1
|
Nicoletti F, Di Menna L, Iacovelli L, Orlando R, Zuena AR, Conn PJ, Dogra S, Joffe ME. GPCR interactions involving metabotropic glutamate receptors and their relevance to the pathophysiology and treatment of CNS disorders. Neuropharmacology 2023; 235:109569. [PMID: 37142158 DOI: 10.1016/j.neuropharm.2023.109569] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 04/18/2023] [Accepted: 05/02/2023] [Indexed: 05/06/2023]
Abstract
Cellular responses to metabotropic glutamate (mGlu) receptor activation are shaped by mechanisms of receptor-receptor interaction. mGlu receptor subtypes form homodimers, intra- or inter-group heterodimers, and heteromeric complexes with other G protein-coupled receptors (GPCRs). In addition, mGlu receptors may functionally interact with other receptors through the βγ subunits released from G proteins in response to receptor activation or other mechanisms. Here, we discuss the interactions between (i) mGlu1 and GABAB receptors in cerebellar Purkinje cells; (ii) mGlu2 and 5-HT2Aserotonergic receptors in the prefrontal cortex; (iii) mGlu5 and A2A receptors or mGlu5 and D1 dopamine receptors in medium spiny projection neurons of the indirect and direct pathways of the basal ganglia motor circuit; (iv) mGlu5 and A2A receptors in relation to the pathophysiology of Alzheimer's disease; and (v) mGlu7 and A1 adenosine or α- or β1 adrenergic receptors. In addition, we describe in detail a novel form of non-heterodimeric interaction between mGlu3 and mGlu5 receptors, which appears to be critically involved in mechanisms of activity-dependent synaptic plasticity in the prefrontal cortex and hippocampus. Finally, we highlight the potential implication of these interactions in the pathophysiology and treatment of cerebellar disorders, schizophrenia, Alzheimer's disease, Parkinson's disease, l-DOPA-induced dyskinesias, stress-related disorders, and cognitive dysfunctions.
Collapse
Affiliation(s)
- Ferdinando Nicoletti
- Department of Physiology and Pharmacology, Sapienza University of Rome, Italy; IRCCS Neuromed, Pozzilli, Italy.
| | | | - Luisa Iacovelli
- Department of Physiology and Pharmacology, Sapienza University of Rome, Italy
| | - Rosamaria Orlando
- Department of Physiology and Pharmacology, Sapienza University of Rome, Italy; IRCCS Neuromed, Pozzilli, Italy
| | - Anna Rita Zuena
- Department of Physiology and Pharmacology, Sapienza University of Rome, Italy
| | - P Jeffrey Conn
- Department of Pharmacology, Italy; Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, 37232, USA
| | - Shalini Dogra
- Department of Pharmacology, Italy; Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, 37232, USA
| | - Max E Joffe
- Translational Neuroscience Program, Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, 15219, USA
| |
Collapse
|
2
|
Di Menna L, Joffe ME, Iacovelli L, Orlando R, Lindsley CW, Mairesse J, Gressèns P, Cannella M, Caraci F, Copani A, Bruno V, Battaglia G, Conn PJ, Nicoletti F. Functional partnership between mGlu3 and mGlu5 metabotropic glutamate receptors in the central nervous system. Neuropharmacology 2017; 128:301-313. [PMID: 29079293 DOI: 10.1016/j.neuropharm.2017.10.026] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 10/09/2017] [Accepted: 10/21/2017] [Indexed: 12/19/2022]
Abstract
mGlu5 receptors are involved in mechanisms of activity-dependent synaptic plasticity, and are targeted by drugs developed for the treatment of CNS disorders. We report that mGlu3 receptors, which are traditionally linked to the control of neurotransmitter release, support mGlu5 receptor signaling in neurons and largely contribute to the robust mGlu5 receptor-mediated polyphosphoinositide hydrolysis in the early postnatal life. In cortical pyramidal neurons, mGlu3 receptor activation potentiated mGlu5 receptor-mediated somatic Ca2+ mobilization, and mGlu3 receptor-mediated long-term depression in the prefrontal cortex required the endogenous activation of mGlu5 receptors. The interaction between mGlu3 and mGlu5 receptors was also relevant to mechanisms of neuronal toxicity, with mGlu3 receptors shaping the influence of mGlu5 receptors on excitotoxic neuronal death. These findings shed new light into the complex role played by mGlu receptors in physiology and pathology, and suggest reconsideration of some of the current dogmas in the mGlu receptor field.
Collapse
Affiliation(s)
| | - Max E Joffe
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, TN 37232-0697, USA
| | - Luisa Iacovelli
- Department of Physiology and Pharmacology, University Sapienza of Roma, 00185 Roma, Italy
| | - Rosamaria Orlando
- Department of Physiology and Pharmacology, University Sapienza of Roma, 00185 Roma, Italy
| | - Craig W Lindsley
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, TN 37232-0697, USA
| | - Jèrome Mairesse
- PROTECT, INSERM, Université Paris Diderot, Sorbonne Paris Cité, 1141 Paris, France
| | - Pierre Gressèns
- PROTECT, INSERM, Université Paris Diderot, Sorbonne Paris Cité, 1141 Paris, France; Centre for the Developing Brain, Department of Perinatal Health and Imaging, Division of Imaging Sciences and Biomedical Engineering, King's College London, King's Health Partners, St. Thomas' Hospital, London SE1 7EH, United Kingdom
| | | | - Filippo Caraci
- Department of Drug Sciences, University of Catania, 95125 Catania, Italy; I.R.C.C.S. Oasi Maria SS, 94018 Troina, Italy
| | - Agata Copani
- Department of Drug Sciences, University of Catania, 95125 Catania, Italy; Institute of Biostructure and Bioimaging, National Research Council, 95126 Catania, Italy
| | - Valeria Bruno
- I.R.C.C.S. Neuromed, 86077 Pozzilli, Italy; Department of Physiology and Pharmacology, University Sapienza of Roma, 00185 Roma, Italy
| | | | - P Jeffrey Conn
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, TN 37232-0697, USA
| | - Ferdinando Nicoletti
- I.R.C.C.S. Neuromed, 86077 Pozzilli, Italy; Department of Physiology and Pharmacology, University Sapienza of Roma, 00185 Roma, Italy.
| |
Collapse
|
3
|
Bruno V, Caraci F, Copani A, Matrisciano F, Nicoletti F, Battaglia G. The impact of metabotropic glutamate receptors into active neurodegenerative processes: A "dark side" in the development of new symptomatic treatments for neurologic and psychiatric disorders. Neuropharmacology 2016; 115:180-192. [PMID: 27140693 DOI: 10.1016/j.neuropharm.2016.04.044] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 04/22/2016] [Accepted: 04/28/2016] [Indexed: 12/17/2022]
Abstract
Metabotropic glutamate (mGlu) receptor ligands are under clinical development for the treatment of CNS disorders with high social and economic burden, such as schizophrenia, major depressive disorder (MDD), and Parkinson's disease (PD), and are promising drug candidates for the treatment of Alzheimer's disease (AD). So far, clinical studies have shown symptomatic effects of mGlu receptor ligands, but it is unknown whether these drugs act as disease modifiers or, at the opposite end, they accelerate disease progression by enhancing neurodegeneration. This is a fundamental issue in the treatment of PD and AD, and is also an emerging theme in the treatment of schizophrenia and MDD, in which neurodegeneration is also present and contribute to disease progression. Moving from in vitro data and preclinical studies, we discuss the potential impact of drugs targeting mGlu2, mGlu3, mGlu4 and mGlu5 receptor ligands on active neurodegeneration associated with AD, PD, schizophrenia, and MDD. We wish to highlight that our final comments on the best drug candidates are not influenced by commercial interests or by previous or ongoing collaborations with drug companies. This article is part of the Special Issue entitled 'Metabotropic Glutamate Receptors, 5 years on'.
Collapse
Affiliation(s)
- Valeria Bruno
- Department of Physiology and Pharmacology, University Sapienza, 00185 Rome, Italy; I.R.C.C.S. Neuromed, 86077 Pozzilli, Italy.
| | - Filippo Caraci
- Department of Drug Sciences, University of Catania, 95125 Catania, Italy; I.R.C.C.S. Associazione Oasi Maria S.S., Institute for Research on Mental Retardation and Brain Aging, 94018 Troina, Italy
| | - Agata Copani
- Department of Drug Sciences, University of Catania, 95125 Catania, Italy; National Research Council, Institute of Biostructure and Bioimaging (IBB-CNR), 95126 Catania, Italy
| | - Francesco Matrisciano
- Department of Psychiatry and Behavioral Sciences, Northwestern Feinberg School of Medicine, Chicago, USA
| | - Ferdinando Nicoletti
- Department of Physiology and Pharmacology, University Sapienza, 00185 Rome, Italy; I.R.C.C.S. Neuromed, 86077 Pozzilli, Italy
| | | |
Collapse
|
4
|
Fazio F, Lionetto L, Curto M, Iacovelli L, Cavallari M, Zappulla C, Ulivieri M, Napoletano F, Capi M, Corigliano V, Scaccianoce S, Caruso A, Miele J, De Fusco A, Di Menna L, Comparelli A, De Carolis A, Gradini R, Nisticò R, De Blasi A, Girardi P, Bruno V, Battaglia G, Nicoletti F, Simmaco M. Xanthurenic Acid Activates mGlu2/3 Metabotropic Glutamate Receptors and is a Potential Trait Marker for Schizophrenia. Sci Rep 2015; 5:17799. [PMID: 26643205 PMCID: PMC4672300 DOI: 10.1038/srep17799] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 11/06/2015] [Indexed: 11/09/2022] Open
Abstract
The kynurenine pathway of tryptophan metabolism has been implicated in the pathophysiology of psychiatric disorders, including schizophrenia. We report here that the kynurenine metabolite, xanturenic acid (XA), interacts with, and activates mGlu2 and mGlu3 metabotropic glutamate receptors in heterologous expression systems. However, the molecular nature of this interaction is unknown, and our data cannot exclude that XA acts primarily on other targets, such as the vesicular glutamate transporter, in the CNS. Systemic administration of XA in mice produced antipsychotic-like effects in the MK-801-induced model of hyperactivity. This effect required the presence of mGlu2 receptors and was abrogated by the preferential mGlu2/3 receptor antagonist, LY341495. Because the mGlu2 receptor is a potential drug target in the treatment of schizophrenia, we decided to measure serum levels of XA and other kynurenine metabolites in patients affected by schizophrenia. Serum XA levels were largely reduced in a large cohort of patients affected by schizophrenia, and, in patients with first-episode schizophrenia, levels remained low after 12 months of antipsychotic medication. As opposed to other kynurenine metabolites, XA levels were also significantly reduced in first-degree relatives of patients affected by schizophrenia. We suggest that lowered serum XA levels might represent a novel trait marker for schizophrenia.
