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Scherrer KH, Eans SO, Medina JM, Senadheera SN, Khaliq T, Murray TF, McLaughlin JP, Aldrich JV. Tryptophan Substitution in CJ-15,208 ( cyclo[Phe-D-Pro-Phe-Trp]) Introduces δ-Opioid Receptor Antagonism, Preventing Antinociceptive Tolerance and Stress-Induced Reinstatement of Extinguished Cocaine-Conditioned Place Preference. Pharmaceuticals (Basel) 2023; 16:1218. [PMID: 37765026 PMCID: PMC10535824 DOI: 10.3390/ph16091218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 08/11/2023] [Accepted: 08/22/2023] [Indexed: 09/29/2023] Open
Abstract
The macrocyclic tetrapeptide CJ-15,208 (cyclo[Phe-D-Pro-Phe-Trp]) and its D-Trp isomer exhibit kappa opioid receptor (KOR) antagonism which prevents stress-induced reinstatement of extinguished cocaine-conditioned place preference. Here, we evaluated the effects of substitution of Trp and D-Trp on the peptides' opioid activity, antinociceptive tolerance, and the ability to prevent relapse to extinguished drug-CPP. Six analogs were synthesized using a combination of solid-phase peptide synthesis and cyclization in solution. The analogs were evaluated in vitro for opioid receptor affinity in radioligand competition binding assays, efficacy in the [35S]GTPγS assay, metabolic stability in mouse liver microsomes, and for opioid activity and selectivity in vivo in the mouse 55 °C warm-water tail-withdrawal assay. Potential liabilities of locomotor impairment, respiratory depression, acute tolerance, and conditioned place preference (CPP) were also assessed in vivo, and the ameliorating effect of analogs on the reinstatement of extinguished cocaine-place preference was assessed. Substitutions of other D-amino acids for D-Trp did not affect (or in one case increased) KOR affinity, while two of the three substitutions of an L-amino acid for Trp decreased KOR affinity. In contrast, all but one substitution increased mu opioid receptor (MOR) affinity in vitro. The metabolic stabilities of the analogs were similar to those of their respective parent peptides, with analogs containing a D-amino acid being much more rapidly metabolized than those containing an L-amino acid in this position. In vivo, CJ-15,208 analogs demonstrated antinociception, although potencies varied over an 80-fold range and the mediating opioid receptors differed by substitution. KOR antagonism was lost for all but the D-benzothienylalanine analog, and the 2'-naphthylalanine analog instead demonstrated significant delta opioid receptor (DOR) antagonism. Introduction of DOR antagonism coincided with reduced acute opioid antinociceptive tolerance and prevented stress-induced reinstatement of extinguished cocaine-CPP.
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Affiliation(s)
- Kristen H. Scherrer
- Department of Pharmacodynamics, The University of Florida, Gainesville, FL 32610, USA; (K.H.S.); (S.O.E.); (J.M.M.)
| | - Shainnel O. Eans
- Department of Pharmacodynamics, The University of Florida, Gainesville, FL 32610, USA; (K.H.S.); (S.O.E.); (J.M.M.)
| | - Jessica M. Medina
- Department of Pharmacodynamics, The University of Florida, Gainesville, FL 32610, USA; (K.H.S.); (S.O.E.); (J.M.M.)
| | - Sanjeewa N. Senadheera
- Department of Medicinal Chemistry, The University of Kansas, Lawrence, KS 66045, USA; (S.N.S.); (T.K.)
| | - Tanvir Khaliq
- Department of Medicinal Chemistry, The University of Kansas, Lawrence, KS 66045, USA; (S.N.S.); (T.K.)
- Department of Medicinal Chemistry, The University of Florida, Gainesville, FL 32610, USA
| | - Thomas F. Murray
- Department of Pharmacology and Neuroscience, Creighton University School of Medicine, Omaha, NE 68178, USA;
| | - Jay P. McLaughlin
- Department of Pharmacodynamics, The University of Florida, Gainesville, FL 32610, USA; (K.H.S.); (S.O.E.); (J.M.M.)
| | - Jane V. Aldrich
- Department of Medicinal Chemistry, The University of Kansas, Lawrence, KS 66045, USA; (S.N.S.); (T.K.)
- Department of Medicinal Chemistry, The University of Florida, Gainesville, FL 32610, USA
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2
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Gaborit M, Massotte D. Therapeutic potential of opioid receptor heteromers in chronic pain and associated comorbidities. Br J Pharmacol 2023; 180:994-1013. [PMID: 34883528 DOI: 10.1111/bph.15772] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 06/07/2021] [Accepted: 07/21/2021] [Indexed: 11/27/2022] Open
Abstract
Chronic pain affects 20% to 45% of the global population and is often associated with the development of anxio-depressive disorders. Treatment of this debilitating condition remains particularly challenging with opioids prescribed to alleviate moderate to severe pain. However, despite strong antinociceptive properties, numerous adverse effects limit opioid use in the clinic. Moreover, opioid misuse and abuse have become a major health concern worldwide. This prompted efforts to design original strategies that would efficiently and safely relieve pain. Targeting of opioid receptor heteromers is one of these. This review summarizes our current knowledge on the role of heteromers involving opioid receptors in the context of chronic pain and anxio-depressive comorbidities. It also examines how heteromerization in native tissue affects ligand binding, receptor signalling and trafficking properties. Finally, the therapeutic potential of ligands designed to specifically target opioid receptor heteromers is considered. LINKED ARTICLES: This article is part of a themed issue on Advances in Opioid Pharmacology at the Time of the Opioid Epidemic. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v180.7/issuetoc.
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Affiliation(s)
- Marion Gaborit
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Dominique Massotte
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
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3
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Coutens B, Ingram SL. Key differences in regulation of opioid receptors localized to presynaptic terminals compared to somas: Relevance for novel therapeutics. Neuropharmacology 2023; 226:109408. [PMID: 36584882 PMCID: PMC9898207 DOI: 10.1016/j.neuropharm.2022.109408] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 12/05/2022] [Accepted: 12/27/2022] [Indexed: 12/29/2022]
Abstract
Opioid receptors are G protein-coupled receptors (GPCRs) that regulate activity within peripheral, subcortical and cortical circuits involved in pain, reward, and aversion processing. Opioid receptors are expressed in both presynaptic terminals where they inhibit neurotransmitter release and postsynaptic locations where they act to hyperpolarize neurons and reduce activity. Agonist activation of postsynaptic receptors at the plasma membrane signal via ion channels or cytoplasmic second messengers. Agonist binding initiates regulatory processes that include phosphorylation by G protein receptor kinases (GRKs) and recruitment of beta-arrestins that desensitize and internalize the receptors. Opioid receptors also couple to effectors from endosomes activating intracellular enzymes and kinases. In contrast to postsynaptic opioid receptors, receptors localized to presynaptic terminals are resistant to desensitization such that there is no loss of signaling in the continuous presence of opioids over the same time scale. Thus, the balance of opioid signaling in circuits expressing pre- and postsynaptic opioid receptors is shifted toward inhibition of presynaptic neurotransmitter release during continuous opioid exposure. The functional implication of this shift is not often acknowledged in behavioral studies. This review covers what is currently understood about regulation of opioid/nociceptin receptors, with an emphasis on opioid receptor signaling in pain and reward circuits. Importantly, the review covers regulation of presynaptic receptors and the critical gaps in understanding this area, as well as the opportunities to further understand opioid signaling in brain circuits. This article is part of the Special Issue on "Opioid-induced changes in addiction and pain circuits".
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Affiliation(s)
- Basile Coutens
- Department of Anesthesiology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Susan L Ingram
- Department of Anesthesiology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA.
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4
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Asghar J, Latif L, Alexander SPH, Kendall DA. Development of a novel cell-based, In-Cell Western/ERK assay system for the high-throughput screening of agonists acting on the delta-opioid receptor. Front Pharmacol 2022; 13:933356. [PMID: 36225576 PMCID: PMC9549385 DOI: 10.3389/fphar.2022.933356] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 08/08/2022] [Indexed: 11/13/2022] Open
Abstract
Background: Extracellular signal-regulated kinases (ERKs) are important signaling mediators in mammalian cells and, as a result, one of the major areas of research focus. The detection and quantification of ERK phosphorylation as an index of activation is normally conducted using immunoblotting, which does not allow high-throughput drug screening. Plate-based immunocytochemical assays provide a cheaper and relatively high-throughput alternative method for quantifying ERK phosphorylation. Here, we present optimization steps aimed to increase assay sensitivity and reduce variance and cost using the LI-COR In-Cell Western (I-CW) system in a recombinant CHO-K1 cell line, over-expressing the human delta-opioid receptor (hDOPr) as a model.Methods: Cells cultured in 96-well microassay plates were stimulated with three standard/selective DOPr agonists (SNC80, ADL5859, and DADLE) and a novel selective DOPr agonist (PN6047) to elicit a phospho-ERK response as an index of activation. A number of experimental conditions were investigated during the assay development.Key results: Preliminary experiments revealed a clearly visible edge-effect which significantly increased assay variance across the plate and which was reduced by pre-incubation for 30 min at room temperature. ERK phosphorylation was detectable as early as 1 min after agonist addition, with a distinct peak at 3–5 min. Optimization of the cell seeding densities showed that 25,000 cells per well have the lowest basal phospho-ERK response and an optimal agonist ERK1/2 signal. Pre-incubation with apyrase (an ATPase) did not reduce the basal or agonist responses. All agonists produced concentration-dependent increases in phospho-ERK activation, and pertussis toxin was able to attenuate these ERK responses. Naltrindole, which is a selective DOPr antagonist, was able to antagonize the DOPr-mediated ERK activation of the ligands.Conclusion: We have developed an optimization protocol and highlighted a number of considerations when performing this high-throughput fluorescence immunocytochemical (ICC) assay measuring ERK phosphorylation in the human DOPr. The optimized protocol was found to be a more conducive option for the screening of delta agonists. This provides a basis for additional assay development to investigate opioid pharmacology. This protocol should be widely applicable for measuring ERK phosphorylation in any cell line and investigating other protein targets in GPCR drug discovery.
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Affiliation(s)
- Junaid Asghar
- Faculty of Pharmacy, Gomal University, Dera Ismail Khan, Pakistan
- School of Life Sciences, Faculty of Medicine and Health Sciences, Medical School, QMC, University of Nottingham, Nottingham, United Kingdom
- *Correspondence: Junaid Asghar,
| | - Liaque Latif
- School of Life Sciences, Faculty of Medicine and Health Sciences, Medical School, QMC, University of Nottingham, Nottingham, United Kingdom
| | - Stephen P. H. Alexander
- School of Life Sciences, Faculty of Medicine and Health Sciences, Medical School, QMC, University of Nottingham, Nottingham, United Kingdom
| | - David A. Kendall
- School of Life Sciences, Faculty of Medicine and Health Sciences, Medical School, QMC, University of Nottingham, Nottingham, United Kingdom
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Gutridge AM, Chakraborty S, Varga BR, Rhoda ES, French AR, Blaine AT, Royer QH, Cui H, Yuan J, Cassell RJ, Szabó M, Majumdar S, van Rijn RM. Evaluation of Kratom Opioid Derivatives as Potential Treatment Option for Alcohol Use Disorder. Front Pharmacol 2021; 12:764885. [PMID: 34803709 PMCID: PMC8596301 DOI: 10.3389/fphar.2021.764885] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 10/08/2021] [Indexed: 12/13/2022] Open
Abstract
Background and Purpose:Mitragyna speciosa extract and kratom alkaloids decrease alcohol consumption in mice at least in part through actions at the δ-opioid receptor (δOR). However, the most potent opioidergic kratom alkaloid, 7-hydroxymitragynine, exhibits rewarding properties and hyperlocomotion presumably due to preferred affinity for the mu opioid receptor (µOR). We hypothesized that opioidergic kratom alkaloids like paynantheine and speciogynine with reduced µOR potency could provide a starting point for developing opioids with an improved therapeutic window to treat alcohol use disorder. Experimental Approach: We characterized paynantheine, speciociliatine, and four novel kratom-derived analogs for their ability to bind and activate δOR, µOR, and κOR. Select opioids were assessed in behavioral assays in male C57BL/6N WT and δOR knockout mice. Key Results: Paynantheine (10 mg∙kg−1, i.p.) produced aversion in a limited conditioned place preference (CPP) paradigm but did not produce CPP with additional conditioning sessions. Paynantheine did not produce robust antinociception but did block morphine-induced antinociception and hyperlocomotion. Yet, at 10 and 30 mg∙kg−1 doses (i.p.), paynantheine did not counteract morphine CPP. 7-hydroxypaynantheine and 7-hydroxyspeciogynine displayed potency at δOR but limited µOR potency relative to 7-hydroxymitragynine in vitro, and dose-dependently decreased voluntary alcohol consumption in WT but not δOR in KO mice. 7-hydroxyspeciogynine has a maximally tolerated dose of at least 10 mg∙kg−1 (s.c.) at which it did not produce significant CPP neither alter general locomotion nor induce noticeable seizures. Conclusion and Implications: Derivatizing kratom alkaloids with the goal of enhancing δOR potency and reducing off-target effects could provide a pathway to develop novel lead compounds to treat alcohol use disorder with an improved therapeutic window.
