1
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Roth BL, Krumm BE. Molecular glues as potential GPCR therapeutics. Biochem Pharmacol 2024:116402. [PMID: 38945274 DOI: 10.1016/j.bcp.2024.116402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 06/25/2024] [Accepted: 06/27/2024] [Indexed: 07/02/2024]
Abstract
"Molecular Glues" are defined as small molecules that can either be endogenous or synthetic which promote interactions between proteins at their interface. Allosteric modulators, specifically GPCR allosteric modulators, can promote both the association and the dissociation of a given receptor's transducer but accomplishes this "at a distance" from the interface. However, recent structures of GPCR G protein complexes in the presence of allosteric modulators indicate that some GPCR allosteric modulators can act as "molecular glues" interacting with both the receptor and the transducer at the interface biasing transducer signaling in both a positive and negative manner depending on the transducer. Given these phenomena we discuss the implications for this class of allosteric modulators to be used as molecular tools and for future drug development.
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Affiliation(s)
- Bryan L Roth
- Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; National Institute of Mental Health Psychoactive Drug Screening Program (NIMH PDSP), School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
| | - Brian E Krumm
- Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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2
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Che T, Roth BL. Molecular basis of opioid receptor signaling. Cell 2023; 186:5203-5219. [PMID: 37995655 PMCID: PMC10710086 DOI: 10.1016/j.cell.2023.10.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 10/13/2023] [Accepted: 10/27/2023] [Indexed: 11/25/2023]
Abstract
Opioids are used for pain management despite the side effects that contribute to the opioid crisis. The pursuit of non-addictive opioid analgesics remains unattained due to the unresolved intricacies of opioid actions, receptor signaling cascades, and neuronal plasticity. Advancements in structural, molecular, and computational tools illuminate the dynamic interplay between opioids and opioid receptors, as well as the molecular determinants of signaling pathways, which are potentially interlinked with pharmacological responses. Here, we review the molecular basis of opioid receptor signaling with a focus on the structures of opioid receptors bound to endogenous peptides or pharmacological agents. These insights unveil specific interactions that dictate ligand selectivity and likely their distinctive pharmacological profiles. Biochemical analysis further unveils molecular features governing opioid receptor signaling. Simultaneously, the synergy between computational biology and medicinal chemistry continues to expedite the discovery of novel chemotypes with the promise of yielding more efficacious and safer opioid compounds.
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Affiliation(s)
- Tao Che
- Department of Anesthesiology, Washington University School of Medicine, Saint Louis, MO 63110, USA; Center for Clinical Pharmacology, University of Health Sciences & Pharmacy and Washington University School of Medicine, Saint Louis, MO 63110, USA.
| | - Bryan L Roth
- Department of Pharmacology, University of North Carolina Chapel Hill School of Medicine, Chapel Hill 27599, NC, USA.
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3
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Karkhanis AN, West AM, Jones SR. Kappa opioid receptor agonist U50,488 inhibits dopamine more in caudal than rostral nucleus accumbens core. Basic Clin Pharmacol Toxicol 2023; 133:526-534. [PMID: 37539456 DOI: 10.1111/bcpt.13929] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 06/07/2023] [Accepted: 07/14/2023] [Indexed: 08/05/2023]
Abstract
The nucleus accumbens (NAc) core is involved in regulating stress and shaping reward seeking behaviours. Multiple neuromodulators, including dynorphin/kappa opioid receptor (KOR) and dopamine systems, converge in this area to influence behavioural outcomes. KOR activation acutely inhibits dopamine release and chronically depresses overall dopamine transmission. Recently, studies in the NAc shell have revealed that the impact of KOR activation on behaviour is regionally specific, and these rostro-caudal differences are likely driven by greater control of KORs over dopamine inhibition in the caudal compared with rostral subregion. Given the importance of NAc core, particularly the interaction between KORs and dopamine in regulating reward seeking behaviours, we examined the impact of KOR activation on dopamine release and uptake along the rostro-caudal axis in the NAc core of male and female mice. Using ex vivo fast scan cyclic voltammetry, we observed that KOR mediated inhibition of dopamine release was significantly greater in caudal compared with rostral NAc core with no significant sex differences observed. These data suggest that KORs regulate dopamine release differentially along the rostro-caudal axis, providing a new axis on which to examine the process by which the KOR/dopamine system controls reward encoding.
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Affiliation(s)
| | - Alyssa M West
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
| | - Sara R Jones
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
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4
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Kappa-opioid receptor-dependent changes in dopamine and anxiety-like or approach-avoidance behavior occur differentially across the nucleus accumbens shell rostro-caudal axis. Neuropharmacology 2020; 181:108341. [PMID: 33011200 DOI: 10.1016/j.neuropharm.2020.108341] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 09/28/2020] [Accepted: 09/29/2020] [Indexed: 01/24/2023]
Abstract
Neural circuit engagement within the nucleus accumbens (NAc) shell is implicated in the regulation of both negative and positive affect. Classically, the dynorphin/kappa opioid receptor (KOR) system in the NAc was believed to promote aversion, while dopamine was viewed as interacting with reward behavior, and KOR activation was known to inhibit dopamine release. Recently, however, both the KOR and dopamine systems have, separately, been shown to have differential effects across the rostro-caudal axis of the NAc shell on hedonic responses. Whether or not this is due to interactions between KORs and dopamine, and if it extends to anxiety-like or approach-avoidance behaviors, remains to be determined. In this study, we examined in rats the relationship between the KOR and dopamine systems in both the rostral and caudal NAc shell using ex vivo fast scan cyclic voltammetry and the impact of KOR activation on affective behavior using exploration-based tasks. We report here that activation of KORs in the caudal NAc shell significantly inhibits dopamine release, stimulates rearing behavior in a novel environment, increases anxiety-like or avoidance behavior, and reduces locomotor activity. In contrast, activation of KORs in the rostral NAc shell inhibits dopamine release to a lesser extent and instead reduces anxiety-like behavior or increases approach behavior. Taken together, these results indicate that there is heterogeneity across the rostro-caudal axis of the NAc shell in the effects of KOR stimulation on affective behaviors, and they suggest that this might be due to differences in KOR control over dopamine release.