Collapse
Affiliation(s)
| | - Luana Lionetto
- Advanced Molecular Diagnostics Unit, Sant'Andrea Hospital, Rome, Italy
| | - Martina Curto
- School of Medicine and Psychology NESMOS Department, Sant'Andrea Hospital, Sapienza University, Rome, Italy
| | - Luisa Iacovelli
- Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
| | - Michele Cavallari
- School of Medicine and Psychology NESMOS Department, Sant'Andrea Hospital, Sapienza University, Rome, Italy.,Center for Neurological Imaging, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, U.S.A
| | | | - Martina Ulivieri
- Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
| | - Flavia Napoletano
- School of Medicine and Psychology NESMOS Department, Sant'Andrea Hospital, Sapienza University, Rome, Italy
| | - Matilde Capi
- School of Medicine and Psychology NESMOS Department, Sant'Andrea Hospital, Sapienza University, Rome, Italy
| | - Valentina Corigliano
- School of Medicine and Psychology NESMOS Department, Sant'Andrea Hospital, Sapienza University, Rome, Italy
| | - Sergio Scaccianoce
- Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
| | - Alessandra Caruso
- Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
| | - Jessica Miele
- Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
| | | | | | - Anna Comparelli
- School of Medicine and Psychology NESMOS Department, Sant'Andrea Hospital, Sapienza University, Rome, Italy
| | - Antonella De Carolis
- School of Medicine and Psychology NESMOS Department, Sant'Andrea Hospital, Sapienza University, Rome, Italy
| | - Roberto Gradini
- I.R.C.C.S. Neuromed, Pozzilli, Italy.,Department of Experimental Medicine, Sapienza University, Rome, Italy
| | - Robert Nisticò
- Department of Physiology and Pharmacology, Sapienza University, Rome, Italy.,I.R.C.C.S. Fondazione Santa Lucia, Rome, Italy
| | - Antonio De Blasi
- Department of Molecular Medicine, Sapienza University, Rome, Italy
| | - Paolo Girardi
- School of Medicine and Psychology NESMOS Department, Sant'Andrea Hospital, Sapienza University, Rome, Italy
| | - Valeria Bruno
- I.R.C.C.S. Neuromed, Pozzilli, Italy.,Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
| | | | - Ferdinando Nicoletti
- I.R.C.C.S. Neuromed, Pozzilli, Italy.,Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
| | - Maurizio Simmaco
- Advanced Molecular Diagnostics Unit, Sant'Andrea Hospital, Rome, Italy.,School of Medicine and Psychology NESMOS Department, Sant'Andrea Hospital, Sapienza University, Rome, Italy
| |
Collapse
|
5
|
Nicoletti F, Bockaert J, Collingridge GL, Conn PJ, Ferraguti F, Schoepp DD, Wroblewski JT, Pin JP. Metabotropic glutamate receptors: from the workbench to the bedside. Neuropharmacology 2010; 60:1017-41. [PMID: 21036182 DOI: 10.1016/j.neuropharm.2010.10.022] [Citation(s) in RCA: 476] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Revised: 10/15/2010] [Accepted: 10/21/2010] [Indexed: 12/24/2022]
Abstract
Metabotropic glutamate (mGlu) receptors were discovered in the mid 1980s and originally described as glutamate receptors coupled to polyphosphoinositide hydrolysis. Almost 6500 articles have been published since then, and subtype-selective mGlu receptor ligands are now under clinical development for the treatment of a variety of disorders such as Fragile-X syndrome, schizophrenia, Parkinson's disease and L-DOPA-induced dyskinesias, generalized anxiety disorder, chronic pain, and gastroesophageal reflux disorder. Prof. Erminio Costa was linked to the early times of the mGlu receptor history, when a few research groups challenged the general belief that glutamate could only activate ionotropic receptors and all metabolic responses to glutamate were secondary to calcium entry. This review moves from those nostalgic times to the most recent advances in the physiology and pharmacology of mGlu receptors, and highlights the role of individual mGlu receptor subtypes in the pathophysiology of human disorders. This article is part of a Special Issue entitled 'Trends in neuropharmacology: in memory of Erminio Costa'.
Collapse
Affiliation(s)
- F Nicoletti
- Department of Physiology and Pharmacology, University of Rome, Sapienza, Piazzale Aldo Moro 5, 00185 Rome, Italy.
| | | | | | | | | | | | | | | |
Collapse
|
6
|
Thomas AG, Bodner A, Ghadge G, Roos RP, Slusher BS. GCP II inhibition rescues neurons from gp120IIIB-induced neurotoxicity. J Neurovirol 2010; 15:449-57. [PMID: 19995130 DOI: 10.3109/13550280903350598] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Excessive glutamate neurotransmission has been implicated in neuronal injury in many disorders of the central nervous system (CNS), including human immunodeficiency virus (HIV)-associated dementia. Gp120IIIB is a strain of a HIV glycoprotein with specificity for the CXCR4 receptor that induces neuronal apoptosis in in vitro models of acquired immunodeficiency syndrome (AIDS)-induced neurodegeneration. Since the catabolism of the neuropeptide N-acetylaspartylglutamate (NAAG) by glutamate carboxypeptidase (GCP) II increases cellular glutamate, an event associated with excitotoxicity, we hypothesized that inhibition of GCP II may prevent gp120IIIB-induced cell death. Furthermore, through GCP II inhibition, increased NAAG may be neuroprotective via its agonist effects at the mGlu(3) receptor. To ascertain the therapeutic potential of GCP II inhibitors, embryonic day 17 hippocampal cultures were exposed to gp120IIIB in the presence of a potent and highly selective GCP II inhibitor, 2-(phosphonomethyl)-pentanedioic acid (2-PMPA). 2-PMPA was found to abrogate gp120IIIB-induced toxicity in a dose-dependent manner. Additionally, 2-PMPA was neuroprotective when applied up to 2 h after the application of gp120IIIB. The abrogation of apoptosis by 2-PMPA was reversed with administration of mGlu(3) receptor antagonists and with antibodies to transforming growth factor (TGF)-beta. Further, consistent with the localization of GCP II, 2-PMPA failed to provide neuroprotection in the absence of glia. GCP II activity and its inhibition by 2-PMPA were confirmed in the hippocampal cultures using radiolabeled NAAG and high-performance liquid chromatography (HPLC) analysis. Taken together, these data suggest that GCP II is involved in mediating gp120-induced apoptosis in hippocampal neurons and GCP II inhibitors may have potential in the treatment of neuronal injury related to AIDS.
Collapse
Affiliation(s)
- Ajit G Thomas
- Brain Science Institute, NeuroTranslational Program, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
| | | | | | | | | |
Collapse
|
7
|
Molinaro G, Traficante A, Riozzi B, Di Menna L, Curto M, Pallottino S, Nicoletti F, Bruno V, Battaglia G. Activation of mGlu2/3 Metabotropic Glutamate Receptors Negatively Regulates the Stimulation of Inositol Phospholipid Hydrolysis Mediated by 5-Hydroxytryptamine2A Serotonin Receptors in the Frontal Cortex of Living Mice. Mol Pharmacol 2009; 76:379-87. [DOI: 10.1124/mol.109.056580] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
|
8
|
Matrisciano F, Caruso A, Orlando R, Marchiafava M, Bruno V, Battaglia G, Gruber SHM, Melchiorri D, Tatarelli R, Girardi P, Mathè AA, Nicoletti F. Defective group-II metaboropic glutamate receptors in the hippocampus of spontaneously depressed rats. Neuropharmacology 2008; 55:525-31. [PMID: 18590921 DOI: 10.1016/j.neuropharm.2008.05.014] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Revised: 05/06/2008] [Accepted: 05/18/2008] [Indexed: 12/21/2022]
Abstract
Spontaneously depressed flinders sensitive line (FSL) rats showed a reduced expression of mGlu2/3 metabotropic glutamate receptors in the hippocampus, as compared to "non-depressed" flinders resistant line (FRL) rats. No changes in mGlu2/3 receptor protein levels were found in other brain regions, including the amygdala, hypothalamus, and cerebral cortex. Biochemical analysis of receptor signalling supported the reduction of mGlu2/3 receptors in the hippocampus of FSL rats. Accordingly, the selective mGlu2/3 receptor agonist, LY379268 (1microM) reduced forskolin-stimulated cAMP formation by 56% and 32% in hippocampal slices from FRL and FSL rats, respectively. In addition, LY379268 enhanced 3,5-dihydroxyphenylglycine-stimulated inositol phospholipid hydrolysis from 65% to 215% in hippocampal slices from FRL rats, whereas it was inactive in slices from FRL rats. We also examined the behavioural response of FSL rats to systemic injection of LY379268 (0.5mg/kg, i.p., once a day for 1-21 days) by measuring the immobility time in the forced swim test, which is known to be increased in these rats. LY379268 was administered alone or combined with the classical antidepressant, chlorimipramine (10mg/kg, i.p.). LY379268 alone had no effect at any of the selected time-points, whereas chlorimipramine alone reduced the immobility time only after 21 days of treatment. In contrast, when combined with LY379268, chlorimipramine reduced the immobility time during the first 14 days of treatment. These data support the view that mGlu2/3 receptors might be involved in the pathophysiology of depressive disorders, and that pharmacological activation of these receptors may shorten the latency of antidepressant medication.
