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Kovacs T, Nagy P, Panyi G, Szente L, Varga Z, Zakany F. Cyclodextrins: Only Pharmaceutical Excipients or Full-Fledged Drug Candidates? Pharmaceutics 2022; 14:pharmaceutics14122559. [PMID: 36559052 PMCID: PMC9788615 DOI: 10.3390/pharmaceutics14122559] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 11/15/2022] [Accepted: 11/18/2022] [Indexed: 11/23/2022] Open
Abstract
Cyclodextrins, representing a versatile family of cyclic oligosaccharides, have extensive pharmaceutical applications due to their unique truncated cone-shaped structure with a hydrophilic outer surface and a hydrophobic cavity, which enables them to form non-covalent host-guest inclusion complexes in pharmaceutical formulations to enhance the solubility, stability and bioavailability of numerous drug molecules. As a result, cyclodextrins are mostly considered as inert carriers during their medical application, while their ability to interact not only with small molecules but also with lipids and proteins is largely neglected. By forming inclusion complexes with cholesterol, cyclodextrins deplete cholesterol from cellular membranes and thereby influence protein function indirectly through alterations in biophysical properties and lateral heterogeneity of bilayers. In this review, we summarize the general chemical principles of direct cyclodextrin-protein interactions and highlight, through relevant examples, how these interactions can modify protein functions in vivo, which, despite their huge potential, have been completely unexploited in therapy so far. Finally, we give a brief overview of disorders such as Niemann-Pick type C disease, atherosclerosis, Alzheimer's and Parkinson's disease, in which cyclodextrins already have or could have the potential to be active therapeutic agents due to their cholesterol-complexing or direct protein-targeting properties.
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Affiliation(s)
- Tamas Kovacs
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Peter Nagy
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Gyorgy Panyi
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Lajos Szente
- CycloLab Cyclodextrin R & D Laboratory Ltd., H-1097 Budapest, Hungary
| | - Zoltan Varga
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Florina Zakany
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
- Correspondence:
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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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Xu C, Fan W, Zhang Y, Loh HH, Law PY. Kappa opioid receptor controls neural stem cell differentiation via a miR-7a/Pax6 dependent pathway. Stem Cells 2021; 39:600-616. [PMID: 33452745 DOI: 10.1002/stem.3334] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 12/28/2020] [Indexed: 01/04/2023]
Abstract
Although the roles of opioid receptors in neurogenesis have been implicated in previous studies, the mechanism by which κ-opioid receptor (OPRK1) regulates adult neurogenesis remains elusive. We now demonstrate that two agonists of OPRK1, U50,488H and dynorphin A, inhibit adult neurogenesis by hindering neuronal differentiation of mouse hippocampal neural stem cells (NSCs), both in vitro and in vivo. This effect was blocked by nor-binaltorphimine (nor-BNI), a specific antagonist of OPRK1. By examining neurogenesis-related genes, we found that OPRK1 agonists were able to downregulate the expression of Pax6, Neurog2, and NeuroD1 in mouse hippocampal NSCs, in a way that Pax6 regulates the transcription of Neurog2 and Neurod1 by directly interacting with their promoters. Moreover, this effect of OPRK1 was accomplished by inducing expression of miR-7a, a miRNA that specifically targeted Pax6 by direct interaction with its 3'-UTR sequence, and thereby decreased the levels of Pax6, Neurog2, and NeuroD1, thus resulted in hindrance of neuronal differentiation of NSCs. Thus, by modulating Pax6/Neurog2/NeuroD1 activities via upregulation of miR-7a expression, OPRK1 agonists hinder the neuronal differentiation of NSCs and hence inhibit adult neurogenesis in mouse hippocampus.
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Affiliation(s)
- Chi Xu
- Department of Neurobiology and Acupuncture Research, The Third Clinical Medical College, Zhejiang Chinese Medical University, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Hangzhou, People's Republic of China
| | - Wenxiang Fan
- Department of Pharmacy, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, People's Republic of China
| | - Ying Zhang
- Department of Neurobiology and Acupuncture Research, The Third Clinical Medical College, Zhejiang Chinese Medical University, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Hangzhou, People's Republic of China
| | - Horace H Loh
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Ping-Yee Law
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
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Direct and indirect cholesterol effects on membrane proteins with special focus on potassium channels. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1865:158706. [DOI: 10.1016/j.bbalip.2020.158706] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 03/19/2020] [Accepted: 03/30/2020] [Indexed: 12/16/2022]
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Chen J, Liang L, Li Y, Zhang Y, Zhang M, Yang T, Meng F, Lai X, Li C, He J, He M, Xu Q, Li Q, Law P, Loh HH, Pei D, Sun H, Zheng H. Naloxone regulates the differentiation of neural stem cells via a receptor‐independent pathway. FASEB J 2020; 34:5917-5930. [DOI: 10.1096/fj.201902873r] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 02/24/2020] [Accepted: 02/26/2020] [Indexed: 11/11/2022]
Affiliation(s)
- Jinlong Chen
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences of Guangzhou Medical University Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences Guangzhou China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory Guangzhou China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine Guangzhou China
- University of Chinese Academy of Sciences Beijing China
| | - Lining Liang
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences of Guangzhou Medical University Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences Guangzhou China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory Guangzhou China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine Guangzhou China
| | - Yuan Li
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences of Guangzhou Medical University Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences Guangzhou China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory Guangzhou China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine Guangzhou China
| | - Yixin Zhang
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences of Guangzhou Medical University Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences Guangzhou China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory Guangzhou China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine Guangzhou China
- University of Chinese Academy of Sciences Beijing China
| | - Mengdan Zhang
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences of Guangzhou Medical University Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences Guangzhou China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory Guangzhou China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine Guangzhou China
- University of Chinese Academy of Sciences Beijing China
| | - Tingting Yang
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences of Guangzhou Medical University Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences Guangzhou China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory Guangzhou China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine Guangzhou China
- University of Chinese Academy of Sciences Beijing China
| | - Fei Meng
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences of Guangzhou Medical University Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences Guangzhou China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory Guangzhou China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine Guangzhou China
- University of Chinese Academy of Sciences Beijing China
| | - Xiaowei Lai
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences of Guangzhou Medical University Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences Guangzhou China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory Guangzhou China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine Guangzhou China
- University of Chinese Academy of Sciences Beijing China
| | - Changpeng Li
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences of Guangzhou Medical University Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences Guangzhou China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory Guangzhou China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine Guangzhou China
| | - Jingcai He
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences of Guangzhou Medical University Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences Guangzhou China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory Guangzhou China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine Guangzhou China
| | - Meiai He
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences of Guangzhou Medical University Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences Guangzhou China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory Guangzhou China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine Guangzhou China
- University of Chinese Academy of Sciences Beijing China
| | - Qiaoran Xu
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences of Guangzhou Medical University Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences Guangzhou China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory Guangzhou China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine Guangzhou China
- University of Chinese Academy of Sciences Beijing China
| | - Qian Li
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences of Guangzhou Medical University Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences Guangzhou China
| | - Ping‐Yee Law
- Department of Pharmacology University of Minnesota Minneapolis MN USA
| | - Horace H. Loh
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory Guangzhou China
- Department of Pharmacology University of Minnesota Minneapolis MN USA
| | - Duanqing Pei
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences of Guangzhou Medical University Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences Guangzhou China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory Guangzhou China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine Guangzhou China
- University of Chinese Academy of Sciences Beijing China
- Institutes for Stem Cell and Regeneration Chinese Academy of Sciences Beijing China
| | - Hao Sun
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences of Guangzhou Medical University Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences Guangzhou China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory Guangzhou China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine Guangzhou China
- University of Chinese Academy of Sciences Beijing China
| | - Hui Zheng
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences of Guangzhou Medical University Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences Guangzhou China
- Guangzhou Regenerative Medicine and Health Guangdong Laboratory Guangzhou China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine Guangzhou China
- University of Chinese Academy of Sciences Beijing China
- Institutes for Stem Cell and Regeneration Chinese Academy of Sciences Beijing China
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Khalid E, Chang JP. β-Arrestin-dependent signaling in GnRH control of hormone secretion from goldfish gonadotrophs and somatotrophs. Gen Comp Endocrinol 2020; 287:113340. [PMID: 31778712 DOI: 10.1016/j.ygcen.2019.113340] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 11/20/2019] [Accepted: 11/22/2019] [Indexed: 12/17/2022]
Abstract
In goldfish, two native isoforms of gonadotropin-releasing hormone (GnRH2 and GnRH3) stimulate luteinizing hormone (LH) and growth hormone (GH) release from pituitary cells through activation of cell-surface GnRH-receptors (GnRHRs) on gonadotrophs and somatotrophs. Interestingly, GnRH2 and GnRH3 induce LH and GH release via non-identical post-receptor signal transduction pathways in a ligand- and cell-type-selective manner. In this study, we examined the involvement of β-arrestins in the control of GnRH-induced LH and GH secretion from dispersed goldfish pituitary cells. Treatment with Barbadin, which interferes with β-arrestin and β2-adaptin subunit interaction, reduced LH responses to GnRH2 and GnRH3, as well as GH responses to GnRH2; but enhanced GnRH3-induced GH secretion. Barbadin also had positive influences on basal hormone release, and basal GH release in particular, as well as basal activity of extracellular signal-regulated kinase (ERK) and GnRH-induced ERK activation. These findings indicate that β-arrestins play permissive roles in the control of GnRH-stimulated LH release. However, in somatotrophs, β-arrestins, perhaps by mediating agonist-selective endosomal trafficking of engaged GnRHRs, participate in GnRH-isoform-specific GH release responses (stimulatory and inhibitory for GnRH2-GnRHR and GnRH3-GnRHR activation, respectively). The correlative stimulatory influences of Barbadin on basal hormone release and ERK activation suggest that β-arrestins may negatively regulate basal secretion through modulation of basal ERK activity. These results provide the first direct evidence of a role for β-arrestins in hormone secretion from an untransformed primary pituitary cell model, and establish these proteins as important receptor-proximal players in mediating functional selectivity downstream of goldfish GnRHRs.