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5
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Nguyen T, Gamage TF, Decker AM, Barrus D, Langston TL, Li JX, Thomas BF, Zhang Y. Synthesis and Pharmacological Evaluation of 1-Phenyl-3-Thiophenylurea Derivatives as Cannabinoid Type-1 Receptor Allosteric Modulators. J Med Chem 2019; 62:9806-9823. [PMID: 31596583 DOI: 10.1021/acs.jmedchem.9b01161] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We previously reported diarylurea derivatives as cannabinoid type-1 receptor (CB1) allosteric modulators, which were effective in attenuating cocaine-seeking behavior. Herein, we extended the structure-activity relationships of PSNCBAM-1 (2) at the central phenyl ring directly connected to the urea moiety. Replacement with a thiophene ring led to 11 with improved or comparable potencies in calcium mobilization, [35S]GTPγS binding, and cAMP assays, whereas substitution with nonaromatic rings led to significant attenuation of the modulatory activity. These compounds had no inverse agonism in [35S]GTPγS binding, a characteristic that is often thought to contribute to adverse psychiatric effects. While 11 had good metabolic stability in rat liver microsomes, it showed modest solubility and blood-brain barrier permeability. Compound 11 showed an insignificant attenuation of cocaine seeking behavior in rats, most likely due to its limited CNS penetration, suggesting that pharmacokinetics and distribution play a role in translating the in vitro efficacy to in vivo behavior.
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Affiliation(s)
- Thuy Nguyen
- Research Triangle Institute , Research Triangle Park , North Carolina 27709 , United States
| | - Thomas F Gamage
- Research Triangle Institute , Research Triangle Park , North Carolina 27709 , United States
| | - Ann M Decker
- Research Triangle Institute , Research Triangle Park , North Carolina 27709 , United States
| | - Daniel Barrus
- Research Triangle Institute , Research Triangle Park , North Carolina 27709 , United States
| | - Tiffany L Langston
- Research Triangle Institute , Research Triangle Park , North Carolina 27709 , United States
| | - Jun-Xu Li
- Department of Pharmacology and Toxicology , University of Buffalo, the State University of New York , Buffalo , New York 14214 , United States
| | - Brian F Thomas
- Research Triangle Institute , Research Triangle Park , North Carolina 27709 , United States
| | - Yanan Zhang
- Research Triangle Institute , Research Triangle Park , North Carolina 27709 , United States
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6
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Ragnarsson L, Andersson Å, Thomas WG, Lewis RJ. Mutations in the NPxxY motif stabilize pharmacologically distinct conformational states of the α 1B- and β 2-adrenoceptors. Sci Signal 2019; 12:12/572/eaas9485. [PMID: 30862702 DOI: 10.1126/scisignal.aas9485] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
G protein-coupled receptors (GPCRs) convert extracellular stimuli to intracellular responses that regulate numerous physiological processes. Crystallographic and biophysical advances in GPCR structural analysis have aided investigations of structure-function relationships that clarify our understanding of these dynamic receptors, but the molecular mechanisms associated with activation and signaling for individual GPCRs may be more complex than was previously appreciated. Here, we investigated the proposed water-mediated, hydrogen-bonded activation switch between the conserved NPxxY motif on transmembrane helix 7 (TMH7) and a conserved tyrosine in TMH5, which contributes to α1B-adrenoceptor (α1B-AR) and β2-AR activation. Disrupting this bond by mutagenesis stabilized the α1B-AR and the β2-AR in inactive-state conformations, which displayed decreased agonist potency for stimulating downstream IP1 and cAMP signaling, respectively. Compared to that for wild-type receptors, agonist-mediated β-arrestin recruitment was substantially reduced or abolished for all α1B-AR and β2-AR inactive-state mutants. However, the inactive-state β2-ARs exhibited decreased agonist affinity, whereas the inactive-state α1B-ARs had enhanced agonist affinity. Conversely, antagonist affinity was unchanged for inactive-state conformations of both α1B-AR and β2-AR. Removing the influence of agonist affinity on agonist potency gave a measure of signaling efficacy, which was markedly decreased for the α1B-AR mutants but little altered for the β2-AR mutants. These findings highlight the pharmacological heterogeneity of inactive-state GPCR conformations, which may facilitate the rational design of drugs that target distinct conformational states of GPCRs.
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Affiliation(s)
- Lotten Ragnarsson
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia.
| | - Åsa Andersson
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Walter G Thomas
- School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Richard J Lewis
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia.
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7
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Abstract
From the pharmacological point of view, allosteric modulators may present numerous advantages over orthosteric ligands. Growing availability of novel tools and experimental data provides a tempting opportunity to apply computational methods to improve known modulators and design novel ones. However, recent progress in understanding of complexity of allostery increases awareness of problems involved in design of modulators with desired properties. Deeper insight into phenomena such as probe dependence, altering signaling bias with minor changes in ligand structure, as well as influence of subtle endogenous allosteric factors turns out to be fundamental. These effects make the design of a modulator with precise pharmacological outcome a very challenging task, and need to be taken into consideration throughout the design process. In this chapter, we focus on nuances of targeting GPCR allosteric sites in computational drug design efforts, in particular with application of docking, virtual screening, and molecular dynamics.
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8
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Abstract
INTRODUCTION The availability of different functional pharmacological assays has revealed that agonists for receptors that are pleiotropically coupled to multiple signaling pathways in the cell can emphasize signals to some pathways over others, i.e. can be biased toward certain signals. This, in turn, opens the possibility that molecules can be made to emphasize favorable signals, de-emphasize harmful signals or selectively block the ability of the natural agonist to produce unfavorable signals. Areas covered: This paper discusses the mechanism of biased signaling, the possible therapeutic implications of this effect, methods to quantify and measure bias and the current literature describing the translation of biased measure in vitro to in vivo systems. In addition, the challenges of exploiting this mechanism for therapy are outlined. Expert opinion: While this mechanism is well established and ubiquitous in pharmacology and easily measured in vitro, there are theoretical and practical hurdles to overcome to the fruitful utilization of signaling bias in therapeutic systems. There will be failures in the translation of biased molecules in vivo because of these challenges but hopefully also success and these latter translations hopefully will provide guidance in exploiting this effect further for therapy.
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Affiliation(s)
- Terry Kenakin
- a Department of Pharmacology , University of North Carolina School of Medicine , Chapel Hill , NC , USA
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9
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Resendez SL, Keyes PC, Day JJ, Hambro C, Austin CJ, Maina FK, Eidson LN, Porter-Stransky KA, Nevárez N, McLean JW, Kuhnmuench MA, Murphy AZ, Mathews TA, Aragona BJ. Dopamine and opioid systems interact within the nucleus accumbens to maintain monogamous pair bonds. eLife 2016; 5:e15325. [PMID: 27371827 PMCID: PMC4972541 DOI: 10.7554/elife.15325] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 07/01/2016] [Indexed: 01/23/2023] Open
Abstract
Prairie vole breeder pairs form monogamous pair bonds, which are maintained through the expression of selective aggression toward novel conspecifics. Here, we utilize behavioral and anatomical techniques to extend the current understanding of neural mechanisms that mediate pair bond maintenance. For both sexes, we show that pair bonding up-regulates mRNA expression for genes encoding D1-like dopamine (DA) receptors and dynorphin as well as enhances stimulated DA release within the nucleus accumbens (NAc). We next show that D1-like receptor regulation of selective aggression is mediated through downstream activation of kappa-opioid receptors (KORs) and that activation of these receptors mediates social avoidance. Finally, we also identified sex-specific alterations in KOR binding density within the NAc shell of paired males and demonstrate that this alteration contributes to the neuroprotective effect of pair bonding against drug reward. Together, these findings suggest motivational and valence processing systems interact to mediate the maintenance of social bonds.
