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Kise R, Inoue A. GPCR signaling bias: an emerging framework for opioid drug development. J Biochem 2024; 175:367-376. [PMID: 38308136 DOI: 10.1093/jb/mvae013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 01/18/2024] [Accepted: 01/31/2024] [Indexed: 02/04/2024] Open
Abstract
Biased signaling, also known as functional selectivity, has emerged as an important concept in drug development targeting G-protein-coupled receptors (GPCRs). Drugs that provoke biased signaling are expected to offer an opportunity for enhanced therapeutic effectiveness with minimized side effects. Opioid analgesics, whilst exerting potent pain-relieving effects, have become a social problem owing to their serious side effects. For the development of safer pain medications, there has been extensive exploration of agonists with a distinct balance of G-protein and β-arrestin (βarr) signaling. Recently, several approaches based on protein-protein interactions have been developed to precisely evaluate individual signal pathways, paving the way for the comprehensive analysis of biased signals. In this review, we describe an overview of bias signaling in opioid receptors, especially the μ-opioid receptor (MOR), and how to evaluate signaling bias in the GPCR field. We also discuss future directions for rational drug development through the integration of diverse signal datasets.
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Affiliation(s)
- Ryoji Kise
- Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3, Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8578, Japan
| | - Asuka Inoue
- Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3, Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8578, Japan
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2
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Ramos‐Gonzalez N, Groom S, Sutcliffe KJ, Bancroft S, Bailey CP, Sessions RB, Henderson G, Kelly E. Carfentanil is a β-arrestin-biased agonist at the μ opioid receptor. Br J Pharmacol 2023; 180:2341-2360. [PMID: 37005796 PMCID: PMC10952505 DOI: 10.1111/bph.16084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 03/10/2023] [Accepted: 03/28/2023] [Indexed: 04/04/2023] Open
Abstract
BACKGROUND AND PURPOSE The illicit use of fentanyl-like drugs (fentanyls), which are μ opioid receptor agonists, and the many overdose deaths that result, has become a major problem. Fentanyls are very potent in vivo, leading to respiratory depression and death. However, the efficacy and possible signalling bias of different fentanyls is not clearly known. Here, we compared the relative efficacy and bias of a series of fentanyls. EXPERIMENTAL APPROACH For agonist signalling bias and efficacy measurements, Bioluminescence Resonance Energy Transfer experiments were undertaken in HEK293T cells transiently transfected with μ opioid receptors, to assess Gi protein activation and β-arrestin 2 recruitment. Agonist-induced cell surface receptor loss was assessed using an enzyme-linked immunosorbent assay, whilst agonist-induced G protein-coupled inwardly rectifying potassium channel current activation was measured electrophysiologically from rat locus coeruleus slices. Ligand poses in the μ opioid receptor were determined in silico using molecular dynamics simulations. KEY RESULTS Relative to the reference ligand DAMGO, carfentanil was β-arrestin-biased, whereas fentanyl, sufentanil and alfentanil did not display bias. Carfentanil induced potent and extensive cell surface receptor loss, whilst the marked desensitisation of G protein-coupled inwardly rectifying potassium channel currents in the continued presence of carfentanil in neurones was prevented by a GRK2/3 inhibitor. Molecular dynamics simulations suggested unique interactions of carfentanil with the orthosteric site of the receptor that could underlie the bias. CONCLUSIONS AND IMPLICATIONS Carfentanil is a β-arrestin-biased opioid drug at the μ receptor. It is uncertain how such bias influences in vivo effects of carfentanil relative to other fentanyls.
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Affiliation(s)
| | - Sam Groom
- Department of Pharmacy and PharmacologyUniversity of BathBathUK
| | - Katy J. Sutcliffe
- School of Physiology, Pharmacology and NeuroscienceUniversity of BristolBristolUK
| | - Sukhvinder Bancroft
- School of Physiology, Pharmacology and NeuroscienceUniversity of BristolBristolUK
| | - Chris P. Bailey
- Department of Pharmacy and PharmacologyUniversity of BathBathUK
| | | | - Graeme Henderson
- School of Physiology, Pharmacology and NeuroscienceUniversity of BristolBristolUK
| | - Eamonn Kelly
- School of Physiology, Pharmacology and NeuroscienceUniversity of BristolBristolUK
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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] [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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Kelly E, Conibear A, Henderson G. Biased Agonism: Lessons from Studies of Opioid Receptor Agonists. Annu Rev Pharmacol Toxicol 2023; 63:491-515. [PMID: 36170657 DOI: 10.1146/annurev-pharmtox-052120-091058] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
In ligand bias different agonist drugs are thought to produce distinct signaling outputs when activating the same receptor. If these signaling outputs mediate therapeutic versus adverse drug effects, then agonists that selectively activate the therapeutic signaling pathway would be extremely beneficial. It has long been thought that μ-opioid receptor agonists that selectively activate G protein- over β-arrestin-dependent signaling pathways would produce effective analgesia without the adverse effects such as respiratory depression. However, more recent data indicate that most of the therapeutic and adverse effects of agonist-induced activation of the μ-opioid receptor are actually mediated by the G protein-dependent signaling pathway, and that a number of drugs described as G protein biased in fact may not be biased, but instead may be low-intrinsic-efficacy agonists. In this review we discuss the current state of the field of bias at the μ-opioid receptor and other opioid receptor subtypes.
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Affiliation(s)
- Eamonn Kelly
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, United Kingdom;
| | - Alexandra Conibear
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, United Kingdom;
| | - Graeme Henderson
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, United Kingdom;
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5
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Shiraki A, Shimizu S. The molecular associations in clathrin-coated pit regulate β-arrestin-mediated MAPK signaling downstream of μ-opioid receptor. Biochem Biophys Res Commun 2023; 640:64-72. [PMID: 36502633 DOI: 10.1016/j.bbrc.2022.11.098] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 11/25/2022] [Accepted: 11/29/2022] [Indexed: 12/03/2022]
Abstract
It has been thought that μ-opioid receptors (MOPs) activate the G protein-mediated analgesic pathway and β-arrestin 2-mediated side effect pathway; however, ligands that only minimally recruit β-arrestin 2 to MOPs may also cause opioid side effects. Moreover, such side effects have been induced in mutant mice lacking β-arrestin 2 or expressing phosphorylation-deficient MOPs that do not recruit β-arrestin 2. These findings raise the critical question of whether β-arrestin 2 recruitment to MOP triggers side effects. Here, we show that β-arrestin 1 and 2 are essential in the efficient activation of the Gi/o-mediated MAPK signaling at MOP. Moreover, the magnitude of β-arrestin-mediated signals is not correlated with the magnitude of phosphorylation of the carboxyl-terminal of MOP, which is used to evaluate the β-arrestin bias of a ligand. Instead, the molecular association with β2-adaptin and clathrin heavy chain in the formation of clathrin-coated pits is essential for β-arrestin to activate MAPK signaling. Our findings provide insights into G protein-coupled receptor-mediated signaling and further highlight a concept that the accumulation of molecules required for endocytosis is critical for activating intracellular signaling.
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Affiliation(s)
- Atsuko Shiraki
- Department of Anesthesia, Kyoto University Hospital, Kyoto City, Japan
| | - Satoshi Shimizu
- Department of Anesthesia, Kyoto University Hospital, Kyoto City, Japan.
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6
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Gamble MC, Williams BR, Singh N, Posa L, Freyberg Z, Logan RW, Puig S. Mu-opioid receptor and receptor tyrosine kinase crosstalk: Implications in mechanisms of opioid tolerance, reduced analgesia to neuropathic pain, dependence, and reward. Front Syst Neurosci 2022; 16:1059089. [PMID: 36532632 PMCID: PMC9751598 DOI: 10.3389/fnsys.2022.1059089] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 10/31/2022] [Indexed: 07/30/2023] Open
Abstract
Despite the prevalence of opioid misuse, opioids remain the frontline treatment regimen for severe pain. However, opioid safety is hampered by side-effects such as analgesic tolerance, reduced analgesia to neuropathic pain, physical dependence, or reward. These side effects promote development of opioid use disorders and ultimately cause overdose deaths due to opioid-induced respiratory depression. The intertwined nature of signaling via μ-opioid receptors (MOR), the primary target of prescription opioids, with signaling pathways responsible for opioid side-effects presents important challenges. Therefore, a critical objective is to uncouple cellular and molecular mechanisms that selectively modulate analgesia from those that mediate side-effects. One such mechanism could be the transactivation of receptor tyrosine kinases (RTKs) via MOR. Notably, MOR-mediated side-effects can be uncoupled from analgesia signaling via targeting RTK family receptors, highlighting physiological relevance of MOR-RTKs crosstalk. This review focuses on the current state of knowledge surrounding the basic pharmacology of RTKs and bidirectional regulation of MOR signaling, as well as how MOR-RTK signaling may modulate undesirable effects of chronic opioid use, including opioid analgesic tolerance, reduced analgesia to neuropathic pain, physical dependence, and reward. Further research is needed to better understand RTK-MOR transactivation signaling pathways, and to determine if RTKs are a plausible therapeutic target for mitigating opioid side effects.
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Affiliation(s)
- Mackenzie C. Gamble
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, United States
- Molecular and Translational Medicine, Department of Medicine, Boston University School of Medicine, Boston, MA, United States
| | - Benjamin R. Williams
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, United States
| | - Navsharan Singh
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, United States
| | - Luca Posa
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, United States
| | - Zachary Freyberg
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Ryan W. Logan
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, United States
- Center for Systems Neuroscience, Boston University, Boston, MA, United States
| | - Stephanie Puig
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, United States
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7
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Bilel S, Azevedo Neto J, Arfè R, Tirri M, Gaudio RM, Fantinati A, Bernardi T, Boccuto F, Marchetti B, Corli G, Serpelloni G, De-Giorgio F, Malfacini D, Trapella C, Calo' G, Marti M. In vitro and in vivo pharmaco-dynamic study of the novel fentanyl derivatives: Acrylfentanyl, Ocfentanyl and Furanylfentanyl. Neuropharmacology 2022; 209:109020. [PMID: 35247453 DOI: 10.1016/j.neuropharm.2022.109020] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 02/16/2022] [Accepted: 02/24/2022] [Indexed: 01/21/2023]
Abstract
Fentanyl derivatives (FENS) belongs to the class of Novel Synthetic Opioids that emerged in the illegal drug market of New Psychoactive Substances (NPS). These substances have been implicated in many cases of intoxication and death with overdose worldwide. Therefore, the aim of this study is to investigate the pharmaco-dynamic profiles of three fentanyl (FENT) analogues: Acrylfentanyl (ACRYLF), Ocfentanyl (OCF) and Furanylfentanyl (FUF). In vitro, we measured FENS opioid receptor efficacy, potency, and selectivity in calcium mobilization studies performed in cells coexpressing opioid receptors and chimeric G proteins and their capability to promote the interaction of the mu receptor with G protein and β-arrestin 2 in bioluminescence resonance energy transfer (BRET) studies. In vivo, we investigated the acute effects of the systemic administration of ACRYLF, OCF and FUF (0.01-15 mg/kg i.p.) on mechanical and thermal analgesia, motor impairment, grip strength and cardiorespiratory changes in CD-1 male mice. Opioid receptor specificity was investigated in vivo using naloxone (NLX; 6 mg/kg i.p) pre-treatment. In vitro, the three FENS were able to activate the mu opioid receptor in a concentration dependent manner with following rank order potency: FUF > FENT=OCF > ACRYLF. All compounds were able to elicit maximal effects similar to that of dermorphin, with the exception of FUF which displayed lower maximal effects thus behaving as a partial agonist. In the BRET G-protein assay, all compounds behaved as partial agonists for the β-arrestin 2 pathway in comparison with dermorphin, whereas FUF did not promote β-arrestin 2 recruitment, behaving as an antagonist. In vivo, all the compounds increased mechanical and thermal analgesia with following rank order potency ACRYLF = FENT > FUF > OCF and impaired motor and cardiorespiratory parameters. Among the substances tested, FUF showed lower potency for cardiorespiratory and motor effects. These findings reveal the risks associated with the use of FENS and the importance of studying the pharmaco-dynamic properties of these drugs to better understand possible therapeutic interventions in the case of toxicity.
