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Bedini A, Boutin JA, Legros C, Zlotos DP, Spadoni G. Industrial and academic approaches to the search for alternative melatonin receptor ligands: An historical survey. J Pineal Res 2024; 76:e12953. [PMID: 38682544 DOI: 10.1111/jpi.12953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Revised: 03/05/2024] [Accepted: 03/24/2024] [Indexed: 05/01/2024]
Abstract
The search for melatonin receptor agonists formed the main part of melatonin medicinal chemistry programs for the last three decades. In this short review, we summarize the two main aspects of these programs: the development of all the necessary tools to characterize the newly synthesized ligands at the two melatonin receptors MT1 and MT2, and the medicinal chemist's approaches to find chemically diverse ligands at these receptors. Both strategies are described. It turns out that the main source of tools were industrial laboratories, while the medicinal chemistry was mainly carried out in academia. Such complete accounts are interesting, as they delineate the spirits in which the teams were working demonstrating their strength and innovative character. Most of the programs were focused on nonselective agonists and few of them reached the market. In contrast, discovery of MT1-selective agonists and melatonergic antagonists with proven in vivo activity and MT1 or MT2-selectivity is still in its infancy, despite the considerable interest that subtype selective compounds may bring in the domain, as the physiological respective roles of the two subtypes of melatonin receptors, is still poorly understood. Poly-pharmacology applications and multitarget ligands have also been considered.
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MESH Headings
- Ligands
- Humans
- Animals
- Receptor, Melatonin, MT2/metabolism
- Receptor, Melatonin, MT2/agonists
- Receptor, Melatonin, MT1/metabolism
- Receptor, Melatonin, MT1/agonists
- Receptor, Melatonin, MT1/antagonists & inhibitors
- Receptors, Melatonin/metabolism
- Receptors, Melatonin/agonists
- Melatonin/metabolism
- History, 20th Century
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Affiliation(s)
- Annalida Bedini
- Dipartimento di Scienze Biomolecolari, Università degli Studi di Urbino Carlo Bo, Urbino, Italy
| | - Jean A Boutin
- Laboratory of Neuroendocrine Endocrine and Germinal Differentiation and Communication (NorDiC), Univ Rouen Normandie, Inserm, NorDiC, Rouen, France
| | | | - Darius P Zlotos
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy and Biotechnology, The German University in Cairo, New Cairo City, Egypt
| | - Gilberto Spadoni
- Dipartimento di Scienze Biomolecolari, Università degli Studi di Urbino Carlo Bo, Urbino, Italy
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2
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Melatonin Activates Anti-Inflammatory Features in Microglia in a Multicellular Context: Evidence from Organotypic Brain Slices and HMC3 Cells. Biomolecules 2023; 13:biom13020373. [PMID: 36830742 PMCID: PMC9952958 DOI: 10.3390/biom13020373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 02/13/2023] [Accepted: 02/14/2023] [Indexed: 02/18/2023] Open
Abstract
Melatonin (MEL) is a neurohormone endowed with neuroprotective activity, exerted both directly on neuronal cells and indirectly through modulation of responsive glial cells. In particular, MEL's effects on microglia are receptor-mediated and in part dependent on SIRT1 activation. In the present study, we exploited the highly preserved cytoarchitecture of organotypic brain cultures (OC) to explore the effects of MEL on hippocampal microglia in a 3D context as compared to a single cell type context represented by the human HMC3 cell line. We first evaluated the expression of MEL receptor MT1 and SIRT1 and then investigated MEL action against an inflammatory stimulation with LPS: OCs were cultured for a total of 2 weeks and during this time exposed to 0.1 μg/mL of LPS for 24 h either on day 1 (LPS 1°) or on day 11 (LPS 11°). MEL was added immediately after plating and kept for the entire experiment. Under these conditions, both MEL and LPS induced amoeboid microglia. However, the same round phenotype matched different polarization features. LPS increased the number of nuclear-NF-kB+ round cells and MEL alone or in combination with LPS increased BDNF+ round microglia. In addition, MEL contrasted LPS effects on NF-kB expression. Data from HMC3 microglia confirmed MEL's anti-inflammatory effects against LPS in terms of CASP1 induction and BDNF release, identifying SIRT1 as a mediator. However, no effects were evident for MEL alone on HMC3 microglia. Overall, our results point to the importance of the multicellular context for full MEL activity, especially in a preventive view, and support the use of OCs as a favorable model to explore inflammatory responses.
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Caniceiro AB, Bueschbell B, Schiedel AC, Moreira IS. Class A and C GPCR Dimers in Neurodegenerative Diseases. Curr Neuropharmacol 2022; 20:2081-2141. [PMID: 35339177 PMCID: PMC9886835 DOI: 10.2174/1570159x20666220327221830] [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: 09/14/2021] [Revised: 02/21/2022] [Accepted: 03/23/2022] [Indexed: 11/22/2022] Open
Abstract
Neurodegenerative diseases affect over 30 million people worldwide with an ascending trend. Most individuals suffering from these irreversible brain damages belong to the elderly population, with onset between 50 and 60 years. Although the pathophysiology of such diseases is partially known, it remains unclear upon which point a disease turns degenerative. Moreover, current therapeutics can treat some of the symptoms but often have severe side effects and become less effective in long-term treatment. For many neurodegenerative diseases, the involvement of G proteincoupled receptors (GPCRs), which are key players of neuronal transmission and plasticity, has become clearer and holds great promise in elucidating their biological mechanism. With this review, we introduce and summarize class A and class C GPCRs, known to form heterodimers or oligomers to increase their signalling repertoire. Additionally, the examples discussed here were shown to display relevant alterations in brain signalling and had already been associated with the pathophysiology of certain neurodegenerative diseases. Lastly, we classified the heterodimers into two categories of crosstalk, positive or negative, for which there is known evidence.
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Affiliation(s)
- Ana B. Caniceiro
- Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; ,These authors contributed equally to this work.
| | - Beatriz Bueschbell
- PhD Programme in Experimental Biology and Biomedicine, Institute for Interdisciplinary Research (IIIUC), University of Coimbra, Casa Costa Alemão, 3030-789 Coimbra, Portugal; ,These authors contributed equally to this work.
| | - Anke C. Schiedel
- Department of Pharmaceutical & Medicinal Chemistry, Pharmaceutical Institute, University of Bonn, D-53121 Bonn, Germany;
| | - Irina S. Moreira
- University of Coimbra, Department of Life Sciences, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal; ,Center for Neuroscience and Cell Biology, Center for Innovative Biomedicine and Biotechnology, 3004-504 Coimbra, Portugal,Address correspondence to this author at the Center for Neuroscience and Cell Biology, Center for Innovative Biomedicine and Biotechnology, 3004-504 Coimbra, Portugal; E-mail:
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4
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Melatonin secretion, molecular expression and evolution of MT1/2 in two Lasiopodomys species. Mamm Biol 2022. [DOI: 10.1007/s42991-021-00204-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Legros C, Yous S, Boutin JA. Alternative Ligands at Melatonin Receptors. Methods Mol Biol 2022; 2550:151-162. [PMID: 36180688 DOI: 10.1007/978-1-0716-2593-4_19] [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] [Indexed: 06/16/2023]
Abstract
Melatonin (N-acetyl-5-methoxytryptamine) is a neurohormone that possesses a wide range of biological effects. Most of the main recognized effects of this hormone in mammals are due to its interaction with two G protein-coupled receptors, MT1 and MT2. Ligand-binding studies have been based on the use of its radioligand analog, 2[125I]-iodomelatonin, a super agonist discovered in the early 1990s. This compound has been used in most of the binding studies reported in the literature. Nevertheless, more recently other possibilities arose. This chapter is a brief summary of those alternative radioligands and of their benefits one can find in using them.
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Affiliation(s)
- Céline Legros
- Pole d'expertise Biotechnologie, Chimie & Biologie, Institut de Recherches Servier, Croissy-sur-Seine, France
- Eurofins Discovery, Celle l'Evescault, France
| | - Said Yous
- UMR-S 1172-LiNC-Lille Neuroscience & Cognition, Lille, France
| | - Jean A Boutin
- Pole d'expertise Biotechnologie, Chimie & Biologie, Institut de Recherches Servier, Croissy-sur-Seine, France.
- PHARMADEV (Pharmacochimie et biologie pour le développement), Faculté de Pharmacie, Toulouse, France.
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6
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Bonnaud A, Dupré C, Legros C, Boutin JA. MT1 Receptor Signaling Pathways by Impedance Measurement. Methods Mol Biol 2022; 2550:201-206. [PMID: 36180694 DOI: 10.1007/978-1-0716-2593-4_25] [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] [Indexed: 06/16/2023]
Abstract
Melatonin exerts its classical effects of relay of the circadian rhythm through two G protein-coupled receptors, MT1 and MT2. The functions attributed to melatonin are so numerous that the action of this neurohormone should be through several protein targets or through new coupled biochemistry routes at its receptors. In order to better explore and understand these melatonin-dependent activities, we enlarged the functional pathways linked to the activation of the receptors in living system. Impedance has been shown to rely on the shape-shifting capacity of receptor-associated mechanisms. Those changes elicited by an agonist lead to changes in the actual shape of the cells, and thus to their electric conductivity. The impact of those changes onto the physiology of the cells is not completely understood from a mechanistic point of view, but the measure of these changes associated with various ligands at the melatonin receptor(s) might bring new information on melatonin-dependent cell reactivity. The following chapter is a detailed account of the way impedance can be measured in MT1-experssing cells.
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Affiliation(s)
- Anne Bonnaud
- Pole d'expertise Biotechnologie, Chimie & Biologie, Institut de Recherches Servier, Croissy-sur-Seine, France
| | - Clémence Dupré
- Pole d'expertise Biotechnologie, Chimie & Biologie, Institut de Recherches Servier, Croissy-sur-Seine, France
| | - Céline Legros
- Pole d'expertise Biotechnologie, Chimie & Biologie, Institut de Recherches Servier, Croissy-sur-Seine, France
- Eurofins Discovery, Celle l'Evescault, France
| | - Jean A Boutin
- Pole d'expertise Biotechnologie, Chimie & Biologie, Institut de Recherches Servier, Croissy-sur-Seine, France.
- PHARMADEV (Pharmacochimie et biologie pour le développement), Faculté de Pharmacie, Toulouse, France.
