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Chauveau F, Winkeler A, Chalon S, Boutin H, Becker G. PET imaging of neuroinflammation: any credible alternatives to TSPO yet? Mol Psychiatry 2024:10.1038/s41380-024-02656-9. [PMID: 38997465 DOI: 10.1038/s41380-024-02656-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 06/26/2024] [Accepted: 07/01/2024] [Indexed: 07/14/2024]
Abstract
Over the last decades, the role of neuroinflammation in neuropsychiatric conditions has attracted an exponentially growing interest. A key driver for this trend was the ability to image brain inflammation in vivo using PET radioligands targeting the Translocator Protein 18 kDa (TSPO), which is known to be expressed in activated microglia and astrocytes upon inflammatory events as well as constitutively in endothelial cells. TSPO is a mitochondrial protein that is expressed mostly by microglial cells upon activation but is also expressed by astrocytes in some conditions and constitutively by endothelial cells. Therefore, our current understanding of neuroinflammation dynamics is hampered by the lack of alternative targets available for PET imaging. We performed a systematic search and review on radiotracers developed for neuroinflammation PET imaging apart from TSPO. The following targets of interest were identified through literature screening (including previous narrative reviews): P2Y12R, P2X7R, CSF1R, COX (microglial targets), MAO-B, I2BS (astrocytic targets), CB2R & S1PRs (not specific of a single cell type). We determined the level of development and provided a scoping review for each target. Strikingly, astrocytic biomarker MAO-B has progressed in clinical investigations the furthest, while few radiotracers (notably targeting S1P1Rs, CSF1R) are being implemented in clinical investigations. Other targets such as CB2R and P2X7R have proven disappointing in clinical studies (e.g. poor signal, lack of changes in disease conditions, etc.). While astrocytic targets are promising, development of new biomarkers and tracers specific for microglial activation has proven challenging.
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Affiliation(s)
- Fabien Chauveau
- Université Claude Bernard Lyon 1, Centre de Recherche en Neurosciences de Lyon, Inserm U1028, CNRS UMR5292, BIORAN, Groupement Hospitalier Est - CERMEP, 59 boulevard Pinel, 69677, Bron, Cedex, France
| | - Alexandra Winkeler
- Université Paris-Saclay, Inserm, CNRS, CEA, BioMaps, Service Hospitalier Frédéric Joliot, 4 place du général Leclerc, 91401, Orsay, France
| | - Sylvie Chalon
- UMR 1253 iBrain, Université de Tours - INSERM, Bâtiment Planiol, UFR de Médecine, 10 Boulevard Tonnellé, 37032, Tours, Cedex 01, France
| | - Hervé Boutin
- UMR 1253 iBrain, Université de Tours - INSERM, Bâtiment Planiol, UFR de Médecine, 10 Boulevard Tonnellé, 37032, Tours, Cedex 01, France.
| | - Guillaume Becker
- Université Claude Bernard Lyon 1, Centre de Recherche en Neurosciences de Lyon, Inserm U1028, CNRS UMR5292, BIORAN, Groupement Hospitalier Est - CERMEP, 59 boulevard Pinel, 69677, Bron, Cedex, France
- Agence Nationale de Sécurité Sanitaire de l'Alimentation, de l'Environnement et du Travail, 14 rue Pierre et Marie Curie, 94701, Maisons-Alfort, Cedex, France
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Abstract
The cannabis plant has been used for centuries to manage the symptoms of various ailments including pain. Hundreds of chemical compounds have been identified and isolated from the plant and elicit a variety of physiological responses by binding to specific receptors and interacting with numerous other proteins. In addition, the body makes its own cannabinoid-like compounds that are integrally involved in modulating normal and pathophysiological processes. As the legal cannabis landscape continues to evolve within the United States and throughout the world, it is important to understand the rich science behind the effects of the plant and the implications for providers and patients. This narrative review aims to provide an overview of the basic science of the cannabinoids by describing the discovery and function of the endocannabinoid system, pharmacology of cannabinoids, and areas for future research and therapeutic development as they relate to perioperative and chronic pain medicine.
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Affiliation(s)
- Alexandra Sideris
- Department of Anesthesiology, Critical Care and Pain Medicine, Hospital for Special Surgery, New York, New York
- Department of Anesthesiology, Weill Cornell Medicine, New York, New York
- HSS Research Institute, New York, New York
| | | | - Martin Kaczocha
- Department of Anesthesiology, Renaissance School of Medicine, Stony Brook University, Stony Brook, New York
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Abou-El-Hassan H, Bernstock JD, Chalif JI, Yahya T, Rezende RM, Weiner HL, Izzy S. Elucidating the neuroimmunology of traumatic brain injury: methodological approaches to unravel intercellular communication and function. Front Cell Neurosci 2023; 17:1322325. [PMID: 38162004 PMCID: PMC10756680 DOI: 10.3389/fncel.2023.1322325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 11/15/2023] [Indexed: 01/03/2024] Open
Abstract
The neuroimmunology of traumatic brain injury (TBI) has recently gained recognition as a crucial element in the secondary pathophysiological consequences that occur following neurotrauma. Both immune cells residing within the central nervous system (CNS) and those migrating from the periphery play significant roles in the development of secondary brain injury. However, the precise mechanisms governing communication between innate and adaptive immune cells remain incompletely understood, partly due to a limited utilization of relevant experimental models and techniques. Therefore, in this discussion, we outline current methodologies that can aid in the exploration of TBI neuroimmunology, with a particular emphasis on the interactions between resident neuroglial cells and recruited lymphocytes. These techniques encompass adoptive cell transfer, intra-CNS injection(s), selective cellular depletion, genetic manipulation, molecular neuroimaging, as well as in vitro co-culture systems and the utilization of organoid models. By incorporating key elements of both innate and adaptive immunity, these methods facilitate the examination of clinically relevant interactions. In addition to these preclinical approaches, we also detail an emerging avenue of research that seeks to leverage human biofluids. This approach enables the investigation of how resident and infiltrating immune cells modulate neuroglial responses after TBI. Considering the growing significance of neuroinflammation in TBI, the introduction and application of advanced methodologies will be pivotal in advancing translational research in this field.
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Affiliation(s)
- Hadi Abou-El-Hassan
- Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Joshua D. Bernstock
- Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Joshua I. Chalif
- Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Taha Yahya
- Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Rafael M. Rezende
- Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Howard L. Weiner
- Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Saef Izzy
- Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
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Haider A, Wang L, Gobbi L, Li Y, Chaudhary A, Zhou X, Chen J, Zhao C, Rong J, Xiao Z, Hou L, Elghazawy NH, Sippl W, Davenport AT, Daunais JB, Ahmed H, Crowe R, Honer M, Rominger A, Grether U, Liang SH, Ametamey SM. Evaluation of [ 18F]RoSMA-18-d 6 as a CB2 PET Radioligand in Nonhuman Primates. ACS Chem Neurosci 2023; 14:3752-3760. [PMID: 37788055 DOI: 10.1021/acschemneuro.3c00222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023] Open
Abstract
The cannabinoid type 2 receptor (CB2) has been implicated in a variety of central and peripheral inflammatory diseases, prompting significant interest in the development of CB2-targeted diagnostic and therapeutic agents. A validated positron emission tomography (PET) radioligand for imaging CB2 in the living human brain as well as in peripheral tissues is currently lacking. As part of our research program, we have recently identified the trisubstituted pyridine, [18F]RoSMA-18-d6, which proved to be highly suitable for in vitro and in vivo mapping of CB2 in rodents. The aim of this study was to assess the performance characteristics of [18F]RoSMA-18-d6 in nonhuman primates (NHPs) to pave the way for clinical translation. [18F]RoSMA-18-d6 was synthesized from the respective tosylate precursor according to previously reported procedures. In vitro autoradiograms with NHP spleen tissue sections revealed a high binding of [18F]RoSMA-18-d6 to the CB2-rich NHP spleen, which was significantly blocked by coincubation with the commercially available CB2 ligand, GW405833 (10 μM). In contrast, no specific binding was observed by in vitro autoradiography with NHP brain sections, which was in agreement with the notion of a CB2-deficient healthy mammalian brain. In vitro findings were corroborated by PET imaging experiments in NHPs, where [18F]RoSMA-18-d6 uptake in the spleen was dose-dependently attenuated with 1 and 5 mg/kg GW405833, while no specific brain signal was observed. Remarkably, we observed tracer uptake and retention in the NHP spinal cord, which was reduced by GW405833 blockade, pointing toward a potential utility of [18F]RoSMA-18-d6 in probing CB2-expressing cells in the bone marrow. If these observations are substantiated in NHP models of enhanced leukocyte proliferation in the bone marrow, [18F]RoSMA-18-d6 may serve as a valuable marker for hematopoietic activity in various pathologies. In conclusion, [18F]RoSMA-18-d6 proved to be a suitable PET radioligand for imaging CB2 in NHPs, supporting its translation to humans.