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Affiliation(s)
- Sabrine Bilel
- Department of Translational Medicine, Section of Legal Medicine and LTTA Centre, University of Ferrara, Italy
| | - Joaquim Azevedo Neto
- Department of Neuroscience and Rehabilitation, Section of Pharmacology, University of Ferrara, Via Fossato di Mortara 17/19, 44121, Ferrara, Italy
| | - Raffaella Arfè
- Department of Translational Medicine, Section of Legal Medicine and LTTA Centre, University of Ferrara, Italy
| | - Micaela Tirri
- Department of Translational Medicine, Section of Legal Medicine and LTTA Centre, University of Ferrara, Italy
| | - Rosa Maria Gaudio
- Department of Translational Medicine, Section of Legal Medicine and LTTA Centre, University of Ferrara, Italy; Center of Gender Medicine, University of Ferrara, Italy
| | - Anna Fantinati
- Department of Chemistry and Pharmaceutical Sciences, University of Ferrara, Italy
| | - Tatiana Bernardi
- Department of Chemistry and Pharmaceutical Sciences, University of Ferrara, Italy
| | - Federica Boccuto
- Department of Chemistry and Pharmaceutical Sciences, University of Ferrara, Italy
| | - Beatrice Marchetti
- Department of Translational Medicine, Section of Legal Medicine and LTTA Centre, University of Ferrara, Italy
| | - Giorgia Corli
- Department of Translational Medicine, Section of Legal Medicine and LTTA Centre, University of Ferrara, Italy
| | - Giovanni Serpelloni
- Neuroscience Clinical Center & TMS Unit Verona, Italy and Department of Psychiatry in the College of Medicine, Drug Policy Institute, University of Florida, Gainesville, FL, United States
| | - Fabio De-Giorgio
- Institute of Public Health, Section of Legal Medicine, Università Cattolica Del Sacro Cuore, Roma, Italy; Fondazione Policlinico Universitario A. Gemelli IRCCS, Roma, Italy
| | - Davide Malfacini
- Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Italy
| | - Claudio Trapella
- Department of Chemistry and Pharmaceutical Sciences, University of Ferrara, Italy
| | - Girolamo Calo'
- Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Italy
| | - Matteo Marti
- Department of Translational Medicine, Section of Legal Medicine and LTTA Centre, University of Ferrara, Italy; Center of Gender Medicine, University of Ferrara, Italy; Collaborative Center of the National Early Warning System, Department for Anti-Drug Policies, Presidency of the Council of Ministers, Italy.
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8
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Markova V, Hejnova L, Benda A, Novotny J, Melkes B. β-Arrestin 1 and 2 similarly influence μ-opioid receptor mobility and distinctly modulate adenylyl cyclase activity. Cell Signal 2021; 87:110124. [PMID: 34450275 DOI: 10.1016/j.cellsig.2021.110124] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 08/20/2021] [Accepted: 08/22/2021] [Indexed: 01/14/2023]
Abstract
β-Arrestins are known to play a crucial role in GPCR-mediated transmembrane signaling processes. However, there are still many unanswered questions, especially those concerning the presumed similarities and differences of β-arrestin isoforms. Here, we examined the roles of β-arrestin 1 and β-arrestin 2 at different levels of μ-opioid receptor (MOR)-regulated signaling, including MOR mobility, internalization of MORs, and adenylyl cyclase (AC) activity. For this purpose, naïve HEK293 cells or HEK293 cells stably expressing YFP-tagged MOR were transfected with appropriate siRNAs to block in a specific way the expression of β-arrestin 1 or β-arrestin 2. We did not find any significant differences in the ability of β-arrestin isoforms to influence the lateral mobility of MORs in the plasma membrane. Using FRAP and line-scan FCS, we observed that knockdown of both β-arrestins similarly increased MOR lateral mobility and diminished the ability of DAMGO and endomorphin-2, respectively, to enhance and slow down receptor diffusion kinetics. However, β-arrestin 1 and β-arrestin 2 diversely affected the process of agonist-induced MOR endocytosis and exhibited distinct modulatory effects on AC function. Knockdown of β-arrestin 1, in contrast to β-arrestin 2, more effectively suppressed forskolin-stimulated AC activity and prevented the ability of activated-MORs to inhibit the enzyme activity. Moreover, we have demonstrated for the first time that β-arrestin 1, and partially β-arrestin 2, may somehow interact with AC and that this interaction is strongly supported by the enzyme activation. These data provide new insights into the functioning of β-arrestin isoforms and their distinct roles in GPCR-mediated signaling.
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Affiliation(s)
- Vendula Markova
- Department of Physiology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Lucie Hejnova
- Department of Physiology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Ales Benda
- IMCF at Biocev, Faculty of Science, Charles University, Prague, Czech Republic
| | - Jiri Novotny
- Department of Physiology, Faculty of Science, Charles University, Prague, Czech Republic.
| | - Barbora Melkes
- Department of Physiology, Faculty of Science, Charles University, Prague, Czech Republic
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9
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Watanabe C, Komiyama A, Yoshizumi M, Sakurada S, Mizoguchi H. Morphine Antinociception Restored by Use of Methadone in the Morphine-Resistant Inflammatory Pain State. Front Pharmacol 2020; 11:593647. [PMID: 33343363 PMCID: PMC7746881 DOI: 10.3389/fphar.2020.593647] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 10/23/2020] [Indexed: 01/06/2023] Open
Abstract
The antinociceptive effect of methadone in the morphine-resistant inflammatory pain state was described in the paw-withdrawal test using the complete Freund’s adjuvant (CFA)-induced mouse inflammatory pain model. After intraplantar (i.pl.) injection of CFA, thermal hyperalgesia was observed in the ipsilateral paw. The antinociceptive effects of subcutaneous (s.c.) injection of morphine, fentanyl, and oxycodone against thermal hyperalgesia in the inflammatory pain state were reduced in the ipsilateral paw 7 days after CFA pretreatment. On the contrary, the antinociceptive effect of s.c. injection of methadone was maintained in the ipsilateral paw 7 days after CFA pretreatment. The suppressed morphine antinociception in the CFA model mice was bilaterally restored following s.c. treatment with methadone 20 min prior to or 3 days after CFA pretreatment. The suppressed morphine antinociception was also bilaterally restored by intraperitoneal treatment with MK-801 30 min prior to CFA pretreatment; however, the s.c. injection of morphine 30 min prior to CFA pretreatment failed to restore the suppressed morphine antinociception in the CFA model mice. The expression level of mRNA for µ-opioid receptors 7 days after i.pl. pretreatment was not significantly changed by i.pl. pretreatment with CFA or s.c. pretreatment with methadone. In conclusion, methadone is extremely effective against thermal hyperalgesia in the morphine-resistant inflammatory pain state, and restores suppressed morphine antinociception in the inflammatory pain state without altering the expression level of mRNA for µ-opioid receptors.
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Affiliation(s)
- Chizuko Watanabe
- Department of Physiology and Anatomy, Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Asami Komiyama
- Department of Physiology and Anatomy, Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Masaru Yoshizumi
- Department of Physiology and Anatomy, Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Shinobu Sakurada
- Department of Physiology and Anatomy, Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Hirokazu Mizoguchi
- Department of Physiology and Anatomy, Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University, Sendai, Japan
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10
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Gillis A, Kliewer A, Kelly E, Henderson G, Christie MJ, Schulz S, Canals M. Critical Assessment of G Protein-Biased Agonism at the μ-Opioid Receptor. Trends Pharmacol Sci 2020; 41:947-959. [PMID: 33097283 DOI: 10.1016/j.tips.2020.09.009] [Citation(s) in RCA: 87] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 09/24/2020] [Accepted: 09/25/2020] [Indexed: 01/14/2023]
Abstract
G protein-biased agonists of the μ-opioid receptor (MOPr) have been proposed as an improved class of opioid analgesics. Recent studies have been unable to reproduce the original experiments in the β-arrestin2-knockout mouse that led to this proposal, and alternative genetic models do not support the G protein-biased MOPr agonist hypothesis. Furthermore, assessment of putatively biased ligands has been confounded by several factors, including assay amplification. As such, the extent to which current lead compounds represent mechanistically novel, extremely G protein-biased agonists is in question, as is the underlying assumption that β-arrestin2 mediates deleterious opioid effects. Addressing these current challenges represents a pressing issue to successfully advance drug development at this receptor and improve upon current opioid analgesics.
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Affiliation(s)
- Alexander Gillis
- Discipline of Pharmacology, School of Medical Sciences, University of Sydney, Sydney, NSW, Australia
| | - Andrea Kliewer
- Institute of Pharmacology and Toxicology, Jena University Hospital, Friedrich-Schiller-University, Jena, Germany
| | - Eamonn Kelly
- School of Physiology, Pharmacology, and Neuroscience, University of Bristol, Bristol, UK
| | - Graeme Henderson
- School of Physiology, Pharmacology, and Neuroscience, University of Bristol, Bristol, UK
| | - Macdonald J Christie
- Discipline of Pharmacology, School of Medical Sciences, University of Sydney, Sydney, NSW, Australia.
| | - Stefan Schulz
- Institute of Pharmacology and Toxicology, Jena University Hospital, Friedrich-Schiller-University, Jena, Germany.
| | - Meritxell Canals
- Division of Physiology, Pharmacology, and Neuroscience, School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham, UK; Centre of Membrane Proteins and Receptors, Universities of Birmingham and Nottingham, The Midlands, UK.
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11
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Lopresti NM, Esguerra M, Mermelstein PG. Sex Differences in Animal Models of Opioid Reward. CURRENT SEXUAL HEALTH REPORTS 2020; 12:186-194. [PMID: 33574737 PMCID: PMC7872138 DOI: 10.1007/s11930-020-00266-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
PURPOSE OF REVIEW This review aims to discuss sex differences observed in preclinical rodent models of opioid reward. RECENT FINDINGS Utilizing a variety of methodological approaches and drug regimens, no clear consensus has emerged regarding the effects of opiates between males and females. This is quite dissimilar to work examining psychostimulants, where female animals reliably exhibit stronger behavioral responses. SUMMARY With opioid research quickly expanding to determine the neural underpinnings of opioid addiction, further research is essential to determine the conditions wherein sex differences may occur and how they may relate to the human condition.
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Affiliation(s)
| | - Manuel Esguerra
- University of Minnesota, Twin Cities, Department of Neuroscience
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12
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Grim TW, Acevedo-Canabal A, Bohn LM. Toward Directing Opioid Receptor Signaling to Refine Opioid Therapeutics. Biol Psychiatry 2020; 87:15-21. [PMID: 31806082 PMCID: PMC6919561 DOI: 10.1016/j.biopsych.2019.10.020] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 10/23/2019] [Accepted: 10/24/2019] [Indexed: 12/22/2022]
Abstract
The mu opioid receptor (MOR) is a diversely regulated target for the alleviation of pain in the clinical setting. However, untoward side effects such as tolerance, dependence, respiratory suppression, constipation, and abuse liability detract from the general activation of these receptors. Studies in genetically modified rodent models suggest that activating G protein signaling pathways while avoiding phosphorylation of the receptor or recruitment of β-arrestin scaffolding proteins could preserve the analgesic properties of MOR agonists while avoiding certain side effects. With the development of novel MOR "biased" agonists, which lead to preferential activation of G protein pathways over receptor phosphorylation, internalization, or interaction with other effectors, this hypothesis can be tested in a native, physiological setting. Overall, it is clear that the MOR is not a simple on-off switch and that the diverse means by which the receptor can be regulated may present an opportunity to refine therapeutics for the treatment of pain.