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7
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Gautier C, Theret I, Lizzo G, Ferry G, Guénin SP, Boutin JA. Why Are We Still Cloning Melatonin Receptors? A Commentary. Methods Mol Biol 2022; 2550:267-281. [PMID: 36180698 DOI: 10.1007/978-1-0716-2593-4_29] [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] [Indexed: 06/16/2023]
Abstract
Cloning may seem to be a view from the past. The time before software, computers and AI were invented. It seems to us worth discussing these points in view of our favorite target: the melatoninergic system. In a few stances, it might be important to point out that even in the new era of dry science, there is still a need to experiment and to prove at the bench that our in silico assertions are right. Most of the living animals express to some extend the melatonin receptors. Some of these animal genomes were completely or partially sequenced, and it is tempting to extract from this huge information the sequence(s) of our favorite genes (MLT receptors). Then, why bother cloning, as opposed to simply built the gene and express it in a host cell? Because the genetic boundaries of the expressed sequence(s) are not 100% sure. Because the melatonin receptor gene(s) comprise a first exon 25,000 base pair far from the second one and the limits between this Ex1 and In1-as between In1 and Ex2-are subject to changes that might have a huge impact on the biochemical properties of the receptor, once expressed. Because a receptor is a biochemical entity with characteristics that are important for the functioning of this particular pathway, and more generally, for the functioning of life.
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Affiliation(s)
- Célia Gautier
- Pôle d'expertise Biotechnologie, Chimie & Biologie, Institut de Recherches Servier, Croissy-sur-Seine, France
| | - Isabelle Theret
- Pôle d'expertise Biotechnologie, Chimie & Biologie, Institut de Recherches Servier, Croissy-sur-Seine, France
| | - Giulia Lizzo
- Pôle d'expertise Biotechnologie, Chimie & Biologie, Institut de Recherches Servier, Croissy-sur-Seine, France
| | - Gilles Ferry
- Pôle d'expertise Biotechnologie, Chimie & Biologie, Institut de Recherches Servier, Croissy-sur-Seine, France
| | - Sophie-Pénélope Guénin
- Pôle d'expertise Biotechnologie, Chimie & Biologie, Institut de Recherches Servier, Croissy-sur-Seine, France
| | - Jean A Boutin
- Pôle d'expertise Biotechnologie, Chimie & Biologie, Institut de Recherches Servier, Croissy-sur-Seine, France.
- Pharma-Dev (Pharmacochimie et Biologie pour le Développement), Faculté de Pharmacie, UMR 152, Université de Toulouse, Toulouse, France.
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Shabajee-Alibay P, Bonnaud A, Malpaux B, Delagrange P, Audinot V, Yous S, Boutin JA, Stephan JP, Leprince J, Legros C. A putative new melatonin binding site in sheep brain, MTx: preliminary observations and characteristics. J Pharmacol Exp Ther 2021; 380:JPET-AR-2021-000785. [PMID: 34706966 DOI: 10.1124/jpet.121.000785] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 09/29/2021] [Accepted: 10/22/2021] [Indexed: 11/22/2022] Open
Abstract
In mammals, MT1 and MT2 melatonin receptors are high affinity G protein-coupled receptors and are thought to be involved in the integration of the melatonin signaling throughout the brain and periphery. In the present study, we describe a new melatonin binding site, named MTx, with a peculiar pharmacological profile. This site had a low affinity for 2-[125I]-melatonin in saturation assays in hypothalamus and retina (pKD = 9.13 {plus minus} 0.05, Bmax = 1.12 {plus minus} 0.11 fmol/mg protein and pKD = 8.81 {plus minus} 0.50, Bmax = 7.65 {plus minus} 2.64 fmol/mg protein, respectively) and a very high affinity, in competition assays, for melatonin (pKi = 13.08 {plus minus} 0.18), and other endogenous compounds. Using autoradiography, we showed a preferential localization of the MTx in periventricular areas of the sheep brain, with a density 3 to 8 times higher than those observed for ovine MT1 In addition, using a set of well-characterized ligands, we showed that this site did not correspond to any of the following receptors: MT1, MT2, MT3 , D1, D2, noradrenergic, nor 5-HT2 Based on its affinity for melatonin, MTx did not seem to be implicated in the integration of cerebral melatonin concentration variations since they were saturating for MTx. Nevertheless, it remained of prime importance because of its periventricular distribution, in close contact with the CSF, and its peculiar pharmacological profile responding to both melatoninergic and serotoninergic compounds. Significance Statement Herein a putative new melatonin binding site is described in sheep brain parts in close contact with the 3rd ventricle. The characteristics of the pharmacological profile of this site is different from anything previously reported in the literature. The present work forms the basis of future full pharmacological characterization.
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Affiliation(s)
- Preety Shabajee-Alibay
- Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Normandie Université, UNIROUEN, INSERM 1239, France
| | | | - Benoit Malpaux
- UMR Physiologie de la Reproduction et des Comportements, INRA Val de Loire, France
| | | | | | - Said Yous
- UMR-S 1172-LiNC-Lille Neuroscience & Cognition, Univ. Lille, INSERM, CHU Lille, France
| | - Jean A Boutin
- Institut de Recherches Internationales Servier, France
| | | | - Jérôme Leprince
- Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Normandie Université, UNIROUEN, INSERM 1239, France
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Molcan L, Maier A, Zemančíková A, Gelles K, Török J, Zeman M, Ellinger I. Expression of Melatonin Receptor 1 in Rat Mesenteric Artery and Perivascular Adipose Tissue and Vasoactive Action of Melatonin. Cell Mol Neurobiol 2021; 41:1589-1598. [PMID: 32734322 PMCID: PMC8408066 DOI: 10.1007/s10571-020-00928-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 07/20/2020] [Indexed: 12/26/2022]
Abstract
Melatonin is released by the pineal gland and can modulate cardiovascular system function via the G protein-coupled melatonin receptors MT1 and MT2. Most vessels are surrounded by perivascular adipose tissue (PVAT), which affects their contractility. The aim of our study was to evaluate mRNA and protein expression of MT1 and MT2 in the mesenteric artery (MA) and associated PVAT of male rats by RT-PCR and Western blot. Receptor localization was further studied by immunofluorescence microscopy. Effects of melatonin on neurogenic contractions were explored in isolated superior MA ex vivo by measurement of isometric contractile tension. MT1, but not MT2, was present in MA, and MT1 was localized mainly in vascular smooth muscle. Moreover, we proved the presence of MT1, but not MT2 receptors, in MA-associated PVAT. In isolated superior MA with intact PVAT, neuro-adrenergic contractile responses were significantly smaller when compared to arteries with removed PVAT. Pre-treatment with melatonin of PVAT-stripped arterial rings enhanced neurogenic contractions, while the potentiating effect of melatonin was not detected in preparations with preserved PVAT. We hypothesize that melatonin can stimulate the release of PVAT-derived relaxing factor(s) via MT1, which can override the direct pro-contractile effect of melatonin on vascular smooth muscle. Our results suggest that melatonin is involved in the control of vascular tone in a complex way, which is vessel specific and can reflect a sum of action on different layers of the vessel wall and surrounding PVAT.
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Affiliation(s)
- Lubos Molcan
- Department of Animal Physiology and Ethology, Faculty of Natural Sciences, Comenius University Bratislava, Bratislava, Slovakia
| | - Andreas Maier
- Institute for Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Medical University Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Anna Zemančíková
- Institute of Normal and Pathological Physiology, Centre of Experimental Medicine, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Katharina Gelles
- Institute for Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Medical University Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Jozef Török
- Institute of Normal and Pathological Physiology, Centre of Experimental Medicine, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Michal Zeman
- Department of Animal Physiology and Ethology, Faculty of Natural Sciences, Comenius University Bratislava, Bratislava, Slovakia
| | - Isabella Ellinger
- Institute for Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Medical University Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
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Lépinay J, Taragnat C, Dubois JP, Chesneau D, Jockers R, Delagrange P, Bozon V. Negative regulation of melatonin secretion by melatonin receptors in ovine pinealocytes. PLoS One 2021; 16:e0255249. [PMID: 34324562 PMCID: PMC8320996 DOI: 10.1371/journal.pone.0255249] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 07/12/2021] [Indexed: 01/01/2023] Open
Abstract
Melatonin (MLT) is a biological modulator of circadian and seasonal rhythms and reproduction. The photoperiodic information is detected by retinal photoreceptors and transmitted through nerve transmissions to the pineal gland, where MLT is synthesized and secreted at night into the blood. MLT interacts with two G protein-coupled receptors, MT1 and MT2. The aim of our work was to provide evidence for the presence of MLT receptors in the ovine pineal gland and define their involvement on melatonin secretion. For the first time, we identified the expression of MLT receptors with the specific 2-[125I]-MLT agonistic radioligand in ovin pinealocytes. The values of Kd and Bmax are 2.24 ± 1.1 nM and 20 ± 6.8 fmol/mg. MLT receptors are functional and inhibit cAMP production and activate ERK1/2 through pertussis toxin-sensitive Gi/o proteins. The MLT receptor antagonist/ inverse agonist luzindole increased cAMP production (189 ± 30%) and MLT secretion (866 ± 13%). The effect of luzindole on MLT secretion was additive with the effect of well-described activators of this pathway such as the β-adrenergic agonist isoproterenol and the α-adrenergic agonist phenylephrine. Co-incubation of all three compounds increased MLT secretion by 1236 ± 199%. These results suggest that MLT receptors are involved in the negative regulation of the synthesis of its own ligand in pinealocytes. While adrenergic receptors promote MLT secretion, MLT receptors mitigate this effect to limit the quantity of MLT secreted by the pineal gland.
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Affiliation(s)
- Julie Lépinay
- Physiologie de la Reproduction et des Comportements, Université de Tours, Nouzilly, France
| | - Catherine Taragnat
- Physiologie de la Reproduction et des Comportements, Université de Tours, Nouzilly, France
| | - Jean-Philippe Dubois
- Physiologie de la Reproduction et des Comportements, Université de Tours, Nouzilly, France
| | - Didier Chesneau
- Physiologie de la Reproduction et des Comportements, Université de Tours, Nouzilly, France
| | - Ralf Jockers
- Université de Paris, Institut Cochin, INSERM, CNRS, Paris, France
| | | | - Véronique Bozon
- Physiologie de la Reproduction et des Comportements, Université de Tours, Nouzilly, France
- * E-mail:
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Veronesi VB, Pioli MR, de Souza DN, Teixeira CJ, Murata GM, Santos-Silva JC, Hecht FB, Vicente JM, Bordin S, Anhê GF. Agomelatine reduces circulating triacylglycerides and hepatic steatosis in fructose-treated rats. Biomed Pharmacother 2021; 141:111807. [PMID: 34120066 DOI: 10.1016/j.biopha.2021.111807] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 05/28/2021] [Accepted: 06/07/2021] [Indexed: 11/16/2022] Open
Abstract
Agomelatine (AGO) is an antidepressant drug with agonistic activity at melatonin receptor 1 (MT1) and MT2 and with neutral antagonistic activity at serotonin receptor 5-HT2C. Although experimental studies show that melatonin reduces hypertriglyceridemia and hepatic steatosis induced by excessive fructose intake, no studies have tested if AGO exerts similar actions. To address this issue we have treated male Wistar rats with fructose (15% in the drinking water) and/or AGO (40 mg/kg/day) for two weeks. AGO reduced body weight gain, feeding efficiency and hepatic lipid levels without affecting caloric intake in fructose-treated rats. AGO has also decreased very low-density lipoprotein (VLDL) production and circulating TAG levels after an oral load with olive oil. Accordingly, treatment with AGO reduced the hepatic expression of fatty acid synthase (Fasn), a limiting step for hepatic de novo lipogenesis (DNLG). The expression of apolipoprotein B (Apob) and microsomal triglyceride transfer protein (Mttp) in the ileum, two crucial proteins for intestinal lipoprotein production, were also downregulated by treatment with AGO. Altogether, the present data show that AGO mimics the metabolic benefits of melatonin when used in fructose-treated rats. This study also suggests that it is relevant to evaluate the potential of AGO to treat metabolic disorders in future clinical trials.