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Affiliation(s)
- Enezi Khalid
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G2E9, Canada
| | - John P Chang
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G2E9, Canada.
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Gondin AB, Halls ML, Canals M, Briddon SJ. GRK Mediates μ-Opioid Receptor Plasma Membrane Reorganization. Front Mol Neurosci 2019; 12:104. [PMID: 31118885 PMCID: PMC6504784 DOI: 10.3389/fnmol.2019.00104] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 04/08/2019] [Indexed: 12/19/2022] Open
Abstract
Differential regulation of the μ-opioid receptor (MOP) has been linked to the development of opioid tolerance and dependence which both limit the clinical use of opioid analgesics. At a cellular level, MOP regulation occurs via receptor phosphorylation, desensitization, plasma membrane redistribution, and internalization. Here, we used fluorescence correlation spectroscopy (FCS) and fluorescence recovery after photobleaching (FRAP) to detect and quantify ligand-dependent changes in the plasma membrane organization of MOP expressed in human embryonic kidney (HEK293) cells. The low internalizing agonist morphine and the antagonist naloxone did not alter constitutive MOP plasma membrane organization. In contrast, the internalizing agonist DAMGO changed MOP plasma membrane organization in a pertussis toxin-insensitive manner and by two mechanisms. Firstly, it slowed MOP diffusion in a manner that was independent of internalization but dependent on GRK2/3. Secondly, DAMGO reduced the surface receptor number and the proportion of mobile receptors, and increased receptor clustering in a manner that was dependent on clathrin-mediated endocytosis. Overall, these results suggest the existence of distinct sequential MOP reorganization events at the plasma membrane and provide insights into the specific protein interactions that control MOP plasma membrane organization.
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Affiliation(s)
- Arisbel B Gondin
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, VIC, Australia.,Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham, United Kingdom.,Centre of Membrane Proteins and Receptors, Universities of Birmingham and Nottingham, The Midlands, United Kingdom
| | - Michelle L Halls
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, VIC, Australia
| | - Meritxell Canals
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, VIC, Australia.,Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham, United Kingdom.,Centre of Membrane Proteins and Receptors, Universities of Birmingham and Nottingham, The Midlands, United Kingdom
| | - Stephen J Briddon
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham, United Kingdom.,Centre of Membrane Proteins and Receptors, Universities of Birmingham and Nottingham, The Midlands, United Kingdom
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Signaling characteristics and functional regulation of delta opioid-kappa opioid receptor (DOP-KOP) heteromers in peripheral sensory neurons. Neuropharmacology 2019; 151:208-218. [PMID: 30776373 PMCID: PMC6500751 DOI: 10.1016/j.neuropharm.2019.02.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 02/01/2019] [Accepted: 02/12/2019] [Indexed: 12/12/2022]
Abstract
Receptor heteromers often display distinct pharmacological and functional properties compared to the individual receptor constituents. In this study, we compared the properties of the DOP-KOP heteromer agonist, 6'-guanidinonaltrindole (6'-GNTI), with agonists for DOP ([D-Pen2,5]-enkephalin [DPDPE]) and KOP (U50488) in peripheral sensory neurons in culture and in vivo. In primary cultures, all three agonists inhibited PGE2-stimulated cAMP accumulation as well as activated extracellular signal-regulated kinase 1/2 (ERK) with similar efficacy. ERK activation by U50488 was Gi-protein mediated but that by DPDPE or 6'-GNTI was Gi-protein independent (i.e., pertussis toxin insensitive). Brief pretreatment with DPDPE or U50488 resulted in loss of cAMP signaling, however, no desensitization occurred with 6'-GNTI pretreatment. In vivo, following intraplantar injection, all three agonists reduced thermal nociception. The dose-response curves for DPDPE and 6'-GNTI were monotonic whereas the curve for U50488 was an inverted U-shape. Inhibition of ERK blocked the downward phase and shifted the curve for U50488 to the right. Following intraplantar injection of carrageenan, antinociceptive responses to either DPDPE or U50488 were transient but could be prolonged with inhibitors of 12/15-lipoxgenases (LOX). By contrast, responsiveness to 6'-GNTI remained for a prolonged time in the absence of LOX inhibitors. Further, pretreatment with the 12/15-LOX metabolites, 12- and 15- hydroxyeicosatetraenoic acid, abolished responses to U50488 and DPDPE but had no effect on 6'-GNTI-mediated responses either in cultures or in vivo. Overall, these results suggest that DOP-KOP heteromers exhibit unique signaling and functional regulation in peripheral sensory neurons and may be a promising therapeutic target for the treatment of pain.
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Melo Z, Ishida C, Goldaraz MDLP, Rojo R, Echavarria R. Novel Roles of Non-Coding RNAs in Opioid Signaling and Cardioprotection. Noncoding RNA 2018; 4:ncrna4030022. [PMID: 30227648 PMCID: PMC6162605 DOI: 10.3390/ncrna4030022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 09/10/2018] [Accepted: 09/12/2018] [Indexed: 12/16/2022] Open
Abstract
Cardiovascular disease (CVD) is a significant cause of morbidity and mortality across the world. A large proportion of CVD deaths are secondary to coronary artery disease (CAD) and myocardial infarction (MI). Even though prevention is the best strategy to reduce risk factors associated with MI, the use of cardioprotective interventions aimed at improving patient outcomes is of great interest. Opioid conditioning has been shown to be effective in reducing myocardial ischemia-reperfusion injury (IRI) and cardiomyocyte death. However, the molecular mechanisms behind these effects are under investigation and could provide the basis for the development of novel therapeutic approaches in the treatment of CVD. Non-coding RNAs (ncRNAs), which are functional RNA molecules that do not translate into proteins, are critical modulators of cardiac gene expression during heart development and disease. Moreover, ncRNAs such as microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) are known to be induced by opioid receptor activation and regulate opioid signaling pathways. Recent advances in experimental and computational tools have accelerated the discovery and functional characterization of ncRNAs. In this study, we review the current understanding of the role of ncRNAs in opioid signaling and opioid-induced cardioprotection.
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Affiliation(s)
- Zesergio Melo
- CONACyT-Centro de Investigacion Biomedica de Occidente, Instituto Mexicano del Seguro Social, Sierra Mojada #800 Col. Independencia, Guadalajara 44340, Jalisco, Mexico.
| | - Cecilia Ishida
- Programa de Genomica Computacional, Centro de Ciencias Genomicas, Universidad Nacional Autonoma de Mexico, Cuernavaca 62210, Morelos, Mexico.
| | - Maria de la Paz Goldaraz
- Departamento de Anestesiologia, Hospital de Especialidades UMAE CMNO, Instituto Mexicano del Seguro Social, Guadalajara 44340, Jalisco, Mexico.
| | - Rocio Rojo
- Departamento de Anestesiologia, Hospital de Especialidades UMAE CMNO, Instituto Mexicano del Seguro Social, Guadalajara 44340, Jalisco, Mexico.
| | - Raquel Echavarria
- CONACyT-Centro de Investigacion Biomedica de Occidente, Instituto Mexicano del Seguro Social, Sierra Mojada #800 Col. Independencia, Guadalajara 44340, Jalisco, Mexico.
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Ujcikova H, Hlouskova M, Cechova K, Stolarova K, Roubalova L, Svoboda P. Determination of μ-, δ- and κ-opioid receptors in forebrain cortex of rats exposed to morphine for 10 days: Comparison with animals after 20 days of morphine withdrawal. PLoS One 2017; 12:e0186797. [PMID: 29053731 PMCID: PMC5650167 DOI: 10.1371/journal.pone.0186797] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 10/06/2017] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Chronic exposure of mammalian organism to morphine results in adaption to persistent high opioid tone through homeostatic adjustments. Our previous results indicated that in the frontal brain cortex (FBC) of rats exposed to morphine for 10 days, such a compensatory adjustment was detected as large up-regulation of adenylylcyclases I (8-fold) and II (2.5-fold). The other isoforms of AC (III-IX) were unchanged. Importantly, the increase of ACI and ACII was reversible as it disappeared after 20 days of morphine withdrawal. Changes of down-stream signaling molecules such as G proteins and adenylylcyclases should respond to and be preceded by primary changes proceeding at receptor level. Therefore in our present work, we addressed the problem of reversibility of the long-term morphine effects on μ-, δ- and κ-OR protein levels in FBC. METHODS Rats were exposed to increasing doses of morphine (10-40 mg/kg) for 10 days and sacrificed either 24 h (group +M10) or 20 days (group +M10/-M20) after the last dose of morphine in parallel with control animals (groups -M10 and -M10/-M20). Post-nuclear supernatant (PNS) fraction was prepared from forebrain cortex, resolved by 1D-SDS-PAGE under non-dissociated (-DTT) and dissociated (+DTT) conditions, and analyzed for the content of μ-, δ- and κ-OR by immunoblotting with C- and N-terminus oriented antibodies. RESULTS Significant down-regulation of δ-OR form exhibiting Mw ≈ 60 kDa was detected in PNS prepared from both (+M10) and (+M10/-M20) rats. However, the total immunoblot signals of μ-, δ- and κ-OR, respectively, were unchanged. Plasma membrane marker Na, K-ATPase, actin and GAPDH were unaffected by morphine in both types of PNS. Membrane-domain marker caveolin-1 and cholesterol level increased in (+M10) rats and this increase was reversed back to control level in (+M10/-M20) rats. CONCLUSIONS In FBC, prolonged exposure of rats to morphine results in minor (δ-OR) or no change (μ- and κ-OR) of opioid receptor content. The reversible increases of caveolin-1 and cholesterol levels suggest participation of membrane domains in compensatory responses during opioid withdrawal. GENERAL SIGNIFICANCE Analysis of reversibility of morphine effect on mammalian brain.
