1
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Placzek MS. Imaging Kappa Opioid Receptors in the Living Brain with Positron Emission Tomography. Handb Exp Pharmacol 2021; 271:547-577. [PMID: 34363128 DOI: 10.1007/164_2021_498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Kappa opioid receptor (KOR) neuroimaging using positron emission tomography (PET) has been immensely successful in all phases of discovery and validation in relation to radiotracer development from preclinical imaging to human imaging. There are now several KOR-specific PET radiotracers that can be utilized for neuroimaging, including agonist and antagonist ligands, as well as C-11 and F-18 variants. These technologies will increase KOR PET utilization by imaging centers around the world and have provided a foundation for future studies. In this chapter, I review the advances in KOR radiotracer discovery, focusing on ligands that have been translated into human imaging, and highlight key attributes unique to each KOR PET radiotracer. The utilization of these radiotracers in KOR PET neuroimaging can be subdivided into three major investigational classes: the first, measurement of KOR density; the second, measurement of KOR drug occupancy; the third, detecting changes in endogenous dynorphin following activation or deactivation. Given the involvement of the KOR/dynorphin system in a number of brain disorders including, but not limited to, pain, itch, mood disorders and addiction, measuring KOR density in the living brain will offer insight into the chronic effects of these disorders on KOR tone in humans. Notably, KOR PET has been successful at measuring drug occupancy in the human brain to guide dose selection for maximal therapeutic efficacy while avoiding harmful side effects. Lastly, we discuss the potential of KOR PET to detect changes in endogenous dynorphin in the human brain, to elucidate neural mechanisms and offer critical insight into disease-modifying therapeutics. We conclude with comments on other translational neuroimaging modalities such as MRI that could be used to study KOR-dynorphin tone in the living human brain.
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Affiliation(s)
- Michael S Placzek
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA. .,Department of Radiology, Harvard Medical School, Boston, MA, USA.
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2
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D'Elia A, Schiavi S, Soluri A, Massari R, Soluri A, Trezza V. Role of Nuclear Imaging to Understand the Neural Substrates of Brain Disorders in Laboratory Animals: Current Status and Future Prospects. Front Behav Neurosci 2020; 14:596509. [PMID: 33362486 PMCID: PMC7759612 DOI: 10.3389/fnbeh.2020.596509] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 11/23/2020] [Indexed: 12/18/2022] Open
Abstract
Molecular imaging, which allows the real-time visualization, characterization and measurement of biological processes, is becoming increasingly used in neuroscience research. Scintigraphy techniques such as single photon emission computed tomography (SPECT) and positron emission tomography (PET) provide qualitative and quantitative measurement of brain activity in both physiological and pathological states. Laboratory animals, and rodents in particular, are essential in neuroscience research, providing plenty of models of brain disorders. The development of innovative high-resolution small animal imaging systems together with their radiotracers pave the way to the study of brain functioning and neurotransmitter release during behavioral tasks in rodents. The assessment of local changes in the release of neurotransmitters associated with the performance of a given behavioral task is a turning point for the development of new potential drugs for psychiatric and neurological disorders. This review addresses the role of SPECT and PET small animal imaging systems for a better understanding of brain functioning in health and disease states. Brain imaging in rodent models faces a series of challenges since it acts within the boundaries of current imaging in terms of sensitivity and spatial resolution. Several topics are discussed, including technical considerations regarding the strengths and weaknesses of both technologies. Moreover, the application of some of the radioligands developed for small animal nuclear imaging studies is discussed. Then, we examine the changes in metabolic and neurotransmitter activity in various brain areas during task-induced neural activation with special regard to the imaging of opioid, dopaminergic and cannabinoid receptors. Finally, we discuss the current status providing future perspectives on the most innovative imaging techniques in small laboratory animals. The challenges and solutions discussed here might be useful to better understand brain functioning allowing the translation of preclinical results into clinical applications.