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Affiliation(s)
- Vanessa Barbosa Veronesi
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas, 105 Alexander Flemming St., Zip Code: 13083-881, Campinas, SP, Brazil
| | - Mariana Rodrigues Pioli
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas, 105 Alexander Flemming St., Zip Code: 13083-881, Campinas, SP, Brazil
| | - Dailson Nogueira de Souza
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas, 105 Alexander Flemming St., Zip Code: 13083-881, Campinas, SP, Brazil
| | - Caio Jordão Teixeira
- Department of Physiology and Biophysics, Institute of Biomedical Science, University of Sao Paulo, 1524 Prof. Lineu Prestes Ave., ICB 1, Zip Code: 05508-000, Sao Paulo, SP, Brazil
| | - Gilson Masahiro Murata
- Department of Physiology and Biophysics, Institute of Biomedical Science, University of Sao Paulo, 1524 Prof. Lineu Prestes Ave., ICB 1, Zip Code: 05508-000, Sao Paulo, SP, Brazil
| | - Junia Carolina Santos-Silva
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas, 105 Alexander Flemming St., Zip Code: 13083-881, Campinas, SP, Brazil
| | - Fernanda Ballerini Hecht
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas, 105 Alexander Flemming St., Zip Code: 13083-881, Campinas, SP, Brazil
| | - Julia Modesto Vicente
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas, 105 Alexander Flemming St., Zip Code: 13083-881, Campinas, SP, Brazil
| | - Silvana Bordin
- Department of Physiology and Biophysics, Institute of Biomedical Science, University of Sao Paulo, 1524 Prof. Lineu Prestes Ave., ICB 1, Zip Code: 05508-000, Sao Paulo, SP, Brazil
| | - Gabriel Forato Anhê
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas, 105 Alexander Flemming St., Zip Code: 13083-881, Campinas, SP, Brazil.
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Melhuish Beaupre LM, Brown GM, Gonçalves VF, Kennedy JL. Melatonin's neuroprotective role in mitochondria and its potential as a biomarker in aging, cognition and psychiatric disorders. Transl Psychiatry 2021; 11:339. [PMID: 34078880 PMCID: PMC8172874 DOI: 10.1038/s41398-021-01464-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 04/16/2021] [Accepted: 05/14/2021] [Indexed: 02/05/2023] Open
Abstract
Melatonin is an ancient molecule that is evident in high concentrations in various tissues throughout the body. It can be separated into two pools; one of which is synthesized by the pineal and can be found in blood, and the second by various tissues and is present in these tissues. Pineal melatonin levels display a circadian rhythm while tissue melatonin does not. For decades now, melatonin has been implicated in promoting and maintaining sleep. More recently, evidence indicates that it also plays an important role in neuroprotection. The beginning of our review will summarize this literature. As an amphiphilic, pleiotropic indoleamine, melatonin has both direct actions and receptor-mediated effects. For example, melatonin has established effects as an antioxidant and free radical scavenger both in vitro and in animal models. This is also evident in melatonin's prominent role in mitochondria, which is reviewed in the next section. Melatonin is synthesized in, taken up by, and concentrated in mitochondria, the powerhouse of the cell. Mitochondria are also the major source of reactive oxygen species as a byproduct of mitochondrial oxidative metabolism. The final section of our review summarizes melatonin's potential role in aging and psychiatric disorders. Pineal and tissue melatonin levels both decline with age. Pineal melatonin declines in individuals suffering from psychiatric disorders. Melatonin's ability to act as a neuroprotectant opens new avenues of exploration for the molecule as it may be a potential treatment for cases with neurodegenerative disease.
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Affiliation(s)
- Lindsay M Melhuish Beaupre
- Molecular Brain Science Research Department, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
| | - Gregory M Brown
- Molecular Brain Science Research Department, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Vanessa F Gonçalves
- Molecular Brain Science Research Department, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - James L Kennedy
- Molecular Brain Science Research Department, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada.
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada.
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada.
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13
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Legros C, Dupré C, Brasseur C, Bonnaud A, Bruno O, Valour D, Shabajee P, Giganti A, Nosjean O, Kenakin TP, Boutin JA. Characterization of the various functional pathways elicited by synthetic agonists or antagonists at the melatonin MT 1 and MT 2 receptors. Pharmacol Res Perspect 2020; 8:e00539. [PMID: 31893123 PMCID: PMC6935685 DOI: 10.1002/prp2.539] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 09/30/2019] [Accepted: 10/10/2019] [Indexed: 12/20/2022] Open
Abstract
Melatonin is a neurohormone that translates the circadian rhythm to the peripheral organs through a series of binding sites identified as G protein-coupled receptors MT1 and MT2. Due to minute amounts of receptor proteins in target organs, the main tool of studies of the melatoninergic system is recombinant expression of the receptors in cellular hosts. Although a number of studies exist on these receptors, studies of several signaling pathways using a large number of melatoninergic compounds are rather limited. We chose to fill this gap to better describe a panel of compounds that have been only partially characterized in terms of functionality. First, we characterized HEK cells expressing MT1 or MT2, and several signaling routes with melatonin itself to validate the approach: GTPγS, cAMP production, internalization, β-arrestin recruitment, and cell morphology changes (CellKey ® ). Second, we chose 21 compounds from our large melatoninergic chemical library and characterized them using this panel of signaling pathways. Notably, antagonists were infrequent, and their functionality depended largely on the pathway studied. This will permit redefining the availability of molecular tools that can be used to better understand the in situ activity and roles of these receptors.
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Affiliation(s)
- Céline Legros
- Pôle d’Expertise BiotechnologieChimie & BiologieInstitut de Recherches ServierCroissy‐sur‐SeineFrance
| | - Clémence Dupré
- Pôle d’Expertise BiotechnologieChimie & BiologieInstitut de Recherches ServierCroissy‐sur‐SeineFrance
| | - Chantal Brasseur
- Pôle d’Expertise BiotechnologieChimie & BiologieInstitut de Recherches ServierCroissy‐sur‐SeineFrance
| | - Anne Bonnaud
- Pôle d’Expertise BiotechnologieChimie & BiologieInstitut de Recherches ServierCroissy‐sur‐SeineFrance
| | - Olivier Bruno
- Pôle d’Expertise BiotechnologieChimie & BiologieInstitut de Recherches ServierCroissy‐sur‐SeineFrance
| | - Damien Valour
- Pôle d’Expetise Méthodologie et Valorisation des DonnéesInstitut de Recherches Internationales ServierSuresnesFrance
| | - Preety Shabajee
- Pôle d’Expertise BiotechnologieChimie & BiologieInstitut de Recherches ServierCroissy‐sur‐SeineFrance
| | - Adeline Giganti
- Pôle d’Expertise BiotechnologieChimie & BiologieInstitut de Recherches ServierCroissy‐sur‐SeineFrance
| | - Olivier Nosjean
- Pôle d’Expertise BiotechnologieChimie & BiologieInstitut de Recherches ServierCroissy‐sur‐SeineFrance
- Present address:
Institut de Recherches Internationales SERVIERSuresnesFrance
| | - Terrence P. Kenakin
- Department of PharmacologyUniversity of North Carolina School of MedicineChapel HillNCUSA
| | - Jean A. Boutin
- Pôle d’Expertise BiotechnologieChimie & BiologieInstitut de Recherches ServierCroissy‐sur‐SeineFrance
- Present address:
Institut de Recherches Internationales SERVIERSuresnesFrance
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14
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Cecon E, Ivanova A, Luka M, Gbahou F, Friederich A, Guillaume JL, Keller P, Knoch K, Ahmad R, Delagrange P, Solimena M, Jockers R. Detection of recombinant and endogenous mouse melatonin receptors by monoclonal antibodies targeting the C-terminal domain. J Pineal Res 2019; 66:e12540. [PMID: 30475390 DOI: 10.1111/jpi.12540] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 11/04/2018] [Accepted: 11/16/2018] [Indexed: 02/06/2023]
Abstract
Melatonin receptors play important roles in the regulation of circadian and seasonal rhythms, sleep, retinal functions, the immune system, depression, and type 2 diabetes development. Melatonin receptors are approved drug targets for insomnia, non-24-hour sleep-wake disorders, and major depressive disorders. In mammals, two melatonin receptors (MTRs) exist, MT1 and MT2 , belonging to the G protein-coupled receptor (GPCR) superfamily. Similar to most other GPCRs, reliable antibodies recognizing melatonin receptors proved to be difficult to obtain. Here, we describe the development of the first monoclonal antibodies (mABs) for mouse MT1 and MT2 . Purified antibodies were extensively characterized for specific reactivity with mouse, rat, and human MT1 and MT2 by Western blot, immunoprecipitation, immunofluorescence, and proximity ligation assay. Several mABs were specific for either mouse MT1 or MT2 . None of the mABs cross-reacted with rat MTRs, and some were able to react with human MTRs. The specificity of the selected mABs was validated by immunofluorescence microscopy in three established locations (retina, suprachiasmatic nuclei, pituitary gland) for MTR expression in mice using MTR-KO mice as control. MT2 expression was not detected in mouse insulinoma MIN6 cells or pancreatic beta-cells. Collectively, we report the first monoclonal antibodies recognizing recombinant and native mouse melatonin receptors that will be valuable tools for future studies.
