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Dupont AC, Arlicot N, Vercouillie J, Serrière S, Maia S, Bonnet-Brilhault F, Santiago-Ribeiro MJ. Metabotropic Glutamate Receptor Subtype 5 Positron-Emission-Tomography Radioligands as a Tool for Central Nervous System Drug Development: Between Progress and Setbacks. Pharmaceuticals (Basel) 2023; 16:1127. [PMID: 37631042 PMCID: PMC10458693 DOI: 10.3390/ph16081127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 08/03/2023] [Accepted: 08/09/2023] [Indexed: 08/27/2023] Open
Abstract
The metabotropic glutamate receptor subtype 5 (mGluR5) is a class C G-protein-coupled receptor (GPCR) that has been implicated in various neuronal processes and, consequently, in several neuropsychiatric or neurodevelopmental disorders. Over the past few decades, mGluR5 has become a major focus for pharmaceutical companies, as an attractive target for drug development, particularly through the therapeutic potential of its modulators. In particular, allosteric binding sites have been targeted for better specificity and efficacy. In this context, Positron Emission Tomography (PET) appears as a useful tool for making decisions along a drug candidate's development process, saving time and money. Thus, PET provides quantitative information about a potential drug candidate and its target at the molecular level. However, in this area, particular attention has to be given to the interpretation of the PET signal and its conclusions. Indeed, the complex pharmacology of both mGluR5 and radioligands, allosterism, the influence of endogenous glutamate and the choice of pharmacokinetic model are all factors that may influence the PET signal. This review focuses on mGluR5 PET radioligands used at several stages of central nervous system drug development, highlighting advances and setbacks related to the complex pharmacology of these radiotracers.
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Affiliation(s)
- Anne-Claire Dupont
- Radiopharmacie, CHRU de Tours, 37000 Tours, France
- UMR 1253, iBrain, Tours University, INSERM, 37000 Tours, France
| | - Nicolas Arlicot
- Radiopharmacie, CHRU de Tours, 37000 Tours, France
- UMR 1253, iBrain, Tours University, INSERM, 37000 Tours, France
- CIC 1415, Tours University, INSERM, 37000 Tours, France
| | | | - Sophie Serrière
- UMR 1253, iBrain, Tours University, INSERM, 37000 Tours, France
| | - Serge Maia
- Radiopharmacie, CHRU de Tours, 37000 Tours, France
- UMR 1253, iBrain, Tours University, INSERM, 37000 Tours, France
| | - Frédérique Bonnet-Brilhault
- UMR 1253, iBrain, Tours University, INSERM, 37000 Tours, France
- Excellence Center for Autism and Neurodevelopmental Disorders, CHRU de Tours, 37000 Tours, France
| | - Maria-Joao Santiago-Ribeiro
- UMR 1253, iBrain, Tours University, INSERM, 37000 Tours, France
- Nuclear Medicine Department, CHRU de Tours, 37000 Tours, France
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2
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Ngomba RT, Lüttjohann A, Dexter A, Ray S, van Luijtelaar G. The Metabotropic Glutamate 5 Receptor in Sleep and Wakefulness: Focus on the Cortico-Thalamo-Cortical Oscillations. Cells 2023; 12:1761. [PMID: 37443795 PMCID: PMC10341329 DOI: 10.3390/cells12131761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 06/17/2023] [Accepted: 06/27/2023] [Indexed: 07/15/2023] Open
Abstract
Sleep is an essential innate but complex behaviour which is ubiquitous in the animal kingdom. Our knowledge of the distinct neural circuit mechanisms that regulate sleep and wake states in the brain are, however, still limited. It is therefore important to understand how these circuits operate during health and disease. This review will highlight the function of mGlu5 receptors within the thalamocortical circuitry in physiological and pathological sleep states. We will also evaluate the potential of targeting mGlu5 receptors as a therapeutic strategy for sleep disorders that often co-occur with epileptic seizures.
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Affiliation(s)
| | - Annika Lüttjohann
- Institute of Physiology I, University of Münster, 48149 Münster, Germany
| | - Aaron Dexter
- School of Pharmacy, University of Lincoln, Lincoln LN6 7DL, UK
| | - Swagat Ray
- Department of Life Sciences, School of Life and Environmental Sciences, University of Lincoln, Lincoln LN6 7DL, UK
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3
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Brown J, Grayson B, Neill JC, Harte M, Wall MJ, Ngomba RT. Oscillatory Deficits in the Sub-Chronic PCP Rat Model for Schizophrenia Are Reversed by mGlu5 Receptor-Positive Allosteric Modulators VU0409551 and VU0360172. Cells 2023; 12:cells12060919. [PMID: 36980260 PMCID: PMC10047164 DOI: 10.3390/cells12060919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 03/13/2023] [Accepted: 03/15/2023] [Indexed: 03/19/2023] Open
Abstract
The cognitive deficits of schizophrenia are linked to imbalanced excitatory and inhibitory signalling in the prefrontal cortex (PFC), disrupting gamma oscillations. We previously demonstrated that two mGlu5 receptor-positive allosteric modulators (PAMs), VU0409551 and VU0360172, restore cognitive deficits in the sub-chronic PCP (scPCP) rodent model for schizophrenia via distinct changes in PFC intracellular signalling molecules. Here, we have assessed ex vivo gamma oscillatory activity in PFC slices from scPCP rats and investigated the effects of VU0409551 and VU0360172 upon oscillatory power. mGlu5 receptor, protein kinase C (PKC), and phospholipase C (PLC) inhibition were also used to examine ‘modulation bias’ in PAM activity. The amplitude and area power of gamma oscillations were significantly diminished in the scPCP model. Slice incubation with either VU0409551 or VU0360172 rescued scPCP-induced oscillatory deficits in a concentration-dependent manner. MTEP blocked the PAM-induced restoration of oscillatory power, confirming the requirement of mGlu5 receptor modulation. Whilst PLC inhibition prevented the power increase mediated by both PAMs, PKC inhibition diminished the effects of VU0360172 but not VU0409551. This aligns with previous reports that VU0409551 exhibits preferential activation of the phosphatidylinositol-3-kinase (PI3K) signalling pathway over the PKC cascade. Restoration of the excitatory/inhibitory signalling balance and gamma oscillations may therefore underlie the mGluR5 PAM-mediated correction of scPCP-induced cognitive deficits.
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Affiliation(s)
- Jessica Brown
- Division of Pharmacy & Optometry, University of Manchester, Manchester M13 9PT, UK
| | - Ben Grayson
- Division of Pharmacy & Optometry, University of Manchester, Manchester M13 9PT, UK
| | - Joanna C. Neill
- Division of Pharmacy & Optometry, University of Manchester, Manchester M13 9PT, UK
| | - Michael Harte
- Division of Pharmacy & Optometry, University of Manchester, Manchester M13 9PT, UK
- Correspondence: (M.H.); (M.J.W.); (R.T.N.); Tel.: +44-(0)161-2752328 (M.H.); +44-(0)247-6573772 (M.J.W.); +44-(0)152-2837392 (R.T.N.)
| | - Mark J. Wall
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
- Correspondence: (M.H.); (M.J.W.); (R.T.N.); Tel.: +44-(0)161-2752328 (M.H.); +44-(0)247-6573772 (M.J.W.); +44-(0)152-2837392 (R.T.N.)
| | - Richard T. Ngomba
- School of Pharmacy, University of Lincoln, Lincoln LN6 7DL, UK
- Correspondence: (M.H.); (M.J.W.); (R.T.N.); Tel.: +44-(0)161-2752328 (M.H.); +44-(0)247-6573772 (M.J.W.); +44-(0)152-2837392 (R.T.N.)
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4
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Holter KM, Pierce BE, Gould RW. Metabotropic glutamate receptor function and regulation of sleep-wake cycles. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2023; 168:93-175. [PMID: 36868636 DOI: 10.1016/bs.irn.2022.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Metabotropic glutamate (mGlu) receptors are the most abundant family of G-protein coupled receptors and are widely expressed throughout the central nervous system (CNS). Alterations in glutamate homeostasis, including dysregulations in mGlu receptor function, have been indicated as key contributors to multiple CNS disorders. Fluctuations in mGlu receptor expression and function also occur across diurnal sleep-wake cycles. Sleep disturbances including insomnia are frequently comorbid with neuropsychiatric, neurodevelopmental, and neurodegenerative conditions. These often precede behavioral symptoms and/or correlate with symptom severity and relapse. Chronic sleep disturbances may also be a consequence of primary symptom progression and can exacerbate neurodegeneration in disorders including Alzheimer's disease (AD). Thus, there is a bidirectional relationship between sleep disturbances and CNS disorders; disrupted sleep may serve as both a cause and a consequence of the disorder. Importantly, comorbid sleep disturbances are rarely a direct target of primary pharmacological treatments for neuropsychiatric disorders even though improving sleep can positively impact other symptom clusters. This chapter details known roles of mGlu receptor subtypes in both sleep-wake regulation and CNS disorders focusing on schizophrenia, major depressive disorder, post-traumatic stress disorder, AD, and substance use disorder (cocaine and opioid). In this chapter, preclinical electrophysiological, genetic, and pharmacological studies are described, and, when possible, human genetic, imaging, and post-mortem studies are also discussed. In addition to reviewing the important relationships between sleep, mGlu receptors, and CNS disorders, this chapter highlights the development of selective mGlu receptor ligands that hold promise for improving both primary symptoms and sleep disturbances.
