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Nagarajan S, Qian ZY, Marimuthu P, Alkayed NJ, Kaul S, Barnes AP. Mapping the Molecular Architecture Required for Lipid-Binding Pockets Using a Subset of Established and Orphan G-Protein Coupled Receptors. J Chem Inf Model 2021; 61:3442-3452. [PMID: 34242503 DOI: 10.1021/acs.jcim.1c00335] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
G-protein coupled receptors (GPCRs) sense a wide variety of stimuli, including lipids, and transduce signals to the intracellular environment to exert various physiological responses. However, the structural features of GPCRs responsible for detecting and triggering responses to distinct lipid ligands have only recently begun to be revealed. 14,15-epoxyeicosatrienoic acid (14,15-EET) is one such lipid mediator that plays an essential role in the vascular system, displaying both vasodilatory and anti-inflammatory properties. We recently reported multiple low-affinity 14,15-EET-binding GPCRs, but the mechanism by which these receptors sense 14,15-EET remains unclear. Here, we have taken a combined computational and experimental approach to identify and confirm critical residues and properties within the lipid-binding pocket. Furthermore, we generated mutants to engineer selected GPCR-predicted binding sites to either confer or abolish 14,15-EET-induced signaling. Our structure-function analyses indicate that hydrophobic and positively charged residues of the receptor-binding pocket are prerequisites for recognizing lipid ligands such as 14,15-EET and possibly other eicosanoids.
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Affiliation(s)
- Shanthi Nagarajan
- The Knight Cardiovascular Institute, Oregon Health Science University Portland, Portland, Oregon 97239, United States.,Medicinal Chemistry Core, Oregon Health Science University Portland, Portland, Oregon 97239, United States
| | - Zu Yuan Qian
- The Knight Cardiovascular Institute, Oregon Health Science University Portland, Portland, Oregon 97239, United States.,Department of Anesthesiology & Perioperative Medicine, Oregon Health Science University Portland, Portland, Oregon 97239, United States
| | - Parthiban Marimuthu
- Pharmaceutical Science Laboratory and Structural Bioinformatics Laboratory, Faculty of Science and Engineering, Åbo Akademi University, FI-20520 Turku, Finland
| | - Nabil J Alkayed
- The Knight Cardiovascular Institute, Oregon Health Science University Portland, Portland, Oregon 97239, United States.,Department of Anesthesiology & Perioperative Medicine, Oregon Health Science University Portland, Portland, Oregon 97239, United States
| | - Sanjiv Kaul
- The Knight Cardiovascular Institute, Oregon Health Science University Portland, Portland, Oregon 97239, United States
| | - Anthony P Barnes
- The Knight Cardiovascular Institute, Oregon Health Science University Portland, Portland, Oregon 97239, United States.,Department of Anesthesiology & Perioperative Medicine, Oregon Health Science University Portland, Portland, Oregon 97239, United States
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2
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The G-Protein-Coupled Estrogen Receptor (GPER) Regulates Trimethylation of Histone H3 at Lysine 4 and Represses Migration and Proliferation of Ovarian Cancer Cells In Vitro. Cells 2021; 10:cells10030619. [PMID: 33799631 PMCID: PMC8001910 DOI: 10.3390/cells10030619] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 03/08/2021] [Accepted: 03/09/2021] [Indexed: 02/06/2023] Open
Abstract
Histone H3 lysine 4 trimethylation (H3K4me3) is one of the most recognized epigenetic regulators of transcriptional activity representing, an epigenetic modification of Histone H3. Previous reports have suggested that the broad H3K4me3 domain can be considered as an epigenetic signature for tumor-suppressor genes in human cells. G-protein-coupled estrogen receptor (GPER), a new membrane-bound estrogen receptor, acts as an inhibitor on cell growth via epigenetic regulation in breast and ovarian cancer cells. This study was conducted to evaluate the relationship of GPER and H3K4me3 in ovarian cancer tissue samples as well as in two different cell lines (Caov3 and Caov4). Silencing of GPER by a specific siRNA and two selective regulators with agonistic (G1) and antagonistic (G15) activity were applied for consecutive in vitro studies to investigate their impacts on tumor cell growth and the changes in phosphorylated ERK1/2 (p-ERK1/2) and H3K4me3. We found a positive correlation between GPER and H3K4me3 expression in ovarian cancer patients. Patients overexpressing GPER as well as H3K4me3 had significantly improved overall survival. Increased H3K4me3 and p-ERK1/2 levels and attenuated cell proliferation and migration were observed in Caov3 and Caov4 cells via activation of GPER by G1. Conversely, antagonizing GPER activity by G15 resulted in opposite effects in the Caov4 cell line. In conclusion, interaction of GPER and H3K4me3 appears to be of prognostic significance for ovarian cancer patients. The results of the in vitro analyses confirm the biological rationale for their interplay and identify GPER agonists, such as G1, as a potential therapeutic approach for future investigations.
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3
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Melis C, Beauvais G, Muntean BS, Cirnaru MD, Otrimski G, Creus-Muncunill J, Martemyanov KA, Gonzalez-Alegre P, Ehrlich ME. Striatal Dopamine Induced ERK Phosphorylation Is Altered in Mouse Models of Monogenic Dystonia. Mov Disord 2021; 36:1147-1157. [PMID: 33458877 DOI: 10.1002/mds.28476] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 12/02/2020] [Accepted: 12/04/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Similar to some monogenic forms of dystonia, levodopa-induced dyskinesia is a hyperkinetic movement disorder with abnormal nigrostriatal dopaminergic neurotransmission. Molecularly, it is characterized by hyper-induction of phosphorylation of extracellular signal-related kinase in response to dopamine in medium spiny neurons of the direct pathway. OBJECTIVES The objective of this study was to determine if mouse models of monogenic dystonia exhibit molecular features of levodopa-induced dyskinesia. METHODS Western blotting and quantitative immunofluorescence was used to assay baseline and/or dopamine-induced levels of the phosphorylated kinase in the striatum in mouse models of DYT1, DYT6, and DYT25 expressing a reporter in dopamine D1 receptor-expressing projection neurons. Cyclic adenosine monophosphate (cAMP) immunoassay and adenylyl cyclase activity assays were also performed. RESULTS In DYT1 and DYT6 models, blocking dopamine reuptake with cocaine leads to enhanced extracellular signal-related kinase phosphorylation in dorsomedial striatal medium spiny neurons in the direct pathway, which is abolished by pretreatment with the N-methyl-d-aspartate antagonist MK-801. Phosphorylation is decreased in a model of DYT25. Levels of basal and stimulated cAMP and adenylyl cyclase activity were normal in the DYT1 and DYT6 mice and decreased in the DYT25 mice. Oxotremorine induced increased abnormal movements in the DYT1 knock-in mice. CONCLUSIONS The increased dopamine induction of extracellular signal-related kinase phosphorylation in 2 genetic types of dystonia, similar to what occurs in levodopa-induced dyskinesia, and its decrease in a third, suggests that abnormal signal transduction in response to dopamine in the postsynaptic nigrostriatal pathway might be a point of convergence for dystonia and other hyperkinetic movement disorders, potentially offering common therapeutic targets. © 2021 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Chiara Melis
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Genevieve Beauvais
- Raymond G. Perelman Center for Cellular and Molecular Therapy, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Brian S Muntean
- Department of Neuroscience, The Scripps Research Institute, Jupiter, Florida, USA
| | - Maria-Daniela Cirnaru
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Garrett Otrimski
- Raymond G. Perelman Center for Cellular and Molecular Therapy, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Jordi Creus-Muncunill
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Kirill A Martemyanov
- Department of Neuroscience, The Scripps Research Institute, Jupiter, Florida, USA
| | - Pedro Gonzalez-Alegre
- Raymond G. Perelman Center for Cellular and Molecular Therapy, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.,Department of Neurology, The University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Michelle E Ehrlich
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Departments of Pediatrics and Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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4
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Mel1c Mediated Monochromatic Light-Stimulated IGF-I Synthesis through the Intracellular G αq/PKC/ERK Signaling Pathway. Int J Mol Sci 2019; 20:ijms20071682. [PMID: 30987295 PMCID: PMC6480035 DOI: 10.3390/ijms20071682] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 03/09/2019] [Accepted: 03/29/2019] [Indexed: 02/06/2023] Open
Abstract
Previous studies have demonstrated that monochromatic light affects plasma melatonin (MEL) levels, which in turn regulates hepatic insulin-like growth factor I (IGF-I) secretion via the Mel1c receptor. However, the intracellular signaling pathway initiated by Mel1c remains unclear. In this study, newly hatched broilers, including intact, sham operation, and pinealectomy groups, were exposed to either white (WL), red (RL), green (GL), or blue (BL) light for 14 days. Experiments in vivo showed that GL significantly promoted plasma MEL formation, which was accompanied by an increase in the MEL receptor, Mel1c, as well as phosphorylated extracellular regulated protein kinases (p-ERK1/2), and IGF-I expression in the liver, compared to the other light-treated groups. In contrast, this GL stimulation was attenuated by pinealectomy. Exogenous MEL elevated the hepatocellular IGF-I level, which is consistent with increases in cyclic adenosine monophosphate (cAMP), Gαq, phosphorylated protein kinase C (p-PKC), and p-ERK1/2 expression. However, the Mel1c selective antagonist prazosin suppressed the MEL-induced expression of IGF-I, Gαq, p-PKC, and p-ERK1/2, while the cAMP concentration was barely affected. In addition, pretreatment with Ym254890 (a Gαq inhibitor), Go9863 (a PKC inhibitor), and PD98059 (an ERK1/2 inhibitor) markedly attenuated MEL-stimulated IGF-I expression and p-ERK1/2 activity. These results indicate that Mel1c mediates monochromatic GL-stimulated IGF-I synthesis through intracellular Gαq/PKC/ERK signaling.