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Affiliation(s)
- Shanna L Resendez
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, United States
- University of North Carolina, Chapel Hill, United States
| | - Piper C Keyes
- Department of Psychology, University of Michigan-Ann Arbor, Ann Arbor, United States
| | - Jeremy J Day
- Department of Neurobiology, University of Alabama at Birmingham, Birmangham, United States
| | - Caely Hambro
- Department of Psychology, University of Michigan-Ann Arbor, Ann Arbor, United States
| | - Curtis J Austin
- Department of Psychology, University of Michigan-Ann Arbor, Ann Arbor, United States
| | - Francis K Maina
- Department of Chemistry, Wayne State University, Detroit, United States
| | - Lori N Eidson
- Neuroscience Institute, Georgia State University, Atlanta, United States
| | - Kirsten A Porter-Stransky
- Department of Psychology, University of Michigan-Ann Arbor, Ann Arbor, United States
- Department of Human Genetics, Emory University, Atlanta, United States
| | - Natalie Nevárez
- Department of Psychology, University of Michigan-Ann Arbor, Ann Arbor, United States
| | - J William McLean
- Department of Neurobiology, University of Alabama at Birmingham, Birmangham, United States
| | - Morgan A Kuhnmuench
- Department of Psychology, University of Michigan-Ann Arbor, Ann Arbor, United States
| | - Anne Z Murphy
- Neuroscience Institute, Georgia State University, Atlanta, United States
| | - Tiffany A Mathews
- Department of Chemistry, Wayne State University, Detroit, United States
| | - Brandon J Aragona
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, United States
- Department of Psychology, University of Michigan-Ann Arbor, Ann Arbor, United States
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10
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Abstract
Over the past 50 years in pharmacology, an understanding of seven transmembrane (7TMR) function has been gained from the comparison of experimental data to receptor models. These models have been constructed from building blocks composed of systems consisting of series and parallel mass action binding reactions. Basic functions such as the the isomerization of receptors upon ligand binding, the sequential binding of receptors to membrane coupling proteins, and the selection of multiple receptor conformations have been combined in various ways to build receptor systems such as the ternary complex, extended ternary complex, and cubic ternary complex models for 7TMR function. Separately, the Black/Leff operational model has furnished an extremely valuable method of quantifying drug agonism. In the past few years, incorporation of the basic allosteric nature of 7TMRs has led to additional useful models of functional receptor allosteric mechanisms; these models yield valuable methods for quantifying allosteric effects. Finally, molecular dynamics has provided yet another new set of models describing the probability of formation of multiple receptor states; these radically new models are extremely useful in the prediction of functionally selective drug effects.
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Affiliation(s)
- Terry Kenakin
- Department of Pharmacology, University of North Carolina School of Medicine , 120 Mason Farm Road, Room 4042, Genetic Medicine Building, CB# 7365, Chapel Hill, North Carolina 27599-7365, United States
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11
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Pachov DV, Fonseca R, Arnol D, Bernauer J, van den Bedem H. Coupled Motions in β2AR:Gαs Conformational Ensembles. J Chem Theory Comput 2016; 12:946-56. [DOI: 10.1021/acs.jctc.5b00995] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Dimitar V. Pachov
- Department
of Chemistry, Stanford University, Stanford, California 94305, United States
- Division
of Biosciences, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, California 94025, United States
| | - Rasmus Fonseca
- Division
of Biosciences, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, California 94025, United States
- AMIB
INRIA - Bioinformatics group, LIX, École Polytechnique, 91128 Palaiseau, France
| | - Damien Arnol
- INRIA Saclay-Île de France, 1 rue Honoré d'Estienne
d'Orves, Bâtiment Alan Turing, Campus de l'École
Polytechnique, 91120 Palaiseau, France
- Laboratoire
d'Informatique de l'École Polytechnique (LIX), CNRS
UMR 7161, École Polytechnique, 91128 Palaiseau, France
| | - Julie Bernauer
- INRIA Saclay-Île de France, 1 rue Honoré d'Estienne
d'Orves, Bâtiment Alan Turing, Campus de l'École
Polytechnique, 91120 Palaiseau, France
- Laboratoire
d'Informatique de l'École Polytechnique (LIX), CNRS
UMR 7161, École Polytechnique, 91128 Palaiseau, France
| | - Henry van den Bedem
- Division
of Biosciences, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, California 94025, United States
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12
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Rosethorne EM, Bradley ME, Gherbi K, Sykes DA, Sattikar A, Wright JD, Renard E, Trifilieff A, Fairhurst RA, Charlton SJ. Long Receptor Residence Time of C26 Contributes to Super Agonist Activity at the Human β2 Adrenoceptor. Mol Pharmacol 2016; 89:467-75. [DOI: 10.1124/mol.115.101253] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 01/13/2016] [Indexed: 12/17/2022] Open
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13
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Jiang Y, Yuan Y, Zhang X, Liang T, Guo Y, Li M, Pu X. Use of network model to explore dynamic and allosteric properties of three GPCR homodimers. RSC Adv 2016. [DOI: 10.1039/c6ra18243g] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
We used an elastic network model and protein structure network to study three class A GPCR homodimers.