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Affiliation(s)
- Kimberly M Holter
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - Bethany E Pierce
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - Robert W Gould
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC, United States.
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5
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van Senten JR, Møller TC, Von Moo E, Seiersen SD, Bräuner-Osborne H. Use of CRISPR/Cas9-edited HEK293 cells reveals that both conventional and novel protein kinase C isozymes are involved in mGlu 5a receptor internalization. J Biol Chem 2022; 298:102466. [PMID: 36087841 PMCID: PMC9530845 DOI: 10.1016/j.jbc.2022.102466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 08/17/2022] [Accepted: 08/19/2022] [Indexed: 11/15/2022] Open
Abstract
The internalization of G protein-coupled receptors (GPCRs) can be regulated by protein kinase C (PKC). However, most tools available to study the contribution of PKC isozymes have considerable limitations, including a lack of selectivity. In this study, we generated and characterized human embryonic kidney 293A (HEK293A) cell lines devoid of conventional or novel PKC isozymes (ΔcPKC and ΔnPKC) and employ these to investigate the contribution of PKC isozymes in the internalization of the metabotropic glutamate receptor 5 (mGlu5). Direct activation of PKC and mutation of rat mGlu5a Ser901, a PKC-dependent phosphorylation site in the receptor C-tail, both showed that PKC isozymes facilitate approximately 40% of the receptor internalization. Nonetheless, we determined that mGlu5a internalization was not altered upon the loss of cPKCs or nPKCs. This indicates that isozymes from both classes are involved, compensate for the absence of the other class, and thus fulfill dispensable functions. Additionally, using the Gαq/11 inhibitor YM-254890, GPCR kinase 2 and 3 (GRK2 and GRK3) knock-out cells and a receptor containing a mutated putative adaptor protein complex 2 (AP-2) interaction motif, we demonstrate that internalization of rat mGlu5a is mediated by Gαq/11 proteins (77% of the response), GRK2 (27%) and AP-2 (29%), but not GRK3. Our PKC knock-out cell lines expand the repertoire of knock-out HEK293A cell lines available to research GPCR pharmacology. Moreover, since pharmacological tools to study PKC isozymes generally lack specificity and/or potency, we present the PKC knock-out cell lines as more specific research tools to investigate PKC-mediated aspects of cell biology.
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Affiliation(s)
- Jeffrey R van Senten
- Department of Drug Design and Pharmacology, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Thor C Møller
- Department of Drug Design and Pharmacology, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Ee Von Moo
- Department of Drug Design and Pharmacology, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Sofie D Seiersen
- Department of Drug Design and Pharmacology, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Hans Bräuner-Osborne
- Department of Drug Design and Pharmacology, University of Copenhagen, 2100 Copenhagen, Denmark.
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Caffino L, Mottarlini F, Targa G, Verheij MMM, Fumagalli F, Homberg JR. Responsivity of serotonin transporter knockout rats to short and long access to cocaine: modulation of the glutamate signaling in the nucleus accumbens shell. Br J Pharmacol 2022; 179:3727-3739. [PMID: 35174489 PMCID: PMC9310702 DOI: 10.1111/bph.15823] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 02/01/2022] [Accepted: 02/04/2022] [Indexed: 11/28/2022] Open
Abstract
Background and Purpose It has been well established that glutamate in the nucleus accumbens (NAc) plays a critical role in the motivation to take drugs of abuse. We have previously demonstrated that rats with ablation of the serotonin transporter (SERT−/− rats) show increased cocaine intake reminiscent of compulsivity. Experimental Approach By comparing SERT−/− to SERT+/+ rats, we investigated whether SERT deletion influences glutamate homeostasis under control conditions as well as after short access (ShA: 1 h per session) or long access (LgA: 6 h per session) to cocaine self‐administration. Rats were killed at 24 h after the last self‐administration session for ex vivo molecular analyses of the main determinants of the glutamate system, including transporters (vesicular and glial), receptors (main post‐synaptic subunits of NMDA and AMPA receptors together with the metabotropic subunit mGLUR5), and scaffolding proteins (SAP102, SAP97, and GRIP) in the NAc shell (sNAc) Key Results In cocaine‐naive animals, SERT deletion was associated with changes indicative for a reduction in glutamate signalling. ShA and LgA exposure led to a further dysregulation of the glutamatergic synapse. Conclusion SERT deletion may render the glutamatergic synapses of the NAc shell more responsive to both ShA and LgA intake of cocaine.
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Affiliation(s)
- Lucia Caffino
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Italy
| | - Francesca Mottarlini
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Italy
| | - Giorgia Targa
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Italy
| | - Michel M M Verheij
- Department of Cognitive Neuroscience, division of Molecular Neurogenetics, Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen Medical Centre, the Netherlands
| | - Fabio Fumagalli
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Italy
| | - Judith R Homberg
- Department of Cognitive Neuroscience, division of Molecular Neurogenetics, Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen Medical Centre, the Netherlands
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7
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Holter KM, Lekander AD, LaValley CM, Bedingham EG, Pierce BE, Sands LP, Lindsley CW, Jones CK, Gould RW. Partial mGlu 5 Negative Allosteric Modulator M-5MPEP Demonstrates Antidepressant-Like Effects on Sleep Without Affecting Cognition or Quantitative EEG. Front Neurosci 2021; 15:700822. [PMID: 34276300 PMCID: PMC8283128 DOI: 10.3389/fnins.2021.700822] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 06/03/2021] [Indexed: 01/28/2023] Open
Abstract
Selective negative allosteric modulators (NAMs) targeting the metabotropic glutamate receptor subtype 5 (mGlu5) demonstrate anxiolytic-like and antidepressant-like effects yet concern regarding adverse effect liability remains. Functional coupling of mGlu5 with ionotropic N-methyl-D-aspartate receptors (NMDARs) represents a potential mechanism through which full inhibition leads to adverse effects, as NMDAR inhibition can induce cognitive impairments and psychotomimetic-like effects. Recent development of "partial" mGlu5 NAMs, characterized by submaximal but saturable levels of blockade, may represent a novel development approach to broaden the therapeutic index of mGlu5 NAMs. This study compared the partial mGlu5 NAM, M-5MPEP, with the full mGlu5 NAM, VU0424238 on sleep, cognition, and brain function alone and in combination with a subthreshold dose of the NMDAR antagonist, MK-801, using a paired-associates learning (PAL) cognition task and electroencephalography (EEG) in rats. M-5MPEP and VU0424238 decreased rapid eye movement (REM) sleep and increased REM sleep latency, both putative biomarkers of antidepressant-like activity. Neither compound alone affected accuracy, but 30 mg/kg VU0424238 combined with MK-801 decreased accuracy on the PAL task. Using quantitative EEG, VU0424238, but not M-5MPEP, prolonged arousal-related elevations in high gamma power, and, in combination, VU0424238 potentiated effects of MK-801 on high gamma power. Together, these studies further support a functional interaction between mGlu5 and NMDARs that may correspond with cognitive impairments. Present data support further development of partial mGlu5 NAMs given their potentially broader therapeutic index than full mGlu5 NAMs and use of EEG as a translational biomarker to titrate doses aligning with therapeutic versus adverse effects.
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Affiliation(s)
- Kimberly M. Holter
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Alex D. Lekander
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Christina M. LaValley
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | | | - Bethany E. Pierce
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - L. Paul Sands
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Craig W. Lindsley
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, United States
- Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, United States
- Department of Chemistry, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Carrie K. Jones
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, United States
- Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, United States
| | - Robert W. Gould
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, United States
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8
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Gonzalez-Lozano MA, Wortel J, van der Loo RJ, van Weering JRT, Smit AB, Li KW. Reduced mGluR5 Activity Modulates Mitochondrial Function. Cells 2021; 10:cells10061375. [PMID: 34199502 PMCID: PMC8228325 DOI: 10.3390/cells10061375] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 05/23/2021] [Accepted: 05/31/2021] [Indexed: 11/30/2022] Open
Abstract
The metabotropic glutamate receptor 5 (mGluR5) is an essential modulator of synaptic plasticity, learning and memory; whereas in pathological conditions, it is an acknowledged therapeutic target that has been implicated in multiple brain disorders. Despite robust pre-clinical data, mGluR5 antagonists failed in several clinical trials, highlighting the need for a better understanding of the mechanisms underlying mGluR5 function. In this study, we dissected the molecular synaptic modulation mediated by mGluR5 using genetic and pharmacological mouse models to chronically and acutely reduce mGluR5 activity. We found that next to dysregulation of synaptic proteins, the major regulation in protein expression in both models concerned specific processes in mitochondria, such as oxidative phosphorylation. Second, we observed morphological alterations in shape and area of specifically postsynaptic mitochondria in mGluR5 KO synapses using electron microscopy. Third, computational and biochemical assays suggested an increase of mitochondrial function in neurons, with increased level of NADP/H and oxidative damage in mGluR5 KO. Altogether, our observations provide diverse lines of evidence of the modulation of synaptic mitochondrial function by mGluR5. This connection suggests a role for mGluR5 as a mediator between synaptic activity and mitochondrial function, a finding which might be relevant for the improvement of the clinical potential of mGluR5.
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Affiliation(s)
- Miguel A. Gonzalez-Lozano
- Center for Neurogenomics and Cognitive Research, Department of Molecular and Cellular Neurobiology, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, 1081 Amsterdam, The Netherlands; (R.J.v.d.L.); (A.B.S.)
