1
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Tigyi GJ, Johnson LR, Lee SC, Norman DD, Szabo E, Balogh A, Thompson K, Boler A, McCool WS. Lysophosphatidic acid type 2 receptor agonists in targeted drug development offer broad therapeutic potential. J Lipid Res 2019; 60:464-474. [PMID: 30692142 PMCID: PMC6399510 DOI: 10.1194/jlr.s091744] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 01/15/2019] [Indexed: 11/20/2022] Open
Abstract
The growth factor-like lipid mediator, lysophosphatidic acid (LPA), is a potent signaling molecule that influences numerous physiologic and pathologic processes. Manipulation of LPA signaling is of growing pharmacotherapeutic interest, especially because LPA resembles compounds with drug-like features. The action of LPA is mediated through activation of multiple types of molecular targets, including six G protein-coupled receptors that are clear targets for drug development. However, the LPA signaling has been linked to pathological responses that include promotion of fibrosis, atherogenesis, tumorigenesis, and metastasis. Thus, a question arises: Can we harness, in an LPA-like drug, the many beneficial activities of this lipid without eliciting its dreadful actions? We developed octadecyl thiophosphate (OTP; subsequently licensed as Rx100), an LPA mimic with higher stability in vivo than LPA. This article highlights progress made toward developing analogs like OTP and exploring prosurvival and regenerative LPA signaling. We determined that LPA prevents cell death triggered by various cellular stresses, including genotoxic stressors, and rescues cells condemned to apoptosis. LPA2 agonists provide a new treatment option for secretory diarrhea and reduce gastric erosion caused by nonsteroidal anti-inflammatory drugs. The potential uses of LPA2 agonists like OTP and sulfamoyl benzoic acid-based radioprotectins must be further explored for therapeutic uses.
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Affiliation(s)
- Gabor J Tigyi
- Department of Physiology, University of Tennessee Health Science Center Memphis, Memphis, TN 38163
- RxBio Inc. Memphis, TN 38163
- Research Division Veterans Affairs Medical Center, Memphis, TN 38104
| | - Leonard R Johnson
- Department of Physiology, University of Tennessee Health Science Center Memphis, Memphis, TN 38163
- RxBio Inc. Memphis, TN 38163
| | - Sue Chin Lee
- Department of Physiology, University of Tennessee Health Science Center Memphis, Memphis, TN 38163
| | - Derek D Norman
- Department of Physiology, University of Tennessee Health Science Center Memphis, Memphis, TN 38163
- Research Division Veterans Affairs Medical Center, Memphis, TN 38104
| | - Erzsebet Szabo
- Department of Physiology, University of Tennessee Health Science Center Memphis, Memphis, TN 38163
| | - Andrea Balogh
- Department of Physiology, University of Tennessee Health Science Center Memphis, Memphis, TN 38163
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2
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Improved Synthesis of Dbibb as a New Anti-Radiation Agent. Chem Nat Compd 2018. [DOI: 10.1007/s10600-018-2388-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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3
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Reprint of: “Synthetic lipids and their role in defining macromolecular assemblies”. Chem Phys Lipids 2016; 194:149-57. [DOI: 10.1016/j.chemphyslip.2015.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 07/29/2015] [Accepted: 07/31/2015] [Indexed: 11/23/2022]
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4
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Molecular mechanisms of target recognition by lipid GPCRs: relevance for cancer. Oncogene 2015; 35:4021-35. [DOI: 10.1038/onc.2015.467] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 11/02/2015] [Accepted: 11/02/2015] [Indexed: 12/18/2022]
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5
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Parrill AL. Synthetic lipids and their role in defining macromolecular assemblies. Chem Phys Lipids 2015; 191:38-47. [DOI: 10.1016/j.chemphyslip.2015.07.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 07/29/2015] [Accepted: 07/31/2015] [Indexed: 10/23/2022]
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6
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Llona-Minguez S, Ghassemian A, Helleday T. Lysophosphatidic acid receptor (LPAR) modulators: The current pharmacological toolbox. Prog Lipid Res 2015; 58:51-75. [DOI: 10.1016/j.plipres.2015.01.004] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 01/15/2015] [Accepted: 01/20/2015] [Indexed: 12/17/2022]
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7
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Patil R, Szabó E, Fells JI, Balogh A, Lim KG, Fujiwara Y, Norman DD, Lee SC, Balazs L, Thomas F, Patil S, Emmons-Thompson K, Boler A, Strobos J, McCool SW, Yates CR, Stabenow J, Byrne GI, Miller DD, Tigyi GJ. Combined mitigation of the gastrointestinal and hematopoietic acute radiation syndromes by an LPA2 receptor-specific nonlipid agonist. ACTA ACUST UNITED AC 2015; 22:206-16. [PMID: 25619933 DOI: 10.1016/j.chembiol.2014.12.009] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2014] [Revised: 12/03/2014] [Accepted: 12/15/2014] [Indexed: 02/06/2023]
Abstract
Pharmacological mitigation of injuries caused by high-dose ionizing radiation is an unsolved medical problem. A specific nonlipid agonist of the type 2 G protein coupled receptor for lysophosphatidic acid (LPA2) 2-[4-(1,3-dioxo-1H,3H-benzoisoquinolin-2-yl)butylsulfamoyl]benzoic acid (DBIBB) when administered with a postirradiation delay of up to 72 hr reduced mortality of C57BL/6 mice but not LPA2 knockout mice. DBIBB mitigated the gastrointestinal radiation syndrome, increased intestinal crypt survival and enterocyte proliferation, and reduced apoptosis. DBIBB enhanced DNA repair by augmenting the resolution of γ-H2AX foci, increased clonogenic survival of irradiated IEC-6 cells, attenuated the radiation-induced death of human CD34(+) hematopoietic progenitors and enhanced the survival of the granulocyte/macrophage lineage. DBIBB also increased the survival of mice suffering from the hematopoietic acute radiation syndrome after total-body irradiation. DBIBB represents a drug candidate capable of mitigating acute radiation syndrome caused by high-dose γ-radiation to the hematopoietic and gastrointestinal system.
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Affiliation(s)
- Renukadevi Patil
- Department of Pharmaceutical Sciences, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Erzsébet Szabó
- Department of Physiology, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - James I Fells
- Department of Physiology, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Andrea Balogh
- Department of Physiology, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Keng G Lim
- Department of Physiology, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Yuko Fujiwara
- Department of Physiology, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Derek D Norman
- Department of Physiology, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Sue-Chin Lee
- Department of Physiology, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Louisa Balazs
- Department of Pathology, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Fridtjof Thomas
- Department of Preventive Medicine, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Shivaputra Patil
- Department of Pharmaceutical Sciences, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | | | | | | | | | | | - Jennifer Stabenow
- The Regional Biocontainment Laboratory, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Gerrald I Byrne
- The Regional Biocontainment Laboratory, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Duane D Miller
- Department of Pharmaceutical Sciences, The University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Gábor J Tigyi
- Department of Physiology, The University of Tennessee Health Science Center, Memphis, TN 38163, USA.
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8
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Patil R, Fells JI, Szabó E, Lim KG, Norman DD, Balogh A, Patil S, Strobos J, Miller DD, Tigyi GJ. Design and synthesis of sulfamoyl benzoic acid analogues with subnanomolar agonist activity specific to the LPA2 receptor. J Med Chem 2014; 57:7136-40. [PMID: 25100502 PMCID: PMC4148159 DOI: 10.1021/jm5007116] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Lysophosphatidic
acid (LPA) is a growth factor-like mediator and
a ligand for multiple GPCR. The LPA2 GPCR mediates antiapoptotic
and mucosal barrier-protective effects in the gut. We synthesized
sulfamoyl benzoic acid (SBA) analogues that are the first specific
agonists of LPA2, some with subnanomolar activity. We developed
an experimental SAR that is supported and rationalized by computational
docking analysis of the SBA compounds into the LPA2 ligand-binding
pocket.
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Affiliation(s)
- Renukadevi Patil
- Departments of Pharmaceutical Sciences and ‡Physiology, The University of Tennessee Health Science Center , Memphis, Tennessee 894 Union Avenue 38163 United States
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9
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Archbold JK, Martin JL, Sweet MJ. Towards selective lysophospholipid GPCR modulators. Trends Pharmacol Sci 2014; 35:219-26. [PMID: 24746475 DOI: 10.1016/j.tips.2014.03.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Revised: 03/13/2014] [Accepted: 03/14/2014] [Indexed: 01/08/2023]
Abstract
G-protein-coupled receptors (GPCRs) that recognize the lysophospholipids (LPLs) are grouped into two phylogenetically distinct families: the endothelial differentiation gene (Edg) and non-Edg GPCRs. Owing to their more recent identification, and hindered by a lack of selective pharmacological tools, our understanding of the functions and signaling pathways of the non-Edg GPCRs is still in its infancy. Targeting the non-conserved allosteric binding sites of the LPL GPCRs shows particular promise for the development of selective modulators by structure-based drug design. However, only one Edg GPCR (S1PR1) structure has been determined to date, and it has low sequence identity with the non-Edg GPCRs (<20%). Thus, a representative structure of a non-Edg GPCR remains a pressing objective for selective structure-based drug design. Obtaining selective modulators targeting the non-Edg receptors would help to unravel the biology behind these novel GPCRs and potentially will support therapeutic treatment of diseases such as cancer, inflammation, and neuropsychiatric disorders.
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Affiliation(s)
- Julia K Archbold
- Division of Chemistry and Structural Biology, The University of Queensland, Institute for Molecular Bioscience, St Lucia, Brisbane, QLD 4072, Australia.
| | - Jennifer L Martin
- Division of Chemistry and Structural Biology, The University of Queensland, Institute for Molecular Bioscience, St Lucia, Brisbane, QLD 4072, Australia
| | - Matthew J Sweet
- Division of Molecular and Cell Biology, The University of Queensland, Institute for Molecular Bioscience, St Lucia, Brisbane, QLD 4072, Australia
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10
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Abstract
The understanding of the role of the sphingosine 1-phosphate signaling system in immunology and host defense has deepened exponentially over the past 12 years since the discovery that lymphocyte egress was reversibly modulated by sphingosine 1-phosphate receptors, and with the development of fingolimod, a prodrug of a nonselective S1P receptor agonist, for therapeutic use in the treatment of relapsing, remitting multiple sclerosis. Innovative genetic and chemical approaches, together with structural biology, now provide a more detailed molecular understanding of a regulated lysophospholipid ligand with a variety of autocrine, paracrine, and systemic effects in physiology and pathology, based upon selective interactions with a high affinity and selective evolutionary cluster of G-protein-coupled receptors.