Collapse
Affiliation(s)
- F Matrisciano
- Department of Physiology and Pharmacology, University of Rome "Sapienza", Piazzale Aldo Moro, 5, 00185 Rome, Italy.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Zuena AR, Mairesse J, Casolini P, Cinque C, Alemà GS, Morley-Fletcher S, Chiodi V, Spagnoli LG, Gradini R, Catalani A, Nicoletti F, Maccari S. Prenatal restraint stress generates two distinct behavioral and neurochemical profiles in male and female rats. PLoS One 2008; 3:e2170. [PMID: 18478112 PMCID: PMC2366064 DOI: 10.1371/journal.pone.0002170] [Citation(s) in RCA: 265] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2008] [Accepted: 04/01/2008] [Indexed: 12/21/2022] Open
Abstract
Prenatal Restraint Stress (PRS) in rats is a validated model of early stress resulting in permanent behavioral and neurobiological outcomes. Although sexual dimorphism in the effects of PRS has been hypothesized for more than 30 years, few studies in this long period have directly addressed the issue. Our group has uncovered a pronounced gender difference in the effects of PRS (stress delivered to the mothers 3 times per day during the last 10 days of pregnancy) on anxiety, spatial learning, and a series of neurobiological parameters classically associated with hippocampus-dependent behaviors. Adult male rats subjected to PRS (“PRS rats”) showed increased anxiety-like behavior in the elevated plus maze (EPM), a reduction in the survival of newborn cells in the dentate gyrus, a reduction in the activity of mGlu1/5 metabotropic glutamate receptors in the ventral hippocampus, and an increase in the levels of brain-derived neurotrophic factor (BDNF) and pro-BDNF in the hippocampus. In contrast, female PRS rats displayed reduced anxiety in the EPM, improved learning in the Morris water maze, an increase in the activity of mGlu1/5 receptors in the ventral and dorsal hippocampus, and no changes in hippocampal neurogenesis or BDNF levels. The direction of the changes in neurogenesis, BDNF levels and mGlu receptor function in PRS animals was not consistent with the behavioral changes, suggesting that PRS perturbs the interdependency of these particular parameters and their relation to hippocampus-dependent behavior. Our data suggest that the epigenetic changes in hippocampal neuroplasticity induced by early environmental challenges are critically sex-dependent and that the behavioral outcome may diverge in males and females.
Collapse
Affiliation(s)
- Anna Rita Zuena
- Perinatal Stress Lab., University Lille 1, Villeneuve d'Ascq, France
- Department of Human Physiology and Pharmacology, University of Rome “La Sapienza”, Rome, Italy
| | - Jerome Mairesse
- Perinatal Stress Lab., University Lille 1, Villeneuve d'Ascq, France
- Department of Human Physiology and Pharmacology, University of Rome “La Sapienza”, Rome, Italy
| | - Paola Casolini
- Department of Human Physiology and Pharmacology, University of Rome “La Sapienza”, Rome, Italy
| | - Carlo Cinque
- Department of Human Physiology and Pharmacology, University of Rome “La Sapienza”, Rome, Italy
| | | | | | - Valentina Chiodi
- Department of Human Physiology and Pharmacology, University of Rome “La Sapienza”, Rome, Italy
| | | | - Roberto Gradini
- Istituto Neurologico Mediterraneo Neuromed, Pozzilli, Italy
- Department of Experimental Medicine, University of Rome “La Sapienza”, Rome, Italy
| | - Assia Catalani
- Department of Human Physiology and Pharmacology, University of Rome “La Sapienza”, Rome, Italy
| | - Ferdinando Nicoletti
- Department of Human Physiology and Pharmacology, University of Rome “La Sapienza”, Rome, Italy
- Istituto Neurologico Mediterraneo Neuromed, Pozzilli, Italy
| | - Stefania Maccari
- Perinatal Stress Lab., University Lille 1, Villeneuve d'Ascq, France
- Department of Human Physiology and Pharmacology, University of Rome “La Sapienza”, Rome, Italy
- * E-mail:
| |
Collapse
|
10
|
Brackmann F, de Meijere A. Natural Occurrence, Syntheses, and Applications of Cyclopropyl-Group-Containing α-Amino Acids. 2. 3,4- and 4,5-Methanoamino Acids. Chem Rev 2007; 107:4538-83. [DOI: 10.1021/cr0784083] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Farina Brackmann
- Institut für Organische und Biomolekulare Chemie der Georg-August-Universität Göttingen, Tammannstrasse 2, D-37077 Göttingen, Germany
| | - Armin de Meijere
- Institut für Organische und Biomolekulare Chemie der Georg-August-Universität Göttingen, Tammannstrasse 2, D-37077 Göttingen, Germany
| |
Collapse
|
11
|
Franco R, Lluis C, Canela EI, Mallol J, Agnati L, Casadó V, Ciruela F, Ferré S, Fuxe K. Receptor-receptor interactions involving adenosine A1 or dopamine D1 receptors and accessory proteins. J Neural Transm (Vienna) 2006; 114:93-104. [PMID: 17024327 DOI: 10.1007/s00702-006-0566-7] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2006] [Accepted: 07/13/2006] [Indexed: 11/24/2022]
Abstract
The molecular basis for the known intramembrane receptor-receptor interactions among heptahelical receptors (G protein coupled receptors, GPCR) was postulated to be heteromerization based on receptor subtype specific interactions between different types of homomers of GPCR. Adenosine and dopamine receptors in the basal ganglia have been fundamental to demonstrate the existence of receptor heteromers and the functional consequences of such molecular interactions. The heterodimer is only one type of heteromeric complex and the evidence is equally compatible with the existence of higher order heteromeric complexes, where also adapter proteins such as homer proteins and scaffolding proteins can exist, assisting in the process of linking the GPCR and ion channel receptors together in a receptor mosaic that may have special integrative value and may constitute the molecular basis for learning and memory. Heteromerization of D(2) dopamine and A(2A) adenosine receptors is reviewed by Fuxe in another article in this special issue. Here, heteromerization between D(1) dopamine and A(1) adenosine receptors is reviewed. Heteromers formed by dopamine D(1) and D(2) receptors and by adenosine A(1) and A(2A) receptors also occur in striatal cells and open new perspectives to understand why two receptors with apparently opposite effects are expressed in the same neuron and in the nerve terminals. The role of accessory proteins also capable of interacting with receptor-receptor heteromers in regulating the traffic and the molecular physiology of these receptors is also discussed. Overall, the knowledge of the reason why such complex networks of receptor-receptor and receptor-protein interactions occur in striatal cells is crucial to develop new strategies to combat neurological and neuropsychiatric diseases.
Collapse
Affiliation(s)
- R Franco
- Molecular Neurobiology Unit, Department of Biochemistry and Molecular Biology, IDIBAPS (Institut d'Investigacions Biomèdiques August Pi i Sunyer), Universitat de Barcelona, Barcelona, Spain.
| | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Calò L, Bruno V, Spinsanti P, Molinari G, Korkhov V, Esposito Z, Patanè M, Melchiorri D, Freissmuth M, Nicoletti F. Interactions between ephrin-B and metabotropic glutamate 1 receptors in brain tissue and cultured neurons. J Neurosci 2006; 25:2245-54. [PMID: 15745950 PMCID: PMC6726088 DOI: 10.1523/jneurosci.4956-04.2005] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We examined the interaction between ephrins and metabotropic glutamate (mGlu) receptors in the developing brain and cultured neurons. EphrinB2 coimmunoprecipitated with mGlu1a receptors, in all of the brain regions examined, and with mGlu5 receptors in the corpus striatum. In striatal slices, activation of ephrinB2 by a clustered form of its target receptor, EphB1, amplified the mGlu receptor-mediated stimulation of polyphosphoinositide (PI) hydrolysis. This effect was abolished in slices treated with mGlu1 or NMDA receptor antagonists but was not affected by pharmacological blockade of mGlu5 receptors. An interaction among ephrinB2, mGlu1 receptor, and NMDA was supported by the following observations: (1) the NR1 subunit of NMDA receptors coimmunoprecipitated with mGlu1a receptors and ephrinB2 in striatal lysates; (2) clustered EphB1 amplified excitatory amino acid-stimulated PI hydrolysis in cultured granule cells grown under conditions that favored the expression of mGlu1a receptors; and (3) clustered EphB1 amplified the enhancing effect of mGlu receptor agonists on NMDA toxicity in cortical cultures, and its action was sensitive to mGlu1 receptor antagonists. Finally, fluorescence resonance energy transfer and coclustering analysis in human embryonic kidney 293 cells excluded a physical interaction between ephrinB2 and mGlu1a (or mGlu5 receptors). A functional interaction between ephrinB and mGlu1 receptors, which likely involves adaptor or scaffolding proteins, might have an important role in the regulation of developmental plasticity.