- Correspondence: (M.A.G.-L.); (K.W.L.)
| | - Joke Wortel
- Center for Neurogenomics and Cognitive Research, Department of Functional Genomics, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, 1081 Amsterdam, The Netherlands; (J.W.); (J.R.T.v.W.)
| | - Rolinka J. van der Loo
- Center for Neurogenomics and Cognitive Research, Department of Molecular and Cellular Neurobiology, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, 1081 Amsterdam, The Netherlands; (R.J.v.d.L.); (A.B.S.)
| | - Jan R. T. van Weering
- Center for Neurogenomics and Cognitive Research, Department of Functional Genomics, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, 1081 Amsterdam, The Netherlands; (J.W.); (J.R.T.v.W.)
- Center for Neurogenomics and Cognitive Research, Department of Clinical Genetics, Amsterdam Neuroscience, Amsterdam UMC location VUmc, 1081 Amsterdam, The Netherlands
| | - August B. Smit
- Center for Neurogenomics and Cognitive Research, Department of Molecular and Cellular Neurobiology, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, 1081 Amsterdam, The Netherlands; (R.J.v.d.L.); (A.B.S.)
| | - Ka Wan Li
- Center for Neurogenomics and Cognitive Research, Department of Molecular and Cellular Neurobiology, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, 1081 Amsterdam, The Netherlands; (R.J.v.d.L.); (A.B.S.)
- Correspondence: (M.A.G.-L.); (K.W.L.)
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Abstract
Methamphetamine abuse leads to devastating consequences, including addiction, crime, and death. Despite decades of research, no medication has been approved by the U.S. Food and Drug Administration for the treatment of Methamphetamine Use Disorder. Thus, there is a need for new therapeutic approaches. Animal studies demonstrate that methamphetamine exposure dysregulates forebrain function involving the Group-I metabotropic glutamate receptor subtype 5 (mGlu5), which is predominantly localized to postsynaptic sites. Allosteric modulators of mGlu5 offer a unique opportunity to modulate glutamatergic neurotransmission selectively, thereby potentially ameliorating methamphetamine-induced disruptions. Negative allosteric modulators of mGlu5 attenuate the effects of methamphetamine, including rewarding/reinforcing properties of the drug across animal models, and have shown promising effects in clinical trials for Anxiety Disorder and Major Depressive Disorder. Preclinical studies have also sparked great interest in mGlu5 positive allosteric modulators, which exhibit antipsychotic and anxiolytic properties, and facilitate extinction learning when access to methamphetamine is removed, possibly via the amelioration of methamphetamine-induced cognitive deficits. Clinical research is now needed to elucidate the mechanisms underlying the mGlu5 receptor-related effects of methamphetamine and the contributions of these effects to addictive behaviors. The growing array of mGlu5 allosteric modulators provides excellent tools for this purpose and may offer the prospect of developing tailored and effective medications for Methamphetamine Use Disorder.
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10
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Wang Y, Gu L, Yang HM, Zhang H. Cystic fibrosis transmembrane conductance regulator-associated ligand protects dopaminergic neurons by differentially regulating metabotropic glutamate receptor 5 in the progression of neurotoxin 6-hydroxydopamine-induced Parkinson's disease model. Neurotoxicology 2021; 84:14-29. [PMID: 33571554 DOI: 10.1016/j.neuro.2021.02.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Revised: 12/21/2020] [Accepted: 02/04/2021] [Indexed: 10/22/2022]
Abstract
Due to limitations in early diagnosis and treatments of Parkinson's disease (PD), it is necessary to explore the neuropathological changes that occur early in PD progression and to design neuroprotective therapies to prevent or delay the ongoing degeneration process. Metabotropic glutamate receptor 5 (mGlu5) has shown both diagnostic and therapeutic potential in preclinical studies on PD. Clinical trials using mGlu5 negative allosteric modulators to treat PD have, however, raised limitations about the neuroprotective role of mGlu5. It is likely that mGlu5 has different regulatory roles in different stages of PD. Here, we investigated a protective role of cystic fibrosis transmembrane conductance regulator-associated ligand (CAL) in the progression of PD by differential regulation of mGlu5 expression and activity to protect against 6-hydroxydopamine (6-OHDA)-induced neurotoxicity. Following treatment with 6-OHDA, mGlu5 and CAL expressions were elevated in the early stage and reduced in the late stage, both in vitro and in vivo. Activation of mGlu5 in the early stage by (RS)-2-chloro-5-hydroxyphenylglycine, or blocking mGlu5 in the late stage by 2-methyl-6-(phenylethynyl) pyridine, increased cell survival and inhibited apoptosis, but these effects were significantly weakened by knockdown of CAL. CAL alleviated 6-OHDA-induced neurotoxicity by regulating mGlu5-mediated signaling pathways, thereby maintaining the physiological function of mGlu5 in different disease stages. In PD rat model, CAL deficiency aggravated 6-OHDA toxicity on dopaminergic neurons and increased motor dysfunction because of lack of regulation of mGlu5 activity. These data reveal a potential mechanism by which CAL specifically regulates the opposite activity of mGlu5 in progression of PD to protect against neurotoxicity, suggesting that CAL is a favorable endogenous target for the treatment of PD.
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Affiliation(s)
- Yuan Wang
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Key Laboratory of Neural Regeneration and Repair, Beijing Institute for Brain Disorders, Capital Medical University, No. 10 Xitoutiao, You An Men, Beijing, 100069, China
| | - Li Gu
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Key Laboratory of Neural Regeneration and Repair, Beijing Institute for Brain Disorders, Capital Medical University, No. 10 Xitoutiao, You An Men, Beijing, 100069, China
| | - Hui Min Yang
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Key Laboratory of Neural Regeneration and Repair, Beijing Institute for Brain Disorders, Capital Medical University, No. 10 Xitoutiao, You An Men, Beijing, 100069, China
| | - Hong Zhang
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Key Laboratory of Neural Regeneration and Repair, Beijing Institute for Brain Disorders, Capital Medical University, No. 10 Xitoutiao, You An Men, Beijing, 100069, China.
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11
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Fasciani I, Petragnano F, Aloisi G, Marampon F, Carli M, Scarselli M, Maggio R, Rossi M. Allosteric Modulators of G Protein-Coupled Dopamine and Serotonin Receptors: A New Class of Atypical Antipsychotics. Pharmaceuticals (Basel) 2020; 13:ph13110388. [PMID: 33202534 PMCID: PMC7696972 DOI: 10.3390/ph13110388] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 11/06/2020] [Accepted: 11/11/2020] [Indexed: 12/23/2022] Open
Abstract
Schizophrenia was first described by Emil Krapelin in the 19th century as one of the major mental illnesses causing disability worldwide. Since the introduction of chlorpromazine in 1952, strategies aimed at modifying the activity of dopamine receptors have played a major role for the treatment of schizophrenia. The introduction of atypical antipsychotics with clozapine broadened the range of potential targets for the treatment of this psychiatric disease, as they also modify the activity of the serotoninergic receptors. Interestingly, all marketed drugs for schizophrenia bind to the orthosteric binding pocket of the receptor as competitive antagonists or partial agonists. In recent years, a strong effort to develop allosteric modulators as potential therapeutic agents for schizophrenia was made, mainly for the several advantages in their use. In particular, the allosteric binding sites are topographically distinct from the orthosteric pockets, and thus drugs targeting these sites have a higher degree of receptor subunit specificity. Moreover, “pure” allosteric modulators maintain the temporal and spatial fidelity of native orthosteric ligand. Furthermore, allosteric modulators have a “ceiling effect”, and their modulatory effect is saturated above certain concentrations. In this review, we summarize the progresses made in the identification of allosteric drugs for dopamine and serotonin receptors, which could lead to a new generation of atypical antipsychotics with a better profile, especially in terms of reduced side effects.
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Affiliation(s)
- Irene Fasciani
- Department of Biotechnological and Applied Clinical Sciences, University of l’Aquila, 67100 L’Aquila, Italy; (I.F.); (F.P.); (G.A.)
| | - Francesco Petragnano
- Department of Biotechnological and Applied Clinical Sciences, University of l’Aquila, 67100 L’Aquila, Italy; (I.F.); (F.P.); (G.A.)
| | - Gabriella Aloisi
- Department of Biotechnological and Applied Clinical Sciences, University of l’Aquila, 67100 L’Aquila, Italy; (I.F.); (F.P.); (G.A.)
| | - Francesco Marampon
- Department of Radiotherapy, “Sapienza” University of Rome, Policlinico Umberto I, 00161 Rome, Italy;
| | - Marco Carli
- Department of Translational Research and New Technology in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy; (M.C.); (M.S.)
| | - Marco Scarselli
- Department of Translational Research and New Technology in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy; (M.C.); (M.S.)
| | - Roberto Maggio
- Department of Biotechnological and Applied Clinical Sciences, University of l’Aquila, 67100 L’Aquila, Italy; (I.F.); (F.P.); (G.A.)