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5
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Lee BS, Lee C, Yang S, Park EK, Ku SK, Bae JS. Suppressive effects of pelargonidin on lipopolysaccharide-induced inflammatory responses. Chem Biol Interact 2019; 302:67-73. [DOI: 10.1016/j.cbi.2019.02.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Revised: 02/06/2019] [Accepted: 02/08/2019] [Indexed: 12/20/2022]
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Characterisation of small molecule ligands 4CMTB and 2CTAP as modulators of human FFA2 receptor signalling. Sci Rep 2018; 8:17819. [PMID: 30546040 PMCID: PMC6292860 DOI: 10.1038/s41598-018-36242-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 10/30/2018] [Indexed: 01/22/2023] Open
Abstract
Short chain fatty acids (SCFAs) are protective against inflammatory diseases. Free fatty acid receptor 2 (FFA2), is a target of SCFAs however, their selectivity for FFA2 over other FFA receptors is limited. This study aimed to functionally characterise 2-(4-chlorophenyl)-3-methyl-N-(thiazole-2-yl)butanamide (4CMTB) and 4-((4-(2-chlorophenyl)thiazole-2-yl)amino)-4oxo-3-phenylbutanoic acid (2CTAP), and their enantiomers, in modulating FFA2 activity. The racemic mixture (R/S) and its constituents (R-) and (S-) 4CMTB or 2CTAP were used to stimulate human (h)FFA2 in the absence or presence of acetate. Calcium ions (Ca2+), phosphorylated extracellular signal-regulated kinase 1 and 2 (pERK1/2) and cyclic adenosine monophosphate (cAMP) were measured. R/S-4CMTB is a functionally selective ago-allosteric ligand that enhances Ca2+ response to acetate. Both R/S-4CMTB and S-4CMTB are more potent activators of pERK1/2 and inhibitors of forskolin-induced cAMP than acetate. S-4CMTB increased neutrophil infiltration in intestinal ischemia reperfusion injury (IRI). 2CTAP inhibited constitutive Ca2+ levels, antagonised acetate-induced pERK1/2 and prevented damage following IRI. This study characterises enantiomers of functionally selective ligands for FFA2 in cells stably expressing hFFA2. It highlights the novel roles of selective FFA2 enantiomers 4CMTB and 2CTAP on Ca2+, pERK1/2 and cAMP and their roles as allosteric modulators which, may assist in efforts to design novel therapeutic agents for FFA2-driven inflammatory diseases.
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7
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Luttrell LM, Wang J, Plouffe B, Smith JS, Yamani L, Kaur S, Jean-Charles PY, Gauthier C, Lee MH, Pani B, Kim J, Ahn S, Rajagopal S, Reiter E, Bouvier M, Shenoy SK, Laporte SA, Rockman HA, Lefkowitz RJ. Manifold roles of β-arrestins in GPCR signaling elucidated with siRNA and CRISPR/Cas9. Sci Signal 2018; 11:11/549/eaat7650. [PMID: 30254056 DOI: 10.1126/scisignal.aat7650] [Citation(s) in RCA: 132] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
G protein-coupled receptors (GPCRs) use diverse mechanisms to regulate the mitogen-activated protein kinases ERK1/2. β-Arrestins (βArr1/2) are ubiquitous inhibitors of G protein signaling, promoting GPCR desensitization and internalization and serving as scaffolds for ERK1/2 activation. Studies using CRISPR/Cas9 to delete βArr1/2 and G proteins have cast doubt on the role of β-arrestins in activating specific pools of ERK1/2. We compared the effects of siRNA-mediated knockdown of βArr1/2 and reconstitution with βArr1/2 in three different parental and CRISPR-derived βArr1/2 knockout HEK293 cell pairs to assess the effect of βArr1/2 deletion on ERK1/2 activation by four Gs-coupled GPCRs. In all parental lines with all receptors, ERK1/2 stimulation was reduced by siRNAs specific for βArr2 or βArr1/2. In contrast, variable effects were observed with CRISPR-derived cell lines both between different lines and with activation of different receptors. For β2 adrenergic receptors (β2ARs) and β1ARs, βArr1/2 deletion increased, decreased, or had no effect on isoproterenol-stimulated ERK1/2 activation in different CRISPR clones. ERK1/2 activation by the vasopressin V2 and follicle-stimulating hormone receptors was reduced in these cells but was enhanced by reconstitution with βArr1/2. Loss of desensitization and receptor internalization in CRISPR βArr1/2 knockout cells caused β2AR-mediated stimulation of ERK1/2 to become more dependent on G proteins, which was reversed by reintroducing βArr1/2. These data suggest that βArr1/2 function as a regulatory hub, determining the balance between mechanistically different pathways that result in activation of ERK1/2, and caution against extrapolating results obtained from βArr1/2- or G protein-deleted cells to GPCR behavior in native systems.
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Affiliation(s)
- Louis M Luttrell
- Department of Medicine, Medical University of South Carolina, Charleston, SC 29425, USA.,Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC 29425, USA.,Research Service of the Ralph H. Johnson Veterans Affairs Medical Center, Charleston, SC 29401, USA
| | - Jialu Wang
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Bianca Plouffe
- Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, University of Montreal, Montreal, Quebec H3C IJ4, Canada
| | - Jeffrey S Smith
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA.,Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA
| | - Lama Yamani
- Department of Medicine, Research Institute of the McGill University Health Center, McGill University, Montreal, Quebec H4A 3J1, Canada
| | - Suneet Kaur
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | | | - Christophe Gauthier
- Physiologie de la Reproduction et des Comportements, Institut National de la Recherche Agronomique, CNRS, Université de Tours, 37380 Nouzilly, France
| | - Mi-Hye Lee
- Department of Medicine, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Biswaranjan Pani
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Jihee Kim
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Seungkirl Ahn
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Sudarshan Rajagopal
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA.,Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA
| | - Eric Reiter
- Physiologie de la Reproduction et des Comportements, Institut National de la Recherche Agronomique, CNRS, Université de Tours, 37380 Nouzilly, France
| | - Michel Bouvier
- Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, University of Montreal, Montreal, Quebec H3C IJ4, Canada
| | - Sudha K Shenoy
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA.,Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Stéphane A Laporte
- Department of Medicine, Research Institute of the McGill University Health Center, McGill University, Montreal, Quebec H4A 3J1, Canada
| | - Howard A Rockman
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA.,Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA.,Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Robert J Lefkowitz
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA. .,Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA.,Howard Hughes Medical Institute, Duke University Medical Center, Durham, NC 27710, USA
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8
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Laing BT, Li P, Schmidt CA, Bunner W, Yuan Y, Landry T, Prete A, McClung JM, Huang H. AgRP/NPY Neuron Excitability Is Modulated by Metabotropic Glutamate Receptor 1 During Fasting. Front Cell Neurosci 2018; 12:276. [PMID: 30233321 PMCID: PMC6129575 DOI: 10.3389/fncel.2018.00276] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 08/08/2018] [Indexed: 12/17/2022] Open
Abstract
The potential to control feeding behavior via hypothalamic AgRP/NPY neurons has led to many approaches to modulate their excitability—particularly by glutamatergic input. In the present study using NPY-hrGFP reporter mice, we visualize AgRP/NPY neuronal metabotropic glutamate receptor 1 (mGluR1) expression and test the effect of fasting on mGluR1 function. Using the pharmacological agonist dihydroxyphenylglycine (DHPG), we demonstrate the enhanced capacity of mGluR1 to drive firing of AgRP/NPY neurons after overnight fasting, while antagonist 3-MATIDA reduces firing. Further, under synaptic blockade we demonstrate that DHPG acts directly on AgRP/NPY neurons to create a slow inward current. Using an in vitro approach, we show that emulation of intracellular signals associated with fasting by forskolin enhances DHPG induced phosphorylation of extracellularly regulated-signal kinase (1/2) in GT1-7 cell culture. We show in vivo that blocking mGluR1 by antagonist 3-MATIDA lowers fasting induced refeeding. In summary, this study identifies a novel layer of regulation on AgRP/NPY neurons integrated with whole body energy balance.
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Affiliation(s)
- Brenton T Laing
- Human Performance Laboratory, Department of Kinesiology, East Carolina University, Greenville, NC, United States.,East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States
| | - Peixin Li
- Human Performance Laboratory, Department of Kinesiology, East Carolina University, Greenville, NC, United States.,East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States
| | - Cameron A Schmidt
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States.,Department of Physiology, East Carolina University, Greenville, NC, United States
| | - Wyatt Bunner
- Human Performance Laboratory, Department of Kinesiology, East Carolina University, Greenville, NC, United States.,East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States
| | - Yuan Yuan
- Human Performance Laboratory, Department of Kinesiology, East Carolina University, Greenville, NC, United States.,East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States
| | - Taylor Landry
- Human Performance Laboratory, Department of Kinesiology, East Carolina University, Greenville, NC, United States.,East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States
| | - Amber Prete
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States
| | - Joseph M McClung
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States.,Department of Physiology, East Carolina University, Greenville, NC, United States
| | - Hu Huang
- Human Performance Laboratory, Department of Kinesiology, East Carolina University, Greenville, NC, United States.,East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States.,Department of Physiology, East Carolina University, Greenville, NC, United States
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9
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Bower RL, Yule L, Rees TA, Deganutti G, Hendrikse ER, Harris PWR, Kowalczyk R, Ridgway Z, Wong AG, Swierkula K, Raleigh DP, Pioszak AA, Brimble MA, Reynolds CA, Walker CS, Hay DL. Molecular Signature for Receptor Engagement in the Metabolic Peptide Hormone Amylin. ACS Pharmacol Transl Sci 2018; 1:32-49. [PMID: 32219203 DOI: 10.1021/acsptsci.8b00002] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Indexed: 11/30/2022]
Abstract
The pancreatic peptide hormone, amylin, plays a critical role in the control of appetite, and synergizes with other key metabolic hormones such as glucagon-like peptide 1 (GLP-1). There is opportunity to develop potent and long-acting analogues of amylin or hybrids between these and GLP-1 mimetics for treating obesity. To achieve this, interrogation of how the 37 amino acid amylin peptide engages with its complex receptor system is required. We synthesized an extensive library of peptides to profile the human amylin sequence, determining the role of its disulfide loop, amidated C-terminus and receptor "capture" and "activation" regions in receptor signaling. We profiled four signaling pathways with different ligands at multiple receptor subtypes, in addition to exploring selectivity determinants between related receptors. Distinct roles for peptide subregions in receptor binding and activation were identified, resulting in peptides with greater activity than the native sequence. Enhanced peptide activity was preserved in the brainstem, the major biological target for amylin. Interpretation of our data using full-length active receptor models supported by molecular dynamics, metadynamics, and supervised molecular dynamics simulations guided the synthesis of a potent dual agonist of GLP-1 and amylin receptors. The data offer new insights into the function of peptide amidation, how allostery drives peptide-receptor interactions, and provide a valuable resource for the development of novel amylin agonists for treating diabetes and obesity.