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11
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Development of lysophosphatidic acid pathway modulators as therapies for fibrosis. Future Med Chem 2013; 5:1935-52. [DOI: 10.4155/fmc.13.154] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Lysophosphatidic acid (LPA) is a class of bioactive phospholipid that displays a wide range of cellular effects via LPA receptors, of which six have been identified (LPAR1–6). In serum and plasma, LPA production occurs mainly by the hydrolysis of lysophosphatidylcholine by the phospholipase D activity of autotaxin (ATX). The involvement of the LPA pathway in driving chronic wound-healing conditions, such as idiopathic pulmonary fibrosis, has suggested targets in this pathway could provide potential therapeutic approaches. Mice with LPAR1 knockout or tissue-specific ATX deletion have demonstrated reduced lung fibrosis following bleomycin challenge. Therefore, strategies aimed at antagonizing LPA receptors or inhibiting ATX have gained considerable attention. This Review will summarize the current status of identifying small-molecule modulators of the LPA pathway. The therapeutic utility of LPA modulators for the treatment of fibrotic diseases will soon be revealed as clinical trials are already in progress in this area.
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12
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Rosen H, Stevens RC, Hanson M, Roberts E, Oldstone MBA. Sphingosine-1-phosphate and its receptors: structure, signaling, and influence. Annu Rev Biochem 2013; 82:637-62. [PMID: 23527695 DOI: 10.1146/annurev-biochem-062411-130916] [Citation(s) in RCA: 167] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The sphingosine-1-phosphate (S1P) receptor signaling system has biological and medical importance and is the first lipid G protein-coupled receptor (GPCR) structure to be solved to 2.8-Å resolution. S1P binds to five high-affinity GPCRs generating multiple downstream signals that play essential roles in vascular development and endothelial integrity, control of cardiac rhythm, and routine oral treatment of multiple sclerosis. Genetics, chemistry, and now structural biology have advanced this integrated biochemical system. The S1P receptors have a novel N-terminal fold that occludes access to the binding pocket from the extracellular environment as well as orthosteric and bitopic ligands with very different physicochemical properties. S1P receptors and metabolizing enzymes have been deleted, inducibly deleted, and knocked in as tagged or altered receptors in mice. An array of genetic models allows analysis of integrated receptor function in vivo. We can now directly understand causal relationships among protein expression, signal, and control points in physiology and pathology.
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Affiliation(s)
- Hugh Rosen
- Department of Chemical Physiology and Immunology, The Scripps Research Institute, La Jolla, California 92037, USA.
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13
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Structural Characterization of an LPA1 Second Extracellular Loop Mimetic with a Self-Assembling Coiled-Coil Folding Constraint. Int J Mol Sci 2013; 14:2788-807. [PMID: 23434648 PMCID: PMC3588015 DOI: 10.3390/ijms14022788] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 11/16/2012] [Accepted: 01/24/2013] [Indexed: 12/16/2022] Open
Abstract
G protein-coupled receptor (GPCR) structures are of interest as a means to understand biological signal transduction and as tools for therapeutic discovery. The growing number of GPCR crystal structures demonstrates that the extracellular loops (EL) connecting the membrane-spanning helices show tremendous structural variability relative to the more structurally-conserved seven transmembrane α-helical domains. The EL of the LPA(1) receptor have not yet been conclusively resolved, and bear limited sequence identity to known structures. This study involved development of a peptide to characterize the intrinsic structure of the LPA(1) GPCR second EL. The loop was embedded between two helices that assemble into a coiled-coil, which served as a receptor-mimetic folding constraint (LPA(1)-CC-EL2 peptide). The ensemble of structures from multi-dimensional NMR experiments demonstrated that a robust coiled-coil formed without noticeable deformation due to the EL2 sequence. In contrast, the EL2 sequence showed well-defined structure only near its C-terminal residues. The NMR ensemble was combined with a computational model of the LPA(1) receptor that had previously been validated. The resulting hybrid models were evaluated using docking. Nine different hybrid models interacted with LPA 18:1 as expected, based on prior mutagenesis studies, and one was additionally consistent with antagonist affinity trends.
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14
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Kiss GN, Fells JI, Gupte R, Lee SC, Liu J, Nusser N, Lim KG, Ray RM, Lin FT, Parrill AL, Sümegi B, Miller DD, Tigyi G. Virtual screening for LPA2-specific agonists identifies a nonlipid compound with antiapoptotic actions. Mol Pharmacol 2012; 82:1162-73. [PMID: 22968304 DOI: 10.1124/mol.112.079699] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Lysophosphatidic acid (LPA) is a highly potent endogenous lipid mediator that protects and rescues cells from programmed cell death. Earlier work identified the LPA₂ G protein-coupled receptor subtype as an important molecular target of LPA mediating antiapoptotic signaling. Here we describe the results of a virtual screen using single-reference similarity searching that yielded compounds 2-((9-oxo-9H-fluoren-2-yl)carbamoyl)benzoic acid (NSC12404), 2-((3-(1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl)propyl)thio)benzoic acid (GRI977143), 4,5-dichloro-2-((9-oxo-9H-fluoren-2-yl)carbamoyl)benzoic acid (H2L5547924), and 2-((9,10-dioxo-9,10-dihydroanthracen-2-yl)carbamoyl) benzoic acid (H2L5828102), novel nonlipid and drug-like compounds that are specific for the LPA₂ receptor subtype. We characterized the antiapoptotic action of one of these compounds, GRI977143, which was effective in reducing activation of caspases 3, 7, 8, and 9 and inhibited poly(ADP-ribose)polymerase 1 cleavage and DNA fragmentation in different extrinsic and intrinsic models of apoptosis in vitro. Furthermore, GRI977143 promoted carcinoma cell invasion of human umbilical vein endothelial cell monolayers and fibroblast proliferation. The antiapoptotic cellular signaling responses were present selectively in mouse embryonic fibroblast cells derived from LPA(1&2) double-knockout mice reconstituted with the LPA₂ receptor and were absent in vector-transduced control cells. GRI977143 was an effective stimulator of extracellular signal-regulated kinase 1/2 activation and promoted the assembly of a macromolecular signaling complex consisting of LPA₂, Na⁺ - H⁺ exchange regulatory factor 2, and thyroid receptor interacting protein 6, which has been shown previously to be a required step in LPA-induced antiapoptotic signaling. The present findings indicate that nonlipid LPA₂-specific agonists represent an excellent starting point for development of lead compounds with potential therapeutic utility for preventing the programmed cell death involved in many types of degenerative and inflammatory diseases.
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Affiliation(s)
- Gyöngyi N Kiss
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
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15
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Qian Y, Hamilton M, Sidduri A, Gabriel S, Ren Y, Peng R, Kondru R, Narayanan A, Truitt T, Hamid R, Chen Y, Zhang L, Fretland AJ, Sanchez RA, Chang KC, Lucas M, Schoenfeld RC, Laine D, Fuentes ME, Stevenson CS, Budd DC. Discovery of Highly Selective and Orally Active Lysophosphatidic Acid Receptor-1 Antagonists with Potent Activity on Human Lung Fibroblasts. J Med Chem 2012; 55:7920-39. [DOI: 10.1021/jm301022v] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Yimin Qian
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - Matthew Hamilton
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - Achyutharao Sidduri
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - Stephen Gabriel
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - Yonglin Ren
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - Ruoqi Peng
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - Rama Kondru
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - Arjun Narayanan
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - Terry Truitt
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - Rachid Hamid
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - Yun Chen
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - Lin Zhang
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - Adrian J. Fretland
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - Ruben Alvarez Sanchez
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - Kung-Ching Chang
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - Matthew Lucas
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - Ryan C. Schoenfeld
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - Dramane Laine
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - Maria E. Fuentes
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - Christopher S. Stevenson
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
| | - David C. Budd
- Discovery
Chemistry, ‡Discovery Inflammation and Respiratory Diseases, §Discovery Technology, ∥Pharmaceutical and
Analytical Research, and ⊥Drug Metabolism and Pharmacokinetics, Small Molecule Research, Pharmaceutical Research and Early Drug
Development, Hoffmann-La Roche, 340 Kingsland
Street, Nutley, New Jersey 07110, United States
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16
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Violet PC, Billon-Denis E, Robin P. Inhibition of lipid phosphate phosphatase activity by VPC32183 suppresses the ability of diacylglycerol pyrophosphate to activate ERK(1/2) MAP kinases. Biochim Biophys Acta Mol Cell Biol Lipids 2012; 1821:1394-405. [PMID: 22820196 DOI: 10.1016/j.bbalip.2012.07.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Revised: 06/26/2012] [Accepted: 07/11/2012] [Indexed: 11/17/2022]
Abstract
The lipidic metabolite, diacylglycerol pyrophosphate (DGPP), in its dioctanoyl form (DGPP 8:0), has been described as an antagonist for mammalian lysophosphatidic acid (LPA) receptors LPA1 and LPA3. In this study we show that DGPP 8:0 does not antagonize LPA dependent activation of ERK(1/2) MAP kinases but strongly stimulated them in various mammalian cell lines. LPA and DGPP 8:0 stimulation of ERK(1/2) occurred through different pathways. The DGPP 8:0 effect appeared to be dependent on PKC, Raf and MEK but was insensitive to pertussis toxin and did not involve G protein activation. Finally we showed that DGPP 8:0 effect on ERK(1/2) was dependent on its dephosphorylation by a phosphatase activity sharing lipid phosphate phosphatase properties. The inhibition of this phosphatase activity by VPC32183, a previously characterized LPA receptor antagonist, blocked the DGPP 8:0 effect on ERK(1/2) activation. Moreover, down-regulation of lipid phosphate phosphatase 1 (LPP1) expression by RNA interference technique also reduced DGPP 8:0-induced ERK(1/2) activation. Consistently, over expression of LPP1 in HEK293 cells increases DGPP 8:0 hydrolysis and this increased activity was inhibited by VPC32183. In conclusion, DGPP 8:0 does not exert its effect by acting on a G protein coupled receptor, but through its dephosphorylation by LPP1, generating dioctanoyl phosphatidic acid which in turn activates PKC. These results suggest that LPP1 could have a positive regulatory function on cellular signaling processes such as ERK(1/2) activation.