- Correspondence:
| | - Mario Rossi
- Institute of Molecular Cell and Systems Biology, University of Glasgow, Glasgow G12 8QQ, UK;
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12
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Evenseth LSM, Gabrielsen M, Sylte I. The GABA B Receptor-Structure, Ligand Binding and Drug Development. Molecules 2020; 25:molecules25133093. [PMID: 32646032 PMCID: PMC7411975 DOI: 10.3390/molecules25133093] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 07/02/2020] [Accepted: 07/06/2020] [Indexed: 11/17/2022] Open
Abstract
The γ-aminobutyric acid (GABA) type B receptor (GABAB-R) belongs to class C of the G-protein coupled receptors (GPCRs). Together with the GABAA receptor, the receptor mediates the neurotransmission of GABA, the main inhibitory neurotransmitter in the central nervous system (CNS). In recent decades, the receptor has been extensively studied with the intention being to understand pathophysiological roles, structural mechanisms and develop drugs. The dysfunction of the receptor is linked to a broad variety of disorders, including anxiety, depression, alcohol addiction, memory and cancer. Despite extensive efforts, few compounds are known to target the receptor, and only the agonist baclofen is approved for clinical use. The receptor is a mandatory heterodimer of the GABAB1 and GABAB2 subunits, and each subunit is composed of an extracellular Venus Flytrap domain (VFT) and a transmembrane domain of seven α-helices (7TM domain). In this review, we briefly present the existing knowledge about the receptor structure, activation and compounds targeting the receptor, emphasizing the role of the receptor in previous and future drug design and discovery efforts.
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Affiliation(s)
- Linn Samira Mari Evenseth
- Molecular Pharmacology and Toxicology, Department of Medical Biology, Faculty of Health Sciences, UiT The Arctic University of Norway, NO-9037 Tromsø, Norway
| | - Mari Gabrielsen
- Molecular Pharmacology and Toxicology, Department of Medical Biology, Faculty of Health Sciences, UiT The Arctic University of Norway, NO-9037 Tromsø, Norway
| | - Ingebrigt Sylte
- Molecular Pharmacology and Toxicology, Department of Medical Biology, Faculty of Health Sciences, UiT The Arctic University of Norway, NO-9037 Tromsø, Norway
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13
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Sengmany K, Hellyer SD, Christopoulos A, Lapinsky DJ, Leach K, Gregory KJ. Differential contribution of metabotropic glutamate receptor 5 common allosteric binding site residues to biased allosteric agonism. Biochem Pharmacol 2020; 177:114011. [DOI: 10.1016/j.bcp.2020.114011] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 04/29/2020] [Indexed: 01/06/2023]
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14
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Probe dependence and biased potentiation of metabotropic glutamate receptor 5 is mediated by differential ligand interactions in the common allosteric binding site. Biochem Pharmacol 2020; 177:114013. [DOI: 10.1016/j.bcp.2020.114013] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 04/30/2020] [Indexed: 01/04/2023]
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15
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Jong YJI, Harmon SK, O’Malley KL. Location and Cell-Type-Specific Bias of Metabotropic Glutamate Receptor, mGlu 5, Negative Allosteric Modulators. ACS Chem Neurosci 2019; 10:4558-4570. [PMID: 31609579 DOI: 10.1021/acschemneuro.9b00415] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Emerging data indicate that G-protein coupled receptor (GPCR) signaling is determined by not only the agonist and a given receptor but also a variety of cell-type-specific factors that can influence a receptor's response. For example, the metabotropic glutamate receptor, mGlu5, which is implicated in a number of neuropsychiatric disorders such as depression, anxiety, and autism, also signals from inside the cell which leads to sustained Ca2+ mobilization versus rapid transient responses. Because mGlu5 is an important drug target, many negative allosteric modulators (NAMs) have been generated to modulate its activity. Here we show that NAMs such as AFQ056, AZD2066, and RG7090 elicit very different end points when tested in postnatal neuronal cultures expressing endogenous mGlu5 receptors. For example, AFQ056 fails to block intracellular mGlu5-mediated Ca2+ increases whereas RG7090 is very effective. These differences are not due to differential receptor levels, since about the same number of mGlu5 receptors are present on neurons from the cortex, hippocampus, and striatum based on pharmacological, biochemical, and molecular data. Moreover, biotinylation studies reveal that more than 90% of the receptor is intracellular in these neurons. Taken together, these data indicate that the tested NAMs exhibit both location-dependent and cell type specific bias for mGlu5-mediated Ca2+ mobilization which may affect clinical outcomes.
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Affiliation(s)
- Yuh-Jiin Ivy Jong
- Department of Neuroscience, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Steven K. Harmon
- Department of Neuroscience, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
| | - Karen L. O’Malley
- Department of Neuroscience, Washington University School of Medicine, Saint Louis, Missouri 63110, United States
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16
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Gregory KJ, Giraldo J, Diao J, Christopoulos A, Leach K. Evaluation of Operational Models of Agonism and Allosterism at Receptors with Multiple Orthosteric Binding Sites. Mol Pharmacol 2019; 97:35-45. [DOI: 10.1124/mol.119.118091] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 11/04/2019] [Indexed: 12/15/2022] Open
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17
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Hellyer SD, Albold S, Sengmany K, Singh J, Leach K, Gregory KJ. Metabotropic glutamate receptor 5 (mGlu 5 )-positive allosteric modulators differentially induce or potentiate desensitization of mGlu 5 signaling in recombinant cells and neurons. J Neurochem 2019; 151:301-315. [PMID: 31376155 DOI: 10.1111/jnc.14844] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 07/17/2019] [Accepted: 07/31/2019] [Indexed: 12/14/2022]
Abstract
Allosteric modulators of metabotropic glutamate receptor 5 (mGlu5 ) are a promising therapeutic strategy for a number of neurological disorders. Multiple mGlu5 -positive allosteric modulator (PAM) chemotypes have been discovered that act as either pure PAMs or as PAM-agonists in recombinant and native cells. While these compounds have been tested in paradigms of receptor activation, their effects on receptor regulatory processes are largely unknown. In this study, acute desensitization of mGlu5 mediated intracellular calcium mobilization by structurally diverse mGlu5 orthosteric and allosteric ligands was assessed in human embryonic kidney 293 cells and primary murine neuronal cultures from both striatum and cortex. We aimed to determine the intrinsic efficacy and modulatory capacity of diverse mGlu5 PAMs [(R)-5-((3-fluorophenyl)ethynyl)-N-(3-hydroxy-3-methylbutan-2-yl)picolinamide (VU0424465), N-cyclobutyl-6-((3-fluorophenyl)ethynyl)picolinamide (VU0360172), 1-(4-(2,4-difluorophenyl)piperazin-1-yl)-2-((4-fluorobenzyl)oxy)ethanone (DPFE), ((4-fluorophenyl) (2-(phenoxymethyl)-6,7-dihydrooxazolo[5,4-c]pyridin-5(4H)-yl)methanone) (VU0409551), 3-Cyano-N-(1,3-diphenyl-1H-pyrazol-5-yl)benzamide (CDPPB)] on receptor desensitization and whether cellular context influences receptor regulatory processes. Only VU0424465 and VU0409551 induced desensitization alone in human embryonic kidney 293-mGlu5 cells, while all PAMs enhanced (S)-3,5-dihydroxyphenylglycine (DHPG)-induced desensitization. All mGlu5 PAMs induced receptor desensitization alone and enhanced DHPG-induced desensitization in striatal neurons. VU0424465 and VU0360172 were the only PAMs that induced desensitization alone in cortical neurons. With the exception of (CDPPB), PAMs enhanced DHPG-induced desensitization in cortical neurons. Moreover, differential apparent affinities, efficacies, and cooperativities with DHPG were observed for VU0360172, VU0409551, and VU0424465 when comparing receptor activation and desensitization in a cell type-dependent manner. These data indicate that biased mGlu5 allosteric modulator pharmacology extends to receptor regulatory processes in a tissue dependent manner, adding yet another layer of complexity to rational mGlu5 drug discovery.
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Affiliation(s)
- Shane D Hellyer
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria, Australia
| | - Sabine Albold
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria, Australia
| | - Kathy Sengmany
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria, Australia
| | - Junaid Singh
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria, Australia
| | - Katie Leach
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria, Australia
| | - Karen J Gregory
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria, Australia
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18
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Khoo SYS, LeCocq MR, Deyab GE, Chaudhri N. Context and topography determine the role of basolateral amygdala metabotropic glutamate receptor 5 in appetitive Pavlovian responding. Neuropsychopharmacology 2019; 44:1524-1533. [PMID: 30758331 PMCID: PMC6785093 DOI: 10.1038/s41386-019-0335-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 01/28/2019] [Accepted: 02/03/2019] [Indexed: 01/10/2023]
Abstract
Preclinical data have shown that the excitatory metabotropic Gαq-coupled glutamate receptor, mGluR5, has a role in substance abuse and relapse. However, little is known about the contribution of mGluR5 to the expression of conditioned responding elicited by appetitive Pavlovian cues. We investigated this question in rats that were trained to associate a discrete, auditory conditioned stimulus (CS) with a fructose-glucose solution (5.5% fructose/4.5% glucose; "sugar"). In subsequent tests for the expression of conditioned responding without sugar delivery, CS-elicited fluid port entries were elevated in a context associated with sugar, relative to an equally familiar, neutral context. Inhibiting mGluR5 via systemic injections of a negative allosteric modulator (MTEP; 5 mg/kg) reduced CS port entries in both the sugar context and neutral context. Targeting MTEP microinjections (3 µg/side; 0.3 µl/min) to the nucleus accumbens (Acb) core had no effect on CS port entries at test, whereas the same manipulation in the basolateral amygdala (BLA) produced effects that were topographically dependent. Specifically, microinjecting MTEP in the posterior BLA had no effect on behavior, whereas inhibiting mGluR5 in the anterior BLA enhanced the contextual discrimination of CS port entries. These data are the first to show a role of mGluR5 in the context-dependent expression of appetitive Pavlovian conditioned responding, with a topographically defined arrangement of mGluR5 in the BLA being particularly important for context-based responding to a discrete, appetitive cue.