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Affiliation(s)
- Travis W Grim
- Departments of Molecular Medicine and Neuroscience, the Scripps Research Institute, Jupiter, Florida
| | - Agnes Acevedo-Canabal
- Departments of Molecular Medicine and Neuroscience, the Scripps Research Institute, Jupiter, Florida
| | - Laura M Bohn
- Departments of Molecular Medicine and Neuroscience, the Scripps Research Institute, Jupiter, Florida.
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Viscusi ER. Improving the therapeutic window of conventional opioids: novel differential signaling modulators. Reg Anesth Pain Med 2019; 44:32-37. [PMID: 30640650 DOI: 10.1136/rapm-2018-000010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 05/04/2018] [Accepted: 05/23/2018] [Indexed: 02/02/2023]
Abstract
Conventional opioids are widely used for acute pain management in the postoperative setting. However, a primary concern with conventional opioids is their therapeutic window-the range between doses that produce the desired therapeutic effect (analgesia) and doses that produce unwanted opioid-related adverse events (ORAEs). Conventional µ receptor opioids have a narrow therapeutic window in part because of their mechanism of action (MoA): they bind to µ receptors and non-selectively activate two intracellular signaling pathways, leading to analgesia and to ORAEs. This review explores the clinical potential of µ receptor ligands with differential signaling. Agents with a 'differential signaling" MoA represent an innovative approach that may enhance the therapeutic window. These agents modulate µ receptor activity to selectively engage downstream signaling pathways associated with analgesia while limiting activity in downstream signaling pathways that lead to ORAEs. Differential signaling may fulfill an unmet need in the management of postoperative pain.
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Affiliation(s)
- Eugene R Viscusi
- Department of Anesthesiology, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA 19107, USA
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15
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Caputi FF, Rullo L, Stamatakos S, Candeletti S, Romualdi P. Interplay between the Endogenous Opioid System and Proteasome Complex: Beyond Signaling. Int J Mol Sci 2019; 20:ijms20061441. [PMID: 30901925 PMCID: PMC6470665 DOI: 10.3390/ijms20061441] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 03/13/2019] [Accepted: 03/19/2019] [Indexed: 02/07/2023] Open
Abstract
Intracellular signaling mechanisms underlying the opioid system regulation of nociception, neurotransmitters release, stress responses, depression, and the modulation of reward circuitry have been investigated from different points of view. The presence of the ubiquitin proteasome system (UPS) in the synaptic terminations suggest a potential role of ubiquitin-dependent mechanisms in the control of the membrane occupancy by G protein-coupled receptors (GPCRs), including those belonging to the opioid family. In this review, we focused our attention on the role played by the ubiquitination processes and by UPS in the modulation of opioid receptor signaling and in pathological conditions involving the endogenous opioid system. The collective evidence here reported highlights the potential usefulness of proteasome inhibitors in neuropathic pain, addictive behavior, and analgesia since these molecules can reduce pain behavioral signs, heroin self-administration, and the development of morphine analgesic tolerance. Moreover, the complex mechanisms involved in the effects induced by opioid agonists binding to their receptors include the ubiquitination process as a post-translational modification which plays a relevant role in receptor trafficking and degradation. Hence, UPS modulation may offer novel opportunities to control the balance between therapeutic versus adverse effects evoked by opioid receptor activation, thus, representing a promising druggable target.
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Affiliation(s)
- Francesca Felicia Caputi
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna, Irnerio 48, 40126 Bologna, Italy.
| | - Laura Rullo
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna, Irnerio 48, 40126 Bologna, Italy.
| | - Serena Stamatakos
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna, Irnerio 48, 40126 Bologna, Italy.
| | - Sanzio Candeletti
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna, Irnerio 48, 40126 Bologna, Italy.
| | - Patrizia Romualdi
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna, Irnerio 48, 40126 Bologna, Italy.
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16
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Deng M, Chen SR, Chen H, Luo Y, Dong Y, Pan HL. Mitogen-activated protein kinase signaling mediates opioid-induced presynaptic NMDA receptor activation and analgesic tolerance. J Neurochem 2018; 148:275-290. [PMID: 30444263 DOI: 10.1111/jnc.14628] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 11/01/2018] [Accepted: 11/09/2018] [Indexed: 12/15/2022]
Abstract
Opioid-induced hyperalgesia and analgesic tolerance can lead to dose escalation and inadequate pain treatment with μ-opioid receptor agonists. Opioids cause tonic activation of glutamate NMDA receptors (NMDARs) at primary afferent terminals, increasing nociceptive input. However, the signaling mechanisms responsible for opioid-induced activation of pre-synaptic NMDARs in the spinal dorsal horn remain unclear. In this study, we determined the role of MAPK signaling in opioid-induced pre-synaptic NMDAR activation caused by chronic morphine administration. Whole-cell recordings of excitatory post-synaptic currents (EPSCs) were performed on dorsal horn neurons in rat spinal cord slices. Chronic morphine administration markedly increased the frequency of miniature EPSCs, increased the amplitude of monosynaptic EPSCs evoked from the dorsal root, and reduced the paired-pulse ratio of evoked EPSCs. These changes were fully reversed by an NMDAR antagonist and normalized by inhibiting extracellular signal-regulated kinase 1/2 (ERK1/2), p38, or c-Jun N-terminal kinase (JNK). Furthermore, intrathecal injection of a selective ERK1/2, p38, or JNK inhibitor blocked pain hypersensitivity induced by chronic morphine treatment. These inhibitors also similarly attenuated a reduction in morphine's analgesic effect in rats. In addition, co-immunoprecipitation assays revealed that NMDARs formed a protein complex with ERK1/2, p38, and JNK in the spinal cord and that chronic morphine treatment increased physical interactions of NMDARs with these three MAPKs. Our findings suggest that opioid-induced hyperalgesia and analgesic tolerance are mediated by tonic activation of pre-synaptic NMDARs via three functionally interrelated MAPKs at the spinal cord level. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* because it provided all relevant information to reproduce the study in the manuscript. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/.
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Affiliation(s)
- Meichun Deng
- Center for Neuroscience and Pain Research, Department of Anesthesiology and Perioperative Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.,Department of Biochemistry and Molecular Biology, School of Life Sciences, Central South University, Changsha, Hunan, China
| | - Shao-Rui Chen
- Center for Neuroscience and Pain Research, Department of Anesthesiology and Perioperative Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Hong Chen
- Center for Neuroscience and Pain Research, Department of Anesthesiology and Perioperative Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Yi Luo
- Center for Neuroscience and Pain Research, Department of Anesthesiology and Perioperative Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.,Department of Clinical Laboratory Medicine, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, China
| | - Yingchun Dong
- Center for Neuroscience and Pain Research, Department of Anesthesiology and Perioperative Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.,Department of Anesthesiology, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Hui-Lin Pan
- Center for Neuroscience and Pain Research, Department of Anesthesiology and Perioperative Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
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17
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Araldi D, Ferrari LF, Levine JD. Mu-opioid Receptor (MOR) Biased Agonists Induce Biphasic Dose-dependent Hyperalgesia and Analgesia, and Hyperalgesic Priming in the Rat. Neuroscience 2018; 394:60-71. [PMID: 30342200 DOI: 10.1016/j.neuroscience.2018.10.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 09/17/2018] [Accepted: 10/09/2018] [Indexed: 01/19/2023]
Abstract
Stimulation of the mu-opioid receptor (MOR) on nociceptors with fentanyl can produce hyperalgesia (opioid-induced hyperalgesia, OIH) and hyperalgesic priming, a model of transition to chronic pain. We investigated if local and systemic administration of biased MOR agonists (PZM21 and TRV130 [oliceridine]), which preferentially activate G-protein over β-arrestin translocation, and have been reported to minimize some opioid side effects, also produces OIH and priming. Injected intradermally (100 ng), both biased agonists induced mechanical hyperalgesia and, when injected at the same site, 5 days later, prostaglandin E2 (PGE2) produced prolonged hyperalgesia (priming). OIH and priming were both prevented by intrathecal treatment with an oligodeoxynucleotide (ODN) antisense (AS) for MOR mRNA. Agents that reverse Type I (the protein translation inhibitor cordycepin) and Type II (combination of Src and mitogen-activated protein kinase [MAPK] inhibitors) priming, or their combination, did not reverse priming induced by local administration of PZM21 or TRV130. While systemic PZM21 at higher doses (1 and 10 mg/kg) induced analgesia, lower doses (0.001, 0.01, 0.1, and 0.3 mg/kg) induced hyperalgesia; all doses induced priming. Hyperalgesia, analgesia and priming induced by systemic administration of PZM21 were also prevented by MOR AS-ODN. And, priming induced by systemic PZM21 was also not reversed by intradermal cordycepin or the combination of Src and MAPK inhibitors. Thus, maintenance of priming induced by biased MOR agonists, in the peripheral terminal of nociceptors, has a novel mechanism.
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Affiliation(s)
- Dionéia Araldi
- Departments of Medicine and Oral Surgery, and Division of Neuroscience, University of California at San Francisco, 513 Parnassus Avenue, San Francisco, CA 94143, USA.
| | - Luiz F Ferrari
- Departments of Medicine and Oral Surgery, and Division of Neuroscience, University of California at San Francisco, 513 Parnassus Avenue, San Francisco, CA 94143, USA.
| | - Jon D Levine
- Departments of Medicine and Oral Surgery, and Division of Neuroscience, University of California at San Francisco, 513 Parnassus Avenue, San Francisco, CA 94143, USA.
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18
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Devereaux AL, Mercer SL, Cunningham CW. DARK Classics in Chemical Neuroscience: Morphine. ACS Chem Neurosci 2018; 9:2395-2407. [PMID: 29757600 DOI: 10.1021/acschemneuro.8b00150] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
As the major psychoactive agent in opium and direct precursor for heroin, morphine is a historically critical molecule in chemical neuroscience. A structurally complex phenanthrene alkaloid produced by Papaver somniferum, morphine has fascinated chemists seeking to disentangle pharmacologically beneficial analgesic effects from addiction, tolerance, and dependence liabilities. In this review, we will detail the history of morphine, from the first extraction and isolation by Sertürner in 1804 to the illicit use of morphine and proliferation of opioid use and abuse disorders currently ravaging the United States. Morphine is a molecule of great cultural relevance, as the agent that single-handedly transformed our understanding of pharmacognosy, receptor dynamics, and substance abuse and dependence disorders.
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Affiliation(s)
- Andrea L. Devereaux
- Department of Pharmaceutical Sciences, School of Pharmacy, Concordia University Wisconsin, Mequon, Wisconsin 53097, United States
| | - Susan L. Mercer
- Department of Pharmaceutical Sciences, College of Pharmacy, Lipscomb University, Nashville, Tennessee 37204, United States
| | - Christopher W. Cunningham
- Department of Pharmaceutical Sciences, School of Pharmacy, Concordia University Wisconsin, Mequon, Wisconsin 53097, United States
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19
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Cannaert A, Vasudevan L, Friscia M, Mohr ALA, Wille SMR, Stove CP. Activity-Based Concept to Screen Biological Matrices for Opiates and (Synthetic) Opioids. Clin Chem 2018; 64:1221-1229. [DOI: 10.1373/clinchem.2018.289496] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 05/04/2018] [Indexed: 11/06/2022]
Abstract
Abstract
BACKGROUND
Detection of new highly potent synthetic opioids is challenging as new compounds enter the market. Here we present a novel screening method for the detection of opiates and (synthetic) opioids based on their activity.
METHODS
A cell-based system was set up in which activation of the μ-opioid receptor (MOR) led to recruitment of β-arrestin 2, resulting in functional complementation of a split NanoLuc luciferase and allowing readout via bioluminescence. Assay performance was evaluated on 107 postmortem blood samples. Blood (500 μL) was extracted via solid-phase extraction. Following evaporation and reconstitution in 100 μL of Opti-MEM® I, 20 μL was analyzed in the bioassay.