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MESH Headings
- Animals
- Blotting, Western
- Electrophoresis, Gel, Two-Dimensional
- Electrophoresis, Polyacrylamide Gel
- Male
- Morphine/administration & dosage
- Morphine/adverse effects
- Prosencephalon/metabolism
- Rats
- Rats, Wistar
- Receptors, Opioid, delta/metabolism
- Receptors, Opioid, kappa/metabolism
- Receptors, Opioid, mu/metabolism
- Substance Withdrawal Syndrome
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Affiliation(s)
- Hana Ujcikova
- Department of Biomathematics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Martina Hlouskova
- Department of Biomathematics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Kristina Cechova
- Department of Biomathematics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
- Department of Biochemistry, Faculty of Science, Charles University in Prague, Prague, Czech Republic
| | - Katerina Stolarova
- Department of Biomathematics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Lenka Roubalova
- Department of Biomathematics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Petr Svoboda
- Department of Biomathematics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
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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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Chen JJ, Boehning D. Protein Lipidation As a Regulator of Apoptotic Calcium Release: Relevance to Cancer. Front Oncol 2017; 7:138. [PMID: 28706877 PMCID: PMC5489567 DOI: 10.3389/fonc.2017.00138] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 06/16/2017] [Indexed: 12/16/2022] Open
Abstract
Calcium is a critical regulator of cell death pathways. One of the most proximal events leading to cell death is activation of plasma membrane and endoplasmic reticulum-resident calcium channels. A large body of evidence indicates that defects in this pathway contribute to cancer development. Although we have a thorough understanding of how downstream elevations in cytosolic and mitochondrial calcium contribute to cell death, it is much less clear how calcium channels are activated upstream of the apoptotic stimulus. Recently, it has been shown that protein lipidation is a potent regulator of apoptotic signaling. Although classically thought of as a static modification, rapid and reversible protein acylation has emerged as a new signaling paradigm relevant to many pathways, including calcium release and cell death. In this review, we will discuss the role of protein lipidation in regulating apoptotic calcium signaling with direct therapeutic relevance to cancer.
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Affiliation(s)
- Jessica J Chen
- Department of Biochemistry and Molecular Biology, McGovern Medical School, UTHealth, Houston, TX, United States
| | - Darren Boehning
- Department of Biochemistry and Molecular Biology, McGovern Medical School, UTHealth, Houston, TX, United States
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13
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Stone MJ, Hayward JA, Huang C, E Huma Z, Sanchez J. Mechanisms of Regulation of the Chemokine-Receptor Network. Int J Mol Sci 2017; 18:E342. [PMID: 28178200 PMCID: PMC5343877 DOI: 10.3390/ijms18020342] [Citation(s) in RCA: 184] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 01/18/2017] [Accepted: 01/26/2017] [Indexed: 12/18/2022] Open
Abstract
The interactions of chemokines with their G protein-coupled receptors promote the migration of leukocytes during normal immune function and as a key aspect of the inflammatory response to tissue injury or infection. This review summarizes the major cellular and biochemical mechanisms by which the interactions of chemokines with chemokine receptors are regulated, including: selective and competitive binding interactions; genetic polymorphisms; mRNA splice variation; variation of expression, degradation and localization; down-regulation by atypical (decoy) receptors; interactions with cell-surface glycosaminoglycans; post-translational modifications; oligomerization; alternative signaling responses; and binding to natural or pharmacological inhibitors.
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Affiliation(s)
- Martin J Stone
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia.
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia.
| | - Jenni A Hayward
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia.
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia.
| | - Cheng Huang
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia.
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia.
| | - Zil E Huma
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia.
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia.
| | - Julie Sanchez
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia.
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia.
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14
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Zhang X, Kim KM. Multifactorial Regulation of G Protein-Coupled Receptor Endocytosis. Biomol Ther (Seoul) 2017; 25:26-43. [PMID: 28035080 PMCID: PMC5207461 DOI: 10.4062/biomolther.2016.186] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 11/21/2016] [Accepted: 11/30/2016] [Indexed: 12/26/2022] Open
Abstract
Endocytosis is a process by which cells absorb extracellular materials via the inward budding of vesicles formed from the plasma membrane. Receptor-mediated endocytosis is a highly selective process where receptors with specific binding sites for extracellular molecules internalize via vesicles. G protein-coupled receptors (GPCRs) are the largest single family of plasma-membrane receptors with more than 1000 family members. But the molecular mechanisms involved in the regulation of GPCRs are believed to be highly conserved. For example, receptor phosphorylation in collaboration with β-arrestins plays major roles in desensitization and endocytosis of most GPCRs. Nevertheless, a number of subsequent studies showed that GPCR regulation, such as that by endocytosis, occurs through various pathways with a multitude of cellular components and processes. This review focused on i) functional interactions between homologous and heterologous pathways, ii) methodologies applied for determining receptor endocytosis, iii) experimental tools to determine specific endocytic routes, iv) roles of small guanosine triphosphate-binding proteins in GPCR endocytosis, and v) role of post-translational modification of the receptors in endocytosis.
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Affiliation(s)
- Xiaohan Zhang
- Pharmacology Laboratory, College of Pharmacy, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Kyeong-Man Kim
- Pharmacology Laboratory, College of Pharmacy, Chonnam National University, Gwangju 61186, Republic of Korea
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15
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Marino KA, Prada-Gracia D, Provasi D, Filizola M. Impact of Lipid Composition and Receptor Conformation on the Spatio-temporal Organization of μ-Opioid Receptors in a Multi-component Plasma Membrane Model. PLoS Comput Biol 2016; 12:e1005240. [PMID: 27959924 PMCID: PMC5154498 DOI: 10.1371/journal.pcbi.1005240] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 11/07/2016] [Indexed: 11/21/2022] Open
Abstract
The lipid composition of cell membranes has increasingly been recognized as playing an important role in the function of various membrane proteins, including G Protein-Coupled Receptors (GPCRs). For instance, experimental and computational evidence has pointed to lipids influencing receptor oligomerization directly, by physically interacting with the receptor, and/or indirectly, by altering the bulk properties of the membrane. While the exact role of oligomerization in the function of class A GPCRs such as the μ-opioid receptor (MOR) is still unclear, insight as to how these receptors oligomerize and the relevance of the lipid environment to this phenomenon is crucial to our understanding of receptor function. To examine the effect of lipids and different MOR conformations on receptor oligomerization we carried out extensive coarse-grained molecular dynamics simulations of crystal structures of inactive and/or activated MOR embedded in an idealized mammalian plasma membrane composed of 63 lipid types asymmetrically distributed across the two leaflets. The results of these simulations point, for the first time, to specific direct and indirect effects of the lipids, as well as the receptor conformation, on the spatio-temporal organization of MOR in the plasma membrane. While sphingomyelin-rich, high-order lipid regions near certain transmembrane (TM) helices of MOR induce an effective long-range attractive force on individual protomers, both long-range lipid order and interface formation are found to be conformation dependent, with a larger number of different interfaces formed by inactive MOR compared to active MOR. The μ-opioid receptor (MOR) is an important pharmaceutical target in the treatment of pain. In order to develop novel pain therapies, devoid of the serious side-effects of present opioid analgesics, we need to understand the fundamentals of how MOR works on the molecular level. While some studies suggest that oligomers of MOR could play a role in signaling, how MOR forms dimers, which interfaces form, and the exact role of oligomers in MOR function remain unclear. While research has shown that the membrane environment can affect membrane protein function, most previous computational work to study oligomerization has been performed in a very simple membrane. Here, we use molecular dynamics simulations of MOR in a heterogeneous plasma membrane model (comprising 63 lipid types) to investigate how the presence of the protein modulates its lipid environment, affecting species distribution and sculpting characteristic order and thickness profiles around the receptors. Such modulations, in turn, induce long-range interactions between the proteins and favor the formation of specific dimeric conformations.
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Affiliation(s)
- Kristen A. Marino
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, United States of America
| | - Diego Prada-Gracia
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, United States of America
| | - Davide Provasi
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, United States of America
| | - Marta Filizola
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, United States of America
- * E-mail:
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16
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Dhopeshwarkar A, Mackie K. Functional Selectivity of CB2 Cannabinoid Receptor Ligands at a Canonical and Noncanonical Pathway. J Pharmacol Exp Ther 2016; 358:342-51. [PMID: 27194477 PMCID: PMC4959096 DOI: 10.1124/jpet.116.232561] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Accepted: 05/17/2016] [Indexed: 01/14/2023] Open
Abstract
The CB2 cannabinoid receptor (CB2) remains a tantalizing, but unrealized therapeutic target. CB2 receptor ligands belong to varied structural classes and display extreme functional selectivity. Here, we have screened diverse CB2 receptor ligands at canonical (inhibition of adenylyl cyclase) and noncanonical (arrestin recruitment) pathways. The nonclassic cannabinoid (-)-cis-3-[2-hydroxy-4-(1,1-dimethylheptyl)phenyl]-trans-4-(3-hydroxypropyl)cyclohexanol (CP55940) was the most potent agonist for both pathways, while the classic cannabinoid ligand (6aR,10aR)-3-(1,1-Dimethylbutyl)-6a,7,10,10a-tetrahydro-6,6,9-trimethyl-6H-dibenzo[b,d]pyran JWH133) was the most efficacious agonist among all the ligands profiled in cyclase assays. In the cyclase assay, other classic cannabinoids showed little [(-)-trans-Δ(9)-tetrahydrocannabinol and (-)-(6aR,7,10,10aR)-tetrahydro-6,6,9-trimethyl-3-(1-methyl-1-phenylethyl)-6H-dibenzo[b,d]pyran-1-ol] (KM233) to no efficacy [(6aR,10aR)-1-methoxy-6,6,9-trimethyl-3-(2-methyloctan-2-yl)-6a,7,10,10a-tetrahydrobenzo[c]chromene(L759633) and (6aR,10aR)-3-(1,1-dimethylheptyl)-6a,7,8,9,10,10a-hexahydro-1-methoxy-6,6-dimethyl-9-methylene-6H-dibenzo[b,d]pyran]L759656. Most aminoalkylindoles, including [(3R)-2,3-dihydro-5-methyl-3-(4-morpholinylmethyl)pyrrolo[1,2,3-de]-1,4-benzoxazin-6-yl]-1-naphthalenyl-methanone, monomethanesulfonate (WIN55212-2), were moderate efficacy agonists. The cannabilactone 3-(1,1-dimethyl-heptyl)-1-hydroxy-9-methoxy-benzo(c)chromen-6-one (AM1710) was equiefficacious to CP55940 to inhibit adenylyl cyclase, albeit with lower potency. In the arrestin recruitment assays, all classic cannabinoid ligands failed to recruit arrestins, indicating a bias toward G-protein coupling for this class of compound. All aminoalkylindoles tested, except for WIN55212-2 and (1-pentyl-1H-indol-3-yl)(2,2,3,3-tetramethylcyclopropyl)-methanone (UR144), failed to recruit arrestin. WIN55212-2 was a low efficacy agonist for arrestin recruitment, while UR144 was arrestin biased with no significant inhibition of cyclase. Endocannabinoids were G-protein biased with no arrestin recruitment. The diarylpyrazole antagonist 5-(4-chloro-3-methylphenyl)-1-[(4-methylphenyl)methyl]-N-[(1S,2S,4R)-1,3,3-trimethylbicyclo[2.2.1]hept-2-yl]-1H-pyrazole-3-carboxamide (SR144258) was an inverse agonist in cyclase and arrestin recruitment assays while the aminoalkylindole 6-iodo-2-methyl-1-[2-(4-morpholinyl)ethyl]-1H-indol-3-yl](4-methoxyphenyl)methanone (AM630) and carboxamide N-(1,3-benzodioxol-5-ylmethyl)-1,2-dihydro-7-methoxy-2-oxo-8-(pentyloxy)-3-quinolinecarboxamide (JTE907) were inverse agonists in cyclase but low efficacy agonists in arrestin recruitment assays. Thus, CB2 receptor ligands display strong and varied functional selectivity at both pathways. Therefore, extreme care must be exercised when using these compounds to infer the role of CB2 receptors in vivo.
