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Hovah ME, Holzgrabe U. Bivalent and bitopic ligands of the opioid receptors: The prospects of a dual approach. Med Res Rev 2024; 44:2545-2599. [PMID: 38751227 DOI: 10.1002/med.22050] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 04/09/2024] [Accepted: 05/05/2024] [Indexed: 10/05/2024]
Abstract
Opioid receptors belonging to the class A G-protein coupled receptors (GPCRs) are the targets of choice in the treatment of acute and chronic pain. However, their on-target side effects such as respiratory depression, tolerance and addiction have led to the advent of the 'opioid crisis'. In the search for safer analgesics, bivalent and more recently, bitopic ligands have emerged as valuable tool compounds to probe these receptors. The activity of bivalent and bitopic ligands rely greatly on the allosteric nature of the GPCRs. Bivalent ligands consist of two pharmacophores, each binding to the individual orthosteric binding site (OBS) of the monomers within a dimer. Bitopic or dualsteric ligands bridge the gap between the OBS and the spatially distinct, less conserved allosteric binding site (ABS) through the simultaneous occupation of these two sites. Bivalent and bitopic ligands stabilize distinct conformations of the receptors which ultimately translates into unique signalling and pharmacological profiles. Some of the interesting properties shown by these ligands include improved affinity and/or efficacy, subtype and/or functional selectivity and reduced side effects. This review aims at providing an overview of some of the bivalent and bitopic ligands of the opioid receptors and, their pharmacology in the hope of inspiring the design and discovery of the next generation of opioid analgesics.
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Affiliation(s)
- Marie Emilie Hovah
- Institute of Pharmacy and Food Chemistry, University of Wuerzburg, Am Hubland, Wuerzburg, Germany
| | - Ulrike Holzgrabe
- Institute of Pharmacy and Food Chemistry, University of Wuerzburg, Am Hubland, Wuerzburg, Germany
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2
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Yu C, Richly M, Hoang TT, El Beheiry M, Türkcan S, Masson JB, Alexandrou A, Bouzigues CI. Confinement energy landscape classification reveals membrane receptor nano-organization mechanisms. Biophys J 2024; 123:1882-1895. [PMID: 38845200 PMCID: PMC11267427 DOI: 10.1016/j.bpj.2024.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 03/01/2024] [Accepted: 06/03/2024] [Indexed: 06/22/2024] Open
Abstract
The cell membrane organization has an essential functional role through the control of membrane receptor confinement in micro- or nanodomains. Several mechanisms have been proposed to account for these properties, although some features have remained controversial, notably the nature, size, and stability of cholesterol- and sphingolipid-rich domains or lipid rafts. Here, we probed the effective energy landscape acting on single-nanoparticle-labeled membrane receptors confined in raft nanodomains- epidermal growth factor receptor (EGFR), Clostridium perfringens ε-toxin receptor (CPεTR), and Clostridium septicum α-toxin receptor (CSαTR)-and compared it with hop-diffusing transferrin receptors. By establishing a new analysis pipeline combining Bayesian inference, decision trees, and clustering approaches, we systematically classified single-protein trajectories according to the type of effective confining energy landscape. This revealed the existence of only two distinct organization modalities: confinement in a quadratic energy landscape for EGFR, CPεTR, and CSαTR (A), and free diffusion in confinement domains resulting from the steric hindrance due to F-actin barriers for transferrin receptor (B). The further characterization of effective confinement energy landscapes by Bayesian inference revealed the role of interactions with the domain environment in cholesterol- and sphingolipid-rich domains with (EGFR) or without (CPεTR and CSαTR) interactions with F-actin to regulate the confinement energy depth. These two distinct mechanisms result in the same organization type (A). We revealed that the apparent domain sizes for these receptor trajectories resulted from Brownian exploration of the energy landscape in a steady-state-like regime at a common effective temperature, independently of the underlying molecular mechanisms. These results highlight that confinement domains may be adequately described as interaction hotspots rather than rafts with abrupt domain boundaries. Altogether, these results support a new model for functional receptor confinement in membrane nanodomains and pave the way to the constitution of an atlas of membrane protein organization.
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Affiliation(s)
- Chao Yu
- Laboratoire Optique et Biosciences, CNRS UMR74645, Inserm U1182, Ecole Polytechnique, Institut Polytechnique Paris, Palaiseau, France
| | - Maximilian Richly
- Laboratoire Optique et Biosciences, CNRS UMR74645, Inserm U1182, Ecole Polytechnique, Institut Polytechnique Paris, Palaiseau, France
| | - Thi Thuy Hoang
- Laboratoire Optique et Biosciences, CNRS UMR74645, Inserm U1182, Ecole Polytechnique, Institut Polytechnique Paris, Palaiseau, France
| | - Mohammed El Beheiry
- Institut Pasteur, Université Paris Cité, CNRS UMR 3571, Decision and Bayesian Computation, Paris, France; Épiméthée, INRIA, Paris, France
| | - Silvan Türkcan
- Laboratoire Optique et Biosciences, CNRS UMR74645, Inserm U1182, Ecole Polytechnique, Institut Polytechnique Paris, Palaiseau, France
| | - Jean-Baptiste Masson
- Institut Pasteur, Université Paris Cité, CNRS UMR 3571, Decision and Bayesian Computation, Paris, France; Épiméthée, INRIA, Paris, France
| | - Antigoni Alexandrou
- Laboratoire Optique et Biosciences, CNRS UMR74645, Inserm U1182, Ecole Polytechnique, Institut Polytechnique Paris, Palaiseau, France
| | - Cedric I Bouzigues
- Laboratoire Optique et Biosciences, CNRS UMR74645, Inserm U1182, Ecole Polytechnique, Institut Polytechnique Paris, Palaiseau, France.
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3
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Nehr-Majoros AK, Király Á, Helyes Z, Szőke É. Lipid raft disruption as an opportunity for peripheral analgesia. Curr Opin Pharmacol 2024; 75:102432. [PMID: 38290404 DOI: 10.1016/j.coph.2024.102432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 12/17/2023] [Accepted: 01/02/2024] [Indexed: 02/01/2024]
Abstract
Chronic pain conditions are unmet medical needs, since the available drugs, opioids, non-steroidal anti-inflammatory/analgesic drugs and adjuvant analgesics do not provide satisfactory therapeutic effect in a great proportion of patients. Therefore, there is an urgent need to find novel targets and novel therapeutic approaches that differ from classical pharmacological receptor antagonism. Most ion channels and receptors involved in pain sensation and processing such as Transient Receptor Potential ion channels, opioid receptors, P2X purinoreceptors and neurokinin 1 receptor are located in the lipid raft regions of the plasma membrane. Targeting the membrane lipid composition and structure by sphingolipid or cholesterol depletion might open future perspectives for the therapy of chronic inflammatory, neuropathic or cancer pain, most importantly acting at the periphery.
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Affiliation(s)
- Andrea Kinga Nehr-Majoros
- Department of Pharmacology and Pharmacotherapy, Medical School & Centre for Neuroscience, University of Pécs, 12 Szigeti Street, H-7624, Pécs, Hungary; National Laboratory for Drug Research and Development, Budapest, Hungary; Hungarian Research Network, Chronic Pain Research Group, Pécs, Hungary
| | - Ágnes Király
- Department of Pharmacology and Pharmacotherapy, Medical School & Centre for Neuroscience, University of Pécs, 12 Szigeti Street, H-7624, Pécs, Hungary; National Laboratory for Drug Research and Development, Budapest, Hungary; Hungarian Research Network, Chronic Pain Research Group, Pécs, Hungary
| | - Zsuzsanna Helyes
- Department of Pharmacology and Pharmacotherapy, Medical School & Centre for Neuroscience, University of Pécs, 12 Szigeti Street, H-7624, Pécs, Hungary; National Laboratory for Drug Research and Development, Budapest, Hungary; Hungarian Research Network, Chronic Pain Research Group, Pécs, Hungary
| | - Éva Szőke
- Department of Pharmacology and Pharmacotherapy, Medical School & Centre for Neuroscience, University of Pécs, 12 Szigeti Street, H-7624, Pécs, Hungary; National Laboratory for Drug Research and Development, Budapest, Hungary; Hungarian Research Network, Chronic Pain Research Group, Pécs, Hungary.
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4
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Li Z, Liu J, Dong F, Chang N, Huang R, Xia M, Patterson TA, Hong H. Three-Dimensional Structural Insights Have Revealed the Distinct Binding Interactions of Agonists, Partial Agonists, and Antagonists with the µ Opioid Receptor. Int J Mol Sci 2023; 24:ijms24087042. [PMID: 37108204 PMCID: PMC10138646 DOI: 10.3390/ijms24087042] [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: 03/14/2023] [Revised: 04/09/2023] [Accepted: 04/09/2023] [Indexed: 04/29/2023] Open
Abstract
The United States is experiencing the most profound and devastating opioid crisis in history, with the number of deaths involving opioids, including prescription and illegal opioids, continuing to climb over the past two decades. This severe public health issue is difficult to combat as opioids remain a crucial treatment for pain, and at the same time, they are also highly addictive. Opioids act on the opioid receptor, which in turn activates its downstream signaling pathway that eventually leads to an analgesic effect. Among the four types of opioid receptors, the µ subtype is primarily responsible for the analgesic cascade. This review describes available 3D structures of the µ opioid receptor in the protein data bank and provides structural insights for the binding of agonists and antagonists to the receptor. Comparative analysis on the atomic details of the binding site in these structures was conducted and distinct binding interactions for agonists, partial agonists, and antagonists were observed. The findings in this article deepen our understanding of the ligand binding activity and shed some light on the development of novel opioid analgesics which may improve the risk benefit balance of existing opioids.
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Affiliation(s)
- Zoe Li
- National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA
| | - Jie Liu
- National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA
| | - Fan Dong
- National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA
| | - Nancy Chang
- Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD 20903, USA
| | - Ruili Huang
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20892, USA
| | - Menghang Xia
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tucker A Patterson
- National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA
| | - Huixiao Hong
- National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA
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Shpakov AO. Allosteric Regulation of G-Protein-Coupled Receptors: From Diversity of Molecular Mechanisms to Multiple Allosteric Sites and Their Ligands. Int J Mol Sci 2023; 24:6187. [PMID: 37047169 PMCID: PMC10094638 DOI: 10.3390/ijms24076187] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/21/2023] [Accepted: 03/23/2023] [Indexed: 03/29/2023] Open
Abstract
Allosteric regulation is critical for the functioning of G protein-coupled receptors (GPCRs) and their signaling pathways. Endogenous allosteric regulators of GPCRs are simple ions, various biomolecules, and protein components of GPCR signaling (G proteins and β-arrestins). The stability and functional activity of GPCR complexes is also due to multicenter allosteric interactions between protomers. The complexity of allosteric effects caused by numerous regulators differing in structure, availability, and mechanisms of action predetermines the multiplicity and different topology of allosteric sites in GPCRs. These sites can be localized in extracellular loops; inside the transmembrane tunnel and in its upper and lower vestibules; in cytoplasmic loops; and on the outer, membrane-contacting surface of the transmembrane domain. They are involved in the regulation of basal and orthosteric agonist-stimulated receptor activity, biased agonism, GPCR-complex formation, and endocytosis. They are targets for a large number of synthetic allosteric regulators and modulators, including those constructed using molecular docking. The review is devoted to the principles and mechanisms of GPCRs allosteric regulation, the multiplicity of allosteric sites and their topology, and the endogenous and synthetic allosteric regulators, including autoantibodies and pepducins. The allosteric regulation of chemokine receptors, proteinase-activated receptors, thyroid-stimulating and luteinizing hormone receptors, and beta-adrenergic receptors are described in more detail.