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Affiliation(s)
- Annunziata D'Elia
- Institute of Biochemistry and Cell Biology, National Research Council of Italy (CNR), Rome, Italy.,Section of Biomedical Sciences and Technologies, Department of Science, University "Roma Tre", Rome, Italy
| | - Sara Schiavi
- Section of Biomedical Sciences and Technologies, Department of Science, University "Roma Tre", Rome, Italy
| | - Andrea Soluri
- Institute of Biochemistry and Cell Biology, National Research Council of Italy (CNR), Rome, Italy
| | - Roberto Massari
- Institute of Biochemistry and Cell Biology, National Research Council of Italy (CNR), Rome, Italy
| | - Alessandro Soluri
- Institute of Biochemistry and Cell Biology, National Research Council of Italy (CNR), Rome, Italy
| | - Viviana Trezza
- Section of Biomedical Sciences and Technologies, Department of Science, University "Roma Tre", Rome, Italy
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3
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Tangherlini G, Börgel F, Schepmann D, Slocum S, Che T, Wagner S, Schwegmann K, Hermann S, Mykicki N, Loser K, Wünsch B. Synthesis and Pharmacological Evaluation of Fluorinated Quinoxaline-Based κ-Opioid Receptor (KOR) Agonists Designed for PET Studies. ChemMedChem 2020; 15:1834-1853. [PMID: 33448685 PMCID: PMC7589326 DOI: 10.1002/cmdc.202000502] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Indexed: 12/19/2022]
Abstract
κ-Opioid receptors (KORs) play a predominant role in pain alleviation, itching skin diseases, depression and neurodegenerative disorders such as multiple sclerosis. Therefore, imaging of KOR by a fluorinated PET tracer was envisaged. Two strategies were followed to introduce a F atom into the very potent class of cis,trans-configured perhydroquinoxalines. Whereas the synthesis of fluoroethyltriazole 2 has already been reported, fluoropyrrolidines 14 (1-[2-(3,4-dichlorophenyl)acetyl]-8-[(R)-3-fluoropyrrolidin-1-yl]-perhydroquinoxalines) were prepared by SN2 substitution of a cyclic sulfuric acid derivative with hydroxypyrrolidine and subsequent transformation of the OH moiety into a F substituent. Fluoropyrrolidines 14 showed similar low-nanomolar KOR affinity and selectivity to the corresponding pyrrolidines, but the corresponding alcohols were slightly less active. In the cAMP and β-arrestin assay, 14b (proton at the 4-position) exhibited similar KOR agonistic activity as U-50,488. The fluoro derivatives 14b and 14c (CO2CH3 at the 4-position) revealed KOR-mediated anti-inflammatory activity as CD11c and the IFN-γ production were reduced significantly in mouse and human dendritic cells. Compounds 14b and 14-c also displayed anti-inflammatory and immunomodulatory activity in mouse and human T cells. The PET tracer [18F]-2 was prepared by 1,3-dipolar cycloaddition. In vivo, [18F]-2 did not label KOR due to very fast elimination kinetics. Nucleophilic substitution of a mesylate precursor provided [18F]-14c. Unfortunately, defluorination of [18F]-14c occurred in vivo, which was analyzed in detail by in vitro studies.
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Affiliation(s)
- Giovanni Tangherlini
- Institut für Pharmazeutische und Medizinische ChemieUniversität MünsterCorrensstraße 4848149MünsterGermany
- Cells-in-Motion Cluster of Excellence (EXC 1003-CiM)Westfälische Wilhelms-Universität Münster48149MünsterGermany
| | - Frederik Börgel
- Institut für Pharmazeutische und Medizinische ChemieUniversität MünsterCorrensstraße 4848149MünsterGermany
| | - Dirk Schepmann
- Institut für Pharmazeutische und Medizinische ChemieUniversität MünsterCorrensstraße 4848149MünsterGermany
| | - Samuel Slocum
- Department of PharmacologyUniversity of North Carolina at Chapel Hill School of MedicineChapel HillNC 27599USA
| | - Tao Che
- Department of AnesthesiologyWashington University School of Medicine660 S. Euclid Ave.St. LouisMO 63110USA
| | - Stefan Wagner
- Department of Nuclear MedicineUniversity Hospital MünsterAlbert-Schweitzer-Campus 1, Building A148149MünsterGermany
| | - Katrin Schwegmann
- European Institute for Molecular Imaging (EIMI)University of MünsterWaldeyerstraße 1548149MünsterGermany
| | - Sven Hermann
- European Institute for Molecular Imaging (EIMI)University of MünsterWaldeyerstraße 1548149MünsterGermany
| | - Nadine Mykicki
- Department of DermatologyUniversity of Münstervon-Esmarch-Str. 5848149MünsterGermany
| | - Karin Loser