Collapse
MESH Headings
- Analysis of Variance
- Animals
- Animals, Newborn
- Astrocytes/drug effects
- Astrocytes/metabolism
- Blotting, Western/methods
- Brain/cytology
- Brain/growth & development
- Brain/metabolism
- Carrier Proteins/metabolism
- Cells, Cultured
- Coculture Techniques/methods
- Dose-Response Relationship, Drug
- Drug Interactions
- Embryo, Mammalian
- Enzyme Activation/drug effects
- Excitatory Amino Acid Agonists/pharmacology
- Excitatory Amino Acid Antagonists/pharmacology
- Fluorescence Resonance Energy Transfer/methods
- Glial Fibrillary Acidic Protein/metabolism
- Homer Scaffolding Proteins
- Humans
- Hydrolysis/drug effects
- Immunoprecipitation/methods
- Luminescent Proteins/metabolism
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Neurons/drug effects
- Neurons/physiology
- Peptide Fragments/pharmacology
- Phosphatidylinositol Phosphates/metabolism
- Potassium/pharmacology
- Protein Structure, Tertiary/physiology
- Quisqualic Acid/pharmacology
- RGS Proteins
- Rats
- Rats, Sprague-Dawley
- Receptor, Metabotropic Glutamate 5
- Receptors, Dopamine D1/metabolism
- Receptors, Eph Family/chemistry
- Receptors, Eph Family/metabolism
- Receptors, Metabotropic Glutamate/deficiency
- Receptors, Metabotropic Glutamate/metabolism
- Repressor Proteins/metabolism
- Spectrometry, Fluorescence/methods
- Time Factors
- Transfection/methods
- Tritium/metabolism
Collapse
Affiliation(s)
- L Calò
- Department of Human Physiology and Pharmacology, University of Rome La Sapienza, 00185 Rome, Italy
| | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Franco R, Ciruela F, Casadó V, Cortes A, Canela EI, Mallol J, Agnati LF, Ferré S, Fuxe K, Lluis C. Partners for adenosine A1 receptors. J Mol Neurosci 2005; 26:221-32. [PMID: 16012195 DOI: 10.1385/jmn:26:2-3:221] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
G protein-coupled receptors (GPCRs) are targets for therapy in a variety of neurological diseases. Using adenosine A1 receptors (A1Rs) as paradigm of GPCRs, this review focuses on how protein-protein interactions, from monomers to heteromers, can contribute to hormone/neurotransmitter/neuromodulator regulation. The interaction of A1Rs with other membrane receptors, enzymes, and adaptor and scaffolding proteins is relevant for receptor traffic, internalization, and desensitization, and A1Rs are extremely important in driving signaling through different intracellular pathways. There is even the possibility of linking together GPCR heteromeric complexes with ion channel receptors in a receptor mosaic that might have special integrative value and might constitute the molecular basis for learning and memory.
Collapse
Affiliation(s)
- Rafael Franco
- Department of Biochemistry and Molecular Biology, University of Barcelona, Barcelona, Spain.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Casolini P, Zuena AR, Cinque C, Matteucci P, Alemà GS, Adriani W, Carpinelli G, Santoro F, Alleva E, Bosco P, Nicoletti F, Laviola G, Catalani A. Sub-neurotoxic neonatal anoxia induces subtle behavioural changes and specific abnormalities in brain group-I metabotropic glutamate receptors in rats. J Neurochem 2005; 95:137-45. [PMID: 16181418 DOI: 10.1111/j.1471-4159.2005.03349.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Anoxia in the first week of life can induce neuronal death in vulnerable brain regions usually associated with an impairment of cognitive function that can be detected later in life. We set-up a model of subneurotoxic anoxia based on repeated exposures to 100% nitrogen during the first 7 days of post-natal life. This mild post-natal exposure to anoxia specifically modified the behaviour of the male adult rats, which showed an attention deficit and an increase in anxiety, without any impairment in spatial learning and any detectable brain damage (magnetic resonance imaging and histological analysis). Post-anoxic rats showed a reduction in the expression of group-I metabotropic glutamate receptors (i.e. mGlu1 and mGlu5 receptors) in the hippocampus and cerebral cortex, whereas expression of the mGlu 2/3 receptors, the NR1 subunit of NMDA receptors, and the GluR1 subunit of alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptors was unchanged. mGlu1 and mGlu5 receptor signalling was also impaired in postanoxic rats, as revealed by a reduced efficacy of the agonist (1S,3R)-1-Aminocyclopentane-1,3-dicarboxylic acid (1S,3R-ACPD) to stimulate polyphosphoinositide hydrolysis in hippocampal slices. We conclude that rats subjected to subneurotoxic doses of anoxia during the early post-natal life develop behavioural symptoms that are frequently encountered in the inattentive subtype of the attention deficit hyperactivity disorder, and that group-I mGlu receptors may be involved in the pathophysiology of these symptoms.
Collapse
Affiliation(s)
- P Casolini
- Department of Human Physiology and Pharmacology, University of Rome La Sapienza, Faculty of Medicine, Rome, Italy.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Matrisciano F, Scaccianoce S, Del Bianco P, Panaccione I, Canudas AM, Battaglia G, Riozzi B, Ngomba RT, Molinaro G, Tatarelli R, Melchiorri D, Nicoletti F. Metabotropic glutamate receptors and neuroadaptation to antidepressants: imipramine-induced down-regulation of beta-adrenergic receptors in mice treated with metabotropic glutamate 2/3 receptor ligands. J Neurochem 2005; 93:1345-52. [PMID: 15934953 DOI: 10.1111/j.1471-4159.2005.03141.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Antidepressant drugs have a clinical latency that correlates with the development of neuroadaptive changes, including down-regulation of beta-adrenergic receptors in different brain regions. The identification of drugs that shorten this latency will have a great impact on the treatment of major depressive disorders. We report that the time required for the antidepressant imipramine to reduce the expression of beta-adrenergic receptors in the hippocampus is reduced by a co-administration with centrally active ligands of type 2/3 metabotropic glutamate (mGlu2/3) receptors. Daily treatment of mice with imipramine alone (10 mg/kg, i.p.) reduced the expression of beta-adrenergic receptors in the hippocampus after 21 days, but not at shorter times, as assessed by western blot analysis of beta1-adrenergic receptors and by the amount of specifically bound [3H]CGP-12177, a selective beta-adrenergic receptor ligand. Down-regulation of beta-adrenergic receptors occurred at shorter times (i.e. after 14 days) when imipramine was combined with low doses (0.5 mg/kg, i.p.) of the selective mGlu2/3 receptor agonist LY379268, or with the preferential mGlu2/3 receptor antagonist LY341495 (1 mg/kg, i.p.). Higher doses of LY379268 (2 mg/kg, i.p.) were inactive. This intriguing finding suggests that neuroadaptation to imipramine--at least as assessed by changes in the expression of beta1-adrenergic receptors--is influenced by drugs that interact with mGlu2/3 receptors and stimulates further research aimed at establishing whether any of these drugs can shorten the clinical latency of classical antidepressants.
Collapse
MESH Headings
- Adaptation, Physiological
- Amino Acids/pharmacology
- Animals
- Antidepressive Agents, Tricyclic/pharmacology
- Bridged Bicyclo Compounds, Heterocyclic/pharmacology
- Down-Regulation
- Excitatory Amino Acid Antagonists/pharmacology
- Hippocampus/metabolism
- Imipramine/pharmacology
- Ligands
- Male
- Mice
- Mice, Inbred Strains
- Nervous System Physiological Phenomena
- Reaction Time/drug effects
- Receptors, Adrenergic, beta/metabolism
- Receptors, Metabotropic Glutamate/administration & dosage
- Receptors, Metabotropic Glutamate/agonists
- Receptors, Metabotropic Glutamate/antagonists & inhibitors
- Receptors, Metabotropic Glutamate/metabolism
- Xanthenes/pharmacology
Collapse
Affiliation(s)
- F Matrisciano
- Department of Human Physiology and Pharmacology, University of Rome La Sapienza, Rome, Italy
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Cinque C, Zuena AR, Casolini P, Ngomba RT, Melchiorri D, Maccari S, Nicoletti F, Di Giorgi Gerevini V, Catalani A. Reduced activity of hippocampal group-I metabotropic glutamate receptors in learning-prone rats. Neuroscience 2004; 122:277-84. [PMID: 14596868 DOI: 10.1016/s0306-4522(03)00442-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Following the hypothesis of the "signal-to-noise" ratio we examined whether changes in the activity of group-I metabotropic glutamate (mGlu) receptors in the hippocampus are associated with a condition that specifically enhances the learning capacity in rats. As a model, we used rats that had been nursed by mothers drinking a solution of corticosterone (13.5 mg of daily intake of corticosterone hemisuccinate) during the lactation period. These rats were prone to learn, as indicated by a better performance in a passive avoidance test. Stimulation of polyphosphoinositide (PI) hydrolysis by the mGlu receptor agonist, 1S,3R-1-amino-cyclopentan-1,3-dicarboxylic acid (1S,3R-ACPD), was attenuated in hippocampal slices prepared from corticosterone-nursed male and female rats at 30 or 60 days of postnatal life, an age at which an increased learning capacity could be demonstrated. This effect was specific because the PI response to carbamylcholine was unchanged. A reduced PI hydrolysis in corticosterone-nursed rats was also observed when group-I mGlu receptors (i.e. mGlu1 and -5 receptors) were selectively activated using 3,5-dihydroxyphenylglycine or 1S,3R-APCD combined with the selective group-II mGlu receptor antagonist, 2S-2-amino-2-(1S,2S-2-carboxycyclopropan-1-yl)-3-(xanth-9-yl)propionate. Western blot analysis showed a selective reduction in the expression of mGlu1a receptor protein in the hippocampus of corticosterone-nursed rats, whereas expression of mGlu5 and mGlu2/3 receptors was unchanged. The reduction in mGlu-receptor mediated PI hydrolysis in the hippocampus may contribute to the greater learning capacity of corticosterone-nursed rats by reducing the background noise over which a specific signal must be superimposed during learning. This hypothesis was supported by the evidence that mGlu-receptor stimulated PI hydrolysis was amplified in hippocampal slices from rats subjected to a passive avoidance learning paradigm, and that this amplification was greater in slices from corticosterone-nursed rats of both sexes.