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Affiliation(s)
- Rebekah L Bower
- School of Biological Sciences, School of Chemical Sciences, and Maurice Wilkins Centre, The University of Auckland, Auckland, 1010, New Zealand
| | - Lauren Yule
- School of Biological Sciences, School of Chemical Sciences, and Maurice Wilkins Centre, The University of Auckland, Auckland, 1010, New Zealand.,School of Biological Sciences, School of Chemical Sciences, and Maurice Wilkins Centre, The University of Auckland, Auckland, 1010, New Zealand.,School of Biological Sciences, School of Chemical Sciences, and Maurice Wilkins Centre, The University of Auckland, Auckland, 1010, New Zealand
| | - Tayla A Rees
- School of Biological Sciences, School of Chemical Sciences, and Maurice Wilkins Centre, The University of Auckland, Auckland, 1010, New Zealand
| | - Giuseppe Deganutti
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, U.K
| | - Erica R Hendrikse
- School of Biological Sciences, School of Chemical Sciences, and Maurice Wilkins Centre, The University of Auckland, Auckland, 1010, New Zealand
| | - Paul W R Harris
- School of Biological Sciences, School of Chemical Sciences, and Maurice Wilkins Centre, The University of Auckland, Auckland, 1010, New Zealand.,School of Biological Sciences, School of Chemical Sciences, and Maurice Wilkins Centre, The University of Auckland, Auckland, 1010, New Zealand.,School of Biological Sciences, School of Chemical Sciences, and Maurice Wilkins Centre, The University of Auckland, Auckland, 1010, New Zealand
| | - Renata Kowalczyk
- School of Biological Sciences, School of Chemical Sciences, and Maurice Wilkins Centre, The University of Auckland, Auckland, 1010, New Zealand.,School of Biological Sciences, School of Chemical Sciences, and Maurice Wilkins Centre, The University of Auckland, Auckland, 1010, New Zealand
| | - Zachary Ridgway
- Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States
| | - Amy G Wong
- Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States
| | - Katarzyna Swierkula
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, U.K
| | - Daniel P Raleigh
- Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States.,Department of Structural and Molecular Biology, University College London, London WC1E 6BT, U.K
| | - Augen A Pioszak
- Department of Biochemistry and Molecular Biology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, United States
| | - Margaret A Brimble
- School of Biological Sciences, School of Chemical Sciences, and Maurice Wilkins Centre, The University of Auckland, Auckland, 1010, New Zealand.,School of Biological Sciences, School of Chemical Sciences, and Maurice Wilkins Centre, The University of Auckland, Auckland, 1010, New Zealand
| | - Christopher A Reynolds
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, U.K
| | - Christopher S Walker
- School of Biological Sciences, School of Chemical Sciences, and Maurice Wilkins Centre, The University of Auckland, Auckland, 1010, New Zealand
| | - Debbie L Hay
- School of Biological Sciences, School of Chemical Sciences, and Maurice Wilkins Centre, The University of Auckland, Auckland, 1010, New Zealand.,School of Biological Sciences, School of Chemical Sciences, and Maurice Wilkins Centre, The University of Auckland, Auckland, 1010, New Zealand
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10
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Lee IC, Kim J, Bae JS. Anti-inflammatory effects of dabrafenib in vitro and in vivo. Can J Physiol Pharmacol 2017; 95:697-707. [DOI: 10.1139/cjpp-2016-0519] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The screening of bioactive compound libraries can be an effective approach for repositioning FDA-approved drugs or discovering new treatments for human diseases (drug repositioning). Drug repositioning refers to the development of existing drugs for new indications. Dabrafenib (DAB) is a B-Raf inhibitor and initially used for the treatment of metastatic melanoma therapy. Here, we tested the possible use of DAB in the treatment of lipopolysaccharide (LPS)-mediated vascular inflammatory responses. The anti-inflammatory activities of DAB were determined by measuring permeability, neutrophils adhesion and migration, and activation of pro-inflammatory proteins in LPS-activated human umbilical vein endothelial cells (HUVECs) and mice. We found that DAB inhibited LPS-induced barrier disruption, expression of cell adhesion molecules (CAMs), and adhesion and transendothelial migration of neutrophils to human endothelial cells. DAB also suppressed LPS-induced hyperpermeability and leukocytes migration in vivo. Furthermore, DAB suppressed the production of tumor necrosis factor-α (TNF-α) or interleukin (IL)-6 and the activation of nuclear factor-κB (NF-κB) or extracellular regulated kinases (ERK) 1/2 by LPS. Moreover, treatment with DAB resulted in reduced LPS-induced lethal endotoxemia. These results suggest that DAB possesses anti-inflammatory functions by inhibiting hyperpermeability, expression of CAMs, and adhesion and migration of leukocytes, thereby endorsing its usefulness as a therapy for vascular inflammatory diseases.
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Affiliation(s)
- In-Chul Lee
- Department of Cosmetic Science and Technology, Seowon University, Cheongju 28674, Republic of Korea
| | - Jongdoo Kim
- Cancer Control Team, Gachon University Gil Medical Center, Incheon 21565, Republic of Korea
| | - Jong-Sup Bae
- College of Pharmacy, CMRI, Research Institute of Pharmaceutical Sciences, BK21 Plus KNU Multi-Omics based Creative Drug Research Team, Kyungpook National University, Daegu 41566, Republic of Korea
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11
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Walker CS, Raddant AC, Woolley MJ, Russo AF, Hay DL. CGRP receptor antagonist activity of olcegepant depends on the signalling pathway measured. Cephalalgia 2017; 38:437-451. [PMID: 28165287 DOI: 10.1177/0333102417691762] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Background Calcitonin gene-related peptide (CGRP) is a neuropeptide that acts in the trigeminovascular system and is believed to play an important role in migraine. CGRP activates two receptors that are both present in the trigeminovascular system; the CGRP receptor and the amylin 1 (AMY1) receptor. CGRP receptor antagonists, including olcegepant (BIBN4096BS) and telcagepant (MK-0974), can treat migraine. This study aimed to determine the effectiveness of these antagonists at blocking CGRP receptor signalling in trigeminal ganglia (TG) neurons and transfected CGRP and AMY1 receptors in Cos7 cells, to better understand their mechanism of action. Methods CGRP stimulation of four intracellular signalling molecules relevant to pain (cAMP, CREB, p38 and ERK) were examined in rat TG neurons and compared to transfected CGRP and AMY1 receptors in Cos7 cells. Results In TG neurons, olcegepant displayed signal-specific differences in antagonism of CGRP responses. This effect was also evident in transfected Cos7 cells, where olcegepant blocked CREB phosphorylation more potently than expected at the AMY1 receptor, suggesting that the affinity of this antagonist can be dependent on the signalling pathway activated. Conclusions CGRP receptor antagonist activity appears to be assay-dependent. Thus, these molecules may not be as selective for the CGRP receptor as commonly reported.
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Affiliation(s)
- Christopher S Walker
- 1 School of Biological Sciences, University of Auckland, Auckland, New Zealand.,2 Centre for Brain Research, University of Auckland, Auckland, New Zealand
| | - Ann C Raddant
- 3 Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA, USA
| | - Michael J Woolley
- 4 Institute of Clinical Studies, University of Birmingham, Edgbaston, Birmingham, UK
| | - Andrew F Russo
- 3 Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA, USA.,5 Department of Neurology, University of Iowa; Veterans Affairs Medical Center, Iowa City, IA, USA
| | - Debbie L Hay
- 1 School of Biological Sciences, University of Auckland, Auckland, New Zealand.,2 Centre for Brain Research, University of Auckland, Auckland, New Zealand
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12
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Brust A, Croker DE, Colless B, Ragnarsson L, Andersson Å, Jain K, Garcia-Caraballo S, Castro J, Brierley SM, Alewood PF, Lewis RJ. Conopeptide-Derived κ-Opioid Agonists (Conorphins): Potent, Selective, and Metabolic Stable Dynorphin A Mimetics with Antinociceptive Properties. J Med Chem 2016; 59:2381-95. [PMID: 26859603 DOI: 10.1021/acs.jmedchem.5b00911] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Opioid receptor screening of a conopeptide library led to a novel selective κ-opioid agonist peptide (conorphin T). Intensive medicinal chemistry, guided by potency, selectivity, and stability assays generated a pharmacophore model supporting rational design of highly potent and selective κ-opioid receptor (KOR) agonists (conorphins) with exceptional plasma stability. Conorphins are defined by a hydrophobic benzoprolyl moiety, a double arginine sequence, a spacer amino acid followed by a hydrophobic residue and a C-terminal vicinal disulfide moiety. The pharmacophore model was supported by computational docking studies, revealing receptor-ligand interactions similar to KOR agonist dynorphin A (1-8). A conorphin agonist inhibited colonic nociceptors in a mouse tissue model of chronic visceral hypersensitivity, suggesting the potential of KOR agonists for the treatment of chronic abdominal pain. This new conorphine KOR agonist class and pharmacophore model provide opportunities for future rational drug development and probes for exploring the role of the κ-opioid receptor.
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Affiliation(s)
- Andreas Brust
- Xenome Limited , Brisbane, Queensland 4068, Australia.,Institute for Molecular Biosciences, The University of Queensland , Brisbane, Queensland, 4072, Australia
| | - Daniel E Croker
- Xenome Limited , Brisbane, Queensland 4068, Australia.,Institute for Molecular Biosciences, The University of Queensland , Brisbane, Queensland, 4072, Australia
| | - Barbara Colless
- Xenome Limited , Brisbane, Queensland 4068, Australia.,Institute for Molecular Biosciences, The University of Queensland , Brisbane, Queensland, 4072, Australia
| | - Lotten Ragnarsson
- Xenome Limited , Brisbane, Queensland 4068, Australia.,Institute for Molecular Biosciences, The University of Queensland , Brisbane, Queensland, 4072, Australia
| | - Åsa Andersson
- Xenome Limited , Brisbane, Queensland 4068, Australia.,Institute for Molecular Biosciences, The University of Queensland , Brisbane, Queensland, 4072, Australia
| | - Kapil Jain
- Institute for Molecular Biosciences, The University of Queensland , Brisbane, Queensland, 4072, Australia
| | - Sonia Garcia-Caraballo
- Visceral Pain Group, Centre for Nutrition and Gastrointestinal Disease, Discipline of Medicine, The University of Adelaide, South Australian Health and Medical Research Institute, SAHMRI , Adelaide, SA 5000, Australia
| | - Joel Castro
- Visceral Pain Group, Centre for Nutrition and Gastrointestinal Disease, Discipline of Medicine, The University of Adelaide, South Australian Health and Medical Research Institute, SAHMRI , Adelaide, SA 5000, Australia
| | - Stuart M Brierley
- Visceral Pain Group, Centre for Nutrition and Gastrointestinal Disease, Discipline of Medicine, The University of Adelaide, South Australian Health and Medical Research Institute, SAHMRI , Adelaide, SA 5000, Australia
| | - Paul F Alewood
- Institute for Molecular Biosciences, The University of Queensland , Brisbane, Queensland, 4072, Australia
| | - Richard J Lewis
- Xenome Limited , Brisbane, Queensland 4068, Australia.,Institute for Molecular Biosciences, The University of Queensland , Brisbane, Queensland, 4072, Australia
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13
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Lee W, Ku SK, Bae JS. Anti-inflammatory effects of Baicalin, Baicalein, and Wogonin in vitro and in vivo. Inflammation 2015; 38:110-25. [PMID: 25249339 DOI: 10.1007/s10753-014-0013-0] [Citation(s) in RCA: 127] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Here, three structurally related polyphenols found in the Chinese herb Huang Qui, namely baicalin, baicalein, and wogonin, were examined for its effects on inflammatory responses by monitoring the effects of baicalin, baicalein, and wogonin on lipopolysaccharide (LPS)-mediated vascular inflammatory responses. We found that each compound inhibited LPS-induced barrier disruption, expression of cell adhesion molecules (CAMs), and adhesion/transendothelial migration of monocytes to human endothelial cells. Each compound induced potent inhibition of phorbol-12-myristate 13-acetate and LPS-induced endothelial cell protein C receptor shedding. It also suppressed LPS-induced hyperpermeability and leukocytes migration in vivo. Furthermore, each compound suppressed the production of tumor necrosis factor-α or interleukin-6 and the activation of nuclear factor-κB or extracellular regulated kinases 1/2 by LPS. Moreover, treatment with each compound resulted in reduced LPS-induced lethal endotoxemia. These results suggest that baicalin, baicalein, and wogonin posses anti-inflammatory functions by inhibiting hyperpermeability, expression of CAMs, and adhesion and migration of leukocytes, thereby endorsing its usefulness as a therapy for vascular inflammatory diseases.