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Affiliation(s)
- Ahmed Haider
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, Massachusetts 02114, United States
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Lu Wang
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Luca Gobbi
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, 4070 Basel, Switzerland
| | - Yinlong Li
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Ahmad Chaudhary
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Xin Zhou
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Jiahui Chen
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Chunyu Zhao
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Jian Rong
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Zhiwei Xiao
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Lu Hou
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Nehal H Elghazawy
- Institute of Pharmacy, Department of Medicinal Chemistry, Martin-Luther-University Halle-Wittenberg, W.-Langenbeck-Str. 4, 06120 Halle, Germany
| | - Wolfgang Sippl
- Institute of Pharmacy, Department of Medicinal Chemistry, Martin-Luther-University Halle-Wittenberg, W.-Langenbeck-Str. 4, 06120 Halle, Germany
| | - April T Davenport
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston Salem, North Carolina 27157, United States
| | - James B Daunais
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston Salem, North Carolina 27157, United States
| | - Hazem Ahmed
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Institute of Pharmaceutical Sciences ETH, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland
| | - Ron Crowe
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Michael Honer
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, 4070 Basel, Switzerland
| | - Axel Rominger
- Department of Nuclear Medicine, Bern University Hospital, 3010 Bern, Switzerland
| | - Uwe Grether
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, 4070 Basel, Switzerland
| | - Steven H Liang
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Simon M Ametamey
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Institute of Pharmaceutical Sciences ETH, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland
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Maccarrone M, Di Marzo V, Gertsch J, Grether U, Howlett AC, Hua T, Makriyannis A, Piomelli D, Ueda N, van der Stelt M. Goods and Bads of the Endocannabinoid System as a Therapeutic Target: Lessons Learned after 30 Years. Pharmacol Rev 2023; 75:885-958. [PMID: 37164640 PMCID: PMC10441647 DOI: 10.1124/pharmrev.122.000600] [Citation(s) in RCA: 23] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 04/06/2023] [Accepted: 04/10/2023] [Indexed: 05/12/2023] Open
Abstract
The cannabis derivative marijuana is the most widely used recreational drug in the Western world and is consumed by an estimated 83 million individuals (∼3% of the world population). In recent years, there has been a marked transformation in society regarding the risk perception of cannabis, driven by its legalization and medical use in many states in the United States and worldwide. Compelling research evidence and the Food and Drug Administration cannabis-derived cannabidiol approval for severe childhood epilepsy have confirmed the large therapeutic potential of cannabidiol itself, Δ9-tetrahydrocannabinol and other plant-derived cannabinoids (phytocannabinoids). Of note, our body has a complex endocannabinoid system (ECS)-made of receptors, metabolic enzymes, and transporters-that is also regulated by phytocannabinoids. The first endocannabinoid to be discovered 30 years ago was anandamide (N-arachidonoyl-ethanolamine); since then, distinct elements of the ECS have been the target of drug design programs aimed at curing (or at least slowing down) a number of human diseases, both in the central nervous system and at the periphery. Here a critical review of our knowledge of the goods and bads of the ECS as a therapeutic target is presented to define the benefits of ECS-active phytocannabinoids and ECS-oriented synthetic drugs for human health. SIGNIFICANCE STATEMENT: The endocannabinoid system plays important roles virtually everywhere in our body and is either involved in mediating key processes of central and peripheral diseases or represents a therapeutic target for treatment. Therefore, understanding the structure, function, and pharmacology of the components of this complex system, and in particular of key receptors (like cannabinoid receptors 1 and 2) and metabolic enzymes (like fatty acid amide hydrolase and monoacylglycerol lipase), will advance our understanding of endocannabinoid signaling and activity at molecular, cellular, and system levels, providing new opportunities to treat patients.
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Affiliation(s)
- Mauro Maccarrone
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, Italy (M.M.); European Center for Brain Research, Santa Lucia Foundation, Rome, Italy (M.M.); Canada Excellence Research Chair on the Microbiome-Endocannabinoidome Axis in Metabolic Health, University of Laval, Quebec, Canada (V.D.); Institute of Biochemistry and Molecular Medicine, NCCR TransCure, University of Bern, Bern, Switzerland (J.G.); Roche Pharma Research & Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland (U.G.); Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, North Carolina (A.C.H.); iHuman Institute, ShanghaiTech University, Shanghai, China (T.H.); Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts (A.M.); Departments of Pharmaceutical Sciences and Biological Chemistry, University of California, Irvine, California (D.P.); Department of Biochemistry, Kagawa University School of Medicine, Miki, Kagawa, Japan (N.U.); Department of Molecular Physiology, Leiden Institute of Chemistry, Leiden University, Leiden, Netherlands (M.S.)
| | - Vincenzo Di Marzo
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, Italy (M.M.); European Center for Brain Research, Santa Lucia Foundation, Rome, Italy (M.M.); Canada Excellence Research Chair on the Microbiome-Endocannabinoidome Axis in Metabolic Health, University of Laval, Quebec, Canada (V.D.); Institute of Biochemistry and Molecular Medicine, NCCR TransCure, University of Bern, Bern, Switzerland (J.G.); Roche Pharma Research & Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland (U.G.); Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, North Carolina (A.C.H.); iHuman Institute, ShanghaiTech University, Shanghai, China (T.H.); Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts (A.M.); Departments of Pharmaceutical Sciences and Biological Chemistry, University of California, Irvine, California (D.P.); Department of Biochemistry, Kagawa University School of Medicine, Miki, Kagawa, Japan (N.U.); Department of Molecular Physiology, Leiden Institute of Chemistry, Leiden University, Leiden, Netherlands (M.S.)
| | - Jürg Gertsch
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, Italy (M.M.); European Center for Brain Research, Santa Lucia Foundation, Rome, Italy (M.M.); Canada Excellence Research Chair on the Microbiome-Endocannabinoidome Axis in Metabolic Health, University of Laval, Quebec, Canada (V.D.); Institute of Biochemistry and Molecular Medicine, NCCR TransCure, University of Bern, Bern, Switzerland (J.G.); Roche Pharma Research & Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland (U.G.); Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, North Carolina (A.C.H.); iHuman Institute, ShanghaiTech University, Shanghai, China (T.H.); Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts (A.M.); Departments of Pharmaceutical Sciences and Biological Chemistry, University of California, Irvine, California (D.P.); Department of Biochemistry, Kagawa University School of Medicine, Miki, Kagawa, Japan (N.U.); Department of Molecular Physiology, Leiden Institute of Chemistry, Leiden University, Leiden, Netherlands (M.S.)
| | - Uwe Grether
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, Italy (M.M.); European Center for Brain Research, Santa Lucia Foundation, Rome, Italy (M.M.); Canada Excellence Research Chair on the Microbiome-Endocannabinoidome Axis in Metabolic Health, University of Laval, Quebec, Canada (V.D.); Institute of Biochemistry and Molecular Medicine, NCCR TransCure, University of Bern, Bern, Switzerland (J.G.); Roche Pharma Research & Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland (U.G.); Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, North Carolina (A.C.H.); iHuman Institute, ShanghaiTech University, Shanghai, China (T.H.); Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts (A.M.); Departments of Pharmaceutical Sciences and Biological Chemistry, University of California, Irvine, California (D.P.); Department of Biochemistry, Kagawa University School of Medicine, Miki, Kagawa, Japan (N.U.); Department of Molecular Physiology, Leiden Institute of Chemistry, Leiden University, Leiden, Netherlands (M.S.)
| | - Allyn C Howlett
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, Italy (M.M.); European Center for Brain Research, Santa Lucia Foundation, Rome, Italy (M.M.); Canada Excellence Research Chair on the Microbiome-Endocannabinoidome Axis in Metabolic Health, University of Laval, Quebec, Canada (V.D.); Institute of Biochemistry and Molecular Medicine, NCCR TransCure, University of Bern, Bern, Switzerland (J.G.); Roche Pharma Research & Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland (U.G.); Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, North Carolina (A.C.H.); iHuman Institute, ShanghaiTech University, Shanghai, China (T.H.); Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts (A.M.); Departments of Pharmaceutical Sciences and Biological Chemistry, University of California, Irvine, California (D.P.); Department of Biochemistry, Kagawa University School of Medicine, Miki, Kagawa, Japan (N.U.); Department of Molecular Physiology, Leiden Institute of Chemistry, Leiden University, Leiden, Netherlands (M.S.)
| | - Tian Hua
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, Italy (M.M.); European Center for Brain Research, Santa Lucia Foundation, Rome, Italy (M.M.); Canada Excellence Research Chair on the Microbiome-Endocannabinoidome Axis in Metabolic Health, University of Laval, Quebec, Canada (V.D.); Institute of Biochemistry and Molecular Medicine, NCCR TransCure, University of Bern, Bern, Switzerland (J.G.); Roche Pharma Research & Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland (U.G.); Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, North Carolina (A.C.H.); iHuman Institute, ShanghaiTech University, Shanghai, China (T.H.); Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts (A.M.); Departments of Pharmaceutical Sciences and Biological Chemistry, University of California, Irvine, California (D.P.); Department of Biochemistry, Kagawa University School of Medicine, Miki, Kagawa, Japan (N.U.); Department of Molecular Physiology, Leiden Institute of Chemistry, Leiden University, Leiden, Netherlands (M.S.)
| | - Alexandros Makriyannis
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, Italy (M.M.); European Center for Brain Research, Santa Lucia Foundation, Rome, Italy (M.M.); Canada Excellence Research Chair on the Microbiome-Endocannabinoidome Axis in Metabolic Health, University of Laval, Quebec, Canada (V.D.); Institute of Biochemistry and Molecular Medicine, NCCR TransCure, University of Bern, Bern, Switzerland (J.G.); Roche Pharma Research & Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland (U.G.); Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, North Carolina (A.C.H.); iHuman Institute, ShanghaiTech University, Shanghai, China (T.H.); Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts (A.M.); Departments of Pharmaceutical Sciences and Biological Chemistry, University of California, Irvine, California (D.P.); Department of Biochemistry, Kagawa University School of Medicine, Miki, Kagawa, Japan (N.U.); Department of Molecular Physiology, Leiden Institute of Chemistry, Leiden University, Leiden, Netherlands (M.S.)
| | - Daniele Piomelli
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, Italy (M.M.); European Center for Brain Research, Santa Lucia Foundation, Rome, Italy (M.M.); Canada Excellence Research Chair on the Microbiome-Endocannabinoidome Axis in Metabolic Health, University of Laval, Quebec, Canada (V.D.); Institute of Biochemistry and Molecular Medicine, NCCR TransCure, University of Bern, Bern, Switzerland (J.G.); Roche Pharma Research & Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland (U.G.); Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, North Carolina (A.C.H.); iHuman Institute, ShanghaiTech University, Shanghai, China (T.H.); Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts (A.M.); Departments of Pharmaceutical Sciences and Biological Chemistry, University of California, Irvine, California (D.P.); Department of Biochemistry, Kagawa University School of Medicine, Miki, Kagawa, Japan (N.U.); Department of Molecular Physiology, Leiden Institute of Chemistry, Leiden University, Leiden, Netherlands (M.S.)