RESULTS
In 8 samples containing synthetic opioids, in which no positive signal was obtained in the bioassay, quadrupole time-of-flight mass spectrometry revealed the MOR antagonist naloxone, which can prevent receptor activation. Hence, further evaluation did not include these samples. For U-47700 (74.5–547 ng/mL) and furanyl fentanyl (<1–38.8 ng/mL), detection was 100% (8/8) for U-47700 and 95% (21/22) for furanyl fentanyl. An analytical specificity of 93% (55/59) was obtained for the opioid negatives. From an additional 10 samples found to contain other opioids, 5 were correctly scored positive. Nondetection in 5 cases could be explained by very low concentrations (<1 ng/mL alfentanil/sufentanil) or presence of inactive enantiomers.
CONCLUSIONS
The MOR reporter assay allows rapid identification of opioid activity in blood. Although the cooccurrence of opioid antagonists is currently a limitation, the bioassay's high detection capability, specificity, and untargeted nature may render it a useful first-line screening tool to investigate potential opioid intoxications.
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Affiliation(s)
- Annelies Cannaert
- Laboratory of Toxicology, Department of Bioanalysis, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
- Laboratory of Toxicology, National Institute of Criminalistics and Criminology, Brussels, Belgium
| | - Lakshmi Vasudevan
- Laboratory of Toxicology, Department of Bioanalysis, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
| | - Melissa Friscia
- The Center for Forensic Science Research and Education, Fredric Rieders Family Foundation, Willow Grove, PA
| | - Amanda L A Mohr
- The Center for Forensic Science Research and Education, Fredric Rieders Family Foundation, Willow Grove, PA
| | - Sarah M R Wille
- Laboratory of Toxicology, National Institute of Criminalistics and Criminology, Brussels, Belgium
| | - Christophe P Stove
- Laboratory of Toxicology, Department of Bioanalysis, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
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20
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Dietis N, Niwa H, Tose R, McDonald J, Ruggieri V, Filaferro M, Vitale G, Micheli L, Ghelardini C, Salvadori S, Calo G, Guerrini R, Rowbotham DJ, Lambert DG. In vitro and in vivo characterization of the bifunctional μ and δ opioid receptor ligand UFP-505. Br J Pharmacol 2018; 175:2881-2896. [PMID: 29524334 PMCID: PMC6016625 DOI: 10.1111/bph.14199] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 02/21/2018] [Accepted: 02/22/2018] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Targeting more than one opioid receptor type simultaneously may have analgesic advantages in reducing side-effects. We have evaluated the mixed μ opioid receptor agonist/ δ opioid receptor antagonist UFP-505 in vitro and in vivo. EXPERIMENTAL APPROACH We measured receptor density and function in single μ, δ and μ /δ receptor double expression systems. GTPγ35 S binding, cAMP formation and arrestin recruitment were measured. Antinociceptive activity was measured in vivo using tail withdrawal and paw pressure tests following acute and chronic treatment. In some experiments, we collected tissues to measure receptor densities. KEY RESULTS UFP-505 bound to μ receptors with full agonist activity and to δ receptors as a low efficacy partial agonist At μ, but not δ receptors, UFP-505 binding recruited arrestin. Unlike morphine, UFP-505 treatment internalized μ receptors and there was some evidence for internalization of δ receptors. Similar data were obtained in a μ /δ receptor double expression system. In rats, acute UFP-505 or morphine, injected intrathecally, was antinociceptive. In tissues harvested from these experiments, μ and δ receptor density was decreased after UFP-505 but not morphine treatment, in agreement with in vitro data. Both morphine and UFP-505 induced significant tolerance. CONCLUSIONS AND IMPLICATIONS In this study, UFP-505 behaved as a full agonist at μ receptors with variable activity at δ receptors. This bifunctional compound was antinociceptive in rats after intrathecal administration. In this model, dual targeting provided no advantages in terms of tolerance liability. LINKED ARTICLES This article is part of a themed section on Emerging Areas of Opioid Pharmacology. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.14/issuetoc.
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Affiliation(s)
- N Dietis
- Department of Cardiovascular SciencesUniversity of Leicester, Division of Anaesthesia, Critical Care and Pain Management, Leicester Royal InfirmaryLeicesterUK
| | - H Niwa
- Department of Cardiovascular SciencesUniversity of Leicester, Division of Anaesthesia, Critical Care and Pain Management, Leicester Royal InfirmaryLeicesterUK
| | - R Tose
- Department of Cardiovascular SciencesUniversity of Leicester, Division of Anaesthesia, Critical Care and Pain Management, Leicester Royal InfirmaryLeicesterUK
| | - J McDonald
- Department of Cardiovascular SciencesUniversity of Leicester, Division of Anaesthesia, Critical Care and Pain Management, Leicester Royal InfirmaryLeicesterUK
| | - V Ruggieri
- Department of Oncology Haematology and Respiratory DiseasesUniversity of Modena and Reggio EmiliaModenaItaly
| | - M Filaferro
- Department of Biomedical, Metabolic and Neuro‐SciencesUniversity of Modena and Reggio EmiliaModenaItaly
| | - G Vitale
- Section of Pharmacology, Department of Life SciencesUniversity of Modena and Reggio EmiliaModenaItaly
| | - L Micheli
- Department of Preclinical and Clinical PharmacologyUniversity of FlorenceFlorenceItaly
| | - C Ghelardini
- Department of Preclinical and Clinical PharmacologyUniversity of FlorenceFlorenceItaly
| | - S Salvadori
- Department of Experimental and Clinical Medicine, Section of PharmacologyUniversity of FerraraFerraraItaly
| | - G Calo
- Department of Experimental and Clinical Medicine, Section of PharmacologyUniversity of FerraraFerraraItaly
| | - R Guerrini
- Department of Pharmaceutical SciencesUniversity of FerraraFerraraItaly
| | - D J Rowbotham
- Department of Health SciencesUniversity of Leicester, Division of Anaesthesia, Critical Care and Pain Management, Leicester Royal InfirmaryLeicesterUK
| | - D G Lambert
- Department of Cardiovascular SciencesUniversity of Leicester, Division of Anaesthesia, Critical Care and Pain Management, Leicester Royal InfirmaryLeicesterUK
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Singla N, Minkowitz HS, Soergel DG, Burt DA, Subach RA, Salamea MY, Fossler MJ, Skobieranda F. A randomized, Phase IIb study investigating oliceridine (TRV130), a novel µ-receptor G-protein pathway selective (μ-GPS) modulator, for the management of moderate to severe acute pain following abdominoplasty. J Pain Res 2017; 10:2413-2424. [PMID: 29062240 PMCID: PMC5638571 DOI: 10.2147/jpr.s137952] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Background Oliceridine (TRV130), a novel μ-receptor G-protein pathway selective (μ-GPS) modulator, was designed to improve the therapeutic window of conventional opioids by activating G-protein signaling while causing low β-arrestin recruitment to the μ receptor. This randomized, double-blind, patient-controlled analgesia Phase IIb study was conducted to investigate the efficacy, safety, and tolerability of oliceridine compared with morphine and placebo in patients with moderate to severe pain following abdominoplasty (NCT02335294; oliceridine is an investigational agent not yet approved by the US Food and Drug Administration). Methods Patients were randomized to receive postoperative regimens of intravenous oliceridine (loading/patient-controlled demand doses [mg/mg]: 1.5/0.10 [regimen A]; 1.5/0.35 [regimen B]), morphine (4.0/1.0), or placebo with treatment initiated within 4 hours of surgery and continued as needed for 24 hours. Results Two hundred patients were treated (n=39, n=39, n=83, and n=39 in the oliceridine regimen A, oliceridine regimen B, morphine, and placebo groups, respectively). Patients were predominantly female (n=198 [99%]) and had a mean age of 38.2 years, weight of 71.2 kg, and baseline pain score of 7.7 (on 11-point numeric pain rating scale). Patients receiving the oliceridine regimens had reductions in average pain scores (model-based change in time-weighted average versus placebo over 24 hours) of 2.3 and 2.1 points, respectively (P=0.0001 and P=0.0005 versus placebo); patients receiving morphine had a similar reduction (2.1 points; P<0.0001 versus placebo). A lower prevalence of adverse events (AEs) related to nausea, vomiting, and respiratory function was observed with the oliceridine regimens than with morphine (P<0.05). Other AEs with oliceridine were generally dose-related and similar in nature to those observed with conventional opioids; no serious AEs were reported with oliceridine. Conclusion These results suggest that oliceridine may provide effective, rapid analgesia in patients with moderate to severe postoperative pain, with an acceptable safety/tolerability profile and potentially wider therapeutic window than morphine.
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22
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Gan TJ. Poorly controlled postoperative pain: prevalence, consequences, and prevention. J Pain Res 2017; 10:2287-2298. [PMID: 29026331 PMCID: PMC5626380 DOI: 10.2147/jpr.s144066] [Citation(s) in RCA: 625] [Impact Index Per Article: 89.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
This review provides an overview of the clinical issue of poorly controlled postoperative pain and therapeutic approaches that may help to address this common unresolved health-care challenge. Postoperative pain is not adequately managed in greater than 80% of patients in the US, although rates vary depending on such factors as type of surgery performed, analgesic/anesthetic intervention used, and time elapsed after surgery. Poorly controlled acute postoperative pain is associated with increased morbidity, functional and quality-of-life impairment, delayed recovery time, prolonged duration of opioid use, and higher health-care costs. In addition, the presence and intensity of acute pain during or after surgery is predictive of the development of chronic pain. More effective analgesic/anesthetic measures in the perioperative period are needed to prevent the progression to persistent pain. Although clinical findings are inconsistent, some studies of local anesthetics and nonopioid analgesics have suggested potential benefits as preventive interventions. Conventional opioids remain the standard of care for the management of acute postoperative pain; however, the risk of opioid-related adverse events can limit optimal dosing for analgesia, leading to poorly controlled acute postoperative pain. Several new opioids have been developed that modulate μ-receptor activity by selectively engaging intracellular pathways associated with analgesia and not those associated with adverse events, creating a wider therapeutic window than unselective conventional opioids. In clinical studies, oliceridine (TRV130), a novel μ-receptor G-protein pathway-selective modulator, produced rapid postoperative analgesia with reduced prevalence of adverse events versus morphine.
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Affiliation(s)
- Tong J Gan
- Stony Brook University, Stony Brook, NY, USA
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23
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Porter-Stransky KA, Weinshenker D. Arresting the Development of Addiction: The Role of β-Arrestin 2 in Drug Abuse. J Pharmacol Exp Ther 2017; 361:341-348. [PMID: 28302862 DOI: 10.1124/jpet.117.240622] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 03/15/2017] [Indexed: 01/01/2023] Open
Abstract
The protein β-arrestin (βarr) 2 directly interacts with receptors and signaling pathways that mediate the behavioral effects of drugs of abuse, making it a prime candidate for therapeutic interventions. βarr2 drives desensitization and internalization of G protein-coupled receptors, including dopamine, opioid, and cannabinoid receptors, and it can also trigger G protein-independent intracellular signaling. βarr2 mediates several drug-induced behaviors, but the relationship is complex and dependent on the type of behavior (e.g., psychomotor versus reward), the class of drug (e.g., psychostimulant versus opioid), and the circuit being interrogated (e.g., brain region, cell type, and specific receptor ligand). Here we discuss the current state of research concerning the contribution of βarr2 to the psychomotor and rewarding effects of addictive drugs. Next we identify key knowledge gaps and suggest new tools and approaches needed to further elucidate the neuroanatomical substrates and neurobiological mechanisms to explain how βarr2 modulates behavioral responses to drugs of abuse, as well as its potential as a therapeutic target.