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Affiliation(s)
- Wonhwa Lee
- College of Pharmacy, CMRI, Research Institute of Pharmaceutical Sciences, Kyungpook National University, 80 Dahak-ro, Buk-gu, Daegu, 702-701, Republic of Korea
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14
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Anti-inflammatory effects of methylthiouracil in vitro and in vivo. Toxicol Appl Pharmacol 2015; 288:374-86. [DOI: 10.1016/j.taap.2015.08.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 07/25/2015] [Accepted: 08/14/2015] [Indexed: 01/11/2023]
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15
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Anti-inflammatory effects of vicenin-2 and scolymoside in vitro and in vivo. Inflamm Res 2015; 64:1005-21. [DOI: 10.1007/s00011-015-0886-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 09/28/2015] [Accepted: 10/06/2015] [Indexed: 12/21/2022] Open
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Frankowski KJ, Slauson SR, Lovell KM, Phillips AM, Streicher JM, Zhou L, Whipple DA, Schoenen FJ, Prisinzano TE, Bohn LM, Aubé J. Potency enhancement of the κ-opioid receptor antagonist probe ML140 through sulfonamide constraint utilizing a tetrahydroisoquinoline motif. Bioorg Med Chem 2015; 23:3948-56. [PMID: 25593096 PMCID: PMC4468036 DOI: 10.1016/j.bmc.2014.12.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Revised: 12/12/2014] [Accepted: 12/16/2014] [Indexed: 11/23/2022]
Abstract
Optimization of the sulfonamide-based kappa opioid receptor (KOR) antagonist probe molecule ML140 through constraint of the sulfonamide nitrogen within a tetrahydroisoquinoline moiety afforded a marked increase in potency. This strategy, when combined with additional structure-activity relationship exploration, has led to a compound only six-fold less potent than norBNI, a widely utilized KOR antagonist tool compound, but significantly more synthetically accessible. The new optimized probe is suitably potent for use as an in vivo tool to investigate the therapeutic potential of KOR antagonists.
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Affiliation(s)
- Kevin J Frankowski
- University of Kansas Specialized Chemistry Center, 2034 Becker Drive, Lawrence, KS 66047-3761, USA
| | - Stephen R Slauson
- University of Kansas Specialized Chemistry Center, 2034 Becker Drive, Lawrence, KS 66047-3761, USA
| | - Kimberly M Lovell
- Departments of Molecular Therapeutics and Neuroscience, The Scripps Research Institute, 130 Scripps Way, #2A2, Jupiter, FL 33458, USA
| | - Angela M Phillips
- Departments of Molecular Therapeutics and Neuroscience, The Scripps Research Institute, 130 Scripps Way, #2A2, Jupiter, FL 33458, USA
| | - John M Streicher
- Departments of Molecular Therapeutics and Neuroscience, The Scripps Research Institute, 130 Scripps Way, #2A2, Jupiter, FL 33458, USA
| | - Lei Zhou
- Departments of Molecular Therapeutics and Neuroscience, The Scripps Research Institute, 130 Scripps Way, #2A2, Jupiter, FL 33458, USA
| | - David A Whipple
- University of Kansas Specialized Chemistry Center, 2034 Becker Drive, Lawrence, KS 66047-3761, USA
| | - Frank J Schoenen
- University of Kansas Specialized Chemistry Center, 2034 Becker Drive, Lawrence, KS 66047-3761, USA
| | - Thomas E Prisinzano
- University of Kansas Specialized Chemistry Center, 2034 Becker Drive, Lawrence, KS 66047-3761, USA
| | - Laura M Bohn
- Departments of Molecular Therapeutics and Neuroscience, The Scripps Research Institute, 130 Scripps Way, #2A2, Jupiter, FL 33458, USA.
| | - Jeffrey Aubé
- University of Kansas Specialized Chemistry Center, 2034 Becker Drive, Lawrence, KS 66047-3761, USA.
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17
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Lee W, Bae JS. Anti-inflammatory Effects of Aspalathin and Nothofagin from Rooibos (Aspalathus linearis) In Vitro and In Vivo. Inflammation 2015; 38:1502-16. [DOI: 10.1007/s10753-015-0125-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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18
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Sakurai T, Koike T, Nakayama M. Pharmacological characterization of a highly selective and potent partial agonist of the MT₂ melatonin receptor. Pharmacology 2014; 93:244-52. [PMID: 25059758 DOI: 10.1159/000362561] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 03/31/2014] [Indexed: 11/19/2022]
Abstract
BACKGROUND/AIMS The MT₂ melatonin receptor is a potential target for treating circadian rhythm sleep disorders. This study aims to characterize the recently identified MT₂ melatonin receptor agonist. METHODS The pharmacological properties of the MT₂ melatonin receptor-selective agonist as exemplified by compound 1 [N-(2-[7-benzyl-1,6-dihydro-2H-indeno(5,4-b)furan-8-yl]ethyl)acetamide] were evaluated by use of cell-free binding and cell-based functional assays. RESULTS Competition binding assays using 2-[(125)I]iodomelatonin revealed rapid, reversible, and high-affinity binding of compound 1 to human, mouse, and rat MT₂ melatonin receptors. cAMP, ERK1/2, and PathHunter β-arrestin recruitment assays revealed partial agonist activities. However, compound 1 induced a more intense internalization of human MT₂ melatonin receptor than melatonin. Based on studies using structurally related analogs of compound 1, we further demonstrated that the extent of internalization is independent of the intrinsic efficacy of agonists. CONCLUSION These findings provide novel insights into the relationship between intrinsic agonist efficacy and agonist-induced internalization and demonstrate that compound 1 could serve as a pharmacological tool for future studies to elucidate the detailed molecular mechanism of MT₂ receptor internalization.
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Affiliation(s)
- Taku Sakurai
- Biomolecular Research Laboratories, Pharmaceutical Research Division, Takeda Pharmaceutical Company Ltd., Fujisawa, Japan
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20
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Lee W, Ku SK, Bae JS. Vascular barrier protective effects of orientin and isoorientin in LPS-induced inflammation in vitro and in vivo. Vascul Pharmacol 2014; 62:3-14. [DOI: 10.1016/j.vph.2014.04.006] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 04/12/2014] [Accepted: 04/18/2014] [Indexed: 01/11/2023]
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21
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Ayoub MA, Trebaux J, Vallaghe J, Charrier-Savournin F, Al-Hosaini K, Gonzalez Moya A, Pin JP, Pfleger KDG, Trinquet E. Homogeneous time-resolved fluorescence-based assay to monitor extracellular signal-regulated kinase signaling in a high-throughput format. Front Endocrinol (Lausanne) 2014; 5:94. [PMID: 25002860 PMCID: PMC4066300 DOI: 10.3389/fendo.2014.00094] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2014] [Accepted: 06/04/2014] [Indexed: 01/14/2023] Open
Abstract
The extracellular signal-regulated kinases (ERKs) are key components of multiple important cell signaling pathways regulating diverse biological responses. This signaling is characterized by phosphorylation cascades leading to ERK1/2 activation and promoted by various cell surface receptors including G protein-coupled receptors (GPCRs) and receptor tyrosine kinases (RTKs). We report the development of a new cell-based Phospho-ERK1/2 assay (designated Phospho-ERK), which is a sandwich proximity-based assay using the homogeneous time-resolved fluorescence technology. We have validated the assay on endogenously expressed ERK1/2 activated by the epidermal growth factor as a prototypical RTK, as well as various GPCRs belonging to different classes and coupling to different heterotrimeric G proteins. The assay was successfully miniaturized in 384-well plates using various cell lines endogenously, transiently, or stably expressing the different receptors. The validation was performed for agonists, antagonists, and inhibitors in dose-response as well as kinetic analysis, and the signaling and pharmacological properties of the different receptors were reproduced. Furthermore, the determination of a Z'-factor value of 0.7 indicates the potential of the Phospho-ERK assay for high-throughput screening of compounds that may modulate ERK1/2 signaling. Finally, our study is of great interest in the current context of investigating ERK1/2 signaling with respect to the emerging concepts of biased ligands, G protein-dependent/independent ERK1/2 activation, and functional transactivation between GPCRs and RTKs, illustrating the importance of considering the ERK1/2 pathway in cell signaling.
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Affiliation(s)
- Mohammed Akli Ayoub
- Molecular Endocrinology and Pharmacology, Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Nedlands, WA, Australia
| | | | | | | | - Khaled Al-Hosaini
- Department of Molecular Pharmacology, CNRS UMR5203, INSERM U661, Institute of Functional Genomics, Universities Montpellier 1 & 2, Montpellier, France
| | | | - Jean-Philippe Pin
- Department of Molecular Pharmacology, CNRS UMR5203, INSERM U661, Institute of Functional Genomics, Universities Montpellier 1 & 2, Montpellier, France
| | - Kevin D. G. Pfleger
- Molecular Endocrinology and Pharmacology, Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Nedlands, WA, Australia
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Lee W, Ku SK, Min BW, Lee S, Jee JG, Kim JA, Bae JS. Vascular barrier protective effects of pellitorine in LPS-induced inflammation in vitro and in vivo. Fitoterapia 2013; 92:177-87. [PMID: 24262867 DOI: 10.1016/j.fitote.2013.11.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Revised: 11/06/2013] [Accepted: 11/09/2013] [Indexed: 12/22/2022]
Abstract
Pellitorine (PT), an active amide compound, is well known to possess insecticidal, antibacterial and anticancer properties. In this study, we first investigated the possible barrier protective effects of pellitorine against pro-inflammatory responses induced by lipopolysaccharide (LPS) and the associated signaling pathways in vitro and in vivo. The barrier protective activities of PT were determined by measuring permeability, monocyte adhesion and migration, and activation of pro-inflammatory proteins in LPS-activated human umbilical vein endothelial cells (HUVECs) and in mice. We found that PT inhibited LPS-induced barrier disruption, expression of cell adhesion molecules (CAMs) and adhesion/transendothelial migration of monocytes to human endothelial cells. PT also suppressed LPS-induced hyperpermeability and leukocyte migration in vivo. Further studies revealed that PT suppressed the production of tumor necrosis factor-α (TNF-α) or Interleukin (IL)-6 and activation of nuclear factor-κB (NF-κB) or extracellular regulated kinases (ERK) 1/2 by LPS. Moreover, treatment with PT resulted in reduced LPS-induced lethal endotoxemia. These results suggest that PT protects vascular barrier integrity by inhibiting hyperpermeability, expression of CAMs, and adhesion and migration of leukocytes, thereby endorsing its usefulness as a therapy for vascular inflammatory diseases.