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Affiliation(s)
- Anna M Gutridge
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
| | - Soumen Chakraborty
- Center for Clinical Pharmacology, University of Heath Sciences and Pharmacy at St. Louis and Washington University School of Medicine, St. Louis, MO, United States
| | - Balazs R Varga
- Center for Clinical Pharmacology, University of Heath Sciences and Pharmacy at St. Louis and Washington University School of Medicine, St. Louis, MO, United States
| | - Elizabeth S Rhoda
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
| | - Alexander R French
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States.,Purdue Institute for Integrative Neuroscience, West Lafayette, IN, United States
| | - Arryn T Blaine
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
| | - Quinten H Royer
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
| | - Haoyue Cui
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
| | - Jinling Yuan
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
| | - Robert J Cassell
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States.,Purdue Institute for Drug Discovery, West Lafayette, IN, United States
| | | | - Susruta Majumdar
- Center for Clinical Pharmacology, University of Heath Sciences and Pharmacy at St. Louis and Washington University School of Medicine, St. Louis, MO, United States
| | - Richard M van Rijn
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States.,Purdue Institute for Integrative Neuroscience, West Lafayette, IN, United States.,Purdue Institute for Drug Discovery, West Lafayette, IN, United States
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6
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Moye LS, Siegersma K, Dripps I, Witkowski W, Mangutov E, Wang D, Scherrer G, Pradhan AA. Delta opioid receptor regulation of calcitonin gene-related peptide dynamics in the trigeminal complex. Pain 2021; 162:2297-2308. [PMID: 33605657 PMCID: PMC8730473 DOI: 10.1097/j.pain.0000000000002235] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 02/08/2021] [Indexed: 12/14/2022]
Abstract
ABSTRACT Migraine is highly prevalent and is the sixth leading cause worldwide for years lost to disability. Therapeutic options specifically targeting migraine are limited, and delta opioid receptor (DOP) agonists were recently identified as a promising pharmacotherapy. The mechanisms by which DOPs regulate migraine are currently unclear. Calcitonin gene-related peptide (CGRP) has been identified as an endogenous migraine trigger and plays a critical role in migraine initiation and susceptibility. The aim of this study was to determine the behavioral effects of DOP agonists on the development of chronic migraine-associated pain and to investigate DOP coexpression with CGRP and CGRP receptor (CGRPR) in the trigeminal system. Chronic migraine-associated pain was induced in mice through repeated intermittent injection of the known human migraine trigger, nitroglycerin. Chronic nitroglycerin resulted in severe chronic cephalic allodynia which was prevented with cotreatment of the DOP-selective agonist, SNC80. In addition, a corresponding increase in CGRP expression in the trigeminal ganglia and trigeminal nucleus caudalis was observed after chronic nitroglycerin, an augmentation that was blocked by SNC80. Moreover, DOP was also upregulated in these head pain-processing regions following the chronic migraine model. Immunohistochemical analysis of the trigeminal ganglia revealed coexpression of DOP with CGRP as well as with a primary component of the CGRPR, RAMP1. In the trigeminal nucleus caudalis, DOP was not coexpressed with CGRP but was highly coexpressed with RAMP1 and calcitonin receptor-like receptor. These results suggest that DOP agonists inhibit migraine-associated pain by attenuating CGRP release and blocking pronociceptive signaling of the CGRPR.
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Affiliation(s)
- Laura S Moye
- Department of Psychiatry, University of Illinois at Chicago
| | | | - Isaac Dripps
- Department of Psychiatry, University of Illinois at Chicago
| | | | | | - Dong Wang
- Department of Anesthesiology, Perioperative and Pain Medicine, Department of Neurosurgery, Department of Molecular and Cellular Physiology, Stanford Neurosciences Institute, Stanford University, Palo Alto, CA 94304, USA
| | - Grégory Scherrer
- Department of Cell Biology and Physiology, UNC Neuroscience Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- New York Stem Cell Foundation – Robertson Investigator
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7
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Creed SM, Gutridge AM, Argade MD, Hennessy MR, Friesen JB, Pauli GF, van Rijn RM, Riley AP. Isolation and Pharmacological Characterization of Six Opioidergic Picralima nitida Alkaloids. JOURNAL OF NATURAL PRODUCTS 2021; 84:71-80. [PMID: 33326237 PMCID: PMC7932029 DOI: 10.1021/acs.jnatprod.0c01036] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The seeds of the akuamma tree (Picralima nitida) have been used as a traditional treatment for pain and fever. Previous studies have attributed these effects to a series of indole alkaloids found within the seed extracts; however, these pharmacological studies were significantly limited in scope. Herein, an isolation protocol employing pH-zone-refining countercurrent chromatography was developed to provide six of the akuamma alkaloids in high purity and quantities sufficient for more extensive biological evaluation. Five of these alkaloids, akuammine (1), pseudo-akuammigine (3), akuammicine (4), akuammiline (5), and picraline (6), were evaluated against a panel of >40 central nervous system receptors to identify that their primary targets are the opioid receptors. Detailed in vitro investigations revealed 4 to be a potent kappa opioid receptor agonist, and three alkaloids (1-3) were shown to have micromolar activity at the mu opioid receptor. The mu opioid receptor agonists were further evaluated for analgesic properties but demonstrated limited efficacy in assays of thermal nociception. These findings contradict previous reports of the antinociceptive properties of the P. nitida alkaloids and the traditional use of akuamma seeds as analgesics. Nevertheless, their opioid-preferring activity does suggest the akuamma alkaloids provide distinct scaffolds from which novel opioids with unique pharmacologic properties and therapeutic utility can be developed.
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Affiliation(s)
- Simone M Creed
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612, United States
| | - Anna M Gutridge
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
| | - Malaika D Argade
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612, United States
| | - Madeline R Hennessy
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612, United States
| | - J Brent Friesen
- Department of Pharmaceutical Sciences and Pharmacognosy Institute, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612, United States
| | - Guido F Pauli
- Department of Pharmaceutical Sciences and Pharmacognosy Institute, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612, United States
| | - Richard M van Rijn
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue Institute for Drug Discovery, Purdue Institute for Integrative Neuroscience, Purdue Interdisciplinary Life Sciences Graduate Program, Purdue University, West Lafayette, Indiana 47907, United States
| | - Andrew P Riley
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612, United States
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8
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Montagud-Romero S, Cantacorps L, Fernández-Gómez FJ, Núñez C, Miñarro J, Rodríguez-Arias M, Milanés MV, Valverde O. Unraveling the molecular mechanisms involved in alcohol intake and withdrawal in adolescent mice exposed to alcohol during early life stages. Prog Neuropsychopharmacol Biol Psychiatry 2021; 104:110025. [PMID: 32599136 DOI: 10.1016/j.pnpbp.2020.110025] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Revised: 06/19/2020] [Accepted: 06/21/2020] [Indexed: 01/15/2023]
Abstract
Alcohol interferes with foetal development and prenatal alcohol exposure can lead to adverse effects known as foetal alcohol spectrum disorders. We aimed to assess the underlying neurobiological mechanisms involved in alcohol intake and withdrawal in adolescent mice exposed to alcohol during early life stages, in discrete brain areas. Pregnant C57BL/6 female mice were exposed to binge alcohol drinking from gestation to weaning. Subsequently, alcohol seeking and taking behaviour were evaluated in male adolescent offspring, as assessed in the two-bottle choice and oral self-administration paradigms. Brain area samples were analysed to quantify AMPAR subunits GluR1/2 and pCREB/CREB expression following alcohol self-administration. We measured the expression of mu and kappa opioid receptors both during acute alcohol withdrawal (assessing anxiety alterations by the EPM test) and following reinstatement in the two-bottle choice paradigm. In addition, alcohol metabolism was analysed by measuring blood alcohol concentrations under an acute dose of 3 g/kg alcohol. Our findings demonstrate that developmental alcohol exposure enhances alcohol intake during adolescence, which is associated with a decrease in the pCREB/CREB ratio in the hippocampus, prefrontal cortex and striatum, while the GluR1/GluR2 ratio showed a decrease in the hippocampus. Moreover, PLAE mice showed behavioural alterations, such as increased anxiety-like responses during acute alcohol withdrawal, and higher BAC levels. No significant changes were identified for mu and kappa opioid receptors mRNA expression. The current study highlights that early alcohol exposed mice increased alcohol consumption during late adolescence. Furthermore, a diminished CREB signalling and glutamatergic neuroplasticity are proposed as underpinning neurobiological mechanisms involved in the sensitivity to alcohol reinforcing properties.
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Affiliation(s)
- Sandra Montagud-Romero
- Neurobiology of Behaviour Research Group (GReNeC-NeuroBio), Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | - Lídia Cantacorps
- Neurobiology of Behaviour Research Group (GReNeC-NeuroBio), Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain
| | - Francisco José Fernández-Gómez
- Murcia Research Institute of Health Sciences (IMIB), Department of Pharmacology, Faculty of Medicine, University of Murcia, Murcia, Spain
| | - Cristina Núñez
- Murcia Research Institute of Health Sciences (IMIB), Department of Pharmacology, Faculty of Medicine, University of Murcia, Murcia, Spain
| | - José Miñarro
- Department of Psychobiology, Facultad de Psicología, Universitat de Valencia, Avda. Blasco Ibáñez, 21, 46010 Valencia, Spain; Red Temática de Investigación Cooperativa en Salud (RETICS-Trastornos Adictivos), Instituto de Salud Carlos III, MICINN and FEDER, Madrid, Spain
| | - Marta Rodríguez-Arias
- Department of Psychobiology, Facultad de Psicología, Universitat de Valencia, Avda. Blasco Ibáñez, 21, 46010 Valencia, Spain; Red Temática de Investigación Cooperativa en Salud (RETICS-Trastornos Adictivos), Instituto de Salud Carlos III, MICINN and FEDER, Madrid, Spain
| | - María Victoria Milanés
- Murcia Research Institute of Health Sciences (IMIB), Department of Pharmacology, Faculty of Medicine, University of Murcia, Murcia, Spain
| | - Olga Valverde
- Neurobiology of Behaviour Research Group (GReNeC-NeuroBio), Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona, Spain; Red Temática de Investigación Cooperativa en Salud (RETICS-Trastornos Adictivos), Instituto de Salud Carlos III, MICINN and FEDER, Madrid, Spain; IMIM-Hospital del Mar Medical Research Institute, Neurosciences Programme, Barcelona, Spain.