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Affiliation(s)
- Alexander O Shpakov
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, 194223 St. Petersburg, Russia
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6
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Marlow B, Kuenze G, Meiler J, Koehler Leman J. Docking cholesterol to integral membrane proteins with Rosetta. PLoS Comput Biol 2023; 19:e1010947. [PMID: 36972273 PMCID: PMC10042369 DOI: 10.1371/journal.pcbi.1010947] [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: 11/04/2022] [Accepted: 02/14/2023] [Indexed: 03/29/2023] Open
Abstract
Lipid molecules such as cholesterol interact with the surface of integral membrane proteins (IMP) in a mode different from drug-like molecules in a protein binding pocket. These differences are due to the lipid molecule's shape, the membrane's hydrophobic environment, and the lipid's orientation in the membrane. We can use the recent increase in experimental structures in complex with cholesterol to understand protein-cholesterol interactions. We developed the RosettaCholesterol protocol consisting of (1) a prediction phase using an energy grid to sample and score native-like binding poses and (2) a specificity filter to calculate the likelihood that a cholesterol interaction site may be specific. We used a multi-pronged benchmark (self-dock, flip-dock, cross-dock, and global-dock) of protein-cholesterol complexes to validate our method. RosettaCholesterol improved sampling and scoring of native poses over the standard RosettaLigand baseline method in 91% of cases and performs better regardless of benchmark complexity. On the β2AR, our method found one likely-specific site, which is described in the literature. The RosettaCholesterol protocol quantifies cholesterol binding site specificity. Our approach provides a starting point for high-throughput modeling and prediction of cholesterol binding sites for further experimental validation.
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Affiliation(s)
- Brennica Marlow
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, United States of America
- Chemical and Physical Biology Program, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Georg Kuenze
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, United States of America
- Institute for Drug Discovery, Leipzig University Medical School, Leipzig, Germany
| | - Jens Meiler
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, United States of America
- Chemical and Physical Biology Program, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, United States of America
- Institute for Drug Discovery, Leipzig University Medical School, Leipzig, Germany
| | - Julia Koehler Leman
- Center for Computational Biology, Flatiron Institute, Simons Foundation, New York, New York, United States of America
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7
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Chronis IB, Puthenveedu MA. Patching holes in the mechanism of opioid tolerance. Trends Pharmacol Sci 2023; 44:70-72. [PMID: 36435677 PMCID: PMC10320836 DOI: 10.1016/j.tips.2022.11.005] [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: 11/05/2022] [Revised: 11/16/2022] [Accepted: 11/17/2022] [Indexed: 11/27/2022]
Abstract
Tolerance is a significant obstacle to use of opioids as safe pain relieving drugs, but the cellular processes that result in tolerance have remained elusive. A new study by Maza and colleagues identifies the protein Patched domain-containing 1 (PTCHD1) and its effects on cellular cholesterol as potential targets for preventing opioid tolerance.
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Affiliation(s)
- Ian B Chronis
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48109, USA.
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8
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Opioid-Modulated Receptor Localization and Erk1/2 Phosphorylation in Cells Coexpressing μ-Opioid and Nociceptin Receptors. Int J Mol Sci 2023; 24:ijms24021048. [PMID: 36674576 PMCID: PMC9865058 DOI: 10.3390/ijms24021048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 12/30/2022] [Accepted: 01/03/2023] [Indexed: 01/09/2023] Open
Abstract
We attempted to examine the alterations elicited by opioids via coexpressed μ-opioid (MOP) and nociceptin/orphanin FQ (NOP) receptors for receptor localization and Erk1/2 (p44/42 MAPK) in human embryonic kidney (HEK) 293 cells. Through two-photon microscopy, the proximity of MOP and NOP receptors was verified by fluorescence resonance energy transfer (FRET), and morphine but not buprenorphine facilitated the process of MOP-NOP heterodimerization. Single-particle tracking (SPT) further revealed that morphine or buprenorphine hindered the movement of the MOP-NOP heterodimers. After exposure to morphine or buprenorphine, receptor localization on lipid rafts was detected by immunocytochemistry, and phosphorylation of Erk1/2 was determined by immunoblotting in HEK 293 cells expressing MOP, NOP, or MOP+NOP receptors. Colocalization of MOP and NOP on lipid rafts was enhanced by morphine but not buprenorphine. Morphine stimulated the phosphorylation of Erk1/2 with a similar potency in HEK 293 cells expressing MOP and MOP+NOP receptors, but buprenorphine appeared to activate Erk1/2 solely through NOP receptors. Our results suggest that opioids can fine-tune the cellular localization of opioid receptors and phosphorylation of Erk1/2 in MOP+NOP-expressing cells.
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9
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Calderon-Garcia AA, Perez-Fernandez M, Curto-Aguilera D, Rodriguez-Martin I, Sánchez-Barba M, Gonzalez-Nunez V. Exposure to Morphine and Cocaine Modify the Transcriptomic Landscape in Zebrafish Embryos. Neuroscience 2022; 507:14-27. [PMID: 36404518 DOI: 10.1016/j.neuroscience.2022.10.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 10/17/2022] [Accepted: 10/20/2022] [Indexed: 11/19/2022]
Abstract
Morphine and other opioid analgesics are the drugs of election to treat moderate-to-severe pain, and they elicit their actions by binding to the opioid receptors. Cocaine is a potent inhibitor of dopamine, serotonin, and noradrenaline reuptake, as it blocks DAT, the dopamine transporter, causing an increase in the local concentration of these neurotransmitters in the synaptic cleft. The molecular effects of these drugs have been studied in specific brain areas or nuclei, but the systemic effects in the whole organism have not been comprehensively analyzed. This study aims to analyze the transcriptomic changes elicited by morphine (10 uM) and cocaine (15 uM) in zebrafish embryos. An RNAseq assay was performed with tissues extracts from zebrafish embryos treated from 5 hpf (hours post fertilization) to 72 hpf, and the most representative deregulated genes were experimentally validated by qPCR. We have found changes in the expression of genes related to lipid metabolism, chemokine receptor ligands, visual system, hemoglobins, and metabolic detoxification pathways. Besides, morphine and cocaine modified the global DNA methylation pattern in zebrafish embryos, which would explain the changes in gene expression elicited by these two drugs of abuse.
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Affiliation(s)
- Andrés Angel Calderon-Garcia
- Dept. Biochemistry and Molecular Biology, Faculty of Medicine, University of Salamanca, Spain; Instituto de Neurociencias de Castilla y León (INCYL), Faculty of Medicine, University of Salamanca, Spain; Institute of Biomedical Research of Salamanca (IBSAL), Spain
| | - Maria Perez-Fernandez
- Instituto de Neurociencias de Castilla y León (INCYL), Faculty of Medicine, University of Salamanca, Spain
| | - Daniel Curto-Aguilera
- Dept. Biochemistry and Molecular Biology, Faculty of Medicine, University of Salamanca, Spain
| | - Ivan Rodriguez-Martin
- Faculty of Experimental Sciences, Universidad Francisco de Vitoria, Pozuelo de Alarcón, Madrid, Spain
| | - Mercedes Sánchez-Barba
- Institute of Biomedical Research of Salamanca (IBSAL), Spain; Dept. Statistics. Faculty of Medicine, University of Salamanca, Spain
| | - Veronica Gonzalez-Nunez
- Dept. Biochemistry and Molecular Biology, Faculty of Medicine, University of Salamanca, Spain; Instituto de Neurociencias de Castilla y León (INCYL), Faculty of Medicine, University of Salamanca, Spain; Institute of Biomedical Research of Salamanca (IBSAL), Spain.
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10
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Bean BDM, Mulvihill CJ, Garge RK, Boutz DR, Rousseau O, Floyd BM, Cheney W, Gardner EC, Ellington AD, Marcotte EM, Gollihar JD, Whiteway M, Martin VJJ. Functional expression of opioid receptors and other human GPCRs in yeast engineered to produce human sterols. Nat Commun 2022; 13:2882. [PMID: 35610225 PMCID: PMC9130329 DOI: 10.1038/s41467-022-30570-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 05/09/2022] [Indexed: 12/12/2022] Open
Abstract
The yeast Saccharomyces cerevisiae is powerful for studying human G protein-coupled receptors as they can be coupled to its mating pathway. However, some receptors, including the mu opioid receptor, are non-functional, which may be due to the presence of the fungal sterol ergosterol instead of cholesterol. Here we engineer yeast to produce cholesterol and introduce diverse mu, delta, and kappa opioid receptors to create sensitive opioid biosensors that recapitulate agonist binding profiles and antagonist inhibition. Additionally, human mu opioid receptor variants, including those with clinical relevance, largely display expected phenotypes. By testing mu opioid receptor-based biosensors with systematically adjusted cholesterol biosynthetic intermediates, we relate sterol profiles to biosensor sensitivity. Finally, we apply sterol-modified backgrounds to other human receptors revealing sterol influence in SSTR5, 5-HTR4, FPR1, and NPY1R signaling. This work provides a platform for generating human G protein-coupled receptor-based biosensors, facilitating receptor deorphanization and high-throughput screening of receptors and effectors.
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Affiliation(s)
- Björn D M Bean
- Department of Biology, Centre for Applied Synthetic Biology, Concordia University, Montréal, QC, H4B1R6, Canada
| | - Colleen J Mulvihill
- Department of Molecular Biosciences, Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Riddhiman K Garge
- Department of Molecular Biosciences, Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Daniel R Boutz
- Department of Molecular Biosciences, Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, TX, 78712, USA
- DEVCOM Army Research Laboratory-South, Austin, 78712, TX, USA
| | - Olivier Rousseau
- Department of Biology, Centre for Applied Synthetic Biology, Concordia University, Montréal, QC, H4B1R6, Canada
| | - Brendan M Floyd
- Department of Molecular Biosciences, Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, TX, 78712, USA
| | - William Cheney
- Department of Biology, Centre for Applied Synthetic Biology, Concordia University, Montréal, QC, H4B1R6, Canada
| | - Elizabeth C Gardner
- Department of Molecular Biosciences, Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Andrew D Ellington
- Department of Molecular Biosciences, Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Edward M Marcotte
- Department of Molecular Biosciences, Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Jimmy D Gollihar
- Department of Molecular Biosciences, Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, TX, 78712, USA.
- DEVCOM Army Research Laboratory-South, Austin, 78712, TX, USA.
- Center for Molecular and Translational Human Infectious Diseases Research, Department of Pathology and Genomic Medicine, Houston Methodist Research Institute, Houston Methodist Hospital, Houston, TX, USA.
| | - Malcolm Whiteway
- Department of Biology, Centre for Applied Synthetic Biology, Concordia University, Montréal, QC, H4B1R6, Canada
| | - Vincent J J Martin
- Department of Biology, Centre for Applied Synthetic Biology, Concordia University, Montréal, QC, H4B1R6, Canada.
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11
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Jakubík J, El-Fakahany EE. Allosteric Modulation of GPCRs of Class A by Cholesterol. Int J Mol Sci 2021; 22:1953. [PMID: 33669406 PMCID: PMC7920425 DOI: 10.3390/ijms22041953] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 02/11/2021] [Accepted: 02/12/2021] [Indexed: 12/16/2022] Open
Abstract
G-protein coupled receptors (GPCRs) are membrane proteins that convey extracellular signals to the cellular milieu. They represent a target for more than 30% of currently marketed drugs. Here we review the effects of membrane cholesterol on the function of GPCRs of Class A. We review both the specific effects of cholesterol mediated via its direct high-affinity binding to the receptor and non-specific effects mediated by cholesterol-induced changes in the properties of the membrane. Cholesterol binds to many GPCRs at both canonical and non-canonical binding sites. It allosterically affects ligand binding to and activation of GPCRs. Additionally, it changes the oligomerization state of GPCRs. In this review, we consider a perspective of the potential for the development of new therapies that are targeted at manipulating the level of membrane cholesterol or modulating cholesterol binding sites on to GPCRs.