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Affiliation(s)
- Pierre-Christian Violet
- Université Paris-Sud 11, Institut de Biochimie et de Biophysique Moléculaire et Cellulaire, CNRS UMR 8619, 91405 Orsay CEDEX, France
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17
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Kozian DH, Evers A, Florian P, Wonerow P, Joho S, Nazare M. Selective non-lipid modulator of LPA5 activity in human platelets. Bioorg Med Chem Lett 2012; 22:5239-43. [PMID: 22801643 DOI: 10.1016/j.bmcl.2012.06.057] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Revised: 06/15/2012] [Accepted: 06/18/2012] [Indexed: 02/04/2023]
Abstract
Lysophosphatidic acid (LPA) is a potent activator of human platelets in vitro. Recently, the G protein-coupled receptor LPA5/GPR92 has been identified to be the relevant LPA receptor responsible for the activation of human platelets by LPA. In a high-throughput screening campaign we identified a diphenyl pyrazole carboxylic acid as a small-molecule inhibitor for LPA5. Confirmation for the specificity of this small molecule was achieved in human platelets as the relevant cellular in vitro model. We could confirm using antagonists for alternative LPA receptors that we identified in our work the first non-lipid, small-molecule inhibitor for LPA5/GPR92 specifically inhibiting LPA-mediated platelet activation in vitro.
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Affiliation(s)
- Detlef H Kozian
- Sanofi-Aventis Deutschland GmbH, Industriepark Hoechst, 65962 Frankfurt, Germany.
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18
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Abstract
Comparative modeling is a powerful technique to generate models of proteins from families already represented by members with experimentally characterized three-dimensional structures. The method is particularly important for modeling membrane-bound receptors in the G Protein-Coupled Receptor (GPCR) family, such as many of the lipid receptors (such as the cannabinoid, prostanoid, lysophosphatidic acid, sphingosine 1-phosphate, and eicosanoid receptor family members), as these represent particularly challenging targets for experimental structural characterization methods. Although challenging modeling targets, these receptors have been linked to therapeutic indications that vary from nociception to cancer, and thus are of interest as therapeutic targets. Accurate models of lipid receptors are therefore valuable tools in the drug discovery and optimization phases of therapeutic development. This chapter describes the construction and evaluation of comparative structural models of lipid receptors beginning with the selection of template structures.
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Affiliation(s)
- Abby L Parrill
- Department of Chemistry, The University of Memphis, Memphis, TN, USA.
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19
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Tsujiuchi T, Okabe K, Fukushima N. Genetic and epigenetic alterations of lysophosphatidic Acid receptor genes in rodent tumors by experimental models. J Toxicol Pathol 2011; 24:143-8. [PMID: 22272054 PMCID: PMC3234590 DOI: 10.1293/tox.24.143] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Accepted: 06/06/2011] [Indexed: 12/31/2022] Open
Abstract
Lysophosphatidic acid (LPA) is a bioactive mediator and induces several biological effects, including cell proliferation, migration, morphogenesis and differentiation. LPA interacts with at least six G protein-coupled receptors (GPCRs), including LPA receptor-1 (LPA(1)), LPA(2), LPA(3), LPA(4), LPA(5) and LPA(6). These receptors show different biological functions through the binding of LPA, depending on the type of cells. In human malignancies, a high level of LPA production was found in plasma and ascites in ovarian cancer cases. Moreover, aberrant expression levels of LPA receptor genes were detected in some cancer cells. Therefore, it is suggested that LPA receptors may be involved in the pathogenesis of tumor cells as well as LPA per se. Recently, we have reported that alterations of LPA receptor genes also occur in rodent tumors. In this review, we summarize the recent evidence in the investigations of LPA receptor alterations in rodent tumors by experimental models.
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Affiliation(s)
- Toshifumi Tsujiuchi
- Division of Cancer Biology and Bioinformatics,
Department of Life Science, Faculty of Science and Engineering, Kinki
University, 3-4-1 Kowakae, Higashiosaka, Osaka 577-8502, Japan
| | - Kyoko Okabe
- Division of Cancer Biology and Bioinformatics,
Department of Life Science, Faculty of Science and Engineering, Kinki
University, 3-4-1 Kowakae, Higashiosaka, Osaka 577-8502, Japan
| | - Nobuyuki Fukushima
- Division of Molecular Neurobiology, Department of
Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1
Kowakae, Higashiosaka, Osaka 577-8502, Japan
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20
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Abstract
G protein-coupled receptors (GPCRs) comprise a large class of transmembrane proteins that play critical roles in both normal physiology and pathophysiology. These critical roles offer targets for therapeutic intervention, as exemplified by the substantial fraction of current pharmaceutical agents that target members of this family. Tremendous contributions to our understanding of GPCR structure and dynamics have come from both indirect and direct structural characterization techniques. Key features of GPCR conformations derived from both types of characterization techniques are reviewed.
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Affiliation(s)
- Abby L. Parrill
- Department of Chemistry, The University of Memphis, Memphis, TN 38152, USA
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +1-901-678-2638; Fax: +1-901-678-3447
| | - Debra L. Bautista
- Christian Brothers High School, 5900 Walnut Grove Road, Memphis, TN 38120, USA; E-Mail: (D.L.B.)
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21
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Matsuzaki S, Ishizuka T, Hisada T, Aoki H, Komachi M, Ichimonji I, Utsugi M, Ono A, Koga Y, Dobashi K, Kurose H, Tomura H, Mori M, Okajima F. Lysophosphatidic acid inhibits CC chemokine ligand 5/RANTES production by blocking IRF-1-mediated gene transcription in human bronchial epithelial cells. THE JOURNAL OF IMMUNOLOGY 2010; 185:4863-72. [PMID: 20861350 DOI: 10.4049/jimmunol.1000904] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Lysophosphatidic acid (LPA) is a phospholipid mediator that exerts a variety of biological responses through specific G-protein-coupled receptors (LPA(1)-LPA(5) and P2Y5). LPA is thought to be involved in airway inflammation by regulating the expression of anti-inflammatory and proinflammatory genes. Chemokines such as CCL5/RANTES are secreted from airway epithelium and play a key role in allergic airway inflammation. CCL5/RANTES is a chemoattractant for eosinophils, T lymphocytes, and monocytes and seems to exacerbate asthma. We stimulated CCL5/RANTES production in a human bronchial epithelial cell line, BEAS-2B, with IFN-γ and TNF-α. When LPA was added, CCL5/RANTES mRNA expression and protein secretion were inhibited, despite the presence of IFN-γ and TNF-α. The LPA effect was attenuated by Ki16425, a LPA(1)/LPA(3) antagonist, but not by dioctylglycerol pyrophosphate 8:0, an LPA(3) antagonist. Pertussis toxin, the inhibitors for PI3K and Akt also attenuated the inhibitory effect of LPA on CCL5/RANTES secretion. We also identify the transcription factor IFN regulatory factor-1 (IRF-1) as being essential for CCL5/RANTES production. Interestingly, LPA inhibited IFN-γ and TNF-α-induced IRF-1 activation by blocking the binding of IRF-1 to its DNA consensus sequence without changing IRF-1 induction and its nuclear translocation. Ki16425, pertussis toxin, and PI3K inhibitors attenuated the inhibitory effect of LPA on IRF-1 activation. Our results suggest that LPA inhibits IFN-γ- and TNF-α-induced CCL5/RANTES production in BEAS-2B cells by blocking the binding of IRF-1 to the CCL5/RANTES promoter. LPA(1) coupled to G(i) and activation of PI3K is required for this unique effect.
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Affiliation(s)
- Shinichi Matsuzaki
- Department of Medicine and Molecular Science, Gunma University Graduate School of Medicine, Maebashi, Japan
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22
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Kumar SA, Hu X, Brown M, Kuschak B, Hernandez TA, Johnston JB, Gibson SB. Lysophosphatidic acid receptor expression in chronic lymphocytic leukemia leads to cell survival mediated though vascular endothelial growth factor expression. Leuk Lymphoma 2010; 50:2038-48. [PMID: 19860625 DOI: 10.3109/10428190903275586] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Lysophosphatidic acid (LPA) protects chronic lymphocytic leukemia (CLL) cells from apoptosis. Vascular endothelial growth factor (VEGF) also protects CLL cells against apoptosis. The mechanism for LPA protection against apoptosis in CLL cells is unknown. Herein, we show CLL cells express LPA receptors LPA(1-5) but in normal B cells, LPA(1) was rarely expressed and LPA(3,) LPA(4,) and LPA(6) were undetectable whereas the other LPA receptors were expressed. LPA plasma levels are similar in patients with CLL compared to healthy controls. In contrast, plasma levels of VEGF are elevated in patients with CLL compared to healthy controls and LPA treatment induced VEGF secretion in CLL cells. CLL cells also express VEGF receptors and LPA protection against Flu induced apoptosis is blocked by inhibition of VEGF receptor activation. These results indicate that LPA protects CLL cells from apoptosis through higher expression of LPA receptors and autocrine production of VEGF.
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23
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24
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Fells JI, Tsukahara R, Liu J, Tigyi G, Parrill AL. Structure-based drug design identifies novel LPA3 antagonists. Bioorg Med Chem 2009; 17:7457-64. [PMID: 19800804 DOI: 10.1016/j.bmc.2009.09.022] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2009] [Revised: 09/11/2009] [Accepted: 09/12/2009] [Indexed: 11/17/2022]
Abstract
Compound 5 ([5-(3-nitrophenoxy)-1,3-dioxo-1,3-dihydro-2-isoindol-2-yl]acetic acid) was identified as a weak selective LPA(3) antagonist (IC(50)=4504 nM) in a virtual screening effort to optimize a dual LPA(2 and 3) antagonist. Structure-based drug design techniques were used to prioritize similarity search matches of compound 5. This strategy rapidly identified 10 novel antagonists. The two most efficacious compounds identified inhibit activation of the LPA(3) receptor by 200 nM LPA with IC(50) values of 752 nM and 2992 nM. These compounds additionally define changes to our previously reported pharmacophore that will improve its ability to identify more potent and selective LPA(3) receptor antagonists. The results of the combined computational and experimental screening are reported.