| | - Natsuo Ueda
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, Italy (M.M.); European Center for Brain Research, Santa Lucia Foundation, Rome, Italy (M.M.); Canada Excellence Research Chair on the Microbiome-Endocannabinoidome Axis in Metabolic Health, University of Laval, Quebec, Canada (V.D.); Institute of Biochemistry and Molecular Medicine, NCCR TransCure, University of Bern, Bern, Switzerland (J.G.); Roche Pharma Research & Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland (U.G.); Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, North Carolina (A.C.H.); iHuman Institute, ShanghaiTech University, Shanghai, China (T.H.); Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts (A.M.); Departments of Pharmaceutical Sciences and Biological Chemistry, University of California, Irvine, California (D.P.); Department of Biochemistry, Kagawa University School of Medicine, Miki, Kagawa, Japan (N.U.); Department of Molecular Physiology, Leiden Institute of Chemistry, Leiden University, Leiden, Netherlands (M.S.)
| | - Mario van der Stelt
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, Italy (M.M.); European Center for Brain Research, Santa Lucia Foundation, Rome, Italy (M.M.); Canada Excellence Research Chair on the Microbiome-Endocannabinoidome Axis in Metabolic Health, University of Laval, Quebec, Canada (V.D.); Institute of Biochemistry and Molecular Medicine, NCCR TransCure, University of Bern, Bern, Switzerland (J.G.); Roche Pharma Research & Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland (U.G.); Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, North Carolina (A.C.H.); iHuman Institute, ShanghaiTech University, Shanghai, China (T.H.); Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts (A.M.); Departments of Pharmaceutical Sciences and Biological Chemistry, University of California, Irvine, California (D.P.); Department of Biochemistry, Kagawa University School of Medicine, Miki, Kagawa, Japan (N.U.); Department of Molecular Physiology, Leiden Institute of Chemistry, Leiden University, Leiden, Netherlands (M.S.)
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6
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Singh P, Singh D, Srivastava P, Mishra G, Tiwari AK. Evaluation of advanced, pathophysiologic new targets for imaging of CNS. Drug Dev Res 2023; 84:484-513. [PMID: 36779375 DOI: 10.1002/ddr.22040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Revised: 12/12/2022] [Accepted: 12/31/2022] [Indexed: 02/14/2023]
Abstract
The inadequate information about the in vivo pathological, physiological, and neurological impairments, as well as the absence of in vivo tools for assessing brain penetrance and the efficiency of newly designed drugs, has hampered the development of new techniques for the treatment for variety of new central nervous system (CNS) diseases. The searching sites such as Science Direct and PubMed were used to find out the numerous distinct tracers across 16 CNS targets including tau, synaptic vesicle glycoprotein, the adenosine 2A receptor, the phosphodiesterase enzyme PDE10A, and the purinoceptor, among others. Among the most encouraging are [18 F]FIMX for mGluR imaging, [11 C]Martinostat for Histone deacetylase, [18 F]MNI-444 for adenosine 2A imaging, [11 C]ER176 for translocator protein, and [18 F]MK-6240 for tau imaging. We also reviewed the findings for each tracer's features and potential for application in CNS pathophysiology and therapeutic evaluation investigations, including target specificity, binding efficacy, and pharmacokinetic factors. This review aims to present a current evaluation of modern positron emission tomography tracers for CNS targets, with a focus on recent advances for targets that have newly emerged for imaging in humans.
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Affiliation(s)
- Priya Singh
- Department of Chemistry, Babasaheb Bhimrao Ambedkar University, Lucknow, Uttar Pradesh, India
| | - Deepika Singh
- Department of Chemistry, Babasaheb Bhimrao Ambedkar University, Lucknow, Uttar Pradesh, India
| | - Pooja Srivastava
- Division of Cyclotron and Radiopharmaceuticals Sciences, Institute of Nuclear Medicine and Allied Sciences, Delhi, India
| | - Gauri Mishra
- Department of Zoology, Swami Shraddhananad College, University of Delhi, Alipur, Delhi, India
| | - Anjani K Tiwari
- Department of Chemistry, Babasaheb Bhimrao Ambedkar University, Lucknow, Uttar Pradesh, India
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Chen Z, Haider A, Chen J, Xiao Z, Gobbi L, Honer M, Grether U, Arnold SE, Josephson L, Liang SH. The Repertoire of Small-Molecule PET Probes for Neuroinflammation Imaging: Challenges and Opportunities beyond TSPO. J Med Chem 2021; 64:17656-17689. [PMID: 34905377 PMCID: PMC9094091 DOI: 10.1021/acs.jmedchem.1c01571] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Neuroinflammation is an adaptive response of the central nervous system to diverse potentially injurious stimuli, which is closely associated with neurodegeneration and typically characterized by activation of microglia and astrocytes. As a noninvasive and translational molecular imaging tool, positron emission tomography (PET) could provide a better understanding of neuroinflammation and its role in neurodegenerative diseases. Ligands to translator protein (TSPO), a putative marker of neuroinflammation, have been the most commonly studied in this context, but they suffer from serious limitations. Herein we present a repertoire of different structural chemotypes and novel PET ligand design for classical and emerging neuroinflammatory targets beyond TSPO. We believe that this Perspective will support multidisciplinary collaborations in academic and industrial institutions working on neuroinflammation and facilitate the progress of neuroinflammation PET probe development for clinical use.
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Affiliation(s)
- Zhen Chen
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, United States
| | - Ahmed Haider
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, United States
| | - Jiahui Chen
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, United States
| | - Zhiwei Xiao
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, United States
| | - Luca Gobbi
- Pharma Research and Early Development, F. Hoffmann-La Roche Ltd, CH-4070 Basel, Switzerland
| | - Michael Honer
- Pharma Research and Early Development, F. Hoffmann-La Roche Ltd, CH-4070 Basel, Switzerland
| | - Uwe Grether
- Pharma Research and Early Development, F. Hoffmann-La Roche Ltd, CH-4070 Basel, Switzerland
| | - Steven E. Arnold
- Department of Neurology and the Massachusetts Alzheimer’s Disease Research Center, Massachusetts General Hospital, Harvard Medical School, 114 16th Street, Charlestown, Massachusetts 02129, USA
| | - Lee Josephson
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, United States
| | - Steven H. Liang
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, United States
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8
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Nutma E, Ceyzériat K, Amor S, Tsartsalis S, Millet P, Owen DR, Papadopoulos V, Tournier BB. Cellular sources of TSPO expression in healthy and diseased brain. Eur J Nucl Med Mol Imaging 2021; 49:146-163. [PMID: 33433698 PMCID: PMC8712293 DOI: 10.1007/s00259-020-05166-2] [Citation(s) in RCA: 81] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 12/13/2020] [Indexed: 12/11/2022]
Abstract
The 18 kDa translocator protein (TSPO) is a highly conserved protein located in the outer mitochondrial membrane. TSPO binding, as measured with positron emission tomography (PET), is considered an in vivo marker of neuroinflammation. Indeed, TSPO expression is altered in neurodegenerative, neuroinflammatory, and neuropsychiatric diseases. In PET studies, the TSPO signal is often viewed as a marker of microglial cell activity. However, there is little evidence in support of a microglia-specific TSPO expression. This review describes the cellular sources and functions of TSPO in animal models of disease and human studies, in health, and in central nervous system diseases. A discussion of methods of analysis and of quantification of TSPO is also presented. Overall, it appears that the alterations of TSPO binding, their cellular underpinnings, and the functional significance of such alterations depend on many factors, notably the pathology or the animal model under study, the disease stage, and the involved brain regions. Thus, further studies are needed to fully determine how changes in TSPO binding occur at the cellular level with the ultimate goal of revealing potential therapeutic pathways.
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Affiliation(s)
- Erik Nutma
- Department of Pathology, Amsterdam UMC, VUmc, Amsterdam, The Netherlands
| | - Kelly Ceyzériat
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Avenue de la Roseraie, 64, 1206, Geneva, Switzerland
- Division of Nuclear medicine and Molecular Imaging, University Hospitals of Geneva, Geneva, Switzerland
- Division of Radiation Oncology, Department of Oncology, University Hospitals of Geneva, Geneva, Switzerland
| | - Sandra Amor
- Department of Pathology, Amsterdam UMC, VUmc, Amsterdam, The Netherlands
- Centre for Neuroscience and Trauma, Blizard Institute, Barts and the London School of Medicine & Dentistry, Queen Mary University of London, London, UK
| | - Stergios Tsartsalis
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Avenue de la Roseraie, 64, 1206, Geneva, Switzerland
- Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, UK
| | - Philippe Millet
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Avenue de la Roseraie, 64, 1206, Geneva, Switzerland
- Department of Psychiatry, University of Geneva, Geneva, Switzerland
| | - David R Owen
- Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, UK
| | - Vassilios Papadopoulos
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Benjamin B Tournier
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Avenue de la Roseraie, 64, 1206, Geneva, Switzerland.
- Department of Psychiatry, University of Geneva, Geneva, Switzerland.
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9
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Beaino W, Janssen B, Vugts DJ, de Vries HE, Windhorst AD. Towards PET imaging of the dynamic phenotypes of microglia. Clin Exp Immunol 2021; 206:282-300. [PMID: 34331705 PMCID: PMC8561701 DOI: 10.1111/cei.13649] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 07/21/2021] [Accepted: 07/21/2021] [Indexed: 02/06/2023] Open
Abstract
There is increasing evidence showing the heterogeneity of microglia activation in neuroinflammatory and neurodegenerative diseases. It has been hypothesized that pro‐inflammatory microglia are detrimental and contribute to disease progression, while anti‐inflammatory microglia play a role in damage repair and remission. The development of therapeutics targeting the deleterious glial activity and modulating it into a regenerative phenotype relies heavily upon a clearer understanding of the microglia dynamics during disease progression and the ability to monitor therapeutic outcome in vivo. To that end, molecular imaging techniques are required to assess microglia dynamics and study their role in disease progression as well as to evaluate the outcome of therapeutic interventions. Positron emission tomography (PET) is such a molecular imaging technique, and provides unique capabilities for non‐invasive quantification of neuroinflammation and has the potential to discriminate between microglia phenotypes and define their role in the disease process. However, several obstacles limit the possibility for selective in vivo imaging of microglia phenotypes mainly related to the poor characterization of specific targets that distinguish the two ends of the microglia activation spectrum and lack of suitable tracers. PET tracers targeting translocator protein 18 kDa (TSPO) have been extensively explored, but despite the success in evaluating neuroinflammation they failed to discriminate between microglia activation statuses. In this review, we highlight the current knowledge on the microglia phenotypes in the major neuroinflammatory and neurodegenerative diseases. We also discuss the current and emerging PET imaging targets, the tracers and their potential in discriminating between the pro‐ and anti‐inflammatory microglia activation states.