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Affiliation(s)
- Jan Jakubík
- Department of Neurochemistry, Institute of Physiology Czech Academy of Sciences, 142 20 Prague, Czech Republic
| | - Esam E. El-Fakahany
- Department of Experimental and Clinical Pharmacology, University of Minnesota College of Pharmacy, Minneapolis, MN 55455, USA
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12
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Interaction of drugs with lipid raft membrane domains as a possible target. Drug Target Insights 2021; 14:34-47. [PMID: 33510571 PMCID: PMC7832984 DOI: 10.33393/dti.2020.2185] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 11/11/2020] [Indexed: 01/23/2023] Open
Abstract
Introduction Plasma membranes are not the homogeneous bilayers of uniformly distributed lipids but the lipid complex with laterally separated lipid raft membrane domains, which provide receptor, ion channel and enzyme proteins with a platform. The aim of this article is to review the mechanistic interaction of drugs with membrane lipid rafts and address the question whether drugs induce physicochemical changes in raft-constituting and raft-surrounding membranes. Methods Literature searches of PubMed/MEDLINE and Google Scholar databases from 2000 to 2020 were conducted to include articles published in English in internationally recognized journals. Collected articles were independently reviewed by title, abstract and text for relevance. Results The literature search indicated that pharmacologically diverse drugs interact with raft model membranes and cellular membrane lipid rafts. They could physicochemically modify functional protein-localizing membrane lipid rafts and the membranes surrounding such domains, affecting the raft organizational integrity with the resultant exhibition of pharmacological activity. Raft-acting drugs were characterized as ones to decrease membrane fluidity, induce liquid-ordered phase or order plasma membranes, leading to lipid raft formation; and ones to increase membrane fluidity, induce liquid-disordered phase or reduce phase transition temperature, leading to lipid raft disruption. Conclusion Targeting lipid raft membrane domains would open a new way for drug design and development. Since angiotensin-converting enzyme 2 receptors which are a cell-specific target of and responsible for the cellular entry of novel coronavirus are localized in lipid rafts, agents that specifically disrupt the relevant rafts may be a drug against coronavirus disease 2019.
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13
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Crilly SE, Puthenveedu MA. Compartmentalized GPCR Signaling from Intracellular Membranes. J Membr Biol 2020; 254:259-271. [PMID: 33231722 DOI: 10.1007/s00232-020-00158-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 11/11/2020] [Indexed: 12/21/2022]
Abstract
G protein-coupled receptors (GPCRs) are integral membrane proteins that transduce a wide array of inputs including light, ions, hormones, and neurotransmitters into intracellular signaling responses which underlie complex processes ranging from vision to learning and memory. Although traditionally thought to signal primarily from the cell surface, GPCRs are increasingly being recognized as capable of signaling from intracellular membrane compartments, including endosomes, the Golgi apparatus, and nuclear membranes. Remarkably, GPCR signaling from these membranes produces functional effects that are distinct from signaling from the plasma membrane, even though often the same G protein effectors and second messengers are activated. In this review, we will discuss the emerging idea of a "spatial bias" in signaling. We will present the evidence for GPCR signaling through G protein effectors from intracellular membranes, and the ways in which this signaling differs from canonical plasma membrane signaling with important implications for physiology and pharmacology. We also highlight the potential mechanisms underlying spatial bias of GPCR signaling, including how intracellular membranes and their associated lipids and proteins affect GPCR activity and signaling.
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Affiliation(s)
- Stephanie E Crilly
- Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, MI, 48109, USA.
| | - Manojkumar A Puthenveedu
- Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, MI, 48109, USA.,Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
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14
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Agonist binding of human mu opioid receptors expressed in the yeast Pichia pastoris: Effect of cholesterol complementation. Neurochem Int 2019; 132:104588. [PMID: 31704091 DOI: 10.1016/j.neuint.2019.104588] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 09/26/2019] [Accepted: 11/04/2019] [Indexed: 01/14/2023]
Abstract
This study compared pharmacological profiles between human mu opioid receptors (hMOR) overexpressed in the SH-SY5Y neuroblastoma cell line (SH-hMOR) and the methylotrophic yeast Pichia pastoris (Pp-hMOR). Affinity determinations were performed by direct binding with the tritiated agonist DAMGO and antagonist diprenorphine (DIP). Additionally, displacement of these drugs with agonists (morphine and DAMGO) and antagonists (β-funaltrexamine, naloxone and diprenorphine) was examined. Tritiated DAMGO could bind to membranes prepared from Pp-hMOR, although the receptor was not coupled with G-proteins. The data obtained with this yeast strain suggested that only 7.5% of receptors were in a high-affinity-state conformation. This value was markedly less than that estimated in SH-hMOR membranes, which reached 50%. Finally, to understand the pharmacological discrepancies between Pp-hMOR and SH-hMOR, the role of sterols was evaluated. The major sterol in P. pastoris is ergosterol, while hMOR naturally functions in a cholesterol-containing membrane environment. Cell membranes were sterol-depleted or cholesterol-loaded with methyl-β-cyclodextrine. The results indicated that cholesterol must be present to ensure Pp-hMOR function. The proportion of high-affinity-state conformation was reversibly increased by cholesterol complementation.
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15
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Startek JB, Boonen B, López-Requena A, Talavera A, Alpizar YA, Ghosh D, Van Ranst N, Nilius B, Voets T, Talavera K. Mouse TRPA1 function and membrane localization are modulated by direct interactions with cholesterol. eLife 2019; 8:e46084. [PMID: 31184584 PMCID: PMC6590989 DOI: 10.7554/elife.46084] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 06/10/2019] [Indexed: 01/04/2023] Open
Abstract
The cation channel TRPA1 transduces a myriad of noxious chemical stimuli into nociceptor electrical excitation and neuropeptide release, leading to pain and neurogenic inflammation. Despite emergent evidence that TRPA1 is regulated by the membrane environment, it remains unknown whether this channel localizes in membrane microdomains or whether it interacts with cholesterol. Using total internal reflection fluorescence microscopy and density gradient centrifugation we found that mouse TRPA1 localizes preferably into cholesterol-rich domains and functional experiments revealed that cholesterol depletion decreases channel sensitivity to chemical agonists. Moreover, we identified two structural motifs in transmembrane segments 2 and 4 involved in mTRPA1-cholesterol interactions that are necessary for normal agonist sensitivity and plasma membrane localization. We discuss the impact of such interactions on TRPA1 gating mechanisms, regulation by the lipid environment, and role of this channel in sensory membrane microdomains, all of which helps to understand the puzzling pharmacology and pathophysiology of this channel.
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Affiliation(s)
- Justyna B Startek
- Laboratory of Ion Channel Research and TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular MedicineKU LeuvenLeuvenBelgium
- VIB Center for Brain & Disease ResearchLeuvenBelgium
| | - Brett Boonen
- Laboratory of Ion Channel Research and TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular MedicineKU LeuvenLeuvenBelgium
- VIB Center for Brain & Disease ResearchLeuvenBelgium
| | - Alejandro López-Requena
- Laboratory of Ion Channel Research and TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular MedicineKU LeuvenLeuvenBelgium
- VIB Center for Brain & Disease ResearchLeuvenBelgium
| | - Ariel Talavera
- Center for Microscopy and Molecular Imaging (CMMI), Laboratory of MicroscopyUniversité Libre de BruxellesGosseliesBelgium
| | - Yeranddy A Alpizar
- Laboratory of Ion Channel Research and TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular MedicineKU LeuvenLeuvenBelgium
- VIB Center for Brain & Disease ResearchLeuvenBelgium
| | - Debapriya Ghosh
- Laboratory of Ion Channel Research and TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular MedicineKU LeuvenLeuvenBelgium
- VIB Center for Brain & Disease ResearchLeuvenBelgium
| | - Nele Van Ranst
- Laboratory of Ion Channel Research and TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular MedicineKU LeuvenLeuvenBelgium
- VIB Center for Brain & Disease ResearchLeuvenBelgium
| | - Bernd Nilius
- Laboratory of Ion Channel Research and TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular MedicineKU LeuvenLeuvenBelgium
- VIB Center for Brain & Disease ResearchLeuvenBelgium
| | - Thomas Voets
- Laboratory of Ion Channel Research and TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular MedicineKU LeuvenLeuvenBelgium
- VIB Center for Brain & Disease ResearchLeuvenBelgium
| | - Karel Talavera
- Laboratory of Ion Channel Research and TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular MedicineKU LeuvenLeuvenBelgium
- VIB Center for Brain & Disease ResearchLeuvenBelgium
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16
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Matsuo Y, Suematsu Y, Idemoto Y, Kuwano T, Kitajima K, Miura SI. Changes in the function of angiotensin II type 1 receptor due to cholesterol depletion from cell membrane. Biochem Biophys Res Commun 2019; 514:791-797. [PMID: 31079923 DOI: 10.1016/j.bbrc.2019.05.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Accepted: 05/02/2019] [Indexed: 12/11/2022]
Abstract
Blockers of G-protein coupled receptors (GPCRs), angiotensin II (Ang II) type 1 (AT1) receptor and β1-adrenergic (Ad) receptor, have been shown to improve the prognosis of cardiovascular disease. Cholesterol molecules in the cell membrane are needed to stabilize GPCRs as well as the cell membrane itself. We determined whether the functions of AT1 and β1-Ad receptors were changed by cholesterol depletion from cardiovascular cell membranes. Ang II-induced inositol phosphate production through AT1 receptor was suppressed by cholesterol depletion from cell membranes using rosuvastatin or methyl-β-cyclodextrin (MβCD), whereas isoproterenol-induced cyclic AMP production through β1-Ad receptor did not change after cholesterol depletion. In addition, the binding affinities of Ang II and AT1 receptor blocker after cholesterol depletion were significantly lower than those before depletion. Although AT1 receptor expression levels did not change after cholesterol depletion, the expression levels of AT1 receptor that could bind to Ang II significantly decreased after depletion. The changes in the structure of AT1 receptor due to depletion were confirmed by substituted-cysteine accessibility mapping. In conclusion, Ang II-induced activation of AT1 receptor is reduced without affecting the function of β1-Ad receptor after cholesterol depletion from cardiovascular cell membranes.
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Affiliation(s)
- Yoshino Matsuo
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Yasunori Suematsu
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Yoshiaki Idemoto
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Takashi Kuwano
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Ken Kitajima
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Shin-Ichiro Miura
- Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Japan.
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17
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Huang L, Wyse BD, Williams CM, Smith MT. Nitric oxide modulates μ-opioid receptor function in vitro. Clin Exp Pharmacol Physiol 2019; 46:676-685. [PMID: 30933370 DOI: 10.1111/1440-1681.13091] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 03/02/2019] [Accepted: 03/27/2019] [Indexed: 01/10/2023]
Abstract
Painful diabetic neuropathy (PDN) is a type of peripheral neuropathic pain that develops as a consequence of prolonged hyperglycaemia-induced injury to the long nerves. Apart from pain, PDN is also characterized by morphine hyposensitivity. Intriguingly, in streptozotocin (STZ)-induced diabetic rats exhibiting marked morphine hyposensitivity, dietary administration of the nitric oxide (NO) precursor, L-arginine at 1 g/d, progressively rescued morphine efficacy and potency over an 8-week treatment period. In earlier work, single bolus doses of the furoxan nitric oxide (NO) donor, PRG150 (3-methylfuroxan-4-carbaldehyde), evoked dose-dependent pain relief in STZ-diabetic rats but the efficacious doses were 3-4 orders of magnitude higher in advanced diabetes than that required in early STZ diabetes. Together, these findings suggested a role for NO in the modulation of μ-opioid (MOP) receptor signalling. Therefore, the present study was designed to assess a role for NO released from PRG150, in modulating MOP receptor function in vitro. Here, we show an absolute requirement for the MOP receptor, but not the δ-opioid (DOP) or the κ-opioid (KOP) receptor, to transduce the cellular effects of PRG150 on forskolin-stimulated cAMP responses in vitro. PRG150 did not interact with the classical naloxone-sensitive binding site of the MOP receptor, and its effects on cAMP responses in HEK-MOP cells were also naloxone-insensitive. Nevertheless, the inhibitory effects of PRG150 on forskolin-stimulated cAMP responses in HEK-MOP cells were dependent upon pertussis toxin (PTX)-sensitive Gi/o proteins as well as membrane lipid rafts and src kinase. Together, our findings implicate a role for NO in modulating MOP receptor function in vivo.