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Affiliation(s)
- Erika Cecon
- Inserm U1016, Institut Cochin, Paris, France
- CNRS UMR 8104, Paris, France
- Sorbonne Paris Cité, Univ. Paris Descartes, Paris, France
| | - Anna Ivanova
- Molecular Diabetology, Faculty of Medicine, University Hospital, TU Dresden, Dresden, Germany
- Faculty of Medicine, Paul Langerhans Institute Dresden (PLID) of the Helmholtz Center Munich at University Hospital Carl Gustav Carus, TU Dresden, Dresden, Germany
- German Center for Diabetes Research (DZD), Munich Neuherberg, Germany
| | - Marine Luka
- Inserm U1016, Institut Cochin, Paris, France
- CNRS UMR 8104, Paris, France
- Sorbonne Paris Cité, Univ. Paris Descartes, Paris, France
| | - Florence Gbahou
- Inserm U1016, Institut Cochin, Paris, France
- CNRS UMR 8104, Paris, France
- Sorbonne Paris Cité, Univ. Paris Descartes, Paris, France
| | - Anne Friederich
- Molecular Diabetology, Faculty of Medicine, University Hospital, TU Dresden, Dresden, Germany
- Faculty of Medicine, Paul Langerhans Institute Dresden (PLID) of the Helmholtz Center Munich at University Hospital Carl Gustav Carus, TU Dresden, Dresden, Germany
- German Center for Diabetes Research (DZD), Munich Neuherberg, Germany
| | - Jean-Luc Guillaume
- Inserm U1016, Institut Cochin, Paris, France
- CNRS UMR 8104, Paris, France
- Sorbonne Paris Cité, Univ. Paris Descartes, Paris, France
| | - Patrick Keller
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden, Germany
| | - Klaus Knoch
- Molecular Diabetology, Faculty of Medicine, University Hospital, TU Dresden, Dresden, Germany
- Faculty of Medicine, Paul Langerhans Institute Dresden (PLID) of the Helmholtz Center Munich at University Hospital Carl Gustav Carus, TU Dresden, Dresden, Germany
- German Center for Diabetes Research (DZD), Munich Neuherberg, Germany
| | - Raise Ahmad
- Inserm U1016, Institut Cochin, Paris, France
- CNRS UMR 8104, Paris, France
- Sorbonne Paris Cité, Univ. Paris Descartes, Paris, France
| | - Philippe Delagrange
- Pôle d'Innovation Thérapeutique Neuropsychiatrie, Institut de Recherches Servier, Croissy, France
| | - Michele Solimena
- Molecular Diabetology, Faculty of Medicine, University Hospital, TU Dresden, Dresden, Germany
- Faculty of Medicine, Paul Langerhans Institute Dresden (PLID) of the Helmholtz Center Munich at University Hospital Carl Gustav Carus, TU Dresden, Dresden, Germany
- German Center for Diabetes Research (DZD), Munich Neuherberg, Germany
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden, Germany
| | - Ralf Jockers
- Inserm U1016, Institut Cochin, Paris, France
- CNRS UMR 8104, Paris, France
- Sorbonne Paris Cité, Univ. Paris Descartes, Paris, France
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15
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Gautier C, Dufour E, Dupré C, Lizzo G, Caignard S, Riest-Fery I, Brasseur C, Legros C, Delagrange P, Nosjean O, Simonneaux V, Boutin JA, Guenin SP. Hamster Melatonin Receptors: Cloning and Binding Characterization of MT₁ and Attempt to Clone MT₂. Int J Mol Sci 2018; 19:E1957. [PMID: 29973510 PMCID: PMC6073278 DOI: 10.3390/ijms19071957] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 06/27/2018] [Accepted: 07/02/2018] [Indexed: 12/17/2022] Open
Abstract
For many years, it was of interest to identify the sequences encoding the two melatonin receptors (MT₁ and MT₂) from various species. After publishing the basic molecular characterization of the human, rat, mouse, sheep, and platypus MT₁, MT₂, or Mel1c receptors, we began cloning the genes from other animals, such as birds, bats, and vipers. The goal was to advance the receptor crystallization, which could greatly contribute the understanding of the sequence/stability relationship. European hamster MT₁ receptor was cloned for the first time from this gender, was expressed in stable form in cells, and its binding characterized with a sample of 19 melatonin ligands. Siberian hamster (Phodopus sungorus) expresses a non-functional MT₂. We observed that unlike this hamster, the European hamster (Cricetus cricetus) does not have a stop codon in the MT₂ sequence. Thus, we undertook the tedious task of cloning the MT₂ receptor. We partially succeeded, sequencing the complete exon 2 and a fragment of exon 1 (from putative amino acids 12 to 38 and 77 to 323), after several years of efforts. In order to show that the protein parts we cloned were capable to sustain some binding capacities, we designed a chimeric MT₂ receptor using a consensus sequence to replace the unknown amino acids, based on other small rodent MT₂ sequences. This chimeric construct could bind melatonin in the nanomolar range. This work is meant to be the basis for attempts from other laboratories of the community to determine the complete natural sequence of the European hamster MT₂ receptor. The present work is the first to show that, among the hamsters, if the Siberian is a natural knockout for MT₂, the European one is not.
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Affiliation(s)
- Célia Gautier
- PEX Biotechnologie Chimie & Biologie, Institut de Recherches Servier, 78290 Croissy sur Seine, France.
- Institut des Neurosciences Cellulaires et Intégratives, 67084 Strasbourg, France.
| | - Emilie Dufour
- PEX Biotechnologie Chimie & Biologie, Institut de Recherches Servier, 78290 Croissy sur Seine, France.
| | - Clémence Dupré
- PEX Biotechnologie Chimie & Biologie, Institut de Recherches Servier, 78290 Croissy sur Seine, France.
| | - Giulia Lizzo
- PEX Biotechnologie Chimie & Biologie, Institut de Recherches Servier, 78290 Croissy sur Seine, France.
| | - Sarah Caignard
- PEX Biotechnologie Chimie & Biologie, Institut de Recherches Servier, 78290 Croissy sur Seine, France.
| | - Isabelle Riest-Fery
- PEX Biotechnologie Chimie & Biologie, Institut de Recherches Servier, 78290 Croissy sur Seine, France.
| | - Chantal Brasseur
- PEX Biotechnologie Chimie & Biologie, Institut de Recherches Servier, 78290 Croissy sur Seine, France.
| | - Céline Legros
- PEX Biotechnologie Chimie & Biologie, Institut de Recherches Servier, 78290 Croissy sur Seine, France.
| | - Philippe Delagrange
- PEX Biotechnologie Chimie & Biologie, Institut de Recherches Servier, 78290 Croissy sur Seine, France.
| | - Olivier Nosjean
- PEX Biotechnologie Chimie & Biologie, Institut de Recherches Servier, 78290 Croissy sur Seine, France.
- Institut de Recherches Internationales Servier, 92150 Suresnes, France.
| | - Valérie Simonneaux
- Institut des Neurosciences Cellulaires et Intégratives, 67084 Strasbourg, France.
| | - Jean A Boutin
- PEX Biotechnologie Chimie & Biologie, Institut de Recherches Servier, 78290 Croissy sur Seine, France.
- Institut de Recherches Internationales Servier, 92150 Suresnes, France.
| | - Sophie-Pénélope Guenin
- PEX Biotechnologie Chimie & Biologie, Institut de Recherches Servier, 78290 Croissy sur Seine, France.
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16
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Gautier C, Guenin SP, Riest-Fery I, Perry TJ, Legros C, Nosjean O, Simonneaux V, Grützner F, Boutin JA. Characterization of the Mel1c melatoninergic receptor in platypus (Ornithorhynchus anatinus). PLoS One 2018. [PMID: 29529033 PMCID: PMC5846726 DOI: 10.1371/journal.pone.0191904] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Melatonin is a neurohormone produced in both animals and plants. It binds at least three G-protein-coupled receptors: MT1 and MT2, and Mel1cGPR. Mammalian GPR50 evolved from the reptilian/avian Mel1c and lost its capacity to bind melatonin in all the therian mammal species that have been tested. In order to determine if binding is lost in the oldest surviving mammalian lineage of monotremes we investigated whether the melatonin receptor has the ability to bind melatonin in the platypus (Ornithorhynchus anatinus), and evaluated its pharmacological profile. Sequence and phylogenetic analysis showed that platypus has in fact retained the ancestral Mel1c and has the capacity to bind melatonin similar to other mammalian melatonin receptors (MT1 and MT2), with an affinity in the 1 nM range. We also investigated the binding of a set of melatoninergic ligands used previously to characterize the molecular pharmacology of the melatonin receptors from sheep, rats, mice, and humans and found that the general profiles of these compounds make Mel1c resemble human MT1 more than MT2. This work shows that the loss of GPR50 binding evolved after the divergence of monotremes less than 190MYA in therian mammals.
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MESH Headings
- Animals
- Base Sequence
- COS Cells
- Chlorocebus aethiops
- Cloning, Molecular/methods
- Melatonin/metabolism
- Phylogeny
- Platypus/genetics
- Platypus/metabolism
- Protein Binding
- Receptor, Melatonin, MT1/chemistry
- Receptor, Melatonin, MT1/genetics
- Receptor, Melatonin, MT1/metabolism
- Receptor, Melatonin, MT2/chemistry
- Receptor, Melatonin, MT2/genetics
- Receptor, Melatonin, MT2/metabolism
- Receptors, Melatonin/chemistry
- Receptors, Melatonin/genetics
- Receptors, Melatonin/metabolism
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Affiliation(s)
- Célia Gautier
- PEX Biotechnologie Chimie & Biologie, Institut de Recherches Servier, Croissy sur Seine, France
- Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Sophie-Penelope Guenin
- PEX Biotechnologie Chimie & Biologie, Institut de Recherches Servier, Croissy sur Seine, France
| | - Isabelle Riest-Fery
- PEX Biotechnologie Chimie & Biologie, Institut de Recherches Servier, Croissy sur Seine, France
| | - Tahlia Jade Perry
- School of Biological Sciences, The University of Adelaide, Adelaide, Australia
| | - Céline Legros
- PEX Biotechnologie Chimie & Biologie, Institut de Recherches Servier, Croissy sur Seine, France
| | - Olivier Nosjean
- PEX Biotechnologie Chimie & Biologie, Institut de Recherches Servier, Croissy sur Seine, France
- Institut de Recherches Internationales Servier, Suresnes, France
| | - Valerie Simonneaux
- Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Frank Grützner
- School of Biological Sciences, The University of Adelaide, Adelaide, Australia
| | - Jean A. Boutin
- PEX Biotechnologie Chimie & Biologie, Institut de Recherches Servier, Croissy sur Seine, France
- Institut de Recherches Internationales Servier, Suresnes, France
- * E-mail:
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17
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Legros C, Brasseur C, Delagrange P, Ducrot P, Nosjean O, Boutin JA. Alternative Radioligands for Investigating the Molecular Pharmacology of Melatonin Receptors. J Pharmacol Exp Ther 2016; 356:681-92. [PMID: 26759496 DOI: 10.1124/jpet.115.229989] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Accepted: 01/11/2016] [Indexed: 12/15/2022] Open
Abstract
Melatonin exerts a variety of physiologic activities that are mainly relayed through the melatonin receptors MT1 and MT2 Low expressions of these receptors in tissues have led to widespread experimental use of the agonist 2-[(125)I]-iodomelatonin as a substitute for melatonin. We describe three iodinated ligands: 2-(2-[(2-iodo-4,5-dimethoxyphenyl)methyl]-4,5-dimethoxy phenyl) (DIV880) and (2-iodo-N-2-[5-methoxy-2-(naphthalen-1-yl)-1H-pyrrolo[3,2-b]pyridine-3-yl])acetamide (S70254), which are specific ligands at MT2 receptors, and N-[2-(5-methoxy-1H-indol-3-yl)ethyl]iodoacetamide (SD6), an analog of 2-[(125)I]-iodomelatonin with slightly different characteristics. Here, we further characterized these new ligands with regards to their molecular pharmacology. We performed binding experiments, saturation assays, association/dissociation rate measurements, and autoradiography using sheep and rat tissues and recombinant cell lines. Our results showed that [(125)I]-S70254 is receptor, and can be used with both cells and tissue. This radioligand can be used in autoradiography. Similarly, DIV880, a partial agonist [43% of melatonin on guanosine 5'-3-O-(thio)triphosphate binding assay], selective for MT2, can be used as a tool to selectively describe the pharmacology of this receptor in tissue samples. The molecular pharmacology of both human melatonin receptors MT1 and MT2, using a series of 24 ligands at these receptors and the new radioligands, did not lead to noticeable variations in the profiles. For the first time, we described radiolabeled tools that are specific for one of the melatonin receptors (MT2). These tools are amenable to binding experiments and to autoradiography using sheep or rat tissues. These specific tools will permit better understanding of the role and implication in physiopathologic processes of the melatonin receptors.