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Affiliation(s)
- Wissam Beaino
- Department of Radiology and Nuclear Medicine, Tracer Center Amsterdam, Amsterdam UMC, Vrije Universiteit, Amsterdam, the Netherlands
| | - Bieneke Janssen
- Department of Radiology and Nuclear Medicine, Tracer Center Amsterdam, Amsterdam UMC, Vrije Universiteit, Amsterdam, the Netherlands
| | - Danielle J Vugts
- Department of Radiology and Nuclear Medicine, Tracer Center Amsterdam, Amsterdam UMC, Vrije Universiteit, Amsterdam, the Netherlands
| | - Helga E de Vries
- Department of Molecular Cell Biology and Immunology, MS Center Amsterdam, Amsterdam Neuroscience, Amsterdam UMC, Vrije Universiteit, Amsterdam, the Netherlands
| | - Albert D Windhorst
- Department of Radiology and Nuclear Medicine, Tracer Center Amsterdam, Amsterdam UMC, Vrije Universiteit, Amsterdam, the Netherlands
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10
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Teodoro R, Gündel D, Deuther-Conrad W, Ueberham L, Toussaint M, Bormans G, Brust P, Moldovan RP. Development of [ 18F]LU14 for PET Imaging of Cannabinoid Receptor Type 2 in the Brain. Int J Mol Sci 2021; 22:ijms22158051. [PMID: 34360817 PMCID: PMC8347709 DOI: 10.3390/ijms22158051] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 07/20/2021] [Accepted: 07/23/2021] [Indexed: 12/16/2022] Open
Abstract
Cannabinoid receptors type 2 (CB2R) represent an attractive therapeutic target for neurodegenerative diseases and cancer. Aiming at the development of a positron emission tomography (PET) radiotracer to monitor receptor density and/or occupancy during a CB2R-tailored therapy, we herein describe the radiosynthesis of cis-[18F]1-(4-fluorobutyl-N-((1s,4s)-4-methylcyclohexyl)-2-oxo-1,2-dihydro-1,8-naphthyridine-3-carboxamide ([18F]LU14) starting from the corresponding mesylate precursor. The first biological evaluation revealed that [18F]LU14 is a highly affine CB2R radioligand with >80% intact tracer in the brain at 30 min p.i. Its further evaluation by PET in a well-established rat model of CB2R overexpression demonstrated its ability to selectively image the CB2R in the brain and its potential as a tracer to further investigate disease-related changes in CB2R expression.
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Affiliation(s)
- Rodrigo Teodoro
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Research, Department of Neuroradiopharmaceuticals, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (D.G.); (W.D.-C.); (L.U.); (M.T.); (P.B.)
| | - Daniel Gündel
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Research, Department of Neuroradiopharmaceuticals, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (D.G.); (W.D.-C.); (L.U.); (M.T.); (P.B.)
| | - Winnie Deuther-Conrad
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Research, Department of Neuroradiopharmaceuticals, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (D.G.); (W.D.-C.); (L.U.); (M.T.); (P.B.)
| | - Lea Ueberham
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Research, Department of Neuroradiopharmaceuticals, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (D.G.); (W.D.-C.); (L.U.); (M.T.); (P.B.)
| | - Magali Toussaint
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Research, Department of Neuroradiopharmaceuticals, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (D.G.); (W.D.-C.); (L.U.); (M.T.); (P.B.)
| | - Guy Bormans
- Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, BE-3000 Leuven, Belgium;
| | - Peter Brust
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Research, Department of Neuroradiopharmaceuticals, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (D.G.); (W.D.-C.); (L.U.); (M.T.); (P.B.)
- The Lübeck Institute of Experimental Dermatology, University Medical Center Schleswig-Holstein, 23562 Lübeck, Germany
| | - Rareş-Petru Moldovan
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Research, Department of Neuroradiopharmaceuticals, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (D.G.); (W.D.-C.); (L.U.); (M.T.); (P.B.)
- Correspondence: ; Tel.: +49-3412-3417-94634
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11
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Aly MW, Ludwig FA, Deuther-Conrad W, Brust P, Abadi AH, Moldovan RP, Osman NA. Development of fluorinated and methoxylated benzothiazole derivatives as highly potent and selective cannabinoid CB 2 receptor ligands. Bioorg Chem 2021; 114:105191. [PMID: 34375194 DOI: 10.1016/j.bioorg.2021.105191] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 07/15/2021] [Accepted: 07/16/2021] [Indexed: 11/25/2022]
Abstract
The upregulation of the CB2 receptors in neuroinflammation and cancer and their potential visualization with PET (positron emission tomography) could provide a valuable diagnostic and therapy-monitoring tool in such disorders. However, the availability of reliable CB2-selective imaging probes is still lacking in clinical practice. We have recently identified a benzothiazole-2-ylidine amide hit (6a) as a highly potent CB2 ligand. With the aim of enhancing its CB2 over CB1 selectivity and introducing structural sites suitable for radiolabeling, we herein describe the development of fluorinated and methoxylated benzothiazole derivatives endowed with extremely high CB2 binding affinity and an exclusive selectivity to the CB2 receptor. Compounds 14, 15, 18, 19, 21, 24 and 25 displayed subnanomolar CB2Ki values (ranging from 0.16 nM to 0.68 nM) and interestingly, all of the synthesized compounds completely lacked affinity at the CB1 receptor (Ki > 10,000 nM for all compounds), indicating their remarkably high CB2 over CB1 selectivity factors. The fluorinated analogs, 15 and 21, were evaluated for their in vitro metabolic stability in mouse and human liver microsomes (MLM and HLM). Both 15 and 21 displayed an exceptionally high stability (98% and 91% intact compounds, respectively) after 60 min incubation with MLM. Contrastingly, a 5- and 2.8-fold lower stability was demonstrated for compounds 15 and 21, respectively, upon incubation with HLM for 60 min. Taken together, our data present extremely potent and selective CB2 ligands as credible leads that can be further exploited for 18F- or 11C-radiolabeling and utilization as PET tracers.
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Affiliation(s)
- Mayar W Aly
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy and Biotechnology, German University in Cairo, Egypt
| | - Friedrich-Alexander Ludwig
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Department of Neuroradiopharmaceuticals, Research Site Leipzig, Leipzig 04318, Germany
| | - Winnie Deuther-Conrad
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Department of Neuroradiopharmaceuticals, Research Site Leipzig, Leipzig 04318, Germany
| | - Peter Brust
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Department of Neuroradiopharmaceuticals, Research Site Leipzig, Leipzig 04318, Germany
| | - Ashraf H Abadi
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy and Biotechnology, German University in Cairo, Egypt
| | - Rareş-Petru Moldovan
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Department of Neuroradiopharmaceuticals, Research Site Leipzig, Leipzig 04318, Germany.
| | - Noha A Osman
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy and Biotechnology, German University in Cairo, Egypt.
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12
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Thapa K, Grewal AS, Kanojia N, Rani L, Sharma N, Singh S. Alcoholic and Non-Alcoholic Liver Diseases: Promising Molecular Drug Targets and their Clinical Development. Curr Drug Discov Technol 2021; 18:333-353. [PMID: 31965945 DOI: 10.2174/1570163817666200121143959] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 11/25/2019] [Accepted: 12/04/2019] [Indexed: 11/22/2022]
Abstract
Alcoholic and non-alcoholic fatty liver diseases have become a serious concern worldwide. Both these liver diseases have an identical pathology, starting from simple steatosis to cirrhosis and, ultimately to hepatocellular carcinoma. Treatment options for alcoholic liver disease (ALD) are still the same as they were 50 years ago which include corticosteroids, pentoxifylline, antioxidants, nutritional support and abstinence; and for non-alcoholic fatty liver disease (NAFLD), weight loss, insulin sensitizers, lipid-lowering agents and anti-oxidants are the only treatment options. Despite broad research in understanding the disease pathophysiology, limited treatments are available for clinical use. Some therapeutic strategies based on targeting a specific molecule have been developed to lessen the consequences of disease and are under clinical investigation. Therefore, focus on multiple molecular targets will help develop an efficient therapeutic strategy. This review comprises a brief overview of the pathogenesis of ALD and NAFLD; recent molecular drug targets explored for ALD and NAFLD that may prove to be effective for multiple therapeutic regimens and also the clinical status of these promising drug targets for liver diseases.