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Affiliation(s)
| | - David Weinshenker
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia
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24
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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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25
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Gundry J, Glenn R, Alagesan P, Rajagopal S. A Practical Guide to Approaching Biased Agonism at G Protein Coupled Receptors. Front Neurosci 2017; 11:17. [PMID: 28174517 PMCID: PMC5258729 DOI: 10.3389/fnins.2017.00017] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2016] [Accepted: 01/09/2017] [Indexed: 01/11/2023] Open
Abstract
Biased agonism, the ability of a receptor to differentially activate downstream signaling pathways depending on binding of a "biased" agonist compared to a "balanced" agonist, is a well-established paradigm for G protein-coupled receptor (GPCR) signaling. Biased agonists have the promise to act as smarter drugs by specifically targeting pathogenic or therapeutic signaling pathways while avoiding others that could lead to side effects. A number of biased agonists targeting a wide array of GPCRs have been described, primarily based on their signaling in pharmacological assays. However, with the promise of biased agonists as novel therapeutics, comes the peril of not fully characterizing and understanding the activities of these compounds. Indeed, it is likely that some of the compounds that have been described as biased, may not be if quantitative approaches for bias assessment are used. Moreover, cell specific effects can result in "system bias" that cannot be accounted by current approaches for quantifying ligand bias. Other confounding includes kinetic effects which can alter apparent bias and differential propagation of biological signal that results in different levels of amplification of reporters downstream of the same effector. Moreover, the effects of biased agonists frequently cannot be predicted from their pharmacological profiles, and must be tested in the vivo physiological context. Thus, the development of biased agonists as drugs requires a detailed pharmacological characterization, involving both qualitative and quantitative approaches, and a detailed physiological characterization. With this understanding, we stand on the edge of a new era of smarter drugs that target GPCRs.
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Affiliation(s)
- Jaimee Gundry
- Trinity College of Arts and Sciences, Duke University Durham, NC, USA
| | - Rachel Glenn
- Trinity College of Arts and Sciences, Duke University Durham, NC, USA
| | - Priya Alagesan
- Trinity College of Arts and Sciences, Duke University Durham, NC, USA
| | - Sudarshan Rajagopal
- Department of Medicine and Biochemistry, Duke University Medical Center Durham, NC, USA
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Siuda ER, Carr R, Rominger DH, Violin JD. Biased mu-opioid receptor ligands: a promising new generation of pain therapeutics. Curr Opin Pharmacol 2016; 32:77-84. [PMID: 27936408 DOI: 10.1016/j.coph.2016.11.007] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 11/15/2016] [Accepted: 11/18/2016] [Indexed: 01/14/2023]
Abstract
Opioid chemistry and biology occupy a pivotal place in the history of pharmacology and medicine. Morphine offers unmatched efficacy in alleviating acute pain, but is also associated with a host of adverse side effects. The advent of biased agonism at G protein-coupled receptors has expanded our understanding of intracellular signaling and highlighted the concept that certain ligands are able to differentially modulate downstream pathways. The ability to target one pathway over another has allowed for the development of biased ligands with robust clinical efficacy and fewer adverse events. In this review we summarize these concepts with an emphasis on biased mu opioid receptor pharmacology and highlight how far opioid pharmacology has evolved.
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Affiliation(s)
- Edward R Siuda
- Trevena Inc., 1018 West 8th Avenue, Suite A, King of Prussia, PA 19406, USA
| | - Richard Carr
- Trevena Inc., 1018 West 8th Avenue, Suite A, King of Prussia, PA 19406, USA
| | - David H Rominger
- Trevena Inc., 1018 West 8th Avenue, Suite A, King of Prussia, PA 19406, USA
| | - Jonathan D Violin
- Trevena Inc., 1018 West 8th Avenue, Suite A, King of Prussia, PA 19406, USA.
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Grinnell SG, Ansonoff M, Marrone GF, Lu Z, Narayan A, Xu J, Rossi G, Majumdar S, Pan YX, Bassoni DL, Pintar J, Pasternak GW. Mediation of buprenorphine analgesia by a combination of traditional and truncated mu opioid receptor splice variants. Synapse 2016; 70:395-407. [PMID: 27223691 PMCID: PMC4980214 DOI: 10.1002/syn.21914] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 04/21/2016] [Accepted: 05/22/2016] [Indexed: 01/17/2023]
Abstract
Buprenorphine has long been classified as a mu analgesic, although its high affinity for other opioid receptor classes and the orphanin FQ/nociceptin ORL1 receptor may contribute to its other actions. The current studies confirmed a mu mechanism for buprenorphine analgesia, implicating several subsets of mu receptor splice variants. Buprenorphine analgesia depended on the expression of both exon 1-associated traditional full length 7 transmembrane (7TM) and exon 11-associated truncated 6 transmembrane (6TM) MOR-1 variants. In genetic models, disruption of delta, kappa1 or ORL1 receptors had no impact on buprenorphine analgesia, while loss of the traditional 7TM MOR-1 variants in an exon 1 knockout (KO) mouse markedly lowered buprenorphine analgesia. Loss of the truncated 6TM variants in an exon 11 KO mouse totally eliminated buprenorphine analgesia. In distinction to analgesia, the inhibition of gastrointestinal transit and stimulation of locomotor activity were independent of truncated 6TM variants. Restoring expression of a 6TM variant with a lentivirus rescued buprenorphine analgesia in an exon 11 KO mouse that still expressed the 7TM variants. Despite a potent and robust stimulation of (35) S-GTPγS binding in MOR-1 expressing CHO cells, buprenorphine failed to recruit β-arrestin-2 binding at doses as high as 10 µM. Buprenorphine was an antagonist in DOR-1 expressing cells and an inverse agonist in KOR-1 cells. Buprenorphine analgesia is complex and requires multiple mu receptor splice variant classes but other actions may involve alternative receptors.
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Affiliation(s)
- Steven G Grinnell
- Department of Neurology and Molecular Pharmacology and Chemistry Program, Memorial Sloan-Kettering Cancer Center, New York, New York
- Neuroscience Program, Weill Cornell Graduate School of Medical Sciences, New York, New York
| | - Michael Ansonoff
- Department of Neuroscience and Cell Biology, UMDNJ-Robert Wood Johnson Medical School, Piscataway, New Jersey
| | - Gina F Marrone
- Department of Neurology and Molecular Pharmacology and Chemistry Program, Memorial Sloan-Kettering Cancer Center, New York, New York
- Neuroscience Program, Weill Cornell Graduate School of Medical Sciences, New York, New York
| | - Zhigang Lu
- Department of Neurology and Molecular Pharmacology and Chemistry Program, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Ankita Narayan
- Department of Neurology and Molecular Pharmacology and Chemistry Program, Memorial Sloan-Kettering Cancer Center, New York, New York
- Neuroscience Program, Weill Cornell Graduate School of Medical Sciences, New York, New York
| | - Jin Xu
- Department of Neurology and Molecular Pharmacology and Chemistry Program, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Grace Rossi
- Department of Psychology, Long Island University, Post Campus, Brookville, New York
| | - Susruta Majumdar
- Department of Neurology and Molecular Pharmacology and Chemistry Program, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Ying-Xian Pan
- Department of Neurology and Molecular Pharmacology and Chemistry Program, Memorial Sloan-Kettering Cancer Center, New York, New York
| | | | - John Pintar
- Department of Neuroscience and Cell Biology, UMDNJ-Robert Wood Johnson Medical School, Piscataway, New Jersey
| | - Gavril W Pasternak
- Department of Neurology and Molecular Pharmacology and Chemistry Program, Memorial Sloan-Kettering Cancer Center, New York, New York
- Neuroscience Program, Weill Cornell Graduate School of Medical Sciences, New York, New York
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Bhalla S, Andurkar SV, Gulati A. Neurobiology of opioid withdrawal: Role of the endothelin system. Life Sci 2016; 159:34-42. [DOI: 10.1016/j.lfs.2016.01.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 01/06/2016] [Accepted: 01/11/2016] [Indexed: 02/04/2023]
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Pačesová D, Novotný J, Bendová Z. The effect of chronic morphine or methadone exposure and withdrawal on clock gene expression in the rat suprachiasmatic nucleus and AA-NAT activity in the pineal gland. Physiol Res 2016; 65:517-25. [PMID: 27070740 DOI: 10.33549/physiolres.933183] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The circadian rhythms of many behavioral and physiological functions are regulated by the major circadian pacemaker in the suprachiasmatic nucleus. Long-term opiate addiction and drug withdrawal may affect circadian rhythmicity of various hormones or the sleep/activity pattern of many experimental subjects; however, limited research has been done on the long-term effects of sustained opiate administration on the intrinsic rhythmicity in the suprachiasmatic nucleus and pineal gland. Here we compared the effects of repeated daily treatment of rats with morphine or methadone and subsequent naloxone-precipitated withdrawal on the expression of the Per1, Per2, and Avp mRNAs in the suprachiasmatic nucleus and on arylalkylamine N-acetyltransferase activity in the pineal gland. We revealed that 10-day administration and withdrawal of both these drugs failed to affect clock genes and Avp expression in the SCN. Our results indicate that opioid-induced changes in behavioral and physiological rhythms originate in brain structures downstream of the suprachiasmatic nucleus regulatory output pathway. Furthermore, we observed that acute withdrawal from methadone markedly extended the period of high night AA-NAT activity in the pineal gland. This suggests that withdrawal from methadone, a widely used drug for the treatment of opioid dependence, may have stronger impact on melatonin synthesis than withdrawal from morphine.
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Affiliation(s)
- D Pačesová
- Department of Physiology, Faculty of Science, Charles University in Prague, Prague, Czech Republic.
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Toll L, Bruchas MR, Calo' G, Cox BM, Zaveri NT. Nociceptin/Orphanin FQ Receptor Structure, Signaling, Ligands, Functions, and Interactions with Opioid Systems. Pharmacol Rev 2016; 68:419-57. [PMID: 26956246 PMCID: PMC4813427 DOI: 10.1124/pr.114.009209] [Citation(s) in RCA: 213] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The NOP receptor (nociceptin/orphanin FQ opioid peptide receptor) is the most recently discovered member of the opioid receptor family and, together with its endogenous ligand, N/OFQ, make up the fourth members of the opioid receptor and opioid peptide family. Because of its more recent discovery, an understanding of the cellular and behavioral actions induced by NOP receptor activation are less well developed than for the other members of the opioid receptor family. All of these factors are important because NOP receptor activation has a clear modulatory role on mu opioid receptor-mediated actions and thereby affects opioid analgesia, tolerance development, and reward. In addition to opioid modulatory actions, NOP receptor activation has important effects on motor function and other physiologic processes. This review discusses how NOP pharmacology intersects, contrasts, and interacts with the mu opioid receptor in terms of tertiary structure and mechanism of receptor activation; location of receptors in the central nervous system; mechanisms of desensitization and downregulation; cellular actions; intracellular signal transduction pathways; and behavioral actions with respect to analgesia, tolerance, dependence, and reward. This is followed by a discussion of the agonists and antagonists that have most contributed to our current knowledge. Because NOP receptors are highly expressed in brain and spinal cord and NOP receptor activation sometimes synergizes with mu receptor-mediated actions and sometimes opposes them, an understanding of NOP receptor pharmacology in the context of these interactions with the opioid receptors will be crucial to the development of novel therapeutics that engage the NOP receptor.