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Affiliation(s)
- Shaun Yon-Seng Khoo
- 0000 0004 1936 8630grid.410319.eCenter for Studies in Behavioral Neurobiology/FRQS Groupe de recherche en neurobiologie comportementale, Department of Psychology, Concordia University, Quebec, Montreal, Canada
| | - Mandy Rita LeCocq
- 0000 0004 1936 8630grid.410319.eCenter for Studies in Behavioral Neurobiology/FRQS Groupe de recherche en neurobiologie comportementale, Department of Psychology, Concordia University, Quebec, Montreal, Canada
| | - Ghislaine E. Deyab
- 0000 0004 1936 8630grid.410319.eCenter for Studies in Behavioral Neurobiology/FRQS Groupe de recherche en neurobiologie comportementale, Department of Psychology, Concordia University, Quebec, Montreal, Canada
| | - Nadia Chaudhri
- Center for Studies in Behavioral Neurobiology/FRQS Groupe de recherche en neurobiologie comportementale, Department of Psychology, Concordia University, Quebec, Montreal, Canada.
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19
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Jójárt B, Orgován Z, Márki Á, Pándy-Szekeres G, Ferenczy GG, Keserű GM. Allosteric activation of metabotropic glutamate receptor 5. J Biomol Struct Dyn 2019; 38:2624-2632. [DOI: 10.1080/07391102.2019.1638302] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Balázs Jójárt
- Institute of Food Engineering, University of Szeged, Szeged, Hungary
| | - Zoltán Orgován
- Medicinal Chemistry Research Group, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Árpád Márki
- Department of Pharmacodynamics and Biopharmacy, University of Szeged, Szeged, Hungary
| | - Gáspár Pándy-Szekeres
- Medicinal Chemistry Research Group, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - György G. Ferenczy
- Medicinal Chemistry Research Group, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - György M. Keserű
- Medicinal Chemistry Research Group, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
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20
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Yohn SE, Galbraith J, Calipari ES, Conn PJ. Shared Behavioral and Neurocircuitry Disruptions in Drug Addiction, Obesity, and Binge Eating Disorder: Focus on Group I mGluRs in the Mesolimbic Dopamine Pathway. ACS Chem Neurosci 2019; 10:2125-2143. [PMID: 30933466 PMCID: PMC7898461 DOI: 10.1021/acschemneuro.8b00601] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Accumulated data from clinical and preclinical studies suggest that, in drug addiction and states of overeating, such as obesity and binge eating disorder (BED), there is an imbalance in circuits that are critical for motivation, reward saliency, executive function, and self-control. Central to these pathologies and the extensive topic of this Review are the aberrations in dopamine (DA) and glutamate (Glu) within the mesolimbic pathway. Group I metabotropic glutamate receptors (mGlus) are highly expressed in the mesolimbic pathway and are poised in key positions to modulate disruptions in synaptic plasticity and neurotransmitter release observed in drug addiction, obesity, and BED. The use of allosteric modulators of group I mGlus has been studied in drug addiction, as they offer several advantages over traditional orthosteric agents. However, they have yet to be studied in obesity or BED. With the substantial overlap between the neurocircuitry involved in drug addiction and eating disorders, group I mGlus may also provide novel targets for obesity and BED.
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Affiliation(s)
- Samantha E. Yohn
- Department of Pharmacology, Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN, 37232, United States
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, 37232, United States
| | - Jordan Galbraith
- Department of Pharmacology, Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN, 37232, United States
| | - Erin S. Calipari
- Department of Pharmacology, Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN, 37232, United States
| | - P. Jeffrey Conn
- Department of Pharmacology, Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN, 37232, United States
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, 37232, United States
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21
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Nagayach A, Singh A, Geller AI. Separate Gene Transfers into Pre- and Postsynaptic Neocortical Neurons Connected by mGluR5-Containing Synapses. J Mol Neurosci 2019; 68:549-564. [PMID: 30972540 DOI: 10.1007/s12031-019-01317-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 03/28/2019] [Indexed: 11/25/2022]
Abstract
mGluR5-containing synapses have essential roles in synaptic plasticity, circuit physiology, and learning, and dysfunction at these synapses is implicated in specific neurological disorders. As mGluR5-containing synapses are embedded in large and complex distributed circuits containing many neuron and synapse types, it is challenging to elucidate the roles of these synapses and to develop treatments for the associated disorders. Thus, it would be advantageous to deliver different genes into pre- and postsynaptic neurons connected by a mGluR5-containing synapse. Here, we develop this capability: The first gene transfer, into the presynaptic neurons, uses standard techniques to deliver a vector that expresses a synthetic peptide neurotransmitter. This peptide neurotransmitter has three domains: a dense core vesicle sorting domain, a mGluR5-binding domain composed of a single-chain variable fragment anti-mGluR5, and the His tag. Upon release, this peptide neurotransmitter binds to mGluR5, predominately located on the postsynaptic neurons. Selective gene transfer into these neurons uses antibody-mediated, targeted gene transfer and anti-His tag antibodies, as the synthetic peptide neurotransmitter contains the His tag. For the model system, we studied the connection between neurons in two neocortical areas: postrhinal and perirhinal cortices. Targeted gene transfer was over 80% specific for mGluR5-containing synapses, but untargeted gene transfer was only ~ 15% specific for these synapses. This technology may enable studies on the roles of mGluR5-containing neurons and synapses in circuit physiology and learning and support gene therapy treatments for specific disorders that involve dysfunction at these synapses.
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Affiliation(s)
- Aarti Nagayach
- Department of Ophthalmology, Louisiana State University Health Sciences Center, New Orleans, USA
| | - Anshuman Singh
- Department of Ophthalmology, Louisiana State University Health Sciences Center, New Orleans, USA
| | - Alfred I Geller
- Department of Ophthalmology, Louisiana State University Health Sciences Center, New Orleans, USA.
- Department of Pharmacology, Louisiana State University Health Sciences Center, New Orleans, USA.
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22
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Sengmany K, Hellyer SD, Albold S, Wang T, Conn PJ, May LT, Christopoulos A, Leach K, Gregory KJ. Kinetic and system bias as drivers of metabotropic glutamate receptor 5 allosteric modulator pharmacology. Neuropharmacology 2019; 149:83-96. [PMID: 30763654 DOI: 10.1016/j.neuropharm.2019.02.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 01/18/2019] [Accepted: 02/04/2019] [Indexed: 12/17/2022]
Abstract
Allosteric modulators of the metabotropic glutamate receptor subtype 5 (mGlu5) have been proposed as potential therapies for various CNS disorders. These ligands bind to sites distinct from the orthosteric (or endogenous) ligand, often with improved subtype selectivity and spatio-temporal control over receptor responses. We recently revealed that mGlu5 allosteric agonists and positive allosteric modulators exhibit biased agonism and/or modulation. To establish whether negative allosteric modulators (NAMs) engender similar bias, we rigorously characterized the pharmacology of eight diverse mGlu5 NAMs. Radioligand inhibition binding studies revealed novel modes of interaction with mGlu5 for select NAMs, with biphasic or incomplete inhibition of the radiolabeled NAM, [3H]methoxy-PEPy. We assessed mGlu5-mediated intracellular Ca2+ (iCa2+) mobilization and inositol phosphate (IP1) accumulation in HEK293A cells stably expressing low levels of mGlu5 (HEK293A-rat mGlu5-low) and mouse embryonic cortical neurons. The apparent affinity of acetylenic NAMs, MPEP, MTEP and dipraglurant, was dependent on the signaling pathway measured, agonist used, and cell type (HEK293A-rat mGlu5-low versus mouse cortical neurons). In contrast, the acetylenic partial NAM, M-5MPEP, and structurally distinct NAMs (VU0366248, VU0366058, fenobam), had similar affinity estimates irrespective of the assay or cellular background. Biased modulation was evident for VU0366248 in mouse cortical neurons where it was a NAM for DHPG-mediated iCa2+ mobilization, but neutral with DHPG in IP1 accumulation assays. Overall, this study highlights the inherent complexity in mGlu5 NAM pharmacology that we hypothesize may influence interpretation when translating into preclinical models and beyond in the design and development of novel therapeutics for neuropsychiatric and neurological disorders.
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Affiliation(s)
- Kathy Sengmany
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Department of Pharmacology, Monash University, Parkville, VIC, Australia
| | - Shane D Hellyer
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Department of Pharmacology, Monash University, Parkville, VIC, Australia
| | - Sabine Albold
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Department of Pharmacology, Monash University, Parkville, VIC, Australia
| | - Taide Wang
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Department of Pharmacology, Monash University, Parkville, VIC, Australia
| | - P Jeffrey Conn
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Lauren T May
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Department of Pharmacology, Monash University, Parkville, VIC, Australia
| | - Arthur Christopoulos
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Department of Pharmacology, Monash University, Parkville, VIC, Australia
| | - Katie Leach
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Department of Pharmacology, Monash University, Parkville, VIC, Australia
| | - Karen J Gregory
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Department of Pharmacology, Monash University, Parkville, VIC, Australia.