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Affiliation(s)
- James I Fells
- Department of Chemistry and Computational Research on Materials Institute, The University of Memphis, Memphis, TN 38152, United States
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25
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Zhang H, Xu X, Gajewiak J, Tsukahara R, Fujiwara Y, Liu J, Fells JI, Perygin D, Parrill AL, Tigyi G, Prestwich GD. Dual activity lysophosphatidic acid receptor pan-antagonist/autotaxin inhibitor reduces breast cancer cell migration in vitro and causes tumor regression in vivo. Cancer Res 2009; 69:5441-9. [PMID: 19509223 DOI: 10.1158/0008-5472.can-09-0302] [Citation(s) in RCA: 137] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Signal transduction modifiers that modulate the lysophosphatidic acid (LPA) pathway have potential as anticancer agents. Herein, we describe metabolically stabilized LPA analogues that reduce cell migration and invasion and cause regression of orthotopic breast tumors in vivo. Two diastereoisomeric alpha-bromophosphonates (BrP-LPA) were synthesized, and the pharmacology was determined for five LPA G protein-coupled receptors (GPCRs). The syn and anti diastereomers of BrP-LPA are pan-LPA GPCR antagonists and are also nanomolar inhibitors of the lysophospholipase D activity of autotaxin, the dominant biosynthetic source of LPA. Computational models correctly predicted the diastereoselectivity of antagonism for three GPCR isoforms. The anti isomer of BrP-LPA was more effective than syn isomer in reducing migration of MDA-MB-231 cells, and the anti isomer was superior in reducing invasion of these cells. Finally, orthotopic breast cancer xenografts were established in nude mice by injection of MB-231 cells in an in situ cross-linkable extracellular matrix. After 2 weeks, mice were treated with the BrP-LPA alone (10 mg/kg), Taxol alone (10 mg/kg), or Taxol followed by BrP-LPA. All treatments significantly reduced tumor burden, and BrP-LPA was superior to Taxol in reducing blood vessel density in tumors. Moreover, both the anti- and syn-BrP-LPA significantly reduced tumors at 3 mg/kg.
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Affiliation(s)
- Honglu Zhang
- Department of Medicinal Chemistry, University of Utah, Salt Lake City, Utah 84108, USA
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26
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Williams JR, Khandoga AL, Goyal P, Fells JI, Perygin DH, Siess W, Parrill AL, Tigyi G, Fujiwara Y. Unique ligand selectivity of the GPR92/LPA5 lysophosphatidate receptor indicates role in human platelet activation. J Biol Chem 2009; 284:17304-17319. [PMID: 19366702 PMCID: PMC2719366 DOI: 10.1074/jbc.m109.003194] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Lysophosphatidic acid (LPA) is a ligand for LPA(1-3) of the endothelial differentiation gene family G-protein-coupled receptors, and LPA(4-8) is related to the purinergic family G-protein-coupled receptor. Because the structure-activity relationship (SAR) of GPR92/LPA(5) is limited and whether LPA is its preferred endogenous ligand has been questioned in the literature, in this study we applied a combination of computational and experimental site-directed mutagenesis of LPA(5) residues predicted to interact with the headgroup of LPA. Four residues involved in ligand recognition in LPA(5) were identified as follows: R2.60N mutant abolished receptor activation, whereas H4.64E, R6.62A, and R7.32A greatly reduced receptor activation. We also investigated the SAR of LPA(5) using LPA analogs and other non-lysophospholipid ligands. SAR revealed that the rank order of agonists is alkyl glycerol phosphate > LPA > farnesyl phosphates >> N-arachidonoylglycine. These results confirm LPA(5) to be a bona fide lysophospholipid receptor. We also evaluated several compounds with previously established selectivity for the endothelial differentiation gene receptors and found several that are LPA(5) agonists. A pharmacophore model of LPA(5) binding requirements was developed for in silico screening, which identified two non-lipid LPA(5) antagonists. Because LPA(5) transcripts are abundant in human platelets, we tested its antagonists on platelet activation and found that these non-lipid LPA(5) antagonists inhibit platelet activation. The present results suggest that selective inhibition of LPA(5) may provide a basis for future anti-thrombotic therapies.
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Affiliation(s)
- Jesica R Williams
- From the Department of Chemistry and Computational Research on Materials Institute, University of Memphis, Memphis, Tennessee 38152
| | - Anna L Khandoga
- Institute for Prevention of Cardiovascular Diseases, Medical Faculty, University of Munich, 80336 Munich, Germany
| | - Pankaj Goyal
- Institute for Prevention of Cardiovascular Diseases, Medical Faculty, University of Munich, 80336 Munich, Germany
| | - James I Fells
- From the Department of Chemistry and Computational Research on Materials Institute, University of Memphis, Memphis, Tennessee 38152
| | - Donna H Perygin
- From the Department of Chemistry and Computational Research on Materials Institute, University of Memphis, Memphis, Tennessee 38152
| | - Wolfgang Siess
- Institute for Prevention of Cardiovascular Diseases, Medical Faculty, University of Munich, 80336 Munich, Germany
| | - Abby L Parrill
- From the Department of Chemistry and Computational Research on Materials Institute, University of Memphis, Memphis, Tennessee 38152
| | - Gabor Tigyi
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163
| | - Yuko Fujiwara
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163.
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27
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Kooijman EE, Burger KNJ. Biophysics and function of phosphatidic acid: a molecular perspective. Biochim Biophys Acta Mol Cell Biol Lipids 2009; 1791:881-8. [PMID: 19362164 DOI: 10.1016/j.bbalip.2009.04.001] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2009] [Revised: 03/29/2009] [Accepted: 04/01/2009] [Indexed: 01/27/2023]
Abstract
Phosphatidic acid is the simplest (diacyl)glycerophospholipid present in cells and is now a well established second messenger with direct biological functions. It is specifically recognized by diverse proteins and plays an important role in cellular signaling and membrane dynamics in all eukaryotes. An important determinant of the biological functions of phosphatidic acid is its anionic headgroup. In this review we will focus on the peculiar ionization properties of phosphatidic acid and their crucial role in lipid-protein interactions. We will take a molecular approach focusing entirely on the physical chemistry of the lipid and develop a model explaining the ionization properties of phosphatidic acid, termed the electrostatic-hydrogen bond switch model. Diverse examples from recent literature in support of this model will be presented and the broader implications of our findings will be discussed.
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28
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Yamada T, Obo Y, Furukawa M, Hotta M, Yamasaki A, Honoki K, Fukushima N, Tsujiuchi T. Mutations of lysophosphatidic acid receptor-1 gene during progression of lung tumors in rats. Biochem Biophys Res Commun 2008; 378:424-7. [PMID: 19026987 DOI: 10.1016/j.bbrc.2008.11.044] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2008] [Accepted: 11/11/2008] [Indexed: 02/07/2023]
Abstract
Lysophosphatidic acid (LPA) is a bioactive phospholipid that stimulates cell proliferation, migration, and protects cells from apoptosis. It interacts with specific G protein-coupled transmembrane receptors. In this study, mutations of lysophosphatidic acid receptor-1 (LPA1) gene were investigated to clarify the possible molecular mechanisms underlying the development of lung tumors induced by N-nitrosobis(2-hydroxypropyl)amine (BHP) in rats. Male Wistar rats, 6 weeks of age, were given 2000ppm BHP in their drinking water for 12 weeks and then maintained without further treatment until sacrifice at 25 weeks. Genomic DNAs were extracted from paraffin-embedded tissues and exons 2-4 were examined for mutations, using polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) analysis. No LPA1 mutations were detected in 15 hyperplasias, but 2 out of 12 adenomas (16.7%) and 7 out of 17 adenocarcinomas (41.2%). These results suggest that mutations of LPA1 gene may be involved in the acquisition of growth advantage from adenomas to adenocarcinomas in lung carcinogenesis induced in rats by BHP.
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Affiliation(s)
- Takanori Yamada
- Laboratory of Cancer Biology and Bioinformatics, Department of Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502, Japan
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29
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Murph M, Nguyen G, Radhakrishna H, Mills GB. Sharpening the edges of understanding the structure/function of the LPA1 receptor: expression in cancer and mechanisms of regulation. BIOCHIMICA ET BIOPHYSICA ACTA 2008; 1781:547-57. [PMID: 18501205 PMCID: PMC2565514 DOI: 10.1016/j.bbalip.2008.04.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2008] [Revised: 04/11/2008] [Accepted: 04/19/2008] [Indexed: 02/03/2023]
Abstract
Since the molecular cloning of the vzg-1/Edg-2/LPA1 gene, studies have attempted to characterize LPA1 receptor functionality into a single categorical role, different from the other Edg-family LPA receptors. The desire to categorize LPA1 function has highlighted its complexity and demonstrated that the LPA1 receptor does not have one absolute function throughout every system. The central nervous system is highly enriched in the LPA1 receptor, suggesting an integral role in neuronal processes. Metastatic and invasive breast cancer also appears to have LPA-mediated LPA1 receptor functions that enhance phenotypes associated with tumorigenesis. LPA1 possesses a number of motifs conserved among G protein-coupled receptors (GPCRs): a DRY-like motif, a PDZ domain, Ser/Thr predicted sites of phosphorylation, a di-leucine motif, double cysteines in the tail and conserved residues that stabilize structure and determine ligand binding. The third intracellular loop of the LPA1 receptor may be the crux of receptor signaling and attenuation with phosphorylation of Thr-236 potentially a key determinant of basal LPA1 signaling. Mutagenesis data supports the notion that Thr-236 regulates this process since mutating Thr-236 to Ala-236 increased basal and LPA-mediated serum response factor (SRF) signaling activity and Lys-236 further increased this basal signaling. Here we describe progress on defining the major functions of the LPA1 receptor, discuss a context dependent dualistic role as both a negative regulator in cancer and a proto-oncogene, outline its structural components at the molecular amino acid level and present mutagenesis data on the third intracellular loop of the receptor.