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Affiliation(s)
- Komal Thapa
- Chitkara University School of Basic Sciences, Chitkara University, Himachal Pradesh, India
| | - Ajmer Singh Grewal
- Chitkara University School of Basic Sciences, Chitkara University, Himachal Pradesh, India
| | - Neha Kanojia
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
| | - Lata Rani
- Chitkara University School of Basic Sciences, Chitkara University, Himachal Pradesh, India
| | - Neelam Sharma
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
| | - Sukhbir Singh
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
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13
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Comprehensive review on design perspective of PET ligands based on β-amyloids, tau and neuroinflammation for diagnostic intervention of Alzheimer’s disease. Clin Transl Imaging 2021. [DOI: 10.1007/s40336-021-00410-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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14
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Preclinical Safety Evaluation and Human Dosimetry of [ 18F]MK-6240, a Novel PET Tracer for Imaging Neurofibrillary Tangles. Mol Imaging Biol 2021; 22:173-180. [PMID: 31111397 DOI: 10.1007/s11307-019-01367-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
PURPOSE [18F]MK-6240 is a selective, high-affinity positron emission tomography tracer for imaging neurofibrillary tangles, a key pathological signature that correlates with cognitive decline in Alzheimer disease. This report provides safety information from preclinical toxicology studies and first-in-human whole-body biodistribution and dosimetry studies of [18F]MK-6240 for its potential application in human brain imaging studies. PROCEDURES MK-6240 was administered intravenously (IV) in a 7-day rat toxicity study at × 50, × 100, and × 1000 dose margins relative to projected highest clinical dose of 0.333 μg/kg. The IV formulation of MK-6240 for clinical use and the formulation used in the 7-day rat toxicity study was tested for hemolysis potential in human and Wistar rat whole blood. Sequential whole-body positron emission tomography scans were performed in three healthy young subjects after IV bolus injection of 180 ± 0.3 MBq [18F]MK-6240 to characterize organ biodistribution and estimate whole-body radiation exposure (effective dose). RESULTS MK-6240 administered IV in a 7-day rat toxicity study did not show any test article-related changes. The no-observed-adverse-effect level in rats was ≥ 333 μg/kg/day which provides a margin 1000-fold over an anticipated maximum clinical dose of 0.333 μg/kg. Additionally, the MK-6240 formulation was not hemolytic in human or Wistar rat blood. [18F]MK-6240 activity was widely distributed to the brain and the rest of the body, with organ absorbed doses largest for the gall bladder (202 μGy/MBq). The average (±SD) effective dose was 29.4 ± 0.6 μSv/MBq, which is in the typical range for F-18 radiolabeled ligands. CONCLUSIONS Microdoses of [18F]MK-6240 are safe for clinical positron emission tomography imaging studies. Single IV administration of 185 MBq (5 mCi) [18F]MK-6240 is anticipated to result in a total human effective dose of 5.4 mSv and thus allows multiple positron emission tomography scans of the same subject per year.
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15
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Pascali G, Panetta D, De Simone M, Burchielli S, Lucchesi V, Sanguinetti E, Zanoni S, Iozzo P, Saccomanni G, Manera C, Salvadori PA. Preliminary Investigation of a Novel 18F Radiopharmaceutical for Imaging CB2 Receptors in a SOD Mouse Model. Aust J Chem 2021. [DOI: 10.1071/ch20247] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
We successfully radiolabelled a novel prospective cannabinoid type 2 receptor ligand with 18F and tested its biodistribution in animal models by positron emission tomography (PET)/computed tomography (CT) imaging. The radiolabelling process was conducted on an alkyl mesylate fragment of the main naphthyridine core, using highly efficient microfluidic technology. No preliminary protection was needed, and the product was purified by semi-prep HPLC and SPE formulation, allowing the desired diastereomeric mixture to be obtained in 29% radiochemical yield and>95% radiochemically pure. SOD1G93A mice were used as model of overexpression of CB2 receptors; PET imaging revealed a significant increase of the tracer distribution volume in the brain of symptomatic subjects compared with the asymptomatic ones.
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16
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17
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Cipollina G, Davari Serej A, Di Nolfi G, Gazzano A, Marsala A, Spatafora MG, Peviani M. Heterogeneity of Neuroinflammatory Responses in Amyotrophic Lateral Sclerosis: A Challenge or an Opportunity? Int J Mol Sci 2020; 21:E7923. [PMID: 33113845 PMCID: PMC7662281 DOI: 10.3390/ijms21217923] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/21/2020] [Accepted: 10/22/2020] [Indexed: 02/06/2023] Open
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a complex pathology: (i) the neurodegeneration is chronic and progressive; it starts focally in specific central nervous system (CNS) areas and spreads to different districts; (ii) multiple cell types further than motor neurons (i.e., glial/immune system cells) are actively involved in the disease; (iii) both neurosupportive and neurotoxic neuroinflammatory responses were identified. Microglia cells (a key player of neuroinflammation in the CNS) attracted great interest as potential target cell population that could be modulated to counteract disease progression, at least in preclinical ALS models. However, the heterogeneous/multifaceted microglia cell responses occurring in different CNS districts during the disease represent a hurdle for clinical translation of single-drug therapies. To address this issue, over the past ten years, several studies attempted to dissect the complexity of microglia responses in ALS. In this review, we shall summarize these results highlighting how the heterogeneous signature displayed by ALS microglia reflects not only the extent of neuronal demise in different regions of the CNS, but also variable engagement in the attempts to cope with the neuronal damage. We shall discuss novel avenues opened by the advent of single-cell and spatial transcriptomics technologies, underlining the potential for discovery of novel therapeutic targets, as well as more specific diagnostic/prognostic not-invasive markers of neuroinflammation.
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Affiliation(s)
| | | | | | | | | | | | - Marco Peviani
- Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, via Ferrata 9, 27100 Pavia, Italy; (G.C.); (A.D.S.); (G.D.N.); (A.G.); (A.M.); (M.G.S.)
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18
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Harms AS, Kordower JH, Sette A, Lindestam Arlehamn CS, Sulzer D, Mach RH. Inflammation in Experimental Models of α-Synucleinopathies. Mov Disord 2020; 36:37-49. [PMID: 33009855 DOI: 10.1002/mds.28264] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 05/29/2020] [Accepted: 06/17/2020] [Indexed: 12/11/2022] Open
Abstract
Neuroinflammation has long been associated with central nervous system pathology in α-synucleinopathy disorders including Parkinson's disease and multiple system atrophy. In the past decade, research-focused efforts in preclinical and experimental models have rallied around this idea, and considerable effort has been made to delineate critical neuroinflammatory processes. In this article, we discuss challenges in preclinical research, notably the use of animal models to recapitulate and dissect disease phenotypes as well as the need for more sensitive, reliable radiotracers to detect on-target efficacy of immunomodulatory treatments in both human Parkinson's disease as well as preclinical models. © 2020 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Ashley S Harms
- Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Jeffrey H Kordower
- Department of Neurological Sciences, Rush University Medical Center, Chicago, Illinois, USA
| | - Alessandro Sette
- Division of Vaccine Discovery, La Jolla Institute for Immunology, La Jolla, California, USA.,Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | | | - David Sulzer
- Department of Neurology, Columbia University Medical Center, New York, New York, USA.,Department of Psychiatry, Columbia University Medical Center, New York, New York, USA.,Department of Pharmacology, Columbia University Medical Center, New York, New York, USA
| | - Robert H Mach
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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19
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Haider A, Gobbi L, Kretz J, Ullmer C, Brink A, Honer M, Woltering TJ, Muri D, Iding H, Bürkler M, Binder M, Bartelmus C, Knuesel I, Pacher P, Herde AM, Spinelli F, Ahmed H, Atz K, Keller C, Weber M, Schibli R, Mu L, Grether U, Ametamey SM. Identification and Preclinical Development of a 2,5,6-Trisubstituted Fluorinated Pyridine Derivative as a Radioligand for the Positron Emission Tomography Imaging of Cannabinoid Type 2 Receptors. J Med Chem 2020; 63:10287-10306. [PMID: 32787079 DOI: 10.1021/acs.jmedchem.0c00778] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Despite the broad implications of the cannabinoid type 2 receptor (CB2) in neuroinflammatory processes, a suitable CB2-targeted probe is currently lacking in clinical routine. In this work, we synthesized 15 fluorinated pyridine derivatives and tested their binding affinities toward CB2 and CB1. With a sub-nanomolar affinity (Ki for CB2) of 0.8 nM and a remarkable selectivity factor of >12,000 over CB1, RoSMA-18-d6 exhibited outstanding in vitro performance characteristics and was radiofluorinated with an average radiochemical yield of 10.6 ± 3.8% (n = 16) and molar activities ranging from 52 to 65 GBq/μmol (radiochemical purity > 99%). [18F]RoSMA-18-d6 showed exceptional CB2 attributes as demonstrated by in vitro autoradiography, ex vivo biodistribution, and positron emission tomography (PET). Further, [18F]RoSMA-18-d6 was used to detect CB2 upregulation on postmortem human ALS spinal cord tissues. Overall, these results suggest that [18F]RoSMA-18-d6 is a promising CB2 PET radioligand for clinical translation.
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Affiliation(s)
- Ahmed Haider
- Institute of Pharmaceutical Sciences, ETH Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland
| | - Luca Gobbi
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, 4070 Basel, Switzerland
| | - Julian Kretz
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, 4070 Basel, Switzerland
| | - Christoph Ullmer
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, 4070 Basel, Switzerland
| | - Andreas Brink
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, 4070 Basel, Switzerland
| | - Michael Honer
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, 4070 Basel, Switzerland
| | - Thomas J Woltering
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, 4070 Basel, Switzerland
| | - Dieter Muri
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, 4070 Basel, Switzerland
| | - Hans Iding
- Pharma Technical Development, F. Hoffmann-La Roche Ltd., 4070 Basel, Switzerland
| | - Markus Bürkler
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, 4070 Basel, Switzerland
| | - Martin Binder
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, 4070 Basel, Switzerland
| | - Christian Bartelmus
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, 4070 Basel, Switzerland
| | - Irene Knuesel
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, 4070 Basel, Switzerland
| | - Pal Pacher
- Laboratory of Cardiovascular Physiology and Tissue Injury, National Institute of Health/NIAAA, 5625 Fishers Lane, Rockville, 20852 Maryland, United States
| | - Adrienne Müller Herde
- Institute of Pharmaceutical Sciences, ETH Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland
| | - Francesco Spinelli
- Institute of Pharmaceutical Sciences, ETH Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland
| | - Hazem Ahmed
- Institute of Pharmaceutical Sciences, ETH Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland
| | - Kenneth Atz
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, 4070 Basel, Switzerland
| | - Claudia Keller
- Institute of Pharmaceutical Sciences, ETH Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland
| | - Markus Weber
- Neuromuscular Diseases Unit/ALS Clinic, Kantonsspital St. Gallen, 9007 St. Gallen, Switzerland
| | - Roger Schibli
- Institute of Pharmaceutical Sciences, ETH Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland.,Department of Nuclear Medicine, University Hospital Zurich, 8091 Zurich, Switzerland
| | - Linjing Mu
- Institute of Pharmaceutical Sciences, ETH Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland.,Department of Nuclear Medicine, University Hospital Zurich, 8091 Zurich, Switzerland
| | - Uwe Grether
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, 4070 Basel, Switzerland
| | - Simon M Ametamey
- Institute of Pharmaceutical Sciences, ETH Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland
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20
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Basagni F, Rosini M, Decker M. Functionalized Cannabinoid Subtype 2 Receptor Ligands: Fluorescent, PET, Photochromic and Covalent Molecular Probes. ChemMedChem 2020; 15:1374-1389. [PMID: 32578963 PMCID: PMC7497013 DOI: 10.1002/cmdc.202000298] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Indexed: 01/01/2023]
Abstract
Cannabinoid subtype 2 receptors (CB2 Rs) are G protein-coupled receptors (GPCRs) belonging to the endocannabinoid system, a complex network of signalling pathways leading to the regulation of key physiological processes. Interestingly, CB2 Rs are strongly up-regulated in pathological conditions correlated with the onset of inflammatory events like cancer and neurodegenerative diseases. Therefore, CB2 Rs represent an important biological target for therapeutic as well as diagnostic purposes. No CB2 R-selective drugs are yet on the market, thus underlining a that deeper comprehension of CB2 Rs' complex activation pathways and their role in the regulation of diseases is needed. Herein, we report an overview of pharmacological and imaging tools such as fluorescent, positron emission tomography (PET), photochromic and covalent selective CB2 R ligands. These molecular probes can be used in vitro as well as in vivo to investigate and explore the unravelled role(s) of CB2 Rs, and they can help to design suitable CB2 R-targeted drugs.