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Affiliation(s)
- Lillian Huang
- School of Pharmacy, Faculty of Health and Behavioural Sciences, The University of Queensland, Brisbane, Queensland, Australia.,School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, Brisbane, Queensland, Australia
| | - Bruce D Wyse
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, Brisbane, Queensland, Australia
| | - Craig M Williams
- School of Chemistry and Molecular Biosciences, Faculty of Science, The University of Queensland, Brisbane, Queensland, Australia
| | - Maree T Smith
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, Brisbane, Queensland, Australia
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18
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A Critical Analysis of Molecular Mechanisms Underlying Membrane Cholesterol Sensitivity of GPCRs. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1115:21-52. [PMID: 30649754 DOI: 10.1007/978-3-030-04278-3_2] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
G protein-coupled receptors (GPCRs) are the largest and a diverse family of proteins involved in signal transduction across biological membranes. GPCRs mediate a wide range of physiological processes and have emerged as major targets for the development of novel drug candidates in all clinical areas. Since GPCRs are integral membrane proteins, regulation of their organization, dynamics, and function by membrane lipids, in particular membrane cholesterol, has emerged as an exciting area of research. Cholesterol sensitivity of GPCRs could be due to direct interaction of cholesterol with the receptor (specific effect). Alternately, GPCR function could be influenced by the effect of cholesterol on membrane physical properties (general effect). In this review, we critically analyze the specific and general mechanisms of the modulation of GPCR function by membrane cholesterol, taking examples from representative GPCRs. While evidence for both the proposed mechanisms exists, there appears to be no clear-cut distinction between these two mechanisms, and a combination of these mechanisms cannot be ruled out in many cases. We conclude that classifying the mechanism underlying cholesterol sensitivity of GPCR function merely into these two mutually exclusive classes could be somewhat arbitrary. A more holistic approach could be suitable for analyzing GPCR-cholesterol interaction.
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19
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Randáková A, Dolejší E, Rudajev V, Zimčík P, Doležal V, El-Fakahany EE, Jakubík J. Role of membrane cholesterol in differential sensitivity of muscarinic receptor subtypes to persistently bound xanomeline. Neuropharmacology 2018; 133:129-144. [PMID: 29407765 DOI: 10.1016/j.neuropharm.2018.01.027] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 01/03/2018] [Accepted: 01/21/2018] [Indexed: 01/24/2023]
Abstract
Xanomeline (3-(Hexyloxy)-4-(1-methyl-1,2,5,6-tetrahydropyridin-3-yl)-1,2,5-thiadiazole) is a muscarinic agonist that is considered to be functionally selective for the M1/M4 receptor subtypes. Part of xanomeline binding is resistant to washing. Wash-resistant xanomeline activates muscarinic receptors persistently, except for the M5 subtype. Mutation of leucine 6.46 to isoleucine at M1 or M4 receptors abolished persistent activation by wash-resistant xanomeline. Reciprocal mutation of isoleucine 6.46 to leucine at the M5 receptor made it sensitive to activation by wash-resistant xanomeline. Lowering of membrane cholesterol made M1 and M4 mutants and M5 wild type receptors sensitive to activation by wash-resistant xanomeline. Molecular docking revealed a cholesterol binding site in the groove between transmembrane helices 6 and 7. Molecular dynamics showed that interaction of cholesterol with this binding site attenuates receptor activation. We hypothesize that differences in cholesterol binding to this site between muscarinic receptor subtypes may constitute the basis for xanomeline apparent functional selectivity and may have notable therapeutic implications. Differences in receptor-membrane interactions, rather than in agonist-receptor interactions, represent a novel possibility to achieve pharmacological selectivity. Our findings may be applicable to other G protein coupled receptors.
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Affiliation(s)
- Alena Randáková
- Institute of Physiology Czech Academy of Sciences, 142 20 Prague, Czech Republic
| | - Eva Dolejší
- Institute of Physiology Czech Academy of Sciences, 142 20 Prague, Czech Republic
| | - Vladimír Rudajev
- Institute of Physiology Czech Academy of Sciences, 142 20 Prague, Czech Republic
| | - Pavel Zimčík
- Institute of Physiology Czech Academy of Sciences, 142 20 Prague, Czech Republic
| | - Vladimír Doležal
- Institute of Physiology Czech Academy of Sciences, 142 20 Prague, Czech Republic
| | - Esam E El-Fakahany
- Department of Experimental and Clinical Pharmacology, University of Minnesota College of Pharmacy, Minneapolis, MN 55455, USA
| | - Jan Jakubík
- Institute of Physiology Czech Academy of Sciences, 142 20 Prague, Czech Republic.
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20
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Livingston KE, Traynor JR. Allostery at opioid receptors: modulation with small molecule ligands. Br J Pharmacol 2018; 175:2846-2856. [PMID: 28419415 PMCID: PMC6016636 DOI: 10.1111/bph.13823] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 03/31/2017] [Accepted: 04/04/2017] [Indexed: 12/14/2022] Open
Abstract
Opioid receptors are 7-transmembrane domain receptors that couple to heterotrimeric G proteins. The endogenous ligands for opioid receptors are peptides which bind to the orthosteric site on the receptors. The μ-opioid receptor is the target for opioid analgesics, while the δ-opioid receptor has been suggested as a target for pain management, migraine and depression. Similarly, κ-opioid receptors are involved in pain and depression and nociceptin receptors in pain and mood behaviours. However, exogenous orthosteric ligands for opioid receptors cause a myriad of on-target side effects. Recently, selective allosteric ligands for μ- and δ-opioid receptors have been described. These compounds bind to a site on the receptor distinct from the orthosteric site. Occupation of this allosteric site leads to modulation of orthosteric ligand binding affinity and/or efficacy. Allosteric modulators may be positive, negative or silent (neutral) (PAMs, NAMs or SAMs respectively). PAMs may have in vivo activity by enhancing the activity of exogenous drugs or endogenous opioid peptides. Enhancing endogenous opioid peptide activity maintains the temporal and spatial distribution of these molecules but improves, and potentially qualitatively changes, activity at their cognate receptors which could limit side effects compared with traditional opioid drugs. In this review, we describe the rationale and promise for the development of allosteric modulators for opioid receptors, the discovery of selective allosteric modulators, the identification of potential allosteric sites on opioid receptors and the mode of action of the modulators. 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)
| | - John R Traynor
- Department of PharmacologyUniversity of Michigan Medical SchoolAnn ArborMIUSA
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21
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Rogacki MK, Golfetto O, Tobin SJ, Li T, Biswas S, Jorand R, Zhang H, Radoi V, Ming Y, Svenningsson P, Ganjali D, Wakefield DL, Sideris A, Small AR, Terenius L, Jovanović‐Talisman T, Vukojević V. Dynamic lateral organization of opioid receptors (kappa, mu wt and mu N40D ) in the plasma membrane at the nanoscale level. Traffic 2018; 19:690-709. [PMID: 29808515 PMCID: PMC6120469 DOI: 10.1111/tra.12582] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 05/06/2018] [Accepted: 05/18/2018] [Indexed: 02/06/2023]
Abstract
Opioid receptors are important pharmacological targets for the management of numerous medical conditions (eg, severe pain), but they are also the gateway to the development of deleterious side effects (eg, opiate addiction). Opioid receptor signaling cascades are well characterized. However, quantitative information regarding their lateral dynamics and nanoscale organization in the plasma membrane remains limited. Since these dynamic properties are important determinants of receptor function, it is crucial to define them. Herein, the nanoscale lateral dynamics and spatial organization of kappa opioid receptor (KOP), wild type mu opioid receptor (MOPwt ), and its naturally occurring isoform (MOPN40D ) were quantitatively characterized using fluorescence correlation spectroscopy and photoactivated localization microscopy. Obtained results, supported by ensemble-averaged Monte Carlo simulations, indicate that these opioid receptors dynamically partition into different domains. In particular, significant exclusion from GM1 ganglioside-enriched domains and partial association with cholesterol-enriched domains was observed. Nanodomain size, receptor population density and the fraction of receptors residing outside of nanodomains were receptor-specific. KOP-containing domains were the largest and most densely populated, with the smallest fraction of molecules residing outside of nanodomains. The opposite was true for MOPN40D . Moreover, cholesterol depletion dynamically regulated the partitioning of KOP and MOPwt , whereas this effect was not observed for MOPN40D .
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Affiliation(s)
- Maciej K. Rogacki
- Department of Clinical NeuroscienceCenter for Molecular Medicine, Karolinska InstituteStockholmSweden
| | - Ottavia Golfetto
- Department of Molecular Medicine, Beckman Research Institute, City of HopeDuarteCalifornia
| | - Steven J. Tobin
- Department of Molecular Medicine, Beckman Research Institute, City of HopeDuarteCalifornia
| | - Tianyi Li
- Department of Clinical NeuroscienceCenter for Molecular Medicine, Karolinska InstituteStockholmSweden
| | - Sunetra Biswas
- Department of Molecular Medicine, Beckman Research Institute, City of HopeDuarteCalifornia
| | - Raphael Jorand
- Department of Molecular Medicine, Beckman Research Institute, City of HopeDuarteCalifornia
| | - Huiying Zhang
- Department of Molecular Medicine, Beckman Research Institute, City of HopeDuarteCalifornia
| | - Vlad Radoi
- Department of Clinical NeuroscienceCenter for Molecular Medicine, Karolinska InstituteStockholmSweden
| | - Yu Ming
- Department of Clinical NeuroscienceCenter for Molecular Medicine, Karolinska InstituteStockholmSweden
| | - Per Svenningsson
- Department of Clinical NeuroscienceCenter for Molecular Medicine, Karolinska InstituteStockholmSweden
| | - Daniel Ganjali
- Department of Mechanical and Aerospace EngineeringThe Henry Samueli School of Engineering, University of CaliforniaIrvineCalifornia
| | - Devin L. Wakefield
- Department of Molecular Medicine, Beckman Research Institute, City of HopeDuarteCalifornia
| | - Athanasios Sideris
- Department of Mechanical and Aerospace EngineeringThe Henry Samueli School of Engineering, University of CaliforniaIrvineCalifornia
| | - Alexander R. Small
- Department of Physics and AstronomyCalifornia State Polytechnic UniversityPomonaCalifornia
| | - Lars Terenius
- Department of Clinical NeuroscienceCenter for Molecular Medicine, Karolinska InstituteStockholmSweden
- Department of Molecular and Cellular NeurosciencesThe Scripps Research InstituteLa JollaCalifornia
| | | | - Vladana Vukojević
- Department of Clinical NeuroscienceCenter for Molecular Medicine, Karolinska InstituteStockholmSweden
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22
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Abstract
The opioid receptor family, with associated endogenous ligands, has numerous roles throughout the body. Moreover, the delta opioid receptor (DORs) has various integrated roles within the physiological systems, including the cardiovascular system. While DORs are important modulators of cardiovascular autonomic balance, they are well-established contributors to cardioprotective mechanisms. Both endogenous and exogenous opioids acting upon DORs have roles in myocardial hibernation and protection against ischaemia-reperfusion (I-R) injury. Downstream signalling mechanisms governing protective responses alternate, depending on the timing and duration of DOR activation. The following review describes models and mechanisms of DOR-mediated cardioprotection, the impact of co-morbidities and challenges for clinical translation.
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Affiliation(s)
- Louise See Hoe
- Menzies Health Institute Queensland, Griffith University, Southport, QLD, 4222, Australia
- Critical Care Research Group, The Prince Charles Hospital and The University of Queensland, Chermside, QLD, Australia
| | - Hemal H Patel
- VA San Diego Healthcare System, San Diego, CA, USA
- Department of Anesthesiology, University of California San Diego, La Jolla, CA, USA
| | - Jason N Peart
- Menzies Health Institute Queensland, Griffith University, Southport, QLD, 4222, Australia.