- Cells-in-Motion Cluster of Excellence (EXC 1003-CiM)Westfälische Wilhelms-Universität Münster48149MünsterGermany
- Department of DermatologyUniversity of Münstervon-Esmarch-Str. 5848149MünsterGermany
- CRC1009 Breaking Barriers and CRC-TR 128 Multiple SclerosisUniversity of Münstervon-Esmarch-Str. 5848149MünsterGermany
| | - Bernhard Wünsch
- Institut für Pharmazeutische und Medizinische ChemieUniversität MünsterCorrensstraße 4848149MünsterGermany
- Cells-in-Motion Cluster of Excellence (EXC 1003-CiM)Westfälische Wilhelms-Universität Münster48149MünsterGermany
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4
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Socała K, Doboszewska U, Wlaź P. Salvinorin A Does Not Affect Seizure Threshold in Mice. Molecules 2020; 25:molecules25051204. [PMID: 32155979 PMCID: PMC7179429 DOI: 10.3390/molecules25051204] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 03/04/2020] [Accepted: 03/05/2020] [Indexed: 11/16/2022] Open
Abstract
The κ-opioid receptor has recently gained attention as a new molecular target in the treatment of many psychiatric and neurological disorders including epilepsy. Salvinorin A is a potent plant-derived hallucinogen that acts as a highly selective κ-opioid receptor agonist. It has unique structure and pharmacological properties, but its influence on seizure susceptibility has not been studied so far. Therefore, the aim of the present study was to investigate the effect of salvinorin A on seizure thresholds in three acute seizure tests in mice. We also examined its effect on muscular strength and motor coordination. The obtained results showed that salvinorin A (0.1-10 mg/kg, i.p.) did not significantly affect the thresholds for the first myoclonic twitch, generalized clonic seizure, or forelimb tonus in the intravenous pentylenetetrazole seizure threshold test in mice. Likewise, it failed to affect the thresholds for tonic hindlimb extension and psychomotor seizures in the maximal electroshock- and 6 Hz-induced seizure threshold tests, respectively. Moreover, no changes in motor coordination (assessed in the chimney test) or muscular strength (assessed in the grip-strength test) were observed. This is a preliminary report only, and further studies are warranted to better characterize the effects of salvinorin A on seizure and epilepsy.
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5
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A Survey of Molecular Imaging of Opioid Receptors. Molecules 2019; 24:molecules24224190. [PMID: 31752279 PMCID: PMC6891617 DOI: 10.3390/molecules24224190] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 11/11/2019] [Accepted: 11/13/2019] [Indexed: 01/09/2023] Open
Abstract
The discovery of endogenous peptide ligands for morphine binding sites occurred in parallel with the identification of three subclasses of opioid receptor (OR), traditionally designated as μ, δ, and κ, along with the more recently defined opioid-receptor-like (ORL1) receptor. Early efforts in opioid receptor radiochemistry focused on the structure of the prototype agonist ligand, morphine, although N-[methyl-11C]morphine, -codeine and -heroin did not show significant binding in vivo. [11C]Diprenorphine ([11C]DPN), an orvinol type, non-selective OR antagonist ligand, was among the first successful PET tracers for molecular brain imaging, but has been largely supplanted in research studies by the μ-preferring agonist [11C]carfentanil ([11C]Caf). These two tracers have the property of being displaceable by endogenous opioid peptides in living brain, thus potentially serving in a competition-binding model. Indeed, many clinical PET studies with [11C]DPN or [11C]Caf affirm the release of endogenous opioids in response to painful stimuli. Numerous other PET studies implicate μ-OR signaling in aspects of human personality and vulnerability to drug dependence, but there have been very few clinical PET studies of μORs in neurological disorders. Tracers based on naltrindole, a non-peptide antagonist of the δ-preferring endogenous opioid enkephalin, have been used in PET studies of δORs, and [11C]GR103545 is validated for studies of κORs. Structures such as [11C]NOP-1A show selective binding at ORL-1 receptors in living brain. However, there is scant documentation of δ-, κ-, or ORL1 receptors in healthy human brain or in neurological and psychiatric disorders; here, clinical PET research must catch up with recent progress in radiopharmaceutical chemistry.