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Affiliation(s)
- Mandi Murph
- Department of Systems Biology, MD Anderson Cancer Center, Houston, Texas 77030
| | - Giang Nguyen
- School of Biology and Petit Institute for Biosciences and Bioengineering, Georgia Institute of Technology, 315 Ferst Drive, Atlanta, Georgia 30332
| | - Harish Radhakrishna
- School of Biology and Petit Institute for Biosciences and Bioengineering, Georgia Institute of Technology, 315 Ferst Drive, Atlanta, Georgia 30332,The Coca-Cola Company, One Coca-Cola Plaza, TEC-437, Atlanta, GA 30301
| | - Gordon B. Mills
- Department of Systems Biology, MD Anderson Cancer Center, Houston, Texas 77030
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30
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Fujita R, Ma Y, Ueda H. Lysophosphatidic acid-induced membrane ruffling and brain-derived neurotrophic factor gene expression are mediated by ATP release in primary microglia. J Neurochem 2008; 107:152-60. [PMID: 18680554 DOI: 10.1111/j.1471-4159.2008.05599.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
We examined the effects of lysophosphatidic acid (LPA) on microglia, which may play an important role in the development and maintenance of neuropathic pain. LPA caused membrane ruffling as detected by scanning electron microscopy, and increased the expression of brain-derived neurotrophic factor (BDNF) in a primary culture of rat microglia, which express LPA(3), but not LPA(1) or LPA(2) receptors. These actions were inhibited by a Galpha(q/11)-antisense oligodeoxynucleotide (AS-ODN), U73122, an inhibitor of phospholipase C (PLC), and apyrase, which specifically degrades ATP and ADP. When ATP release was measured using a luciferin-luciferase bioluminescence assay, LPA was shown to increase it in an LPA(3) and PLC inhibitor-reversible manner. However, LPA-induced ATP release was also blocked by the Galpha(q/11) AS-ODN, but not by pertussis toxin. These results suggest that LPA induces the release of ATP from rat primary cultured microglia via the LPA(3) receptor, Galpha(q/11) and PLC, and that the released ATP or ectopically converted ADP may in turn cause membrane ruffling via P2Y(12) receptors and Galpha(i/o) activation, and BDNF expression via activation of P2X(4) receptors.
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Affiliation(s)
- Ryousuke Fujita
- Division of Molecular Pharmacology and Neuroscience, Nagasaki University Graduate School of Biomedical Sciences, Bunkyo-machi, Nagasaki, Japan
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31
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Lichte K, Rossi R, Danneberg K, Braak MT, Kürschner U, Jakobs KH, Kleuser B, Heringdorf DMZ. Lysophospholipid Receptor-Mediated Calcium Signaling in Human Keratinocytes. J Invest Dermatol 2008; 128:1487-98. [DOI: 10.1038/sj.jid.5701207] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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32
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Parrill AL. Lysophospholipid interactions with protein targets. Biochim Biophys Acta Mol Cell Biol Lipids 2008; 1781:540-6. [PMID: 18501204 DOI: 10.1016/j.bbalip.2008.04.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2008] [Revised: 04/22/2008] [Accepted: 04/23/2008] [Indexed: 12/21/2022]
Abstract
Bioactive lysophospholipids include lysophosphatidic acid (LPA), sphingosine 1-phosphate (S1P), cyclic-phosphatidic acid (CPA) and alkyl glycerolphosphate (AGP). These lipid mediators stimulate a variety of responses that include cell survival, proliferation, migration, invasion, wound healing, and angiogenesis. Responses to lysophospholipids depend upon interactions with biomolecular targets in the G protein-coupled receptor (GPCR) and nuclear receptor families, as well as enzymes. Our current understanding of lysophospholipid interactions with these targets is based on a combination of lysophospholipid analog structure activity relationship studies as well as more direct structural characterization techniques such as X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, and experimentally-validated molecular modeling. The direct structural characterization studies are the focus of this review, and provide the insight necessary to stimulate structure-based therapeutic lead discovery efforts in the future.
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Affiliation(s)
- Abby L Parrill
- Department of Chemistry, The University of Memphis, Memphis, TN 38152, USA.
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33
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Fells JI, Tsukahara R, Fujiwara Y, Liu J, Perygin DH, Osborne DA, Tigyi G, Parrill AL. Identification of non-lipid LPA3 antagonists by virtual screening. Bioorg Med Chem 2008; 16:6207-17. [PMID: 18467108 DOI: 10.1016/j.bmc.2008.04.035] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2008] [Revised: 04/15/2008] [Accepted: 04/16/2008] [Indexed: 10/22/2022]
Abstract
In the present study, we utilized virtual screening to identify LPA(3) antagonists. We have developed a three-point structure-based pharmacophore model based on known LPA(3) antagonists. This model was used to mine the NCI database. Docking, pharmacophore development, and database mining produced new, non-lipid leads. Experimental testing of seven computationally selected pharmacophore hits produced one potentiator and three antagonists, one of which displays both LPA(3) selectivity and nanomolar potency. Similarity searching in the ChemBridge database using the most promising lead as the search target produced four additional LPA(3) antagonists and a potent dual LPA(1&2) antagonist.
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Affiliation(s)
- James I Fells
- Department of Chemistry and Computational Research on Materials Institute, The University of Memphis, Memphis, TN 38152, USA
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Valentine WJ, Fells JI, Perygin DH, Mujahid S, Yokoyama K, Fujiwara Y, Tsukahara R, Van Brocklyn JR, Parrill AL, Tigyi G. Subtype-specific residues involved in ligand activation of the endothelial differentiation gene family lysophosphatidic acid receptors. J Biol Chem 2008; 283:12175-87. [PMID: 18316373 DOI: 10.1074/jbc.m708847200] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Lysophosphatidic acid (LPA) is a ligand for three endothelial differentiation gene family G protein-coupled receptors, LPA(1-3). We performed computational modeling-guided mutagenesis of conserved residues in transmembrane domains 3, 4, 5, and 7 of LPA(1-3) predicted to interact with the glycerophosphate motif of LPA C18:1. The mutants were expressed in RH7777 cells, and the efficacy (E(max)) and potency (EC(50)) of LPA-elicited Ca(2+) transients were measured. Mutation to alanine of R3.28 universally decreased both the efficacy and potency in LPA(1-3) and eliminated strong ionic interactions in the modeled LPA complexes. The alanine mutation at Q3.29 decreased modeled interactions and activation in LPA(1) and LPA(2) more than in LPA(3). The mutation W4.64A had no effect on activation and modeled LPA interaction of LPA(1) and LPA(2) but reduced the activation and modeled interactions of LPA(3). The R5.38A mutant of LPA(2) and R5.38N mutant of LPA(3) showed diminished activation by LPA; however, in LPA(1) the D5.38A mutation did not, and mutation to arginine enhanced receptor activation. In LPA(2), K7.36A decreased the potency of LPA; in LPA(1) this same mutation increased the E(max). In LPA(3), R7.36A had almost no effect on receptor activation; however, the mutation K7.35A increased the EC(50) in response to LPA 10-fold. In LPA(1-3), the mutation Q3.29E caused a modest increase in EC(50) in response to LPA but caused the LPA receptors to become more responsive to sphingosine 1-phosphate (S1P). Surprisingly micromolar concentrations of S1P activated the wild type LPA(2) and LPA(3) receptors, indicating that S1P may function as a weak agonist of endothelial differentiation gene family LPA receptors.
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Affiliation(s)
- William J Valentine
- Department of Physiology, The University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
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35
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Pham TCT, Kriwacki RW, Parrill AL. Peptide design and structural characterization of a GPCR loop mimetic. Biopolymers 2007; 86:298-310. [PMID: 17443712 DOI: 10.1002/bip.20745] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
G protein-coupled receptors (GPCRs) control fundamental aspects of human physiology and behaviors. Knowledge of their structures, especially for the loop regions, is limited and has principally been obtained from homology models, mutagenesis data, low resolution structural studies, and high resolution studies of peptide models of receptor segments. We developed an alternate methodology for structurally characterizing GPCR loops, using the human S1P(4) first extracellular loop (E1) as a model system. This methodology uses computational peptide designs based on transmembrane domain (TM) model structures in combination with CD and NMR spectroscopy. The characterized peptides contain segments that mimic the self-assembling extracellular ends of TM 2 and TM 3 separated by E1, including residues R3.28(121) and E3.29(122) that are required for sphingosine 1-phosphate (S1P) binding and receptor activation in the S1P(4) receptor. The S1P(4) loop mimetic peptide interacted specifically with an S1P headgroup analog, O-phosphoethanolamine (PEA), as evidenced by PEA-induced perturbation of disulfide cross-linked coiled-coil first extracellular loop mimetic (CCE1a) (1)H and (15)N backbone amide chemical shifts. CCE1a was capable of weakly binding PEA near biologically relevant residues R29 and E30, which correspond to R3.28 and E3.29 in the full-length S1P(4) receptor, confirming that it has adopted a biologically relevant conformation. We propose that the combination of coiled-coil TM replacement and conformational stabilization with an interhelical disulfide bond is a general design strategy that promotes native-like structure for loops derived from GPCRs.
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Affiliation(s)
- Truc-Chi T Pham
- Department of Chemistry and Computational Research on Materials Institute, The University of Memphis, Memphis, TN 38152, USA
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36
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Deng W, Shuyu E, Tsukahara R, Valentine WJ, Durgam G, Gududuru V, Balazs L, Manickam V, Arsura M, Vanmiddlesworth L, Johnson LR, Parrill AL, Miller DD, Tigyi G. The lysophosphatidic acid type 2 receptor is required for protection against radiation-induced intestinal injury. Gastroenterology 2007; 132:1834-51. [PMID: 17484878 PMCID: PMC3446791 DOI: 10.1053/j.gastro.2007.03.038] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2006] [Accepted: 01/24/2007] [Indexed: 12/02/2022]
Abstract
BACKGROUND & AIMS We recently identified lysophosphatidic acid (LPA) as a potent antiapoptotic agent for the intestinal epithelium. The objective of the present study was to evaluate the effect of octadecenyl thiophosphate (OTP), a novel rationally designed, metabolically stabilized LPA mimic, on radiation-induced apoptosis of intestinal epithelial cells in vitro and in vivo. METHODS The receptors and signaling pathways activated by OTP were examined in IEC-6 and RH7777 cell lines and wild-type and LPA(1) and LPA(2) knockout mice exposed to different apoptotic stimuli. RESULTS OTP was more efficacious than LPA in reducing gamma irradiation-, camptothecin-, or tumor necrosis factor alpha/cycloheximide-induced apoptosis and caspase-3-8, and caspase-9 activity in the IEC-6 cell line. In RH7777 cells lacking LPA receptors, OTP selectively protected LPA(2) but not LPA(1) and LPA(3) transfectants. In C57BL/6 and LPA(1) knockout mice exposed to 15 Gy gamma irradiation, orally applied OTP reduced the number of apoptotic bodies and activated caspase-3-positive cells but was ineffective in LPA(2) knockout mice. OTP, with higher efficacy than LPA, enhanced intestinal crypt survival in C57BL/6 mice but was without any effect in LPA(2) knockout mice. Intraperitoneally administered OTP reduced death caused by lethal dose (LD)(100/30) radiation by 50%. CONCLUSIONS Our data indicate that OTP is a highly effective antiapoptotic agent that engages similar prosurvival pathways to LPA through the LPA(2) receptor subtype.