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Affiliation(s)
- Amey Dhopeshwarkar
- The Gill Center for Biomolecular Science and the Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana
| | - Ken Mackie
- The Gill Center for Biomolecular Science and the Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana
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17
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Brejchova J, Vosahlikova M, Roubalova L, Parenti M, Mauri M, Chernyavskiy O, Svoboda P. Plasma membrane cholesterol level and agonist-induced internalization of δ-opioid receptors; colocalization study with intracellular membrane markers of Rab family. J Bioenerg Biomembr 2016; 48:375-96. [DOI: 10.1007/s10863-016-9667-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 06/02/2016] [Indexed: 10/21/2022]
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18
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Galandrin S, Onfroy L, Poirot MC, Sénard JM, Galés C. Delineating biased ligand efficacy at 7TM receptors from an experimental perspective. Int J Biochem Cell Biol 2016; 77:251-63. [PMID: 27107932 DOI: 10.1016/j.biocel.2016.04.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 04/15/2016] [Accepted: 04/16/2016] [Indexed: 12/17/2022]
Abstract
During the last 10 years, the concept of "biased agonism" also called "functional selectivity" swamped the pharmacology of 7 transmembrane receptors and paved the way for developing signaling pathway-selective drugs with increased efficacy and less adverse effects. Initially thought to select the activation of only a subset of the signaling pathways by the reference agonist, bias ligands revealed higher complexity as they have been shown to stabilize variable receptor conformations that associate with distinct signaling events from the reference. Today, one major challenge relies on the in vitro determination of the bias and classification of these ligands, as a prerequisite for future in vivo and clinical translation. In this review, current experimental considerations for the bias evaluation related to choice of the cellular model, of the signaling pathway as well as of the assays are presented and discussed.
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Affiliation(s)
- Ségolène Galandrin
- Institut des Maladies Métaboliques et Cardiovasculaires (I2MC), INSERM, UMR 1048, Université Toulouse, F-31432 Toulouse, France
| | - Lauriane Onfroy
- Institut des Maladies Métaboliques et Cardiovasculaires (I2MC), INSERM, UMR 1048, Université Toulouse, F-31432 Toulouse, France
| | - Mathias Charles Poirot
- Institut des Maladies Métaboliques et Cardiovasculaires (I2MC), INSERM, UMR 1048, Université Toulouse, F-31432 Toulouse, France
| | - Jean-Michel Sénard
- Institut des Maladies Métaboliques et Cardiovasculaires (I2MC), INSERM, UMR 1048, Université Toulouse, F-31432 Toulouse, France; Service de Pharmacologie Clinique, Faculté de médecine, Centre Hospitalier Universitaire de Toulouse, Université de Toulouse, F-31000 Toulouse, France
| | - Céline Galés
- Institut des Maladies Métaboliques et Cardiovasculaires (I2MC), INSERM, UMR 1048, Université Toulouse, F-31432 Toulouse, France.
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19
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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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Halls ML, Yeatman HR, Nowell CJ, Thompson GL, Gondin AB, Civciristov S, Bunnett NW, Lambert NA, Poole DP, Canals M. Plasma membrane localization of the μ-opioid receptor controls spatiotemporal signaling. Sci Signal 2016; 9:ra16. [PMID: 26861044 DOI: 10.1126/scisignal.aac9177] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Differential regulation of the μ-opioid receptor (MOR), a G protein (heterotrimeric guanine nucleotide-binding protein)-coupled receptor, contributes to the clinically limiting effects of opioid analgesics, such as morphine. We used biophysical approaches to quantify spatiotemporal MOR signaling in response to different ligands. In human embryonic kidney (HEK) 293 cells overexpressing MOR, morphine caused a Gβγ-dependent increase in plasma membrane-localized protein kinase C (PKC) activity, which resulted in a restricted distribution of MOR within the plasma membrane and induced sustained cytosolic extracellular signal-regulated kinase (ERK) signaling. In contrast, the synthetic opioid peptide DAMGO ([d-Ala(2),N-Me-Phe(4),Gly(5)-ol]-enkephalin) enabled receptor redistribution within the plasma membrane, resulting in transient increases in cytosolic and nuclear ERK activity, and, subsequently, receptor internalization. When Gβγ subunits or PKCα activity was inhibited or when the carboxyl-terminal phosphorylation sites of MOR were mutated, morphine-activated MOR was released from its restricted plasma membrane localization and stimulated a transient increase in cytosolic and nuclear ERK activity in the absence of receptor internalization. Thus, these data suggest that the ligand-induced redistribution of MOR within the plasma membrane, and not its internalization, controls its spatiotemporal signaling.
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Affiliation(s)
- Michelle L Halls
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia.
| | - Holly R Yeatman
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Cameron J Nowell
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Georgina L Thompson
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Arisbel Batista Gondin
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Srgjan Civciristov
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Nigel W Bunnett
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia. ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia. Department of Anesthesia and Perioperative Medicine, Monash University, Melbourne, Victoria 3004, Australia. Department of Pharmacology, The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Nevin A Lambert
- Department of Toxicology and Pharmacology, Georgia Regents University, Augusta, GA 30912, USA
| | - Daniel P Poole
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia. Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Meritxell Canals
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia. ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia.
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21
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Fitting S, Zou S, El-Hage N, Suzuki M, Paris JJ, Schier CJ, Rodríguez JW, Rodriguez M, Knapp PE, Hauser KF. Opiate addiction therapies and HIV-1 Tat: interactive effects on glial [Ca²⁺]i, oxyradical and neuroinflammatory chemokine production and correlative neurotoxicity. Curr HIV Res 2015; 12:424-34. [PMID: 25760046 PMCID: PMC4475822 DOI: 10.2174/1570162x1206150311161147] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2014] [Revised: 12/13/2014] [Accepted: 02/12/2015] [Indexed: 01/05/2023]
Abstract
Few preclinical studies have compared the relative therapeutic efficacy of medications used to treat opiate addiction in relation to neuroAIDS. Here we compare the ability of methadone and buprenorphine, and the prototypic opiate morphine, to potentiate the neurotoxic and proinflammatory ([Ca2+]i, ROS, H2O2, chemokines) effects of HIV-1 Tat in neuronal and/or mixed-glial co-cultures. Repeated observations of neurons during 48 h exposure to combinations of Tat, equimolar concentrations (500 nM) of morphine, methadone, or buprenorphine exacerbated neurotoxicity significantly above levels seen with Tat alone. Buprenorphine alone displayed marked neurotoxicity at 500 nM, prompting additional studies of its neurotoxic effects at 5 nM and 50 nM concentrations ± Tat. In combination with Tat, buprenorphine displayed paradoxical, concentration-dependent, neurotoxic and neuroprotective actions. Buprenorphine neurotoxicity coincided with marked elevations in [Ca2+]i, but not increases in glial ROS or chemokine release. Tat by itself elevated the production of CCL5/RANTES, CCL4/MIP-1β, and CCL2/MCP-1. Methadone and buprenorphine alone had no effect, but methadone interacted with Tat to further increase production of CCL5/RANTES. In combination with Tat, all drugs significantly increased glial [Ca2+]i, but ROS was only significantly increased by co-exposure with morphine. Taken together, the increases in glial [Ca2+]i, ROS, and neuroinflammatory chemokines were not especially accurate predictors of neurotoxicity. Despite similarities, opiates displayed differences in their neurotoxic and neuroinflammatory interactions with Tat. Buprenorphine, in particular, was partially neuroprotective at a low concentration, which may result from its unique pharmacological profile at multiple opioid receptors. Overall, the results reveal differences among addiction medications that may impact neuroAIDS.