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Affiliation(s)
- Céline Legros
- Pôle d'Expertise Biotechnologie, Chimie, Biologie (C.L., C.B., P.Du., O.N., J.A.B.), and Unité de Recherches et Découvertes en Neurosciences (P.De.), Institut de Recherches SERVIER, Croissy-sur-Seine, France
| | - Chantal Brasseur
- Pôle d'Expertise Biotechnologie, Chimie, Biologie (C.L., C.B., P.Du., O.N., J.A.B.), and Unité de Recherches et Découvertes en Neurosciences (P.De.), Institut de Recherches SERVIER, Croissy-sur-Seine, France
| | - Philippe Delagrange
- Pôle d'Expertise Biotechnologie, Chimie, Biologie (C.L., C.B., P.Du., O.N., J.A.B.), and Unité de Recherches et Découvertes en Neurosciences (P.De.), Institut de Recherches SERVIER, Croissy-sur-Seine, France
| | - Pierre Ducrot
- Pôle d'Expertise Biotechnologie, Chimie, Biologie (C.L., C.B., P.Du., O.N., J.A.B.), and Unité de Recherches et Découvertes en Neurosciences (P.De.), Institut de Recherches SERVIER, Croissy-sur-Seine, France
| | - Olivier Nosjean
- Pôle d'Expertise Biotechnologie, Chimie, Biologie (C.L., C.B., P.Du., O.N., J.A.B.), and Unité de Recherches et Découvertes en Neurosciences (P.De.), Institut de Recherches SERVIER, Croissy-sur-Seine, France
| | - Jean A Boutin
- Pôle d'Expertise Biotechnologie, Chimie, Biologie (C.L., C.B., P.Du., O.N., J.A.B.), and Unité de Recherches et Découvertes en Neurosciences (P.De.), Institut de Recherches SERVIER, Croissy-sur-Seine, France
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18
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Cordeiro N, Wijkhuisen A, Savatier A, Moulharat N, Ferry G, Léonetti M. Obtaining anti-type 1 melatonin receptor antibodies by immunization with melatonin receptor-expressing cells. J Immunol Methods 2015; 428:37-41. [PMID: 26657944 DOI: 10.1016/j.jim.2015.11.011] [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: 07/29/2015] [Revised: 11/25/2015] [Accepted: 11/30/2015] [Indexed: 11/25/2022]
Abstract
Antibodies (Abs) specific to cell-surface receptors are attractive tools for studying the physiological role of such receptors or for controlling their activity. We sought to obtain such antibodies against the type 1 receptor for melatonin (MT1). For this, we injected mice with CHO cells transfected with a plasmid encoding human MT1 (CHO-MT1-h), in the presence or absence of an adjuvant mixture containing Alum and CpG1018. As we previously observed that the immune response to a protein antigen is increased when it is coupled to a fusion protein, called ZZTat101, we also investigated if the association of ZZTat101 with CHO-MT1-h cells provides an immunogenic advantage. We measured similar levels of anti-CHO and anti-MT1-h Ab responses in animals injected with either CHO-MT1-h cells or ZZTat101/CHO-MT1-h cells, with or without adjuvant, indicating that neither the adjuvant mixture nor ZZTat101 increased the anti-cell immune response. Then, we investigated whether the antisera also recognized murine MT1 (MT1-m). Using cloned CHO cells transfected with a plasmid encoding MT1-m, we found that antisera raised against CHO-MT1-h cells also bound the mouse receptor. Altogether our studies indicate that immunizing approaches based on MT1-h-expressing CHO cells allow the production of polyclonal antibodies against MT1 receptors of different origins. This paves the way to preparation of MT1-specific monoclonal antibodies.
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Affiliation(s)
- Nelia Cordeiro
- CEA, institut de Biologie et de Technologie de Saclay (iBiTec-S), Service de Pharmacologie et d'immunoanalyse (SPI), 91191 Gif sur Yvette, France
| | | | - Alexandra Savatier
- CEA, institut de Biologie et de Technologie de Saclay (iBiTec-S), Service de Pharmacologie et d'immunoanalyse (SPI), 91191 Gif sur Yvette, France
| | - Natacha Moulharat
- Institut de Recherches Servier, Division Biotechnologie, Pharmacologie Moléculaire et Cellulaire, 125 Chemin de Ronde, 78290 Croissy-Sur-Seine, France
| | - Gilles Ferry
- Institut de Recherches Servier, Division Biotechnologie, Pharmacologie Moléculaire et Cellulaire, 125 Chemin de Ronde, 78290 Croissy-Sur-Seine, France
| | - Michel Léonetti
- CEA, institut de Biologie et de Technologie de Saclay (iBiTec-S), Service de Pharmacologie et d'immunoanalyse (SPI), 91191 Gif sur Yvette, France.
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19
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Liu J, Clough SJ, Hutchinson AJ, Adamah-Biassi EB, Popovska-Gorevski M, Dubocovich ML. MT1 and MT2 Melatonin Receptors: A Therapeutic Perspective. Annu Rev Pharmacol Toxicol 2015; 56:361-83. [PMID: 26514204 PMCID: PMC5091650 DOI: 10.1146/annurev-pharmtox-010814-124742] [Citation(s) in RCA: 367] [Impact Index Per Article: 40.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Melatonin, or 5-methoxy-N-acetyltryptamine, is synthesized and released by the pineal gland and locally in the retina following a circadian rhythm, with low levels during the day and elevated levels at night. Melatonin activates two high-affinity G protein-coupled receptors, termed MT1 and MT2, to exert beneficial actions in sleep and circadian abnormality, mood disorders, learning and memory, neuroprotection, drug abuse, and cancer. Progress in understanding the role of melatonin receptors in the modulation of sleep and circadian rhythms has led to the discovery of a novel class of melatonin agonists for treating insomnia, circadian rhythms, mood disorders, and cancer. This review describes the pharmacological properties of a slow-release melatonin preparation (i.e., Circadin®) and synthetic ligands (i.e., agomelatine, ramelteon, tasimelteon), with emphasis on identifying specific therapeutic effects mediated through MT1 and MT2 receptor activation. Discovery of selective ligands targeting the MT1 or the MT2 melatonin receptors may promote the development of novel and more efficacious therapeutic agents.
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Affiliation(s)
- Jiabei Liu
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, New York 14214; , , , , ,
| | - Shannon J Clough
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, New York 14214; , , , , ,
| | - Anthony J Hutchinson
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, New York 14214; , , , , ,
| | - Ekue B Adamah-Biassi
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, New York 14214; , , , , ,
| | - Marina Popovska-Gorevski
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, New York 14214; , , , , ,
| | - Margarita L Dubocovich
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, New York 14214; , , , , ,
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20
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Boutin JA. Quinone reductase 2 as a promising target of melatonin therapeutic actions. Expert Opin Ther Targets 2015; 20:303-17. [DOI: 10.1517/14728222.2016.1091882] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Jean A Boutin
- Institut de Recherches SERVIER, Pole d’Expertise Biotechnologie, Chimie & Biologie, 125, chemin de Ronde, 78290 Croissy-sur-Seine, France
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21
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In vitro comparison of duration of action of melatonin agonists on melatonin MT1 receptor: possible link between duration of action and dissociation rate from receptor. Eur J Pharmacol 2015; 757:42-52. [PMID: 25797281 DOI: 10.1016/j.ejphar.2015.03.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 02/03/2015] [Accepted: 03/01/2015] [Indexed: 12/15/2022]
Abstract
Melatonin MT1 and MT2 receptors are Gi protein-coupled receptors and promising therapeutic targets for a number of diseases. A proportion of G protein-coupled receptor agonists and antagonists have been classified according to their duration of action, which influences their pharmacological efficacy. However, the duration of action of melatonin agonists remains unclear. In this study, we investigated the duration of action of melatonin agonists (melatonin, 2-iodomelatonin, ramelteon, and the ramelteon metabolite M-II) at the melatonin MT1 receptor, which is more resistant to agonist-induced desensitization than the melatonin MT2 receptor. In Chinese hamster ovary cells stably expressing the human melatonin MT1 receptor, significant differences in the duration of action were observed after 2-h pretreatment with agonists followed by washout. In contrast to melatonin and M-II, the agonist activities of ramelteon and 2-iodomelatonin were persistent (i.e. inhibition of forskolin-stimulated cAMP formation and increase in ERK 1/2 phosphorylation) even after repeated washouts. Similar activities were observed for INS-1 cells endogenously expressing the rat MT1 receptor. Further, we examined potential factors linked to the duration of action. Residual activities of melatonin agonists after washout strongly correlated with their dissociation rates from the human melatonin MT1 receptor, but not their lipophilicity or extent of desensitization. These data suggest that the in vitro duration of action significantly differs between melatonin agonists and might dictate dissociation kinetics. Characterization of these in vitro properties may facilitate further in vivo study of the duration of action.
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Tosini G, Owino S, Guillaume JL, Jockers R. Understanding melatonin receptor pharmacology: latest insights from mouse models, and their relevance to human disease. Bioessays 2014; 36:778-87. [PMID: 24903552 PMCID: PMC4151498 DOI: 10.1002/bies.201400017] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Melatonin, the neuro-hormone synthesized during the night, has recently seen an unexpected extension of its functional implications toward type 2 diabetes development, visual functions, sleep disturbances, and depression. Transgenic mouse models were instrumental for the establishment of the link between melatonin and these major human diseases. Most of the actions of melatonin are mediated by two types of G protein-coupled receptors, named MT1 and MT2 , which are expressed in many different organs and tissues. Understanding the pharmacology and function of mouse MT1 and MT2 receptors, including MT1 /MT2 heteromers, will be of crucial importance to evaluate the relevance of these mouse models for future therapeutic developments. This review will critically discuss these aspects, and give some perspectives including the generation of new mouse models.