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Colom M, Vidal B, Zimmer L. Is There a Role for GPCR Agonist Radiotracers in PET Neuroimaging? Front Mol Neurosci 2019; 12:255. [PMID: 31680859 PMCID: PMC6813225 DOI: 10.3389/fnmol.2019.00255] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 10/02/2019] [Indexed: 12/30/2022] Open
Abstract
Positron emission tomography (PET) is a molecular imaging modality that enables in vivo exploration of metabolic processes and especially the pharmacology of neuroreceptors. G protein-coupled receptors (GPCRs) play an important role in numerous pathophysiologic disorders of the central nervous system. Thus, they are targets of choice in PET imaging to bring proof concept of change in density in pathological conditions or in pharmacological challenge. At present, most radiotracers are antagonist ligands. In vitro data suggest that properties differ between GPCR agonists and antagonists: antagonists bind to receptors with a single affinity, whereas agonists are characterized by two different affinities: high affinity for receptors that undergo functional coupling to G-proteins, and low affinity for those that are not coupled. In this context, agonist radiotracers may be useful tools to give functional images of GPCRs in the brain, with high sensitivity to neurotransmitter release. Here, we review all existing PET radiotracers used from animals to humans and their role for understanding the ligand-receptor paradigm of GPCR in comparison with corresponding antagonist radiotracers.
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Affiliation(s)
- Matthieu Colom
- Lyon Neuroscience Research Center, INSERM, CNRS, Université de Lyon, Lyon, France.,CERMEP, Hospices Civils de Lyon, Bron, France
| | - Benjamin Vidal
- Lyon Neuroscience Research Center, INSERM, CNRS, Université de Lyon, Lyon, France
| | - Luc Zimmer
- Lyon Neuroscience Research Center, INSERM, CNRS, Université de Lyon, Lyon, France.,CERMEP, Hospices Civils de Lyon, Bron, France.,Institut National des Sciences et Techniques Nucléaires, CEA Saclay, Gif-sur-Yvette, France
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7
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Martinez D, Slifstein M, Matuskey D, Nabulsi N, Zheng MQ, Lin SF, Ropchan J, Urban N, Grassetti A, Chang D, Salling M, Foltin R, Carson RE, Huang Y. Kappa-opioid receptors, dynorphin, and cocaine addiction: a positron emission tomography study. Neuropsychopharmacology 2019; 44:1720-1727. [PMID: 31026862 PMCID: PMC6785004 DOI: 10.1038/s41386-019-0398-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 03/28/2019] [Accepted: 04/16/2019] [Indexed: 01/08/2023]
Abstract
Animal studies indicate that the kappa-opioid receptor/dynorphin system plays an important role in cocaine binges and stress-induced relapse. Our goal was to investigate changes in kappa-opioid receptor (KOR) availability in the human brain using positron emission tomography (PET), before and after a cocaine binge. We also investigated the correlation between KOR and stress-induced cocaine self-administration. PET imaging was performed with the KOR selective agonist [11C]GR103545. Subjects with cocaine-use disorder (CUD) underwent PET scans and performed two types of cocaine self-administration sessions in the laboratory as follows: (1) choice sessions following a cold pressor test, to induce stress, and (2) binge dosing of cocaine. This allowed us investigate the following: (1) the association between KOR binding and a laboratory model of stress-induced relapse and (2) the change in KOR binding following a 3-day cocaine binge, which is thought to represent a change in endogenous dynorphin. A group of matched healthy controls was included to investigate between group differences in KOR availability. A significant association between [11C]GR103545 binding and cocaine self-administration was seen: greater KOR availability was associated with more choices for cocaine. In addition, the 3-day cocaine binge significantly reduced [11C]GR103545 binding by 18% in the striatum and 14% across brain regions. No difference in [11C]GR103545 binding was found between the CUD subjects and matched controls. In the context of previous studies, these findings add to the growing evidence that pharmacotherapies targeting the KOR have the potential to significantly impact treatment development for cocaine-use disorder.