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9
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Ding Z, Knipp GT, van Rijn RM, Chester JA, Watts VJ. The CUL3/neddylation inhibitor MLN4924 reduces ethanol-induced locomotor sensitization and inflammatory pain allodynia in mice. Behav Brain Res 2020; 399:113051. [PMID: 33279641 DOI: 10.1016/j.bbr.2020.113051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 10/01/2020] [Accepted: 11/25/2020] [Indexed: 11/16/2022]
Abstract
Heterologous sensitization of adenylyl cyclase (AC) is defined by an enhanced cAMP response following persistent activation of Gαi/o-coupled receptors. This phenomenon was first observed in cellular models, and later reported in animal models of inflammatory pain or following chronic exposure to drugs of abuse including opioids and cocaine. Recently, we used genome-wide siRNA screening to identify Cullin3 signaling as a mediator of AC sensitization in cellular models. We also showed that pharmacological inhibition of Cullin3 with the neddylation inhibitor, MLN4924, abolished heterologous sensitization of several AC isoforms, including AC1, AC2, AC5, and AC6. Because ACs, especially AC1, have been implicated in alcohol-induced locomotor sensitization and inflammatory pain, we assessed the potential activity of MLN4924 in both murine models. We found that MLN4924 (30 mg/kg, i.p.) accumulated in the brain and reduced both locomotor sensitization induced by repeated alcohol administration and allodynia in an inflammatory pain model. Based on our previous findings that MLN4924 potently blocks AC sensitization in cellular models, we propose that the activity of MLN4924 in both animal models potentially occurs through blocking AC sensitization. Our findings provide the basis for understanding the molecular mechanism and yield a new pathway for drug development for pathological disorders associated with AC sensitization.
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Affiliation(s)
- Zhong Ding
- Dept of Medicinal Chemistry & Molecular Pharmacology, Purdue University, West Lafayette, IN, 47907, USA
| | - Gregory T Knipp
- Dept of Industrial and Physical Pharmacy, Purdue University, West Lafayette, IN, 47907, USA; Purdue Institute for Drug Discovery, Purdue University, West Lafayette, IN, 47907, USA
| | - Richard M van Rijn
- Dept of Medicinal Chemistry & Molecular Pharmacology, Purdue University, West Lafayette, IN, 47907, USA; Purdue Institute for Drug Discovery, Purdue University, West Lafayette, IN, 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Julia A Chester
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA; Dept of Psychological Sciences, Purdue University, West Lafayette, IN, 47907, USA
| | - Val J Watts
- Dept of Medicinal Chemistry & Molecular Pharmacology, Purdue University, West Lafayette, IN, 47907, USA; Purdue Institute for Drug Discovery, Purdue University, West Lafayette, IN, 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA.
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10
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Vena AA, Zandy SL, Cofresí RU, Gonzales RA. Behavioral, neurobiological, and neurochemical mechanisms of ethanol self-administration: A translational review. Pharmacol Ther 2020; 212:107573. [PMID: 32437827 PMCID: PMC7580704 DOI: 10.1016/j.pharmthera.2020.107573] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/29/2020] [Indexed: 12/16/2022]
Abstract
Alcohol use disorder has multiple characteristics including excessive ethanol consumption, impaired control over drinking behaviors, craving and withdrawal symptoms, compulsive seeking behaviors, and is considered a chronic condition. Relapse is common. Determining the neurobiological targets of ethanol and the adaptations induced by chronic ethanol exposure is critical to understanding the clinical manifestation of alcohol use disorders, the mechanisms underlying the various features of the disorder, and for informing medication development. In the present review, we discuss ethanol's interactions with a variety of neurotransmitter systems, summarizing findings from preclinical and translational studies to highlight recent progress in the field. We then describe animal models of ethanol self-administration, emphasizing the value, limitations, and validity of commonly used models. Lastly, we summarize the behavioral changes induced by chronic ethanol self-administration, with an emphasis on cue-elicited behavior, the role of ethanol-related memories, and the emergence of habitual ethanol seeking behavior.
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Affiliation(s)
- Ashley A Vena
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, United States of America
| | | | - Roberto U Cofresí
- Psychological Sciences, University of Missouri, United States of America
| | - Rueben A Gonzales
- Division of Pharmacology and Toxicology, College of Pharmacy and Institute for Neuroscience, The University of Texas at Austin, United States of America.
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11
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Robins MT, Heinricher MM, Ryabinin AE. From Pleasure to Pain, and Back Again: The Intricate Relationship Between Alcohol and Nociception. Alcohol Alcohol 2020; 54:625-638. [PMID: 31509854 DOI: 10.1093/alcalc/agz067] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 07/09/2019] [Accepted: 07/10/2019] [Indexed: 02/07/2023] Open
Abstract
AIMS A close and bidirectional relationship between alcohol consumption and pain has been previously reported and discussed in influential reviews. The goal of the present narrative review is to provide an update on the developments in this field in order to guide future research objectives. METHODS We evaluated both epidemiological and neurobiological literature interrogating the relationship between alcohol use and pain for the presence of significant effects. We outlined studies on interactions between alcohol use and pain using both self-reports and objective experimental measures and discussed potential underlying mechanisms of these interactions. RESULTS Epidemiological, preclinical and clinical literature point to three major interactions between alcohol use and pain: (a) alcohol use leading to hyperalgesia, (b) alcohol use moderating pain and hyperalgesia and (c) chronic pain as a risk factor predisposing to alcohol relapse. Neurobiological studies using animal models to assess these interactions have transitioned from mostly involuntary modes of experimenter-controlled alcohol administration to self-administration procedures, and increasingly indicate that neuronal circuits implicated in both withdrawal and anticipation stages of alcohol use disorder also have a role in chronic pain. Mechanistically, alterations in GABA, glutamate, the corticotropin-releasing factor system, endogenous opioids and protein kinase C appear to play crucial roles in this maladaptive overlap. CONCLUSIONS Many of the principles explaining the interactions between alcohol and pain remain on a strong foundation, but continuing progress in modeling these interactions and underlying systems will provide a clearer basis for understanding, and ultimately treating, the damaging aspects of this interaction.
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Affiliation(s)
- Meridith T Robins
- Department of Behavioral Neuroscience, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA
| | - Mary M Heinricher
- Department of Behavioral Neuroscience, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA.,Department of Neurological Surgery, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA
| | - Andrey E Ryabinin
- Department of Behavioral Neuroscience, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA
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12
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Gutridge AM, Robins MT, Cassell RJ, Uprety R, Mores KL, Ko MJ, Pasternak GW, Majumdar S, van Rijn RM. G protein-biased kratom-alkaloids and synthetic carfentanil-amide opioids as potential treatments for alcohol use disorder. Br J Pharmacol 2020; 177:1497-1513. [PMID: 31705528 PMCID: PMC7060366 DOI: 10.1111/bph.14913] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 10/12/2019] [Accepted: 10/15/2019] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND AND PURPOSE Mitragyna speciosa, more commonly known as kratom, is a plant that contains opioidergic alkaloids but is unregulated in most countries. Kratom is used in the self-medication of chronic pain and to reduce illicit and prescription opioid dependence. Kratom may be less dangerous than typical opioids because of the stronger preference of kratom alkaloids to induce receptor interaction with G proteins over β-arrestin proteins. We hypothesized that kratom (alkaloids) can also reduce alcohol intake. EXPERIMENTAL APPROACH We pharmacologically characterized kratom extracts, kratom alkaloids (mitragynine, 7-hydroxymitragynine, paynantheine, and speciogynine) and synthetic carfentanil-amide opioids for their ability to interact with G proteins and β-arrestin at μ, δ, and κ opioid receptors in vitro. We used C57BL/6 mice to assess to which degree these opioids could reduce alcohol intake and whether they had rewarding properties. KEY RESULTS Kratom alkaloids were strongly G protein-biased at all three opioid receptors and reduced alcohol intake, but kratom and 7-hydroxymitragynine were rewarding. Several results indicated a key role for δ opioid receptors, including that the synthetic carfentanil-amide opioid MP102-a G protein-biased agonist with modest selectivity for δ opioid receptors-reduced alcohol intake, whereas the G protein-biased μ opioid agonist TRV130 did not. CONCLUSION AND IMPLICATIONS Our results suggest that kratom extracts can decrease alcohol intake but still carry significant risk upon prolonged use. Development of more δ opioid-selective synthetic opioids may provide a safer option than kratom to treat alcohol use disorder with fewer side effects.
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Affiliation(s)
- Anna M. Gutridge
- Department of Medicinal Chemistry and Molecular Pharmacology, College of PharmacyPurdue UniversityWest LafayetteIndiana
| | - Meridith T. Robins
- Department of Medicinal Chemistry and Molecular Pharmacology, College of PharmacyPurdue UniversityWest LafayetteIndiana
| | - Robert J. Cassell
- Department of Medicinal Chemistry and Molecular Pharmacology, College of PharmacyPurdue UniversityWest LafayetteIndiana
| | - Rajendra Uprety
- Department of Neurology and Molecular PharmacologyMemorial Sloan Kettering Cancer CenterNew YorkNew York
| | - Kendall L. Mores
- Department of Medicinal Chemistry and Molecular Pharmacology, College of PharmacyPurdue UniversityWest LafayetteIndiana
| | - Mee Jung Ko
- Department of Medicinal Chemistry and Molecular Pharmacology, College of PharmacyPurdue UniversityWest LafayetteIndiana
- Purdue Interdisciplinary Life Sciences Graduate ProgramPurdue UniversityWest LafayetteIndiana
| | - Gavril W. Pasternak
- Department of Neurology and Molecular PharmacologyMemorial Sloan Kettering Cancer CenterNew YorkNew York
| | - Susruta Majumdar
- Department of Neurology and Molecular PharmacologyMemorial Sloan Kettering Cancer CenterNew YorkNew York
- Center for Clinical PharmacologySt. Louis College of Pharmacy and Washington University School of MedicineSt. LouisMissouri
| | - Richard M. van Rijn
- Department of Medicinal Chemistry and Molecular Pharmacology, College of PharmacyPurdue UniversityWest LafayetteIndiana
- Purdue Institute for Drug DiscoveryPurdue UniversityWest LafayetteIndiana
- Purdue Institute for Integrative NeurosciencePurdue UniversityWest LafayetteIndiana
- Purdue Interdisciplinary Life Sciences Graduate ProgramPurdue UniversityWest LafayetteIndiana
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13
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Neasta J, Darcq E, Jeanblanc J, Carnicella S, Ben Hamida S. GPCR and Alcohol-Related Behaviors in Genetically Modified Mice. Neurotherapeutics 2020; 17:17-42. [PMID: 31919661 PMCID: PMC7007453 DOI: 10.1007/s13311-019-00828-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
G protein-coupled receptors (GPCRs) constitute the largest class of cell surface signaling receptors and regulate major neurobiological processes. Accordingly, GPCRs represent primary targets for the treatment of brain disorders. Several human genetic polymorphisms affecting GPCRs have been associated to different components of alcohol use disorder (AUD). Moreover, GPCRs have been reported to contribute to several features of alcohol-related behaviors in animal models. Besides traditional pharmacological tools, genetic-based approaches mostly aimed at deleting GPCR genes provided substantial information on how key GPCRs drive alcohol-related behaviors. In this review, we summarize the alcohol phenotypes that ensue from genetic manipulation, in particular gene deletion, of key GPCRs in rodents. We focused on GPCRs that belong to fundamental neuronal systems that have been shown as potential targets for the development of AUD treatment. Data are reviewed with particular emphasis on alcohol reward, seeking, and consumption which are behaviors that capture essential aspects of AUD. Literature survey indicates that in most cases, there is still a gap in defining the intracellular transducers and the functional crosstalk of GPCRs as well as the neuronal populations in which their signaling regulates alcohol actions. Further, the implication of only a few orphan GPCRs has been so far investigated in animal models. Combining advanced pharmacological technologies with more specific genetically modified animals and behavioral preclinical models is likely necessary to deepen our understanding in how GPCR signaling contributes to AUD and for drug discovery.
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Affiliation(s)
- Jérémie Neasta
- Laboratoire de Pharmacologie, Faculté de Pharmacie, University of Montpellier, 34093, Montpellier, France
| | - Emmanuel Darcq
- Douglas Hospital Research Center, Department of Psychiatry, McGill University, 6875 Boulevard LaSalle, Montreal, Quebec, H4H 1R3, Canada
| | - Jérôme Jeanblanc
- Research Group on Alcohol and Pharmacodependences-INSERM U1247, University of Picardie Jules Verne, 80025, Amiens, France
| | - Sebastien Carnicella
- INSERM U1216, Grenoble Institut des Neurosciences (GIN), University of Grenoble Alpes, 38000, Grenoble, France
| | - Sami Ben Hamida
- Douglas Hospital Research Center, Department of Psychiatry, McGill University, 6875 Boulevard LaSalle, Montreal, Quebec, H4H 1R3, Canada.