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23
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Accessibility of axonal G protein coupled mu-opioid receptors requires conceptual changes of axonal membrane targeting for pain modulation. J Control Release 2017; 268:352-363. [PMID: 29054370 DOI: 10.1016/j.jconrel.2017.10.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 10/07/2017] [Accepted: 10/13/2017] [Indexed: 12/19/2022]
Abstract
The mechanisms of axonal trafficking and membrane targeting are well established for sodium channels, which are the principle targets for perineurally applied local anaesthetics. However, they have not been thoroughly investigated for G protein coupled receptors such as mu-opioid receptors (MOR). Focusing on these axonal mechanisms, we found that axonal MOR functionality is quite distinct in two different pain states, i.e. hindpaw inflammation and nerve injury. We observed axonal membrane MOR binding and functional G protein coupling exclusively at sites of CCI nerve injury. Moreover at these axonal membrane sites, MOR exhibited extensive co-localization with the membrane proteins SNAP and Na/K-ATPase as well as NGF-dependent enhanced lipid rafts and L1CAM anchoring proteins. Silencing endogenous L1CAM with intrathecal L1CAM specific siRNA, disrupting lipid rafts with the perineurial cholesterol-sequestering agent MβCD, as well as suppressing NGF receptor activation with the perineurial NGF receptor inhibitor K252a abrogated MOR axonal membrane integration, functional coupling, and agonist-elicited antinociception at sites of nerve injury. These findings suggest that local conceptual changes resulting from nerve injury are required for the establishment of functional axonal membrane MOR. Axonal integration and subsequent accessibility of functionally coupled MOR are of great relevance particularly for patients suffering from severe pain due to nerve injury or tumour infiltration.
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24
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Bodzon-Kulakowska A, Antolak A, Drabik A, Marszalek-Grabska M, Kotlińska J, Suder P. Brain lipidomic changes after morphine, cocaine and amphetamine administration — DESI — MS imaging study. Biochim Biophys Acta Mol Cell Biol Lipids 2017; 1862:686-691. [DOI: 10.1016/j.bbalip.2017.04.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 04/11/2017] [Accepted: 04/12/2017] [Indexed: 12/28/2022]
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25
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Gendron L, Cahill CM, von Zastrow M, Schiller PW, Pineyro G. Molecular Pharmacology of δ-Opioid Receptors. Pharmacol Rev 2017; 68:631-700. [PMID: 27343248 DOI: 10.1124/pr.114.008979] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Opioids are among the most effective analgesics available and are the first choice in the treatment of acute severe pain. However, partial efficacy, a tendency to produce tolerance, and a host of ill-tolerated side effects make clinically available opioids less effective in the management of chronic pain syndromes. Given that most therapeutic opioids produce their actions via µ-opioid receptors (MOPrs), other targets are constantly being explored, among which δ-opioid receptors (DOPrs) are being increasingly considered as promising alternatives. This review addresses DOPrs from the perspective of cellular and molecular determinants of their pharmacological diversity. Thus, DOPr ligands are examined in terms of structural and functional variety, DOPrs' capacity to engage a multiplicity of canonical and noncanonical G protein-dependent responses is surveyed, and evidence supporting ligand-specific signaling and regulation is analyzed. Pharmacological DOPr subtypes are examined in light of the ability of DOPr to organize into multimeric arrays and to adopt multiple active conformations as well as differences in ligand kinetics. Current knowledge on DOPr targeting to the membrane is examined as a means of understanding how these receptors are especially active in chronic pain management. Insight into cellular and molecular mechanisms of pharmacological diversity should guide the rational design of more effective, longer-lasting, and better-tolerated opioid analgesics for chronic pain management.
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Affiliation(s)
- Louis Gendron
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Catherine M Cahill
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Mark von Zastrow
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Peter W Schiller
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Graciela Pineyro
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
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Chakrabarti S, Chang A, Liu NJ, Gintzler AR. Chronic opioid treatment augments caveolin-1 scaffolding: relevance to stimulatory μ-opioid receptor adenylyl cyclase signaling. J Neurochem 2016; 139:737-747. [PMID: 27726130 DOI: 10.1111/jnc.13852] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 08/21/2016] [Accepted: 09/15/2016] [Indexed: 01/25/2023]
Abstract
Caveolin-1 is the predominant structural protein of caveolae, a subset of (lipid) membrane rafts that compartmentalize cell signaling. Caveolin-1 binds most to G protein-coupled receptors and their signaling partners, thereby enhancing interactions among signaling cascade components and the relative activation of specific G protein-coupled pathways. This study reveals that chronic opioid exposure of μ-opioid receptor (MOR) expressing Chinese hamster ovary cells (MOR-CHO) and chronic in vivo morphine exposure of rat spinal cord augmented recruitment of multiple components of MOR-adenylyl cyclase (AC) stimulatory signaling by caveolin-1. Strikingly, in MOR-CHO and spinal cord, blocking the caveolin-1 scaffolding domain substantially attenuated the chronic morphine-induced increased interaction of caveolin-1 with MOR, Gsα, protein phosphatase 2A (PP2A), and AC. Chronic morphine treatment also increased interactions among the above signaling proteins, thus enabling sufentanil to stimulate (rather than inhibit) cAMP production within lipid membrane microdomains. The latter finding underscores the functionality of augmented interactions among MOR, Gs α, PP2A, and AC. In the aggregate, our data strongly suggest that augmented caveolin-1 scaffolding undergirds the ability of chronic opioids to recruit an ancillary signaling pathway by acting as an organizing template for MOR-Gs α-AC signaling and delimiting the membrane compartment(s) in which it occurs. Since caveolin-1 binds to a wide spectrum of signaling molecules, altered caveolin-1 scaffolding following chronic opioid treatment is likely to pertain to most, if not all, MOR signaling partners. The chronic morphine-induced trigger that augments caveolin-1 scaffolding could represent a seminal perturbation that initiates the wide spectrum of adaptations thought to contribute to opioid tolerance and dependence.
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Affiliation(s)
- Sumita Chakrabarti
- Department of Obstetrics and Gynecology, State University of New York, Downstate Medical Center, Brooklyn, New York, USA
| | - Andrew Chang
- Department of Obstetrics and Gynecology, State University of New York, Downstate Medical Center, Brooklyn, New York, USA
| | - Nai-Jiang Liu
- Department of Obstetrics and Gynecology, State University of New York, Downstate Medical Center, Brooklyn, New York, USA
| | - Alan R Gintzler
- Department of Obstetrics and Gynecology, State University of New York, Downstate Medical Center, Brooklyn, New York, USA
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27
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Costa-Neto CM, Parreiras-E-Silva LT, Bouvier M. A Pluridimensional View of Biased Agonism. Mol Pharmacol 2016; 90:587-595. [PMID: 27638872 DOI: 10.1124/mol.116.105940] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Accepted: 09/14/2016] [Indexed: 12/17/2022] Open
Abstract
When studying G protein-coupled receptor (GPCR) signaling and ligand-biased agonism, at least three dimensional spaces must be considered, as follows: 1) the distinct conformations that can be stabilized by different ligands promoting the engagement of different signaling effectors and accessory regulators; 2) the distinct subcellular trafficking that can be conferred by different ligands, which results in spatially distinct signals; and 3) the differential binding kinetics that maintain the receptor in specific conformation and/or subcellular localization for different periods of time, allowing for the engagement of distinct signaling effector subsets. These three pluridimensional aspects of signaling contribute to different faces of functional selectivity and provide a complex, interconnected way to define the signaling profile of each individual ligand acting at GPCRs. In this review, we discuss how each of these aspects may contribute to the diversity of signaling, but also how they shed light on the complexity of data analyses and interpretation. The impact of phenotype variability as a source of signaling diversity, and the influence of novel and more sensitive assays in the detection and analysis of signaling pluridimensionality, is also discussed. Finally, we discuss perspectives for the use of the concept of pluridimensional signaling in drug discovery, in which we highlight future predictive tools that may facilitate the identification of compounds with optimal therapeutic and safety properties based on the signaling signatures of drug candidates.
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Affiliation(s)
- Claudio M Costa-Neto
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of São Paulo, Ribeirao Preto, Brazil (C.M.C.-N., L.T.P.-S.); and Department of Biochemistry and Molecular Medicine and Institute for Research in Immunology and Cancer, University of Montréal, Montréal, Canada (L.T.P.-S., M.B.)
| | - Lucas T Parreiras-E-Silva
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of São Paulo, Ribeirao Preto, Brazil (C.M.C.-N., L.T.P.-S.); and Department of Biochemistry and Molecular Medicine and Institute for Research in Immunology and Cancer, University of Montréal, Montréal, Canada (L.T.P.-S., M.B.)
| | - Michel Bouvier
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of São Paulo, Ribeirao Preto, Brazil (C.M.C.-N., L.T.P.-S.); and Department of Biochemistry and Molecular Medicine and Institute for Research in Immunology and Cancer, University of Montréal, Montréal, Canada (L.T.P.-S., M.B.)
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28
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See Hoe LE, May LT, Headrick JP, Peart JN. Sarcolemmal dependence of cardiac protection and stress-resistance: roles in aged or diseased hearts. Br J Pharmacol 2016; 173:2966-91. [PMID: 27439627 DOI: 10.1111/bph.13552] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 06/27/2016] [Accepted: 06/28/2016] [Indexed: 12/25/2022] Open
Abstract
Disruption of the sarcolemmal membrane is a defining feature of oncotic death in cardiac ischaemia-reperfusion (I-R), and its molecular makeup not only fundamentally governs this process but also affects multiple determinants of both myocardial I-R injury and responsiveness to cardioprotective stimuli. Beyond the influences of membrane lipids on the cytoprotective (and death) receptors intimately embedded within this bilayer, myocardial ionic homeostasis, substrate metabolism, intercellular communication and electrical conduction are all sensitive to sarcolemmal makeup, and critical to outcomes from I-R. As will be outlined in this review, these crucial sarcolemmal dependencies may underlie not only the negative effects of age and common co-morbidities on myocardial ischaemic tolerance but also the on-going challenge of implementing efficacious cardioprotection in patients suffering accidental or surgically induced I-R. We review evidence for the involvement of sarcolemmal makeup changes in the impairment of stress-resistance and cardioprotection observed with ageing and highly prevalent co-morbid conditions including diabetes and hypercholesterolaemia. A greater understanding of membrane changes with age/disease, and the inter-dependences of ischaemic tolerance and cardioprotection on sarcolemmal makeup, can facilitate the development of strategies to preserve membrane integrity and cell viability, and advance the challenging goal of implementing efficacious 'cardioprotection' in clinically relevant patient cohorts. Linked Articles This article is part of a themed section on Molecular Pharmacology of G Protein-Coupled Receptors. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v173.20/issuetoc.
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Affiliation(s)
- Louise E See Hoe
- Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia.,Critical Care Research Group, The Prince Charles Hospital and The University of Queensland, Chermside, Queensland, Australia
| | - Lauren T May
- Monash Institute of Pharmaceutical Sciences, Monash University, Clayton, VIC, Australia
| | - John P Headrick
- Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia
| | - Jason N Peart
- Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia.
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29
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Melkes B, Hejnova L, Novotny J. Biased μ-opioid receptor agonists diversely regulate lateral mobility and functional coupling of the receptor to its cognate G proteins. Naunyn Schmiedebergs Arch Pharmacol 2016; 389:1289-1300. [PMID: 27600870 DOI: 10.1007/s00210-016-1293-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 08/24/2016] [Indexed: 12/26/2022]
Abstract
There are some indications that biased μ-opioid ligands may diversely affect μ-opioid receptor (MOR) properties. Here, we used confocal fluorescence recovery after photobleaching (FRAP) to study the regulation by different MOR agonists of receptor movement within the plasma membrane of HEK293 cells stably expressing a functional yellow fluorescent protein (YFP)-tagged μ-opioid receptor (MOR-YFP). We found that the lateral mobility of MOR-YFP was increased by (D-Ala2,N-MePhe4,Gly5-ol)-enkephalin (DAMGO) and to a lesser extent also by morphine but decreased by endomorphin-2. Interestingly, cholesterol depletion strongly enhanced the ability of morphine to elevate receptor mobility but significantly reduced or even eliminated the effect of DAMGO and endomorphin-2, respectively. Moreover, the ability of DAMGO and endomorphin-2 to influence MOR-YFP movement was diminished by pertussis toxin treatment. The results obtained by agonist-stimulated [35S]GTPγS binding assays indicated that DAMGO exhibited higher efficacy than morphine and endomorphin-2 did and that the efficacy of DAMGO, contrary to the latter agonists, was enhanced by cholesterol depletion. Overall, our study provides clear evidence that biased MOR agonists diversely affect receptor mobility in plasma membranes as well as MOR/G protein coupling and that the regulatory effect of different ligands depends on the membrane cholesterol content. These findings help to delineate the fundamental properties of MOR regarding their interaction with biased MOR ligands and cognate G proteins.