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Affiliation(s)
- Filippo Basagni
- Pharmaceutical and Medicinal Chemistry Institute of Pharmacy and Food ChemistryJulius Maximilian University of WürzburgAm Hubland97074WürzburgGermany
- Department of Pharmacy and BiotechnologyUniversity of BolognaVia Belmeloro 640126BolognaItaly
| | - Michela Rosini
- Department of Pharmacy and BiotechnologyUniversity of BolognaVia Belmeloro 640126BolognaItaly
| | - Michael Decker
- Pharmaceutical and Medicinal Chemistry Institute of Pharmacy and Food ChemistryJulius Maximilian University of WürzburgAm Hubland97074WürzburgGermany
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21
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Cavaliere C, Tramontano L, Fiorenza D, Alfano V, Aiello M, Salvatore M. Gliosis and Neurodegenerative Diseases: The Role of PET and MR Imaging. Front Cell Neurosci 2020; 14:75. [PMID: 32327973 PMCID: PMC7161920 DOI: 10.3389/fncel.2020.00075] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 03/13/2020] [Indexed: 12/16/2022] Open
Abstract
Glial activation characterizes most neurodegenerative and psychiatric diseases, often anticipating clinical manifestations and macroscopical brain alterations. Although imaging techniques have improved diagnostic accuracy in many neurological conditions, often supporting diagnosis, prognosis prediction and treatment outcome, very few molecular imaging probes, specifically focused on microglial and astrocytic activation, have been translated to a clinical setting. In this context, hybrid positron emission tomography (PET)/magnetic resonance (MR) scanners represent the most advanced tool for molecular imaging, combining the functional specificity of PET radiotracers (e.g., targeting metabolism, hypoxia, and inflammation) to both high-resolution and multiparametric information derived by MR in a single imaging acquisition session. This simultaneity of findings achievable by PET/MR, if useful for reciprocal technical adjustments regarding temporal and spatial cross-modal alignment/synchronization, opens still debated issues about its clinical value in neurological patients, possibly incompliant and highly variable from a clinical point of view. While several preclinical and clinical studies have investigated the sensitivity of PET tracers to track microglial (mainly TSPO ligands) and astrocytic (mainly MAOB ligands) activation, less studies have focused on MR specificity to this topic (e.g., through the assessment of diffusion properties and T2 relaxometry), and only few exploiting the integration of simultaneous hybrid acquisition. This review aims at summarizing and critically review the current state about PET and MR imaging for glial targets, as well as the potential added value of hybrid scanners for characterizing microglial and astrocytic activation.
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22
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Kallinen A, Boyd R, Lane S, Bhalla R, Mardon K, Stimson DHR, Werry EL, Fulton R, Connor M, Kassiou M. Synthesis and in vitro evaluation of fluorine-18 benzimidazole sulfones as CB2 PET-radioligands. Org Biomol Chem 2019; 17:5086-5098. [PMID: 31070218 DOI: 10.1039/c9ob00656g] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Cannabinoid type 2 receptor (CB2) is up-regulated on activated microglial cells and can potentially be used as a biomarker for PET-imaging of neuroinflammation. In this study the synthesis and pharmacological evaluation of novel fluorinated pyridyl and ethyl sulfone analogues of 2-(tert-butyl)-5-((2-fluoropyridin-4-yl)sulfonyl)-1-(2-methylpentyl)-1H-benzo[d]imidazole (rac-1a) are described. In general, the ligands showed low nanomolar potency (CB2 EC50 < 10 nM) and excellent selectivity over the CB1 subtype (>10 000×). Selected ligands 1d, 1e, 1g and 3l showing high CB2 binding affinity (Ki < 10 nM) were radiolabelled with fluorine-18 from chloropyridyl and alkyl tosylate precursors with good to high isolated radioactive yields (25-44%, non-decay corrected, at the end of synthesis). CB2-specific binding of the radioligand candidates [18F]-1d and [18F]-3l was assessed on rat spleen cryosections using in vitro autoradiography. The results warrant further in vivo evaluation of the tracer candidates as prospective CB2 PET-imaging agents.
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Affiliation(s)
- Annukka Kallinen
- School of Chemistry, The University of Sydney, NSW 2006, Australia.
| | - Rochelle Boyd
- Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, NSW 2109, Australia
| | - Samuel Lane
- Faculty of Health Sciences, The University of Sydney, NSW 2050, Australia
| | - Rajiv Bhalla
- The Centre for Advanced Imaging, The University of Queensland, QLD 4072, Australia
| | - Karine Mardon
- The Centre for Advanced Imaging, The University of Queensland, QLD 4072, Australia
| | - Damion H R Stimson
- The Centre for Advanced Imaging, The University of Queensland, QLD 4072, Australia
| | - Eryn L Werry
- School of Chemistry, The University of Sydney, NSW 2006, Australia.
| | - Roger Fulton
- Faculty of Health Sciences, The University of Sydney, NSW 2050, Australia
| | - Mark Connor
- Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, NSW 2109, Australia
| | - Michael Kassiou
- School of Chemistry, The University of Sydney, NSW 2006, Australia.
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23
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Bauckneht M, Capitanio S, Raffa S, Roccatagliata L, Pardini M, Lapucci C, Marini C, Sambuceti G, Inglese M, Gallo P, Cecchin D, Nobili F, Morbelli S. Molecular imaging of multiple sclerosis: from the clinical demand to novel radiotracers. EJNMMI Radiopharm Chem 2019; 4:6. [PMID: 31659498 PMCID: PMC6453990 DOI: 10.1186/s41181-019-0058-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 03/21/2019] [Indexed: 12/13/2022] Open
Abstract
Background Brain PET imaging with different tracers is mainly clinically used in the field of neurodegenerative diseases and brain tumors. In recent years, the potential usefulness of PET has also gained attention in the field of MS. In fact, MS is a complex disease and several processes can be selected as a target for PET imaging. The use of PET with several different tracers has been mainly evaluated in the research setting to investigate disease pathophysiology (i.e. phenotypes, monitoring of progression) or to explore its use a surrogate end-point in clinical trials. Results We have reviewed PET imaging studies in MS in humans and animal models. Tracers have been grouped according to their pathophysiological targets (ie. tracers for myelin kinetic, neuroinflammation, and neurodegeneration). The emerging clinical indication for brain PET imaging in the differential diagnosis of suspected tumefactive demyelinated plaques as well as the clinical potential provided by PET images in view of the recent introduction of PET/MR technology are also addressed. Conclusion While several preclinical and fewer clinical studies have shown results, full-scale clinical development programs are needed to translate molecular imaging technologies into a clinical reality that could ideally fit into current precision medicine perspectives.
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Affiliation(s)
- Matteo Bauckneht
- Nuclear Medicine Unit, IRCCS Ospedale Policlinico San Martino, Largo R. Benzi 10, 16132, Genoa, Italy.
| | - Selene Capitanio
- Nuclear Medicine Unit, IRCCS Ospedale Policlinico San Martino, Largo R. Benzi 10, 16132, Genoa, Italy
| | - Stefano Raffa
- Department of Health Sciences (DISSAL), University of Genova, Genoa, Italy
| | - Luca Roccatagliata
- Department of Health Sciences (DISSAL), University of Genova, Genoa, Italy.,Neuroradiology, IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Matteo Pardini
- Clinical Neurology, Department of Neuroscience (DINOGMI), University of Genoa, Genoa, Italy.,Clinica Neurologica, IRCCS Ospedale Policlinico, San Martino, Genoa, Italy
| | - Caterina Lapucci
- Clinical Neurology, Department of Neuroscience (DINOGMI), University of Genoa, Genoa, Italy
| | - Cecilia Marini
- Nuclear Medicine Unit, IRCCS Ospedale Policlinico San Martino, Largo R. Benzi 10, 16132, Genoa, Italy.,CNR Institute of Molecular Bioimaging and Physiology, Milan, Italy
| | - Gianmario Sambuceti
- Nuclear Medicine Unit, IRCCS Ospedale Policlinico San Martino, Largo R. Benzi 10, 16132, Genoa, Italy.,Department of Health Sciences (DISSAL), University of Genova, Genoa, Italy
| | - Matilde Inglese
- Clinical Neurology, Department of Neuroscience (DINOGMI), University of Genoa, Genoa, Italy.,Clinica Neurologica, IRCCS Ospedale Policlinico, San Martino, Genoa, Italy
| | - Paolo Gallo
- Multiple Sclerosis Centre of the Veneto Region, Department of Neurosciences DNS, University of Padua, Padua, Italy
| | - Diego Cecchin
- Nuclear Medicine Unit, Department of Medicine-DIMED, Padova University Hospital, Padua, Italy.,Padua Neuroscience Center, University of Padua, Padua, Italy
| | - Flavio Nobili
- Clinical Neurology, Department of Neuroscience (DINOGMI), University of Genoa, Genoa, Italy.,Clinica Neurologica, IRCCS Ospedale Policlinico, San Martino, Genoa, Italy
| | - Silvia Morbelli
- Nuclear Medicine Unit, IRCCS Ospedale Policlinico San Martino, Largo R. Benzi 10, 16132, Genoa, Italy.,Department of Health Sciences (DISSAL), University of Genova, Genoa, Italy
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24
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Ni R, Mu L, Ametamey S. Positron emission tomography of type 2 cannabinoid receptors for detecting inflammation in the central nervous system. Acta Pharmacol Sin 2019; 40:351-357. [PMID: 29921889 PMCID: PMC6460366 DOI: 10.1038/s41401-018-0035-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2017] [Accepted: 05/01/2018] [Indexed: 02/06/2023] Open
Abstract
Cannabinoid receptor CB2 (CB2R) is upregulated on activated microglia and astrocytes in the brain under inflammatory conditions and plays important roles in many neurological diseases, such as Alzheimer's disease, amyotrophic lateral sclerosis, and ischemic stroke. The advent of positron emission tomography (PET) using CB2R radiotracers has enabled the visualization of CB2R distribution in vivo in animal models of central nervous system inflammation, however translation to humans has been less successful. Several novel CB2R radiotracers have been developed and evaluated to quantify microglial activation. In this review, we summarize the recent preclinical and clinical imaging results of CB2R PET tracers and discuss the prospects of CB2R imaging using PET.