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Xu C, Zhang Y, Zheng H, Loh HH, Law PY. Morphine modulates mouse hippocampal progenitor cell lineages by upregulating miR-181a level. Stem Cells 2015; 32:2961-72. [PMID: 24964978 DOI: 10.1002/stem.1774] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 05/19/2014] [Accepted: 05/23/2014] [Indexed: 12/20/2022]
Abstract
The mechanism by which addictive drugs such as morphine regulate adult neurogenesis remains elusive. We now demonstrate that morphine can regulate neurogenesis by control of miR-181a and subsequent hippocampal neural progenitor cell (hNPC) lineages. In the presence of morphine, hNPCs preferentially differentiated into astrocytes, an effect blocked by the specific μ-opioid receptor antagonist, Cys(2)-Tyr(3)-Orn(5)-Pen(7)-amide. This effect was mediated by the Prox1/Notch1 pathway as demonstrated by an increase in Notch1 level in the morphine- but not fentanyl-treated hNPCs and blocked by overexpression of Notch1 siRNA. Overexpression of Prox1 siRNA upregulated Notch1 level and potentiated the morphine-induced lineage changes. Prox1 transcript level was regulated by direct interaction between miR-181a and its 3'-UTR sequence. In vitro and in vivo treatment with morphine resulted in an increase in miR-181a level in hNPCs and mouse hippocampi, respectively. Overexpression of miR-181a mimics reduced Prox1 levels, increased Notch1 levels, and enhanced hNPCs differentiation into astrocytes. Meanwhile, overexpression of the miR-181a inhibitor raised Prox1 levels, decreased Notch1 levels, and subsequently blocked the morphine-induced lineage changes. Thus, by modulating Prox1/Notch1 activities via miR-181a, morphine influences the fate of differentiating hNPCs differentiation and therefore the ultimate quantities of mature neurons and astrocytes.
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Affiliation(s)
- Chi Xu
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
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Xu C, Zheng H, Loh HH, Law PY. Morphine Promotes Astrocyte-Preferential Differentiation of Mouse Hippocampal Progenitor Cells via PKCε-Dependent ERK Activation and TRBP Phosphorylation. Stem Cells 2015; 33:2762-72. [PMID: 26012717 DOI: 10.1002/stem.2055] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 05/12/2015] [Indexed: 01/24/2023]
Abstract
Previously we have shown that morphine regulates adult neurogenesis by modulating miR-181a maturation and subsequent hippocampal neural progenitor cell (NPC) lineages. Using NPCs cultured from PKCε or β-arrestin2 knockout mice and the MAPK/ERK kinase inhibitor U0126, we demonstrate that regulation of NPC differentiation via the miR-181a/Prox1/Notch1 pathway exhibits ligand-dependent selectivity. In NPCs, morphine and fentanyl activate ERK via the PKCε- and β-arrestin-dependent pathways, respectively. After fentanyl exposure, the activated phospho-ERK translocates to the nucleus. Conversely, after morphine treatment, phospho-ERK remains in the cytosol and is capable of phosphorylating TAR RNA-binding protein (TRBP), a cofactor of Dicer. This augments Dicer activity and promotes the maturation of miR-181a. Furthermore, using NPCs transfected with wild-type TRBP, SΔA, and SΔD TRBP mutants, we confirmed the crucial role of TRBP phosphorylation in Dicer activity, miR-181a maturation, and finally the morphine-induced astrocyte-preferential differentiation of NPCs. Thus, morphine modulates the lineage-specific differentiation of NPCs by PKCε-dependent ERK activation with subsequent TRBP phosphorylation and miR-181a maturation.
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Affiliation(s)
- Chi Xu
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Hui Zheng
- Stem Cell and Cancer Biology Group, Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, People's Republic of China
| | - Horace H Loh
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Ping-Yee Law
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
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Mudgal A, Pasha S. Role of opioid receptor heterodimerization in pain modulation and tolerance development. World J Pharmacol 2015; 4:144-159. [DOI: 10.5497/wjp.v4.i1.144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 10/09/2014] [Accepted: 02/11/2015] [Indexed: 02/06/2023] Open
Abstract
Protein to protein interactions leading to homo/heteromerization of receptor is well documented in literature. These interactions leading to dimeric/oligomers formation of receptors are known to modulate their function, particularly in case of G-protein coupled receptors. The opioid receptor heteromers having changed pharmacological properties than the constituent protomers provides preferences for novel drug targets that could lead to potential analgesic activity devoid of tolerance and physical dependence. Heterodimerization of opioid receptors appears to generate novel binding properties with improved specificity and lack of side effects. Further the molecules which can interact simultaneously to both the protomers of the heteromer, or to both the binding sites (orthosteric and allosteric) of a receptor protein could be potential therapeutic molecules. This review highlights the recent advancements in exploring the plausible role of heteromerization of opioid receptors in induction of tolerance free antinociception.
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Koole C, Wootten D, Simms J, Miller LJ, Christopoulos A, Sexton PM. Differential impact of amino acid substitutions on critical residues of the human glucagon-like peptide-1 receptor involved in peptide activity and small-molecule allostery. J Pharmacol Exp Ther 2015; 353:52-63. [PMID: 25630467 DOI: 10.1124/jpet.114.220913] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The glucagon-like peptide-1 receptor (GLP-1R) is a class B G protein-coupled receptor that has a critical role in the regulation of glucose homeostasis, principally through the regulation of insulin secretion. The receptor system is highly complex, able to be activated by both endogenous [GLP-1(1-36)NH2, GLP-1(1-37), GLP-1(7-36)NH2, GLP-1(7-37), oxyntomodulin], and exogenous (exendin-4) peptides in addition to small-molecule allosteric agonists (compound 2 [6,7-dichloro-2-methylsulfonyl-3-tert-butylaminoquinoxaline], BETP [4-(3-benzyloxy)phenyl)-2-ethylsulfinyl-6-(trifluoromethyl)pyrimidine]). Furthermore, the GLP-1R is subject to single-nucleotide polymorphic variance, resulting in amino acid changes in the receptor protein. In this study, we investigated two polymorphic variants previously reported to impact peptide-mediated receptor activity (M149) and small-molecule allostery (C333). These residues were mutated to a series of alternate amino acids, and their functionality was monitored across physiologically significant signaling pathways, including cAMP, extracellular signal-regulated kinase 1 and 2 phosphorylation, and intracellular Ca(2+) mobilization, in addition to peptide binding and cell-surface expression. We observed that residue 149 is highly sensitive to mutation, with almost all peptide responses significantly attenuated at mutated receptors. However, most reductions in activity were able to be restored by the small-molecule allosteric agonist compound 2. Conversely, mutation of residue 333 had little impact on peptide-mediated receptor activation, but this activity could not be modulated by compound 2 to the same extent as that observed at the wild-type receptor. These results provide insight into the importance of residues 149 and 333 in peptide function and highlight the complexities of allosteric modulation within this receptor system.
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Affiliation(s)
- Cassandra Koole
- Drug Discovery Biology Laboratory, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria, Australia (C.K., D.W., J.S., A.C., P.M.S.); and Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, Arizona (L.J.M.)
| | - Denise Wootten
- Drug Discovery Biology Laboratory, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria, Australia (C.K., D.W., J.S., A.C., P.M.S.); and Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, Arizona (L.J.M.)
| | - John Simms
- Drug Discovery Biology Laboratory, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria, Australia (C.K., D.W., J.S., A.C., P.M.S.); and Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, Arizona (L.J.M.)
| | - Laurence J Miller
- Drug Discovery Biology Laboratory, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria, Australia (C.K., D.W., J.S., A.C., P.M.S.); and Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, Arizona (L.J.M.)
| | - Arthur Christopoulos
- Drug Discovery Biology Laboratory, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria, Australia (C.K., D.W., J.S., A.C., P.M.S.); and Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, Arizona (L.J.M.)
| | - Patrick M Sexton
- Drug Discovery Biology Laboratory, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria, Australia (C.K., D.W., J.S., A.C., P.M.S.); and Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, Arizona (L.J.M.)
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Carayon K, Moulédous L, Combedazou A, Mazères S, Haanappel E, Salomé L, Mollereau C. Heterologous regulation of Mu-opioid (MOP) receptor mobility in the membrane of SH-SY5Y cells. J Biol Chem 2014; 289:28697-706. [PMID: 25183007 DOI: 10.1074/jbc.m114.588558] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The dynamic organization of G protein-coupled receptors in the plasma membrane is suspected of playing a role in their function. The regulation of the diffusion mode of the mu-opioid (MOP) receptor was previously shown to be agonist-specific. Here we investigate the regulation of MOP receptor diffusion by heterologous activation of other G protein-coupled receptors and characterize the dynamic properties of the MOP receptor within the heterodimer MOP/neuropeptide FF (NPFF2) receptor. The data show that the dynamics and signaling of the MOP receptor in SH-SY5Y cells are modified by the activation of α2-adrenergic and NPFF2 receptors, but not by the activation of receptors not described to interact with the opioid receptor. By combining, for the first time, fluorescence recovery after photobleaching at variable radius experiments with bimolecular fluorescence complementation, we show that the MOP/NPFF2 heterodimer adopts a specific diffusion behavior that corresponds to a mix of the dynamic properties of both MOP and NPFF2 receptors. Altogether, the data suggest that heterologous regulation is accompanied by a specific organization of receptors in the membrane.