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14
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Moye LS, Tipton AF, Dripps I, Sheets Z, Crombie A, Violin JD, Pradhan AA. Delta opioid receptor agonists are effective for multiple types of headache disorders. Neuropharmacology 2019; 148:77-86. [PMID: 30553828 PMCID: PMC6467218 DOI: 10.1016/j.neuropharm.2018.12.017] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 11/19/2018] [Accepted: 12/12/2018] [Indexed: 12/20/2022]
Abstract
Headaches are highly disabling and are among the most common neurological disorders worldwide. Despite the high prevalence of headache, therapeutic options are limited. We recently identified the delta opioid receptor (DOR) as an emerging therapeutic target for migraine. In this study, we examined the effectiveness of a hallmark DOR agonist, SNC80, in disease models reflecting diverse headache disorders including: chronic migraine, post-traumatic headache (PTH), medication overuse headache by triptans (MOH), and opioid-induced hyperalgesia (OIH). To model chronic migraine C57BL/6J mice received chronic intermittent treatment with the known human migraine trigger, nitroglycerin. PTH was modeled by combining the closed head weight drop model with the nitroglycerin model of chronic migraine. For MOH and OIH, mice were chronically treated with sumatriptan or morphine, respectively. The development of periorbital and peripheral allodynia was observed in all four models; and SNC80 significantly inhibited allodynia in all cases. In addition, we also determined if chronic daily treatment with SNC80 would induce MOH/OIH, and we observed limited hyperalgesia relative to sumatriptan or morphine. Together, our results indicate that DOR agonists could be effective in multiple headache disorders, despite their distinct etiology, thus presenting a novel therapeutic target for headache.
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Affiliation(s)
- Laura S Moye
- Department of Psychiatry, University of Illinois at Chicago, USA
| | - Alycia F Tipton
- Department of Psychiatry, University of Illinois at Chicago, USA
| | - Isaac Dripps
- Department of Psychiatry, University of Illinois at Chicago, USA
| | - Zoie Sheets
- Department of Psychiatry, University of Illinois at Chicago, USA
| | | | | | - Amynah A Pradhan
- Department of Psychiatry, University of Illinois at Chicago, USA.
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15
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Ko MJ, Ganzen LC, Coskun E, Mukadam AA, Leung YF, van Rijn RM. A critical evaluation of TRPA1-mediated locomotor behavior in zebrafish as a screening tool for novel anti-nociceptive drug discovery. Sci Rep 2019; 9:2430. [PMID: 30787340 PMCID: PMC6382835 DOI: 10.1038/s41598-019-38852-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 01/11/2019] [Indexed: 12/12/2022] Open
Abstract
Current medications inadequately treat the symptoms of chronic pain experienced by over 50 million people in the United States, and may come with substantial adverse effects signifying the need to find novel treatments. One novel therapeutic target is the Transient Receptor Potential A1 channel (TRPA1), an ion channel that mediates nociception through calcium influx of sensory neurons. Drug discovery still relies heavily on animal models, including zebrafish, a species in which TRPA1 activation produces hyperlocomotion. Here, we investigated if this hyperlocomotion follows zebrafish TRPA1 pharmacology and evaluated the strengths and limitations of using TRPA1-mediated hyperlocomotion as potential preclinical screening tool for drug discovery. To support face validity of the model, we pharmacologically characterized mouse and zebrafish TRPA1 in transfected HEK293 cells using calcium assays as well as in vivo. TRPA1 agonists and antagonists respectively activated or blocked TRPA1 activity in HEK293 cells, mice, and zebrafish in a dose-dependent manner. However, our results revealed complexities including partial agonist activity of TRPA1 antagonists, bidirectional locomotor activity, receptor desensitization, and off-target effects. We propose that TRPA1-mediated hyperlocomotion in zebrafish larvae has the potential to be used as in vivo screening tool for novel anti-nociceptive drugs but requires careful evaluation of the TRPA1 pharmacology.
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Affiliation(s)
- Mee Jung Ko
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, West Lafayette, USA.,Purdue Institute for Integrative Neuroscience, West Lafayette, USA.,Purdue Interdisciplinary Life Sciences Graduate Program, West Lafayette, USA
| | - Logan C Ganzen
- Department of Biological Sciences, College of Science, West Lafayette, USA.,Purdue Institute for Integrative Neuroscience, West Lafayette, USA.,Purdue Interdisciplinary Life Sciences Graduate Program, West Lafayette, USA
| | - Emre Coskun
- Department of Biological Sciences, College of Science, West Lafayette, USA
| | - Arbaaz A Mukadam
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, West Lafayette, USA
| | - Yuk Fai Leung
- Department of Biological Sciences, College of Science, West Lafayette, USA.,Purdue Institute for Integrative Neuroscience, West Lafayette, USA.,Purdue Interdisciplinary Life Sciences Graduate Program, West Lafayette, USA.,Purdue Institute for Drug Discovery, West Lafayette, USA.,Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, West Lafayette, IN, 47907, USA
| | - Richard M van Rijn
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, West Lafayette, USA. .,Purdue Institute for Integrative Neuroscience, West Lafayette, USA. .,Purdue Interdisciplinary Life Sciences Graduate Program, West Lafayette, USA. .,Purdue Institute for Drug Discovery, West Lafayette, USA.
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16
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Geng J, Yuan Y, Jiao X, Wang R, Liu N, Chen H, Griffin N, Shan F. Novel modulation on myeloid-derived suppressor cells (MDSCs) by methionine encephalin (MENK). Int Immunopharmacol 2019; 68:193-203. [PMID: 30654309 DOI: 10.1016/j.intimp.2019.01.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 01/08/2019] [Accepted: 01/08/2019] [Indexed: 12/21/2022]
Abstract
The purpose of this study was to identify the modulatory effect of MENK on MDSCs and to investigate the relationship between this modulation and the expression of opioid receptors. Our results showed that MENK could inhibit the proliferation of MDSCs from both marine bone marrow and spleen. MENK also could promote the expression of opioid receptors MOR and DOR. MENK suppressed the PMN-MDSCs generated from splenocyte while up-regulated M-MDSCs. The stimulation of MENK increased the production of IL-4 secreted by MDSCs from slpenocytes. Our currently data indicated that MENK could suppress the accumulation of MDSCs in tumor-bearing mice via binding to and up-regulating expressions of subunits of opioid receptors. Therefore, it is concluded that MENK, through triggering opioid receptors could exert inhibiting modulation on MDSCs.
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Affiliation(s)
- Jin Geng
- Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang 110122, China; Department of Ophthalmology, No. 1 Teaching Hospital, China Medical University, Shenyang 110001, China
| | - Ye Yuan
- Department of Neurosurgery, Shengjing Hospital, China Medical University, Shenyang 110016, China
| | - Xue Jiao
- Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang 110122, China
| | - Ruizhe Wang
- Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang 110122, China; Department of Gynecology, No. 1 Teaching Hospital, China Medical University, Shenyang 110001, China
| | - Ning Liu
- Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang 110122, China; Department of Gynecology Oncology, Shengjing Hospital, China Medical University, Shenyang 110016, China
| | - Hao Chen
- Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang 110122, China
| | - Noreen Griffin
- Immune Therapeutics, Inc., 37 North Orange Avenue, Suite 607, Orlando, FL 32801, USA
| | - Fengping Shan
- Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang 110122, China.
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17
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Gendron L, Nagi K, Zeghal M, Giguère PM, Pineyro G. Molecular aspects of delta opioid receptors. OPIOID HORMONES 2019; 111:49-90. [DOI: 10.1016/bs.vh.2019.06.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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18
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Jiao X, Wang X, Wang R, Geng J, Liu N, Chen H, Griffin N, Shan F. Rules to activate CD8 +T cells through regulating subunits of opioid receptors by methionine enkephalin (MENK). Int Immunopharmacol 2018; 65:76-83. [PMID: 30290369 DOI: 10.1016/j.intimp.2018.09.040] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 09/25/2018] [Accepted: 09/25/2018] [Indexed: 12/28/2022]
Abstract
The goal of this work was to investigate how MENK could regulate the functions of CD8+T cells and to explore the relationship between this regulation and opioid receptor expression. Our results showed that the opioid receptors presented on the cell menbrane of CD8+T cells were MOR and DOR. MENK promoted the expression of opioid receptors as well as the elevation of the surface molecules such as CD28, PD-1, CTLA-4 and FasL and intracellular granzyme B. Selectively blocking the MOR by CTAP or DOR by NTI could result in inhibition of the corresponding CD8+T cells proliferation and the expressions of surface molecules. In addition, non-selectively blocking both MOR and DOR by NTX could further impair the functions and proliferation of CD8+T cells. Our currently data indicated that MENK could play a vital role in immune functions via precise regulation to subunits of opioid receptors.
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Affiliation(s)
- Xue Jiao
- Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang 110122, China; Center for Translational Medicine, No. 4 Teaching Hospital, China Medical University, Shenyang 110032, China
| | - Xiaonan Wang
- Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang 110122, China
| | - Ruizhe Wang
- Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang 110122, China; Department of Gynecology, No. 1 Teaching Hospital, China Medical University, Shenyang 110001, China
| | - Jin Geng
- Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang 110122, China; Department of Ophthalmology, No. 1 Teaching Hospital, China Medical University, Shenyang 110001, China
| | - Ning Liu
- Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang 110122, China; Department of Gynecology Oncology, Shengjing Hospital, China Medical University, Shenyang 110016, China
| | - Hao Chen
- Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang 110122, China
| | - Noreen Griffin
- Immune Therapeutics, Inc., 37 North Orange Avenue, Suite 607, Orlando, FL 32801, USA
| | - Fengping Shan
- Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang 110122, China.
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19
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Derouiche L, Massotte D. G protein-coupled receptor heteromers are key players in substance use disorder. Neurosci Biobehav Rev 2018; 106:73-90. [PMID: 30278192 DOI: 10.1016/j.neubiorev.2018.09.026] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2018] [Revised: 09/25/2018] [Accepted: 09/26/2018] [Indexed: 12/19/2022]
Abstract
G protein-coupled receptors (GPCR) represent the largest family of membrane proteins in the human genome. Physical association between two different GPCRs is linked to functional interactions which generates a novel entity, called heteromer, with specific ligand binding and signaling properties. Heteromerization is increasingly recognized to take place in the mesocorticolimbic pathway and to contribute to various aspects related to substance use disorder. This review focuses on heteromers identified in brain areas relevant to drug addiction. We report changes at the molecular and cellular levels that establish specific functional impact and highlight behavioral outcome in preclinical models. Finally, we briefly discuss selective targeting of native heteromers as an innovative therapeutic option.
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Affiliation(s)
- Lyes Derouiche
- Institut des Neurosciences Cellulaires et Integratives, UPR 3212, 5 rue Blaise Pascal, F-67000 Strasbourg, France
| | - Dominique Massotte
- Institut des Neurosciences Cellulaires et Integratives, UPR 3212, 5 rue Blaise Pascal, F-67000 Strasbourg, France.
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20
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Robins MT, Chiang T, Mores KL, Alongkronrusmee D, van Rijn RM. Critical Role for G i/o-Protein Activity in the Dorsal Striatum in the Reduction of Voluntary Alcohol Intake in C57Bl/6 Mice. Front Psychiatry 2018; 9:112. [PMID: 29686629 PMCID: PMC5900748 DOI: 10.3389/fpsyt.2018.00112] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 03/19/2018] [Indexed: 12/21/2022] Open
Abstract
The transition from non-dependent alcohol use to alcohol dependence involves increased activity of the dorsal striatum. Interestingly, the dorsal striatum expresses a large number of inhibitory G-protein-coupled receptors (GPCRs), which when activated may inhibit alcohol-induced increased activity and can decrease alcohol consumption. Here, we explore the hypothesis that dorsal striatal Gi/o-protein activation is sufficient to reduce voluntary alcohol intake. Using a voluntary, limited-access, two-bottle choice, drink-in-the-dark model of alcohol (10%) consumption, we validated the importance of Gi/o signaling in this region by locally expressing neuron-specific, adeno-associated-virus encoded Gi/o-coupled muscarinic M4 designer receptors exclusively activated by designer drugs (DREADD) in the dorsal striatum and observed a decrease in alcohol intake upon DREADD activation. We validated our findings by activating Gi/o-coupled delta-opioid receptors (DORs), which are natively expressed in the dorsal striatum, using either a G-protein biased agonist or a β-arrestin-biased agonist. Local infusion of TAN-67, an in vitro-determined Gi/o-protein biased DOR agonist, decreased voluntary alcohol intake in wild-type and β-arrestin-2 knockout (KO) mice. SNC80, a β-arrestin-2 biased DOR agonist, increased alcohol intake in wild-type mice; however, SNC80 decreased alcohol intake in β-arrestin-2 KO mice, thus resulting in a behavioral outcome generally observed for Gi/o-biased agonists and suggesting that β-arrestin recruitment is required for SNC80-increased alcohol intake. Overall, these results suggest that activation Gi/o-coupled GPCRs expressed in the dorsal striatum, such as the DOR, by G-protein biased agonists may be a potential strategy to decrease voluntary alcohol consumption and β-arrestin recruitment is to be avoided.