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Affiliation(s)
- Wonhwa Lee
- College of Pharmacy, CMRI, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 702-701, Republic of Korea; Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University, Daegu 702-701, Republic of Korea
| | - Sae-Kwang Ku
- Department of Anatomy and Histology, College of Korean Medicine, Daegu Haany University, Gyeongsan 712-715, Republic of Korea
| | - Byung-Woon Min
- Department of BioMedical Clinical Pathology, Hanlyo University, Gwangyang 545-704, Republic of Korea
| | - Sangkyu Lee
- College of Pharmacy, CMRI, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 702-701, Republic of Korea
| | - Jun-Goo Jee
- College of Pharmacy, CMRI, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 702-701, Republic of Korea
| | - Jeong Ah Kim
- College of Pharmacy, CMRI, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 702-701, Republic of Korea
| | - Jong-Sup Bae
- College of Pharmacy, CMRI, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 702-701, Republic of Korea.
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George AJ, Hannan RD, Thomas WG. Unravelling the molecular complexity of GPCR-mediated EGFR transactivation using functional genomics approaches. FEBS J 2013; 280:5258-68. [PMID: 23992425 DOI: 10.1111/febs.12509] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Revised: 08/20/2013] [Accepted: 08/23/2013] [Indexed: 02/06/2023]
Abstract
To influence physiology and pathophysiology, G protein-coupled receptors (GPCRs) have evolved to appropriate additional signalling modalities, such as activation of adjacent membrane receptors. Epidermal growth factor receptors (EGFRs) mediate growth and remodelling actions of GPCRs, although the precise network of gene products and molecular cascades linking GPCRs to EGFRs (termed EGFR transactivation) remains incomplete. In this review, we describe the current view of GPCR-EGFR transactivation, identifying the established models of receptor cross-talk. We consider the limitations in our current knowledge, and propose that recent advances in molecular and cell biology technology, including functional genomics approaches, will allow a renewed focus of efforts to understand the mechanism underlying EGFR transactivation. Using an unbiased approach for identification of the molecules required for GPCR-mediated EGFR transactivation will provide a contemporary and more complete representation from which to extrapolate therapeutic control in diseases from cardiovascular remodelling to cancer.
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Affiliation(s)
- Amee J George
- School of Biomedical Sciences, The University of Queensland, St Lucia, Qld, Australia; Oncogenic Signalling and Growth Control Program, Peter MacCallum Cancer Centre, East Melbourne, Vic., Australia; Department of Pathology, The University of Melbourne, Parkville, Vic., Australia
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George AJ, Purdue BW, Gould CM, Thomas DW, Handoko Y, Qian H, Quaife-Ryan GA, Morgan KA, Simpson KJ, Thomas WG, Hannan RD. A functional siRNA screen identifies genes modulating angiotensin II-mediated EGFR transactivation. J Cell Sci 2013; 126:5377-90. [PMID: 24046455 DOI: 10.1242/jcs.128280] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The angiotensin type 1 receptor (AT1R) transactivates the epidermal growth factor receptor (EGFR) to mediate cellular growth, however, the molecular mechanisms involved have not yet been resolved. To address this, we performed a functional siRNA screen of the human kinome in human mammary epithelial cells that demonstrate a robust AT1R-EGFR transactivation. We identified a suite of genes encoding proteins that both positively and negatively regulate AT1R-EGFR transactivation. Many candidates are components of EGFR signalling networks, whereas others, including TRIO, BMX and CHKA, have not been previously linked to EGFR transactivation. Individual knockdown of TRIO, BMX or CHKA attenuated tyrosine phosphorylation of the EGFR by angiotensin II stimulation, but this did not occur following direct stimulation of the EGFR with EGF, indicating that these proteins function between the activated AT1R and the EGFR. Further investigation of TRIO and CHKA revealed that their activity is likely to be required for AT1R-EGFR transactivation. CHKA also mediated EGFR transactivation in response to another G protein-coupled receptor (GPCR) ligand, thrombin, indicating a pervasive role for CHKA in GPCR-EGFR crosstalk. Our study reveals the power of unbiased, functional genomic screens to identify new signalling mediators important for tissue remodelling in cardiovascular disease and cancer.
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Affiliation(s)
- Amee J George
- School of Biomedical Sciences, The University of Queensland, St. Lucia, Queensland, 4072, Australia
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Lee W, Yoo H, Kim JA, Lee S, Jee JG, Lee MY, Lee YM, Bae JS. Barrier protective effects of piperlonguminine in LPS-induced inflammation in vitro and in vivo. Food Chem Toxicol 2013; 58:149-57. [PMID: 23619565 DOI: 10.1016/j.fct.2013.04.027] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2013] [Revised: 03/27/2013] [Accepted: 04/12/2013] [Indexed: 01/04/2023]
Abstract
Piperlonguminine (PL), an important component of Piper longum fruits, is well known to possess potent anti-hyperlipidemic, anti-platelet and anti-melanogenesis activities. In this study, we first investigated the possible barrier protective effects of piperlonguminine against proinflammatory responses induced by lipopolysaccharide (LPS) and the associated signaling pathways in vitro and in vivo. The barrier protective activities of PL were determined by measuring permeability, monocytes adhesion and migration, and activation of proinflammatory proteins in LPS-activated human umbilical vein endothelial cells (HUVECs) and in mice. We found that PL inhibited LPS-induced barrier disruption, expression of cell adhesion molecules (CAMs) and adhesion/transendothelial migration of monocytes to human endothelial cells. PL also suppressed LPS-induced hyperpermeability and leukocytes migration in vivo. Further studies revealed that PL suppressed the production of tumor necrosis factor-α (TNF-α) or Interleukin (IL)-6 and activation of nuclear factor-κB (NF-κB) or extracellular regulated kinases (ERK) 1/2 by LPS. Moreover, treatment with PL resulted in reduced LPS-induced septic mortality. Collectively, these results suggest that PL protects vascular barrier integrity by inhibiting hyperpermeability, expression of CAMs, adhesion and migration of leukocytes, thereby endorsing its usefulness as a therapy for vascular inflammatory diseases.
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Affiliation(s)
- Wonhwa Lee
- College of Pharmacy, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 702-701, Republic of Korea
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Eishingdrelo H, Kongsamut S. Minireview: Targeting GPCR Activated ERK Pathways for Drug Discovery. Curr Chem Genom Transl Med 2013; 7:9-15. [PMID: 24396730 PMCID: PMC3854659 DOI: 10.2174/2213988501307010009] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Revised: 04/08/2013] [Accepted: 04/15/2013] [Indexed: 02/07/2023] Open
Abstract
It has become clear in recent years that multiple signal transduction pathways are employed upon GPCR
activation. One of the major cellular effectors activated by GPCRs is extracellular signal-regulated kinase (ERK). Both G-protein and β-arrestin mediated signaling pathways can lead to ERK activation. However, depending on activation
pathway, the subcellular destination of activated ERK1/2 may be different. G-protein -dependent ERK activation results in the translocation of active ERK to the nucleus, whereas ERK activated via an arrestin-dependent mechanism remains largely in the cytoplasm. The subcellular location of activated ERK1/2 determines the downstream signaling cascade. Many substrates of ERK1/2 are found in the nucleus: nuclear transcription factors that participate in gene transcription, cell proliferation and differentiation. ERK1/2 substrates are also found in cytosol and other cellular organelles: they may play roles in translation, mitosis, apoptosis and cross-talk with other signaling pathways. Therefore, determining specific subcellular locations of activated ERK1/2 mediated by GPCR ligands would be important in correlating signaling pathways with cellular physiological functions. While GPCR-stimulated selective ERK pathway activation has been studied in several receptor systems, exploitation of these different signaling cascades for therapeutics has not yet been seriously
pursued. Many old drug candidates were identified from screens based on G-protein signaling assays, and their activity on β-arrestin signaling pathways being mostly unknown, especially regarding their subcellular ERK pathways. With today’s knowledge of complicated GPCR signaling pathways, drug discovery can no longer rely on single-pathway approaches. Since ERK activation is an important signaling pathway and associated with many physiological functions, targeting the ERK pathway, especially specific subcellular activation pathways should provide new avenues for GPCR drug discovery.
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Affiliation(s)
- Haifeng Eishingdrelo
- BioInvenu Corporation, 50 Williams Parkway, East Hanover, New Jersey, 07936, USA
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Abstract
BACKGROUND Homogeneous time-resolved fluorescence (HTRF) is a fluorescence resonance energy transfer-based technology used to measure bimolecular interactions. It has been applied successfully to kinase assays and has become an important tool in kinase drug discovery. OBJECTIVE This article reviews the current status of HTRF technology in biochemical and cellular kinase assays. METHODS Recent literature and meeting reports on HTRF kinase assays are reviewed, and their principles, advantages and drawbacks, current status and the potential applications in kinase drug discovery are discussed. RESULTS/CONCLUSION HTRF kinase assays are homogeneous, robust, sensitive, easy to miniaturize and high-throughput. This assay format is versatile, as both peptide and protein substrates can be used, and high ATP concentrations are tolerated, which enables the assay to be performed under conditions mimicking the physiological environment. HTRF kinase assays have been applied to both high-throughput screening and compound mechanistic studies. Besides protein kinases, the technology has now been expanded into the lipid kinase family. Furthermore, the utility of HTRF technology in cellular assays is emerging. HTRF kinase assays are a great addition to the toolbox for kinase drug discovery.