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Affiliation(s)
- Kévin Carayon
- From the Institut de Pharmacologie et Biologie Structurale, UMR5089 CNRS/Université de Toulouse, 31077 Toulouse, France
| | - Lionel Moulédous
- From the Institut de Pharmacologie et Biologie Structurale, UMR5089 CNRS/Université de Toulouse, 31077 Toulouse, France
| | - Anne Combedazou
- From the Institut de Pharmacologie et Biologie Structurale, UMR5089 CNRS/Université de Toulouse, 31077 Toulouse, France
| | - Serge Mazères
- From the Institut de Pharmacologie et Biologie Structurale, UMR5089 CNRS/Université de Toulouse, 31077 Toulouse, France
| | - Evert Haanappel
- From the Institut de Pharmacologie et Biologie Structurale, UMR5089 CNRS/Université de Toulouse, 31077 Toulouse, France
| | - Laurence Salomé
- From the Institut de Pharmacologie et Biologie Structurale, UMR5089 CNRS/Université de Toulouse, 31077 Toulouse, France
| | - Catherine Mollereau
- From the Institut de Pharmacologie et Biologie Structurale, UMR5089 CNRS/Université de Toulouse, 31077 Toulouse, France
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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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Macey TA, Bobeck EN, Suchland KL, Morgan MM, Ingram SL. Change in functional selectivity of morphine with the development of antinociceptive tolerance. Br J Pharmacol 2014; 172:549-61. [PMID: 24666417 DOI: 10.1111/bph.12703] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 03/14/2014] [Accepted: 03/18/2014] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND AND PURPOSE Opioids, such as morphine, are the most effective treatment for pain but their efficacy is diminished with the development of tolerance following repeated administration. Recently, we found that morphine activated ERK in opioid-tolerant but not in naïve rats, suggesting that morphine activation of μ-opioid receptors is altered following repeated morphine administration. Here, we have tested the hypothesis that μ-opioid receptor activation of ERK in the ventrolateral periaqueductal gray (vlPAG) is dependent on dynamin, a protein implicated in receptor endocytosis. EXPERIMENTAL APPROACH Rats were made tolerant to repeated microinjections of morphine into the vlPAG. The effects of dynamin on ERK activation and antinociception were assessed by microinjecting myristoylated dominant-negative dynamin peptide (Dyn-DN) or a scrambled control peptide into the vlPAG. Microinjection of a fluorescent dermorphin analogue (DERM-A594) into the vlPAG was used to monitor μ-opioid receptor internalization. KEY RESULTS Morphine did not activate ERK and Dyn-DN administration had no effect on morphine-induced antinociception in saline-pretreated rats. In contrast, morphine-induced ERK activation in morphine-pretreated rats that was blocked by Dyn-DN administration. Dyn-DN also inhibited morphine antinociception. Finally, morphine reduced DERM-A594 internalization only in morphine-tolerant rats indicating that μ-opioid receptors were internalized and unavailable to bind DERM-A594. CONCLUSIONS AND IMPLICATIONS Repeated morphine administration increased μ-opioid receptor activation of ERK signalling via a dynamin-dependent mechanism. These results demonstrate that the balance of agonist signalling to G-protein and dynamin-dependent pathways is altered, effectively changing the functional selectivity of the agonist-receptor complex. LINKED ARTICLES This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2.
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Affiliation(s)
- T A Macey
- Department of Neurological Surgery, Oregon Health & Science University, Portland, OR, USA
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29
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Xu C, Zhang W, Rondard P, Pin JP, Liu J. Complex GABAB receptor complexes: how to generate multiple functionally distinct units from a single receptor. Front Pharmacol 2014; 5:12. [PMID: 24575041 PMCID: PMC3920572 DOI: 10.3389/fphar.2014.00012] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Accepted: 01/22/2014] [Indexed: 01/05/2023] Open
Abstract
The main inhibitory neurotransmitter, GABA, acts on both ligand-gated and G protein-coupled receptors, the GABAA/C and GABAB receptors, respectively. The later play important roles in modulating many synapses, both at the pre- and post-synaptic levels, and are then still considered as interesting targets to treat a number of brain diseases, including addiction. For many years, several subtypes of GABAB receptors were expected, but cloning revealed only two genes that work in concert to generate a single type of GABAB receptor composed of two subunits. Here we will show that the signaling complexity of this unit receptor type can be largely increased through various ways, including receptor stoichiometry, subunit isoforms, cell-surface expression and localization, crosstalk with other receptors, or interacting proteins. These recent data revealed how complexity of a receptor unit can be increased, observation that certainly are not unique to the GABAB receptor.
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Affiliation(s)
- Chanjuan Xu
- Cellular Signaling Laboratory, Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology Wuhan, China
| | - Wenhua Zhang
- Cellular Signaling Laboratory, Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology Wuhan, China
| | - Philippe Rondard
- Institut de Génomique Fonctionnelle, CNRS UMR5203, INSERM U661, Universités de Montpellier I & II Montpellier, France
| | - Jean-Philippe Pin
- Institut de Génomique Fonctionnelle, CNRS UMR5203, INSERM U661, Universités de Montpellier I & II Montpellier, France
| | - Jianfeng Liu
- Cellular Signaling Laboratory, Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology Wuhan, China
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Qiu Y, Zhao W, Wang Y, Xu JR, Huie E, Jiang S, Yan YH, Loh HH, Chen HZ, Law PY. FK506-binding protein 12 modulates μ-opioid receptor phosphorylation and protein kinase C(ε)-dependent signaling by its direct interaction with the receptor. Mol Pharmacol 2013; 85:37-49. [PMID: 24113748 DOI: 10.1124/mol.113.087825] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Protein kinase C (PKC) activation plays an important role in morphine-induced μ-opioid receptor (OPRM1) desensitization and tolerance development. It was recently shown that receptor phosphorylation by G protein-coupled receptor kinase regulates agonist-dependent selective signaling and that inefficient phosphorylation of OPRM1 leads to PKCε activation and subsequent responses. Here, we demonstrate that such receptor phosphorylation and PKCε activation can be modulated by FK506-binding protein 12 (FKBP12). Using a yeast two-hybrid screen, FKBP12 was identified as specifically interacting with OPRM1 at the Pro(353) residue. In human embryonic kidney 293 cells expressing OPRM1, the association of FKBP12 with OPRM1 decreased the agonist-induced receptor phosphorylation at Ser(375). The morphine-induced PKCε activation and the recruitment of PKCε to the OPRM1 signaling complex were attenuated both by FKBP12 short interfering RNA (siRNA) treatment and in cells expressing OPRM1 with a P353A mutation (OPRM1P353A), which leads to diminished activation of PKC-dependent extracellular signal-regulated kinases. Meanwhile, the overexpression of FKBP12 enabled etorphine to activate PKCε. Further analysis of the receptor complex demonstrated that morphine treatment enhanced the association of FKBP12 and calcineurin with the receptor. The blockade of the FKBP12 association with the receptor by the siRNA-mediated knockdown of endogenous FKBP12 or the mutation of Pro(353) to Ala resulted in a reduction in PKCε and calcineurin recruitment to the receptor signaling complex. The receptor-associated calcineurin modulates OPRM1 phosphorylation, as demonstrated by the ability of the calcineurin autoinhibitory peptide to increase the receptor phosphorylation. Thus, the association of FKBP12 with OPRM1 attenuates the phosphorylation of the receptor and triggers the recruitment and activation of PKCε.
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Affiliation(s)
- Yu Qiu
- Department of Pharmacology, Institute of Medical Sciences, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China (Y.Q., Y.W., J.-R.X., S.J., Y.-H.Y., H.-Z.C.); and Department of Pharmacology, University of Minnesota, Minneapolis, Minnesota (Y.Q., W.Z., E.H., H.H.L., P.-Y.L.)
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Kumari R, Castillo C, Francesconi A. Agonist-dependent signaling by group I metabotropic glutamate receptors is regulated by association with lipid domains. J Biol Chem 2013; 288:32004-19. [PMID: 24045944 DOI: 10.1074/jbc.m113.475863] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Group I metabotropic glutamate receptors (mGluRs), mGluR1 and mGluR5, play critical functions in forms of activity-dependent synaptic plasticity and synapse remodeling in physiological and pathological states. Importantly, in animal models of fragile X syndrome, group I mGluR activity is abnormally enhanced, a dysfunction that may partly underlie cognitive deficits in the condition. Lipid rafts are cholesterol- and sphingolipid-enriched membrane domains that are thought to form transient signaling platforms for ligand-activated receptors. Many G protein-coupled receptors, including group I mGluRs, are present in lipid rafts, but the mechanisms underlying recruitment to these membrane domains remain incompletely understood. Here, we show that mGluR1 recruitment to lipid rafts is enhanced by agonist binding and is supported at least in part by an intact cholesterol recognition/interaction amino acid consensus (CRAC) motif in the receptor. Substitutions of critical residues in the motif reduce mGluR1 association with lipid rafts and agonist-induced, mGluR1-dependent activation of extracellular-signal-activated kinase1/2 MAP kinase (ERK-MAPK). We find that alteration of membrane cholesterol content or perturbation of lipid rafts regulates agonist-dependent activation of ERK-MAPK by group I mGluRs, suggesting a potential function for cholesterol as a positive allosteric modulator of receptor function(s). Together, these findings suggest that drugs that alter membrane cholesterol levels or directed to the receptor-cholesterol interface could be employed to modulate abnormal group I mGluR activity in neuropsychiatric conditions, including fragile X syndrome.
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Affiliation(s)
- Ranju Kumari
- From the Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York 10461
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32
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Börner C, Lanciotti S, Koch T, Höllt V, Kraus J. μ opioid receptor agonist-selective regulation of interleukin-4 in T lymphocytes. J Neuroimmunol 2013; 263:35-42. [PMID: 23965172 DOI: 10.1016/j.jneuroim.2013.07.012] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Revised: 07/08/2013] [Accepted: 07/18/2013] [Indexed: 12/13/2022]
Abstract
Opioids are irreplaceable for the treatment of severe pain. However, opioid-induced immunomodulation affects therapies. Here we report that treatment of human T lymphocytes with the opioids fentanyl, methadone, loperamide and beta-endorphin resulted in a strong induction of the cytokine interleukin-4. In contrast, morphine and buprenorphine induced markedly and significantly lower levels of interleukin-4 mRNA and protein. These findings suggest agonist-biased μ opioid receptor signaling in T cells. In the future, better knowledge about agonist-specific immunomodulatory effects of opioids offers the possibility to select drugs for a therapy with more favorable and/or less detrimental side effects in immune cells.