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Affiliation(s)
- Meridith T Robins
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States.,Purdue University Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, United States
| | - Terrance Chiang
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States.,Purdue University Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, United States
| | - Kendall L Mores
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States
| | - Doungkamol Alongkronrusmee
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States.,Purdue University Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, United States
| | - Richard M van Rijn
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States.,Purdue University Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, United States
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21
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Gendron L, Cahill CM, von Zastrow M, Schiller PW, Pineyro G. Molecular Pharmacology of δ-Opioid Receptors. Pharmacol Rev 2017; 68:631-700. [PMID: 27343248 DOI: 10.1124/pr.114.008979] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Opioids are among the most effective analgesics available and are the first choice in the treatment of acute severe pain. However, partial efficacy, a tendency to produce tolerance, and a host of ill-tolerated side effects make clinically available opioids less effective in the management of chronic pain syndromes. Given that most therapeutic opioids produce their actions via µ-opioid receptors (MOPrs), other targets are constantly being explored, among which δ-opioid receptors (DOPrs) are being increasingly considered as promising alternatives. This review addresses DOPrs from the perspective of cellular and molecular determinants of their pharmacological diversity. Thus, DOPr ligands are examined in terms of structural and functional variety, DOPrs' capacity to engage a multiplicity of canonical and noncanonical G protein-dependent responses is surveyed, and evidence supporting ligand-specific signaling and regulation is analyzed. Pharmacological DOPr subtypes are examined in light of the ability of DOPr to organize into multimeric arrays and to adopt multiple active conformations as well as differences in ligand kinetics. Current knowledge on DOPr targeting to the membrane is examined as a means of understanding how these receptors are especially active in chronic pain management. Insight into cellular and molecular mechanisms of pharmacological diversity should guide the rational design of more effective, longer-lasting, and better-tolerated opioid analgesics for chronic pain management.
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Affiliation(s)
- Louis Gendron
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Catherine M Cahill
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Mark von Zastrow
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Peter W Schiller
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Graciela Pineyro
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
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Morrone LA, Scuteri D, Rombolà L, Mizoguchi H, Bagetta G. Opioids Resistance in Chronic Pain Management. Curr Neuropharmacol 2017; 15:444-456. [PMID: 28503117 PMCID: PMC5405610 DOI: 10.2174/1570159x14666161101092822] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Revised: 08/11/2016] [Accepted: 10/24/2016] [Indexed: 01/07/2023] Open
Abstract
Chronic pain management represents a serious healthcare problem worldwide. Chronic pain affects approximately 20% of the adult European population and is more frequent in women and older people. Unfortunately, its management in the community remains generally unsatisfactory and rarely under the control of currently available analgesics. Opioids have been used as analgesics for a long history and are among the most used drugs; however, while there is no debate over their short term use for pain management, limited evidence supports their efficacy of long-term treatment for chronic non-cancer pain. Therapy with opioids is hampered by inter-individual variability and serious side effects and some opioids often result ineffective in the treatment of chronic pain and their use is controversial. Accordingly, for a better control of chronic pain a deeper knowledge of the molecular mechanisms underlying resistance to opiates is mandatory.
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Affiliation(s)
- Luigi A. Morrone
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Rende, Italy
- University Consortium for Adaptive Disorders and Head Pain (UCADH), Section of Neuropharmacology of Normal and Pathological Neuronal Plasticity, University of Calabria, Rende, Italy
| | - Damiana Scuteri
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Rende, Italy
| | - Laura Rombolà
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Rende, Italy
| | - Hirokazu Mizoguchi
- Department of Physiology and Anatomy, Tohoku Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai 981-8558, Japan
| | - Giacinto Bagetta
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Rende, Italy
- University Consortium for Adaptive Disorders and Head Pain (UCADH), Section of Neuropharmacology of Normal and Pathological Neuronal Plasticity, University of Calabria, Rende, Italy
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23
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Brust TF, Alongkronrusmee D, Soto-Velasquez M, Baldwin TA, Ye Z, Dai M, Dessauer CW, van Rijn RM, Watts VJ. Identification of a selective small-molecule inhibitor of type 1 adenylyl cyclase activity with analgesic properties. Sci Signal 2017; 10:10/467/eaah5381. [PMID: 28223412 DOI: 10.1126/scisignal.aah5381] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Adenylyl cyclase 1 (AC1) belongs to a group of adenylyl cyclases (ACs) that are stimulated by calcium in a calmodulin-dependent manner. Studies with AC1 knockout mice suggest that inhibitors of AC1 may be useful for treating pain and opioid dependence. However, nonselective inhibition of AC isoforms could result in substantial adverse effects. We used chemical library screening to identify a selective AC1 inhibitor with a chromone core structure that may represent a new analgesic agent. After demonstrating that the compound (ST034307) inhibited Ca2+-stimulated adenosine 3',5'-monophosphate (cAMP) accumulation in human embryonic kidney (HEK) cells stably transfected with AC1 (HEK-AC1 cells), we confirmed selectivity for AC1 by testing against all isoforms of membrane-bound ACs. ST034307 also inhibited AC1 activity stimulated by forskolin- and Gαs-coupled receptors in HEK-AC1 cells and showed inhibitory activity in multiple AC1-containing membrane preparations and mouse hippocampal homogenates. ST034307 enhanced μ-opioid receptor (MOR)-mediated inhibition of AC1 in short-term inhibition assays in HEK-AC1 cells stably transfected with MOR; however, the compound blocked heterologous sensitization of AC1 caused by chronic MOR activation in these cells. ST034307 reduced pain responses in a mouse model of inflammatory pain. Our data indicate that ST034307 is a selective small-molecule inhibitor of AC1 and suggest that selective AC1 inhibitors may be useful for managing pain.
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Affiliation(s)
- Tarsis F Brust
- Department of Medicinal Chemistry and Molecular Pharmacology and Center for Drug Discovery, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, IN 47907, USA
| | - Doungkamol Alongkronrusmee
- Department of Medicinal Chemistry and Molecular Pharmacology and Center for Drug Discovery, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, IN 47907, USA
| | - Monica Soto-Velasquez
- Department of Medicinal Chemistry and Molecular Pharmacology and Center for Drug Discovery, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, IN 47907, USA
| | - Tanya A Baldwin
- Department of Integrative Biology and Pharmacology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Zhishi Ye
- Department of Chemistry and Centers for Cancer Research and Drug Discovery, College of Science, Purdue University, 720 Clinic Drive, West Lafayette, IN 47907, USA
| | - Mingji Dai
- Department of Chemistry and Centers for Cancer Research and Drug Discovery, College of Science, Purdue University, 720 Clinic Drive, West Lafayette, IN 47907, USA
| | - Carmen W Dessauer
- Department of Integrative Biology and Pharmacology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Richard M van Rijn
- Department of Medicinal Chemistry and Molecular Pharmacology and Center for Drug Discovery, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, IN 47907, USA
| | - Val J Watts
- Department of Medicinal Chemistry and Molecular Pharmacology and Center for Drug Discovery, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, IN 47907, USA.
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24
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Alongkronrusmee D, Chiang T, van Rijn RM. Involvement of delta opioid receptors in alcohol withdrawal-induced mechanical allodynia in male C57BL/6 mice. Drug Alcohol Depend 2016; 167:190-8. [PMID: 27567436 PMCID: PMC5325684 DOI: 10.1016/j.drugalcdep.2016.08.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 07/25/2016] [Accepted: 08/15/2016] [Indexed: 01/10/2023]
Abstract
BACKGROUND As a legal drug, alcohol is commonly abused and it is estimated that 17 million adults in the United States suffer from alcohol use disorder. Heavy alcoholics can experience withdrawal symptoms including anxiety and mechanical allodynia that can facilitate relapse. The molecular mechanisms underlying this phenomenon are not well understood, which stifles development of new therapeutics. Here we investigate whether delta opioid receptors (DORs) play an active role in alcohol withdrawal-induced mechanical allodynia (AWiMA) and if DOR agonists may provide analgesic relief from AWiMA. METHODS To study AWiMA, adult male wild-type and DOR knockout C57BL/6 mice were exposed to alcohol by a voluntary drinking model or oral gavage exposure model, which we developed and validated here. We also used the DOR-selective agonist TAN-67 and antagonist naltrindole to examine the involvement of DORs in AWiMA, which was measured using a von Frey model of mechanical allodynia. RESULTS We created a robust model of alcohol withdrawal-induced anxiety and mechanical allodynia by orally gavaging mice with 3g/kg alcohol for three weeks. AWiMA was exacerbated and prolonged in DOR knockout mice as well as by pharmacological blockade of DORs compared to control mice. However, analgesia induced by TAN-67 was attenuated during withdrawal in alcohol-gavaged mice. CONCLUSIONS DORs appear to play a protective role in the establishment of AWiMA. Our current results indicate that DORs could be targeted to prevent or reduce the development of AWiMA during alcohol use; however, DORs may be a less suitable target to treat AWiMA during active withdrawal.
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Affiliation(s)
- Doungkamol Alongkronrusmee
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana 47907
| | - Terrance Chiang
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana 47907
| | - Richard M. van Rijn
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana 47907,Corresponding author: Richard M. van Rijn;
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25
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Chiang T, Sansuk K, van Rijn RM. β-Arrestin 2 dependence of δ opioid receptor agonists is correlated with alcohol intake. Br J Pharmacol 2016; 173:332-43. [PMID: 26507558 DOI: 10.1111/bph.13374] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 09/30/2015] [Accepted: 10/11/2015] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND AND PURPOSE δ Opioid receptor agonists are being developed as potential treatments for depression and alcohol use disorders. This is particularly interesting as depression is frequently co-morbid with alcohol use disorders. Yet we have previously shown that δ receptor agonists range widely in their ability to modulate alcohol intake; certain δ receptor agonists actually increase alcohol consumption in mice. We propose that variations in β-arrestin 2 recruitment contribute to the differential behavioural profile of δ receptor agonists. EXPERIMENTAL APPROACH We used three diarylmethylpiperazine-based non-peptidic δ receptor selective agonists (SNC80, SNC162 and ARM390) and three structurally diverse δ receptor agonists (TAN-67, KNT127 and NIH11082). We tested these agonists in cAMP and β-arrestin 2 recruitment assays and a behavioural assay of alcohol intake in male C57BL/6 mice. We used β-arrestin 2 knockout mice and a model of depression-like behaviour to further study the role of β-arrestin 2 in δ receptor pharmacology. KEY RESULTS All six tested δ receptor agonists were full agonists in the cAMP assay but displayed distinct β-arrestin 2 recruitment efficacy. The efficacy of δ receptor agonists to recruit β-arrestin 2 positively correlated with their ability to increase alcohol intake (P < 0.01). The effects of the very efficacious recruiter SNC80 on alcohol intake, alcohol place preference and depression-like behaviour were β-arrestin 2-dependent. CONCLUSIONS AND IMPLICATIONS Our finding that δ receptor agonists that strongly recruit β-arrestin 2 can increase alcohol intake carries important ramifications for drug development of δ receptor agonists for treatment of alcohol use disorders and depressive disorders.