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Affiliation(s)
- Gianluca Tosini
- Neuroscience Institute and Department of Pharmacology and Toxicology, Morehouse School of Medicine, Atlanta, GA, USA
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23
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Logez C, Berger S, Legros C, Banères JL, Cohen W, Delagrange P, Nosjean O, Boutin JA, Ferry G, Simonin F, Wagner R. Recombinant human melatonin receptor MT1 isolated in mixed detergents shows pharmacology similar to that in mammalian cell membranes. PLoS One 2014; 9:e100616. [PMID: 24959712 PMCID: PMC4069108 DOI: 10.1371/journal.pone.0100616] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Accepted: 05/27/2014] [Indexed: 01/08/2023] Open
Abstract
The human melatonin MT1 receptor—belonging to the large family of G protein-coupled receptors (GPCRs)—plays a key role in circadian rhythm regulation and is notably involved in sleep disorders and depression. Structural and functional information at the molecular level are highly desired for fine characterization of this receptor; however, adequate techniques for isolating soluble MT1 material suitable for biochemical and biophysical studies remain lacking. Here we describe the evaluation of a panel of constructs and host systems for the production of recombinant human MT1 receptors, and the screening of different conditions for their solubilization and purification. Our findings resulted in the establishment of an original strategy using a mixture of Fos14 and CHAPS detergents to extract and purify a recombinant human MT1 from Pichia pastoris membranes. This procedure enabled the recovery of relatively pure, monomeric and ligand-binding active MT1 receptor in the near-milligram range. A comparative study based on extensive ligand-binding characterization highlighted a very close correlation between the pharmacological profiles of MT1 purified from yeast and the same receptor present in mammalian cell membranes. The high quality of the purified MT1 was further confirmed by its ability to activate its cognate Gαi protein partner when reconstituted in lipid discs, thus opening novel paths to investigate this receptor by biochemical and biophysical approaches.
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Affiliation(s)
- Christel Logez
- CNRS UMR7242/Laboratoire d'excellence MEDALIS, Institut de Recherche de l'ESBS, Biotechnologie et Signalisation Cellulaire, Université de Strasbourg, Illkirch, France
- Biotechnologie, Pharmacologie Moléculaire et Cellulaire, Institut de Recherches Servier, Croissy-sur-Seine, France
| | - Sylvie Berger
- Biotechnologie, Pharmacologie Moléculaire et Cellulaire, Institut de Recherches Servier, Croissy-sur-Seine, France
| | - Céline Legros
- Biotechnologie, Pharmacologie Moléculaire et Cellulaire, Institut de Recherches Servier, Croissy-sur-Seine, France
| | - Jean-Louis Banères
- CNRS UMR 5247, Institut des Biomolécules Max Mousseron (IBMM), Université de Montpellier 1 and Montpellier 2, Faculté de Pharmacie, Montpellier, France
| | - William Cohen
- Biotechnologie, Pharmacologie Moléculaire et Cellulaire, Institut de Recherches Servier, Croissy-sur-Seine, France
| | - Philippe Delagrange
- Unité de Recherches et Découvertes en Neurosciences, Institut de Recherche Servier, Croissy-sur-Seine, France
| | - Olivier Nosjean
- Biotechnologie, Pharmacologie Moléculaire et Cellulaire, Institut de Recherches Servier, Croissy-sur-Seine, France
| | - Jean A. Boutin
- Biotechnologie, Pharmacologie Moléculaire et Cellulaire, Institut de Recherches Servier, Croissy-sur-Seine, France
- * E-mail:
| | - Gilles Ferry
- Biotechnologie, Pharmacologie Moléculaire et Cellulaire, Institut de Recherches Servier, Croissy-sur-Seine, France
| | - Frédéric Simonin
- CNRS UMR7242/Laboratoire d'excellence MEDALIS, Institut de Recherche de l'ESBS, Biotechnologie et Signalisation Cellulaire, Université de Strasbourg, Illkirch, France
| | - Renaud Wagner
- CNRS UMR7242/Laboratoire d'excellence MEDALIS, Institut de Recherche de l'ESBS, Biotechnologie et Signalisation Cellulaire, Université de Strasbourg, Illkirch, France
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24
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Legros C, Devavry S, Caignard S, Tessier C, Delagrange P, Ouvry C, Boutin JA, Nosjean O. Melatonin MT₁ and MT₂ receptors display different molecular pharmacologies only in the G-protein coupled state. Br J Pharmacol 2014; 171:186-201. [PMID: 24117008 PMCID: PMC3874706 DOI: 10.1111/bph.12457] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Revised: 09/13/2013] [Accepted: 09/18/2013] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND AND PURPOSE Melatonin receptors have been extensively characterized regarding their affinity and pharmacology, mostly using 2-[(125)I]-melatonin as a radioligand. Although [(3)H]-melatonin has the advantage of corresponding to the endogenous ligand of the receptor, its binding has not been well described. EXPERIMENTAL APPROACH We characterized [(3)H]-melatonin binding to the hMT₁ and hMT₂ receptors expressed in a range of cell lines and obtained new insights into the molecular pharmacology of melatonin receptors. KEY RESULTS The binding of [(3)H]-melatonin to the hMT₁ and hMT₂ receptors displayed two sites on the saturation curves. These two binding sites were observed on cell membranes expressing recombinant receptors from various species as well as on whole cells. Furthermore, our GTPγS/NaCl results suggest that these sites on the saturation curves correspond to the G-protein coupled and uncoupled states of the receptors, whose pharmacology was extensively characterized. CONCLUSIONS AND IMPLICATIONS hMT₁ and hMT₂ receptors spontaneously exist in two states when expressed in cell lines; these states can be probed by [(3)H]-melatonin binding. Overall, our results suggest that physiological regulation of the melatonin receptors may result from complex and subtle mechanisms, a small difference in affinity between the active and inactive states of the receptor, and spontaneous coupling to G-proteins.
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Affiliation(s)
- Céline Legros
- Biotechnologies, Pharmacologie Moléculaire et Cellulaire, Institut de Recherches ServierCroissy-sur-Seine, France
| | - Séverine Devavry
- Biotechnologies, Pharmacologie Moléculaire et Cellulaire, Institut de Recherches ServierCroissy-sur-Seine, France
- INRA, UMR85 Physiologie de la Reproduction et des ComportementsNouzilly, France
- CNRS, UMR6175Nouzilly, France
| | - Sarah Caignard
- Biotechnologies, Pharmacologie Moléculaire et Cellulaire, Institut de Recherches ServierCroissy-sur-Seine, France
| | - Clémence Tessier
- Biotechnologies, Pharmacologie Moléculaire et Cellulaire, Institut de Recherches ServierCroissy-sur-Seine, France
| | - Philippe Delagrange
- Unité de Recherches en Neurosciences, Institut de Recherches ServierCroissy-sur-Seine, France
| | - Christine Ouvry
- Biotechnologies, Pharmacologie Moléculaire et Cellulaire, Institut de Recherches ServierCroissy-sur-Seine, France
| | - Jean A Boutin
- Biotechnologies, Pharmacologie Moléculaire et Cellulaire, Institut de Recherches ServierCroissy-sur-Seine, France
| | - Olivier Nosjean
- Biotechnologies, Pharmacologie Moléculaire et Cellulaire, Institut de Recherches ServierCroissy-sur-Seine, France
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25
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Devavry S, Legros C, Brasseur C, Delagrange P, Spadoni G, Cohen W, Malpaux B, Boutin JA, Nosjean O. Description of the constitutive activity of cloned human melatonin receptors hMT(1) and hMT(2) and discovery of inverse agonists. J Pineal Res 2012; 53:29-37. [PMID: 22017484 DOI: 10.1111/j.1600-079x.2011.00968.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Melatonin receptors have been described to activate different G protein-dependent signaling pathways, both in laboratory, heterologous, cellular models and in physiological conditions. Furthermore, the constitutive activity of G protein-coupled receptors has been shown to be key in physiological and pathological conditions. In the case of melatonin receptors, information is rather scare and concerns only MT1 receptors. In the present report, we show that the G protein-coupled melatonin receptors do have a constitutive, nonmelatonin-induced signaling activity using two cellular models of different origins, the Chinese hamster ovary cell line and Neuro2A, a neuroblastoma cell line. Furthermore, we show that this constitutive activity involves mainly Gi proteins, which is consistent with the common knowledge on the melatonin receptors. Importantly, we also describe, for the first time, inverse agonist properties for melatonin ligands. Although it is clear than more in-depth, biochemistry-based studies will be required to better understand by which pathway(s) the constitutively active melatonin receptors transfer melatonin information into intracellular biochemical events; our data open interesting perspectives for understanding the importance of the constitutive activity of melatonin receptors in physiological conditions.
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MESH Headings
- Animals
- CHO Cells
- Cloning, Molecular
- Cricetinae
- Cricetulus
- GTP-Binding Protein alpha Subunits, Gi-Go/genetics
- GTP-Binding Protein alpha Subunits, Gi-Go/metabolism
- Humans
- Melatonin/metabolism
- Receptor, Melatonin, MT1/agonists
- Receptor, Melatonin, MT1/genetics
- Receptor, Melatonin, MT1/metabolism
- Receptor, Melatonin, MT2/agonists
- Receptor, Melatonin, MT2/genetics
- Receptor, Melatonin, MT2/metabolism
- Signal Transduction/physiology
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Affiliation(s)
- Séverine Devavry
- INRA, UMR85 Physiologie de la Reproduction et des Comportements, Nouzilly, France
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26
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Devavry S, Legros C, Brasseur C, Cohen W, Guenin SP, Delagrange P, Malpaux B, Ouvry C, Cogé F, Nosjean O, Boutin JA. Molecular pharmacology of the mouse melatonin receptors MT₁ and MT₂. Eur J Pharmacol 2011; 677:15-21. [PMID: 22202844 DOI: 10.1016/j.ejphar.2011.12.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Revised: 11/29/2011] [Accepted: 12/07/2011] [Indexed: 12/15/2022]
Abstract
The main melatonin receptors are two G-protein coupled receptors named MT(1) and MT(2). Having described the molecular pharmacology of the human versions of these receptors, we turned to two of the three species most useful in studying melatonin physiology: rat and sheep (a diurnal species used to understand the relationship between circadian rhythm and depression). We also employed previously used compounds to describe the mouse melatonin receptors; despite the early cloning of mouse receptors, few molecular pharmacology studies on these receptors exist. To our surprise, we detected no major differences between the data obtained from mice and those from other species.