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Affiliation(s)
- Christine Börner
- Department of Pharmacology and Toxicology, University of Magdeburg, 44 Leipzigerstrasse, 39120 Magdeburg, Germany
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Law PY, Reggio PH, Loh HH. Opioid receptors: toward separation of analgesic from undesirable effects. Trends Biochem Sci 2013; 38:275-82. [PMID: 23598157 DOI: 10.1016/j.tibs.2013.03.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Revised: 03/06/2013] [Accepted: 03/11/2013] [Indexed: 12/21/2022]
Abstract
The use of opioid analgesics for pain has always been hampered by their many side effects; in particular, the addictive liability associated with chronic use. Recently, attempts to develop analgesic agents with reduced side effects have targeted either the putative opioid receptor splice variants or the receptor hetero-oligomers. This review discusses the potential for receptor splice variant- and the hetero-oligomer-based discovery of new opioid analgesics. We also examine an alternative approach of using receptor mutants for pain management. Finally, we discuss the role of the biased agonism observed and the recently reported opioid receptor crystal structures in guiding the future development of opioid analgesics.
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Affiliation(s)
- Ping-Yee Law
- Department of Pharmacology, University of Minnesota, Medical School, Minneapolis, MN 55455, USA.
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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: 585] [Impact Index Per Article: 53.2] [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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35
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Zheng H, Loh HH, Law PY. Posttranslation modification of G protein-coupled receptor in relationship to biased agonism. Methods Enzymol 2013; 522:391-408. [PMID: 23374194 DOI: 10.1016/b978-0-12-407865-9.00018-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Biased signaling has been reported with a series of G protein-coupled receptors (GPCRs), including β(2)-adrenergic receptor and μ-opioid receptor (OPRM1). The concept of biased signaling suggests that the agonists of one particular receptor may activate the downstream signaling pathways with different efficacies. Thus in an extreme case, agonists might activate different sets of signaling pathways, which provide a new route to develop drugs with increased efficacies and decreased side effects. Among the many factors, posttranslation modifications of receptor proteins have major roles in influencing the biased signaling. Take OPRM1, for example, the phosphorylation and palmitoylation of receptor can regulate the biased signaling induced by agonists. Thus, by modulating these posttranslation modifications, the biased signaling of GPCRs can be regulated. In addition, although it is not considered as posttranslation modification normally, the distribution of GPCRs on cell membrane, especially the distribution between lipid-raft and non-raft microdomains, also contributes to the biased signaling. Thus in this chapter, we described the methods used in our laboratory to study receptor phosphorylation, receptor palmitoylation, and membrane distribution of receptor by using OPRM1 as a model. A functional model was also provided on these posttranslational modifications at the last section of this chapter.
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Affiliation(s)
- Hui Zheng
- Stem Cell and Cancer Biology Group, Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China.
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36
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Calizo RC, Scarlata S. A role for G-proteins in directing G-protein-coupled receptor-caveolae localization. Biochemistry 2012; 51:9513-23. [PMID: 23102276 PMCID: PMC3507317 DOI: 10.1021/bi301107p] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Caveolae are membrane domains that may influence cell
signaling
by sequestering specific proteins such as G-protein-coupled receptors
(GPCRs). While previous reports largely show that Gαq subunits, but not other G-proteins, interact strongly with the caveolae
protein, Caveolin-1 (Cav1), the inclusion of GPCRs in caveolae is
controversial. Here, we have used fluorescence methods to determine
the effect of caveolae on the physical and functional properties of
two GPCRs that have been reported to reside in caveolae, bradykinin
receptor type 2 (B2R), which is coupled to Gαq, and the μ-opioid receptor (μOR), which is coupled
to Gαi. While caveolae do not affect cAMP signals
mediated by μOR, they prolong Ca2+ signals mediated
by B2R. In A10 cells that endogenously express B2R and Cav1, downregulation of Cav1 ablates the prolonged recovery
seen upon bradykinin stimulation in accord with the idea that the
presence of caveolae prolongs Gαq activation. Immunofluorescence
and Förster resonance energy transfer (FRET) studies show that
a significant fraction of B2R resides at or close to caveolae
domains while none or very little μOR resides in caveolae domains.
The level of FRET between B2R and caveolae is reduced by
downregulation of Gαq or by addition of a peptide
that interferes with Gαq–Caveolin-1 interactions,
suggesting that Gαq promotes localization of B2R to caveolae domains. Our results lead to the suggestion
that Gαq can localize its associated receptors to
caveolae domains to enhance their signals.
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Affiliation(s)
- Rhodora Cristina Calizo
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY 11794-8661, USA
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37
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Canto I, Soh UJK, Trejo J. Allosteric modulation of protease-activated receptor signaling. Mini Rev Med Chem 2012; 12:804-11. [PMID: 22681248 DOI: 10.2174/138955712800959116] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2011] [Revised: 08/17/2011] [Accepted: 09/02/2011] [Indexed: 12/23/2022]
Abstract
The protease-activated receptors (PARs) are G protein-coupled receptors (GPCRs) that are uniquely activated by proteolysis. PARs mediate hemostasis, thrombosis, inflammation, embryonic development and progression of certain malignant cancers. The family of PARs include four members: PAR1, PAR2, PAR3 and PAR4. PARs harbor a cryptic ligand sequence within their N-terminus that is exposed following proteolytic cleavage. The newly formed PAR Nterminus functions as a tethered ligand that binds intramolecularly to the receptor to trigger transmembrane signaling. This unique mechanism of activation would indicate that regardless of the activating protease, cleavage of PARs would unmask a tethered ligand sequence that would induce a similar active receptor conformation and signaling response. However, this is not the case. Recent studies demonstrate that PARs can be differentially activated by synthetic peptide agonists, proteases or through dimerization, that ultimately result in distinct cellular responses. In some cases, allosteric modulation of PARs involves compartmentalization in caveolae, plasma membrane microdomains enriched in cholesterol. Here, we discuss some mechanisms that lead to allosteric modulation of PAR signaling.
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Affiliation(s)
- I Canto
- Department of Pharmacology, School of Medicine, University of California, San Diego, Biomedical Sciences Building, Room 3044A, 9500 Gilman Drive, La Jolla, CA 92093-0636, USA.
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González-Maeso J, Sealfon SC. Functional selectivity in GPCR heterocomplexes. Mini Rev Med Chem 2012; 12:851-5. [PMID: 22681249 DOI: 10.2174/138955712800959152] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Revised: 09/06/2011] [Accepted: 09/09/2011] [Indexed: 01/15/2023]
Abstract
G protein-coupled receptors (GPCRs) can couple to more than one signaling pathway. Biophysical studies and pharmacological theory indicate that they exist in different active conformations that differ in their capacity to activate specific signaling pathways. Individual agonists stabilize particular active conformations and thereby can differ in their relative activation of different signaling pathways coupled to the same receptor, a phenomenon referred to as functional selectivity. Many pairs of GPCRs have been shown to interact and form heterocomplexes in vitro and in vivo. Recent studies implicate these complexes in the responses to some therapeutic drugs and drugs of abuse, and raise the possibility that they may be involved in mediating functional selectivity.
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Affiliation(s)
- J González-Maeso
- Department Psychiatry, Mount Sinai School of Medicine, New York, New York, USA
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39
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Dang VC, Christie MJ. Mechanisms of rapid opioid receptor desensitization, resensitization and tolerance in brain neurons. Br J Pharmacol 2012; 165:1704-1716. [PMID: 21564086 DOI: 10.1111/j.1476-5381.2011.01482.x] [Citation(s) in RCA: 126] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Agonists acting on µ-opioid receptors (MOR) are very effective analgesics but cause tolerance during long-term or repeated exposure. Intensive efforts have been made to find novel opioid agonists that are efficacious analgesics but can elude the signalling events that cause tolerance. µ-Opioid agonists differentially couple to downstream signalling mechanisms. Some agonists, such as enkephalins, D-Ala(2),N-Me-Phe(4),Gly(5)-ol]-enkephalin (DAMGO), methadone and sufentanyl are efficacious at mediating G-protein and effector coupling, as well as triggering MOR regulatory events that include MOR phosphorylation, β-arrestin binding, receptor endocytosis and recycling. By contrast, morphine and closely related alkaloids can mediate efficacious MOR-effector coupling but poorly trigger receptor regulation. Several models have been proposed to relate differential MOR regulation by different opioids with their propensity to cause tolerance. Most are based on dogma that β-arrestin-2 (βarr-2) binding causes MOR desensitization and/or that MOR endocytosis and recycling are required for receptor resensitization. This review will examine some of these notions in light of recent evidence establishing that MOR dephosphorylation and resensitization do not require endocytosis. Recent evidence from opioid-treated animals also suggests that impaired MOR-effector coupling is driven, at least in part, by enhanced desensitization, as well as impaired resensitization that appears to be βarr-2 dependent. Better understanding of how chronic exposure to opioids alters receptor regulatory mechanisms may facilitate the development of effective analgesics that produce limited tolerance.
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Affiliation(s)
- Vu C Dang
- Department of Psychiatry, University of California, San Francisco, CA, USABrain & Mind Research Institute, University of Sydney, NSW, Australia
| | - MacDonald J Christie
- Department of Psychiatry, University of California, San Francisco, CA, USABrain & Mind Research Institute, University of Sydney, NSW, Australia
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40
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Wilson RL, Frisz JF, Hanafin WP, Carpenter KJ, Hutcheon ID, Weber PK, Kraft ML. Fluorinated colloidal gold immunolabels for imaging select proteins in parallel with lipids using high-resolution secondary ion mass spectrometry. Bioconjug Chem 2012; 23:450-60. [PMID: 22284327 PMCID: PMC3951754 DOI: 10.1021/bc200482z] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The local abundance of specific lipid species near a membrane protein is hypothesized to influence the protein's activity. The ability to simultaneously image the distributions of specific protein and lipid species in the cell membrane would facilitate testing these hypotheses. Recent advances in imaging the distribution of cell membrane lipids with mass spectrometry have created the desire for membrane protein probes that can be simultaneously imaged with isotope labeled lipids. Such probes would enable conclusive tests to determine whether specific proteins colocalize with particular lipid species. Here, we describe the development of fluorine-functionalized colloidal gold immunolabels that facilitate the detection and imaging of specific proteins in parallel with lipids in the plasma membrane using high-resolution SIMS performed with a NanoSIMS. First, we developed a method to functionalize colloidal gold nanoparticles with a partially fluorinated mixed monolayer that permitted NanoSIMS detection and rendered the functionalized nanoparticles dispersible in aqueous buffer. Then, to allow for selective protein labeling, we attached the fluorinated colloidal gold nanoparticles to the nonbinding portion of antibodies. By combining these functionalized immunolabels with metabolic incorporation of stable isotopes, we demonstrate that influenza hemagglutinin and cellular lipids can be imaged in parallel using NanoSIMS. These labels enable a general approach to simultaneously imaging specific proteins and lipids with high sensitivity and lateral resolution, which may be used to evaluate predictions of protein colocalization with specific lipid species.