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Affiliation(s)
- T Chiang
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, USA
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26
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Vicente-Sanchez A, Segura L, Pradhan AA. The delta opioid receptor tool box. Neuroscience 2016; 338:145-159. [PMID: 27349452 DOI: 10.1016/j.neuroscience.2016.06.028] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 05/29/2016] [Accepted: 06/16/2016] [Indexed: 12/14/2022]
Abstract
In recent years, the delta opioid receptor has attracted increasing interest as a target for the treatment of chronic pain and emotional disorders. Due to their therapeutic potential, numerous tools have been developed to study the delta opioid receptor from both a molecular and a functional perspective. This review summarizes the most commonly available tools, with an emphasis on their use and limitations. Here, we describe (1) the cell-based assays used to study the delta opioid receptor. (2) The features of several delta opioid receptor ligands, including peptide and non-peptide drugs. (3) The existing approaches to detect delta opioid receptors in fixed tissue, and debates that surround these techniques. (4) Behavioral assays used to study the in vivo effects of delta opioid receptor agonists; including locomotor stimulation and convulsions that are induced by some ligands, but not others. (5) The characterization of genetically modified mice used specifically to study the delta opioid receptor. Overall, this review aims to provide a guideline for the use of these tools with the final goal of increasing our understanding of delta opioid receptor physiology.
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Affiliation(s)
| | - Laura Segura
- Department of Psychiatry, University of Illinois at Chicago, United States
| | - Amynah A Pradhan
- Department of Psychiatry, University of Illinois at Chicago, United States.
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27
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Alongkronrusmee D, Chiang T, van Rijn RM. Delta Opioid Pharmacology in Relation to Alcohol Behaviors. Handb Exp Pharmacol 2016; 247:199-225. [PMID: 27316912 DOI: 10.1007/164_2016_30] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Delta opioid receptors (DORs) are heavily involved in alcohol-mediated processes in the brain. In this chapter we provide an overview of studies investigating how alcohol directly impacts DOR pharmacology and of early studies indicating DOR modulation of alcohol behavior. We will offer a brief summary of the different animal species used in alcohol studies investigating DORs followed by a broader overview of the types of alcohol behaviors modulated by DORs. We will highlight a small set of studies investigating the relationship between alcohol and DORs in analgesia. We will then provide an anatomical overview linking DOR expression in specific brain regions to different alcohol behaviors. In this section, we will provide two models that try to explain how endogenous opioids acting at DORs may influence alcohol behaviors. Next, we will provide an overview of studies investigating certain new aspects of DOR pharmacology, including the formation of heteromers and biased signaling. Finally, we provide a short overview of the genetics of the DORs in relation to alcohol use disorders (AUDs) and a short statement on the potential of using DOR-based therapeutics for treatment of AUDs.
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Affiliation(s)
- Doungkamol Alongkronrusmee
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, USA
| | - Terrance Chiang
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, USA
| | - Richard M van Rijn
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, USA.
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28
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Dual allosteric modulation of opioid antinociceptive potency by α2A-adrenoceptors. Neuropharmacology 2015; 99:285-300. [PMID: 26254859 DOI: 10.1016/j.neuropharm.2015.08.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2014] [Revised: 07/09/2015] [Accepted: 08/04/2015] [Indexed: 12/31/2022]
Abstract
Opioid and α2-adrenoceptor (AR) agonists are analgesic when administered in the spinal cord and show a clinically beneficial synergistic interaction when co-administered. However, α2-AR antagonists can also inhibit opioid antinociception, suggesting a complex interaction between the two systems. The α2A-AR subtype is necessary for spinal adrenergic analgesia and synergy with opioids for most agonist combinations. Therefore, we investigated whether spinal opioid antinociception and opioid-adrenergic synergy were under allosteric control of the α2A-AR. Drugs were administered intrathecally in wild type (WT) and α2A-knock-out (KO) mice and antinociception was measured using the hot water tail immersion or substance P behavioral assays. The α2A-AR agonist clonidine was less effective in α2A-KO mice in both assays. The absence of the α2A-AR resulted in 10-70-fold increases in the antinociceptive potency of the opioid agonists morphine and DeltII. In contrast, neither morphine nor DeltII synergized with clonidine in α2A-KO mice, indicating that the α2AAR has both positive and negative modulatory effects on opioid antinociception. Depletion of descending adrenergic terminals with 6-OHDA resulted in a significant decrease in morphine efficacy in WT but not in α2A-KO mice, suggesting that endogenous norepinephrine acts through the α2A-AR to facilitate morphine antinociception. Based on these findings, we propose a model whereby ligand-occupied versus ligand-free α2A-AR produce distinct patterns of modulation of opioid receptor activation. In this model, agonist-occupied α2A-ARs potentiate opioid analgesia, while non-occupied α2A-ARs inhibit opioid analgesia. Exploiting such interactions between the two receptors could lead to the development of better pharmacological treatments for pain management.
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29
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Pradhan AA, Tawfik VL, Tipton AF, Scherrer G. In vivo techniques to investigate the internalization profile of opioid receptors. Methods Mol Biol 2015; 1230:87-104. [PMID: 25293318 DOI: 10.1007/978-1-4939-1708-2_7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
G-protein-coupled receptors (GPCRs) regulate a remarkable diversity of biological functions, and are thus often targeted for drug therapies. Receptor internalization is commonly observed following agonist binding and activation. Receptor trafficking events have been well characterized in cell systems, but the in vivo significance of GPCR internalization is still poorly understood. To address this issue, we have developed an innovative knock-in mouse model, where an opioid receptor is directly visible in vivo. These knockin mice express functional fluorescent delta opioid receptors (DOR-eGFP) in place of the endogenous receptor, and these receptors are expressed at physiological levels within their native environment. DOR-eGFP mice have proven to be an extraordinary tool in studying receptor neuroanatomy, real-time receptor trafficking in live neurons, and in vivo receptor internalization. We have used this animal model to determine the relationship between receptor trafficking in neurons and receptor function at a behavioral level. Here, we describe in detail the construction and characterization of this knockin mouse. We also outline how to use these mice to examine the behavioral consequences of agonist-specific trafficking at the delta opioid receptor. These techniques are potentially applicable to any GPCR, and highlight the powerful nature of this imaging tool.
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Affiliation(s)
- Amynah A Pradhan
- Department of Psychiatry, University of Illinois at Chicago, 1601 W Taylor Street, Chicago, IL, 60612, USA,
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30
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Taylor AMW, Roberts KW, Pradhan AA, Akbari HA, Walwyn W, Lutfy K, Carroll FI, Cahill CM, Evans CJ. Anti-nociception mediated by a κ opioid receptor agonist is blocked by a δ receptor agonist. Br J Pharmacol 2014; 172:691-703. [PMID: 24923251 PMCID: PMC4292979 DOI: 10.1111/bph.12810] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 05/23/2014] [Accepted: 06/06/2014] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND AND PURPOSE The opioid receptor family comprises four structurally homologous but functionally distinct sub-groups, the μ (MOP), δ (DOP), κ (KOP) and nociceptin (NOP) receptors. As most opioid agonists are selective but not specific, a broad spectrum of behaviours due to activation of different opioid receptors is expected. In this study, we examine whether other opioid receptor systems influenced KOP-mediated antinociception. EXPERIMENTAL APPROACH We used a tail withdrawal assay in C57Bl/6 mice to assay the antinociceptive effect of systemically administered opioid agonists with varying selectivity at KOP receptors. Pharmacological and genetic approaches were used to analyse the interactions of the other opioid receptors in modulating KOP-mediated antinociception. KEY RESULTS Etorphine, a potent agonist at all four opioid receptors, was not anti-nociceptive in MOP knockout (KO) mice, although etorphine is an efficacious KOP receptor agonist and specific KOP receptor agonists remain analgesic in MOP KO mice. As KOP receptor agonists are aversive, we considered KOP-mediated antinociception might be a form of stress-induced analgesia that is blocked by the anxiolytic effects of DOP receptor agonists. In support of this hypothesis, pretreatment with the DOP antagonist, naltrindole (10 mg·kg(-1) ), unmasked etorphine (3 mg·kg(-1) ) antinociception in MOP KO mice. Further, in wild-type mice, KOP-mediated antinociception by systemic U50,488H (10 mg·kg(-1) ) was blocked by pretreatment with the DOP agonist SNC80 (5 mg·kg(-1) ) and diazepam (1 mg·kg(-1) ). CONCLUSIONS AND IMPLICATIONS Systemic DOP receptor agonists blocked systemic KOP antinociception, and these results identify DOP receptor agonists as potential agents for reversing stress-driven addictive and depressive behaviours mediated through KOP receptor activation. LINKED ARTICLES This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2.
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Affiliation(s)
- A M W Taylor
- University of California, Los Angeles, CA, USA; University of California Irvine, Irvine, CA, USA
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31
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Zhang X, Bao L, Li S. Opioid receptor trafficking and interaction in nociceptors. Br J Pharmacol 2014; 172:364-74. [PMID: 24611685 DOI: 10.1111/bph.12653] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Revised: 01/29/2014] [Accepted: 02/17/2014] [Indexed: 01/15/2023] Open
Abstract
UNLABELLED Opiate analgesics such as morphine are often used for pain therapy. However, antinociceptive tolerance and dependence may develop with long-term use of these drugs. It was found that μ-opioid receptors can interact with δ-opioid receptors, and morphine antinociceptive tolerance can be reduced by blocking δ-opioid receptors. Recent studies have shown that μ- and δ-opioid receptors are co-expressed in a considerable number of small neurons in the dorsal root ganglion. The interaction of μ-opioid receptors with δ-opioid receptors in the nociceptive afferents is facilitated by the stimulus-induced cell-surface expression of δ-opioid receptors, and contributes to morphine tolerance. Further analysis of the molecular, cellular and neural circuit mechanisms that regulate the trafficking and interaction of opioid receptors and related signalling molecules in the pain pathway would help to elucidate the mechanism of opiate analgesia and improve pain therapy. LINKED ARTICLES This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2.
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Affiliation(s)
- X Zhang
- Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai, China
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32
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Klenowski P, Morgan M, Bartlett SE. The role of δ-opioid receptors in learning and memory underlying the development of addiction. Br J Pharmacol 2014; 172:297-310. [PMID: 24641428 DOI: 10.1111/bph.12618] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Revised: 01/10/2014] [Accepted: 01/19/2014] [Indexed: 01/14/2023] Open
Abstract
UNLABELLED Opioids are important endogenous ligands that exist in both invertebrates and vertebrates and signal by activation of opioid receptors to produce analgesia and reward or pleasure. The μ-opioid receptor is the best known of the opioid receptors and mediates the acute analgesic effects of opiates, while the δ-opioid receptor (DOR) has been less well studied and has been linked to effects that follow from chronic use of opiates such as stress, inflammation and anxiety. Recently, DORs have been shown to play an essential role in emotions and increasing evidence points to a role in learning actions and outcomes. The process of learning and memory in addiction has been proposed to involve strengthening of specific brain circuits when a drug is paired with a context or environment. The DOR is highly expressed in the hippocampus, amygdala, striatum and other basal ganglia structures known to participate in learning and memory. In this review, we will focus on the role of the DOR and its potential role in learning and memory underlying the development of addiction. LINKED ARTICLES This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2.
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Affiliation(s)
- Paul Klenowski
- Translational Research Institute, Institute for Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia
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33
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Sacharczuk M, Lesniak A, Lipkowski AW, Korostynski M, Przewlocki R, Sadowski B. Association between the A107V substitution in the δ-opioid receptors and ethanol drinking in mice selected for high and low analgesia. Addict Biol 2014; 19:643-51. [PMID: 23301597 DOI: 10.1111/adb.12030] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Experimental evidence suggests that endogenous opioids play an important role in the development of ethanol addiction. In this study, we employed two mouse lines divergently bred for opioid-mediated stress-induced analgesia. In comparison with HA (high analgesia line) mice, LA (low analgesia line) mice, having lower opioid receptor system activity, manifest enhanced basal as well as stress-induced ethanol drinking. Here, we found that recently discovered C320T transition in exon 2 of the δ-opioid receptor gene (EU446125.1), which results in an A107V substitution (ACA23171.1), leads to higher ethanol preference in CT mice compared with CC homozygotes. This genetic association is particularly evident under chronic mild stress (CMS) conditions. The interaction between stress and ethanol intake was significantly stronger in HA than in LA mice. Ethanol almost completely attenuated the pro-depressive effect of CMS (assessed with the tail suspension test) in both the CC and CT genotypes in the HA line. In the LA mice, a lack of response to ethanol was observed in the CC genotype, whereas ethanol consumption strengthened depressive-like behaviours in CT individuals. Our results suggest that constitutively active A107V substitution in δ-opioid receptors may be involved in stress-enhanced vulnerability to ethanol abuse and in the risk of ethanol dependence.