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MESH Headings
- Administration, Oral
- Animals
- Apoptosis/drug effects
- Apoptosis/physiology
- Apoptosis/radiation effects
- Cell Line
- Cells, Cultured
- Dose-Response Relationship, Drug
- Female
- GTP-Binding Proteins/physiology
- Gamma Rays/adverse effects
- Gene Expression Regulation
- Injections, Intraperitoneal
- Intestinal Mucosa/metabolism
- Intestinal Mucosa/pathology
- Intestinal Mucosa/radiation effects
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mitogen-Activated Protein Kinases/physiology
- Nerve Tissue Proteins/pharmacology
- Organophosphorus Compounds/administration & dosage
- Organophosphorus Compounds/pharmacology
- Phosphatidylinositol 3-Kinases/physiology
- Radiation Injuries, Experimental/metabolism
- Radiation Injuries, Experimental/pathology
- Radiation Injuries, Experimental/prevention & control
- Receptors, Lysophosphatidic Acid/genetics
- Receptors, Lysophosphatidic Acid/physiology
- Signal Transduction/physiology
- Tumor Necrosis Factor-alpha/pharmacology
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Affiliation(s)
- Wenlin Deng
- Department of Physiology, University of Tennessee Health Sciences Center, Memphis
- RxBio Inc, Memphis
| | - E Shuyu
- Department of Physiology, University of Tennessee Health Sciences Center, Memphis
| | - Ryoko Tsukahara
- Department of Physiology, University of Tennessee Health Sciences Center, Memphis
| | - William J. Valentine
- Department of Physiology, University of Tennessee Health Sciences Center, Memphis
| | - Gangadhar Durgam
- Department of Pharmaceutical Science, University of Tennessee Health Sciences Center, Memphis
| | - Veeresa Gududuru
- Department of Pharmaceutical Science, University of Tennessee Health Sciences Center, Memphis
- RxBio Inc, Memphis
| | - Louisa Balazs
- Department of Pathology, University of Tennessee Health Sciences Center, Memphis
| | - Venkatraman Manickam
- Department of Pharmacology, University of Tennessee Health Sciences Center, Memphis
| | - Marcello Arsura
- Department of Pharmacology, University of Tennessee Health Sciences Center, Memphis
| | | | - Leonard R. Johnson
- Department of Physiology, University of Tennessee Health Sciences Center, Memphis
| | - Abby L. Parrill
- Department of Chemistry and Computational Research on Materials Institute, University of Memphis, Memphis, Tennessee
| | - Duane D. Miller
- Department of Pharmaceutical Science, University of Tennessee Health Sciences Center, Memphis
| | - Gabor Tigyi
- Department of Physiology, University of Tennessee Health Sciences Center, Memphis
- Department of Chemistry and Computational Research on Materials Institute, University of Memphis, Memphis, Tennessee
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37
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Jiang G, Xu Y, Fujiwara Y, Tsukahara T, Tsukahara R, Gajewiak J, Tigyi G, Prestwich GD. Alpha-substituted phosphonate analogues of lysophosphatidic acid (LPA) selectively inhibit production and action of LPA. ChemMedChem 2007; 2:679-90. [PMID: 17443831 PMCID: PMC3505595 DOI: 10.1002/cmdc.200600280] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2006] [Indexed: 12/23/2022]
Abstract
Isoform-selective agonists and antagonists of the lysophosphatidic acid (LPA) G-protein-coupled receptors (GPCRs) have important potential applications in cell biology and therapy. LPA GPCRs regulate cancer cell proliferation, invasion, angiogenesis, and biochemical resistance to chemotherapy- and radiotherapy-induced apoptosis. LPA and its analogues are also feedback inhibitors of the enzyme lysophospholipase D (lysoPLD, also known as autotaxin), a central regulator of invasion and metastasis. For cancer therapy, the ideal therapeutic profile would be a metabolically stabilized pan-LPA receptor antagonist that also inhibits lysoPLD. Herein we describe the synthesis of a series of novel alpha-substituted methylene phosphonate analogues of LPA. Each of these analogues contains a hydrolysis-resistant phosphonate mimic of the labile monophosphate of natural LPA. The pharmacological properties of these phosphono-LPA analogues were characterized in terms of LPA receptor subtype-specific agonist and antagonist activity using Ca(2+) mobilization assays in RH7777 and CHO cells expressing the individual LPA GPCRs. In particular, the methylene phosphonate LPA analogue is a selective LPA(2) agonist, whereas the corresponding alpha-hydroxymethylene phosphonate is a selective LPA(3) agonist. Most importantly, the alpha-bromomethylene and alpha-chloromethylene phosphonates show pan-LPA receptor subtype antagonist activity. The alpha-bromomethylene phosphonates are the first reported antagonists for the LPA(4) GPCR. Each of the alpha-substituted methylene phosphonates inhibits lysoPLD, with the unsubstituted methylene phosphonate showing the most potent inhibition. Finally, unlike many LPA analogues, none of these compounds activate the intracellular LPA receptor PPARgamma.
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Affiliation(s)
- Guowei Jiang
- Department of Medicinal Chemistry, The University of Utah, 419 Wakara Way, Suite 205, Salt Lake City, UT 84108-1257 (USA), Fax: (+1) 801-585-9053
| | - Yong Xu
- Department of Medicinal Chemistry, The University of Utah, 419 Wakara Way, Suite 205, Salt Lake City, UT 84108-1257 (USA), Fax: (+1) 801-585-9053
| | - Yuko Fujiwara
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163 (USA)
| | - Tamotsu Tsukahara
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163 (USA)
| | - Ryoko Tsukahara
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163 (USA)
| | - Joanna Gajewiak
- Department of Medicinal Chemistry, The University of Utah, 419 Wakara Way, Suite 205, Salt Lake City, UT 84108-1257 (USA), Fax: (+1) 801-585-9053
| | - Gabor Tigyi
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163 (USA)
| | - Glenn D. Prestwich
- Department of Medicinal Chemistry, The University of Utah, 419 Wakara Way, Suite 205, Salt Lake City, UT 84108-1257 (USA), Fax: (+1) 801-585-9053
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38
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Naor MM, Walker MD, Van Brocklyn JR, Tigyi G, Parrill AL. Sphingosine 1-phosphate pKa and binding constants: intramolecular and intermolecular influences. J Mol Graph Model 2007; 26:519-28. [PMID: 17467317 PMCID: PMC2040500 DOI: 10.1016/j.jmgm.2007.03.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2006] [Revised: 03/10/2007] [Accepted: 03/12/2007] [Indexed: 11/25/2022]
Abstract
The dissociation constant for an ionizable ligand binding to a receptor is dependent on its charge and therefore on its environmentally-influenced pKa value. The pKa values of sphingosine 1-phosphate (S1P) were studied computationally in the context of the wild type S1P1 receptor and the following mutants: E3.29Q, E3.29A, and K5.38A. Calculated pKa values indicate that S1P binds to S1P1 and its site mutants with a total charge of -1, including a +1 charge on the ammonium group and a -2 charge on the phosphate group. The dissociation constant of S1P binding to these receptors was studied as well. The models of wild type and mutant proteins originated from an active receptor model that was developed previously. We used ab initio RHF/6-31+G(d) to optimize our models in aqueous solution, where the solvation energy derivatives are represented by conductor-like polarizable continuum model (C-PCM) and integral equation formalism polarizable continuum model (IEF-PCM). Calculation of the dissociation constant for each mutant was determined by reference to the experimental dissociation constant of the wild type receptor. The computed dissociation constants of the E3.29Q and E3.29A mutants are three to five orders of magnitude higher than those for the wild type receptor and K5.38A mutant, indicating vital contacts between the S1P phosphate group and the carboxylate group of E3.29. Computational dissociation constants for K5.38A, E3.29A, and E3.29Q mutants were compared with experimentally determined binding and activation data. No measurable binding of S1P to the E3.29A and E3.29Q mutants was observed, supporting the critical contacts observed computationally. These results validate the quantitative accuracy of the model.
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Affiliation(s)
- Mor M. Naor
- Department of Chemistry and Computational Research on Materials Institute, The University of Memphis, Memphis, Tennessee 38152
| | - Michelle D. Walker
- Department of Physiology and University of Tennessee Cancer Institute, University of Tennessee Health Science Center, Memphis, Tennessee 38163
| | - James R. Van Brocklyn
- Division of Neuropathology, Department of Pathology, The Ohio State University, Columbus, Ohio 43210
| | - Gabor Tigyi
- Department of Physiology and University of Tennessee Cancer Institute, University of Tennessee Health Science Center, Memphis, Tennessee 38163
| | - Abby L. Parrill
- Department of Chemistry and Computational Research on Materials Institute, The University of Memphis, Memphis, Tennessee 38152
- CORRESPONDING AUTHOR Department of Chemistry and Computational Research on Materials Institute, The University of Memphis, Memphis, Tennessee 38152, 901-678-2638, FAX 901-678-3447,
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39
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Rosen H, Sanna MG, Cahalan SM, Gonzalez-Cabrera PJ. Tipping the gatekeeper: S1P regulation of endothelial barrier function. Trends Immunol 2007; 28:102-7. [PMID: 17276731 DOI: 10.1016/j.it.2007.01.007] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2006] [Revised: 01/03/2007] [Accepted: 01/22/2007] [Indexed: 10/23/2022]
Abstract
The lysophospholipid sphingosine 1-phosphate (S1P) is a pleiotropic signaling lipid present constitutively in plasma, and secreted locally at elevated concentrations at sites of inflammation. S1P maintains essential variable homeostatic functions in addition to inducing pathophysiology through the activation of five specific high-affinity G-protein-coupled receptors. Therefore, S1P can function as an extracellular rheostat regulating tonic and acutely evoked functions. Although S1P receptors can regulate lymphoid development and lymphocyte trafficking, and different opinions exist on the roles of receptor agonism and functional antagonism in regulating lymphocyte recirculation, this personal perspective highlights the pivotal control points regulated by constitutive and induced S1P receptor tone at vascular endothelial and lymphatic endothelial barriers, through which S1P agonism impacts on both innate and adaptive immunity. We also emphasize how specific, proof-of-concept chemical tools complement genetic approaches by enabling reversible perturbation of the S1P-S1P(1) receptor axis and, thus, clarifying in vivo mechanisms in the absence of developmental compensations.
