosynthesis in exosomes and cells was analyzed by Western blot, immunoelectron microscopy, and enzyme activity assays. Surface marker expression was evaluated by flow cytometry, and granulocyte migration was assessed in a multiwell chemotaxis system. RESULTS Exosomes from macrophages and DCs contain functional enzymes for LT biosynthesis. After incubation of intact cells with the LT biosynthesis intermediate LTA(4), LTB(4) was the major product of macrophages, whereas DCs primarily formed LTC(4). However, in exosomes from both cell types, LTC(4) was the predominant LTA(4) metabolite. Exosomal LTC(4) formation (per milligram protein) exceeded that of cells. In macrophages and DCs, TGF-β1 upregulated LTA(4) hydrolase along with increased LTB(4) formation also in the exosomes. Moreover, TGF-β1 modified the expression of surface marker proteins on cells and exosomes and reduced the exosome yield from macrophages. On Ca(2+)-ionophore and arachidonic acid stimulation, exosomes produced chemotactic eicosanoids and induced granulocyte migration. Interestingly, active LTA(4) hydrolase and LTC(4) synthase were present also in exosomes from human plasma. CONCLUSION Our findings indicate that exosomes can contribute to inflammation by participation in LT biosynthesis and granulocyte recruitment.
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Affiliation(s)
- Julia Esser
- Division of Physiological Chemistry II, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
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41
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Rådmark O, Samuelsson B. Regulation of the activity of 5-lipoxygenase, a key enzyme in leukotriene biosynthesis. Biochem Biophys Res Commun 2010; 396:105-10. [PMID: 20494120 DOI: 10.1016/j.bbrc.2010.02.173] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Accepted: 02/28/2010] [Indexed: 01/22/2023]
Abstract
5-Lipoxygenase (5LO) catalyzes two steps in the biosynthesis of leukotrienes (LTs), lipid mediators of inflammation derived from arachidonic acid. LTs function in normal host defense, and have pathophysiological roles in chronic inflammatory diseases as asthma and atherosclerosis. Also, possible effects of 5LO products in relation to tumorigenesis have been described. Thus, insight regarding the biochemistry of 5LO is relevant for better understanding of normal physiology, and for development of therapy.
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Affiliation(s)
- Olof Rådmark
- Department of Medical Biochemistry and Biophysics, Division of Physiological Chemistry II, Karolinska Institutet, 17177 Stockholm, Sweden.
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Newcomer ME, Gilbert NC. Location, location, location: compartmentalization of early events in leukotriene biosynthesis. J Biol Chem 2010; 285:25109-14. [PMID: 20507998 DOI: 10.1074/jbc.r110.125880] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Leukotrienes (LTs), derived from arachidonic acid (AA) released from the membrane by the action of phospholipase A(2), are potent lipid mediators of the inflammatory response. In 1983, Dahlén et al. demonstrated that LTC(4), LTD(4), and LTE(4) mediate antigen-induced constriction of bronchi in tissue obtained from subjects with asthma (Dahlén, S. E., Hansson, G., Hedqvist, P., Björck, T., Granström, E., and Dahlén, B. (1983) Proc. Natl. Acad. Sci. U.S.A. 80, 1712-1716). Over the last 25+ years, substantial progress has been made in understanding how LTs exert their effects, and a broader appreciation for the numerous biological processes they mediate has emerged. LT biosynthesis is initiated by the action of 5-lipoxygenase (5-LOX), which catalyzes the transformation of AA to LTA(4) in a two-step reaction. Ca(2+) targets 5-LOX to the nuclear membrane, where it co-localizes with the 5-LOX-activating protein FLAP and, when present, the downstream enzyme LTC(4) synthase, both transmembrane proteins. Crystal structures of the AA-metabolizing LOXs, LTC(4) synthase, and FLAP combined with biochemical data provide a framework for understanding how subcellular organizations optimize the biosynthesis of these labile hydrophobic signaling compounds, which must navigate pathways that include both membrane and soluble enzymes. The insights these structures afford and the questions they engender are discussed in this minireview.
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Affiliation(s)
- Marcia E Newcomer
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana 70803, USA.
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Pharmacodynamics and pharmacokinetics of AM103, a novel inhibitor of 5-lipoxygenase-activating protein (FLAP). Clin Pharmacol Ther 2010; 87:437-44. [PMID: 20182424 DOI: 10.1038/clpt.2009.301] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The 5-lipoxygenase-activating protein (FLAP) gene and an increase in leukotriene (LT) production are linked to the risk of asthma, myocardial infarction, and stroke. We evaluated the pharmacodynamics, pharmacokinetics, and tolerability of 3-[3-tert-butylsulfanyl-1-[4-(6-methoxy-pyridin-3-yl)-benzyl]-5-(pyridin-2-ylmethoxy)-1H-indol-2-yl]-2,2-dimethyl-propionic acid (AM103), a novel FLAP inhibitor, in healthy subjects. Single and multiple doses of AM103 demonstrated dose-dependent inhibition of blood LTB(4) production and dose-related inhibition of urinary LTE(4). After a single oral dose (50-1,000 mg) of AM103, the maximum concentration (C(max)) and area under the curve (AUC) in plasma increased in a dose-dependent manner. After multiple-dose administration (50-1,000 mg once daily for 11 days), there were no significant differences in the pharmacokinetic parameters between the first and last days of treatment. AM103 was well tolerated at all doses in both the single- and multiple-dose cohorts. Further clinical trials with AM103 in inflammatory diseases are warranted.