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Affiliation(s)
- Yuanyuan Jiang
- College of Chemistry
- Sichuan University
- Chengdu
- P. R. China
| | - Yuan Yuan
- College of Management
- Southwest University for Nationalities
- Chengdu 610064
- P. R. China
| | - Xi Zhang
- College of Chemistry
- Sichuan University
- Chengdu
- P. R. China
| | - Tao Liang
- College of Chemistry
- Sichuan University
- Chengdu
- P. R. China
| | - Yanzhi Guo
- College of Chemistry
- Sichuan University
- Chengdu
- P. R. China
| | - Menglong Li
- College of Chemistry
- Sichuan University
- Chengdu
- P. R. China
| | - Xumei Pu
- College of Chemistry
- Sichuan University
- Chengdu
- P. R. China
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14
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Kenakin T. The mass action equation in pharmacology. Br J Clin Pharmacol 2015; 81:41-51. [PMID: 26506455 DOI: 10.1111/bcp.12810] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2015] [Revised: 09/25/2015] [Accepted: 10/12/2015] [Indexed: 01/14/2023] Open
Abstract
The mass action equation is the building block from which all models of drug-receptor interaction are built. In the simplest case, the equation predicts a sigmoidal relationship between the amount of drug-receptor complex and the logarithm of the concentration of drug. The form of this function is also the same as most dose-response relationships in pharmacology (such as enzyme inhibition and the protein binding of drugs) but the potency term in dose-response relationships very often differs in meaning from the similar term in the simple mass action relationship. This is because (i) most pharmacological systems are collections of mass action reactions in series and/or in parallel and (ii) the important assumptions in the mass action reaction are violated in complex pharmacological systems. In some systems, the affinity of the receptor R for some ligand A is modified by interaction of the receptor with the allosteric ligand B and concomitantly the affinity of the receptor for ligand B is modified to the same degree. When this occurs, the observed affinity of the ligand A for the receptor will depend on both the concentration of the co-binding allosteric ligand and its nature. The relationships between drug potency in pharmacological models and the equilibrium dissociation constants defined in single mass action reactions are discussed. More detailed knowledge of efficacy has led to new models of drug action that depend on the relative probabilities of different states, and these have taken knowledge of drug-receptor interactions beyond Guldberg and Waage.
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Affiliation(s)
- Terry Kenakin
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, NC, USA
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15
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Biased signalling: the instinctive skill of the cell in the selection of appropriate signalling pathways. Biochem J 2015; 470:155-67. [DOI: 10.1042/bj20150358] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
GPCRs (G-protein-coupled receptors) are members of a family of proteins which are generally regarded as the largest group of therapeutic drug targets. Ligands of GPCRs do not usually activate all cellular signalling pathways linked to a particular seven-transmembrane receptor in a uniform manner. The fundamental idea behind this concept is that each ligand has its own ability, while interacting with the receptor, to activate different signalling pathways (or a particular set of signalling pathways) and it is this concept which is known as biased signalling. The importance of biased signalling is that it may selectively activate biological responses to favour therapeutically beneficial signalling pathways and to avoid adverse effects. There are two levels of biased signalling. First, bias can arise from the ability of GPCRs to couple to a subset of the available G-protein subtypes: Gαs, Gαq/11, Gαi/o or Gα12/13. These subtypes produce the diverse effects of GPCRs by targeting different effectors. Secondly, biased GPCRs may differentially activate G-proteins or β-arrestins. β-Arrestins are ubiquitously expressed and function to terminate or inhibit classic G-protein signalling and initiate distinct β-arrestin-mediated signalling processes. The interplay of G-protein and β-arrestin signalling largely determines the cellular consequences of the administration of GPCR-targeted drugs. In the present review, we highlight the particular functionalities of biased signalling and discuss its biological effects subsequent to GPCR activation. We consider that biased signalling is potentially allowing a choice between signalling through ‘beneficial’ pathways and the avoidance of ‘harmful’ ones.
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16
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Kenakin T. The Effective Application of Biased Signaling to New Drug Discovery. Mol Pharmacol 2015; 88:1055-61. [PMID: 26138073 DOI: 10.1124/mol.115.099770] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2015] [Accepted: 07/02/2015] [Indexed: 01/14/2023] Open
Abstract
The ability of agonists to selectively activate some but not all signaling pathways linked to pleiotropically signaling receptors has opened the possibility of obtaining molecules that emphasize beneficial signals, de-emphasize harmful signals, and concomitantly deemphasize harmful signals while blocking the harmful signals produced by endogenous agonists. The detection and quantification of biased effects is straightforward, but two important factors should be considered in the evaluation of biased effects in drug discovery. The first is that efficacy, and not bias, determines whether a given agonist signal will be observed; bias only dictates the relative concentrations at which agonist signals will appear when they do appear. Therefore, a Cartesian coordinate system plotting relative efficacy (on a scale of Log relative Intrinsic Activities) as the ordinates and Log(bias) as the abscissae is proposed as a useful tool in evaluating possible biased molecules for progression in discovery programs. Second, it should be considered that the current scales quantifying bias limit this property to the allosteric vector (ligand/receptor/coupling protein complex) and that whole-cell processing of this signal can completely change measured bias from in vitro predictions.
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Affiliation(s)
- Terry Kenakin
- Department of Pharmacology, School of Medicine, University of North Carolina, Chapel Hill, North Carolina
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17
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van der Westhuizen ET, Valant C, Sexton PM, Christopoulos A. Endogenous Allosteric Modulators of G Protein–Coupled Receptors. J Pharmacol Exp Ther 2015; 353:246-60. [DOI: 10.1124/jpet.114.221606] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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18
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Leonis G, Avramopoulos A, Salmas RE, Durdagi S, Yurtsever M, Papadopoulos MG. Elucidation of Conformational States, Dynamics, and Mechanism of Binding in Human κ-Opioid Receptor Complexes. J Chem Inf Model 2014; 54:2294-308. [DOI: 10.1021/ci5002873] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Georgios Leonis
- Institute
of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation, 48 Vas. Constantinou Avenue, Athens, Attiki 11635, Greece
| | - Aggelos Avramopoulos
- Institute
of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation, 48 Vas. Constantinou Avenue, Athens, Attiki 11635, Greece
| | - Ramin Ekhteiari Salmas
- Department
of Chemistry, Istanbul Technical University, Istanbul, Istanbul 34469, Turkey
| | - Serdar Durdagi
- Department
of Biophysics, School of Medicine, Bahcesehir University, Istanbul, Istanbul 34349, Turkey
| | - Mine Yurtsever
- Department
of Chemistry, Istanbul Technical University, Istanbul, Istanbul 34469, Turkey
| | - Manthos G. Papadopoulos
- Institute
of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation, 48 Vas. Constantinou Avenue, Athens, Attiki 11635, Greece
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19
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What is pharmacological 'affinity'? Relevance to biased agonism and antagonism. Trends Pharmacol Sci 2014; 35:434-41. [PMID: 25042457 DOI: 10.1016/j.tips.2014.06.003] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 06/16/2014] [Accepted: 06/17/2014] [Indexed: 11/22/2022]
Abstract
The differences between affinity measurements made in binding studies and those relevant to receptor function are described. There are theoretical and practical reasons for not utilizing binding data and, in terms of the quantification of signaling bias, it is unnecessary to do so. Finally, the allosteric control of ligand affinity through receptor-signaling protein interaction is discussed within the context of biased antagonism. In this regard, it is shown that both the bias and relative efficacy of a ligand are essential data for fully predicting biased effects in vivo.