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Affiliation(s)
- Diana Martinez
- Department of Psychiatry, Columbia University Irving Medical Center and the New York State Psychiatric Institute, New York, NY, USA.
| | - Mark Slifstein
- Department of Psychiatry, Columbia University Irving Medical Center and the New York State Psychiatric Institute, New York, NY, USA
| | - David Matuskey
- Yale PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Nabeel Nabulsi
- Yale PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Ming-Qiang Zheng
- Yale PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Shu-Fei Lin
- Yale PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Jim Ropchan
- Yale PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Nina Urban
- Department of Psychiatry, Columbia University Irving Medical Center and the New York State Psychiatric Institute, New York, NY, USA
| | - Alexander Grassetti
- Department of Psychiatry, Columbia University Irving Medical Center and the New York State Psychiatric Institute, New York, NY, USA
| | - Dinnisa Chang
- Department of Psychiatry, Columbia University Irving Medical Center and the New York State Psychiatric Institute, New York, NY, USA
| | - Michael Salling
- Department of Psychiatry, Columbia University Irving Medical Center and the New York State Psychiatric Institute, New York, NY, USA
| | - Richard Foltin
- Department of Psychiatry, Columbia University Irving Medical Center and the New York State Psychiatric Institute, New York, NY, USA
| | - Richard E Carson
- Yale PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Yiyun Huang
- Yale PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
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Sun J, Yang X, Zhang Y, Zhang W, Lu J, Hu Q, Liu R, Zhou C, Chen C. Salvinorin A attenuates early brain injury through PI3K/Akt pathway after subarachnoid hemorrhage in rat. Brain Res 2019; 1719:64-70. [PMID: 31125530 DOI: 10.1016/j.brainres.2019.05.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 05/17/2019] [Accepted: 05/20/2019] [Indexed: 02/01/2023]
Abstract
Early brain injury (EBI) refers to the direct injury to the brain during the first 72 h after subarachnoid hemorrhage (SAH), which is one of the major causes for the poor clinical outcome after SAH. In this study, we investigated the effect and the related mechanism of Salvinorin A (SA), a selective kappa opioid receptor agonist, on EBI after SAH. SA was administered by intraperitoneal injection at 24 h, 48 h and 72 h after SAH. The volume of lateral ventricle was measured by magnetic resonance imaging (MRI). The neuronal morphological changes and the apoptotic level in CA1 area of hippocampus were observed by Nissl and TUNEL staining respectively. Protein expression of p-PI3K, p-Akt, p-IKKα/β, p-NF-κB, FoxO1, Bim, Bax and Cleaved-caspase-3 was measured to explore the potential mechanism. We found that SA alleviated the neuronal morphological changes and apoptosis in CA1 area of hippocampus. The mechanism might be related to the increased protein expression of p-PI3K/p-Akt, which accompanied by decreased expression of p-IKKα/β, p-NF-κB, FoxO1, Bim, Bax and Cleaved-caspase-3 in the hippocampus. Thus, therapeutic interventions of SA targeting the PI3K/Akt pathway might be a novel approach to ameliorate EBI via reducing the apoptosis and inflammation after SAH.
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Affiliation(s)
- Juan Sun
- Department of Anatomy and Embryology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China; Department of Neurology, Affiliated Hospital of Qinghai University, China
| | - Xiaomei Yang
- Department of Anatomy and Embryology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Yan Zhang
- Department of Anatomy and Embryology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Weiguang Zhang
- Department of Anatomy and Embryology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Jianfei Lu
- Discipline of Neuroscience, Department of Anatomy and Physiology, Shanghai Jiao Tong University School of Medicine, China
| | - Qin Hu
- Discipline of Neuroscience, Department of Anatomy and Physiology, Shanghai Jiao Tong University School of Medicine, China
| | - Renyu Liu
- Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Changman Zhou
- Department of Anatomy and Embryology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Chunhua Chen
- Department of Anatomy and Embryology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China.