Collapse
Affiliation(s)
- C Cinque
- Department of Human Physiology and Pharmacology, University of Rome La Sapienza, Faculty of Medicine, P.le A. Moro 5, I-00185, Rome, Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Werry TD, Wilkinson GF, Willars GB. Mechanisms of cross-talk between G-protein-coupled receptors resulting in enhanced release of intracellular Ca2+. Biochem J 2003; 374:281-96. [PMID: 12790797 PMCID: PMC1223610 DOI: 10.1042/bj20030312] [Citation(s) in RCA: 145] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2003] [Revised: 06/03/2003] [Accepted: 06/05/2003] [Indexed: 12/21/2022]
Abstract
Alteration in [Ca(2+)](i) (the intracellular concentration of Ca(2+)) is a key regulator of many cellular processes. To allow precise regulation of [Ca(2+)](i) and a diversity of signalling by this ion, cells possess many mechanisms by which they are able to control [Ca(2+)](i) both globally and at the subcellular level. Among these are many members of the superfamily of GPCRs (G-protein-coupled receptors), which are characterized by the presence of seven transmembrane domains. Typically, those receptors able to activate PLC (phospholipase C) enzymes cause release of Ca(2+) from intracellular stores and influence Ca(2+) entry across the plasma membrane. It has been well documented that Ca(2+) signalling by one type of GPCR can be influenced by stimulation of a different type of GPCR. Indeed, many studies have demonstrated heterologous desensitization between two different PLC-coupled GPCRs. This is not surprising, given our current understanding of negative-feedback regulation and the likely shared components of the signalling pathway. However, there are also many documented examples of interactions between GPCRs, often coupling preferentially to different signalling pathways, which result in a potentiation of Ca(2+) signalling. Such interactions have important implications for both the control of cell function and the interpretation of in vitro cell-based assays. However, there is currently no single mechanism that adequately accounts for all examples of this type of cross-talk. Indeed, many studies either have not addressed this issue or have been unable to determine the mechanism(s) involved. This review seeks to explore a range of possible mechanisms to convey their potential diversity and to provide a basis for further experimental investigation.
Collapse
Affiliation(s)
- Tim D Werry
- Department of Cell Physiology and Pharmacology, Medical Sciences Building, University of Leicester, UK
| | | | | |
Collapse
|
18
|
Matrisciano F, Storto M, Ngomba RT, Cappuccio I, Caricasole A, Scaccianoce S, Riozzi B, Melchiorri D, Nicoletti F. Imipramine treatment up-regulates the expression and function of mGlu2/3 metabotropic glutamate receptors in the rat hippocampus. Neuropharmacology 2002; 42:1008-15. [PMID: 12128001 DOI: 10.1016/s0028-3908(02)00057-6] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We examined the effect of a chronic imipramine treatment (10 mg/kg, i.p., once daily for 21 days) on the expression and function of metabotropic glutamate (mGlu) receptors in discrete regions of the rat brain. Chronic imipiramine treatment up-regulated the expression of mGlu2/3 receptor proteins in the hippocampus, nucleus accumbens, cerebral cortex and corpus striatum. Expression of mGlu1a receptor protein was increased exclusively in the hippocampus, whereas no changes in the expression of mGlu4 and mGlu5 receptors or Homer-1a protein were detected. Using hippocampal slices, we examined the stimulation of polyphosphoinositide (PI) hydrolysis induced by mGlu receptor agonists in control and imipramine-treated rats. Imipramine treatment amplified the PI response to the non subtype-selective mGlu receptor agonist, 1S,3R-aminocyclopentane-1,3-dicarboxylated (1S,3R-ACPD) in both hippocampal and cortical slices, but failed to affect the response to the selective mGlu1/5 receptor agonist, S-3,5-dihydroxyphenylglycine (DHPG). Amplification was restored when DHPG was combined with the selective mGlu2/3 receptor agonist, LY379268. In addition, 1S,3R-ACPD-stimulated PI hydrolysis was no longer enhanced in imipramine-treated rats when the mGlu2/3 component of the PI response was abrogated by the antagonist, LY341495. In contrast, the ability of LY379268 to inhibit forskolin-stimulated cAMP formation was reduced in hippocampal slices of rats chronically treated with imipramine. Taken together, these results suggest that neuroadaptive changes in the expression and function of mGlu2/3 receptors occur in response to chronic antidepressants.
Collapse
Affiliation(s)
- F Matrisciano
- Department of Human Physiology and Pharmacology, University of Rome La Sapienza, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Ciruela F, Escriche M, Burgueno J, Angulo E, Casado V, Soloviev MM, Canela EI, Mallol J, Chan WY, Lluis C, McIlhinney RA, Franco R. Metabotropic glutamate 1alpha and adenosine A1 receptors assemble into functionally interacting complexes. J Biol Chem 2001; 276:18345-51. [PMID: 11278325 DOI: 10.1074/jbc.m006960200] [Citation(s) in RCA: 149] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Recently, evidence has emerged that seven transmembrane G protein-coupled receptors may be present as homo- and heteromers in the plasma membrane. Here we describe a new molecular and functional interaction between two functionally unrelated types of G protein-coupled receptors, namely the metabotropic glutamate type 1alpha (mGlu(1alpha) receptor) and the adenosine A1 receptors in cerebellum, primary cortical neurons, and heterologous transfected cells. Co-immunoprecipitation experiments showed a close and subtype-specific interaction between mGlu(1alpha) and A1 receptors in both rat cerebellar synaptosomes and co-transfected HEK-293 cells. By using transiently transfected HEK-293 cells a synergy between mGlu(1alpha) and A1 receptors in receptor-evoked [Ca(2+)](i) signaling has been shown. In primary cultures of cortical neurons we observed a high degree of co-localization of the two receptors, and excitotoxicity experiments in these cultures also indicate that mGlu(1alpha) and A1 receptors are functionally related. Our results provide a molecular basis for adenosine/glutamate receptors cross-talk and open new perspectives for the development of novel agents to treat neuropsychiatric disorders in which abnormal glutamatergic neurotransmission is involved.
Collapse
Affiliation(s)
- F Ciruela
- Department of Biochemistry, University of Barcelona, 08028 Barcelona, Spain
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Ciruela F, Escriche M, Soloviev MM, Canela EI, Burgeño J, Mallol J, Chan WY, Lluis C, McIlhinney RJ, Franco R. Adenosine-glutamate receptor-receptor interactions in the central nervous system. Drug Dev Res 2001. [DOI: 10.1002/ddr.1129] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
|
21
|
Copani A, Romano C, Di Giorgi Gerevini V, Nicosia A, Casabona G, Storto M, Mutel V, Nicoletti F. Reducing conditions differentially affect the functional and structural properties of group-I and -II metabotropic glutamate receptors. Brain Res 2000; 867:165-72. [PMID: 10837810 DOI: 10.1016/s0006-8993(00)02293-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
We have examined the influence of reducing conditions on the activity of group-I or -II metabotropic glutamate receptors. In cultured cerebellar granule cells or in hippocampal slices, the reducing agent dithiothreitol (DTT) inhibited the stimulation of polyphosphoinositide (PPI) hydrolysis elicited by group-I mGlu receptor agonists without affecting responses to norepinephrine or carbamylcholine. Similarly, DTT reduced the increase in intracellular free Ca(2+) induced by glutamate in HEK-293 cells expressing mGlu5 receptors. In adult hippocampal slices, the selective group-II mGlu receptor agonist, (2S,1'R,2'R,3'R)-2-(2, 3-dicarboxycyclopropyl)glycine (DCG-IV) had no effect per se on PPI hydrolysis, but potentiated the response to quisqualate. Although DTT substantially attenuated the action of quisqualate, it did not affect the potentiation by DCG-IV, suggesting that group-II mGlu receptors are resistant to extracellular reduction. Accordingly, DTT did not affect the inhibition of forskolin-stimulated cAMP formation induced by maximally effective concentrations of group-II mGlu receptor agonists in hippocampal slices or in CHO cells expressing mGlu2 receptors. At structural level, DTT differentially affected the aggregation state of mGlu1a, -2/3 or -5 receptors. In immunoblots performed under non-reducing conditions, mGlu1a, -2/3 or -5 antibodies labeled exclusively a high-molecular weight band, corresponding to receptor dimers. Under reducing conditions, mGlu1a or -5 receptors were detected as monomers, whereas a large proportion of mGlu2/3 receptors was still present in a dimeric form. We conclude that reducing conditions differentially influence the aggregation state of group-I and -II mGlu receptors and suggest that dimerization affects the functional activity of native mGlu receptors.
Collapse
Affiliation(s)
- A Copani
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Catania, Viale A. Doria, 6, 95125, Catania, Italy
| | | | | | | | | | | | | | | |
Collapse
|
22
|
Schoepp DD, Jane DE, Monn JA. Pharmacological agents acting at subtypes of metabotropic glutamate receptors. Neuropharmacology 1999; 38:1431-76. [PMID: 10530808 DOI: 10.1016/s0028-3908(99)00092-1] [Citation(s) in RCA: 831] [Impact Index Per Article: 33.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Metabotropic (G-protein-coupled) glutamate (mGlu) receptors have now emerged as a recognized, but still relatively new area of excitatory amino acid research. Current understanding of the roles and involvement of mGlu receptor subtypes in physiological/pathophysiological functions of the central nervous system has been recently propelled by the emergence of various structurally novel, potent, and mGlu receptor selective pharmacological agents. This article reviews the evolution of pharmacological agents that have been reported to target mGlu receptors, with a focus on the known receptor subtype selectivities of current agents.
Collapse
Affiliation(s)
- D D Schoepp
- Lilly Research Laboratories, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN 46285, USA.
| | | | | |
Collapse
|
23
|
Toms NJ, Roberts PJ. Group 1 mGlu receptors elevate [Ca2+]i in rat cultured cortical type 2 astrocytes: [Ca2+]i synergy with adenosine A1 receptors. Neuropharmacology 1999; 38:1511-7. [PMID: 10530813 DOI: 10.1016/s0028-3908(99)00090-8] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Brain macroglia are known to express a diverse array of neurotransmitter receptors whose signal transduction pathways may be subject to heteroreceptor 'cross-talk'. In the current study we have examined group 1 mGlu receptor-evoked [Ca2+]i signalling, and possible heteroreceptor cross-talk, in cultured type 2 astrocytes. The selective group 1 metabotropic glutamate (mGlu) receptor agonist (S)-3,5-dihydroxyphenylglycine (DHPG) elevated [Ca2+]i (EC50 = 1.7 +/- 0.6 microM); an effect reversed by the selective mGlu receptor antagonist (S)-alpha-methyl-4-carboxyphenylglycine (IC50 = 52.7 +/- 8.7 microM). DHPG-evoked [Ca2+]i responses were abolished by (1) thapsigargin (100 nM), implicating the involvement of internal Ca2+ stores in group 1 mGlu [Ca2+]i responses and (2) the removal of extracellular Ca2+. When applied alone, the selective adenosine A1 receptor agonist, N6-cyclopentyladenosine (CPA, 100 nM) failed to influence [Ca2+]i. However, in the presence of 1 microM DHPG, CPA potently (EC50 = 12.3 +/- 1.9 nM) increased [Ca2+]i responses. In the presence of 100 nM CPA, the efficacy of DHPG was doubled without any significant change in the DHPG EC50 value. This effect was reversed by either the selective adenosine A1 receptor antagonist, 8-cyclopentyltheophylline (IC50 = 50.3 +/- 19.9 nM) or overnight incubation with Pertussis toxin (100 ng/ml). We conclude that (1) type 2 astrocytes contain group 1 mGlu receptors coupled to [Ca2+]i signalling and (2) co-activation of adenosine A1 receptors enhances group 1 mGlu-evoked [Ca2+]i responses in these cells via a Gi/o G protein-mediated mechanism.