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Affiliation(s)
- Lawrence Toll
- Torrey Pines Institute for Molecular Studies, Port St. Lucie, Florida (L.T.); Departments of Anesthesiology, and Neuroscience, Washington University School of Medicine, St. Louis, Missouri (M.R.B.); Section of Pharmacology, Department of Medical Science, and National Institute of Neurosciences, University of Ferrara, Ferrara, Italy (G.C.); Professor of Pharmacology & Neuroscience, Uniformed Services University, Bethesda, Maryland (B.M.C.); and Astraea Therapeutics, LLC, Mountain View, California (N.T.Z.)
| | - Michael R Bruchas
- Torrey Pines Institute for Molecular Studies, Port St. Lucie, Florida (L.T.); Departments of Anesthesiology, and Neuroscience, Washington University School of Medicine, St. Louis, Missouri (M.R.B.); Section of Pharmacology, Department of Medical Science, and National Institute of Neurosciences, University of Ferrara, Ferrara, Italy (G.C.); Professor of Pharmacology & Neuroscience, Uniformed Services University, Bethesda, Maryland (B.M.C.); and Astraea Therapeutics, LLC, Mountain View, California (N.T.Z.)
| | - Girolamo Calo'
- Torrey Pines Institute for Molecular Studies, Port St. Lucie, Florida (L.T.); Departments of Anesthesiology, and Neuroscience, Washington University School of Medicine, St. Louis, Missouri (M.R.B.); Section of Pharmacology, Department of Medical Science, and National Institute of Neurosciences, University of Ferrara, Ferrara, Italy (G.C.); Professor of Pharmacology & Neuroscience, Uniformed Services University, Bethesda, Maryland (B.M.C.); and Astraea Therapeutics, LLC, Mountain View, California (N.T.Z.)
| | - Brian M Cox
- Torrey Pines Institute for Molecular Studies, Port St. Lucie, Florida (L.T.); Departments of Anesthesiology, and Neuroscience, Washington University School of Medicine, St. Louis, Missouri (M.R.B.); Section of Pharmacology, Department of Medical Science, and National Institute of Neurosciences, University of Ferrara, Ferrara, Italy (G.C.); Professor of Pharmacology & Neuroscience, Uniformed Services University, Bethesda, Maryland (B.M.C.); and Astraea Therapeutics, LLC, Mountain View, California (N.T.Z.)
| | - Nurulain T Zaveri
- Torrey Pines Institute for Molecular Studies, Port St. Lucie, Florida (L.T.); Departments of Anesthesiology, and Neuroscience, Washington University School of Medicine, St. Louis, Missouri (M.R.B.); Section of Pharmacology, Department of Medical Science, and National Institute of Neurosciences, University of Ferrara, Ferrara, Italy (G.C.); Professor of Pharmacology & Neuroscience, Uniformed Services University, Bethesda, Maryland (B.M.C.); and Astraea Therapeutics, LLC, Mountain View, California (N.T.Z.)
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Rankovic Z, Brust TF, Bohn LM. Biased agonism: An emerging paradigm in GPCR drug discovery. Bioorg Med Chem Lett 2016; 26:241-250. [PMID: 26707396 PMCID: PMC5595354 DOI: 10.1016/j.bmcl.2015.12.024] [Citation(s) in RCA: 194] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 12/04/2015] [Accepted: 12/08/2015] [Indexed: 01/11/2023]
Abstract
G protein coupled receptors have historically been one of the most druggable classes of cellular proteins. The members of this large receptor gene family couple to primary effectors, G proteins, that have built in mechanisms for regeneration and amplification of signaling with each engagement of receptor and ligand, a kinetic event in itself. In recent years GPCRs, have been found to interact with arrestin proteins to initiate signal propagation in the absence of G protein interactions. This pinnacle observation has changed a previously held notion of the linear spectrum of GPCR efficacy and uncovered a new paradigm in GPCR research and drug discovery that relies on multidimensionality of GPCR signaling. Ligands were found that selectively confer activity in one pathway over another, and this phenomenon has been referred to as 'biased agonism' or 'functional selectivity'. While great strides in the understanding of this phenomenon have been made in recent years, two critical questions still dominate the field: How can we rationally design biased GPCR ligands, and ultimately, which physiological responses are due to G protein versus arrestin interactions? This review will discuss the current understanding of some of the key aspects of biased signaling that are related to these questions, including mechanistic insights in the nature of biased signaling and methods for measuring ligand bias, as well as relevant examples of drug discovery applications and medicinal chemistry strategies that highlight the challenges and opportunities in this rapidly evolving field.
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Affiliation(s)
- Zoran Rankovic
- Discovery Chemistry and Research Technologies, Eli Lilly and Company, 893 South Delaware Street, Indianapolis, IN 46285, USA.
| | - Tarsis F Brust
- Department of Molecular Therapeutics, and Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Laura M Bohn
- Department of Molecular Therapeutics, and Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA.
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A randomized, phase 2 study investigating TRV130, a biased ligand of the μ-opioid receptor, for the intravenous treatment of acute pain. Pain 2016; 157:264-272. [DOI: 10.1097/j.pain.0000000000000363] [Citation(s) in RCA: 151] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Jean-Charles PY, Snyder JC, Shenoy SK. Chapter One - Ubiquitination and Deubiquitination of G Protein-Coupled Receptors. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2016; 141:1-55. [PMID: 27378754 DOI: 10.1016/bs.pmbts.2016.05.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The seven-transmembrane containing G protein-coupled receptors (GPCRs) constitute the largest family of cell-surface receptors. Transmembrane signaling by GPCRs is fundamental to many aspects of physiology including vision, olfaction, cardiovascular, and reproductive functions as well as pain, behavior and psychomotor responses. The duration and magnitude of signal transduction is tightly controlled by a series of coordinated trafficking events that regulate the cell-surface expression of GPCRs at the plasma membrane. Moreover, the intracellular trafficking profiles of GPCRs can correlate with the signaling efficacy and efficiency triggered by the extracellular stimuli that activate GPCRs. Of the various molecular mechanisms that impart selectivity, sensitivity and strength of transmembrane signaling, ubiquitination of the receptor protein plays an important role because it defines both trafficking and signaling properties of the activated GPCR. Ubiquitination of proteins was originally discovered in the context of lysosome-independent degradation of cytosolic proteins by the 26S proteasome; however a large body of work suggests that ubiquitination also orchestrates the downregulation of membrane proteins in the lysosomes. In the case of GPCRs, such ubiquitin-mediated lysosomal degradation engenders long-term desensitization of transmembrane signaling. To date about 40 GPCRs are known to be ubiquitinated. For many GPCRs, ubiquitination plays a major role in postendocytic trafficking and sorting to the lysosomes. This chapter will focus on the patterns and functional roles of GPCR ubiquitination, and will describe various molecular mechanisms involved in GPCR ubiquitination.
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Affiliation(s)
- P-Y Jean-Charles
- Department of Medicine (Cardiology), Duke University Medical Center, Durham, NC, United States
| | - J C Snyder
- Department of Cell Biology, Duke University Medical Center, Durham, NC, United States
| | - S K Shenoy
- Department of Medicine (Cardiology), Duke University Medical Center, Durham, NC, United States; Department of Cell Biology, Duke University Medical Center, Durham, NC, United States.
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Convertino M, Samoshkin A, Viet CT, Gauthier J, Li Fraine SP, Sharif-Naeini R, Schmidt BL, Maixner W, Diatchenko L, Dokholyan NV. Differential Regulation of 6- and 7-Transmembrane Helix Variants of μ-Opioid Receptor in Response to Morphine Stimulation. PLoS One 2015; 10:e0142826. [PMID: 26554831 PMCID: PMC4640872 DOI: 10.1371/journal.pone.0142826] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 10/27/2015] [Indexed: 11/18/2022] Open
Abstract
The pharmacological effect of opioids originates, at the cellular level, by their interaction with the μ-opioid receptor (mOR) resulting in the regulation of voltage-gated Ca2+ channels and inwardly rectifying K+ channels that ultimately modulate the synaptic transmission. Recently, an alternative six trans-membrane helix isoform of mOR, (6TM-mOR) has been identified, but its function and signaling are still largely unknown. Here, we present the structural and functional mechanisms of 6TM-mOR signaling activity upon binding to morphine. Our data suggest that despite the similarity of binding modes of the alternative 6TM-mOR and the dominant seven trans-membrane helix variant (7TM-mOR), the interaction with morphine generates different dynamic responses in the two receptors, thus, promoting the activation of different mOR-specific signaling pathways. We characterize a series of 6TM-mOR-specific cellular responses, and observed that they are significantly different from those for 7TM-mOR. Morphine stimulation of 6TM-mOR does not promote a cellular cAMP response, while it increases the intracellular Ca2+ concentration and reduces the cellular K+ conductance. Our findings indicate that 6TM-mOR has a unique contribution to the cellular opioid responses. Therefore, it should be considered as a relevant target for the development of novel pharmacological tools and medical protocols involving the use of opioids.
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Affiliation(s)
- Marino Convertino
- Biochemistry and Biophysics Department, University of North Carolina, 120 Mason Farm Road, Chapel Hill, NC, United States of America, 27599
| | - Alexander Samoshkin
- Alan Edwards Centre for Research on Pain, McGill University, 740 Dr. Penfield Avenue, Montreal, Quebec, Canada, H3A 0G1
| | - Chi T Viet
- Bluestone Center for Clinic Research, New York University, New York, NY, United States of America, 10010
| | - Josee Gauthier
- Center for Pain Research and Innovation, University of North Carolina, 385 S. Columbia Street, Chapel Hill, NC, United States of America, 27599
| | - Steven P Li Fraine
- Department of Physiology and Cell Information Systems, McGill University, 3649 Promenade Sir William Osler, Montreal, Quebec, Canada, H3G 0B1
| | - Reza Sharif-Naeini
- Department of Physiology and Cell Information Systems, McGill University, 3649 Promenade Sir William Osler, Montreal, Quebec, Canada, H3G 0B1
| | - Brian L Schmidt
- Bluestone Center for Clinic Research, New York University, New York, NY, United States of America, 10010
| | - William Maixner
- Center for Pain Research and Innovation, University of North Carolina, 385 S. Columbia Street, Chapel Hill, NC, United States of America, 27599
| | - Luda Diatchenko
- Alan Edwards Centre for Research on Pain, McGill University, 740 Dr. Penfield Avenue, Montreal, Quebec, Canada, H3A 0G1
| | - Nikolay V Dokholyan
- Biochemistry and Biophysics Department, University of North Carolina, 120 Mason Farm Road, Chapel Hill, NC, United States of America, 27599.,Center for Pain Research and Innovation, University of North Carolina, 385 S. Columbia Street, Chapel Hill, NC, United States of America, 27599
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Thompson GL, Lane JR, Coudrat T, Sexton PM, Christopoulos A, Canals M. Biased Agonism of Endogenous Opioid Peptides at the μ-Opioid Receptor. Mol Pharmacol 2015; 88:335-46. [PMID: 26013541 DOI: 10.1124/mol.115.098848] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 05/26/2015] [Indexed: 01/14/2023] Open
Abstract
Biased agonism is having a major impact on modern drug discovery, and describes the ability of distinct G protein-coupled receptor (GPCR) ligands to activate different cell signaling pathways, and to result in different physiologic outcomes. To date, most studies of biased agonism have focused on synthetic molecules targeting various GPCRs; however, many of these receptors have multiple endogenous ligands, suggesting that "natural" bias may be an unappreciated feature of these GPCRs. The μ-opioid receptor (MOP) is activated by numerous endogenous opioid peptides, remains an attractive therapeutic target for the treatment of pain, and exhibits biased agonism in response to synthetic opiates. The aim of this study was to rigorously assess the potential for biased agonism in the actions of endogenous opioids at the MOP in a common cellular background, and compare these to the effects of the agonist d-Ala2-N-MePhe4-Gly-ol enkephalin (DAMGO). We investigated activation of G proteins, inhibition of cAMP production, extracellular signal-regulated kinase 1 and 2 phosphorylation, β-arrestin 1/2 recruitment, and MOP trafficking, and applied a novel analytical method to quantify biased agonism. Although many endogenous opioids displayed signaling profiles similar to that of DAMGO, α-neoendorphin, Met-enkephalin-Arg-Phe, and the putatively endogenous peptide endomorphin-1 displayed particularly distinct bias profiles. These may represent examples of natural bias if it can be shown that they have different signaling properties and physiologic effects in vivo compared with other endogenous opioids. Understanding how endogenous opioids control physiologic processes through biased agonism can reveal vital information required to enable the design of biased opioids with improved pharmacological profiles and treat diseases involving dysfunction of the endogenous opioid system.