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Affiliation(s)
- Barbora Melkes
- Department of Physiology, Faculty of Science, Charles University in Prague, Prague, Czech Republic
| | - Lucie Hejnova
- Department of Physiology, Faculty of Science, Charles University in Prague, Prague, Czech Republic
| | - Jiri Novotny
- Department of Physiology, Faculty of Science, Charles University in Prague, Prague, Czech Republic.
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30
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Huang Z, Liang L, Li L, Xu M, Li X, Sun H, He S, Lin L, Zhang Y, Song Y, Yang M, Luo Y, Loh HH, Law PY, Zheng D, Zheng H. Opioid doses required for pain management in lung cancer patients with different cholesterol levels: negative correlation between opioid doses and cholesterol levels. Lipids Health Dis 2016; 15:47. [PMID: 26952011 PMCID: PMC4782347 DOI: 10.1186/s12944-016-0212-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 02/24/2016] [Indexed: 02/01/2023] Open
Abstract
Background Pain management has been considered as significant contributor to broad quality-of-life improvement for cancer patients. Modulating serum cholesterol levels affects analgesia abilities of opioids, important pain killer for cancer patients, in mice system. Thus the correlation between opioids usages and cholesterol levels were investigated in human patients with lung cancer. Methods Medical records of 282 patients were selected with following criteria, 1) signed inform consent, 2) full medical records on total serum cholesterol levels and opioid administration, 3) opioid-naïve, 4) not received/receiving cancer-related or cholesterol lowering treatment, 5) pain level at level 5–8. The patients were divided into different groups basing on their gender and cholesterol levels. Since different opioids, morphine, oxycodone, and fentanyl, were all administrated at fixed low dose initially and increased gradually only if pain was not controlled, the percentages of patients in each group who did not respond to the initial doses of opioids and required higher doses for pain management were determined and compared. Results Patients with relative low cholesterol levels have larger percentage (11 out of 28 in female and 31 out of 71 in male) to not respond to the initial dose of opioids than those with high cholesterol levels (0 out of 258 in female and 8 out of 74 in male). Similar differences were obtained when patients with different opioids were analyzed separately. After converting the doses of different opioids to equivalent doses of oxycodone, significant correlation between opioid usages and cholesterol levels was also observed. Conclusions Therefore, more attention should be taken to those cancer patients with low cholesterol levels because they may require higher doses of opioids as pain killer. Electronic supplementary material The online version of this article (doi:10.1186/s12944-016-0212-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Zhenhua Huang
- Department of Oncology, Nanfang Hospital, Southern Medical University, #1838 Guangzhou Ave. N, Guangzhou, 510515, China.
| | - Lining Liang
- CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, A-131, #190 Kaiyuan Ave, Guangzhou, 510530, China.
| | - Lingyu Li
- CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, A-131, #190 Kaiyuan Ave, Guangzhou, 510530, China. .,Anhui University, Hefei, 230601, China.
| | - Miao Xu
- Sun Yat-sen University Cancer Center; State Key Laboratory of Oncology in South China; Collaborative Innovation Center for Cancer Medicine, #651 Dongfeng East Ave, Guangzhou, 510060, China.
| | - Xiang Li
- CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, A-131, #190 Kaiyuan Ave, Guangzhou, 510530, China.
| | - Hao Sun
- CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, A-131, #190 Kaiyuan Ave, Guangzhou, 510530, China.
| | - Songwei He
- CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, A-131, #190 Kaiyuan Ave, Guangzhou, 510530, China.
| | - Lilong Lin
- CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, A-131, #190 Kaiyuan Ave, Guangzhou, 510530, China.
| | - Yixin Zhang
- CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, A-131, #190 Kaiyuan Ave, Guangzhou, 510530, China.
| | - Yancheng Song
- The third hospital, Southern Medical University, #183 Zhongshan Ave. E, Guangzhou, 510665, China.
| | - Man Yang
- Department of Neurology, Nanfang Hospital, Southern Medical University, #1838 Guangzhou Ave. N, Guangzhou, 510515, China.
| | - Yuling Luo
- Department of Oncology, Nanfang Hospital, Southern Medical University, #1838 Guangzhou Ave. N, Guangzhou, 510515, China.
| | - Horace H Loh
- Department of Pharmacology, University of Minnesota, Minneapolis, Minnesota, 6-120 Jackson Hall, 321 Church St. SE, Minneapolis, MN, 55455, USA.
| | - Ping-Yee Law
- Department of Pharmacology, University of Minnesota, Minneapolis, Minnesota, 6-120 Jackson Hall, 321 Church St. SE, Minneapolis, MN, 55455, USA.
| | - Dayong Zheng
- Department of Oncology, Nanfang Hospital, Southern Medical University, #1838 Guangzhou Ave. N, Guangzhou, 510515, China.
| | - Hui Zheng
- CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, A-131, #190 Kaiyuan Ave, Guangzhou, 510530, China.
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31
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Gioia M, Vindigni G, Testa B, Raniolo S, Fasciglione GF, Coletta M, Biocca S. Membrane Cholesterol Modulates LOX-1 Shedding in Endothelial Cells. PLoS One 2015; 10:e0141270. [PMID: 26495844 PMCID: PMC4619672 DOI: 10.1371/journal.pone.0141270] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 10/05/2015] [Indexed: 11/19/2022] Open
Abstract
The lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is a scavenger receptor responsible for ox-LDL recognition, binding and internalization, which is up-regulated during atherogenesis. Its activation triggers endothelium dysfunction and induces inflammation. A soluble form of LOX-1 has been identified in the human blood and its presence considered a biomarker of cardiovascular diseases. We recently showed that cholesterol-lowering drugs inhibit ox-LDL binding and internalization, rescuing the ox-LDL induced apoptotic phenotype in primary endothelial cells. Here we have investigated the molecular bases of human LOX-1 shedding by metalloproteinases and the role of cell membrane cholesterol on the regulation of this event by modulating its level with MβCD and statins. We report that membrane cholesterol affects the release of different forms of LOX-1 in cells transiently and stably expressing human LOX-1 and in a human endothelial cell line (EA.hy926). In particular, our data show that i) cholesterol depletion triggers the release of LOX-1 in exosomes as a full-length transmembrane isoform and as a truncated ectodomain soluble fragment (sLOX-1); ii) endothelial cells secrete a soluble metalloproteinase which induces LOX-1 ectodomain shedding and iii) long term statins treatment enhances sLOX-1 proteolytic shedding.
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Affiliation(s)
- Magda Gioia
- Department of Clinical Sciences and Translational Medicine, University of Rome “Tor Vergata, Via Montpellier 1, 00133, Rome, Italy
| | - Giulia Vindigni
- Department of Systems Medicine, University of Rome “Tor Vergata”, Via Montpellier 1, 00133, Rome, Italy
| | - Barbara Testa
- Department of Systems Medicine, University of Rome “Tor Vergata”, Via Montpellier 1, 00133, Rome, Italy
| | - Sofia Raniolo
- Department of Systems Medicine, University of Rome “Tor Vergata”, Via Montpellier 1, 00133, Rome, Italy
| | - Giovanni Francesco Fasciglione
- Department of Clinical Sciences and Translational Medicine, University of Rome “Tor Vergata, Via Montpellier 1, 00133, Rome, Italy
| | - Massimiliano Coletta
- Department of Clinical Sciences and Translational Medicine, University of Rome “Tor Vergata, Via Montpellier 1, 00133, Rome, Italy
| | - Silvia Biocca
- Department of Systems Medicine, University of Rome “Tor Vergata”, Via Montpellier 1, 00133, Rome, Italy
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32
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Orchestration of membrane receptor signaling by membrane lipids. Biochimie 2015; 113:111-24. [DOI: 10.1016/j.biochi.2015.04.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 04/05/2015] [Indexed: 12/20/2022]
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33
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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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34
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See Hoe LE, Schilling JM, Tarbit E, Kiessling CJ, Busija AR, Niesman IR, Du Toit E, Ashton KJ, Roth DM, Headrick JP, Patel HH, Peart JN. Sarcolemmal cholesterol and caveolin-3 dependence of cardiac function, ischemic tolerance, and opioidergic cardioprotection. Am J Physiol Heart Circ Physiol 2014; 307:H895-903. [PMID: 25063791 DOI: 10.1152/ajpheart.00081.2014] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cholesterol-rich caveolar microdomains and associated caveolins influence sarcolemmal ion channel and receptor function and protective stress signaling. However, the importance of membrane cholesterol content to cardiovascular function and myocardial responses to ischemia-reperfusion (I/R) and cardioprotective stimuli are unclear. We assessed the effects of graded cholesterol depletion with methyl-β-cyclodextrin (MβCD) and lifelong knockout (KO) or overexpression (OE) of caveolin-3 (Cav-3) on cardiac function, I/R tolerance, and opioid receptor (OR)-mediated protection. Langendorff-perfused hearts from young male C57Bl/6 mice were untreated or treated with 0.02-1.0 mM MβCD for 25 min to deplete membrane cholesterol and disrupt caveolae. Hearts were subjected to 25-min ischemia/45-min reperfusion, and the cardioprotective effects of morphine applied either acutely or chronically [sustained ligand-activated preconditioning (SLP)] were assessed. MβCD concentration dependently reduced normoxic contractile function and postischemic outcomes in association with graded (10-30%) reductions in sarcolemmal cholesterol. Cardioprotection with acute morphine was abolished with ≥20 μM MβCD, whereas SLP was more robust and only inhibited with ≥200 μM MβCD. Deletion of Cav-3 also reduced, whereas Cav-3 OE improved, myocardial I/R tolerance. Protection via SLP remained equally effective in Cav-3 KO mice and was additive with innate protection arising with Cav-3 OE. These data reveal the membrane cholesterol dependence of normoxic myocardial and coronary function, I/R tolerance, and OR-mediated cardioprotection in murine hearts (all declining with cholesterol depletion). In contrast, baseline function appears insensitive to Cav-3, whereas cardiac I/R tolerance parallels Cav-3 expression. Novel SLP appears unique, being less sensitive to cholesterol depletion than acute OR protection and arising independently of Cav-3 expression.
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Affiliation(s)
- Louise E See Hoe
- Heart Foundation Research Centre, Griffith Health Institute, Griffith University, Southport, Queensland, Australia
| | - Jan M Schilling
- Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Emiri Tarbit
- Heart Foundation Research Centre, Griffith Health Institute, Griffith University, Southport, Queensland, Australia
| | - Can J Kiessling
- Faculty of Health Sciences and Medicine, Bond University, Robina, Queensland, Australia; and
| | - Anna R Busija
- Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Ingrid R Niesman
- Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Eugene Du Toit
- Heart Foundation Research Centre, Griffith Health Institute, Griffith University, Southport, Queensland, Australia
| | - Kevin J Ashton
- Faculty of Health Sciences and Medicine, Bond University, Robina, Queensland, Australia; and
| | - David M Roth
- Veterans Affairs San Diego Healthcare System, San Diego, California; Department of Anesthesiology, University of California, San Diego, California
| | - John P Headrick
- Heart Foundation Research Centre, Griffith Health Institute, Griffith University, Southport, Queensland, Australia
| | - Hemal H Patel
- Veterans Affairs San Diego Healthcare System, San Diego, California; Department of Anesthesiology, University of California, San Diego, California
| | - Jason N Peart
- Heart Foundation Research Centre, Griffith Health Institute, Griffith University, Southport, Queensland, Australia;
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35
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Ben Haddou T, Malfacini D, Calo G, Aceto MD, Harris LS, Traynor JR, Coop A, Schmidhammer H, Spetea M. Exploring pharmacological activities and signaling of morphinans substituted in position 6 as potent agonists interacting with the μ opioid receptor. Mol Pain 2014; 10:48. [PMID: 25059282 PMCID: PMC4121618 DOI: 10.1186/1744-8069-10-48] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 07/17/2014] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Opioid analgesics are the most effective drugs for the treatment of moderate to severe pain. However, they also produce several adverse effects that can complicate pain management. The μ opioid (MOP) receptor, a G protein-coupled receptor, is recognized as the opioid receptor type which primarily mediates the pharmacological actions of clinically used opioid agonists. The morphinan class of analgesics including morphine and oxycodone are of main importance as therapeutically valuable drugs. Though the natural alkaloid morphine contains a C-6-hydroxyl group and the semisynthetic derivative oxycodone has a 6-carbonyl function, chemical approaches have uncovered that functionalizing position 6 gives rise to a range of diverse activities. Hence, position 6 of N-methylmorphinans is one of the most manipulated sites, and is established to play a key role in ligand binding at the MOP receptor, efficacy, signaling, and analgesic potency. We have earlier reported on a chemically innovative modification in oxycodone resulting in novel morphinans with 6-acrylonitrile incorporated substructures. RESULTS This study describes in vitro and in vivo pharmacological activities and signaling of new morphinans substituted in position 6 with acrylonitrile and amido functions as potent agonists and antinociceptive agents interacting with MOP receptors. We show that the presence of a 6-cyano group in N-methylmorphinans has a strong influence on the binding to the opioid receptors and post-receptor signaling. One 6-cyano-N-methylmorphinan of the series was identified as the highest affinity and most selective MOP agonist, and very potent in stimulating G protein coupling and intracellular calcium release through the MOP receptor. In vivo, this MOP agonist showed to be greatly effective against thermal and chemical nociception in mice with marked increased antinociceptive potency than the lead molecule oxycodone. CONCLUSION Development of such novel chemotypes by targeting position 6 provides valuable insights on ligand-receptor interaction and molecular mode of action, and may aid in identification of opioid therapeutics with enhanced analgesic properties and fewer undesirable effects.