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Placzek MS, Schroeder FA, Che T, Wey HY, Neelamegam R, Wang C, Roth BL, Hooker JM. Discrepancies in Kappa Opioid Agonist Binding Revealed through PET Imaging. ACS Chem Neurosci 2019; 10:384-395. [PMID: 30212182 DOI: 10.1021/acschemneuro.8b00293] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Kappa opioid receptor (KOR) modulation has been pursued in many conceptual frameworks for the treatment of human pain, depression, and anxiety. As such, several imaging tools have been developed to characterize the density of KORs in the human brain and its occupancy by exogenous drug-like compounds. While exploring the pharmacology of KOR tool compounds using positron emission tomography (PET), we observed discrepancies in the apparent competition binding as measured by changes in binding potential (BPND, binding potential with respect to non-displaceable uptake). This prompted us to systematically look at the relationships between baseline BPND maps for three common KOR PET radioligands, the antagonists [11C]LY2795050 and [11C]LY2459989, and the agonist [11C]GR103545. We then measured changes in BPND using kappa antagonists (naloxone, naltrexone, LY2795050, JDTic, nor-BNI), and found BPND was affected similarly between [11C]GR103545 and [11C]LY2459989. Longitudinal PET studies with nor-BNI and JDTic were also examined, and we observed a persistent decrease in [11C]GR103545 BPND up to 25 days after drug administration for both nor-BNI and JDTic. Kappa agonists were also administered, and butorphan and GR89696 (racemic GR103545) impacted binding to comparable levels between the two radiotracers. Of greatest significance, kappa agonists salvinorin A and U-50488 caused dramatic reductions in [11C]GR103545 BPND but did not change [11C]LY2459989 binding. This discrepancy was further examined in dose-response studies with each radiotracer as well as in vitro binding experiments.
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Affiliation(s)
- Michael S. Placzek
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Frederick A. Schroeder
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Tao Che
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27516, United States
| | - Hsiao-Ying Wey
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Ramesh Neelamegam
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Changning Wang
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Bryan L. Roth
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27516, United States
- National Institute of Mental Health Psychoactive Drug Screening Program (NIMH PDSP), School of Medicine, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27516, United States
- Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27516, United States
| | - Jacob M. Hooker
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, United States
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10
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Burns JA, Kroll DS, Feldman DE, Kure Liu C, Manza P, Wiers CE, Volkow ND, Wang GJ. Molecular Imaging of Opioid and Dopamine Systems: Insights Into the Pharmacogenetics of Opioid Use Disorders. Front Psychiatry 2019; 10:626. [PMID: 31620026 PMCID: PMC6759955 DOI: 10.3389/fpsyt.2019.00626] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 08/05/2019] [Indexed: 12/21/2022] Open
Abstract
Opioid use in the United States has steadily risen since the 1990s, along with staggering increases in addiction and overdose fatalities. With this surge in prescription and illicit opioid abuse, it is paramount to understand the genetic risk factors and neuropsychological effects of opioid use disorder (OUD). Polymorphisms disrupting the opioid and dopamine systems have been associated with increased risk for developing substance use disorders. Molecular imaging studies have revealed how these polymorphisms impact the brain and contribute to cognitive and behavioral differences across individuals. Here, we review the current molecular imaging literature to assess how genetic variations in the opioid and dopamine systems affect function in the brain's reward, cognition, and stress pathways, potentially resulting in vulnerabilities to OUD. Continued research of the functional consequences of genetic variants and corresponding alterations in neural mechanisms will inform prevention and treatment of OUD.