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Affiliation(s)
- Georgina L Thompson
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (G.L.T., J.R.L., T.C., P.M.S., A.C., M.C.); and Defence Science and Technology Organisation, Department of Defence, Fishermans Bend, Victoria, Australia (G.L.T.)
| | - J Robert Lane
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (G.L.T., J.R.L., T.C., P.M.S., A.C., M.C.); and Defence Science and Technology Organisation, Department of Defence, Fishermans Bend, Victoria, Australia (G.L.T.)
| | - Thomas Coudrat
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (G.L.T., J.R.L., T.C., P.M.S., A.C., M.C.); and Defence Science and Technology Organisation, Department of Defence, Fishermans Bend, Victoria, Australia (G.L.T.)
| | - Patrick M Sexton
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (G.L.T., J.R.L., T.C., P.M.S., A.C., M.C.); and Defence Science and Technology Organisation, Department of Defence, Fishermans Bend, Victoria, Australia (G.L.T.)
| | - Arthur Christopoulos
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (G.L.T., J.R.L., T.C., P.M.S., A.C., M.C.); and Defence Science and Technology Organisation, Department of Defence, Fishermans Bend, Victoria, Australia (G.L.T.)
| | - Meritxell Canals
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (G.L.T., J.R.L., T.C., P.M.S., A.C., M.C.); and Defence Science and Technology Organisation, Department of Defence, Fishermans Bend, Victoria, Australia (G.L.T.)
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Breivogel CS, Vaghela MS. The effects of beta-arrestin1 deletion on acute cannabinoid activity, brain cannabinoid receptors and tolerance to cannabinoids in mice. J Recept Signal Transduct Res 2015; 35:98-106. [PMID: 25779032 DOI: 10.3109/10799893.2014.1003659] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
CONTEXT Previous studies have indicated a role for beta-arrestin2 in the regulation of brain cannabinoid effects and cannabinoid CB1 receptors, but whether beta-arrestin1 has a role has not been investigated. OBJECTIVE To determine the role of beta-arrestin1 in cannabinoid activity. MATERIALS AND METHODS Beta-arrestin1 -/- mice and their wild-type (+/+) counterparts were assayed for antinociceptive and temperature-decreasing effects of two ligands, Δ(9)-tetrahydrocannabinol (THC) and CP55940, after both single and repeated administration. In vitro assays examined the effects of deletion on CB1 receptor density, agonist-binding and G-protein activation. RESULTS Deletion of beta-arrestin1 diminished the effects of CP55940 in both antinociception (latency to tail withdrawal) and temperature-depression assays in mice. However, deleting beta-arrestin1 had no effect on the actions of THC in either assay. Antagonist radioligand ([(3)H]SR141716A) saturation binding indicated no difference between beta-arrestin1 +/+ and -/- mice in the density or affinity for cannabinoid CB1 receptors in brain membranes. CP55940 agonist binding in brain membranes from beta-arrestin1 +/+ mice exhibited high- and intermediate-affinity sites, but beta-arrestin1 -/- membranes exhibited an additional site with low affinity. CP55940 produced greater stimulation of [(35)S]GTPγS binding to membranes from whole brain of beta-arrestin1 -/- than +/+ mice. The rates of the development of tolerance to chronic THC or CP55940 administration did not appear to be affected by genotype. DISCUSSION Beta-arrestin1 appeared to mediate the actions of CP55940, but did not affect the activity of THC. CONCLUSION Beta-arrestin1 regulates cannabinoid CB1 receptor sensitivity in an agonist-selective manner, but may not be the primary mediator of tolerance to cannabinoid agonists.
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Affiliation(s)
- Chris S Breivogel
- Department of Pharmaceutical Sciences, Campbell University College of Pharmacy & Health Sciences , Buies Creek, NC , USA
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Mudgal A, Pasha S. Role of opioid receptor heterodimerization in pain modulation and tolerance development. World J Pharmacol 2015; 4:144-159. [DOI: 10.5497/wjp.v4.i1.144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 10/09/2014] [Accepted: 02/11/2015] [Indexed: 02/06/2023] Open
Abstract
Protein to protein interactions leading to homo/heteromerization of receptor is well documented in literature. These interactions leading to dimeric/oligomers formation of receptors are known to modulate their function, particularly in case of G-protein coupled receptors. The opioid receptor heteromers having changed pharmacological properties than the constituent protomers provides preferences for novel drug targets that could lead to potential analgesic activity devoid of tolerance and physical dependence. Heterodimerization of opioid receptors appears to generate novel binding properties with improved specificity and lack of side effects. Further the molecules which can interact simultaneously to both the protomers of the heteromer, or to both the binding sites (orthosteric and allosteric) of a receptor protein could be potential therapeutic molecules. This review highlights the recent advancements in exploring the plausible role of heteromerization of opioid receptors in induction of tolerance free antinociception.
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Brust TF, Hayes MP, Roman DL, Burris KD, Watts VJ. Bias analyses of preclinical and clinical D2 dopamine ligands: studies with immediate and complex signaling pathways. J Pharmacol Exp Ther 2014; 352:480-93. [PMID: 25539635 DOI: 10.1124/jpet.114.220293] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
G protein-coupled receptors (GPCRs) often activate multiple signaling pathways, and ligands may evoke functional responses through individual pathways. These unique responses provide opportunities for biased or functionally selective ligands to preferentially modulate one signaling pathway over another. Studies with several GPCRs have suggested that selective activation of signaling pathways downstream of a GPCR may lead to safer and more effective drug therapies. The dopamine D2 receptor (D2R) is one of the main drug targets in the therapies for Parkinson's disease and schizophrenia. Recent studies suggest that selective modulation of individual signaling pathways downstream of the D2R may lead to safer antipsychotic drugs. In the present study, immediate effectors of the D2R (i.e., Gαi/o, Gβγ, β-arrestin recruitment) and more complex signaling pathways (i.e., extracellular signal-regulated kinase phosphorylation, heterologous sensitization, and dynamic mass redistribution) were examined in response to a series of D2R ligands. This was accomplished using Chinese hamster ovary cells stably expressing the human D2L dopamine receptor in the PathHunter β-Arrestin GPCR Assay Platform. The use of a uniform cellular background was designed to eliminate potential confounds associated with cell-to-cell variability, including expression levels of receptor as well as other components of signal transduction, including G protein subunits. Several well characterized and clinically relevant D2R ligands were evaluated across each signaling pathway in this cellular model. The most commonly used methods to measure ligand bias were compared. Functional selectivity analyses were also used as tools to explore the relative contribution of immediate D2R effectors for the activation of more complex signaling pathways.
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Affiliation(s)
- Tarsis F Brust
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, Indiana (T.F.B., V.J.W.); Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, Iowa (M.P.H., D.L.R.); and Quantitative Biology, Eli Lilly and Company, Indianapolis, Indiana (K.D.B.)
| | - Michael P Hayes
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, Indiana (T.F.B., V.J.W.); Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, Iowa (M.P.H., D.L.R.); and Quantitative Biology, Eli Lilly and Company, Indianapolis, Indiana (K.D.B.)
| | - David L Roman
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, Indiana (T.F.B., V.J.W.); Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, Iowa (M.P.H., D.L.R.); and Quantitative Biology, Eli Lilly and Company, Indianapolis, Indiana (K.D.B.)
| | - Kevin D Burris
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, Indiana (T.F.B., V.J.W.); Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, Iowa (M.P.H., D.L.R.); and Quantitative Biology, Eli Lilly and Company, Indianapolis, Indiana (K.D.B.)
| | - Val J Watts
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, Indiana (T.F.B., V.J.W.); Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, Iowa (M.P.H., D.L.R.); and Quantitative Biology, Eli Lilly and Company, Indianapolis, Indiana (K.D.B.)
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Chilmonczyk Z, Bojarski AJ, Sylte I. Ligand-directed trafficking of receptor stimulus. Pharmacol Rep 2014; 66:1011-21. [DOI: 10.1016/j.pharep.2014.06.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 04/28/2014] [Accepted: 06/05/2014] [Indexed: 01/14/2023]
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Yang J, Yang H, Du X, Ma Q, Song J, Chen M, Dong Y, Ma L, Zheng P. Morphine and DAMGO produce an opposite effect on presynaptic glutamate release via different downstream pathways of μ opioid receptors in the basolateral amygdala. Neuropharmacology 2014; 86:353-61. [DOI: 10.1016/j.neuropharm.2014.08.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 08/25/2014] [Accepted: 08/26/2014] [Indexed: 01/16/2023]
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Aoki Y, Mizoguchi H, Watanabe C, Takeda K, Sakurada T, Sakurada S. Potential involvement of μ-opioid receptor dysregulation on the reduced antinociception of morphine in the inflammatory pain state in mice. J Pharmacol Sci 2014; 124:258-66. [PMID: 24553404 DOI: 10.1254/jphs.13242fp] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
The antinociceptive effect of morphine in the inflammatory pain state was described in the von Frey filament test using the complete Freund's adjuvant (CFA)-induced mouse inflammatory pain model. After an i.pl. injection of CFA, mechanical allodynia was observed in the ipsilateral paw. The antinociceptive effect of morphine injected s.c. and i.t. against mechanical allodynia was reduced bilaterally at 1 day and 4 days after the CFA pretreatment. The expression level of mRNA for μ-opioid receptors at 1 day after the CFA pretreatment was reduced bilaterally in the lumbar spinal cord and dorsal root ganglion (DRG). In contrast, the protein level of μ-opioid receptors at 1 day after CFA pretreatment was decreased in the ipsilateral side in the DRG but not the lumbar spinal cord. Single or repeated i.t. pretreatment with the protein kinase Cα (PKCα) inhibitor Ro-32-0432 completely restored the reduced morphine antinociception in the contralateral paw but only partially restored it in the ipsilateral paw in the inflammatory pain state. In conclusion, reduced morphine antinociception against mechanical allodynia in the inflammatory pain state is mainly mediated via a decrease in μ-opioid receptors in the ipsilateral side and via the desensitization of μ-opioid receptors in the contralateral side by PKCα-induced phosphorylation.
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Affiliation(s)
- Yuta Aoki
- Department of Physiology and Anatomy, Tohoku Pharmaceutical University, Japan
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Lamberts JT, Traynor JR. Opioid receptor interacting proteins and the control of opioid signaling. Curr Pharm Des 2014; 19:7333-47. [PMID: 23448476 DOI: 10.2174/138161281942140105160625] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 02/18/2013] [Indexed: 12/31/2022]
Abstract
Opioid receptors are seven-transmembrane domain receptors that couple to intracellular signaling molecules by activating heterotrimeric G proteins. However, the receptor and G protein do not function in isolation but their activities are modulated by several accessory and scaffolding proteins. Examples include arrestins, kinases, and regulators of G protein signaling proteins. Accessory proteins contribute to the observed potency and efficacy of agonists, but also to the direction of signaling and the phenomenon of biased agonism. This review will present current knowledge of such proteins and how they may provide targets for future drug design.
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Affiliation(s)
| | - John R Traynor
- Department of Pharmacology, University of Michigan Medical School, 1301 MSRB III, 1150 West Medical Center Drive, Ann Arbor, MI 48109-5632, USA.