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23
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Graziani D, Caligari S, Callegari E, De Toma C, Longhi M, Frigerio F, Dilernia R, Menegon S, Pinzi L, Pirona L, Tazzari V, Valsecchi AE, Vistoli G, Rastelli G, Riva C. Evaluation of Amides, Carbamates, Sulfonamides, and Ureas of 4-Prop-2-ynylidenecycloalkylamine as Potent, Selective, and Bioavailable Negative Allosteric Modulators of Metabotropic Glutamate Receptor 5. J Med Chem 2019; 62:1246-1273. [PMID: 30624919 DOI: 10.1021/acs.jmedchem.8b01226] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Negative allosteric modulators (NAMs) of the metabotropic glutamate receptor 5 (mGlu5) hold great promise for the treatment of a variety of central nervous system disorders. We have recently reported that prop-2-ynylidenecycloalkylamine derivatives are potent and selective NAMs of the mGlu5 receptor. In this work, we explored the amide, carbamate, sulfonamide, and urea derivatives of prop-2-ynylidenecycloalkylamine compounds with the aim of improving solubility and metabolic stability. In silico and experimental analyses were performed on the synthesized series of compounds to investigate structure-activity relationships. Compounds 12, 32, and 49 of the carbamate, urea, and amide classes, respectively, showed the most suitable cytochrome inhibition and metabolic stability profiles. Among them, compound 12 showed excellent selectivity, solubility, and stability profiles as well as suitable in vitro and in vivo pharmacokinetic properties. It was highly absorbed in rats and dogs and was active in anxiety, neuropathic pain, and lower urinary tract models.
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Affiliation(s)
- Davide Graziani
- Drug Discovery Department , Recordati S.p.A. , Via M. Civitali 1 , 20148 Milan , Italy
| | - Silvia Caligari
- Drug Discovery Department , Recordati S.p.A. , Via M. Civitali 1 , 20148 Milan , Italy
| | - Elisa Callegari
- Drug Discovery Department , Recordati S.p.A. , Via M. Civitali 1 , 20148 Milan , Italy
| | - Carlo De Toma
- Drug Discovery Department , Recordati S.p.A. , Via M. Civitali 1 , 20148 Milan , Italy
| | - Matteo Longhi
- Drug Discovery Department , Recordati S.p.A. , Via M. Civitali 1 , 20148 Milan , Italy
| | - Fabio Frigerio
- Drug Discovery Department , Recordati S.p.A. , Via M. Civitali 1 , 20148 Milan , Italy
| | - Roberto Dilernia
- Drug Discovery Department , Recordati S.p.A. , Via M. Civitali 1 , 20148 Milan , Italy
| | - Sergio Menegon
- Drug Discovery Department , Recordati S.p.A. , Via M. Civitali 1 , 20148 Milan , Italy
| | - Luca Pinzi
- Department of Life Sciences , University of Modena and Reggio Emilia , Via Campi 103 , 41125 Modena , Italy
| | - Lorenza Pirona
- Drug Discovery Department , Recordati S.p.A. , Via M. Civitali 1 , 20148 Milan , Italy
| | - Valerio Tazzari
- Drug Discovery Department , Recordati S.p.A. , Via M. Civitali 1 , 20148 Milan , Italy
| | - Anna Elisa Valsecchi
- Drug Discovery Department , Recordati S.p.A. , Via M. Civitali 1 , 20148 Milan , Italy
| | - Giulio Vistoli
- Department of Pharmaceutical Sciences , Università degli Studi di Milano , Via Mangiagalli 25 , 20133 Milan , Italy
| | - Giulio Rastelli
- Department of Life Sciences , University of Modena and Reggio Emilia , Via Campi 103 , 41125 Modena , Italy
| | - Carlo Riva
- Drug Discovery Department , Recordati S.p.A. , Via M. Civitali 1 , 20148 Milan , Italy
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24
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Chung G, Kim SJ, Kim SK. Metabotropic Glutamate Receptor 5 in the Medial Prefrontal Cortex as a Molecular Determinant of Pain and Ensuing Depression. Front Mol Neurosci 2018; 11:376. [PMID: 30349459 PMCID: PMC6186831 DOI: 10.3389/fnmol.2018.00376] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Accepted: 09/21/2018] [Indexed: 12/27/2022] Open
Abstract
Pain and depression affect one another, and this bidirectional interaction implies the existence of common or interacting neural pathways. Among the neural circuits relevant to negative affection, the medial prefrontal cortex (mPFC) is known to be involved in both pain and depression. Persistent stress from physical pain and mental distress can evoke maladaptive changes in mPFC circuits to induce depression. Conversely, the unpleasant mood condition alters mPFC circuits to distort the appraisal of aversion and make individuals vulnerable to pain. In this article, recent findings regarding mPFC in chronic pain and/or depression are reviewed, with particular focus on the metabotropic glutamate receptor 5 (mGluR5). Although the involvement of mGluR5 within the mPFC in both pain and depressive disorders has been extensively studied, there are controversies regarding changes in the activity of the mPFC during chronic pain and depression, and the functional roles of mGluR5 on altered mPFC activity. We discuss alterations in the availability of mGluR5 in the mPFC in these disorders, its role in behavioral manifestations, and its possible influence on cellular subpopulations that mediate dysfunction in the mPFC. We also propose molecular mechanisms that may cause expressional changes in mGluR5 within the mPFC circuitry.
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Affiliation(s)
- Geehoon Chung
- Department of Physiology, College of Korean Medicine, Kyung Hee University, Seoul, South Korea.,Department of Physiology, College of Medicine, Seoul National University, Seoul, South Korea
| | - Sang Jeong Kim
- Department of Physiology, College of Medicine, Seoul National University, Seoul, South Korea
| | - Sun Kwang Kim
- Department of Physiology, College of Korean Medicine, Kyung Hee University, Seoul, South Korea
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25
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Nasrallah C, Rottier K, Marcellin R, Compan V, Font J, Llebaria A, Pin JP, Banères JL, Lebon G. Direct coupling of detergent purified human mGlu 5 receptor to the heterotrimeric G proteins Gq and Gs. Sci Rep 2018. [PMID: 29535347 PMCID: PMC5849714 DOI: 10.1038/s41598-018-22729-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The metabotropic glutamate (mGlu) receptors are class C G protein-coupled receptors (GPCRs) that modulate synaptic activity and plasticity throughout the mammalian brain. Signal transduction is initiated by glutamate binding to the venus flytrap domains (VFT), which initiates a conformational change that is transmitted to the conserved heptahelical domains (7TM) and results ultimately in the activation of intracellular G proteins. While both mGlu1 and mGlu5 activate Gαq G-proteins, they also increase intracellular cAMP concentration through an unknown mechanism. To study directly the G protein coupling properties of the human mGlu5 receptor homodimer, we purified the full-length receptor, which required careful optimisation of the expression, N-glycosylation and purification. We successfully purified functional mGlu5 that activated the heterotrimeric G protein Gq. The high-affinity agonist-PAM VU0424465 also activated the purified receptor in the absence of an orthosteric agonist. In addition, it was found that purified mGlu5 was capable of activating the G protein Gs either upon stimulation with VU0424465 or glutamate, although the later induced a much weaker response. Our findings provide important mechanistic insights into mGlu5 G protein-dependent activity and selectivity.
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Affiliation(s)
- Chady Nasrallah
- Institut de Génomique Fonctionnelle, Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Montpellier, F-34000, Montpellier, France
| | - Karine Rottier
- Institut de Génomique Fonctionnelle, Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Montpellier, F-34000, Montpellier, France
| | - Romain Marcellin
- Institut de Génomique Fonctionnelle, Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Montpellier, F-34000, Montpellier, France
| | - Vincent Compan
- Institut de Génomique Fonctionnelle, Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Montpellier, F-34000, Montpellier, France
| | - Joan Font
- MCS, Laboratory of Medicinal Chemistry, Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Barcelona, Spain
| | - Amadeu Llebaria
- MCS, Laboratory of Medicinal Chemistry, Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Barcelona, Spain
| | - Jean-Philippe Pin
- Institut de Génomique Fonctionnelle, Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Montpellier, F-34000, Montpellier, France
| | - Jean-Louis Banères
- Institut des Biomolécules Max Mousseron (IBMM), CNRS, Univ. Montpellier, ENSCM, Montpellier, France
| | - Guillaume Lebon
- Institut de Génomique Fonctionnelle, Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Montpellier, F-34000, Montpellier, France.