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Affiliation(s)
- Jamie A Burns
- National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, United States
| | - Danielle S Kroll
- National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, United States
| | - Dana E Feldman
- National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, United States
| | | | - Peter Manza
- National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, United States
| | - Corinde E Wiers
- National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, United States
| | - Nora D Volkow
- National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, United States.,National Institute on Drug Abuse, Bethesda, MD, United States
| | - Gene-Jack Wang
- National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, United States
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11
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Miller JM, Zanderigo F, Purushothaman PD, DeLorenzo C, Rubin-Falcone H, Ogden RT, Keilp J, Oquendo MA, Nabulsi N, Huang YH, Parsey RV, Carson RE, Mann JJ. Kappa opioid receptor binding in major depression: A pilot study. Synapse 2018; 72:e22042. [PMID: 29935119 PMCID: PMC7599086 DOI: 10.1002/syn.22042] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 05/31/2018] [Accepted: 06/10/2018] [Indexed: 12/19/2022]
Abstract
Endogenous kappa opioids mediate pathological responses to stress in animal models. However, the relationship of the kappa opioid receptor (KOR) to life stress and to psychopathology in humans is not well described. This pilot study sought, for the first time, to quantify KOR in major depressive disorder (MDD) in vivo in humans using positron emission tomography (PET). KOR binding was quantified in vivo by PET imaging with the [11 C]GR103545 radiotracer in 13 healthy volunteers and 10 participants with current MDD. We examined the relationship between regional [11 C]GR103545 total volume of distribution (VT ) and diagnosis, childhood trauma, recent life stress, and, in a subsample, salivary cortisol levels during a modified Trier Social Stress Test (mTSST), amygdala, hippocampus, ventral striatum and raphe nuclei. Whole-brain voxel-wise analyses were also performed. [11 C]GR103545 VT did not differ significantly between MDD participants and healthy volunteers in the four a priori ROIs (p = 0.50). [11 C]GR103545 VT was unrelated to reported childhood adversity (p = 0.17) or recent life stress (p = 0.56). A trend-level inverse correlation was observed between [11 C]GR103545 VT and cortisol area-under-the curve with respect to ground during the mTSST (p = 0.081). No whole-brain voxel-wise contrasts were significant. Regional [11 C]GR103545 VT , a measure of in vivo KOR binding, does not differentiate MDD from healthy volunteers in this pilot sample. Future studies may examine KOR binding in subgroups of depressed individuals at increased risk for KOR abnormalities, including co-occurring mood and substance use disorders, as well as depression with psychotic features.
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Affiliation(s)
- Jeffrey M. Miller
- Division of Molecular Imaging and Neuropathology, New York State Psychiatric Institute, New York, NY
- Department of Psychiatry, Columbia University, New York, NY
| | - Francesca Zanderigo
- Division of Molecular Imaging and Neuropathology, New York State Psychiatric Institute, New York, NY
- Department of Psychiatry, Columbia University, New York, NY
| | | | - Christine DeLorenzo
- Department of Psychiatry and Behavioral Science, Stony Brook University School of Medicine
| | - Harry Rubin-Falcone
- Division of Molecular Imaging and Neuropathology, New York State Psychiatric Institute, New York, NY
- Department of Psychiatry, Columbia University, New York, NY
| | - R. Todd Ogden
- Division of Molecular Imaging and Neuropathology, New York State Psychiatric Institute, New York, NY
- Department of Biostatistics, Mailman School of Public Health, Columbia University, New York, NY
| | - John Keilp
- Division of Molecular Imaging and Neuropathology, New York State Psychiatric Institute, New York, NY
- Department of Psychiatry, Columbia University, New York, NY
| | - Maria A. Oquendo
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania
| | - Nabeel Nabulsi
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine
| | - Yiyun H. Huang
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine
| | - Ramin V. Parsey
- Department of Psychiatry and Behavioral Science, Stony Brook University School of Medicine
| | - Richard E. Carson
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine
| | - J. John Mann
- Division of Molecular Imaging and Neuropathology, New York State Psychiatric Institute, New York, NY
- Department of Psychiatry, Columbia University, New York, NY
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Abstract
PET has deep roots in neuroscience stemming from its first application in brain tumor and brain metabolism imaging. PET emerged over the past few decades and continues to play a prominent role in the study of neurochemistry in the living human brain. Over time, neurochemical imaging with PET has been expanded to address a host of research questions related to, among many others, protein density, drug occupancy, and endogenous neurochemical release. Each of these imaging modes has distinct design and analysis considerations that are critical for enabling quantitative measurements. The number of considerations required for a neurochemical PET study can make it unapproachable. This article aims to orient those interested in neurochemical PET imaging to three of the common imaging modes and to provide some perspective on needs that exist for expansion of neurochemical PET imaging.
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Affiliation(s)
- Michael S Placzek
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA; Department of Psychiatry, McLean Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA
| | - Wenjun Zhao
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA
| | - Hsiao-Ying Wey
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA
| | | | - Jacob M Hooker
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA.
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