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Affiliation(s)
- Robert L. Wilson
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801
| | - Jessica F. Frisz
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801
| | - William P. Hanafin
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801
| | - Kevin J. Carpenter
- Glenn Seaborg Institute, Lawrence Livermore National Laboratory, Livermore, CA 94551
| | - Ian D. Hutcheon
- Glenn Seaborg Institute, Lawrence Livermore National Laboratory, Livermore, CA 94551
| | - Peter K. Weber
- Glenn Seaborg Institute, Lawrence Livermore National Laboratory, Livermore, CA 94551
| | - Mary L. Kraft
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801
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41
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Zheng H, Pearsall EA, Hurst DP, Zhang Y, Chu J, Zhou Y, Reggio PH, Loh HH, Law PY. Palmitoylation and membrane cholesterol stabilize μ-opioid receptor homodimerization and G protein coupling. BMC Cell Biol 2012; 13:6. [PMID: 22429589 PMCID: PMC3317874 DOI: 10.1186/1471-2121-13-6] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2011] [Accepted: 03/19/2012] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND A cholesterol-palmitoyl interaction has been reported to occur in the dimeric interface of the β₂-adrenergic receptor crystal structure. We sought to investigate whether a similar phenomenon could be observed with μ-opioid receptor (OPRM1), and if so, to assess the role of cholesterol in this class of G protein-coupled receptor (GPCR) signaling. RESULTS C3.55(170) was determined to be the palmitoylation site of OPRM1. Mutation of this Cys to Ala did not affect the binding of agonists, but attenuated receptor signaling and decreased cholesterol associated with the receptor signaling complex. In addition, both attenuation of receptor palmitoylation (by mutation of C3.55[170] to Ala) and inhibition of cholesterol synthesis (by treating the cells with simvastatin, a HMG-CoA reductase inhibitor) impaired receptor signaling, possibly by decreasing receptor homodimerization and Gαi2 coupling; this was demonstrated by co-immunoprecipitation, immunofluorescence colocalization and fluorescence resonance energy transfer (FRET) analyses. A computational model of the OPRM1 homodimer structure indicated that a specific cholesterol-palmitoyl interaction can facilitate OPRM1 homodimerization at the TMH4-TMH4 interface. CONCLUSIONS We demonstrate that C3.55(170) is the palmitoylation site of OPRM1 and identify a cholesterol-palmitoyl interaction in the OPRM1 complex. Our findings suggest that this interaction contributes to OPRM1 signaling by facilitating receptor homodimerization and G protein coupling. This conclusion is supported by computational modeling of the OPRM1 homodimer.
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Affiliation(s)
- Hui Zheng
- Department of Pharmacology, University of Minnesota, Minneapolis, Minnesota 55455, USA.
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42
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Zheng H, Zou H, Liu X, Chu J, Zhou Y, Loh HH, Law PY. Cholesterol level influences opioid signaling in cell models and analgesia in mice and humans. J Lipid Res 2012; 53:1153-62. [PMID: 22377533 DOI: 10.1194/jlr.m024455] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cholesterol regulates the signaling of µ-opioid receptor in cell models, but it has not been demonstrated in mice or humans. Whether cholesterol regulates the signaling by mechanisms other than supporting the entirety of lipid raft microdomains is still unknown. By modulating cholesterol-enriched lipid raft microdomains and/or total cellular cholesterol contents in human embryonic kidney cells stably expressing µ-opioid receptor, we concluded that cholesterol stabilized opioid signaling both by supporting the lipid raft's entirety and by facilitating G protein coupling. Similar phenomena were observed in the primary rat hippocampal neurons. In addition, reducing the brain cholesterol level with simvastatin impaired the analgesic effect of opioids in mice, whereas the opioid analgesic effect was enhanced in mice fed a high-cholesterol diet. Furthermore, when the records of patients were analyzed, an inverse correlation between cholesterol levels and fentanyl doses used for anesthesia was identified, which suggested the mechanisms above could also be applicable to humans. Our results identified the interaction between opioids and cholesterol, which should be considered in clinics as a probable route for drug-drug interaction. Our studies also suggested that a low cholesterol level could lead to clinical issues, such as the observed impairment in opioid functions.
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Affiliation(s)
- Hui Zheng
- Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China.
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43
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Abstract
Dynamic changes in somatosensory perception occur as a result of multiple signaling events. In many instances, over-activation of sensory receptors results in the desensitization and subsequent increased threshold for activation of receptors. In other cases, receptor sensitization can occur following tissue injury and/or inflammation. In both cases, signaling mechanisms that control alterations in receptor activities can significantly affect organism response to sensory stimuli, including thermal, mechanical, and chemical. Due to the homeostatic nature of somatosensory recognition, dynamic changes in receptor response can negatively affect an individual's way of life, as well as alert individuals to tissue damage. Here, we will focus on scaffolding structures that regulate somatosensory neuronal excitability.
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Affiliation(s)
- Nathaniel A Jeske
- Departments of Oral and Maxillofacial Surgery, Pharmacology, University of Texas Health Science Center at San Antonio TX, USA
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44
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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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Gruol DL, Nelson TE, Hao C, Michael S, Vukojevic V, Ming Y, Terenius L. Ethanol alters opioid regulation of Ca(2+) influx through L-type Ca(2+) channels in PC12 cells. Alcohol Clin Exp Res 2011; 36:443-56. [PMID: 22014285 DOI: 10.1111/j.1530-0277.2011.01631.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Studies at the behavioral and synaptic level show that effects of ethanol on the central nervous system can involve the opioid signaling system. These interactions may alter the function of a common downstream target. In this study, we examined Ca(2+) channel function as a potential downstream target of interactions between ethanol and μ or κ opioid receptor signaling. METHODS The studies were carried out in a model system, undifferentiated PC12 cells transfected with μ or κ opioid receptors. The PC12 cells express L-type Ca(2+) channels, which were activated by K(+) depolarization. Ca(2+) imaging was used to measure relative Ca(2+) flux during K(+) depolarization and the modulation of Ca(2+) flux by opioids and ethanol. RESULTS Ethanol, μ receptor activation, and κ receptor activation all reduced the amplitude of the Ca(2+) signal produced by K(+) depolarization. Pretreatment with ethanol or combined treatment with ethanol and μ or κ receptor agonists caused a reduction in the amplitude of the Ca(2+) signal that was comparable to or smaller than that observed for the individual drugs alone, indicating an interaction by the drugs at a downstream target (or targets) that limited the modulation of Ca(2+) flux through L-type Ca(2+) channels. CONCLUSIONS These studies provide evidence for a cellular mechanism that could play an important role in ethanol regulation of synaptic transmission and behavior through interactions with the opioid signaling.
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Affiliation(s)
- Donna L Gruol
- Molecular and Integrative Neurosciences Department, The Scripps Research Institute, La Jolla, California 92037, USA
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48
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Abstract
Ketamine, a clinically relevant drug, has been shown to enhance opioid-induced analgesia and prevent hyperalgesia. However, the molecular mechanisms involved are not clearly understood. As previous studies found that activation of opioid receptors leads to the phosphorylation of mitogen-activated protein kinases, we investigated whether ketamine could modulate μ-opioid receptor (μOR)-mediated ERK1/2 phosphorylation. We find that acute treatment with ketamine enhances (∼2- to 3-fold) the levels of opioid-induced ERK1/2 phosphorylation in recombinant as well as cells endogenously expressing μOR. Interestingly, we find that in the absence of ketamine ERK1/2 signaling is desensitized 10 min after opioid exposure whereas in its presence significant levels (∼3-fold over basal) are detected. In addition, ketamine increases the rate of resensitization of opioid-mediated ERK1/2 signaling (15 min in its presence vs. 30 min in its absence). These results suggest that ketamine increases the effectiveness of opiate-induced signaling by affecting multiple mechanisms. In addition, these effects are observed in heterologous cells expressing μOR suggesting a non-NMDA receptor-mediated action of ketamine. Together this could, in part, account for the observed effects of ketamine on the enhancement of the analgesic effects of opiates as well as in the duration of opiate-induced analgesia.
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Affiliation(s)
- Achla Gupta
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, New York, New York, USA
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49
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Raehal KM, Schmid CL, Groer CE, Bohn LM. Functional selectivity at the μ-opioid receptor: implications for understanding opioid analgesia and tolerance. Pharmacol Rev 2011; 63:1001-19. [PMID: 21873412 DOI: 10.1124/pr.111.004598] [Citation(s) in RCA: 197] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Opioids are the most effective analgesic drugs for the management of moderate or severe pain, yet their clinical use is often limited because of the onset of adverse side effects. Drugs in this class produce most of their physiological effects through activation of the μ opioid receptor; however, an increasing number of studies demonstrate that different opioids, while presumably acting at this single receptor, can activate distinct downstream responses, a phenomenon termed functional selectivity. Functional selectivity of receptor-mediated events can manifest as a function of the drug used, the cellular or neuronal environment examined, or the signaling or behavioral measure recorded. This review summarizes both in vitro and in vivo work demonstrating functional selectivity at the μ opioid receptor in terms of G protein coupling, receptor phosphorylation, interactions with β-arrestins, receptor desensitization, internalization and signaling, and details on how these differences may relate to the progression of analgesic tolerance after their extended use.
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Affiliation(s)
- Kirsten M Raehal
- Molecular Therapeutics and Neuroscience, The Scripps Research Institute, Jupiter, Florida, USA
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50
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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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