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20
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Gee CE, Peterlik D, Neuhäuser C, Bouhelal R, Kaupmann K, Laue G, Uschold-Schmidt N, Feuerbach D, Zimmermann K, Ofner S, Cryan JF, van der Putten H, Fendt M, Vranesic I, Glatthar R, Flor PJ. Blocking metabotropic glutamate receptor subtype 7 (mGlu7) via the Venus flytrap domain (VFTD) inhibits amygdala plasticity, stress, and anxiety-related behavior. J Biol Chem 2014; 289:10975-10987. [PMID: 24596089 DOI: 10.1074/jbc.m113.542654] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The metabotropic glutamate receptor subtype 7 (mGlu7) is an important presynaptic regulator of neurotransmission in the mammalian CNS. mGlu7 function has been linked to autism, drug abuse, anxiety, and depression. Despite this, it has been difficult to develop specific blockers of native mGlu7 signaling in relevant brain areas such as amygdala and limbic cortex. Here, we present the mGlu7-selective antagonist 7-hydroxy-3-(4-iodophenoxy)-4H-chromen-4-one (XAP044), which inhibits lateral amygdala long term potentiation (LTP) in brain slices from wild type mice with a half-maximal blockade at 88 nm. There was no effect of XAP044 on LTP of mGlu7-deficient mice, indicating that this pharmacological effect is mGlu7-dependent. Unexpectedly and in contrast to all previous mGlu7-selective drugs, XAP044 does not act via the seven-transmembrane region but rather via a binding pocket localized in mGlu7's extracellular Venus flytrap domain, a region generally known for orthosteric agonist binding. This was shown by chimeric receptor studies in recombinant cell line assays. XAP044 demonstrates good brain exposure and wide spectrum anti-stress and antidepressant- and anxiolytic-like efficacy in rodent behavioral paradigms. XAP044 reduces freezing during acquisition of Pavlovian fear and reduces innate anxiety, which is consistent with the phenotypes of mGlu7-deficient mice, the results of mGlu7 siRNA knockdown studies, and the inhibition of amygdala LTP by XAP044. Thus, we present an mGlu7 antagonist with a novel molecular mode of pharmacological action, providing significant application potential in psychiatry. Modeling the selective interaction between XAP044 and mGlu7's Venus flytrap domain, whose three-dimensional structure is already known, will facilitate future drug development supported by computer-assisted drug design.
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Affiliation(s)
- Christine E Gee
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland,; Center for Molecular Neurobiology Hamburg, University Medical Center Hamburg-Eppendorf, D-20249 Hamburg, Germany
| | - Daniel Peterlik
- Faculty of Biology and Preclinical Medicine, Laboratory of Molecular and Cellular Neurobiology, University of Regensburg, D-93053 Regensburg, Germany
| | - Christoph Neuhäuser
- Faculty of Biology and Preclinical Medicine, Laboratory of Molecular and Cellular Neurobiology, University of Regensburg, D-93053 Regensburg, Germany
| | - Rochdi Bouhelal
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland
| | - Klemens Kaupmann
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland
| | - Grit Laue
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland
| | - Nicole Uschold-Schmidt
- Faculty of Biology and Preclinical Medicine, Laboratory of Molecular and Cellular Neurobiology, University of Regensburg, D-93053 Regensburg, Germany
| | - Dominik Feuerbach
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland
| | - Kaspar Zimmermann
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland
| | - Silvio Ofner
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland
| | - John F Cryan
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland,; Department of Anatomy and Neuroscience, University of Cork, Cork, Ireland, and
| | - Herman van der Putten
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland
| | - Markus Fendt
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland,; Institute of Pharmacology and Toxicology and Center of Behavioral Brain Sciences, University of Magdeburg, D-39120 Magdeburg, Germany
| | - Ivo Vranesic
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland
| | - Ralf Glatthar
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland,.
| | - Peter J Flor
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland,; Faculty of Biology and Preclinical Medicine, Laboratory of Molecular and Cellular Neurobiology, University of Regensburg, D-93053 Regensburg, Germany,.
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Abstract
It is now established that agonists do not uniformly activate pleiotropic signaling mechanisms initiated by receptors but rather can bias signals according to the unique receptor conformations they stabilize. One of the important emerging signaling systems where this can occur is through β-arrestin. This chapter discusses biased signaling where emphasis or de-emphasis of β-arrestin signaling is postulated (or been shown) to be beneficial. The chapter specifically focuses on methods to quantify biased effects; these methods furnish scales that can be used in the process of optimizing biased agonism (and antagonism) for therapeutic benefit. Specifically, methods to derive ΔΔLog(τ/K A) or ΔΔLog(Relative Activity) values are described to do this.
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Affiliation(s)
- Terry Kenakin
- Department of Pharmacology, University of North Carolina School of Medicine, 120 Mason Farm Road, Room 4042, Genetic Medicine Building, CB# 7365, Chapel Hill, NC, 27599-7365, USA,
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White KL, Scopton AP, Rives ML, Bikbulatov RV, Polepally PR, Brown PJ, Kenakin T, Javitch JA, Zjawiony JK, Roth BL. Identification of novel functionally selective κ-opioid receptor scaffolds. Mol Pharmacol 2014; 85:83-90. [PMID: 24113749 PMCID: PMC3868907 DOI: 10.1124/mol.113.089649] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 10/10/2013] [Indexed: 11/22/2022] Open
Abstract
The κ-opioid receptor (KOR)-dynorphin system has been implicated in the control of affect, cognition, and motivation, and is thought to be dysregulated in mood and psychotic disorders, as well as in various phases of opioid dependence. KOR agonists exhibit analgesic effects, although the adverse effects produced by some KOR agonists, including sedation, dysphoria, and hallucinations, have limited their clinical use. Interestingly, KOR-mediated dysphoria, assessed in rodents as aversion, has recently been attributed to the activation of the p38 mitogen-activated protein kinase pathway following arrestin recruitment to the activated KOR. Therefore, KOR-selective G protein-biased agonists, which do not recruit arrestin, have been proposed to be more effective analgesics, without the adverse effects triggered by the arrestin pathway. As an initial step toward identifying novel biased KOR agonists, we applied a multifaceted screening strategy utilizing both in silico and parallel screening approaches. We identified several KOR-selective ligand scaffolds with a range of signaling bias in vitro. The arylacetamide-based scaffold includes both G protein- and β-arrestin-biased ligands, while the endogenous peptides and the diterpene scaffolds are G protein biased. Interestingly, we found scaffold screening to be more successful than library screening in identifying biased ligands. Many of the identified functionally selective ligands are potent selective KOR agonists that are reported to be active in the central nervous system. They therefore represent excellent candidates for in vivo studies aiming at determining the behavioral effects mediated by specific KOR-mediated signaling cascades.