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Affiliation(s)
- Séverine Devavry
- INRA, UMR85 Physiologie de Reproduction et des Comportements, F-37380 Nouzilly, France
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27
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Dubocovich ML, Delagrange P, Krause DN, Sugden D, Cardinali DP, Olcese J. International Union of Basic and Clinical Pharmacology. LXXV. Nomenclature, classification, and pharmacology of G protein-coupled melatonin receptors. Pharmacol Rev 2010; 62:343-80. [PMID: 20605968 PMCID: PMC2964901 DOI: 10.1124/pr.110.002832] [Citation(s) in RCA: 392] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The hormone melatonin (5-methoxy-N-acetyltryptamine) is synthesized primarily in the pineal gland and retina, and in several peripheral tissues and organs. In the circulation, the concentration of melatonin follows a circadian rhythm, with high levels at night providing timing cues to target tissues endowed with melatonin receptors. Melatonin receptors receive and translate melatonin's message to influence daily and seasonal rhythms of physiology and behavior. The melatonin message is translated through activation of two G protein-coupled receptors, MT(1) and MT(2), that are potential therapeutic targets in disorders ranging from insomnia and circadian sleep disorders to depression, cardiovascular diseases, and cancer. This review summarizes the steps taken since melatonin's discovery by Aaron Lerner in 1958 to functionally characterize, clone, and localize receptors in mammalian tissues. The pharmacological and molecular properties of the receptors are described as well as current efforts to discover and develop ligands for treatment of a number of illnesses, including sleep disorders, depression, and cancer.
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Affiliation(s)
- Margarita L Dubocovich
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, University at Buffalo State University of New York, 3435 Main Street, Buffalo, NY 14214, USA.
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28
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Konturek PC, Konturek SJ, Celinski K, Slomka M, Cichoz-Lach H, Bielanski W, Reiter RJ. Role of melatonin in mucosal gastroprotection against aspirin-induced gastric lesions in humans. J Pineal Res 2010; 48:318-23. [PMID: 20443220 DOI: 10.1111/j.1600-079x.2010.00755.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Melatonin and its precursor, l-tryptophan, have been shown to exert gastroprotective effects in animals, but their influence on the gastric damage by aspirin (ASA) in humans has been sparingly investigated. In this study, we designed to determine the effects of melatonin and l-tryptophan on ASA-induced gastric mucosal damage, gastric microbleeding, mucosal generation of prostaglandin E(2), and plasma melatonin, and gastrin levels. Three groups of healthy male volunteers (n = 30) with intact gastric mucosa received daily for 11 days either ASA alone or that combined with melatonin or tryptophan. Gastric blood loss and mucosal damage were evaluated at 3rd, 7th, and 11th days of ASA administration by endoscopy using Lanza score. ASA alone caused a marked rise of gastric damage and gastric blood loss, mainly at day 3rd and 7th, but they were significantly reduced at 11th day. Pretreatment with melatonin or tryptophan remarkably reduced ASA induced gastric lesions and microbleeding. Gastric mucosal generation of PGE(2) was suppressed by about 90% in all subjects treated with ASA alone without or with addition of melatonin or tryptophan. Plasma melatonin was markedly increased after treatment with melatonin or tryptophan plus ASA, but it was also raised significantly after application of ASA alone. Plasma gastrin levels were raised in subjects given melatonin or tryptophan plus ASA, but not in those with ASA alone. We conclude that melatonin and its precursor tryptophan given orally significantly reduce gastric lesions induced by ASA possibly due to (a) direct gastroprotective action of exogenous melatonin or that generated from tryptophan and (b) gastrin released from the gastric mucosa by melatonin or tryptophan.
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Affiliation(s)
- P C Konturek
- Department of Medicine, Thuringia Clinic Georgius Agricola Saalfeld, Teaching Hospital, Gemany
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29
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Tong Z, Luo W, Wang Y, Yang F, Han Y, Li H, Luo H, Duan B, Xu T, Maoying Q, Tan H, Wang J, Zhao H, Liu F, Wan Y. Tumor tissue-derived formaldehyde and acidic microenvironment synergistically induce bone cancer pain. PLoS One 2010; 5:e10234. [PMID: 20422007 PMCID: PMC2858155 DOI: 10.1371/journal.pone.0010234] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2009] [Accepted: 03/24/2010] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND There is current interest in understanding the molecular mechanisms of tumor-induced bone pain. Accumulated evidence shows that endogenous formaldehyde concentrations are elevated in the blood or urine of patients with breast, prostate or bladder cancer. These cancers are frequently associated with cancer pain especially after bone metastasis. It is well known that transient receptor potential vanilloid receptor 1 (TRPV1) participates in cancer pain. The present study aims to demonstrate that the tumor tissue-derived endogenous formaldehyde induces bone cancer pain via TRPV1 activation under tumor acidic environment. METHODOLOGY/PRINCIPAL FINDINGS Endogenous formaldehyde concentration increased significantly in the cultured breast cancer cell lines in vitro, in the bone marrow of breast MRMT-1 bone cancer pain model in rats and in tissues from breast cancer and lung cancer patients in vivo. Low concentrations (1 approximately 5 mM) of formaldehyde induced pain responses in rat via TRPV1 and this pain response could be significantly enhanced by pH 6.0 (mimicking the acidic tumor microenvironment). Formaldehyde at low concentrations (1 mM to 100 mM) induced a concentration-dependent increase of [Ca(2+)]i in the freshly isolated rat dorsal root ganglion neurons and TRPV1-transfected CHO cells. Furthermore, electrophysiological experiments showed that low concentration formaldehyde-elicited TRPV1 currents could be significantly potentiated by low pH (6.0). TRPV1 antagonists and formaldehyde scavengers attenuated bone cancer pain responses. CONCLUSIONS/SIGNIFICANCE Our data suggest that cancer tissues directly secrete endogenous formaldehyde, and this formaldehyde at low concentration induces metastatic bone cancer pain through TRPV1 activation especially under tumor acidic environment.
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Affiliation(s)
- Zhiqian Tong
- Neuroscience Research Institute, Peking University, Beijing, China
- * E-mail: (ZT); (YW)
| | - Wenhong Luo
- The Central Laboratory, Shantou University Medical College, Shantou, China
| | - Yanqing Wang
- Department of Integrative Medicine and Neurobiology, State Key Laboratory of Medical Neurobiology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Fei Yang
- Neuroscience Research Institute, Peking University, Beijing, China
| | - Ying Han
- Neuroscience Research Institute, Peking University, Beijing, China
| | - Hui Li
- The Central Laboratory, Shantou University Medical College, Shantou, China
| | - Hongjun Luo
- The Central Laboratory, Shantou University Medical College, Shantou, China
| | - Bo Duan
- Institute of Neuroscience and National Key Laboratory of Neuroscience, Chinese Academy of Sciences, Shanghai, China
| | - Tianle Xu
- Institute of Neuroscience and National Key Laboratory of Neuroscience, Chinese Academy of Sciences, Shanghai, China
| | - Qiliang Maoying
- Department of Integrative Medicine and Neurobiology, State Key Laboratory of Medical Neurobiology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Huangying Tan
- Department of TCM Oncology, China-Japan Friendship Hospital, Beijing, China
| | - Jun Wang
- Department of Thoratic Surgery, Peking University People's Hospital, Beijing, China
| | - Hongmei Zhao
- Department of General Surgery, Peking University Third Hospital, Beijing, China
| | - Fengyu Liu
- Neuroscience Research Institute, Peking University, Beijing, China
| | - You Wan
- Neuroscience Research Institute, Peking University, Beijing, China
- Key Laboratory for Neuroscience, Ministry of Education/Ministry of Public Health, Beijing, China
- * E-mail: (ZT); (YW)
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30
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Srinivasan V, Pandi-Perumal SR, Spence DW, Moscovitch A, Trakht I, Brown GM, Cardinali DP. Potential use of melatonergic drugs in analgesia: mechanisms of action. Brain Res Bull 2010; 81:362-71. [PMID: 20005925 DOI: 10.1016/j.brainresbull.2009.12.001] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2009] [Revised: 12/01/2009] [Accepted: 12/02/2009] [Indexed: 12/12/2022]
Abstract
Melatonin is a remarkable molecule with diverse physiological functions. Some of its effects are mediated by receptors while other, like cytoprotection, seem to depend on direct and indirect scavenging of free radicals not involving receptors. Among melatonin's many effects, its antinociceptive actions have attracted attention. When given orally, intraperitoneally, locally, intrathecally or through intracerebroventricular routes, melatonin exerts antinociceptive and antiallodynic actions in a variety of animal models. These effects have been demonstrated in animal models of acute pain like the tail-flick test, formalin test or endotoxin-induced hyperalgesia as well as in models of neuropathic pain like nerve ligation. Glutamate, gamma-aminobutyric acid, and particularly, opioid neurotransmission have been demonstrated to be involved in melatonin's analgesia. Results using melatonin receptor antagonists support the participation of melatonin receptors in melatonin's analgesia. However, discrepancies between the affinity of the receptors and the very high doses of melatonin needed to cause effects in vivo raise doubts about the uniqueness of that physiopathological interpretation. Indeed, melatonin could play a role in pain through several alternative mechanisms including free radicals scavenging or nitric oxide synthase inhibition. The use of melatonin analogs like the MT(1)/MT(2) agonist ramelteon, which lacks free radical scavenging activity, could be useful to unravel the mechanism of action of melatonin in analgesia. Melatonin has a promising role as an analgesic drug that could be used for alleviating pain associated with cancer, headache or surgical procedures.
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31
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Srinivasan V, Spence DW, Moscovitch A, Pandi-Perumal SR, Trakht I, Brown GM, Cardinali DP. Malaria: therapeutic implications of melatonin. J Pineal Res 2010; 48:1-8. [PMID: 20025640 DOI: 10.1111/j.1600-079x.2009.00728.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Malaria, which infects more than 300 million people annually, is a serious disease. Epidemiological surveys indicate that of those who are affected, malaria will claim the lives of more than one million individuals, mostly children. There is evidence that the synchronous maturation of Plasmodium falciparum, the parasite that causes a severe form of malaria in humans and Plasmodium chabaudi, responsible for rodent malaria, could be linked to circadian changes in melatonin concentration. In vitro melatonin stimulates the growth and development of P. falciparum through the activation of specific melatonin receptors coupled to phospholipase-C activation and the concomitant increase of intracellular Ca2+. The Ca2+ signaling pathway is important to stimulate parasite transition from the trophozoite to the schizont stage, the final stage of intraerythrocytic cycle, thus promoting the rise of parasitemia. Either pinealectomy or the administration of the melatonin receptor blocking agent luzindole desynchronizes the parasitic cell cycle. Therefore, the use of melatonin antagonists could be a novel therapeutic approach for controlling the disease. On the other hand, the complexity of melatonin's action in malaria is underscored by the demonstration that treatment with high doses of melatonin is actually beneficial for inhibiting apoptosis and liver damage resulting from the oxidative stress in malaria. The possibility that the coordinated administration of melatonin antagonists (to impair the melatonin signal that synchronizes P. falciparum) and of melatonin in doses high enough to decrease oxidative damage could be a novel approach in malaria treatment is discussed.