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Cooke AE, Oldfield S, Krasel C, Mundell SJ, Henderson G, Kelly E. Morphine-induced internalization of the L83I mutant of the rat μ-opioid receptor. Br J Pharmacol 2014; 172:593-605. [PMID: 24697554 DOI: 10.1111/bph.12709] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Revised: 03/17/2014] [Accepted: 03/26/2014] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND AND PURPOSE Naturally occurring single-nucleotide polymorphisms (SNPs) within GPCRs can result in alterations in various pharmacological parameters. Understanding the regulation and function of endocytic trafficking of the μ-opioid receptor (MOP receptor) is of great importance given its implication in the development of opioid tolerance. This study has compared the agonist-dependent trafficking and signalling of L83I, the rat orthologue of a naturally occurring variant of the MOP receptor. EXPERIMENTAL APPROACH Cell surface elisa, confocal microscopy and immunoprecipitation assays were used to characterize the trafficking properties of the MOP-L83I variant in comparison with the wild-type receptor in HEK 293 cells. Functional assays were used to compare the ability of the L83I variant to signal to several downstream pathways. KEY RESULTS Morphine-induced internalization of the L83I MOP receptor was markedly increased in comparison with the wild-type receptor. The altered trafficking of this variant was found to be specific to morphine and was both G-protein receptor kinase- and dynamin-dependent. The enhanced internalization of L83I variant in response to morphine was not due to increased phosphorylation of serine 375, arrestin association or an increased ability to signal. CONCLUSIONS AND IMPLICATIONS These results suggest that morphine promotes a specific conformation of the L83I variant that makes it more liable to internalize in response to morphine, unlike the wild-type receptor that undergoes significantly less morphine-stimulated internalization, providing an example of a ligand-selective biased receptor. The presence of this SNP within an individual may consequently affect the development of tolerance and analgesic responses. 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 E Cooke
- School of Physiology and Pharmacology, University of Bristol, Bristol, BS8 1TD, UK
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Jaremko KM, Thompson NL, Reyes BAS, Jin J, Ebersole B, Jenney CB, Grigson PS, Levenson R, Berrettini WH, Van Bockstaele EJ. Morphine-induced trafficking of a mu-opioid receptor interacting protein in rat locus coeruleus neurons. Prog Neuropsychopharmacol Biol Psychiatry 2014; 50:53-65. [PMID: 24333843 PMCID: PMC3928604 DOI: 10.1016/j.pnpbp.2013.12.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2013] [Revised: 11/26/2013] [Accepted: 12/05/2013] [Indexed: 12/14/2022]
Abstract
Opiate addiction is a devastating health problem, with approximately 2million people currently addicted to heroin or non-medical prescription opiates in the United States alone. In neurons, adaptations in cell signaling cascades develop following opioid actions at the mu opioid receptor (MOR). A novel putative target for intervention involves interacting proteins that may regulate trafficking of MOR. Morphine has been shown to induce a re-distribution of a MOR-interacting protein Wntless (WLS, a transport molecule necessary for secretion of neurotrophic Wnt proteins), from cytoplasmic to membrane compartments in rat striatal neurons. Given its opiate-sensitivity and its well-characterized molecular and cellular adaptations to morphine exposure, we investigated the anatomical distribution of WLS and MOR in the rat locus coeruleus (LC)-norepinephrine (NE) system. Dual immunofluorescence microscopy was used to test the hypothesis that WLS is localized to noradrenergic neurons of the LC and that WLS and MOR co-exist in common LC somatodendritic processes, providing an anatomical substrate for their putative interactions. We also hypothesized that morphine would influence WLS distribution in the LC. Rats received saline, morphine or the opiate agonist [d-Ala2, N-Me-Phe4, Gly-ol5]-enkephalin (DAMGO), and tissue sections through the LC were processed for immunogold-silver detection of WLS and MOR. Statistical analysis showed a significant re-distribution of WLS to the plasma membrane following morphine treatment in addition to an increase in the proximity of gold-silver labels for MOR and WLS. Following DAMGO treatment, MOR and WLS were predominantly localized within the cytoplasmic compartment when compared to morphine and control. In a separate cohort of rats, brains were obtained from saline-treated or heroin self-administering male rats for pulldown co-immunoprecipitation studies. Results showed an increased association of WLS and MOR following heroin exposure. As the LC-NE system is important for cognition as well as decisions underlying substance abuse, adaptations in WLS trafficking and expression may play a role in modulating MOR function in the LC and contribute to the negative sequelae of opiate exposure on executive function.
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Affiliation(s)
- Kellie M Jaremko
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA 19102, United States
| | - Nicholas L Thompson
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA 19102, United States
| | - Beverly A S Reyes
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA 19102, United States.
| | - Jay Jin
- Department of Pharmacology, Penn State College of Medicine, Hershey, PA 17033, United States
| | - Brittany Ebersole
- Department of Pharmacology, Penn State College of Medicine, Hershey, PA 17033, United States
| | - Christopher B Jenney
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, PA 17033, United States
| | - Patricia S Grigson
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, PA 17033, United States
| | - Robert Levenson
- Department of Pharmacology, Penn State College of Medicine, Hershey, PA 17033, United States
| | - Wade H Berrettini
- Department of Psychiatry, Center for Neurobiology and Behavior, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, United States
| | - Elisabeth J Van Bockstaele
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA 19102, United States
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45
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Zhou L, Bohn LM. Functional selectivity of GPCR signaling in animals. Curr Opin Cell Biol 2013; 27:102-8. [PMID: 24680435 DOI: 10.1016/j.ceb.2013.11.010] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Accepted: 11/24/2013] [Indexed: 12/13/2022]
Abstract
At one time, G protein-coupled receptors were envisioned to simply relay either inhibitory or stimulatory binary signals through engaging particular G proteins. These receptors are now viewed as complex, multidimensional triggers of a variety of potential signaling cascades. This review will showcase current attempts to elucidate biased signaling and functional selectivity in tissues and organs as well as in the whole animal. In addition, it will emphasize the challenges that are inherent in attributing bias in a living system as well as offer opinions as to the manner in which these problems may be approached.
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Affiliation(s)
- Lei Zhou
- Department of Molecular Therapeutics, The Scripps Research Institute, Jupiter, FL 33458, USA; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Laura M Bohn
- Department of Molecular Therapeutics, The Scripps Research Institute, Jupiter, FL 33458, USA; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA.
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46
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Breivogel CS, Puri V, Lambert JM, Hill DK, Huffman JW, Razdan RK. The influence of beta-arrestin2 on cannabinoid CB1receptor coupling to G-proteins and subcellular localization and relative levels of beta-arrestin1 and 2 in mouse brain. J Recept Signal Transduct Res 2013; 33:367-79. [DOI: 10.3109/10799893.2013.838787] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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47
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Zheng LH, Wang CH, Shang SJ, Zhang XY, Wang YS, Wu QH, Hu MQ, Chai ZY, Wu X, Zheng H, Zhang C, Wang LC, Xiong W, Zhou Z. Real-time endocytosis imaging as a rapid assay of ligand-GPCR binding in single cells. Am J Physiol Cell Physiol 2013; 305:C751-60. [DOI: 10.1152/ajpcell.00335.2012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Most G protein-coupled receptors (GPCRs) do not generate membrane currents in response to ligand-receptor binding (LRB). Here, we describe a novel technique using endocytosis as a bioassay that can detect activation of a GPCR in a way analogous to patch-clamp recording of an ion channel in a living cell. The confocal imaging technique, termed FM endocytosis imaging (FEI), can record ligand-GPCR binding with high temporal (second) and spatial (micrometer) resolution. LRB leads to internalization of an endocytic vesicle, which can be labeled by a styryl FM dye and visualized as a fluorescent spot. Distinct from the green fluorescence protein-labeling method, FEI can detect LRB endocytosis mediated by essentially any receptors (GPCRs or receptors of tyrosine kinase) in a native cell/cell line. Three modified versions of FEI permit promising applications in functional GPCR studies and drug screening in living cells: 1) LRB can be recorded in “real time” (time scale of seconds); 2) internalized vesicles mediated by different GPCRs can be discriminated by different colors; and 3) a high throughput method can screen ligands of a specific GPCR.
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Affiliation(s)
- Liang-Hong Zheng
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research, Institute of Molecular Medicine and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Chang-He Wang
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research, Institute of Molecular Medicine and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Shu-Jiang Shang
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research, Institute of Molecular Medicine and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Xiao-Yu Zhang
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research, Institute of Molecular Medicine and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Ye-Shi Wang
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research, Institute of Molecular Medicine and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Qi-Hui Wu
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research, Institute of Molecular Medicine and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Mei-Qin Hu
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research, Institute of Molecular Medicine and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Zu-Yin Chai
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research, Institute of Molecular Medicine and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Xi Wu
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research, Institute of Molecular Medicine and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Hui Zheng
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research, Institute of Molecular Medicine and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Chen Zhang
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research, Institute of Molecular Medicine and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Lie-Cheng Wang
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research, Institute of Molecular Medicine and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Wei Xiong
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research, Institute of Molecular Medicine and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Zhuan Zhou
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research, Institute of Molecular Medicine and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
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Abstract
Opiates are among the oldest medications available to manage a number of medical problems. Although pain is the current focus, early use initially focused upon the treatment of dysentery. Opium contains high concentrations of both morphine and codeine, along with thebaine, which is used in the synthesis of a number of semisynthetic opioid analgesics. Thus, it is not surprising that new agents were initially based upon the morphine scaffold. The concept of multiple opioid receptors was first suggested almost 50 years ago (Martin, 1967), opening the possibility of new classes of drugs, but the morphine-like agents have remained the mainstay in the medical management of pain. Termed mu, our understanding of these morphine-like agents and their receptors has undergone an evolution in thinking over the past 35 years. Early pharmacological studies identified three major classes of receptors, helped by the discovery of endogenous opioid peptides and receptor subtypes-primarily through the synthesis of novel agents. These chemical biologic approaches were then eclipsed by the molecular biology revolution, which now reveals a complexity of the morphine-like agents and their receptors that had not been previously appreciated.
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Affiliation(s)
- Gavril W Pasternak
- Memorial Sloan-Kettering Cancer Center, 1275 York Ave, New York, NY 10065.
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49
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Inhibition of Gβγ-subunit signaling potentiates morphine-induced antinociception but not respiratory depression, constipation, locomotion, and reward. Behav Pharmacol 2013; 24:144-52. [PMID: 23412114 DOI: 10.1097/fbp.0b013e32835f3d2f] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Inhibition of Gβγ-subunit signaling to phospholipase C β3 has been shown to potentiate morphine-mediated antinociception while attenuating the development of tolerance and dependence in mice. The objective of this study was to determine the effect of Gβγ-subunit inhibition on antinociception and other pharmacological effects, such as respiratory depression, constipation, and hyperlocomotion, mediated by the μ-opioid receptor. The Gβγ-subunit inhibitor, gallein, was administered to C57BL/6J mice by intraperitoneal injection before morphine, and data were compared with mice treated with vehicle, morphine, or gallein alone. Morphine-induced antinociception was measured using the 55°C warm-water tail-withdrawal test. Pretreatment with gallein produced a dose-dependent potentiation of morphine-mediated antinociception, producing up to a 10-fold leftward shift in the morphine dose-response curve and extending the duration of antinociception induced by a single dose of morphine. Gallein pretreatment also prevented acute antinociceptive tolerance induced by morphine. In contrast, the dose-dependent respiratory depression and hyperlocomotion induced by morphine were not potentiated by gallein pretreatment. Similarly, gallein pretreatment did not potentiate morphine-conditioned place preference responses or morphine-induced constipation, as measured as a reduction in excreta. These results suggest that selectively inhibiting Gβγ-mediated signaling may selectively increase μ-opioid receptor-mediated antinociception without matching increases in adverse physiological effects.
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50
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Ghanemi A. Targeting G protein coupled receptor-related pathways as emerging molecular therapies. Saudi Pharm J 2013; 23:115-29. [PMID: 25972730 PMCID: PMC4420995 DOI: 10.1016/j.jsps.2013.07.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Accepted: 07/29/2013] [Indexed: 12/20/2022] Open
Abstract
G protein coupled receptors (GPCRs) represent the most important targets in modern pharmacology because of the different functions they mediate, especially within brain and peripheral nervous system, and also because of their functional and stereochemical properties. In this paper, we illustrate, via a variety of examples, novel advances about the GPCR-related molecules that have been shown to play diverse roles in GPCR pathways and in pathophysiological phenomena. We have exemplified how those GPCRs’ pathways are, or might constitute, potential targets for different drugs either to stimulate, modify, regulate or inhibit the cellular mechanisms that are hypothesized to govern some pathologic, physiologic, biologic and cellular or molecular aspects both in vivo and in vitro. Therefore, influencing such pathways will, undoubtedly, lead to different therapeutical applications based on the related pharmacological implications. Furthermore, such new properties can be applied in different fields. In addition to offering fruitful directions for future researches, we hope the reviewed data, together with the elements found within the cited references, will inspire clinicians and researchers devoted to the studies on GPCR’s properties.
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Affiliation(s)
- Abdelaziz Ghanemi
- Department of Pharmacology, China Pharmaceutical University, Nanjing 210009, China
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