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26
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Lu S, Zhang J. Small Molecule Allosteric Modulators of G-Protein-Coupled Receptors: Drug–Target Interactions. J Med Chem 2018; 62:24-45. [DOI: 10.1021/acs.jmedchem.7b01844] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Shaoyong Lu
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, School of Medicine, Shanghai Jiao Tong University, Shanghai 200025, China
| | - Jian Zhang
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, School of Medicine, Shanghai Jiao Tong University, Shanghai 200025, China
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27
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Leurquin-Sterk G, Ceccarini J, Crunelle CL, de Laat B, Verbeek J, Deman S, Neels H, Bormans G, Peuskens H, Van Laere K. Lower Limbic Metabotropic Glutamate Receptor 5 Availability in Alcohol Dependence. J Nucl Med 2018; 59:682-690. [PMID: 29348321 DOI: 10.2967/jnumed.117.199422] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 10/30/2017] [Indexed: 01/18/2023] Open
Abstract
Animal studies suggest an important role for the metabotropic glutamate receptor subtype 5 (mGlu5) in the pathophysiology of alcohol dependence, but direct human evidence is lacking. The goal of this study was to investigate cerebral mGlu5 availability in alcohol-dependent subjects versus controls using 18F-3-fluoro-5-[(pyridin-3-yl)ethynyl]benzonitrile (18F-FPEB) PET. Methods: Dynamic 90-min 18F-FPEB scans combined with arterial blood sampling were acquired for 16 recently abstinent alcohol-dependent subjects and 32 age-matched controls. Regional mGlu5 availability was quantified by the 18F-FPEB total distribution volume using both a voxel-by-voxel and a volume-of-interest analysis with partial-volume effect correction. Alcohol consumption within the last 3 mo was assessed by questionnaires and by hair ethyl glucuronide analysis. Craving was assessed using the Desire for Alcohol Questionnaire. Results: mGlu5 availability was lower in mainly limbic regions of alcohol-dependent subjects than in controls (P < 0.05, familywise error-corrected), ranging from 14% in the posterior cingulate cortex to 36% in the caudate nucleus. Lower mGlu5 availability was associated with higher hair ethyl glucuronide levels for most regions and was related to a lower level of craving specifically in the middle frontal gyrus, cingulate cortex, and inferolateral temporal lobe. Conclusion: These findings provide human in vivo evidence that limbic mGlu5 has a role in the pathophysiology of alcohol dependence, possibly involved in a compensatory mechanism helping to reduce craving during abstinence.
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Affiliation(s)
- Gil Leurquin-Sterk
- Division of Nuclear Medicine and Molecular Imaging, Department of Imaging and Pathology, KU Leuven, Leuven, Belgium
| | - Jenny Ceccarini
- Division of Nuclear Medicine and Molecular Imaging, Department of Imaging and Pathology, KU Leuven, Leuven, Belgium
| | - Cleo L Crunelle
- Toxicological Center, University of Antwerp, Wilrijk, Belgium.,Department of Psychiatry, University Hospital Brussels, Brussels, Belgium
| | - Bart de Laat
- Division of Nuclear Medicine and Molecular Imaging, Department of Imaging and Pathology, KU Leuven, Leuven, Belgium.,MoSAIC: Molecular Small Animal Imaging Center, KU Leuven, Leuven, Belgium
| | - Jef Verbeek
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Stephanie Deman
- Genomics Core, UZ Leuven, and Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - Hugo Neels
- Toxicological Center, University of Antwerp, Wilrijk, Belgium
| | - Guy Bormans
- Laboratory for Radiopharmacy, KU Leuven, Leuven, Belgium; and
| | - Hendrik Peuskens
- University Psychiatric Center, KU Leuven, Kortenberg, and Kliniek Broeders Alexianen, Tienen, Belgium
| | - Koen Van Laere
- Division of Nuclear Medicine and Molecular Imaging, Department of Imaging and Pathology, KU Leuven, Leuven, Belgium.,MoSAIC: Molecular Small Animal Imaging Center, KU Leuven, Leuven, Belgium
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28
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Abstract
This themed issue of the British Journal of Pharmacology stems from the eighth in the series of meetings on the Molecular Pharmacology of G protein coupled receptors (MPGPCR) held as part of a joint meeting with the Australasian Society of Clinical and Experimental Pharmacologists and Toxicologists (ASCEPT) in Melbourne Australia from 7 to 11 December 2014. Linked Articles This article is part of a themed section on Molecular Pharmacology of G Protein-Coupled Receptors. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v173.20/issuetoc.
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Affiliation(s)
- R J Summers
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia.
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29
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Park JY, Son J, Yun M, Ametamey SM, Chun JH. Automated cGMP-compliant radiosynthesis of [ 18 F]-(E)-PSS232 for brain PET imaging of metabotropic glutamate receptor subtype 5. J Labelled Comp Radiopharm 2017; 61:30-37. [PMID: 28948638 DOI: 10.1002/jlcr.3566] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Revised: 09/12/2017] [Accepted: 09/15/2017] [Indexed: 11/10/2022]
Abstract
(E)-3-(Pyridin-2-yl ethynyl)cyclohex-2-enone O-(3-(2-[18 F]-fluoroethoxy)propyl) oxime ([18 F]-(E)-PSS232, [18 F]2a) is a recently developed radiotracer that can be used to visualize metabotropic glutamate receptor subtype 5 (mGlu5 ) in vivo. The mGlu5 has become an attractive therapeutic and diagnostic target owing to its role in many neuropsychiatric disorders. Several carbon-11-labeled and fluorine-18-labeled radiotracers have been developed to measure mGlu5 receptor occupancy in the human brain. The radiotracer [18 F]2a, which is used as an analogue for [11 C]ABP688 ([11 C]1) and has a longer physical half-life, is a selective radiotracer that exhibits high binding affinity for mGlu5 . Herein, we report the fully automated radiosynthesis of [18 F]2a using a commercial GE TRACERlab™ FX-FN synthesizer for routine production and distribution to nearby satellite clinics. Nucleophilic substitution of the corresponding mesylate precursor with cyclotron-produced [18 F]fluoride ion at 100°C in dimethyl sulfoxide (DMSO), followed by high-performance liquid chromatography (HPLC) purification and formulation, readily provided [18 F]2a with a radiochemical yield of 40 ± 2% (decay corrected, n = 5) at the end of synthesis. Radiochemical purity for the [18 F]-(E)-conformer was greater than 95%. Molar activity was determined to be 63.6 ± 9.6 GBq/μmol (n = 5), and the overall synthesis time was 70 minutes.
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Affiliation(s)
- Jun Young Park
- Department of Nuclear Medicine, Severance Hospital, Yonsei University Health System, Seoul, Republic of Korea
| | - Jeongmin Son
- Department of Nuclear Medicine, Severance Hospital, Yonsei University Health System, Seoul, Republic of Korea
| | - Mijin Yun
- Department of Nuclear Medicine, Severance Hospital, Yonsei University Health System, Seoul, Republic of Korea.,Department of Nuclear Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Simon M Ametamey
- Department of Applied Biosciences of ETH Zurich, Center for Radiopharmaceutical Sciences of ETH, PSI, and USZ, Zurich, Switzerland
| | - Joong-Hyun Chun
- Department of Nuclear Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
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30
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Glutamate-Dependent Translational Control of Glutamine Synthetase in Bergmann Glia Cells. Mol Neurobiol 2017; 55:5202-5209. [PMID: 28875233 DOI: 10.1007/s12035-017-0756-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 08/24/2017] [Indexed: 12/12/2022]
Abstract
Glutamate is the major excitatory transmitter of the vertebrate brain. It exerts its actions through the activation of specific plasma membrane receptors expressed both in neurons and in glial cells. Recent evidence has shown that glutamate uptake systems, particularly enriched in glia cells, trigger biochemical cascades in a similar fashion as receptors. A tight regulation of glutamate extracellular levels prevents neuronal overstimulation and cell death, and it is critically involved in glutamate turnover. Glial glutamate transporters are responsible of the majority of the brain glutamate uptake activity. Once internalized, this excitatory amino acid is rapidly metabolized to glutamine via the astrocyte-enriched enzyme glutamine synthetase. A coupling between glutamate uptake and glutamine synthesis and release has been commonly known as the glutamate/glutamine shuttle. Taking advantage of the established model of cultured Bergmann glia cells, in this contribution, we explored the gene expression regulation of glutamine synthetase. A time- and dose-dependent regulation of glutamine synthetase protein and activity levels was found. Moreover, glutamate exposure resulted in the transient shift of glutamine synthetase mRNA from the monosomal to the polysomal fraction. These results demonstrate a novel mode of glutamate-dependent glutamine synthetase regulation and strengthen the notion of an exquisite glia neuronal interaction in glutamatergic synapses.
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31
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Harpsøe K, Boesgaard MW, Munk C, Bräuner-Osborne H, Gloriam DE. Structural insight to mutation effects uncover a common allosteric site in class C GPCRs. Bioinformatics 2017; 33:1116-1120. [PMID: 28011766 PMCID: PMC5408886 DOI: 10.1093/bioinformatics/btw784] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 12/07/2016] [Indexed: 01/08/2023] Open
Abstract
Motivation Class C G protein-coupled receptors (GPCRs) regulate important physiological functions and allosteric modulators binding to the transmembrane domain constitute an attractive and, due to a lack of structural insight, a virtually unexplored potential for therapeutics and the food industry. Combining pharmacological site-directed mutagenesis data with the recent class C GPCR experimental structures will provide a foundation for rational design of new therapeutics. Results We uncover one common site for both positive and negative modulators with different amino acid layouts that can be utilized to obtain selectivity. Additionally, we show a large potential for structure-based modulator design, especially for four orphan receptors with high similarity to the crystal structures. Availability and Implementation All collated mutagenesis data is available in the GPCRdb mutation browser at http://gpcrdb.org/mutations/ and can be analyzed online or downloaded in excel format. Supplementary information Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Kasper Harpsøe
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Michael W Boesgaard
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Christian Munk
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Hans Bräuner-Osborne
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - David E Gloriam
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- To whom correspondence should be addressed.