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Affiliation(s)
- Ruiqing Ni
- Department of Chemistry and Applied Biosciences, Center for Radiopharmaceutical Sciences of ETH-PSI-USZ, Institute of Pharmaceutical Sciences, ETH Zurich, Zurich, 8093, Switzerland.
| | - Linjing Mu
- Department of Chemistry and Applied Biosciences, Center for Radiopharmaceutical Sciences of ETH-PSI-USZ, Institute of Pharmaceutical Sciences, ETH Zurich, Zurich, 8093, Switzerland
- Department of Nuclear Medicine, University Hospital Zurich, Zurich, 8091, Switzerland
| | - Simon Ametamey
- Department of Chemistry and Applied Biosciences, Center for Radiopharmaceutical Sciences of ETH-PSI-USZ, Institute of Pharmaceutical Sciences, ETH Zurich, Zurich, 8093, Switzerland
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25
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Attili B, Celen S, Ahamed M, Koole M, Haute CVD, Vanduffel W, Bormans G. Preclinical evaluation of [ 18 F]MA3: a CB 2 receptor agonist radiotracer for PET. Br J Pharmacol 2019; 176:1481-1491. [PMID: 30588600 DOI: 10.1111/bph.14564] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 10/31/2018] [Accepted: 11/16/2018] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND AND PURPOSE Non-invasive in vivo imaging of cannabinoid CB2 receptors using PET is pursued to study neuroinflammation. The purpose of this study is to evaluate the in vivo binding specificity of [18 F]MA3, a CB2 receptor agonist, in a rat model with local overexpression of human (h) CB2 receptors. METHODS [18 F]MA3 was produced with good radiochemical yield and radiochemical purity. The radiotracer was evaluated in rats with local overexpression of hCB2 receptors and in a healthy non-human primate using PET. KEY RESULTS Ex vivo autoradiography demonstrated CB2 -specific binding of [18 F]MA3 in rat hCB2 receptor vector injected striatum. In a PET study, increased tracer binding in the hCB2 receptor vector-injected striatum compared to the contralateral control vector-injected striatum was observed. Binding in hCB2 receptor vector-injected striatum was blocked with a structurally non-related CB2 receptor inverse agonist, and a displacement study confirmed the reversibility of tracer binding. This study identified the utility of mutated inactive vector model for evaluation of CB2 receptor agonist PET tracers. [18 F]MA3 PET scans in the non-human primate showed good uptake and fast washout from brain, but no CB2 receptor-specific binding was observed. CONCLUSION AND IMPLICATIONS Evaluation of [18 F]MA3 in a rat model with local overexpression of hCB2 receptors showed CB2 receptor-specific and reversible tracer binding. [18 F]MA3 showed good brain uptake and subsequent washout in a healthy non-human primate, but no specific binding was observed. Further clinical evaluation of [18 F]MA3 in patients with neuroinflammation is warranted. LINKED ARTICLES This article is part of a themed section on 8th European Workshop on Cannabinoid Research. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.10/issuetoc.
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Affiliation(s)
- Bala Attili
- Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium
| | - Sofie Celen
- Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium
| | - Muneer Ahamed
- Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium
| | - Michel Koole
- Department of Nuclear Medicine and Molecular Imaging, UZ Gasthuisberg, Leuven, Belgium
| | - Chris Van Den Haute
- Laboratory for Neurobiology and Gene Therapy, Department of Neurosciences, KU Leuven, Leuven, Belgium.,Leuven Viral Vector Core, Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Wim Vanduffel
- Laboratory for Neuro- and Psychophysiology, Department of Neurosciences, KU Leuven, Leuven, Belgium
| | - Guy Bormans
- Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium
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26
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Development of brain PET imaging agents: Strategies for imaging neuroinflammation in Alzheimer's disease. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2019; 165:371-399. [DOI: 10.1016/bs.pmbts.2019.04.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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27
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Chaney A, Williams SR, Boutin H. In vivo molecular imaging of neuroinflammation in Alzheimer's disease. J Neurochem 2018; 149:438-451. [PMID: 30339715 PMCID: PMC6563454 DOI: 10.1111/jnc.14615] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 09/24/2018] [Accepted: 09/27/2018] [Indexed: 12/11/2022]
Abstract
It has become increasingly evident that neuroinflammation plays a critical role in the pathophysiology of Alzheimer's disease (AD) and other neurodegenerative disorders. Increased glial cell activation is consistently reported in both rodent models of AD and in AD patients. Moreover, recent genome wide association studies have revealed multiple genes associated with inflammation and immunity are significantly associated with an increased risk of AD development (e.g. TREM2). Non‐invasive in vivo detection and tracking of neuroinflammation is necessary to enhance our understanding of the contribution of neuroinflammation to the initiation and progression of AD. Importantly, accurate methods of quantifying neuroinflammation may aid early diagnosis and serve as an output for therapeutic monitoring and disease management. This review details current in vivo imaging biomarkers of neuroinflammation being explored and summarizes both pre‐clinical and clinical results from molecular imaging studies investigating the role of neuroinflammation in AD, with a focus on positron emission tomography and magnetic resonance spectroscopy (MRS). ![]()
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Affiliation(s)
- Aisling Chaney
- School of Health Sciences, Division of Informatics, Faculty of Biology, Medicine and Health, Manchester Academic Health Sciences Centre University of Manchester, Manchester, UK.,Wolfson Molecular Imaging Centre, Faculty of Biology, Medicine and Health and Manchester Academic Health Sciences Centre, University of Manchester, Manchester, UK
| | - Steve R Williams
- School of Health Sciences, Division of Informatics, Faculty of Biology, Medicine and Health, Manchester Academic Health Sciences Centre University of Manchester, Manchester, UK
| | - Herve Boutin
- Wolfson Molecular Imaging Centre, Faculty of Biology, Medicine and Health and Manchester Academic Health Sciences Centre, University of Manchester, Manchester, UK.,School of Biological Sciences, Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, UK
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28
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Greenwald MK. Anti-stress neuropharmacological mechanisms and targets for addiction treatment: A translational framework. Neurobiol Stress 2018; 9:84-104. [PMID: 30238023 PMCID: PMC6138948 DOI: 10.1016/j.ynstr.2018.08.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 07/30/2018] [Accepted: 08/10/2018] [Indexed: 12/18/2022] Open
Abstract
Stress-related substance use is a major challenge for treating substance use disorders. This selective review focuses on emerging pharmacotherapies with potential for reducing stress-potentiated seeking and consumption of nicotine, alcohol, marijuana, cocaine, and opioids (i.e., key phenotypes for the most commonly abused substances). I evaluate neuropharmacological mechanisms in experimental models of drug-maintenance and relapse, which translate more readily to individuals presenting for treatment (who have initiated and progressed). An affective/motivational systems model (three dimensions: valence, arousal, control) is mapped onto a systems biology of addiction approach for addressing this problem. Based on quality of evidence to date, promising first-tier neurochemical receptor targets include: noradrenergic (α1 and β antagonist, α2 agonist), kappa-opioid antagonist, nociceptin antagonist, orexin-1 antagonist, and endocannabinoid modulation (e.g., cannabidiol, FAAH inhibition); second-tier candidates may include corticotropin releasing factor-1 antagonists, serotonergic agents (e.g., 5-HT reuptake inhibitors, 5-HT3 antagonists), glutamatergic agents (e.g., mGluR2/3 agonist/positive allosteric modulator, mGluR5 antagonist/negative allosteric modulator), GABA-promoters (e.g., pregabalin, tiagabine), vasopressin 1b antagonist, NK-1 antagonist, and PPAR-γ agonist (e.g., pioglitazone). To address affective/motivational mechanisms of stress-related substance use, it may be advisable to combine agents with actions at complementary targets for greater efficacy but systematic studies are lacking except for interactions with the noradrenergic system. I note clinically-relevant factors that could mediate/moderate the efficacy of anti-stress therapeutics and identify research gaps that should be pursued. Finally, progress in developing anti-stress medications will depend on use of reliable CNS biomarkers to validate exposure-response relationships.
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Affiliation(s)
- Mark K. Greenwald
- Department of Psychiatry and Behavioral Neurosciences, School of Medicine, Department of Pharmacy Practice, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, MI, 48201, USA
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29
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Högel H, Rissanen E, Vuorimaa A, Airas L. Positron emission tomography imaging in evaluation of MS pathology in vivo. Mult Scler 2018; 24:1399-1412. [DOI: 10.1177/1352458518791680] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Positron emission tomography (PET) gives an opportunity to quantitate the expression of specific molecular targets in vivo and longitudinally in brain and thus enhances our possibilities to understand and follow up multiple sclerosis (MS)-related pathology. For successful PET imaging, one needs a relevant target molecule within the brain, to which a blood–brain barrier–penetrating specific radioligand will bind. 18-kDa translocator protein (TSPO)-binding radioligands have been used to detect activated microglial cells at different stages of MS, and remyelination has been measured using amyloid PET. Several PET ligands for the detection of other inflammatory targets, besides TSPO, have been developed but not yet been used for imaging MS patients. Finally, synaptic density evaluation has been successfully tested in human subjects and gives opportunities for the evaluation of the development of cortical and deep gray matter pathology in MS. This review will discuss PET imaging modalities relevant for MS today.