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Affiliation(s)
- Mariusz Sacharczuk
- Department of Molecular Cytogenetics, Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Poland
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Chabot-Doré AJ, Schuster DJ, Stone LS, Wilcox GL. Analgesic synergy between opioid and α2 -adrenoceptors. Br J Pharmacol 2014; 172:388-402. [PMID: 24641506 DOI: 10.1111/bph.12695] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2013] [Revised: 03/08/2014] [Accepted: 03/12/2014] [Indexed: 12/24/2022] Open
Abstract
UNLABELLED Opioid and α2 -adrenoceptor agonists are potent analgesic drugs and their analgesic effects can synergize when co-administered. These supra-additive interactions are potentially beneficial clinically; by increasing efficacy and/or reducing the total drug required to produce sufficient pain relief, undesired side effects can be minimized. However, combination therapies of opioids and α2 -adrenoceptor agonists remain underutilized clinically, in spite of a large body of preclinical evidence describing their synergistic interaction. One possible obstacle to the translation of preclinical findings to clinical applications is a lack of understanding of the mechanisms underlying the synergistic interactions between these two drug classes. In this review, we provide a detailed overview of the interactions between different opioid and α2 -adrenoceptor agonist combinations in preclinical studies. These studies have identified the spinal cord as an important site of action of synergistic interactions, provided insights into which receptors mediate these interactions and explored downstream signalling events enabling synergy. It is now well documented that the activation of both μ and δ opioid receptors can produce synergy with α2 -adrenoceptor agonists and that α2 -adrenoceptor agonists can mediate synergy through either the α2A or the α2C adrenoceptor subtypes. Current hypotheses surrounding the cellular mechanisms mediating opioid-adrenoceptor synergy, including PKC signalling and receptor oligomerization, and the evidence supporting them are presented. Finally, the implications of these findings for clinical applications and drug discovery are discussed. LINKED ARTICLES This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2.
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Affiliation(s)
- A-J Chabot-Doré
- Alan Edwards Centre for Research on Pain, McGill University, Montreal, QC, Canada; Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
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Gendron L, Mittal N, Beaudry H, Walwyn W. Recent advances on the δ opioid receptor: from trafficking to function. Br J Pharmacol 2014; 172:403-19. [PMID: 24665909 DOI: 10.1111/bph.12706] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 03/17/2014] [Accepted: 03/18/2014] [Indexed: 01/12/2023] Open
Abstract
UNLABELLED Within the opioid family of receptors, δ (DOPrs) and μ opioid receptors (MOPrs) are typical GPCRs that activate canonical second-messenger signalling cascades to influence diverse cellular functions in neuronal and non-neuronal cell types. These receptors activate well-known pathways to influence ion channel function and pathways such as the map kinase cascade, AC and PI3K. In addition new information regarding opioid receptor-interacting proteins, downstream signalling pathways and resultant functional effects has recently come to light. In this review, we will examine these novel findings focusing on the DOPr and, in doing so, will contrast and compare DOPrs with MOPrs in terms of differences and similarities in function, signalling pathways, distribution and interactions. We will also discuss and clarify issues that have recently surfaced regarding the expression and function of DOPrs in different cell types and analgesia. LINKED ARTICLES This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2.
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Affiliation(s)
- Louis Gendron
- Département de physiologie et biophysique, Institut de pharmacologie de Sherbrooke, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, QC, Canada
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DOR2-selective but not DOR1-selective antagonist abolishes anxiolytic-like effects of the δ opioid receptor agonist KNT-127. Neuropharmacology 2014; 79:314-20. [DOI: 10.1016/j.neuropharm.2013.11.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Revised: 11/06/2013] [Accepted: 11/23/2013] [Indexed: 01/02/2023]
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Bardoni R, Tawfik VL, Wang D, François A, Solorzano C, Shuster SA, Choudhury P, Betelli C, Cassidy C, Smith K, de Nooij JC, Mennicken F, O'Donnell D, Kieffer BL, Woodbury CJ, Basbaum AI, MacDermott AB, Scherrer G. Delta opioid receptors presynaptically regulate cutaneous mechanosensory neuron input to the spinal cord dorsal horn. Neuron 2014; 81:1312-1327. [PMID: 24583022 DOI: 10.1016/j.neuron.2014.01.044] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/16/2014] [Indexed: 11/24/2022]
Abstract
Cutaneous mechanosensory neurons detect mechanical stimuli that generate touch and pain sensation. Although opioids are generally associated only with the control of pain, here we report that the opioid system in fact broadly regulates cutaneous mechanosensation, including touch. This function is predominantly subserved by the delta opioid receptor (DOR), which is expressed by myelinated mechanoreceptors that form Meissner corpuscles, Merkel cell-neurite complexes, and circumferential hair follicle endings. These afferents also include a small population of CGRP-expressing myelinated nociceptors that we now identify as the somatosensory neurons that coexpress mu and delta opioid receptors. We further demonstrate that DOR activation at the central terminals of myelinated mechanoreceptors depresses synaptic input to the spinal dorsal horn, via the inhibition of voltage-gated calcium channels. Collectively our results uncover a molecular mechanism by which opioids modulate cutaneous mechanosensation and provide a rationale for targeting DOR to alleviate injury-induced mechanical hypersensitivity.
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Affiliation(s)
- Rita Bardoni
- Department of Biomedical, Metabolic and Neural Science, University of Modena and Reggio Emilia, 41100 Modena, Italy
| | - Vivianne L Tawfik
- Department of Anesthesiology, Perioperative and Pain Medicine, Department of Molecular and Cellular Physiology, Stanford Neurosciences Institute, Stanford University, Palo Alto, CA 94304, USA
| | - Dong Wang
- Department of Anesthesiology, Perioperative and Pain Medicine, Department of Molecular and Cellular Physiology, Stanford Neurosciences Institute, Stanford University, Palo Alto, CA 94304, USA
| | - Amaury François
- Department of Anesthesiology, Perioperative and Pain Medicine, Department of Molecular and Cellular Physiology, Stanford Neurosciences Institute, Stanford University, Palo Alto, CA 94304, USA
| | - Carlos Solorzano
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Scott A Shuster
- Department of Anesthesiology, Perioperative and Pain Medicine, Department of Molecular and Cellular Physiology, Stanford Neurosciences Institute, Stanford University, Palo Alto, CA 94304, USA
| | - Papiya Choudhury
- Department of Physiology and Cellular Biophysics, Department of Neuroscience, Columbia University, New York, NY 10032, USA
| | - Chiara Betelli
- Department of Biomedical, Metabolic and Neural Science, University of Modena and Reggio Emilia, 41100 Modena, Italy
| | - Colleen Cassidy
- Graduate Program in Neuroscience, University of Wyoming, Laramie, WY 82071, USA; Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA
| | - Kristen Smith
- Graduate Program in Neuroscience, University of Wyoming, Laramie, WY 82071, USA; Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA
| | - Joriene C de Nooij
- Departments of Neuroscience and Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Françoise Mennicken
- AstraZeneca R&D Montreal, Department of Translational Science, Montreal, QC H4S 1Z9, Canada
| | - Dajan O'Donnell
- AstraZeneca R&D Montreal, Department of Translational Science, Montreal, QC H4S 1Z9, Canada
| | - Brigitte L Kieffer
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, UMR7104 CNRS/Université de Strasbourg, U964 INSERM, 67400 Illkirch, France
| | - C Jeffrey Woodbury
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA
| | - Allan I Basbaum
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Amy B MacDermott
- Department of Physiology and Cellular Biophysics, Department of Neuroscience, Columbia University, New York, NY 10032, USA
| | - Grégory Scherrer
- Department of Anesthesiology, Perioperative and Pain Medicine, Department of Molecular and Cellular Physiology, Stanford Neurosciences Institute, Stanford University, Palo Alto, CA 94304, USA.
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Abstract
This paper is the thirty-fifth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2012 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurologic disorders (Section 11); electrical-related activity and neurophysiology (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration and thermoregulation (Section 16); and immunological responses (Section 17).
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, Flushing, NY 11367, United States.
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Chabot-Doré AJ, Millecamps M, Stone LS. The Delta-Opioid Receptor Is Sufficient, but Not Necessary, for Spinal Opioid-Adrenergic Analgesic Synergy. J Pharmacol Exp Ther 2013; 347:773-80. [DOI: 10.1124/jpet.113.206581] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
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Normandin A, Luccarini P, Molat JL, Gendron L, Dallel R. Spinal μ and δ opioids inhibit both thermal and mechanical pain in rats. J Neurosci 2013; 33:11703-14. [PMID: 23843537 PMCID: PMC3855450 DOI: 10.1523/jneurosci.1631-13.2013] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Revised: 06/04/2013] [Accepted: 06/07/2013] [Indexed: 11/21/2022] Open
Abstract
The expression and contribution of μ (MOPR) and δ opioid receptors (DOPR) in polymodal nociceptors have been recently challenged. Indeed, MOPR and DOPR were shown to be expressed in distinct subpopulation of nociceptors where they inhibit pain induced by noxious heat and mechanical stimuli, respectively. In the present study, we used electrophysiological measurements to assess the effect of spinal MOPR and DOPR activation on heat-induced and mechanically induced diffuse noxious inhibitory controls (DNICs). We recorded from wide dynamic range neurons in the spinal trigeminal nucleus of anesthetized rats. Trains of 105 electrical shocks were delivered to the excitatory cutaneous receptive field. DNICs were triggered either by immersion of the hindpaw in 49°C water or application of 300 g of mechanical pressure. To study the involvement of peptidergic primary afferents in the activation of DNIC by noxious heat and mechanical stimulations, substance P release was measured in the spinal cord by visualizing neurokinin type 1 receptor internalization. We found that the activation of spinal MOPR and DOPR similarly attenuates the DNIC and neurokinin type 1 receptor internalization induced either by heat or mechanical stimuli. Our results therefore reveal that the activation of spinal MOPR and DOPR relieves both heat-induced and mechanically induced pain with similar potency and suggest that these receptors are expressed on polymodal, substance P-expressing neurons.
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Affiliation(s)
- Audrey Normandin
- Département de physiologie et biophysique, Faculté de médecine et des sciences de la santé
| | - Philippe Luccarini
- Clermont Université, Université d'Auvergne, NEURO-DOL, BP 10448, F-63000, CLERMONT-FERRAND Inserm, U1107, F-63001 Clermont-Ferrand, France
| | - Jean-Louis Molat
- Clermont Université, Université d'Auvergne, NEURO-DOL, BP 10448, F-63000, CLERMONT-FERRAND Inserm, U1107, F-63001 Clermont-Ferrand, France
| | - Louis Gendron
- Département de physiologie et biophysique, Faculté de médecine et des sciences de la santé
- Institut de pharmacologie de Sherbrooke, and
- Centre de recherche clinique Étienne-Le Bel, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada, and
| | - Radhouane Dallel
- Clermont Université, Université d'Auvergne, NEURO-DOL, BP 10448, F-63000, CLERMONT-FERRAND Inserm, U1107, F-63001 Clermont-Ferrand, France
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Pharmacological traits of delta opioid receptors: pitfalls or opportunities? Psychopharmacology (Berl) 2013; 228:1-18. [PMID: 23649885 PMCID: PMC3679311 DOI: 10.1007/s00213-013-3129-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Accepted: 04/15/2013] [Indexed: 12/11/2022]
Abstract
RATIONALE Delta opioid receptors (DORs) have been considered as a potential target to relieve pain as well as treat depression and anxiety disorders and are known to modulate other physiological responses, including ethanol and food consumption. A small number of DOR-selective drugs are in clinical trials, but no DOR-selective drugs have been approved by the Federal Drug Administration and some candidates have failed in phase II clinical trials, highlighting current difficulties producing effective delta opioid-based therapies. Recent studies have provided new insights into the pharmacology of the DOR, which is often complex and at times paradoxical. OBJECTIVE This review will discuss the existing literature focusing on four aspects: (1) Two DOR subtypes have been postulated based on differences in pharmacological effects of existing DOR-selective ligands. (2) DORs are expressed ubiquitously throughout the body and central nervous system and are, thus, positioned to play a role in a multitude of diseases. (3) DOR expression is often dynamic, with many reports of increased expression during exposure to chronic stimuli, such as stress, inflammation, neuropathy, morphine, or changes in endogenous opioid tone. (4) A large structural variety in DOR ligands implies potential different mechanisms of activating the receptor. CONCLUSION The reviewed features of DOR pharmacology illustrate the potential benefit of designing tailored or biased DOR ligands.