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Affiliation(s)
- Tanila Ben Haddou
- Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, Innsbruck A-6020, Austria
| | - Davide Malfacini
- Department of Medical Sciences, Section of Pharmacology and Italian Institute of Neuroscience, University of Ferrara, Ferrara I-44121, Italy
| | - Girolamo Calo
- Department of Medical Sciences, Section of Pharmacology and Italian Institute of Neuroscience, University of Ferrara, Ferrara I-44121, Italy
| | - Mario D Aceto
- Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, Richmond, VA 23298-0613, USA
| | - Louis S Harris
- Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, Richmond, VA 23298-0613, USA
| | - 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
| | - Andrew Coop
- Department of Pharmaceutical Sciences, University of Maryland, School of Pharmacy, Baltimore, MD 21201, USA
| | - Helmut Schmidhammer
- Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, Innsbruck A-6020, Austria
| | - Mariana Spetea
- Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, Innsbruck A-6020, Austria
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Yu P, Sun M, Villar VAM, Zhang Y, Weinman EJ, Felder RA, Jose PA. Differential dopamine receptor subtype regulation of adenylyl cyclases in lipid rafts in human embryonic kidney and renal proximal tubule cells. Cell Signal 2014; 26:2521-9. [PMID: 25049074 DOI: 10.1016/j.cellsig.2014.07.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 07/09/2014] [Indexed: 01/11/2023]
Abstract
Dopamine D1-like receptors (D1R and D5R) stimulate adenylyl cyclase (AC) activity, whereas the D2-like receptors (D2, D3 and D4) inhibit AC activity. D1R, but not the D5R, has been reported to regulate AC activity in lipid rafts (LRs). We tested the hypothesis that D1R and D5R differentially regulate AC activity in LRs using human embryonic kidney (HEK) 293 cells heterologously expressing human D1 or D5 receptor (HEK-hD1R or HEK-hD5R) and human renal proximal tubule (hRPT) cells that endogenously express D1R and D5R. Of the AC isoforms expressed in HEK and hRPT cells (AC3, AC5, AC6, AC7, and AC9), AC5/6 was distributed to a greater extent in LRs than non-LRs in HEK-hD1R (84.5±2.3% of total), HEK-hD5R (68.9±3.1% of total), and hRPT cells (66.6 ± 2.2% of total) (P<0.05, n=4/group). In HEK-hD1R cells, the D1-like receptor agonist fenoldopam (1 μM/15 min) increased AC5/6 protein (+17.2 ± 3.9% of control) in LRs but decreased it in non-LRs (-47.3±5.3% of control) (P<0.05, vs. control, n=4/group). By contrast, in HEK-hD5R cells, fenoldopam increased AC5/6 protein in non-LRs (+67.1 ± 5.3% of control, P<0.006, vs. control, n=4) but had no effect in LRs. In hRPT cells, fenoldopam increased AC5/6 in LRs but had little effect in non-LRs. Disruption of LRs with methyl-β-cyclodextrin decreased basal AC activity in HEK-D1R (-94.5 ± 2.0% of control) and HEK-D5R cells (-87.1 ± 4.6% of control) but increased it in hRPT cells (6.8±0.5-fold). AC6 activity was stimulated to a greater extent by D1R than D5R, in agreement with the greater colocalization of AC5/6 with D1R than D5R in LRs. We conclude that LRs are essential not only for the proper membrane distribution and maintenance of AC5/6 activity but also for the regulation of D1R- and D5R-mediated AC signaling.
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Affiliation(s)
- Peiying Yu
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - Min Sun
- Department of Biological Sciences, School of Life Science, Anhui University, Anhui, China
| | - Van Anthony M Villar
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - Yanrong Zhang
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - Edward J Weinman
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - Robin A Felder
- Department of Pathology, University of Virginia Health Sciences Center, Charlottesville, VA 22903, United States
| | - Pedro A Jose
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, United States; Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, United States
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G protein-coupled receptors: what a difference a 'partner' makes. Int J Mol Sci 2014; 15:1112-42. [PMID: 24441568 PMCID: PMC3907859 DOI: 10.3390/ijms15011112] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 12/20/2013] [Accepted: 01/08/2014] [Indexed: 01/16/2023] Open
Abstract
G protein-coupled receptors (GPCRs) are important cell signaling mediators, involved in essential physiological processes. GPCRs respond to a wide variety of ligands from light to large macromolecules, including hormones and small peptides. Unfortunately, mutations and dysregulation of GPCRs that induce a loss of function or alter expression can lead to disorders that are sometimes lethal. Therefore, the expression, trafficking, signaling and desensitization of GPCRs must be tightly regulated by different cellular systems to prevent disease. Although there is substantial knowledge regarding the mechanisms that regulate the desensitization and down-regulation of GPCRs, less is known about the mechanisms that regulate the trafficking and cell-surface expression of newly synthesized GPCRs. More recently, there is accumulating evidence that suggests certain GPCRs are able to interact with specific proteins that can completely change their fate and function. These interactions add on another level of regulation and flexibility between different tissue/cell-types. Here, we review some of the main interacting proteins of GPCRs. A greater understanding of the mechanisms regulating their interactions may lead to the discovery of new drug targets for therapy.
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Anderson G, Maes M, Berk M. Schizophrenia is primed for an increased expression of depression through activation of immuno-inflammatory, oxidative and nitrosative stress, and tryptophan catabolite pathways. Prog Neuropsychopharmacol Biol Psychiatry 2013; 42:101-14. [PMID: 22930036 DOI: 10.1016/j.pnpbp.2012.07.016] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 07/25/2012] [Accepted: 07/26/2012] [Indexed: 02/08/2023]
Abstract
Schizophrenia and depression are two common and debilitating psychiatric conditions. Up to 61% of schizophrenic patients have comorbid clinical depression, often undiagnosed. Both share significant overlaps in underlying biological processes, which are relevant to the course and treatment of both conditions. Shared processes include changes in cell-mediated immune and inflammatory pathways, e.g. increased levels of pro-inflammatory cytokines and a Th1 response; activation of oxidative and nitrosative stress (O&NS) pathways, e.g. increased lipid peroxidation, damage to proteins and DNA; decreased antioxidant levels, e.g. lowered coenzyme Q10, vitamin E, glutathione and melatonin levels; autoimmune responses; and activation of the tryptophan catabolite (TRYCAT) pathway through induction of indoleamine-2,3-dioxygenase. Both show cognitive and neurostructural evidence of a neuroprogressive process. Here we review the interlinked nature of these biological processes, suggesting that schizophrenia is immunologically primed for an increased expression of depression. Such a conceptualization explains, and incorporates, many of the current perspectives on the nature of schizophrenia and depression, and has implications for the nature of classification and treatment of both disorders. An early developmental etiology to schizophrenia, driven by maternal infection, with subsequent impact on offspring immuno-inflammatory responses, creates alterations in the immune pathways, which although priming for depression, also differentiates the two disorders.
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Cang X, Du Y, Mao Y, Wang Y, Yang H, Jiang H. Mapping the Functional Binding Sites of Cholesterol in β2-Adrenergic Receptor by Long-Time Molecular Dynamics Simulations. J Phys Chem B 2013; 117:1085-94. [DOI: 10.1021/jp3118192] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xiaohui Cang
- Drug Discovery and
Design Center, State Key Laboratory of Drug Research, Shanghai Institute
of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China
| | - Yun Du
- Drug Discovery and
Design Center, State Key Laboratory of Drug Research, Shanghai Institute
of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China
| | - Yanyan Mao
- Drug Discovery and
Design Center, State Key Laboratory of Drug Research, Shanghai Institute
of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China
| | - Yuanyuan Wang
- Drug Discovery and
Design Center, State Key Laboratory of Drug Research, Shanghai Institute
of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China
| | - Huaiyu Yang
- Drug Discovery and
Design Center, State Key Laboratory of Drug Research, Shanghai Institute
of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China
| | - Hualiang Jiang
- Drug Discovery and
Design Center, State Key Laboratory of Drug Research, Shanghai Institute
of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China
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40
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Williams JT, Ingram SL, Henderson G, Chavkin C, von Zastrow M, Schulz S, Koch T, Evans CJ, Christie MJ. Regulation of μ-opioid receptors: desensitization, phosphorylation, internalization, and tolerance. Pharmacol Rev 2013; 65:223-54. [PMID: 23321159 DOI: 10.1124/pr.112.005942] [Citation(s) in RCA: 593] [Impact Index Per Article: 53.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Morphine and related µ-opioid receptor (MOR) agonists remain among the most effective drugs known for acute relief of severe pain. A major problem in treating painful conditions is that tolerance limits the long-term utility of opioid agonists. Considerable effort has been expended on developing an understanding of the molecular and cellular processes that underlie acute MOR signaling, short-term receptor regulation, and the progression of events that lead to tolerance for different MOR agonists. Although great progress has been made in the past decade, many points of contention and controversy cloud the realization of this progress. This review attempts to clarify some confusion by clearly defining terms, such as desensitization and tolerance, and addressing optimal pharmacological analyses for discerning relative importance of these cellular mechanisms. Cellular and molecular mechanisms regulating MOR function by phosphorylation relative to receptor desensitization and endocytosis are comprehensively reviewed, with an emphasis on agonist-biased regulation and areas where knowledge is lacking or controversial. The implications of these mechanisms for understanding the substantial contribution of MOR signaling to opioid tolerance are then considered in detail. While some functional MOR regulatory mechanisms contributing to tolerance are clearly understood, there are large gaps in understanding the molecular processes responsible for loss of MOR function after chronic exposure to opioids. Further elucidation of the cellular mechanisms that are regulated by opioids will be necessary for the successful development of MOR-based approaches to new pain therapeutics that limit the development of tolerance.