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32
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Cogé F, Guenin SP, Fery I, Migaud M, Devavry S, Slugocki C, Legros C, Ouvry C, Cohen W, Renault N, Nosjean O, Malpaux B, Delagrange P, Boutin JA. The end of a myth: cloning and characterization of the ovine melatonin MT(2) receptor. Br J Pharmacol 2009; 158:1248-62. [PMID: 19814723 DOI: 10.1111/j.1476-5381.2009.00453.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND AND PURPOSE For many years, it was suspected that sheep expressed only one melatonin receptor (closely resembling MT(1) from other mammal species). Here we report the cloning of another melatonin receptor, MT(2), from sheep. EXPERIMENTAL APPROACH Using a thermo-resistant reverse transcriptase and polymerase chain reaction primer set homologous to the bovine MT(2) mRNA sequence, we have cloned and characterized MT(2) receptors from sheep retina. KEY RESULTS The ovine MT(2) receptor presents 96%, 72% and 67% identity with cattle, human and rat respectively. This MT(2) receptor stably expressed in CHO-K1 cells showed high-affinity 2[(125)I]-iodomelatonin binding (K(D)= 0.04 nM). The rank order of inhibition of 2[(125)I]-iodomelatonin binding by melatonin, 4-phenyl-2-propionamidotetralin and luzindole was similar to that exhibited by MT(2) receptors of other species (melatonin > 4-phenyl-2-propionamidotetralin > luzindole). However, its pharmacological profile was closer to that of rat, rather than human MT(2) receptors. Functionally, the ovine MT(2) receptors were coupled to G(i) proteins leading to inhibition of adenylyl cyclase, as the other melatonin receptors. In sheep brain, MT(2) mRNA was expressed in pars tuberalis, choroid plexus and retina, and moderately in mammillary bodies. Real-time polymerase chain reaction showed that in sheep pars tuberalis, premammillary hypothalamus and mammillary bodies, the temporal pattern of expression of MT(1) and MT(2) mRNA was not parallel in the three tissues. CONCLUSION AND IMPLICATIONS Co-expression of MT(1) and MT(2) receptors in all analysed sheep brain tissues suggests that MT(2) receptors may participate in melatonin regulation of seasonal anovulatory activity in ewes by modulating MT(1) receptor action.
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Affiliation(s)
- F Cogé
- Pharmacologie Moléculaire et Cellulaire, Institut de Recherches SERVIER, Suresnes, France
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Rivara S, Vacondio F, Fioni A, Silva C, Carmi C, Mor M, Lucini V, Pannacci M, Caronno A, Scaglione F, Gobbi G, Spadoni G, Bedini A, Orlando P, Lucarini S, Tarzia G. N-(Anilinoethyl)amides: Design and Synthesis of Metabolically Stable, Selective Melatonin Receptor Ligands. ChemMedChem 2009; 4:1746-55. [DOI: 10.1002/cmdc.200900240] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Alarma-Estrany P, Crooke A, Pintor J. 5-MCA-NAT does not act through NQO2 to reduce intraocular pressure in New-Zealand white rabbit. J Pineal Res 2009; 47:201-209. [PMID: 19627460 DOI: 10.1111/j.1600-079x.2009.00702.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Solid data support the idea that the MT(3) melatonin binding site is an enzyme, quinone reductase 2 (NQO2), rather than a membrane melatonin receptor. However, the melatonin analogue, 5-methoxycarbonylamino-N-acetyltryptamine (5-MCA-NAT), reduces intraocular pressure (IOP) via MT(3) melatonin receptors. Therefore, the aim of this work was to test whether the melatonin binding site, MT(3), is indeed the enzyme NQO2 in New Zealand rabbit eyes. To investigate this, the action of several substrates and inhibitors for NQO2 was compared to 5-MCA-NAT in their ability to modify IOP. Also, the effect of 5-MCA-NAT on IOP produced after NQO2 silencing by means of a siRNA was determinated. Altogether, the results led us to conclude that the in vivo effect of the MT(3) ligand 5-MCA-NAT on IOP is not mediated by the enzyme NQO2, suggesting the existence of another melatonin receptor.
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Affiliation(s)
| | | | - Jesús Pintor
- Departamento Bioquímica, E.U. Óptica, Universidad Complutense de Madrid, C/Arcos de Jalón s/n, Madrid, Spain
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Nishiyama K, Shintani Y, Hirai K, Yoshikubo SI. Molecular cloning and pharmacological characterization of monkey MT1 and MT2 melatonin receptors showing high affinity for the agonist ramelteon. J Pharmacol Exp Ther 2009; 330:855-63. [PMID: 19556449 DOI: 10.1124/jpet.109.155283] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Melatonin receptor agonists such as melatonin and ramelteon [(S)-N-[2-(1,6,7,8-tetrahydro-2H-indeno-[5,4-b]furan-8-yl)ethyl]-propionamide; TAK-375] have sleep-promoting effects in humans. In preclinical models, these effects are more similar to those observed in monkeys than in other species. However, in contrast to the human melatonin receptors, the pharmacological characteristics of the monkey melatonin receptors have yet to be elucidated. In this study, we cloned the cynomolgus monkey MT(1) and MT(2) melatonin receptors based on rhesus monkey genome sequences and then characterized the monkey melatonin receptors and compared their pharmacological properties with those of the human homologs. The overall amino acid sequences of the monkey MT(1) and MT(2) melatonin receptors showed high homology to the human MT(1) (95%) and MT(2) (96%) receptors, respectively. Saturation binding experiments with 2-[(125)I]iodomelatonin revealed that the dissociation constants (K(d)) for the monkey MT(1) and MT(2) melatonin receptors were 19.9 and 70.4 pM, respectively. In ligand competition assays using 2-[(125)I]iodomelatonin, ramelteon displayed approximately 3- to 7-fold higher affinities than melatonin for the recombinant monkey MT(1) and MT(2) melatonin receptors and monkey suprachiasmatic nucleus membranes. This higher affinity of ramelteon compared with melatonin has also been observed in human melatonin receptors. Furthermore, ramelteon inhibited pituitary adenylate cyclase-activating polypeptide-27-stimulated cAMP production with higher potency than melatonin. In conclusion, this information will help us to understand the pharmacological effects of melatonin receptor agonists in monkeys.
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Affiliation(s)
- Keiji Nishiyama
- Pharmacology Research Laboratory, Pharmaceutical Research Division, Takeda Pharmaceutical Company Ltd, 17-85, Jusohonmachi 2-chome, Yodogawa-ku, Osaka 532-8686, Japan
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36
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Ishii H, Tanaka N, Kobayashi M, Kato M, Sakuma Y. Gene structures, biochemical characterization and distribution of rat melatonin receptors. J Physiol Sci 2009; 59:37-47. [PMID: 19340560 PMCID: PMC10717452 DOI: 10.1007/s12576-008-0003-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2008] [Accepted: 10/10/2008] [Indexed: 12/15/2022]
Abstract
G-protein coupled receptors for the pineal hormone melatonin have been partially cloned from rats. However, insufficient information about their cDNA sequences has hindered studies of their distribution and physiological responses to melatonin using rats as an animal model. We have cloned cDNAs of two rat membrane melatonin receptor subtypes, melatonin receptor 1a (MT1) and melatonin receptor 1b (MT2), using a rapid amplification of cDNA end (RACE) method. The rat MT1 and MT2 cDNAs encode proteins of 353 and 364 amino acids, respectively, and show 78-93% identities with the human and mouse counterparts. Stable expression of either rat MT1 or MT2 in NIH3T3 cells resulted in high affinity 2-[(125)I]-iodomelatonin ((125)I-Mel) binding (K (d) = 73.2 +/- 9.0 and 73.7 +/- 2.9 pM, respectively), and exhibited a similar rank order of inhibition of specific (125)I-Mel binding by five ligands (2-iodomelatonin > melatonin > 6-hydroxymelatonin > luzindole > N-acetyl-5-hydroxytryptamine). RT-PCR analysis showed that MT1 is highly expressed in the hypothalamus, lung, kidney, adrenal gland, stomach, and ovary, while MT2 is highly expressed in the hippocampus, kidney, and ovary. We also performed multi-cell RT-PCR to examine the expression of mRNAs encoding MT1 and MT2 in adult GnRH neurons. MT1 was weakly expressed in male GnRH neurons, and was less expressed in the female neurons. MT2 expression was undetectable in GnRH neurons from either sex. This study delineates the gene structures, fundamental properties, and distribution of both rat melatonin receptor subtypes, and may offer opportunities to assess the physiological significance of melatonin in rats.
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MESH Headings
- Amino Acid Sequence
- Animals
- Base Sequence
- Brain/physiology
- Cloning, Molecular
- Endocrine Glands/physiology
- Gonadotropin-Releasing Hormone/metabolism
- Green Fluorescent Proteins/genetics
- Kidney/physiology
- Lung/physiology
- Melatonin/metabolism
- Mice
- Molecular Sequence Data
- NIH 3T3 Cells
- Nucleic Acid Amplification Techniques
- RNA, Messenger/genetics
- Rats
- Rats, Transgenic
- Rats, Wistar
- Receptor, Melatonin, MT1/genetics
- Receptor, Melatonin, MT1/metabolism
- Receptor, Melatonin, MT2/genetics
- Receptor, Melatonin, MT2/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Stomach/physiology
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Affiliation(s)
- Hirotaka Ishii
- Department of Physiology, Nippon Medical School, Bunkyo-ku, Tokyo, 113-8602, Japan.
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Boutin JA, Marcheteau E, Hennig P, Moulharat N, Berger S, Delagrange P, Bouchet JP, Ferry G. MT3/QR2 melatonin binding site does not use melatonin as a substrate or a co-substrate. J Pineal Res 2008; 45:524-31. [PMID: 18826489 DOI: 10.1111/j.1600-079x.2008.00631.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Quinone reductase 2 (QR2, E.C. 1.10.99.2) is implicated in cell reactive oxygen species production. The catalytic activity of this enzyme is inhibited by 1 microM of melatonin. QR2 was identified as the third melatonin binding site (MT3). It is of major importance to understand the exact roles of melatonin and QR2 in oxidative stress. A fascinating possibility that melatonin could serve as a co-substrate or substrate of QR2 was hypothesized recently. In the current investigation, nuclear magnetic resonance studies of the QR2 catalytic reaction were performed, the results led us to conclude that, whatever the conditions, melatonin is not cleaved off to form N1-acetyl-N2-formyl-5-methoxykynurenine by a catalytically active QR2, very strongly indicating that melatonin is neither a substrate nor a co-substrate of this enzyme. Further studies are needed in order to better understand the relationship between MT3/QR2, melatonin and redox status of the cells, in order to better explain the anti-oxidant activities of melatonin at pharmacological concentrations (>1 microM).
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Affiliation(s)
- Jean A Boutin
- Pharmacologie Moléculaire et Cellulaire, Institut de Recherches Servier, Croissy-sur-Seine, France.
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