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Affiliation(s)
- Hugh Rosen
- Department of Immunology, The Scripps Research Institute, La Jolla, CA 92037, USA.
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40
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Kooijman EE, Tieleman DP, Testerink C, Munnik T, Rijkers DTS, Burger KNJ, de Kruijff B. An electrostatic/hydrogen bond switch as the basis for the specific interaction of phosphatidic acid with proteins. J Biol Chem 2007; 282:11356-64. [PMID: 17277311 DOI: 10.1074/jbc.m609737200] [Citation(s) in RCA: 179] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Phosphatidic acid (PA) is a minor but important phospholipid that, through specific interactions with proteins, plays a central role in several key cellular processes. The simple yet unique structure of PA, carrying just a phosphomonoester head group, suggests an important role for interactions with the positively charged essential residues in these proteins. We analyzed by solid-state magic angle spinning 31P NMR and molecular dynamics simulations the interaction of low concentrations of PA in model membranes with positively charged side chains of membrane-interacting peptides. Surprisingly, lysine and arginine residues increase the charge of PA, predominantly by forming hydrogen bonds with the phosphate of PA, thereby stabilizing the protein-lipid interaction. Our results demonstrate that this electrostatic/hydrogen bond switch turns the phosphate of PA into an effective and preferred docking site for lysine and arginine residues. In combination with the special packing properties of PA, PA may well be nature's preferred membrane lipid for interfacial insertion of positively charged membrane protein domains.
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Affiliation(s)
- Edgar E Kooijman
- Department Biochemistry of Membranes, Bijvoet Center, Institute of Biomembranes, Utrecht University, Utrecht 3584 CH, The Netherlands.
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41
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Pan S, Mi Y, Pally C, Beerli C, Chen A, Guerini D, Hinterding K, Nuesslein-Hildesheim B, Tuntland T, Lefebvre S, Liu Y, Gao W, Chu A, Brinkmann V, Bruns C, Streiff M, Cannet C, Cooke N, Gray N. A Monoselective Sphingosine-1-Phosphate Receptor-1 Agonist Prevents Allograft Rejection in a Stringent Rat Heart Transplantation Model. ACTA ACUST UNITED AC 2006; 13:1227-34. [PMID: 17114004 DOI: 10.1016/j.chembiol.2006.09.017] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2006] [Revised: 09/15/2006] [Accepted: 09/20/2006] [Indexed: 11/19/2022]
Abstract
FTY720 is an immunomodulator with demonstrated efficacy in a phase II trial of relapsing multiple sclerosis. FTY720-phosphate, the active metabolite generated upon phosphorylation in vivo, acts as a potent agonist on four of the five known sphingosine-1-phosphate (S1P(1)) receptors. AUY954, an aminocarboxylate analog of FTY720, is a low nanomolar, monoselective agonist of the S1P(1) receptor. Due to its selectivity and pharmacokinetic profile, AUY954 is an excellent pharmacological probe of S1P(1)-dependent phenomena. Oral administration of AUY954 induces a profound and reversible reduction of circulating lymphocytes and, in combination with RAD001 (Certican/Everolimus, an mTOR inhibitor), is capable of prolonging the survival of cardiac allografts in a stringent rat transplantation model. This demonstrates that a selective agonist of the S1P(1) receptor is sufficient to achieve efficacy in an animal model of transplantation.
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Affiliation(s)
- Shifeng Pan
- Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, California 92121, USA
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42
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Meyer zu Heringdorf D, Jakobs KH. Lysophospholipid receptors: signalling, pharmacology and regulation by lysophospholipid metabolism. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2006; 1768:923-40. [PMID: 17078925 DOI: 10.1016/j.bbamem.2006.09.026] [Citation(s) in RCA: 282] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2006] [Accepted: 09/28/2006] [Indexed: 12/17/2022]
Abstract
The lysophospholipids, sphingosine-1-phosphate (S1P), lysophosphatidic acid (LPA), sphingosylphosphorylcholine (SPC) and lysophosphatidylcholine (LPC), activate diverse groups of G-protein-coupled receptors that are widely expressed and regulate decisive cellular functions. Receptors of the endothelial differentiation gene family are activated by S1P (S1P(1-5)) or LPA (LPA(1-3)); two more distantly related receptors are activated by LPA (LPA(4/5)); the GPR(3/6/12) receptors have a high constitutive activity but are further activated by S1P and/or SPC; and receptors of the OGR1 cluster (OGR1, GPR4, G2A, TDAG8) appear to be activated by SPC, LPC, psychosine and/or protons. G-protein-coupled lysophospholipid receptors regulate cellular Ca(2+) homoeostasis and the cytoskeleton, proliferation and survival, migration and adhesion. They have been implicated in development, regulation of the cardiovascular, immune and nervous systems, inflammation, arteriosclerosis and cancer. The availability of S1P and LPA at their G-protein-coupled receptors is regulated by enzymes that generate or metabolize these lysophospholipids, and localization plays an important role in this process. Besides FTY720, which is phosphorylated by sphingosine kinase-2 and then acts on four of the five S1P receptors of the endothelial differentiation gene family, other compounds have been identified that interact with more ore less selectivity with lysophospholipid receptors.
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43
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Boucharaba A, Serre CM, Guglielmi J, Bordet JC, Clézardin P, Peyruchaud O. The type 1 lysophosphatidic acid receptor is a target for therapy in bone metastases. Proc Natl Acad Sci U S A 2006; 103:9643-8. [PMID: 16769891 PMCID: PMC1480460 DOI: 10.1073/pnas.0600979103] [Citation(s) in RCA: 171] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Platelet-derived lysophosphatidic acid (LPA) supports the progression of breast and ovarian cancer metastasis to bone. The mechanisms through which LPA promotes bone metastasis formation are, however, unknown. Here we report that silencing of the type 1 LPA receptor (LPA(1)) in cancer cells blocks the production of tumor-derived cytokines that are potent activators of osteoclast-mediated bone destruction and significantly reduces the progression of osteolytic bone metastases. Moreover, functional blockade of LPA action on its cognate receptor LPA(1) using a pharmacological antagonist mimics the effects of silencing LPA(1) in tumor cells in vitro and substantially reduces bone metastasis progression in animals. Overall, these results suggest that inhibition of platelet-derived LPA action on LPA(1) expressed by tumor cells may be a promising therapeutic target for patients with bone metastases.
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Affiliation(s)
- Ahmed Boucharaba
- *Institut National de la Santé et de la Recherche Médicale (INSERM), U664, 69372 Lyon, France
- Université Claude Bernard Lyon 1, 69008 Lyon, France; and
| | - Claire-Marie Serre
- *Institut National de la Santé et de la Recherche Médicale (INSERM), U664, 69372 Lyon, France
- Université Claude Bernard Lyon 1, 69008 Lyon, France; and
| | - Julien Guglielmi
- *Institut National de la Santé et de la Recherche Médicale (INSERM), U664, 69372 Lyon, France
- Université Claude Bernard Lyon 1, 69008 Lyon, France; and
| | - Jean-Claude Bordet
- Université Claude Bernard Lyon 1, 69008 Lyon, France; and
- Faculté de Médecine Laënnec, EA3735, Laboratoire d’Hémobiologie, 69008 Lyon, France
| | - Philippe Clézardin
- *Institut National de la Santé et de la Recherche Médicale (INSERM), U664, 69372 Lyon, France
- Université Claude Bernard Lyon 1, 69008 Lyon, France; and
| | - Olivier Peyruchaud
- *Institut National de la Santé et de la Recherche Médicale (INSERM), U664, 69372 Lyon, France
- Université Claude Bernard Lyon 1, 69008 Lyon, France; and
- To whom correspondence should be addressed. E-mail:
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Kotarsky K, Boketoft A, Bristulf J, Nilsson NE, Norberg A, Hansson S, Owman C, Sillard R, Leeb-Lundberg LMF, Olde B. Lysophosphatidic acid binds to and activates GPR92, a G protein-coupled receptor highly expressed in gastrointestinal lymphocytes. J Pharmacol Exp Ther 2006; 318:619-28. [PMID: 16651401 DOI: 10.1124/jpet.105.098848] [Citation(s) in RCA: 187] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Here, the ligand binding, activation, and tissue distribution of the orphan G protein-coupled receptor (GPCR) GPR92 were studied. GPR92 binds and is activated by compounds based on the lysophosphatidic acid (LPA) backbone. The binding of LPA to GPR92 was of high affinity (K(D) = 6.4 +/- 0.9 nM) and led to an increase in both phosphoinositide hydrolysis and cAMP production. GPR92 is atypical in that it has a low sequence homology with the classic LPA(1-3) receptors (21-22%). Expression of GPR92 is mainly found in heart, placenta, spleen, brain, lung, and gut. Notably, GPR92 is highly expressed in the lymphocyte compartment of the gastrointestinal tract. It is the most abundant GPCR activated by LPA found in the small intestinal intraepithelial CD8+ cytotoxic T cells.