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Affiliation(s)
- Yong Jia
- Group Leader Genomics Institute of the Novartis Research Foundation, Department of Kinase Biology, 10675 John J Hopkins Dr, San Diego, CA 92121, USA +858 812 1728 ; +858 812 1918 ;
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McLoughlin D, Bertelli F, Williams C. The A, B, Cs of G-protein-coupled receptor pharmacology in assay development for HTS. Expert Opin Drug Discov 2013; 2:603-19. [PMID: 23488953 DOI: 10.1517/17460441.2.5.603] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
G-protein-coupled receptors represent one of the most important areas of research in the pharmaceutical industry, being one of the largest druggable gene families. Recognising this fact, manufacturers have developed a huge variety of homogeneous assay technologies that facilitate the quantification of receptor ligand binding events and their downstream signalling cascades. However, while early emphasis was placed on the most sensitive, high-throughput and cost-effective screening technologies to enable identification of the most lead matter for further development, in recent years emphasis has shifted to a focus on maximising the identification of compounds that are new and developing assays that are more biologically/pharmacologically relevant. Therefore, this review provides an overview of the binding and functional techniques available for high-throughput screening, with particular attention on how assay application and configuration can be maximised to ensure their successful identification of relevant chemical matter and thereby optimising project success.
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Affiliation(s)
- Dj McLoughlin
- HTS CoE, Pfizer Global Research and Development, Ramsgate Road, Sandwich, Kent, CT13 9NJ, UK +44(0)1304644616 ; +44(0)1304655592 ;
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Klein MT, Vinson PN, Niswender CM. Approaches for probing allosteric interactions at 7 transmembrane spanning receptors. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 115:1-59. [PMID: 23415091 PMCID: PMC5482179 DOI: 10.1016/b978-0-12-394587-7.00001-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In recent years, allosteric modulation of 7 transmembrane spanning receptors (7TMRs) has become a highly productive and exciting field of receptor pharmacology and drug discovery efforts. Positive and negative allosteric modulators (PAMs and NAMs, respectively) present a number of pharmacological and therapeutic advantages over conventional orthosteric ligands, including improved receptor-subtype selectivity, a lower propensity to induce receptor desensitization, the preservation of endogenous temporal and spatial activation of receptors, greater chemical flexibility for optimization of drug metabolism and pharmacokinetic parameters, and saturability of effect at target receptors, thus improving safety concerns and risk of overdose. Additionally, the relatively new concept of allosteric modulator-mediated receptor signal bias opens up a number of intriguing possibilities for PAMs, NAMs, and allosteric agonists, including the potential to selectively activate therapeutically beneficial signaling cascades, which could yield a superior tissue selectivity and side effect profile of allosteric modulators. However, there are a number of considerations and caveats that must be addressed when screening for and characterizing the properties of 7TMR allosteric modulators. Mode of pharmacology, methodology used to monitor receptor activity, detection of appropriate downstream analytes, selection of orthosteric probe, and assay time-course must all be considered when implementing any high-throughput screening campaign or when characterizing the properties of active compounds. Yet compared to conventional agonist/antagonist drug discovery programs, these elements of assay design are often a great deal more complicated when working with 7TMRs allosteric modulators. Moreover, for classical pharmacological methodologies and analyses, like radioligand binding and the assessment of compound affinity, the properties of allosteric modulators yield data that are more nuanced than orthosteric ligand-receptor interactions. In this review, we discuss the current methodologies being used to identify and characterize allosteric modulators, lending insight into the approaches that have been most successful in accurately and robustly identifying hit compounds. New label-free technologies capable of detecting phenotypic cellular changes in response to receptor activation are powerful tools well suited for assessing subtle or potentially masked cellular responses to allosteric modulation of 7TMRs. Allosteric modulator-induced receptor signal bias and the assay systems available to probe the various downstream signaling outcomes of receptor activation are also discussed.
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Affiliation(s)
- Michael T Klein
- Department of Pharmacology, Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, Tennessee, USA
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Kenakin T. Casting a wider net: whole-cell assays to capture varied and biased signaling. Mol Pharmacol 2012; 82:571-4. [PMID: 22828801 DOI: 10.1124/mol.112.081117] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The observation of complex receptor behaviors has shown how ligands can have multiple efficacies and can also differentially stimulate certain cellular signaling pathways over others (i.e., biased signaling). Conventional pharmacological assays (usually proximal to the receptor) will detect ligands that produce the signal defined by the assay (i.e., Ca²⁺, cAMP, and others) but otherwise may miss biased ligands that produce little activation of pathways not measured by the assay. In theory, this is less of a hazard for generic whole-cell assays, which may be sensitive to multiple signaling inputs. Whole-cell assays have the advantage of detecting effects induced by a variety of receptor interactions with cytosolic proteins, including those that may be previously unknown. These ideas are discussed within the context of the high-throughput flow cytometry measurement of receptor internalization described by Wu et al. in the current issue of the journal. The internalization of receptors can be a useful therapeutic modality and the article by Wu et al. illustrates how this new assay, targeted to downstream cellular effects, can uncover unique ligand efficacies linked to receptor internalization.
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Affiliation(s)
- Terry Kenakin
- Department of Pharmacology, University of North Carolina School of Medicine, 120 Mason Farm Rd., Room 4042 Genetic Medicine Building, CB#7365, Chapel Hill, NC 27599-7365, USA.
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Osmond RIW, Martin-Harris MH, Crouch MF, Park J, Morreale E, Dupriez VJ. G-Protein-Coupled Receptor-Mediated MAPK and PI3-Kinase Signaling Is Maintained in Chinese Hamster Ovary Cells after γ-Irradiation. ACTA ACUST UNITED AC 2011; 17:361-9. [DOI: 10.1177/1087057111425859] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
To expedite G-protein-coupled receptor (GPCR) drug screening studies, cell lines amenable to transfection (e.g. CHO cells) have been widely used as cellular models. These cells can be frozen in a ready-to-use format, allowing screening of a single batch of cells and validation of the cellular material prior to the screening run. A common method used to deliver frozen cells to screening programs is to γ-irradiate the cells, abrogating cell division after thawing and ensuring consistency in the number of cells analyzed per well. With the recognition that signaling proteins such as ERK and Akt are important markers of GPCR activation, along with the availability of suitable assays for their measurement, these outputs have become important for GPCR screening programs. Here we show that several γ-irradiated and frozen CHO-K1 cell lines expressing transfected GPCRs, initially optimized for performing cAMP or AequoScreen calcium flux assays, can be used for the measurement of GPCR-mediated ERK and Akt phosphorylation. Furthermore, CHO-K1 cells transfected with NOP or GAL1 receptors show pharmacology for a number of agonists and antagonists that is consistent with non-irradiated cultured lines. These data indicate that γ-irradiated CHO-K1 cells can be reliably used for the measurement of GPCR-mediated kinase signaling outputs.
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Trowitzsch S, Klumpp M, Thoma R, Carralot JP, Berger I. Light it up: highly efficient multigene delivery in mammalian cells. Bioessays 2011; 33:946-55. [PMID: 22002169 DOI: 10.1002/bies.201100109] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Multigene delivery and expression systems are emerging as key technologies for many applications in contemporary biology. We have developed new methods for multigene delivery and expression in eukaryotic hosts for a variety of applications, including production of protein complexes for structural biology and drug development, provision of multicomponent protein biologics, and cell-based assays. We implemented tandem recombineering to facilitate rapid generation of multicomponent gene expression constructs for efficient transformation of mammalian cells, resulting in homogenous cell populations. Analysis of multiple parameters in living cells may require co-expression of fluorescently tagged sensors simultaneously in a single cell, at defined and ideally controlled ratios. Our method enables such applications by overcoming currently limiting challenges. Here, we review recent multigene delivery and expression strategies and their exploitation in mammalian cells. We discuss applications in drug discovery assays, interaction studies, and biologics production, which may benefit in the future from our novel approach.
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Sava A, Formaggio E, Carignani C, Andreetta F, Bettini E, Griffante C. NMDA-induced ERK signalling is mediated by NR2B subunit in rat cortical neurons and switches from positive to negative depending on stage of development. Neuropharmacology 2011; 62:925-32. [PMID: 22001284 DOI: 10.1016/j.neuropharm.2011.09.025] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2010] [Revised: 09/23/2011] [Accepted: 09/25/2011] [Indexed: 10/16/2022]
Abstract
It is known that NMDA receptor stimulation can activate or inhibit the extracellular signal-regulated kinase (ERK) signalling cascade, a key pathway involved in neuronal plasticity and survival. However, the specific subtype(s) of NMDA receptor that exert bi-directional regulation of ERK signalling is under debate. Here we show that in young neurons (7-9 days in vitro, DIV), NMDA activated ERK signalling. In mature neurons (14-16 DIV), NMDA-evoked, in coincidence with a concentration-dependent increase in intracellular Ca(2+) ([Ca(2+)](i)), an increase in ERK phosphorylation at low concentrations (1-30 μM) while an inhibition at high concentrations (30 μM-250 μM). In more mature neurons (21-23 DIV) NMDA inhibited ERK signalling. Both activation and inhibition of ERK signalling were fully reversed by the selective NR2B receptor antagonists Ro 25-6981 and ifenprodil. Thus, the NR2B subunit can be both negatively or positively coupled to ERK signalling in rat cortical neurons, depending on their stage of development. This article is part of a Special Issue entitled 'Post-Traumatic Stress Disorder'.
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Affiliation(s)
- Anna Sava
- Department of Molecular and Cellular Biology, Neurosciences Centre of Excellence in Drug Discovery, GlaxoSmithKline R&D, 37135 Verona, Italy.
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Trinquet E, Bouhelal R, Dietz M. Monitoring Gq-coupled receptor response through inositol phosphate quantification with the IP-One assay. Expert Opin Drug Discov 2011; 6:981-94. [DOI: 10.1517/17460441.2011.608658] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Taouji S, Dahan S, Bossé R, Chevet E. Current Screens Based on the AlphaScreen Technology for Deciphering Cell Signalling Pathways. Curr Genomics 2011; 10:93-101. [PMID: 19794881 PMCID: PMC2699825 DOI: 10.2174/138920209787847041] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2009] [Revised: 01/08/2009] [Accepted: 01/20/2009] [Indexed: 11/22/2022] Open
Abstract
Global deciphering of signal transduction pathways represents a new challenge of the post-genomic era. However, for the majority of these signaling pathways the role(s), the function(s) and the interaction(s) of the signaling intermediates remain to be characterized in an integrated fashion. The global molecular study of cell signaling pathways and networks consequently requires sensitive, robust technologies which may allow in addition multi-parallel and highthroughput applications. The Alphascreen™ technology, relying on a bead-based homogenous approach, constitutes a valuable tool to detect and quantify a wide range of signaling events such as enzymatic activities or biomolecular interactions. In this article, we exhaustively review the literature and report the broad spectrum of Alphascreen™-based applications in the study of signal transduction pathways.