Collapse
Affiliation(s)
- N J Toms
- Department of Pharmacology, School of Medical Sciences, University of Bristol, UK
| | | |
Collapse
|
24
|
Schröder UH, Opitz T, Jäger T, Sabelhaus CF, Breder J, Reymann KG. Protective effect of group I metabotropic glutamate receptor activation against hypoxic/hypoglycemic injury in rat hippocampal slices: timing and involvement of protein kinase C. Neuropharmacology 1999; 38:209-16. [PMID: 10218861 DOI: 10.1016/s0028-3908(98)00180-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Excessive release of glutamate during ischemia leads to sustained neuronal damage. In this study we investigated the influence of metabotropic glutamate receptor (mGluR) activation on neuronal recovery from a hypoxic/hypoglycemic event in hippocampal slices from rats. The slices were transiently exposed to an oxygen- and glucose-free environment in an interface chamber and the synaptically evoked population spike in the CA1 region was taken as a measure of neuronal viability. Under control conditions the population spike amplitude recovered to 41.4% of baseline value within 1 h after hypoxia/hypoglycemia. The specific mGluR group I agonist 3,5-dihydroxyphenylglycine (DHPG, 10 microM) increased the recovery rate to 88.3% of baseline value when applied from 20 min before until 10 min after the event. Similar recovery rates were obtained when DHPG was present only 10 or 20 min before hypoxia/hypoglycemia (89.3% and 79.3% of baseline value, respectively). However, when applied later, DHPG had no protective effect. Co-application of the protein kinase C (PKC) inhibitors staurosporine (100 nM) or chelerythrine (30 microM) prevented the protective effect of DHPG. Our data suggest that group I mGluR agonists are only protective when present prior to the onset of the hypoxic/hypoglycemic event and that the activation of PKC is a critical step of the protective mechanism.
Collapse
Affiliation(s)
- U H Schröder
- Department of Neurophysiology, Federal Institute for Neurobiology, Magdeburg, Germany.
| | | | | | | | | | | |
Collapse
|
25
|
Huang L, Killbride J, Rowan MJ, Anwyl R. Activation of mGluRII induces LTD via activation of protein kinase A and protein kinase C in the dentate gyrus of the hippocampus in vitro. Neuropharmacology 1999; 38:73-83. [PMID: 10193900 DOI: 10.1016/s0028-3908(98)00168-3] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The involvement of metabotropic glutamate receptor group II (mGluRII) in the induction of long-term depression (LTD) was investigated in the medial perforant path of the rat dentate gyrus, a region with a very high density of mGluRII. Perfusion of either of two potent mGluRII agonists, (2S,1R,2R,3R)-2-(2S, 1'R, 2'R, 3'R)-2 (2' 3'-dicarboxycyclopropyl)glycine (DCG-IV) or (+)-2- aminobicyclo[3.1.0]hexane-2-6-dicarboxylic acid (LY354740) induced a reversible inhibition of the field EPSP followed, upon washout of the agonist, by LTD. The reversible inhibition was associated with a change in paired pulse depression, indicating an underlying presynaptic reduction in the probability of transmitter release, whereas the LTD was not associated with a change in paired pulse depression, indicating either a presynaptic reduction in the number of active release sites, or a postsynaptic change. Further evidence that the DCG-IV-induced LTD was generated by activation of mGluRII was the finding that the mGluRII antagonist (RS)-alpha-methylserine-O-phosphate monophenylphosphoryl ester (MSOPPE) prevented the induction of the LTD induced by DCG-IV. The DCG-IV-induced LTD showed mutual occlusion with LFS-induced LTD. The generation of the agonist-induced LTD required, in part, activation of N-methyl-D-aspartate receptors (NMDAR), as LTD induction was partially blocked in the presence of the NMDAR antagonist D-2-amino-5-phosphonopentanoate (AP5). Evidence for involvement of protein kinase C (PKC) and protein kinase (PKA) in the induction of LTD by activation of mGluRII was obtained by showing an inhibition of the DCG-IV-induced LTD by the PKC inhibitors Ro-31-8220 and bisindolylmaleimide I, and also by the PKA inhibitor H-89. The study demonstrates that activation of mGluRII induces LTD via activation the PKA and PKC pathways in the medial perforant path of the dentate gyrus.
Collapse
Affiliation(s)
- L Huang
- Department of Physiology, Pharmacology and Therapeutics, Trinity College, Dublin, Ireland
| | | | | | | |
Collapse
|
26
|
Neuroprotection by glial metabotropic glutamate receptors is mediated by transforming growth factor-beta. J Neurosci 1998. [PMID: 9822720 DOI: 10.1523/jneurosci.18-23-09594.1998] [Citation(s) in RCA: 209] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The medium collected from cultured astrocytes transiently exposed to the group-II metabotropic glutamate (mGlu) receptor agonists (2S,1'R, 2'R,3'R)-2-(2,3-dicarboxycyclopropyl)glycine (DCG-IV) or (S)-4-carboxy-3-hydroxyphenylglycine (4C3HPG) is neuroprotective when transferred to mixed cortical cultures challenged with NMDA (). The following data indicate that this particular form of neuroprotection is mediated by transforming growth factor-beta (TGFbeta). (1) TGFbeta1 and -beta2 were highly neuroprotective against NMDA toxicity, and their action was less than additive with that produced by the medium collected from astrocytes treated with DCG-IV or 4C3HPG (GM/DCG-IV or GM/4C3HPG); (2) antibodies that specifically neutralized the actions of TGFbeta1 or -beta2 prevented the neuroprotective activity of DCG-IV or 4C3HPG, as well as the activity of GM/DCG-IV or GM/4C3HPG; and (3) a transient exposure of cultured astrocytes to either DCG-IV or 4C3HPG led to a delayed increase in both intracellular and extracellular levels of TGFbeta. We therefore conclude that a transient activation of group-II mGlu receptors (presumably mGlu3 receptors) in astrocytes leads to an increased formation and release of TGFbeta, which in turn protects neighbor neurons against excitotoxic death. These results offer a new strategy for increasing the local production of neuroprotective factors in the CNS.
Collapse
|
27
|
Nouranifar R, Blitzer RD, Wong T, Landau E. Metabotropic glutamate receptors limit adenylyl cyclase-mediated effects in rat hippocampus via protein kinase C. Neurosci Lett 1998; 244:101-5. [PMID: 9572595 DOI: 10.1016/s0304-3940(98)00131-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Glutamate receptors of the metabotropic type (mGluRs) activate protein kinase C in hippocampus, but few physiological functions of this pathway are known. The present data show that mGluRs utilize protein kinase C to inhibit another second messenger system, the adenylyl cyclase pathway, in neurons of the CA1 area of hippocampus. Activation of mGluRs prevented beta-adrenergic receptors, which couple to adenylyl cyclase, from blocking the slow Ca2+-dependent afterhyperpolarization (AHP). Since the afterhyperpolarization modulates neuronal responsiveness, crosstalk between protein kinase C and the adenylyl cyclase pathway is likely to have physiological consequences. Moreover, mGluRs themselves block the afterhyperpolarization, so the observed interference with the beta-adrenergic response constitutes a hierarchical relationship in which mGluRs are dominant over beta-adrenergic receptors.