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Affiliation(s)
- Kate L White
- Department of Pharmacology (K.L.W., T.K., B.L.R.) and National Institute of Mental Health Psychoactive Drug Screening Program (B.L.R.), University of North Carolina, Chapel Hill, North Carolina; Departments of Psychiatry (M.-L.R, J.A.J.) and Pharmacology (J.A.J.), Columbia University, College of Physicians and Surgeons, New York, New York; New York Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, New York (M.-L.R., J.A.J.); Department of Pharmacognosy, University of Mississippi, University, Mississippi (R.V.B., P.R.P., J.K.Z.); and Structural Genomics Consortium, University of Toronto, Toronto, Ontario, Canada (A.P.S., P.J.B.)
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Nickolls SA, Humphreys S, Clark M, McMurray G. Co-expression of GRK2 reveals a novel conformational state of the µ-opioid receptor. PLoS One 2013; 8:e83691. [PMID: 24376730 PMCID: PMC3869807 DOI: 10.1371/journal.pone.0083691] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Accepted: 11/15/2013] [Indexed: 11/19/2022] Open
Abstract
Agonists at the µ-opioid receptor are known to produce potent analgesic responses in the clinical setting, therefore, an increased understanding of the molecular interactions of ligands at this receptor could lead to improved analgesics. As historically morphine has been shown to be a poor recruiter of β-arrestin in recombinant cell systems and this can be overcome by the co-expression of GRK2, we investigated the effects of GRK2 co-expression, in a recombinant µ-opioid receptor cell line, on ligand affinity and intrinsic activity in both β-arrestin recruitment and [(35)S]GTPγS binding assays. We also investigated the effect of receptor depletion in the β-arrestin assay. GRK2 co-expression increased both agonist Emax and potency in the β-arrestin assay. The increase in agonist potency could not be reversed using receptor depletion, supporting that the effects were due to a novel receptor conformation not system amplification. We also observed a small but significant effect on agonist KL values. Potency values in the [(35)S]GTPγS assay were unchanged; however, inverse agonist activity became evident with GRK2 co-expression. We conclude that this is direct evidence that the µ-opioid receptor is an allosteric protein and the co-expression of signalling molecules elicits changes in its conformation and thus ligand affinity. This has implications when describing how ligands interact with the receptor and how efficacy is determined.
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Affiliation(s)
- Sarah A. Nickolls
- Neusentis, A Pfizer Research Unit, Granta Park, Cambridge, United Kingdom
- * E-mail:
| | - Sian Humphreys
- Neusentis, A Pfizer Research Unit, Granta Park, Cambridge, United Kingdom
| | - Mellissa Clark
- Neusentis, A Pfizer Research Unit, Granta Park, Cambridge, United Kingdom
| | - Gordon McMurray
- Neusentis, A Pfizer Research Unit, Granta Park, Cambridge, United Kingdom
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24
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How ligands and signalling proteins affect G-protein-coupled receptors' conformational landscape. Biochem Soc Trans 2013; 41:144-7. [PMID: 23356274 DOI: 10.1042/bst20120267] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The dynamic character of GPCRs (G-protein-coupled receptors) is essential to their function. However, the details of how ligands and signalling proteins stabilize a receptor conformation to trigger the activation of a given signalling pathway remain largely unexplored. Multiple data, including recent results obtained with the purified ghrelin receptor, suggest a model where ligand efficacy and functional selectivity are directly related to different receptor conformations. Importantly, distinct effector proteins (G-proteins and arrestins) as well as ligands are likely to affect the conformational landscape of GPCRs in different manners, as we show with the isolated ghrelin receptor. Such modulation of the GPCR conformational landscape by pharmacologically distinct ligands and effector proteins has major implications for the design of new drugs that activate specific signalling pathways.
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25
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Kenakin T, Christopoulos A. Measurements of ligand bias and functional affinity. Nat Rev Drug Discov 2013; 12:483. [PMID: 23681003 DOI: 10.1038/nrd3954-c2] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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26
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Kenakin T. New concepts in pharmacological efficacy at 7TM receptors: IUPHAR review 2. Br J Pharmacol 2013; 168:554-75. [PMID: 22994528 PMCID: PMC3579279 DOI: 10.1111/j.1476-5381.2012.02223.x] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Revised: 08/03/2012] [Accepted: 09/12/2012] [Indexed: 01/14/2023] Open
Abstract
The present-day concept of drug efficacy has changed completely from its original description as the property of agonists that causes tissue activation. The ability to visualize the multiple behaviours of seven transmembrane receptors has shown that drugs can have many efficacies and also that the transduction of drug stimulus to various cellular stimulus-response cascades can be biased towards some but not all pathways. This latter effect leads to agonist 'functional selectivity', which can be favourable for the improvement of agonist therapeutics. However, in addition, biased agonist potency becomes cell type dependent with the loss of the monotonic behaviour of stimulus-response mechanisms, leading to potential problems in agonist quantification. This has an extremely important effect on the discovery process for new agonists since it now cannot be assumed that a given screening or lead optimization assay will correctly predict therapeutic behaviour. This review discusses these ideas and how new approaches to quantifying agonist effect may be used to circumvent the cell type dependence of agonism. This article, written by a corresponding member of the International Union of Basic and Clinical Pharmacology Committee on Receptor Nomenclature and Drug Classification (NC-IUPHAR), reviews our current understanding of the interaction of ligands with seven transmembrane receptors. Further information on these pharmacological concepts is being incorporated into the IUPHAR/BPS database GuideToPharmacology.org.
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Affiliation(s)
- Terry Kenakin
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, NC, USA.
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27
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28
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Kenakin T. The potential for selective pharmacological therapies through biased receptor signaling. BMC Pharmacol Toxicol 2012; 13:3. [PMID: 22947056 PMCID: PMC3506267 DOI: 10.1186/2050-6511-13-3] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Accepted: 08/13/2012] [Indexed: 11/10/2022] Open
Abstract
The discovery that not all agonists uniformly activate cellular signaling pathways (biased signaling) has greatly changed the drug discovery process for agonists and the strategy for treatment of disease with agonists. Technological advances have enabled complex receptor behaviors to be viewed independently and through these assays, the bias for an agonist can be quantified. It is predicted that therapeutic phenotypes will be linked, through translational studies, to quantified scales of bias to guide medicinal chemists in the drug discovery process.