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Affiliation(s)
- Knut Kotarsky
- Division of Immunology, Department for Experimental Medical Science, Lund University, Lund, Sweden
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45
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Abstract
We studied the lysophosphatidic acid receptor-1 (LPA1) gene, which we found to be expressed endogenously in cultured hippocampal neurons, and in vivo in young (1-week-old) rat brain slices. Overexpressed green fluorescent protein (GFP)-tagged, membrane-associated LPA1 accumulated in a punctate manner over the entire dendritic tree and caused an increase in dendritic spine density. About half of the dendritic spines in the LPA1-transfected neurons displayed distinct fluorescent puncta, and this subset of spines was also substantially larger than puncta-free, LPA1-transfected or control GFP spines. This phenotype could also be seen in cells transfected with a ligand-binding, defective mutant and is therefore not dependent on interaction with an ambient ligand. While spontaneous miniature excitatory synaptic currents were of the same amplitudes, they decayed slower in LPA1-transfected neurons compared with GFP controls. We propose that LPA1 may play a role in the formation and modulation of the dendritic spine synapse.
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Affiliation(s)
- Yair Pilpel
- Department of Neurobiology, The Weizmann Institute, Rehovot, Israel.
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46
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Abstract
Lysophosphatidic acid (LPA; 1-acyl-3-phosphoglycerol) exerts its biological activity through both extracellular and intracellular targets. Receptor targets include the cell-surface G-protein-coupled receptors LPA(1-4) and the nuclear PPAR-gamma (peroxisome-proliferator-activated receptor gamma). Enzyme targets include the secreted cancer cell motility factor, autotaxin, and the transmembrane phosphatases, LPP1-3 (where LPP stands for lipid phosphate phosphatase). Ion channel targets include the two pore domain ion channels in the TREK family, TREK-1, TREK-2 and TRAAK. Structural features of these targets and their interactions with LPA are reviewed.
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Durgam GG, Tsukahara R, Makarova N, Walker MD, Fujiwara Y, Pigg KR, Baker DL, Sardar VM, Parrill AL, Tigyi G, Miller DD. Synthesis and pharmacological evaluation of second-generation phosphatidic acid derivatives as lysophosphatidic acid receptor ligands. Bioorg Med Chem Lett 2005; 16:633-40. [PMID: 16263282 DOI: 10.1016/j.bmcl.2005.10.031] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2005] [Revised: 10/08/2005] [Accepted: 10/12/2005] [Indexed: 10/25/2022]
Abstract
Short-chain phosphatidic acid derivatives, dioctanoyl glycerol pyrophosphate (DGPP 8:0, 1) and phosphatidic acid 8:0 (PA 8:0, 2), were previously identified as subtype-selective LPA(1) and LPA(3) receptor antagonists. Recently, we reported that the replacement of the phosphate headgroup by thiophosphate in a series of fatty alcohol phosphates (FAP) improves agonist as well as antagonist activities at LPA GPCR. Here, we report the synthesis of stereoisomers of PA 8:0 analogs and their biological evaluation at LPA GPCR, PPARgamma, and ATX. The results indicate that LPA receptors stereoselectively interact with glycerol backbone modified ligands. We observed entirely stereospecific responses by dioctyl PA 8:0 compounds, in which (R)-isomers were found to be agonists and (S)-isomers were antagonists of LPA GPCR. From this series, we identified compound 13b as the most potent LPA(3) receptor subtype-selective agonist (EC(50)=3 nM), and 8b as a potent and selective LPA(3) receptor antagonist (K(i)=5 nM) and inhibitor of ATX (IC(50)=600 nM). Serinediamide phosphate 19b was identified as an LPA(3) receptor specific antagonist with no effect on LPA(1), LPA(2), and PPARgamma.
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Affiliation(s)
- Gangadhar G Durgam
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN 38163, USA
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Xu YJ, Saini HK, Cheema SK, Dhalla NS. Mechanisms of lysophosphatidic acid-induced increase in intracellular calcium in vascular smooth muscle cells. Cell Calcium 2005; 38:569-79. [PMID: 16216324 DOI: 10.1016/j.ceca.2005.08.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2005] [Revised: 08/30/2005] [Accepted: 08/30/2005] [Indexed: 11/17/2022]
Abstract
Although lysophosphatidic acid (LPA) is known to cause an increase in intracellular Ca2+ concentration ([Ca2+]i) in vascular smooth muscle cells (VSMCs), the mechanisms of [Ca2+]i mobilization by LPA are not fully understood. In the present study, the effect of LPA on [Ca2+]i mobilization in cultured A10 VSMCs was examined by Fura-2 fluorescence technique. The expression of LPA receptors was studied by immunostaining. LPA was observed to increase [Ca2+]i in a concentration-dependent manner; this increase was dependent on the concentration of extracellular Ca2+. Both sarcolemmal (SL) Na(+)-Ca2+ exchange inhibitors (amiloride, Ni2+ and KB-R7943) and Na(+)-H+ exchange inhibitor (MIA) as well as SL store-operated Ca2+ channel (SOC) antagonists (SK&F 96365, tyrphostin A9 and gadolinium), unlike SL Ca2+ channel antagonists (verapamil and diltiazem), inhibited the LPA-induced increase in [Ca2+]i. In addition, sarcoplasmic reticulum (SR) Ca2+ channel blocker (ryanodine), SR Ca2+ channel opener (caffeine), SR Ca2+ pump ATPase inhibitor (thapsigargin) and inositol 1,4,5-trisphosphate (InsP3) receptor antagonists (xestospongin and 2-aminoethoxydiphenyl borate) were found to inhibit the LPA-induced Ca2+ mobilization. Furthermore, phospholipase C (PLC) inhibitor (U 73122) and protein kinase C (PKC) activator (phorbol 12-myristate 13-acetate) attenuated the LPA-induced increase in [Ca2+]i. These results indicate that Ca2+ mobilization by LPA involves extracellular Ca2+ entry through SL Na(+)-Ca2+ exchanger, Na(+)-H+ exchanger and SL SOCs. In addition, ryanodine-sensitive and InsP(3)-sensitive intracellular Ca2+ pools may be associated with the LPA-induced increase in [Ca2+]i. Furthermore, the LPA-induced [Ca2+]i mobilization in VSMCs seems to be due to the activation of both PLC and PKC.
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Affiliation(s)
- Yan-Jun Xu
- Institute of Cardiovascular Sciences, St. Boniface General Hospital Research Centre, Department of Physiology, Faculty of Medicine, University of Manitoba, R3021-351 Tache Avenue, Winnipeg, Man., Canada
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Fujiwara Y, Sardar V, Tokumura A, Baker D, Murakami-Murofushi K, Parrill A, Tigyi G. Identification of Residues Responsible for Ligand Recognition and Regioisomeric Selectivity of Lysophosphatidic Acid Receptors Expressed in Mammalian Cells. J Biol Chem 2005; 280:35038-50. [PMID: 16115890 DOI: 10.1074/jbc.m504351200] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The endothelial differentiation gene family encodes three highly homologous G protein-coupled receptors for lysophosphatidic acid (LPA). Based on baculoviral overexpression studies, differences have been proposed in the structure-activity relationship (SAR) of these receptors. We have compared the SAR of the individual receptors either overexpressed transiently at high or at lower levels following stable transfection in LPA-nonresponsive RH7777 cells. The SAR in transfected RH7777 cells was markedly different from that described in insect cells. The LPA(3) receptor has been proposed to be selectively activated by unsaturated LPA species and shows a strong preference for sn-2 versus the sn-1 acyl-LPA regioisomer. Because of the short half-life of sn-2 LPA due to acyl migration under some conditions, we have synthesized acyl migration-resistant analogs using an acetyl group in place of the free hydroxyl group in order to evaluate LPA receptor SAR. Only LPA(1) and LPA(2) showed regioisomeric preference and only for the 18:2 fatty acyl-stabilized LPA sn-1 regioisomer. To identify residues involved in ligand recognition of LPA(3), we developed and validated computational models of LPA(3) complexes with the analogs studied. The models revealed that Arg-3.28 and Gln-3.29 conserved within the LPA-selective endothelial differentiation gene receptors and the more variable Lys-7.35 and Arg-5.38 of LPA(3) form critical interactions with the polar headgroup of LPA. The models identified Leu-2.60 and Val-7.39 of LPA(3) underlying the regioisomer-selective interaction with the acetyl group of the stabilized regioisomers. Mutation of Leu-2.60 to alanine selectively increased the EC(50) of the sn-2 acetyl-LPA regioisomers, whereas alanine replacement of Val-7.39 profoundly affected both regioisomers.
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Affiliation(s)
- Yuko Fujiwara
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38152, USA
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Fieger CB, Huang MC, Van Brocklyn JR, Goetzl EJ. Type 1 sphingosine 1-phosphate G protein-coupled receptor signaling of lymphocyte functions requires sulfation of its extracellular amino-terminal tyrosines. FASEB J 2005; 19:1926-8. [PMID: 16148028 PMCID: PMC1557661 DOI: 10.1096/fj.05-4476fje] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The type 1 sphingosine 1-phosphate (S1P) G protein-coupled receptor (S1P1) transduces signals from S1P that mediate thymocyte emigration, T cell transmigration of lymph nodes, and T cell chemotaxis in tissues. Alterations in expression of functional S1P1 receptors by lymphocytes are the major mechanisms controlling their responses to S1P and were thought to be solely a consequence of the balance between surface down-regulation and insertion. However, results now show that lack of sulfation of tyrosines 19 and 22 of the extracellular N terminus of S1P1 diminishes high-affinity S1P binding and decreases S1P signaling of T cell migration and other functions. Non-sulfatable mutant (Y19,22F)S1P1 endows T cells with lower-affinity binding of [32P]S1P than wild-type S1P1 and transduces lesser effects of S1P on chemotaxis, chemokine-elicited chemotaxis, and T cell receptor-mediated proliferation and cytokine generation. Inhibition of S1P1 tyrosine sulfation or sulfatase removal of S1P1 sulfate in mouse CD4 T cells suppresses immune functional effects of S1P. Tyrosine sulfation of S1P1 may be a major controller of S1P effects on T cell traffic.
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Affiliation(s)
| | - Mei-Chuan Huang
- Medicine and Microbiology-Immunology, University of California, San Francisco, California; and
| | | | - Edward J. Goetzl
- Medicine and Microbiology-Immunology, University of California, San Francisco, California; and
- Corresponding author: Edward J. Goetzl, University of California, Room UB8B, UC Box 0711, 533 Parnassus at 4th Ave., San Francisco, CA, 94143-0711. E-mail:
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