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Affiliation(s)
- John T Williams
- Vollum Institute, Oregon Health Sciences University, Portland, Oregon, USA
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41
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Membrane cholesterol affects stimulus-activity coupling in type 1, but not type 2, CCK receptors: use of cell lines with elevated cholesterol. Lipids 2013; 48:231-44. [PMID: 23306829 DOI: 10.1007/s11745-012-3744-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Accepted: 10/25/2012] [Indexed: 10/27/2022]
Abstract
The lipid microenvironment of membrane proteins can affect their structure, function, and regulation. We recently described differential effects of acute modification of membrane cholesterol on the function of type 1 and 2 cholecystokinin (CCK) receptors. We now explore the regulatory impact of chronic cholesterol modification on these receptors using novel receptor-bearing cell lines with elevated membrane cholesterol. Stable CCK1R and CCK2R expression was established in clonal lines of 25RA cells having gain-of-function in SCAP [sterol regulatory element binding protein (SREBP) cleavage-activating protein] and SRD15 cells having deficiencies in Insig-1 and Insig-2 enzymes affecting HMG CoA reductase and SREBP. Increased cholesterol in the plasma membrane of these cells was directly demonstrated, and receptor binding and signaling characteristics were shown to reflect predicted effects on receptor function. In both environments, both types of CCK receptors were internalized and recycled normally in response to agonist occupation. No differences in receptor distribution within the membrane were appreciated at the light microscopic level in these CHO-derived cell lines. Fluorescence anisotropy was studied for these receptors occupied by fluorescent agonist and antagonist, as well as when tagged with YFP. These studies demonstrated increased anisotropy of the agonist ligand occupying the active state of the CCK1R in a cholesterol-enriched environment, mimicking fluorescence of the uncoupled, inactive state of this receptor, while there was no effect of increasing cholesterol on fluorescence at the CCK2R. These cell lines should be quite useful for examining the functional characteristics of potential drugs that might be used in an abnormal lipid environment.
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42
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Ibrahim S, McCartney A, Markosyan N, Smyth EM. Heterodimerization with the prostacyclin receptor triggers thromboxane receptor relocation to lipid rafts. Arterioscler Thromb Vasc Biol 2012; 33:60-6. [PMID: 23162015 DOI: 10.1161/atvbaha.112.300536] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
OBJECTIVE Prostacyclin and thromboxane mediate opposing cardiovascular actions through receptors termed IP and TP, respectively. When dimerized with IP, the TP shifts to IP-like function. IP localizes to cholesterol-enriched membrane rafts, but TP and IPTP heterodimer localization is not defined. We examined these receptors' membrane localization and the role of rafts in receptor function. METHODS AND RESULTS Microdomain distribution of IP, TP, and IPTP heterodimers was examined in COS-7 cells by measuring energy transfer from renilla luciferase-fused receptors to fluorescently labeled rafts. IP raft association was confirmed. TP was raft excluded, but redistributed to rafts upon dimerization with IP. Signaling of the IP and IPTP heterodimer, but not TP alone, was suppressed after raft disruption by cholesterol depletion. Cholesterol enrichment also selectively suppressed IP and IPTP function. Native IP and IPTP signaling in smooth muscle cells and macrophages were similarly sensitive to cholesterol manipulation, whereas macrophages from hypercholesterolemic mice displayed suppressed IP and IPTP function. CONCLUSIONS IP and TP function within distinct microdomains. Raft incorporation of TP in the IPTP heterodimer likely facilitates its signaling shift. We speculate that changes in IP and IPTP signaling after perturbation of membrane cholesterol may contribute to cardiovascular disease associated with hypercholesterolemia.
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Affiliation(s)
- Salam Ibrahim
- Institute for Translational Medicine, University of Pennsylvania, Philadelphia, PA, USA
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43
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Oates J, Faust B, Attrill H, Harding P, Orwick M, Watts A. The role of cholesterol on the activity and stability of neurotensin receptor 1. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2012; 1818:2228-33. [DOI: 10.1016/j.bbamem.2012.04.010] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Revised: 03/15/2012] [Accepted: 04/12/2012] [Indexed: 10/28/2022]
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Oates J, Watts A. Uncovering the intimate relationship between lipids, cholesterol and GPCR activation. Curr Opin Struct Biol 2011; 21:802-7. [DOI: 10.1016/j.sbi.2011.09.007] [Citation(s) in RCA: 185] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Revised: 09/23/2011] [Accepted: 09/29/2011] [Indexed: 11/16/2022]
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45
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Arttamangkul S, Lau EK, Lu HW, Williams JT. Desensitization and trafficking of μ-opioid receptors in locus ceruleus neurons: modulation by kinases. Mol Pharmacol 2011; 81:348-55. [PMID: 22113080 DOI: 10.1124/mol.111.076208] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The phosphorylation of μ-opioid receptors (MOPRs) by G protein-coupled receptor kinases (GRKs), followed by arrestin binding, is thought to be a key pathway leading to desensitization and internalization. The present study used the combination of intracellular and whole-cell recordings from rats and mice, as well as live cell imaging of Flag-tagged MOPRs from mouse locus ceruleus neurons, to examine the role of protein kinases in acute desensitization and receptor trafficking. Inhibition of GRKs by using heparin or GRK2-mutant mice did not block desensitization or alter the rate of recovery from desensitization. The nonselective kinase inhibitor staurosporine did not reduce the extent of [Met(5)]enkephalin (ME)-induced desensitization but increased the rate of recovery from desensitization. In the presence of staurosporine, ME-activated FlagMOPRs were internalized but did not traffic away from the plasma membrane. The increased rate of recovery from desensitization correlated with the enhancement in the recycling of receptors to the plasma membrane. ME-induced MOPR desensitization persisted and the trafficking of receptors was modified after inhibition of protein kinases. The results suggest that desensitization of MOPRs may be an early step after agonist binding that is modulated by but is not dependent on kinase activity.
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46
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Thompson AA, Liu JJ, Chun E, Wacker D, Wu H, Cherezov V, Stevens RC. GPCR stabilization using the bicelle-like architecture of mixed sterol-detergent micelles. Methods 2011; 55:310-7. [PMID: 22041719 DOI: 10.1016/j.ymeth.2011.10.011] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Revised: 10/18/2011] [Accepted: 10/18/2011] [Indexed: 12/30/2022] Open
Abstract
The biophysical characterization of purified membrane proteins typically requires detergent mediated extraction from native lipid membrane environments. In the case of human G protein-coupled receptors (GPCRs), this process has been complicated by their conformational heterogeneity and the general lack of understanding the composition and interactions within the diverse human cellular membrane environment. Several successful GPCR structure determination efforts have shown that the addition of cholesterol analogs is often critical for maintaining protein stability. We have identified sterols that substantially increase the stability of the NOP receptor (ORL-1), a member of the opioid GPCR family, in a mixed micelle environment. Using dynamic light scattering and small-angle X-ray scattering, we have determined that the most thermal stabilizing sterol, cholesteryl hemisuccinate, induces the formation of a bicelle-like micelle architecture when mixed with dodecyl maltoside detergent. Together with mutagenesis studies and recent GPCR structures, our results provide indications that stabilization is attained through a combination of specific sterol binding to GPCRs and modulation of micelle morphology.
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Affiliation(s)
- Aaron A Thompson
- Department of Molecular Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
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47
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Potter RM, Harikumar KG, Wu SV, Miller LJ. Differential sensitivity of types 1 and 2 cholecystokinin receptors to membrane cholesterol. J Lipid Res 2011; 53:137-48. [PMID: 22021636 DOI: 10.1194/jlr.m020065] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Recent studies indicate that membrane cholesterol can associate with G protein-coupled receptors (GPCRs) and affect their function. Previously, we reported that manipulation of membrane cholesterol affects ligand binding and signal transduction of the type 1 cholecystokinin receptor (CCK1R), a Class A GPCR. We now demonstrate that the closely related type 2 cholecystokinin receptor (CCK2R) does not share this cholesterol sensitivity. The sequences of both receptors reveal almost identical cholesterol interaction motifs in analogous locations in transmembrane segments two, three, four, and five. The disparity in cholesterol sensitivity between these receptors, despite their close structural relationship, provides a unique opportunity to define the possible structural basis of cholesterol sensitivity of CCK1R. To evaluate the relative contributions of different regions of CCK1R to cholesterol sensitivity, we performed ligand binding studies and biological activity assays of wild-type and CCK2R/CCK1R chimeric receptor-bearing Chinese hamster ovary cells after manipulation of membrane cholesterol. We also extended these studies to site-directed mutations within the cholesterol interaction motifs. The results contribute to a better understanding of the structural requirements for cholesterol sensitivity in CCK1R and provides insight into the function of other cholesterol-sensitive Class A GPCRs.
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Affiliation(s)
- Ross M Potter
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ 85259, USA
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48
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Qiu Y, Wang Y, Law PY, Chen HZ, Loh HH. Cholesterol regulates micro-opioid receptor-induced beta-arrestin 2 translocation to membrane lipid rafts. Mol Pharmacol 2011; 80:210-8. [PMID: 21518774 DOI: 10.1124/mol.110.070870] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
μ-Opioid receptor (OPRM1) is mainly localized in lipid raft microdomains but internalizes through clathrin-dependent pathways. Our previous studies demonstrated that disruption of lipid rafts by cholesterol-depletion reagent blocked the agonist-induced internalization of OPRM1 and G protein-dependent signaling. The present study demonstrated that reduction of cholesterol level decreased and culturing cells in excess cholesterol increased the agonist-induced internalization and desensitization of OPRM1, respectively. Further analyses indicated that modulation of cellular cholesterol level did not affect agonist-induced receptor phosphorylation but did affect membrane translocation of β-arrestins. The translocation of β-arrestins was blocked by cholesterol reduction, and the effect could be reversed by incubating with cholesterol. OptiPrep gradient separation of lipid rafts revealed that excess cholesterol retained more receptors in lipid raft domains and facilitated the recruitment of β-arrestins to these microdomains upon agonist activation. Moreover, excess cholesterol could evoke receptor internalization and protein kinase C-independent extracellular signal-regulated kinases activation upon morphine treatment. Therefore, these results suggest that cholesterol not only can influence OPRM1 localization in lipid rafts but also can effectively enhance the recruitment of β-arrestins and thereby affect the agonist-induced trafficking and agonist-dependent signaling of OPRM1.
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Affiliation(s)
- Yu Qiu
- Department of Pharmacology, University of Minnesota, Minnesota 55455-0217, USA
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49
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Abstract
This paper is the 32nd consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2009 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, USA.
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50
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Agarwal SR, MacDougall DA, Tyser R, Pugh SD, Calaghan SC, Harvey RD. Effects of cholesterol depletion on compartmentalized cAMP responses in adult cardiac myocytes. J Mol Cell Cardiol 2010; 50:500-9. [PMID: 21115018 PMCID: PMC3049871 DOI: 10.1016/j.yjmcc.2010.11.015] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2010] [Revised: 10/27/2010] [Accepted: 11/16/2010] [Indexed: 11/02/2022]
Abstract
β(1)-Adrenergic receptors (β(1)ARs) and E-type prostaglandin receptors (EPRs) both produce compartmentalized cAMP responses in cardiac myocytes. The role of cholesterol-dependent lipid rafts in producing these compartmentalized responses was investigated in adult rat ventricular myocytes. β(1)ARs were found in lipid raft and non-lipid raft containing membrane fractions, while EPRs were only found in non-lipid raft fractions. Furthermore, β(1)AR activation enhanced the L-type Ca(2+) current, intracellular Ca(2+) transient, and myocyte shortening, while EPR activation had no effect, consistent with the idea that these functional responses are regulated by cAMP produced by receptors found in lipid raft domains. Using methyl-β-cyclodextrin to disrupt lipid rafts by depleting membrane cholesterol did not eliminate compartmentalized behavior, but it did selectively alter specific receptor-mediated responses. Cholesterol depletion enhanced the sensitivity of functional responses produced by β(1)ARs without having any effect on EPR activation. Changes in cAMP activity were also measured in intact cells using two different FRET-based biosensors: a type II PKA-based probe to monitor cAMP in subcellular compartments that include microdomains associated with caveolar lipid rafts and a freely diffusible Epac2-based probe to monitor total cytosolic cAMP. β(1)AR and EPR activation elicited responses detected by both FRET probes. However, cholesterol depletion only affected β(1)AR responses detected by the PKA probe. These results indicate that lipid rafts alone are not sufficient to explain the difference between β(1)AR and EPR responses. They also suggest that β(1)AR regulation of myocyte contraction involves the local production of cAMP by a subpopulation of receptors associated with caveolar lipid rafts.
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Affiliation(s)
- Shailesh R Agarwal
- Department of Pharmacology-MS318, University of Nevada School of Medicine, Reno, NV 89557, USA
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