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Affiliation(s)
- Terry Kenakin
- Department of Pharmacology, University of North Carolina School of Medicine, 120 Mason Farm Road, Room 4042 Genetic Medicine Building, CB# 7365, Chapel Hill, NC 27599-7365, USA.
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29
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Kabli N, Martin N, Fan T, Nguyen T, Hasbi A, Balboni G, O'Dowd BF, George SR. Agonists at the δ-opioid receptor modify the binding of µ-receptor agonists to the µ-δ receptor hetero-oligomer. Br J Pharmacol 2011; 161:1122-36. [PMID: 20977461 DOI: 10.1111/j.1476-5381.2010.00944.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND AND PURPOSE µ- and δ-opioid receptors form heteromeric complexes with unique ligand binding and G protein-coupling profiles linked to G protein α z-subunit (Gα(z) ) activation. However, the mechanism of action of agonists and their regulation of the µ-δ receptor heteromer are not well understood. EXPERIMENTAL APPROACH Competition radioligand binding, cell surface receptor internalization in intact cells, confocal microscopy and receptor immunofluorescence techniques were employed to study the regulation of the µ-δ receptor heteromer in heterologous cells with and without agonist exposure. KEY RESULTS Gα(z) enhanced affinity of some agonists at µ-δ receptor heteromers, independent of agonist chemical structure. δ-Opioid agonists displaced µ-agonist binding with high affinity from µ-δ heteromers, but not µ receptor homomers, suggestive of δ-agonists occupying a novel µ-receptor ligand binding pocket within the heteromers. Also, δ-agonists induced internalization of µ-opioid receptors in cells co-expressing µ- and δ-receptors, but not those expressing µ-receptors alone, indicative of µ-δ heteromer internalization. This dose-dependent, Pertussis toxin-resistant and clathrin- and dynamin-dependent effect required agonist occupancy of both µ- and δ-opioid receptors. In contrast to µ-receptor homomers, agonist-induced internalization of µ-δ heteromers persisted following chronic morphine exposure. CONCLUSIONS AND IMPLICATIONS The µ-δ receptor heteromer may contain a novel δ-agonist-detected, high-affinity, µ-receptor ligand binding pocket and is regulated differently from the µ-receptor homomer following chronic morphine exposure. Occupancy of both µ- and δ-receptor binding pockets is required for δ-agonist-induced endocytosis of µ-δ receptor heteromers. δ-Opioid agonists target µ-δ receptor heteromers, and thus have a broader pharmacological specificity than previously identified.
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Affiliation(s)
- N Kabli
- Centre for Addiction and Mental Health, Toronto, Ontario, Canada
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30
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McGovern DL, Mosier PD, Roth BL, Westkaemper RB. CoMFA analyses of C-2 position salvinorin A analogs at the kappa-opioid receptor provides insights into epimer selectivity. J Mol Graph Model 2010; 28:612-25. [PMID: 20083418 DOI: 10.1016/j.jmgm.2009.12.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2009] [Revised: 11/20/2009] [Accepted: 12/21/2009] [Indexed: 12/15/2022]
Abstract
The highly potent and kappa-opioid (KOP) receptor-selective hallucinogen Salvinorin A and selected analogs have been analyzed using the 3D quantitative structure-affinity relationship technique Comparative Molecular Field Analysis (CoMFA) in an effort to derive a statistically significant and predictive model of salvinorin affinity at the KOP receptor and to provide additional statistical support for the validity of previously proposed structure-based interaction models. Two CoMFA models of Salvinorin A analogs substituted at the C-2 position are presented. Separate models were developed based on the radioligand used in the kappa-opioid binding assay, [(3)H]diprenorphine or [(125)I]6 beta-iodo-3,14-dihydroxy-17-cyclopropylmethyl-4,5 alpha-epoxymorphinan ([(125)I]IOXY). For each dataset, three methods of alignment were employed: a receptor-docked alignment derived from the structure-based docking algorithm GOLD, another from the ligand-based alignment algorithm FlexS, and a rigid realignment of the poses from the receptor-docked alignment. The receptor-docked alignment produced statistically superior results compared to either the FlexS alignment or the realignment in both datasets. The [(125)I]IOXY set (Model 1) and [(3)H]diprenorphine set (Model 2) gave q(2) values of 0.592 and 0.620, respectively, using the receptor-docked alignment, and both models produced similar CoMFA contour maps that reflected the stereoelectronic features of the receptor model from which they were derived. Each model gave significantly predictive CoMFA statistics (Model 1 PSET r(2)=0.833; Model 2 PSET r(2)=0.813). Based on the CoMFA contour maps, a binding mode was proposed for amine-containing Salvinorin A analogs that provides a rationale for the observation that the beta-epimers (R-configuration) of protonated amines at the C-2 position have a higher affinity than the corresponding alpha-epimers (S-configuration).
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Affiliation(s)
- Donna L McGovern
- Department of Medicinal Chemistry, P.O. Box 980540, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298-0540, USA
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31
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Abstract
This paper is the 31st consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2008 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurologic disorders (Section 11); electrical-related activity and neurophysiology (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration and thermoregulation (Section 16); and immunological responses (Section 17).
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, 65-30 Kissena Blvd, Flushing, NY 11367, United States.
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32
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Hudson BD, Hébert TE, M. Kelly ME. Ligand- and Heterodimer-Directed Signaling of the CB1 Cannabinoid Receptor. Mol Pharmacol 2009; 77:1-9. [DOI: 10.1124/mol.109.060251] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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Yan F, Bikbulatov RV, Mocanu V, Dicheva N, Parker CE, Wetsel WC, Mosier PD, Westkaemper RB, Allen JA, Zjawiony JK, Roth BL. Structure-based design, synthesis, and biochemical and pharmacological characterization of novel salvinorin A analogues as active state probes of the kappa-opioid receptor. Biochemistry 2009; 48:6898-908. [PMID: 19555087 DOI: 10.1021/bi900605n] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Salvinorin A, the most potent naturally occurring hallucinogen, has attracted an increasing amount of attention since the kappa-opioid receptor (KOR) was identified as its principal molecular target by us [Roth, B. L., et al. (2002) Proc. Natl. Acad. Sci. U.S.A. 99, 11934-11939]. Here we report the design, synthesis, and biochemical characterization of novel, irreversible, salvinorin A-derived ligands suitable as active state probes of the KOR. On the basis of prior substituted cysteine accessibility and molecular modeling studies, C315(7.38) was chosen as a potential anchoring point for covalent labeling of salvinorin A-derived ligands. Automated docking of a series of potential covalently bound ligands suggested that either a haloacetate moiety or other similar electrophilic groups could irreversibly bind with C315(7.38). 22-Thiocyanatosalvinorin A (RB-64) and 22-chlorosalvinorin A (RB-48) were both found to be extraordinarily potent and selective KOR agonists in vitro and in vivo. As predicted on the basis of molecular modeling studies, RB-64 induced wash-resistant inhibition of binding with a strict requirement for a free cysteine in or near the binding pocket. Mass spectrometry (MS) studies utilizing synthetic KOR peptides and RB-64 supported the hypothesis that the anchoring residue was C315(7.38) and suggested one biochemical mechanism for covalent binding. These studies provide direct evidence of the presence of a free cysteine in the agonist-bound state of the KOR and provide novel insights into the mechanism by which salvinorin A binds to and activates the KOR.