Collapse
Affiliation(s)
- R Nouranifar
- Psychiatry Service, Bronx Veterans Administration Medical Center, NY 10468, USA
| | | | | | | |
Collapse
|
28
|
Mistry R, Golding N, Challiss RA. Regulation of phosphoinositide turnover in neonatal rat cerebral cortex by group I- and II- selective metabotropic glutamate receptor agonists. Br J Pharmacol 1998; 123:581-9. [PMID: 9504400 PMCID: PMC1565187 DOI: 10.1038/sj.bjp.0701626] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
1. The interactive effects of different metabotropic glutamate (mGlu) receptor subtypes to regulate phosphoinositide turnover have been studied in neonatal rat cerebral cortex and hippocampus by use of agonists and antagonists selective between group I and II mGlu receptors. 2, The group II-selective agonist 2R,4R-4-aminopyrrolidine-2,4-dicarboxylate (2R,4R-APDC; 100 microM) had no effect on basal total inositol phosphate ([3H]-InsPx) accumulation (in the presence of Li+) in myo-[3H]-inositol pre-labelled slices, but enhanced the maximal [3H]-InsPx response to the group I-selective agonist (S)-3,5-dihydroxyphenylglycine (DHPG) by about 100% in both hippocampus and cerebral cortex. In cerebral cortex the enhancing effect of 2R,4R-APDC occurred with respect to the maximal responsiveness and had no effect on EC50 values for DHPG (-log EC50 (M): control, 5.56+/-0.05; +2R,4R-APDC, 5.51+/-0.08). 2R,4R-APDC also caused a significant enhancement of the DHPG-stimulated inositol 1,4,5-trisphosphate (Ins(1,4,5)P3) mass response over an initial 0-300 s time-course. 3. The enhancing effects of 2R,4R-APDC on DHPG-stimulated [3H]-InsPx accumulation were observed in both the presence and nominal absence of extracellular Ca2+, and irrespective of whether 2R,4R-APDC was added before, simultaneous with, or subsequent to DHPG. Furthermore, increasing the tissue cyclic AMP concentration up to 100 fold had no effect on DHPG-stimulated Ins(l,4,5)P3 accumulation in the absence or presence of 2R,4R-APDC. 4. 2R,4R-APDC and (2S, 1'R, 2'R, 3'R)-2-(2,3-dicarboxylcyclopropyl)glycine (DCG-IV), the latter agent in the presence of MK-801 to prevent activation of NMDA-receptors, each inhibited forskolin-stimulated cyclic AMP accumulation by about 50%, with respective EC50 values of 1.3 and 0.04 microM (-log EC 50 (M): 2R,4R-APDC, 5.87+/-0.09; DCG-IV, 7.38+/-0.05). In the presence of DHPG (30 microM), 2R,4R-APDC and DCG-IV also concentration-dependently increased [3H]-InsPx accumulation with respective EC50 values of 4.7 and 0.28 microM (-log EC50 (M): 2R,4R-APDC, 5.33+/-0.04; DCG-IV, 6.55+/-0.09) which were 3-7 fold rightward-shifted relative to the adenylyl cyclase inhibitory responses. 5. The group II-selective mGlu receptor antagonist LY307452 (30 microM) caused parallel rightward shifts in the concentration-effect curves for inhibition of forskolin-stimulated adenylyl cyclase, and enhancement of DHPG-stimulated [3H]-InsPx accumulation, by 2R,4R-APDC yielding similar equilibrium dissociation constants (KdS, 3.7+/-1.1 and 4.1+/-0.4 microM respectively) for each response. 6. The ability of 2R,4R-APDC to enhance receptor-mediated [3H]-InsPx accumulation appeared to be agonist-specific; thus although DHPG (100 microM) and the muscarinic cholinoceptor agonist carbachol (10 microM) stimulated similar [3H]-InsPx accumulations, only the response to the former agonist was enhanced by co-activation of group II mGlu receptors. 7. These data demonstrate that second messenger-generating phosphoinositide responses stimulated by group I mGlu receptors are positively modulated by co-activation of group II mGlu receptors in cerebral cortex and hippocampus. The data presented here are discussed with respect to the possible mechanisms which might mediate the modulatory activity, and the physiological and pathophysiological significance of such crosstalk between mGlu receptors.
Collapse
Affiliation(s)
- R Mistry
- Department of Cell Physiology and Pharmacology, University of Leicester
| | | | | |
Collapse
|
29
|
Schaffhauser H, de Barry J, Muller H, Heitz MP, Gombos G, Mutel V. Involvement of a cyclic-AMP pathway in group I metabotropic glutamate receptor responses in neonatal rat cortex. Eur J Pharmacol 1997; 334:289-97. [PMID: 9369360 DOI: 10.1016/s0014-2999(97)01192-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
3,5-Dihydroxyphenylglycine (DHPG), (S)-3-hydroxyphenylglycine and (S)-4-carboxy-3-hydroxyphenylglycine (S-4C3HPG) stimulated phosphoinositide hydrolysis in neonatal rat cortical slices, but with lower maximal effect, in comparison with 2S,1'S,2'S-2-(2'-carboxycyclopropyl)glycine (L-CCG I) or (1S,3R)-1-aminocyclo-pentane-1,3-dicarboxylic acid (1S,3R-ACPD). DHPG, 1S,3R-ACPD, and S-4C3HPG also evoked a rapidly desensitizing increase in [Ca2+]i in cortical layers of neonatal brain slices. (R,S)-alpha-methyl-4-tetrazolyl-phenylglycine (MTPG), and (R,S)-alpha-methyl-4-phosphono-phenylglycine (MPPG) inhibited the increase of phosphoinositide hydrolysis elicited by 1S,3R-ACPD but not that by R,S-DHPG. In contrast, the selective group II receptor agonist (1S,2S,5R,6S)-2-amino-bicyclo-[3.1.0]-hexane-2,6-dicarboxylate (LY 354740) potentiated the response of R,S-DHPG. Finally, 8-(4-chlorophenylthio)-cAMP, a membrane permeant analogue of cAMP, reversed the stimulatory effect of 1S,3R-ACPD and S-4C3HPG on phosphoinositide hydrolysis and [Ca2+]i mobilization, without affecting the response induced by R,S-DHPG. These data suggest that, in neonatal rat cortex, the activation of group II metabotropic glutamate receptors potentiates the phosphoinositide hydrolysis and [Ca2+]i responses mediated by group I metabotropic glutamate receptors.
Collapse
Affiliation(s)
- H Schaffhauser
- Pharma Division Preclinical CNS Research, F. Hoffmann-La Roche Ltd., Basel, Switzerland
| | | | | | | | | | | |
Collapse
|
30
|
Klein J, Iovino M, Vakil M, Shinozaki H, Löffelholz K. Ontogenetic and pharmacological studies on metabotropic glutamate receptors coupled to phospholipase D activation. Neuropharmacology 1997; 36:305-11. [PMID: 9175608 DOI: 10.1016/s0028-3908(97)00024-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The present study was aimed at characterizing the metabotropic receptor subtype which is involved in the activation of phospholipase D (PLD) by glutamate in rat hippocampal slices. We first observed that the ontogenetic profile of glutamate-induced hydrolysis of phosphoinositides and of phosphatidylcholine was strikingly similar. Both pathways were significantly activated by glutamate in tissue taken from 3-, 8- and 15-day old rats, but not in adult rats. PLD activation was strongest in slices taken from 8-day old rats. At this age, quisqualate had a higher potency for PLD activation (EC50: 0.6 microM) than 1S,3R-ACPD (EC50: 16 microM) and DHPG, a specific activator of group I mGluR, was a full agonist at PLD activation (EC50: 3.5 microM) indicating an involvement of a group I mGluR (mGluR1 and 5). MCPG and AIDA, two putative antagonists at mGluR1 receptors, caused a small but (in the case of MCPG) significant inhibition. DCG-IV, an activator of group II mGluR, was a weak partial agonist at PLD activation (EC50: 22 nM) while L-AP 4, an activator at group III mGluR, was totally inactive. Likewise, forskolin, a stimulant of cyclic AMP formation, was inactive either alone, or in combination with glutamatergic agonists. Pretreatment of the slices with pertussis toxin did not affect PLD activation. In summary, the glutamate-mediated activation of hippocampal PLD, which occurs transiently during postnatal development, is mediated by a group I mGluR, possibly involving mGluR5.
Collapse
Affiliation(s)
- J Klein
- Department of Pharmacology, University of Mainz, Germany
| | | | | | | | | |
Collapse
|
31
|
Libri V, Constanti A, Zibetti M, Postlethwaite M. Metabotropic glutamate receptor subtypes mediating slow inward tail current (IADP) induction and inhibition of synaptic transmission in olfactory cortical neurones. Br J Pharmacol 1997; 120:1083-95. [PMID: 9134221 PMCID: PMC1564578 DOI: 10.1038/sj.bjp.0701021] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
1. The pharmacological features of the pre- and postsynaptic metabotropic glutamate receptors (mGluRs) present in the guinea-pig olfactory cortex, were examined in brain slices in vitro by use of a conventional intracellular current clamp/voltage clamp recording technique. 2. Bath-application of trans-aminocyclopentane-1,3-dicarboxylic acid (trans-ACPD) (50 microM) produced a sustained membrane depolarization, increase in cell excitability and induction of a post-stimulus inward (after depolarizing) tail current (IADP) (measured under 'hybrid' voltage clamp) similar to those evoked by the muscarinic receptor agonist oxotremorine-M (OXO-M, 2 microM). 3. L-Glutamate (0.25 1 mM. in the presence of 20 microM 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) and 100 microM-DL-amino-5-phosphono valeric acid (DL-APV)) or the broad spectrum mGluR agonists 1S,3R-aminocyclopentane-1,3-dicarboxylic acid (1S,3R-ACPD, 10 microM), 1S,3S-ACPD (50 microM), ibotenate (Ibo; 25 microM. in the presence of 100 microM DL-APV), the selective mGluR I agonists (S)-3,5-dihydroxyphenylglycine ((S)-3,5-DHPG, 10 microM), (S)-3-hydroxyphenylglycine ((S)-3HPG, 50 microM), or quisqualate (10 microM, in the presence of 20 microM CNQX), but not the mGluR II agonist 2S,1'S,2'S-2-(2'-carboxycyclopropyl)-glycine (L-CCG1,1 microM) or mGluR III agonist L(+)-2-amino-4-phosphonobutyric acid (L-AP4, 1 mM), were all effective in producing membrane depolarization and inducing a post-stimulus IADP. Unexpectedly, the proposed mGluR II-selective agonist (2S,1'R,2'R,3'R)-2-(2',3'-dicarboxycyclopropyl)-glycine (DCG-IV, 10 microM, in the presence of 100 microM DL-APV) was also active. 4. The excitatory effects induced by 10 microM 1S,3R-ACPD were reversibly antagonized by the mGluR I/II antagonist (1)-alpha-methyl-4-carboxyphenylglycine ((+)-MCPG, 0.5 1 mM), as well as the selective mGluR I antagonists (S)-4-carboxyphenylglycine ((S)-4CPG) and (S)-4-carboxy-3-hydroxyphenyl glycine ((S)-4C3HPG) (both at 1 mM), but not the nonselective mGluR antagonist L(+)-2-amino-3-phosphonopropionic acid (L-AP3, 1 mM) or the selective mGluR III antagonist (S)-alpha-methyl-L-AP4 (MAP4, 1 mM). 5. The excitatory postsynaptic potentials (e.p.s.ps), induced by single focal stimulation of cortical excitatory fibre tracts, were markedly reduced by 1S,3R-ACPD or L-AP4 (both at 10 microM), and by the selective mGluR II agonists (mGluR 1 antagonists) (S)-4CPG or (S)-4C3HPG (both at 1 mM) but not (S)-3,5-DHPG or (S)-3HPG (both at 100 microM). 6. The inhibitory effects of 1S-3R-ACPD, but not L-AP4, were reversibly blocked by (+)-MCPG (1 mM), whereas those produced by L-AP4, but not 1S,3R-ACPD, were blocked by the selective mGluR III antagonist MAP4 (1 mM). 7. It is concluded that a group I mGluR is most likely involved in mediating excitatory postsynaptic effects, whereas two distinct mGluRs (e.g. group II and III) might serve as presynaptic inhibitory autoreceptors in the guinea-pig olfactory cortex.