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32
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Lecat-Guillet N, Monnier C, Rovira X, Kniazeff J, Lamarque L, Zwier JM, Trinquet E, Pin JP, Rondard P. FRET-Based Sensors Unravel Activation and Allosteric Modulation of the GABA B Receptor. Cell Chem Biol 2017; 24:360-370. [PMID: 28286129 DOI: 10.1016/j.chembiol.2017.02.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 11/21/2016] [Accepted: 02/10/2017] [Indexed: 01/11/2023]
Abstract
The main inhibitory neurotransmitter, γ-aminobutyric acid (GABA), modulates many synapses by activating the G protein-coupled receptor GABAB, which is a target for various therapeutic applications. It is an obligatory heterodimer made of GB1 and GB2 that can be regulated by positive allosteric modulators (PAMs). The molecular mechanism of activation of the GABAB receptor remains poorly understood. Here, we have developed FRET-based conformational GABAB sensors compatible with high-throughput screening. We identified conformational changes occurring within the extracellular and transmembrane domains upon receptor activation, which are smaller than those observed in the related metabotropic glutamate receptors. These sensors also allow discrimination between agonists of different efficacies and between PAMs that have different modes of action, which has not always been possible using conventional functional assays. Our study brings important new information on the activation mechanism of the GABAB receptor and should facilitate the screening and identification of new chemicals targeting this receptor.
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Affiliation(s)
- Nathalie Lecat-Guillet
- Institut de Génomique Fonctionnelle (IGF), CNRS, INSERM, University of Montpellier, 141 rue de la Cardonille, 34094 Montpellier, France
| | - Carine Monnier
- Institut de Génomique Fonctionnelle (IGF), CNRS, INSERM, University of Montpellier, 141 rue de la Cardonille, 34094 Montpellier, France
| | - Xavier Rovira
- Institut de Génomique Fonctionnelle (IGF), CNRS, INSERM, University of Montpellier, 141 rue de la Cardonille, 34094 Montpellier, France
| | - Julie Kniazeff
- Institut de Génomique Fonctionnelle (IGF), CNRS, INSERM, University of Montpellier, 141 rue de la Cardonille, 34094 Montpellier, France
| | | | | | | | - Jean-Philippe Pin
- Institut de Génomique Fonctionnelle (IGF), CNRS, INSERM, University of Montpellier, 141 rue de la Cardonille, 34094 Montpellier, France
| | - Philippe Rondard
- Institut de Génomique Fonctionnelle (IGF), CNRS, INSERM, University of Montpellier, 141 rue de la Cardonille, 34094 Montpellier, France.
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33
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Gregory KJ, Velagaleti R, Thal DM, Brady RM, Christopoulos A, Conn PJ, Lapinsky DJ. Clickable Photoaffinity Ligands for Metabotropic Glutamate Receptor 5 Based on Select Acetylenic Negative Allosteric Modulators. ACS Chem Biol 2016; 11:1870-9. [PMID: 27115427 DOI: 10.1021/acschembio.6b00026] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
G protein-coupled receptors (GPCRs) represent the largest class of current drug targets. In particular, small-molecule allosteric modulators offer substantial potential for selectively "tuning" GPCR activity. However, there remains a critical need for experimental strategies that unambiguously determine direct allosteric ligand-GPCR interactions, to facilitate both chemical biology studies and rational structure-based drug design. We now report the development and use of first-in-class clickable allosteric photoprobes for a GPCR based on metabotropic glutamate receptor 5 (mGlu5) negative allosteric modulator (NAM) chemotypes. Select acetylenic mGlu5 NAM lead compounds were rationally modified to contain either a benzophenone or an aryl azide as a photoreactive functional group, enabling irreversible covalent attachment to mGlu5 via photoactivation. Additionally, a terminal alkyne or an aliphatic azide was incorporated as a click chemistry handle, allowing chemoselective attachment of fluorescent moieties to the irreversibly mGlu5-bound probe via tandem photoaffinity labeling-bioorthogonal conjugation. These clickable photoprobes retained submicromolar affinity for mGlu5 and negative cooperativity with glutamate, interacted with the "common allosteric-binding site," displayed slow binding kinetics, and could irreversibly label mGlu5 following UV exposure. We depleted the number of functional mGlu5 receptors using an irreversibly bound NAM to elucidate and delineate orthosteric agonist affinity and efficacy. Finally, successful conjugation of fluorescent dyes via click chemistry was demonstrated for each photoprobe. In the future, these clickable photoprobes are expected to aid our understanding of the structural basis of mGlu5 allosteric modulation. Furthermore, tandem photoaffinity labeling-bioorthogonal conjugation is expected to be a broadly applicable experimental strategy across the entire GPCR superfamily.
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Affiliation(s)
- Karen J. Gregory
- Drug
Discovery Biology, Monash Institute of Pharmaceutical Sciences and
Department of Pharmacology, Monash University, Parkville, Victoria, Australia
| | - Ranganadh Velagaleti
- Division
of Pharmaceutical Sciences, Mylan School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania, United States
| | - David M. Thal
- Drug
Discovery Biology, Monash Institute of Pharmaceutical Sciences and
Department of Pharmacology, Monash University, Parkville, Victoria, Australia
| | - Ryan M. Brady
- Drug
Discovery Biology, Monash Institute of Pharmaceutical Sciences and
Department of Pharmacology, Monash University, Parkville, Victoria, Australia
| | - Arthur Christopoulos
- Drug
Discovery Biology, Monash Institute of Pharmaceutical Sciences and
Department of Pharmacology, Monash University, Parkville, Victoria, Australia
| | - P. Jeffrey Conn
- Vanderbilt
Center for Neuroscience Drug Discovery and Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee, United States
| | - David J. Lapinsky
- Division
of Pharmaceutical Sciences, Mylan School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania, United States
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34
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Biased allosteric agonism and modulation of metabotropic glutamate receptor 5: Implications for optimizing preclinical neuroscience drug discovery. Neuropharmacology 2016; 115:60-72. [PMID: 27392634 DOI: 10.1016/j.neuropharm.2016.07.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 06/30/2016] [Accepted: 07/01/2016] [Indexed: 12/20/2022]
Abstract
Allosteric modulators, that exhibit no intrinsic agonist activity, offer the advantage of spatial and temporal fine-tuning of endogenous agonist activity, allowing the potential for increased selectivity, reduced adverse effects and improved clinical outcomes. Some allosteric ligands can differentially activate and/or modulate distinct signaling pathways arising from the same receptor, phenomena referred to as 'biased agonism' and 'biased modulation'. Emerging evidence for CNS disorders with glutamatergic dysfunction suggests the metabotropic glutamate receptor subtype 5 (mGlu5) is a promising target. Current mGlu5 allosteric modulators have largely been classified based on modulation of intracellular calcium (iCa2+) responses to orthosteric agonists alone. We assessed eight mGlu5 allosteric modulators previously classified as mGlu5 PAMs or PAM-agonists representing four distinct chemotypes across multiple measures of receptor activity, to explore their potential for engendering biased agonism and/or modulation. Relative to the reference orthosteric agonist, DHPG, the eight allosteric ligands exhibited distinct biased agonism fingerprints for iCa2+ mobilization, IP1 accumulation and ERK1/2 phosphorylation in HEK293A cells stably expressing mGlu5 and in cortical neuron cultures. VU0424465, DPFE and VU0409551 displayed the most disparate biased signaling fingerprints in both HEK293A cells and cortical neurons that may account for the marked differences observed previously for these ligands in vivo. Select mGlu5 allosteric ligands also showed 'probe dependence' with respect to their cooperativity with different orthosteric agonists, as well as biased modulation for the magnitude of positive cooperativity observed. Unappreciated biased agonism and modulation may contribute to unanticipated effects (both therapeutic and adverse) when translating from recombinant systems to preclinical models. This article is part of the Special Issue entitled 'Metabotropic Glutamate Receptors, 5 years on'.
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35
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Metabotropic glutamate receptor 5 – a promising target in drug development and neuroimaging. Eur J Nucl Med Mol Imaging 2016; 43:1151-70. [DOI: 10.1007/s00259-015-3301-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2015] [Accepted: 12/22/2015] [Indexed: 10/22/2022]
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36
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Sengmany K, Gregory KJ. Metabotropic glutamate receptor subtype 5: molecular pharmacology, allosteric modulation and stimulus bias. Br J Pharmacol 2015; 173:3001-17. [PMID: 26276909 DOI: 10.1111/bph.13281] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Revised: 06/30/2015] [Accepted: 07/26/2015] [Indexed: 12/12/2022] Open
Abstract
The metabotropic glutamate receptor subtype 5 (mGlu5 ) is a family C GPCR that has been implicated in various neuronal processes and, consequently, in several CNS disorders. Over the past few decades, GPCR-based drug discovery, including that for mGlu5 receptors, has turned considerable attention to targeting allosteric binding sites. Modulation of endogenous agonists by allosteric ligands offers the advantages of spatial and temporal fine-tuning of receptor activity, increased selectivity and reduced adverse effects with the potential to elicit improved clinical outcomes. Further, with greater appreciation of the multifaceted nature of the transduction of mGlu5 receptor signalling, it is increasingly apparent that drug discovery must take into consideration unique receptor conformations and the potential for stimulus-bias. This novel paradigm proposes that different ligands may differentially modulate distinct signalling pathways arising from the same receptor. We review our current understanding of the complexities of mGlu5 receptor signalling and regulation, and how these relate to allosteric ligands. Ultimately, a deeper appreciation of these relationships will provide the foundation for targeted drug design of compounds with increased selectivity, not only for the desired receptor but also for the desired signalling outcome from the receptor. Linked Articles This article is part of a themed section on Molecular Pharmacology of G Protein-Coupled Receptors. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v173.20/issuetoc.
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Affiliation(s)
- K Sengmany
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, VIC, Australia
| | - K J Gregory
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, VIC, Australia.
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