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Affiliation(s)
- Feng Yan
- Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina 27599, USA
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34
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Li G, Mosier PD, Fang X, Zhang Y. Toward the three-dimensional structure and lysophosphatidic acid binding characteristics of the LPA(4)/p2y(9)/GPR23 receptor: a homology modeling study. J Mol Graph Model 2009; 28:70-9. [PMID: 19423373 DOI: 10.1016/j.jmgm.2009.04.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Revised: 03/24/2009] [Accepted: 04/11/2009] [Indexed: 11/16/2022]
Abstract
Lysophosphatidic acid (LPA) is a naturally occurring phospholipid that initiates a broad array of biological processes, including those involved in cell proliferation, survival and migration via activation of specific G protein-coupled receptors located on the cell surface. To date, at least five receptor subtypes (LPA(1-5)) have been identified. The LPA(1-3) receptors are members of the endothelial cell differentiation gene (Edg) family. LPA(4), a member of the purinergic receptor family, and the recently identified LPA(5) are structurally distant from the canonical Edg LPA(1-3) receptors. LPA(4) and LPA(5) are linked to G(q), G(12/13) and G(s) but not G(i), while LPA(1-3) all couple to G(i) in addition to G(q) and G(12/13). There is also evidence that LPA(4) and LPA(5) are functionally different from the Edg LPA receptors. Computational modeling has provided useful information on the structure-activity relationship (SAR) of the Edg LPA receptors. In this work, we focus on the initial analysis of the structural and ligand-binding properties of LPA(4), a prototype non-Edg LPA receptor. Three homology models of the LPA(4) receptor were developed based on the X-ray crystal structures of the ground state and photoactivated bovine rhodopsin and the recently determined human beta(2)-adrenergic receptor. Docking studies of LPA in the homology models were then conducted, and plausible LPA binding loci were explored. Based on these analyses, LPA is predicted to bind to LPA(4) in an orientation similar to that reported for LPA(1-3), but through a different network of hydrogen bonds. In LPA(1-3), the ligand polar head group is reported to interact with residues at positions 3.28, 3.29 and 7.36, whereas three non-conserved amino acid residues, S114(3.28), T187(EL2) and Y265(6.51), are predicted to interact with the polar head group in the LPA(4) receptor models.
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Affiliation(s)
- Guo Li
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298-0540, USA
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35
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Pei Y, Rogan SC, Yan F, Roth BL. Engineered GPCRs as tools to modulate signal transduction. Physiology (Bethesda) 2009; 23:313-21. [PMID: 19074739 DOI: 10.1152/physiol.00025.2008] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Different families of G-protein-coupled receptors (GPCRs) have been engineered to provide exclusive control over the activation of these receptors and thus to understand better the consequences of their signaling in vitro and in vivo. These engineered receptors, named RASSLs (receptors activated solely by synthetic ligands) and DREADDs (designer receptors exclusively activated by designer drugs), are insensitive to their endogenous ligands but can be activated by synthetic drug-like compounds. Currently, the existing RASSLs and DREADDs cover the Gi, Gq, and Gs signaling pathways. These modified GPCRs can be utilized as ideal tools to study GPCR functions selectively in specific cellular populations.
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Affiliation(s)
- Ying Pei
- Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina, USA
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36
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Jastrzebska B, Golczak M, Fotiadis D, Engel A, Palczewski K. Isolation and functional characterization of a stable complex between photoactivated rhodopsin and the G protein, transducin. FASEB J 2008; 23:371-81. [PMID: 18827025 DOI: 10.1096/fj.07-114835] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Transitory binding between photoactivated rhodopsin (Rho* or Meta II) and the G protein transducin (Gt-GDP) is the first step in the visual signaling cascade. Light causes photoisomerization of the 11-cis-retinylidene chromophore in rhodopsin (Rho) to all-trans-retinylidene, which induces conformational changes that allow Gt-GDP to dock onto the Rho* surface. GDP then dissociates from Gt, leaving a transient nucleotide-empty Rho*-Gt(e) complex before GTP becomes bound, and Gt-GTP then dissociates from Rho*. Further biochemical advances are required before structural studies of the various Rho*-Gt complexes can be initiated. Here, we describe the isolation of n-dodecyl-beta-maltoside solubilized, stable, functionally active, Rho*-Gt(e), Rho(e)*-Gt(e), and 9-cis-retinal/11-cis-retinal regenerated Rho-Gt(e) complexes by sucrose gradient centrifugation. In these complexes, Rho* spectrally remained in its Meta II state, and Gt(e) retained its ability to interact with GTPgammaS. Removal of all-trans-retinylidene from Rho*-Gt(e) had no effect on the stability of the Rho(e)*-Gt(e) complex. Moreover, opsin in the Rho(e)*-Gt(e) complex with an empty nucleotide-binding pocket in Gt and an empty retinoid-binding pocket in Rho was regenerated up to 75% without complex dissociation. These results indicate that once Rho* couples with Gt, the chromophore plays a minor role in stabilizing this complex. Moreover, in complexes regenerated with 9-cis-retinal/11-cis-retinal, Rho retains a conformation similar to Rho* that is stabilized by Gt(e) apo-protein.
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Affiliation(s)
- Beata Jastrzebska
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Wood Bldg., 10900 Euclid Ave., Cleveland, OH 44106-4965, USA.
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Cozzini P, Kellogg GE, Spyrakis F, Abraham DJ, Costantino G, Emerson A, Fanelli F, Gohlke H, Kuhn LA, Morris GM, Orozco M, Pertinhez TA, Rizzi M, Sotriffer CA. Target flexibility: an emerging consideration in drug discovery and design. J Med Chem 2008; 51:6237-55. [PMID: 18785728 DOI: 10.1021/jm800562d] [Citation(s) in RCA: 206] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Pietro Cozzini
- Department of General and Inorganic Chemistry, University of Parma, Via G.P. Usberti 17/A 43100, Parma,
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