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Bozza PT, D’Avila H, Almeida PE, Magalhães KG, Molinaro R, Almeida CJ, Maya-Monteiro CM. Lipid droplets in host–pathogen interactions. ACTA ACUST UNITED AC 2009. [DOI: 10.2217/clp.09.63] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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45
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Silva AR, Pacheco P, Vieira-de-Abreu A, Maya-Monteiro CM, D'Alegria B, Magalhães KG, de Assis EF, Bandeira-Melo C, Castro-Faria-Neto HC, Bozza PT. Lipid bodies in oxidized LDL-induced foam cells are leukotriene-synthesizing organelles: a MCP-1/CCL2 regulated phenomenon. Biochim Biophys Acta Mol Cell Biol Lipids 2009; 1791:1066-75. [DOI: 10.1016/j.bbalip.2009.06.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2008] [Revised: 06/09/2009] [Accepted: 06/23/2009] [Indexed: 12/01/2022]
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Kumar NS, Young RN. Design and synthesis of an all-in-one 3-(1,1-difluoroprop-2-ynyl)-3H-diazirin-3-yl functional group for photo-affinity labeling. Bioorg Med Chem 2009; 17:5388-95. [PMID: 19604700 DOI: 10.1016/j.bmc.2009.06.048] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2009] [Revised: 06/19/2009] [Accepted: 06/22/2009] [Indexed: 11/28/2022]
Abstract
A novel radioisotope-free photo-affinity probe containing the 3-(1,1-difluoroprop-2-ynyl)-3H-diazirin-3-yl functional group was designed and synthesized. This very compact functionality is envisaged to allow photochemically-induced coupling of a compound to its target followed by click reaction coupling with an azido-biotin reagent in order to facilitate purification of the labeled target. In a proof-of-concept study we have shown that 3-(1,1-difluoroprop-2-ynyl)-3H-diazirin-3-yl functional group could be photolyzed to efficiently furnish the methanol adduct 23 and that the generated highly unstable carbene does not react with the neighboring acetylene moiety. A subsequent click reaction with the azido-biotin derivative 25 proceeded smoothly to give triazole 26. This chemical probe should thus be of unique value for facilitating identification of the molecular structure of the target of a bioactive compound.
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Affiliation(s)
- Nag S Kumar
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6
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47
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Albertazzi L, Arosio D, Marchetti L, Ricci F, Beltram F. Quantitative FRET Analysis With the E0GFP-mCherry Fluorescent Protein Pair. Photochem Photobiol 2009; 85:287-97. [PMID: 18764891 DOI: 10.1111/j.1751-1097.2008.00435.x] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lorenzo Albertazzi
- Scuola Normale Superiore and Istituto Italiano di Tecnologia, Pisa, Italy.
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48
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Abstract
Leukotrienes (LTs) are signaling molecules derived from arachidonic acid that initiate and amplify innate and adaptive immunity. In turn, how their synthesis is organized on the nuclear envelope of myeloid cells in response to extracellular signals is not understood. We define the supramolecular architecture of LT synthesis by identifying the activation-dependent assembly of novel multiprotein complexes on the outer and inner nuclear membranes of mast cells. These complexes are centered on the integral membrane protein 5-Lipoxygenase-Activating Protein, which we identify as a scaffold protein for 5-Lipoxygenase, the initial enzyme of LT synthesis. We also identify these complexes in mouse neutrophils isolated from inflamed joints. Our studies reveal the macromolecular organization of LT synthesis.
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49
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Abstract
5-lipoxygenase (5-LO) catalyzes two steps in biosynthesis of leukotrienes (LTs), a group of lipid mediators of inflammation derived from arachidonic acid (AA). LT antagonists are used in treatment of asthma; more recently a potential role also in atherosclerosis has raised considerable interest. Furthermore, possible effects of 5-LO metabolites in relation to tumorigenesis have emerged. Thus, an understanding of the biochemistry of this lipoxygenase has potential implications for treatment of various diseases.
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Affiliation(s)
- Olof Rådmark
- Department Medical Biochemistry and Biophysics, Division of Physiological Chemistry II, Karolinska Institutet, S-17177 Stockholm, Sweden
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50
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Cornwell DG, Ma J. Nutritional benefit of olive oil: the biological effects of hydroxytyrosol and its arylating quinone adducts. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2008; 56:8774-8786. [PMID: 18783241 DOI: 10.1021/jf8015877] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Olive oil is the essential component of the Mediterranean diet, a nutritional regimen gaining ever-increasing renown for its beneficial effects on inflammation, cardiovascular disease, and cancer. A unique characteristic of olive oil is its enrichment in oleuropein, a member of the secoiridoid family, which hydrolyzes to the catechol hydroxytyrosol and functions as a hydrophilic phenolic antioxidant that is oxidized to its catechol quinone during redox cycling. Little effort has been spent on exploring the biological properties of the catechol hydroxytyrosol quinone, a strong arylating electrophile that forms Michael adducts with thiol nucleophiles in glutathione and proteins. This study compares the chemical and biological characteristics of hydroxytyrosol with those of the tocopherol family in which Michael adducts of arylating desmethyltocopherol quinones have been identified and correlated with biologic properties including cytotoxicity and induction of endoplasmic reticulum stress. It is noted that hydroxytyrosol and desmethyltocopherols share many similarities, suggesting that Michael adduct formation by an arylating quinone electrophile may contribute to the biological properties of both families, including the unique nutritional benefit of olive oil.
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Affiliation(s)
- David G Cornwell
- Department of Molecular and Cellular Biochemistry, College of Medicine, The Ohio State University, Columbus, Ohio 43210, USA.
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