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Allen JA, Roth BL. Strategies to discover unexpected targets for drugs active at G protein-coupled receptors. Annu Rev Pharmacol Toxicol 2011; 51:117-44. [PMID: 20868273 DOI: 10.1146/annurev-pharmtox-010510-100553] [Citation(s) in RCA: 163] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
G protein-coupled receptors (GPCRs) are an evolutionarily conserved family of signaling molecules comprising approximately 2% of the human genome; this receptor family remains a central focus in basic pharmacology studies and drug discovery efforts. Detailed studies of drug action at GPCRs over the past decade have revealed existing and novel ligands that exhibit polypharmacology-that is, drugs with activity at more than one receptor target for which they were designed. These "off-target" drug actions can be a liability that causes adverse side effects; however, in several cases, drugs with less selectivity demonstrate better clinical efficacy. Here we review physical screening and cheminformatic approaches that define drug activity at the GPCR receptorome. In many cases, such profiling has revealed unexpected targets that explain therapeutic actions as well as off-targets underlying drug side effects. Such drug-receptor profiling has also provided new insights into mechanisms of action of existing drugs and has suggested directions for future drug development.
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Affiliation(s)
- John A Allen
- Department of Pharmacology, University of North Carolina, Chapel Hill, 27599, USA
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Venkatesh M, Wang H, Cayer J, Leroux M, Salvail D, Das B, Wrobel JE, Mani S. In vivo and in vitro characterization of a first-in-class novel azole analog that targets pregnane X receptor activation. Mol Pharmacol 2011; 80:124-35. [PMID: 21464197 DOI: 10.1124/mol.111.071787] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The pregnane X receptor (PXR) is a master regulator of xenobiotic clearance and is implicated in deleterious drug interactions (e.g., acetaminophen hepatotoxicity) and cancer drug resistance. However, small-molecule targeting of this receptor has been difficult; to date, directed synthesis of a relatively specific PXR inhibitor has remained elusive. Here we report the development and characterization of a first-in-class novel azole analog [1-(4-(4-(((2R,4S)-2-(2,4-difluorophenyl)-2-methyl-1,3-dioxolan-4-yl)methoxy)phenyl)piperazin-1-yl)ethanone (FLB-12)] that antagonizes the activated state of PXR with limited effects on other related nuclear receptors (i.e., liver X receptor, farnesoid X receptor, estrogen receptor α, peroxisome proliferator-activated receptor γ, and mouse constitutive androstane receptor). We investigated the toxicity and PXR antagonist effect of FLB-12 in vivo. Compared with ketoconazole, a prototypical PXR antagonist, FLB-12 is significantly less toxic to hepatocytes. FLB-12 significantly inhibits the PXR-activated loss of righting reflex to 2,2,2-tribromoethanol (Avertin) in vivo, abrogates PXR-mediated resistance to 7-ethyl-10-hydroxycamptothecin (SN-38) in colon cancer cells in vitro, and attenuates PXR-mediated acetaminophen hepatotoxicity in vivo. Thus, relatively selective targeting of PXR by antagonists is feasible and warrants further investigation. This class of agents is suitable for development as chemical probes of PXR function as well as potential PXR-directed therapeutics.
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Affiliation(s)
- Madhukumar Venkatesh
- Albert Einstein Cancer Center, Albert Einstein College of Medicine, New York, New York, USA
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Chiu CC, Chen BH, Hour TC, Chiang WF, Wu YJ, Chen CY, Chen HR, Chan PT, Liu SY, Chen JYF. Betel quid extract promotes oral cancer cell migration by activating a muscarinic M4 receptor-mediated signaling cascade involving SFKs and ERK1/2. Biochem Biophys Res Commun 2010; 399:60-5. [PMID: 20638369 DOI: 10.1016/j.bbrc.2010.07.042] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2010] [Accepted: 07/13/2010] [Indexed: 12/22/2022]
Abstract
Betel quid (BQ) is a widely accepted etiological factor for oral squamous cell carcinoma (OSCC) in Southeast Asia, but how BQ chewing leads to oral carcinogenesis remains to be elucidated. We have previously demonstrated that the activation of Src family kinases (SFKs) is critical for BQ-induced oral cancer cell motility. Here we investigate whether this biological effect is mediated by specific membrane receptors in oral cancer cells. We found that BQ-induced activation of extracellular signal-regulated kinase 1/2 (ERK1/2) and cell migration could be inhibited by atropine, suggesting the involvement of the muscarinic receptor family. The enhanced activities of ERK1/2 and cell migration were significantly counteracted by PD102807, the selective antagonist of muscarinic M4 receptor. Moreover, cold BQ extract effectively competed with a known ligand, [(3)H]-N-methyl scopolamine, for binding to muscarinic M4 receptor in vitro, thereby implying that BQ could activate motility-promoting signaling pathways through direct interaction with the receptor. The requirement of muscarinic M4 receptor for BQ-induced oral cancer cell migration was demonstrated by knockdown of the receptor using RNA interference (RNAi). Remarkably, ectopic expression of muscarinic M4 receptor in two oral cancer cell lines, Ca9-22 and SCC-9, further augmented BQ-induced cell migration by 83% and 99%, respectively. Finally, we verified that BQ-induced oral cancer cell migration was mediated through a muscarinic M4 receptor-->SFKs-->ERK1/2 signaling pathway. Thus, our findings have identified a novel signaling cascade mediating BQ-induced oral cancer cell motility, which could be a therapeutic target for BQ-related oral malignancies.
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Affiliation(s)
- Chien-Chih Chiu
- Department of Biotechnology, Kaohsiung Medical University, Taiwan
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Fisher GW, Adler SA, Fuhrman MH, Waggoner AS, Bruchez MP, Jarvik JW. Detection and quantification of beta2AR internalization in living cells using FAP-based biosensor technology. ACTA ACUST UNITED AC 2010; 15:703-9. [PMID: 20488980 DOI: 10.1177/1087057110370892] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Ligand-dependent receptor internalization is a feature of numerous signaling systems. In this article, the authors describe a new kind of live-cell biosensor of receptor internalization that takes advantage of fluorogen-activating protein (FAP) technology. Recombinant genes that express the human beta2 adrenergic receptor (beta2AR) with FAP domains at their extracellular N-termini were transduced into mammalian cells. Exposure of the cells to membrane-impermeant fluorogens led to a strong fluorescent signal from the cell surface. Agonist-dependent translocation of the receptor from the surface to the cell interior was readily observed and quantified by fluorescence microscopy or flow cytometry in a homogeneous format without wash or separation steps. The approach described here is generalizable to other receptors and cell surface proteins and is adaptable to a variety of fluorescence-based high-throughput screening platforms.
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Affiliation(s)
- Gregory W Fisher
- Technology Center for Networks and Pathways, Molecular Biosensor and Imaging Center, Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
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Osmond RIW, Das S, Crouch MF. Development of cell-based assays for cytokine receptor signaling, using an AlphaScreen SureFire assay format. Anal Biochem 2010; 403:94-101. [PMID: 20382104 DOI: 10.1016/j.ab.2010.04.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Revised: 03/21/2010] [Accepted: 04/05/2010] [Indexed: 11/27/2022]
Abstract
The signal transducers and activators of transcription (STAT) proteins are a small family of signaling proteins that are crucial for cytokine and growth factor receptor-mediated signaling in various blood cell types. Despite their central role in immune and hematopoietic cellular regulation, there are relatively few options for monitoring receptor-mediated JAK/STAT signaling events in a cell-based format, without the need for cellular transfections or labor intensive methodology. Indeed, traditional methods such as the Western blot or ELISA remain a standard method for determining the phosphorylation status of endogenous STAT proteins. Here we present data for the rapid detection of endogenous receptor-mediated phosphorylation of multiple STAT proteins using the bead-based AlphaScreen SureFire technology. With three different cell lines (human acute monocytic leukemia THP-1 cells, human erythroleukemic TF-1 cells, and human T lymphocytic Jurkat cells), we have optimized a rapid and homogeneous methodology for monitoring endogenous, receptor-mediated signaling via STAT 1, STAT 3, or STAT 5 phosphorylation, in response to several agonists. These assays, which can be tailored for both standard research applications or high-throughput drug screening applications, afford quantitative data for receptor-mediated signaling mechanisms in an endogenous, cellular environment.
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van der Westhuizen ET, Christopoulos A, Sexton PM, Wade JD, Summers RJ. H2 relaxin is a biased ligand relative to H3 relaxin at the relaxin family peptide receptor 3 (RXFP3). Mol Pharmacol 2010; 77:759-72. [PMID: 20159943 DOI: 10.1124/mol.109.061432] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Relaxin family peptide 3 receptors (RXFP3) are activated by H3-relaxin to inhibit forskolin-stimulated cAMP accumulation and stimulate extracellular signal-regulated kinase (ERK) 1/2 phosphorylation. In this study, we sought to identify novel signaling pathways coupled to RXFP3 and to investigate whether other members of the relaxin peptide family activated these pathways. Two patterns of signaling were observed in RXFP3-expressing Chinese hamster ovary (CHO)-K1 and human embryonic kidney (HEK)-293 cells (CHO-RXFP3 and HEK-RXFP3) and murine septal neuron SN56 cell lines: 1) strong inhibition of forskolin-stimulated cAMP accumulation, ERK1/2 activation and nuclear factor (NF)-kappaB reporter gene activation in cells stimulated with H3 relaxin, with weaker activity observed for H2 relaxin, porcine relaxin, or insulin-like peptide (INSL) 3 and 2) strong stimulation of activator protein (AP)-1 reporter genes by H2 relaxin, with weaker activation observed with H3 or porcine relaxin. Two distinct ligand binding sites were identified on RXFP3-expressing cells using two different radioligands. (125)I-INSL5 A-chain/relaxin-3 B-chain chimera bound with high affinity to the RXFP3-expressing cells with competition by H3 relaxin or a H3 relaxin B-chain dimeric peptide, consistent with previous reports. Binding studies with (125)I-H2 relaxin revealed a distinct binding site with potent competition observed with H2 relaxin, H3 relaxin, or INSL3 and weaker competition with porcine relaxin. Thus H3 relaxin potently activates all signaling pathways coupled to RXFP3, whereas H2 relaxin is an AP-1-biased ligand relative to H3 relaxin.
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Lodge AP, Langmead CJ, Daniel G, Anderson GW, Werry TD. Performance of mouse neural stem cells as a screening reagent: characterization of PAC1 activity in medium-throughput functional assays. ACTA ACUST UNITED AC 2009; 15:159-68. [PMID: 20042531 DOI: 10.1177/1087057109355468] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The self-renewal and phenotypic properties of neural stem cells make them an abundant and more physiologically relevant alternative to recombinant cell lines for drug screens to identify ligands acting at neural targets. Here, the authors use high-throughput phenotypic and signaling assays to test the ability of neural stem cells isolated from postnatal mouse hippocampus (mNSCs) to deliver high-content and physiologically relevant data on native peptide receptor activity. The authors find that mNSCs express PAC1 but not the related VPAC1 and VPAC2 receptors. PAC1 promotes both the proliferation of mNSCs and their differentiation into neuronal-like cells. In addition, the authors show that PAC1 stimulates markedly different extracellular signal-regulated kinase signals in mNSCs than in recombinant CHO-PAC1 cells and is able to couple to Ca(2+) elevation only in CHO-PAC1 cells. These data suggest that G-protein coupling in CHO-PAC1 cells is nonphysiological, which may affect the ligand binding properties of the receptor and thus distort the results of a screen by increasing numbers of false positives/negatives. This work reinforces the emerging pharmacological theory that recombinant cell lines are often inappropriate models of natively expressing primary cells, and the authors conclude that mNSCs are a viable and relevant physiological alternative for use in high-throughput drug screens.