Collapse
Affiliation(s)
- V Libri
- Department of Pharmacology, School of Pharmacy, London
| | | | | | | |
Collapse
|
32
|
Bedingfield JS, Jane DE, Kemp MC, Toms NJ, Roberts PJ. Novel potent selective phenylglycine antagonists of metabotropic glutamate receptors. Eur J Pharmacol 1996; 309:71-8. [PMID: 8864696 DOI: 10.1016/0014-2999(96)00313-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The metabotropic glutamate (mGlu) receptor antagonist properties of novel phenylglycine analogues were investigated in adult rat cortical slices (mGlu receptors negatively coupled to adenylyl cyclase), neonatal rat cortical slices and in cultured rat cerebellar granule cells (mGlu receptors coupled to phosphoinositide hydrolysis). (RS)-alpha-methyl-4-phosphonophenylglycine (MPPG), (RS)-alpha-methyl-4-sulphonophenylglycine (MSPG), (RS)-alpha-methyl-4-tetrazolylphenylglycine (MTPG), (RS)-alpha-methyl-3-carboxymethyl-4-hydroxyphenylglycine (M3CM4HPG) and (RS)-alpha-methyl-4-hydroxy-3-phosphonomethylphenylglycine (M4H3PMPG) were demonstrated to have potent and selective effects against 10 microM L-2-amino-4-phosphonobutyrate (L-AP4)- and 0.3 microM (2S,1'S,2'S)-2-(2-carboxycyclopropyl)glycine (L-CCG-1)-mediated inhibition of forskolin-stimulated cAMP accumulation in the adult rat cortex. In contrast, these compounds demonstrated either weak or no antagonism at mGlu receptors coupled to phosphoinositide hydrolysis in either neonatal rat cortex or in cultured cerebellar granule cells. These compounds thus appear to be useful discriminatory pharmacological tools for mGlu receptors and form the basis for the further development of novel antagonists.
Collapse
Affiliation(s)
- J S Bedingfield
- Department of Pharmacology, School of Medical Sciences, University of Bristol, UK
| | | | | | | | | |
Collapse
|
33
|
Schoepp DD, Salhoff CR, Wright RA, Johnson BG, Burnett JP, Mayne NG, Belagaje R, Wu S, Monn JA. The novel metabotropic glutamate receptor agonist 2R,4R-APDC potentiates stimulation of phosphoinositide hydrolysis in the rat hippocampus by 3,5-dihydroxyphenylglycine: evidence for a synergistic interaction between group 1 and group 2 receptors. Neuropharmacology 1996; 35:1661-72. [PMID: 9076745 DOI: 10.1016/s0028-3908(96)00121-9] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The mGlu receptor subtypes and second messenger pathways that mediate 1S,3R-1-aminocyclopentane-1,3-dicarboxylic acid (1S,3R-ACPD) responses in brain tissues are not fully understood. 1S,3R-ACPD differs from 3,5-dihydroxyphenylglycine (DHPG) or quisqualate in that 1S,3R-ACPD also activates group 2 mGlu receptors (mGlu2 and mGlu3) that are negatively linked to cAMP formation. To investigate the contribution of group 2 mGlu receptor activity of 1S,3R-ACPD to the phosphoinositide response in the rat hippocampus, we examined the effects of the novel group 2 mGlu receptor agonist 2R,4R-4-aminopyrrolidine-2,4-dicarboxylate (2R,4R-APDC). 2R,4R-APDC did not activate or inhibit group 1 mGlu receptors (human mGlu1 alpha and mGlu5a) or group 3 mGlu receptors (human mGlu4 and mGlu7), but potently decreased forskolin-stimulated cAMP formation in human mGlu2- and mGlu3-expressing cells. In slices of the adult rat hippocampus 2R,4R-APDC had no effect on basal phosphoinositide hydrolysis; however, it was found to greatly enhance phosphoinositide hydrolysis to DHPG or quisqualate. In the neonatal rat hippocampus, 2R,4R-APDC enhanced the potency of DHPG, while not affecting the maximal response to group 1 mGlu receptor agonists. Thus, the phosphoinositide response in the rat hippocampus to 1S,3R-ACPD is mediated by a synergistic interaction between group 1 and group 2 mGlu receptors.
Collapse
Affiliation(s)
- D D Schoepp
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN 46285, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Chapter 4. The Metabotropic Glutamate Receptors. ANNUAL REPORTS IN MEDICINAL CHEMISTRY 1996. [DOI: 10.1016/s0065-7743(08)60443-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
|
35
|
Buisson A, Yu SP, Choi DW. DCG-IV selectively attenuates rapidly triggered NMDA-induced neurotoxicity in cortical neurons. Eur J Neurosci 1996; 8:138-43. [PMID: 8713457 DOI: 10.1111/j.1460-9568.1996.tb01174.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Molecular cloning has revealed the existence of at least eight subtypes of metabotropic glutamate receptors (mGluRs). We examined the effect of (2S,1'R,2'R,3'R)-2-(2,3-dicarboxycyclopropyl)glycine (DCG-IV), a selective agonist of the mGluR 2/3 subtype, on excitotoxicity in mouse cortical cell cultures. Addition of DCG-IV to the exposure medium partially attenuated the rapidly triggered excitotoxic death induced by a 5 min exposure to 200 microM NMDA. This neuroprotective effect was reversed by coapplication of alpha-methyl-4-carboxyphenylglycine (MCPG), an antagonist of mGluRs, by pertussis toxin pretreatment and also by preincubation with dibutyryl cAMP, a stable analogue of cAMP. These results suggest that the activation of mGluR 2/3 is neuroprotective in our system. However, DCG-IV did not attenuate the slowly triggered neuronal death induced by 24 h exposure to low concentrations of NMDA, alpha-amino-1,3-cyclopentanedicarboxylic acid (AMPA) or kainate. The failure of DCG-IV to block slowly triggered NMDA neurotoxicity is likely due to weak NMDA agonist activity, as demonstrated in whole-cell recording.
Collapse
Affiliation(s)
- A Buisson
- Department of Neurology, Washington University School of Medicine, St Louis, MO 63110, USA
| | | | | |
Collapse
|
36
|
Bruno V, Battaglia G, Copani A, Giffard RG, Raciti G, Raffaele R, Shinozaki H, Nicoletti F. Activation of class II or III metabotropic glutamate receptors protects cultured cortical neurons against excitotoxic degeneration. Eur J Neurosci 1995; 7:1906-13. [PMID: 8528465 DOI: 10.1111/j.1460-9568.1995.tb00712.x] [Citation(s) in RCA: 124] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Trans-1-aminocyclopentane-1,3-dicarboxylic acid, a mixed agonist of all metabotropic glutamate receptor (mGluR) subtypes, is known to produce either neurotoxic or neuroprotective effects. We have therefore hypothesized that individual mGluR subtypes differentially affect neurodegenerative processes. Selective agonists of subtypes which belong to mGluR class II or III, such as (2S,1'R,2'R,3'R)-2-(2,3-dicarboxycyclopropyl)-glycine (DCG-IV) (specific for subtypes mGluR4, 6 or 7), were highly potent and efficacious in protecting cultured cortical neurons against toxicity induced by either a transient exposure to N-methyl-D-aspartate (NMDA) or a prolonged exposure to kainate. In contrast, agonists that preferentially activate class I mGluR subtypes (mGluR1 or 5), such as quisqualate or trans-azetidine-2,3-dicarboxylic acid, were inactive. DCG-IV was still neuroprotective when applied to cultures after the toxic pulse with NMDA. This delayed rescue effect was associated with a reduction in the release of endogenous glutamate, a process that contributes to the maturation of neuronal damage. We conclude that agonists of class II or III mGluRs are of potential interest in the experimental therapy of acute or chronic neurodegenerative disorders.
Collapse
Affiliation(s)
- V Bruno
- Institute of Pharmacology, University of Catania, Italy
| | | | | | | | | | | | | | | |
Collapse
|
37
|
Ishida M, Saitoh T, Tsuji K, Nakamura Y, Kataoka K, Shinozaki H. Novel agonists for metabotropic glutamate receptors: trans- and cis-2-(2-carboxy-3-methoxymethylcyclopropyl)glycine (trans- and cis-MCG-I). Neuropharmacology 1995; 34:821-7. [PMID: 8532163 DOI: 10.1016/0028-3908(95)00084-j] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
New derivatives of 2-(carboxycyclopropyl)glycine (CCG), (2S,1'S,2'R,3'S)- and (2S,1'S,2'R,3'R)-2-(2-carboxy-3-methoxymethylcyclopropyl) glycine (trans- and cis-MCG-I), effectively inhibited forskolin-stimulated cyclic AMP formation in a concentration dependent manner in cultured spinal neurones of rats. They effectively depressed monosynaptic excitation in the spinal reflex of newborn rats with IC50 values of 0.3 and 3 microM, respectively, which was sensitive to (+)-MCPG. They did not cause any depolarization even when the concentration was increased up to 0.3 mM. However, after treatment with quisqualate, cis-MCG-I caused a depolarization of motoneurones in the newborn rat spinal cord in a concentration dependent manner with a threshold concentration of 1 microM (quisqualate effect). The depolarizing activity developed after quisqualate treatment gradually decreased but lasted for more than 2 hr. The depolarization induced by cis-MCG-I seemed pharmacologically similar to that of phosphonate-containing analogues of glutamate such as L-AP4 or L-AP6 under the "quisqualate effect". These novel CCG derivatives would be expected to provide useful probes for elucidating the physiological function of mGluRs.
Collapse
Affiliation(s)
- M Ishida
- Department of Pharmacology, Tokyo Metropolitan Institute of Medical Science, Japan
| | | | | | | | | | | |
Collapse
|