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Pradhan A, Smith M, McGuire B, Evans C, Walwyn W. Chronic inflammatory injury results in increased coupling of delta opioid receptors to voltage-gated Ca2+ channels. Mol Pain 2013; 9:8. [PMID: 23497324 PMCID: PMC3621800 DOI: 10.1186/1744-8069-9-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 02/25/2013] [Indexed: 12/31/2022] Open
Abstract
Background Opioid receptors regulate a diverse array of physiological functions. Mu opioid receptor agonists are well-known analgesics for treating acute pain. In contrast, animal models suggest that chronic pain is more effectively relieved by delta opioid receptor agonists. A number of studies have shown that chronic pain results in increased function of delta opioid receptors. This is proposed to result from enhanced trafficking of the delta opioid receptor to the cell membrane induced by persistent tissue injury. However, recent studies have questioned this mechanism, which has resulted in some uncertainty as to whether delta opioid receptors are indeed upregulated in chronic pain states. To clarify this question, we have examined the effect of chronic inflammatory pain over time using both an ex vivo measure of delta function: receptor-Ca2+ channel coupling, and an in vivo measure; the relief of chronic pain by a delta opioid receptor agonist. In addition, as beta-arrestin 2 can regulate delta opioid receptor trafficking and signaling, we have further examined whether deleting this scaffolding and signal transduction molecule alters delta opioid receptor function. Results We used the Complete Freund’s Adjuvant model of inflammatory pain, and examined the effectiveness of the delta agonist, SNC80, to both inhibit Ca2+ channels in primary afferent neurons and to attenuate mechanical allodynia. In naïve beta-arrestin 2 wildtype and knockout mice, SNC80 neither significantly inhibited voltage-dependent Ca2+ currents nor produced antinociception. However, following inflammatory pain, both measures showed a significant and long-lasting enhancement of delta opioid receptor function that persisted for up to 14 days post-injury regardless of genotype. Furthermore, although this pain model did not alter Ca2+ current density, the contribution of N-type Ca2+ channels to the total current appeared to be regulated by the presence of beta-arrestin 2. Conclusions Our results indicate that there is an upregulation of delta opioid receptor function following chronic pain. This gain of function is reflected in the increased efficacy of a delta agonist in both behavioral and electrophysiological measures. Overall, this work confirms that delta opioid receptors can be enhanced following tissue injury associated with chronic pain.
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Affiliation(s)
- Amynah Pradhan
- Department of Neuropsychiatry and Biobehavioral Sciences, Stefan and Shirley Hatos Center for Neuropharmacology, Semel Institute, University of California, Los Angeles, CA 90095, USA
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Roussotte FF, Jahanshad N, Hibar DP, Sowell ER, Kohannim O, Barysheva M, Hansell NK, McMahon KL, de Zubicaray GI, Montgomery GW, Martin NG, Wright MJ, Toga AW, Jack CR, Weiner MW, Thompson PM. A commonly carried genetic variant in the delta opioid receptor gene, OPRD1, is associated with smaller regional brain volumes: replication in elderly and young populations. Hum Brain Mapp 2013; 35:1226-36. [PMID: 23427138 DOI: 10.1002/hbm.22247] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Revised: 11/01/2012] [Accepted: 11/30/2012] [Indexed: 02/02/2023] Open
Abstract
Delta opioid receptors are implicated in a variety of psychiatric and neurological disorders. These receptors play a key role in the reinforcing properties of drugs of abuse, and polymorphisms in OPRD1 (the gene encoding delta opioid receptors) are associated with drug addiction. Delta opioid receptors are also involved in protecting neurons against hypoxic and ischemic stress. Here, we first examined a large sample of 738 elderly participants with neuroimaging and genetic data from the Alzheimer's Disease Neuroimaging Initiative. We hypothesized that common variants in OPRD1 would be associated with differences in brain structure, particularly in regions relevant to addictive and neurodegenerative disorders. One very common variant (rs678849) predicted differences in regional brain volumes. We replicated the association of this single-nucleotide polymorphism with regional tissue volumes in a large sample of young participants in the Queensland Twin Imaging study. Although the same allele was associated with reduced volumes in both cohorts, the brain regions affected differed between the two samples. In healthy elderly, exploratory analyses suggested that the genotype associated with reduced brain volumes in both cohorts may also predict cerebrospinal fluid levels of neurodegenerative biomarkers, but this requires confirmation. If opiate receptor genetic variants are related to individual differences in brain structure, genotyping of these variants may be helpful when designing clinical trials targeting delta opioid receptors to treat neurological disorders.
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Affiliation(s)
- Florence F Roussotte
- Imaging Genetics Center, Laboratory of Neuro Imaging, Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, California; Department of Pediatrics, Developmental Cognitive Neuroimaging Laboratory (DCNL), University of Southern California, Los Angeles, California
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Interaction and regulatory functions of μ- and δ-opioid receptors in nociceptive afferent neurons. Neurosci Bull 2012; 28:121-30. [PMID: 22466123 DOI: 10.1007/s12264-012-1206-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
μ-opioid receptor (MOR) agonists such as morphine are powerful analgesics used for pain therapy. However, the use of these drugs is limited by their side-effects, which include antinociceptive tolerance and dependence. Earlier studies reported that MOR analgesic tolerance is reduced by blockade of δ-opioid receptors (DORs) that interact with MORs. Recent studies show that the MOR/DOR interaction in nociceptive afferent neurons in the dorsal root ganglion may contribute to morphine analgesic tolerance. Further analysis of the mechanisms for regulating the trafficking of receptors, ion channels and signaling molecules in nociceptive afferent neurons would help to understand the nociceptive mechanisms and improve pain therapy.
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Harvey JH, Long DH, England PM, Whistler JL. Tuned-Affinity Bivalent Ligands for the Characterization of Opioid Receptor Heteromers. ACS Med Chem Lett 2012; 3:640-644. [PMID: 23585918 DOI: 10.1021/ml300083p] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Opioid receptors, including the mu and delta opioid receptors (MOR and DOR) are important targets for the treatment of pain. Although there is mounting evidence that these receptors form heteromers, the functional role of the MOR/DOR heteromer remains unresolved. We have designed and synthesized bivalent ligands as tools to elucidate the functional role of the MOR/DOR heteromer. Our ligands (L2 and L4) are comprised of a compound with low affinity at the DOR tethered to a compound with high affinity at the MOR, with the goal of producing ligands with "tuned affinity" at MOR/DOR heteromers compared to DOR homomers. Here we show that both L2 and L4 demonstrate enhanced affinity at MOR/DOR heteromers compared to DOR homomers, thereby providing unique pharmacological tools to dissect the role of the MOR/DOR heteromer in pain.
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Affiliation(s)
- Jessica H. Harvey
- Ernest Gallo Clinic and Research Center, 5858 Horton Street, Suite 200,
Emeryville, California 94608, United States
- University of California, San Francisco, Genentech Hall, 600 16th Street, San
Francisco, California 94158, United States
| | - Darcie H. Long
- Ernest Gallo Clinic and Research Center, 5858 Horton Street, Suite 200,
Emeryville, California 94608, United States
| | - Pamela M. England
- University of California, San Francisco, Genentech Hall, 600 16th Street, San
Francisco, California 94158, United States
| | - Jennifer L. Whistler
- Ernest Gallo Clinic and Research Center, 5858 Horton Street, Suite 200,
Emeryville, California 94608, United States
- University of California, San Francisco, Genentech Hall, 600 16th Street, San
Francisco, California 94158, United States
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van Rijn RM, Brissett DI, Whistler JL. Distinctive modulation of ethanol place preference by delta opioid receptor-selective agonists. Drug Alcohol Depend 2012; 122:156-9. [PMID: 22018601 PMCID: PMC3279630 DOI: 10.1016/j.drugalcdep.2011.09.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2011] [Revised: 09/16/2011] [Accepted: 09/22/2011] [Indexed: 10/16/2022]
Abstract
BACKGROUND Naltrexone is one of the few drugs approved by the Federal Drug Administration for the treatment of alcoholism. However, naltrexone is only effective in a subpopulation of treatment-seeking alcohol abusers, and suffers from compliance issues. The non-selective nature of this opioid antagonist likely contributes to its side effects and poor therapeutic efficacy. Drugs selectively targeting delta opioid receptor subtypes offer a potential way to treat alcohol abuse disorders. We have recently shown that delta subtype-selective agonists TAN-67 and SNC80 can have opposing effects on alcohol consumption, while having similar effects on alcohol withdrawal-induced anxiety. METHODS We studied the ability of TAN-67 and SNC80 to induce place preference in naïve and ethanol exposed C57BL/6 mice and determined the effect of these agonists on the expression of ethanol place preference. RESULTS We show that TAN-67 and SNC80 have opposing actions on ethanol place preference. However, neither of the drugs induces place preference by themselves at doses that are therapeutically effective in mice. Interestingly, SNC80, like naltrexone reduces ethanol place preference, however we have previously shown that SNC80 increases ethanol consumption at the tested dose. Similar to naltrexone, TAN-67 reduces alcohol consumption, but we show here that it may be due to an increase in ethanol place preference. Importantly, we found that chronic ethanol exposure does not increase the rewarding properties of the DOR subtype selective agonists. CONCLUSIONS Our results provide a better understanding of how DOR subtype selective drugs could potentially be used for treatment of alcohol abuse disorders.
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Affiliation(s)
- Richard M. van Rijn
- Corresponding author: Ernest Gallo Clinic and Research Center, Dept. of Neurology, University of California, San Francisco, 5858 Horton St., Suite 200, Emeryville, CA 94608. Tel.: 510-985-3131; Fax: 510-985-3101;
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Brissett DI, Whistler JL, van Rijn RM. Contribution of mu and delta opioid receptors to the pharmacological profile of kappa opioid receptor subtypes. Eur J Pain 2011; 16:327-37. [PMID: 22337177 DOI: 10.1002/j.1532-2149.2011.00022.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/03/2011] [Indexed: 12/12/2022]
Abstract
Molecular cloning has identified three opioid receptors: mu (MOR), delta (DOR) and kappa (KOR). Yet, cloning of these receptor types has offered little clarification to the diverse pharmacological profiles seen within the growing number of novel opioid ligands, which has led to the proposal of multiple subtypes. In the present study, utilizing in vitro and in vivo methods including the use of opioid receptor knockout mice, we find that certain antinociceptive effects of the KOR-1 and KOR-2 subtype-selective ligands (+)-(5α,7α,8β)-N-Methyl-N-[7-(1-pyrrolidinyl)-1-oxaspiro[4.5]dec-8-yl]-benzene-acetamide (U69, 593) and 4-[(3,4-Dichlorophenyl)acetyl]-3-(1-pyrrolidinylmethyl)-1-piperazine-carboxylic acid methyl ester fumarate (GR89, 696), respectively, are potentiated by antagonism of MOR and DOR receptors. We believe that our findings can be best explained by the existence of KOR-DOR and KOR-MOR heteromers. We only find evidence for the existence of these heteromers in neurons mediating mechanical nociception, but not thermal nociception. These findings have important clinical ramifications as they reveal new drug targets that may provide avenues for more effective pain therapies.
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Affiliation(s)
- D I Brissett
- Ernest Gallo Clinic and Research Center, Department of Neurology, University of California, San Francisco, Emeryville, CA 94608, USA
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