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Affiliation(s)
- Anthony P Lodge
- Neurosciences CED, GlaxoSmithKline Research & Development, Harlow, Essex, UK
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Huwiler KG, Machleidt T, Chase L, Hanson B, Robers MB. Characterization of serotonin 5-hydroxytryptamine-1A receptor activation using a phospho-extracellular-signal regulated kinase 2 sensor. Anal Biochem 2009; 393:95-104. [DOI: 10.1016/j.ab.2009.06.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2009] [Accepted: 06/15/2009] [Indexed: 11/16/2022]
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Heilker R, Wolff M, Tautermann CS, Bieler M. G-protein-coupled receptor-focused drug discovery using a target class platform approach. Drug Discov Today 2009; 14:231-40. [PMID: 19121411 DOI: 10.1016/j.drudis.2008.11.011] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2008] [Revised: 11/05/2008] [Accepted: 11/26/2008] [Indexed: 11/27/2022]
Abstract
In recent years, several large pharmaceutical companies have taken a novel approach to drug discovery biology and chemistry in that they channel their efforts with respect to particular target classes, such as G-protein-coupled receptors (GPCRs), toward dedicated, specialized teams. Benefits of such an organizational structure are the prospects of establishing several target-family-specific experimental techniques and skill sets, thereby enabling a comprehensive functional profiling of drug candidates in different pharmacological respects. In this context, the recently increased number of reports on GPCR ligand-biased signaling has further spurred the efforts in the pharmaceutical industry toward broader biological characterization of the test compounds, for example employing high-content screening to analyze different GPCR ligand-induced signaling pathways. The knowledge of the disease-relevant functional properties of the small molecule GPCR ligands enables target-specific chemical optimization and GPCR-subclass-directed library design. In the case of GPCRs, where little--although at present slowly expanding--structural information on the targets is available, the modeling of GPCR structures crucially depends on biological validation (typically supported by site-directed mutagenesis of the GPCR ligand binding site). In this review, we aim to recapitulate efforts in the pharmaceutical industry to address GPCR-directed drug discovery in a target-class-directed platform approach: establishing GPCR-specific biological assay panels and creating computational chemistry methods for finding and optimizing small molecules modulating the activity of GPCRs.
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Affiliation(s)
- Ralf Heilker
- Department of Lead Discovery, Boehringer Ingelheim Pharma GmbH & Co KG, Biberach, Germany.
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Werry TD, Stewart GD, Crouch MF, Watts A, Sexton PM, Christopoulos A. Pharmacology of 5HT2C receptor-mediated ERK1/2 phosphorylation: Agonist-specific activation pathways and the impact of RNA editing. Biochem Pharmacol 2008; 76:1276-87. [DOI: 10.1016/j.bcp.2008.08.024] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2008] [Revised: 08/25/2008] [Accepted: 08/25/2008] [Indexed: 11/29/2022]
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Ferguson GN, Valant C, Horne J, Figler H, Flynn BL, Linden J, Chalmers DK, Sexton PM, Christopoulos A, Scammells PJ. 2-aminothienopyridazines as novel adenosine A1 receptor allosteric modulators and antagonists. J Med Chem 2008; 51:6165-72. [PMID: 18771255 DOI: 10.1021/jm800557d] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A pharmacophore-based screen identified 32 compounds including ethyl 5-amino-3-(4- tert-butylphenyl)-4-oxo-3,4-dihydrothieno[3,4- d]pyridazine-1-carboxylate ( 8) as a new allosteric modulator of the adenosine A1 receptor (A1AR). On the basis of this lead, various derivatives were prepared and evaluated for activity at the human A 1AR. A number of the test compounds allosterically stabilized agonist-receptor-G protein ternary complexes in dissociation kinetic assays, but were found to be more potent as antagonists in subsequent functional assays of ERK1/2 phosphorylation. Additional experiments on the most potent antagonist, 13b, investigating A1AR-mediated [(35)S]GTPgammaS binding and [(3)H]CCPA equilibrium binding confirmed its antagonistic mode of action and also identified inverse agonism. This study has thus identified a new class of A1AR antagonists that can also recognize the receptor's allosteric site with lower potency.
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Affiliation(s)
- Gemma N Ferguson
- Medicinal Chemistry and Drug Action, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
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Adams DG, Wang Y, Mak PA, Chyba J, Shalizi O, Matzen J, Anderson P, Smith TR, Garcia M, Welch GL, Claret EJ, Fink M, Orth AP, Caldwell JS, Brinker A. Cellular Ser/Thr-kinase assays using generic peptide substrates. CURRENT CHEMICAL GENOMICS 2008; 1:54-64. [PMID: 20161828 PMCID: PMC2774688 DOI: 10.2174/1875397300801010054] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2008] [Revised: 03/31/2008] [Accepted: 04/04/2008] [Indexed: 01/07/2023]
Abstract
High-throughput cellular profiling has successfully stimulated early drug discovery pipelines by facilitating targeted as well as opportunistic lead finding, hit annotation and SAR analysis. While automation-friendly universal assay formats exist to address most established drug target classes like GPCRs, NHRs, ion channels or Tyr-kinases, no such cellular assay technology is currently enabling an equally broad and rapid interrogation of the Ser/Thr-kinase space. Here we present the foundation of an emerging cellular Ser/Thr-kinase platform that involves a) coexpression of targeted kinases with promiscuous peptide substrates and b) quantification of intracellular substrate phosphorylation by homogeneous TR-FRET. Proof-of-concept data is provided for cellular AKT, B-RAF and CamK2δ assays. Importantly, comparable activity profiles were found for well characterized B-Raf inhibitors in TR-FRET assays relying on either promiscuous peptide substrates or a MEK1(WT) protein substrate respectively. Moreover, IC50-values correlated strongly between cellular TR-FRET assays and a gold standard Ba/F3 proliferation assay for B-Raf activity. Finally, we expanded our initial assay panel by screening a kinase-focused cDNA library and identified starting points for >20 cellular Ser/Thr-kinase assays.
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Affiliation(s)
- Deanna G Adams
- Genomics Institute of the Novartis Research Foundation, San Diego, California, USA
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Abstract
G protein-coupled receptors (GPCRs) transmit extracellular signals into the intracellular space, and play key roles in the physiological regulation of virtually every cell and tissue. Characteristic for the GPCR superfamily of cell surface receptors are their seven transmembrane-spanning alpha-helices, an extracellular N terminus and intracellular C-terminal tail. Besides transmission of extracellular signals, their activity is modulated by cellular signals in an auto- or transregulatory fashion. The molecular complexity of GPCRs and their regulated signaling networks triggered the interest in academic research groups to explore them further, and their drugability and role in pathophysiology triggers pharmaceutical research towards small molecular weight ligands and therapeutic antibodies. About 30% of marketed drugs target GPCRs, which underlines the importance of this target class. This review describes current and emerging cellular assays for the ligand discovery of GPCRs.
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Affiliation(s)
- Sandra Siehler
- Novartis Institutes for BioMedical Research Basel, Center for Proteomic Chemistry, Novartis Pharma AG, 4002 Basel, Switzerland.
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Eglen RM, Reisine T, Roby P, Rouleau N, Illy C, Bossé R, Bielefeld M. The use of AlphaScreen technology in HTS: current status. CURRENT CHEMICAL GENOMICS 2008; 1:2-10. [PMID: 20161822 PMCID: PMC2775125 DOI: 10.2174/1875397300801010002] [Citation(s) in RCA: 170] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2007] [Revised: 01/13/2008] [Accepted: 01/19/2008] [Indexed: 11/22/2022]
Abstract
AlphaScreen (Amplified Luminescent Proximity Homogeneous Assay Screen) is versatile assay technology developed to measuring analytes using a homogenous protocol. This technology is an example of a bead-based proximity assay and was developed from a diagnostic assay technology known as LOCI (Luminescent Oxygen Channeling Assay). Here, singlet oxygen molecules, generated by high energy irradiation of Donor beads, travel over a constrained distance (approx. 200 nm) to Acceptor beads. This results in excitation of a cascading series of chemical reactions, ultimately causing generation of a chemiluminescent signal.In the past decade, a wide variety of applications has been reported, ranging from detection of analytes involved in cell signaling, including protein:protein, protein:peptide, protein:small molecule or peptide:peptide interactions. Numerous homogeneous HTS-optimized assays have been reported using the approach, including generation of second messengers (such as accumulation of cyclic AMP, cyclic GMP, inositol [1, 4, 5] trisphosphate or phosphorylated ERK) from liganded GPCRs or tyrosine kinase receptors, post-translational modification of proteins (such as proteolytic cleavage, phosphorylation, ubiquination and sumoylation) as well as protein-protein and protein-nucleic acid interactions.Recently, the basic AlphaScreen technology was extended in that the chemistry of the Acceptor bead was modified such that emitted light is more intense and spectrally defined, thereby markedly reducing interference from biological fluid matrices (such as trace hemolysis in serum and plasma). In this format, referred to as AlphaLISA, it provides an alternative technology to classical ELISA assays and is suitable for high throughput automated fluid dispensing and detection systems.Collectively, AlphaScreen and AlphaLISA technologies provide a facile assay platform with which one can quantitate complex cellular processes using simple no-wash microtiter plate based assays. They provide the means by which large compound libraries can be screened in a high throughput fashion at a diverse range of therapeutically important targets, often not readily undertaken using other homogeneous assay technologies. This review assesses the current status of the technology in drug discovery, in general, and high throughput screening (HTS), in particular.
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Affiliation(s)
- Richard M Eglen
- President, Molecular Medicine, PerkinElmer Life and Analytical Sciences, 940 Winter St., Waltham, MA 02451-1457, USA.
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Binder C, Lafayette A, Archibeque I, Sun Y, Plewa C, Sinclair A, Emkey R. Optimization and Utilization of the SureFire Phospho-STAT5 Assay for a Cell-Based Screening Campaign. Assay Drug Dev Technol 2008; 6:27-37. [DOI: 10.1089/adt.2007.111] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
| | | | | | - Yu Sun
- Amgen Inc., Thousand Oaks, California
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