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Affiliation(s)
- Heidi Högel
- Turku PET Centre, Turku University Hospital and University of Turku, Turku, Finland/Division of Clinical Neurosciences, Turku University Hospital and University of Turku, Turku, Finland
| | - Eero Rissanen
- Turku PET Centre, Turku University Hospital and University of Turku, Turku, Finland/Division of Clinical Neurosciences, Turku University Hospital and University of Turku, Turku, Finland
| | - Anna Vuorimaa
- Turku PET Centre, Turku University Hospital and University of Turku, Turku, Finland/Division of Clinical Neurosciences, Turku University Hospital and University of Turku, Turku, Finland
| | - Laura Airas
- Turku PET Centre, Turku University Hospital and University of Turku, Turku, Finland/Division of Clinical Neurosciences, Turku University Hospital and University of Turku, Turku, Finland
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30
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Abstract
Neuroinflammation, which involves microglial activation, is thought to play a key role in the development and progression of neurodegenerative diseases and other brain pathologies. Positron emission tomography is an ideal imaging technique for studying biochemical processes in vivo, and particularly for studying the living brain. Neuroinflammation has been traditionally studied using radiotracers targeting the translocator protein 18 kDa, but this comes with certain limitations. The current review describes alternative biological targets that have gained interest for the imaging of microglial activation over recent years, such as the cannabinoid receptor type 2, cyclooxygenase-2, the P2X₇ receptor and reactive oxygen species, and some promising radiotracers for these targets. Although many advances have been made in the field of neuroinflammation imaging, current radiotracers all target the pro-inflammatory (M1) phenotype of activated microglia, since the number of known biological targets specific for the anti-inflammatory (M2) phenotype that are also suited as a target for radiotracer development is still limited. Next to proceeding the currently available tracers for M1 microglia into the clinic, the development of a suitable radiotracer for M2 microglia would mean a great advance in the field, as this would allow for imaging of the dynamics of microglial activation in different diseases.
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Affiliation(s)
- Bieneke Janssen
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Danielle J Vugts
- Department of Radiology & Nuclear Medicine, VU University Medical Center, 1081 HV Amsterdam, The Netherlands.
| | - Albert D Windhorst
- Department of Radiology & Nuclear Medicine, VU University Medical Center, 1081 HV Amsterdam, The Netherlands.
| | - Robert H Mach
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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31
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Spinelli F, Mu L, Ametamey SM. Radioligands for positron emission tomography imaging of cannabinoid type 2 receptor. J Labelled Comp Radiopharm 2017; 61:299-308. [PMID: 29110331 DOI: 10.1002/jlcr.3579] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Revised: 10/10/2017] [Accepted: 10/24/2017] [Indexed: 01/11/2023]
Abstract
The cannabinoid type 2 (CB2) receptor is an immunomodulatory receptor mainly expressed in peripheral cells and organs of the immune system. The expression level of CB2 in the central nervous system under physiological conditions is negligible, however under neuroinflammatory conditions an upregulation of CB2 protein or mRNA mainly colocalized with activated microglial cells has been reported. Consequently, CB2 agonists have been confirmed to play a role in neuroprotective and anti-inflammatory processes. A suitable positron emission tomography radioligand for imaging CB2 would provide an invaluable research tool to explore the role of CB2 receptor expression in inflammatory disorders. In this review, we provide a summary of so far published CB2 radioligands as well as their in vitro and in vivo binding characteristics.
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Affiliation(s)
- Francesco Spinelli
- Department of Pharmacy-Pharmaceutical Sciences, University of Bari "A. Moro", Bari, Italy.,Department of Chemistry and Applied Biosciences, Center for Radiopharmaceutical Sciences of ETH-PSI-USZ, Institute of Pharmaceutical Sciences, ETH Zurich, Zurich, Switzerland
| | - Linjing Mu
- Department of Nuclear Medicine, Center for Radiopharmaceutical Sciences of ETH-PSI-USZ, University Hospital Zurich, Zurich, Switzerland
| | - Simon M Ametamey
- Department of Chemistry and Applied Biosciences, Center for Radiopharmaceutical Sciences of ETH-PSI-USZ, Institute of Pharmaceutical Sciences, ETH Zurich, Zurich, Switzerland
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Cooper A, Singh S, Hook S, Tyndall JDA, Vernall AJ. Chemical Tools for Studying Lipid-Binding Class A G Protein-Coupled Receptors. Pharmacol Rev 2017; 69:316-353. [PMID: 28655732 DOI: 10.1124/pr.116.013243] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 05/15/2017] [Indexed: 12/16/2022] Open
Abstract
Cannabinoid, free fatty acid, lysophosphatidic acid, sphingosine 1-phosphate, prostanoid, leukotriene, bile acid, and platelet-activating factor receptor families are class A G protein-coupled receptors with endogenous lipid ligands. Pharmacological tools are crucial for studying these receptors and addressing the many unanswered questions surrounding expression of these receptors in normal and diseased tissues. An inherent challenge for developing tools for these lipid receptors is balancing the often lipophilic requirements of the receptor-binding pharmacophore with favorable physicochemical properties to optimize highly specific binding. In this study, we review the radioligands, fluorescent ligands, covalent ligands, and antibodies that have been used to study these lipid-binding receptors. For each tool type, the characteristics and design rationale along with in vitro and in vivo applications are detailed.
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Affiliation(s)
- Anna Cooper
- School of Pharmacy, University of Otago, Dunedin, New Zealand
| | - Sameek Singh
- School of Pharmacy, University of Otago, Dunedin, New Zealand
| | - Sarah Hook
- School of Pharmacy, University of Otago, Dunedin, New Zealand
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Caillé F, Cacheux F, Peyronneau MA, Jego B, Jaumain E, Pottier G, Ullmer C, Grether U, Winkeler A, Dollé F, Damont A, Kuhnast B. From Structure-Activity Relationships on Thiazole Derivatives to the In Vivo Evaluation of a New Radiotracer for Cannabinoid Subtype 2 PET Imaging. Mol Pharm 2017; 14:4064-4078. [PMID: 28968497 DOI: 10.1021/acs.molpharmaceut.7b00746] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Upregulation of the cannabinoid type 2 receptors (CB2R) unveils inflammation processes of pathological disorders, such as cancer, pain, or neurodegenerative diseases. Among others, CB2R agonist A-836339 has been labeled with carbon-11 for PET imaging of the CB2R and displayed promising results in a mouse model of Alzheimer's disease. The aim of the present work was to develop fluorinated analogs of A-836339 for labeling with fluorine-18 to design a new PET tracer for CB2R imaging. Seven fluorinated analogs of A-836339 were synthesized in two to three steps and their binding affinities and selectivities for both the human and the mouse CB2R were measured as well as their early ADME profiles. Among them, compound 2f (KihCB2R = 0.1 nM, KihCB1R/KihCB2R = 300) displayed high affinity and selectivity for CB2R but also promising lipophilicity, kinetic solubility, and membrane permeation properties and was further selected for in vitro metabolism studies. Incubation of 2f with human or rat liver microsomes followed by LC/MS analysis revealed the presence of six different metabolites mainly resulting from oxidation reactions. A tosylated precursor of 2f was synthesized in two steps and radiolabeled with fluorine-18 to afford [18F]2f in 15 ± 5% radiochemical yield and a molar activity of 110 ± 30 GBq/μmol. Autoradiographies of rat spleen and biodistribution studies in healthy rats including pretreatments with either CB2R or CB1R-specific compounds suggested that [18F]2f is a specific tracer for the CB2R in vivo. We have therefore demonstrated here that [18F]2f is a promising novel tracer for imaging CB2R in vivo using PET. Further investigation in animal models of inflammation will follow.
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Affiliation(s)
- Fabien Caillé
- UMR 1023 IMIV, Service Hospitalier Frédéric Joliot, CEA, Inserm, Université Paris Sud, CNRS, Université Paris-Saclay , 91405 Orsay, France
| | - Fanny Cacheux
- UMR 1023 IMIV, Service Hospitalier Frédéric Joliot, CEA, Inserm, Université Paris Sud, CNRS, Université Paris-Saclay , 91405 Orsay, France
| | - Marie-Anne Peyronneau
- UMR 1023 IMIV, Service Hospitalier Frédéric Joliot, CEA, Inserm, Université Paris Sud, CNRS, Université Paris-Saclay , 91405 Orsay, France
| | - Benoît Jego
- UMR 1023 IMIV, Service Hospitalier Frédéric Joliot, CEA, Inserm, Université Paris Sud, CNRS, Université Paris-Saclay , 91405 Orsay, France
| | - Emilie Jaumain
- UMR 1023 IMIV, Service Hospitalier Frédéric Joliot, CEA, Inserm, Université Paris Sud, CNRS, Université Paris-Saclay , 91405 Orsay, France
| | - Géraldine Pottier
- UMR 1023 IMIV, Service Hospitalier Frédéric Joliot, CEA, Inserm, Université Paris Sud, CNRS, Université Paris-Saclay , 91405 Orsay, France
| | - Christoph Ullmer
- Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd. , 4070 Basel, Switzerland
| | - Uwe Grether
- Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd. , 4070 Basel, Switzerland
| | - Alexandra Winkeler
- UMR 1023 IMIV, Service Hospitalier Frédéric Joliot, CEA, Inserm, Université Paris Sud, CNRS, Université Paris-Saclay , 91405 Orsay, France
| | - Frédéric Dollé
- UMR 1023 IMIV, Service Hospitalier Frédéric Joliot, CEA, Inserm, Université Paris Sud, CNRS, Université Paris-Saclay , 91405 Orsay, France
| | - Annelaure Damont
- UMR 1023 IMIV, Service Hospitalier Frédéric Joliot, CEA, Inserm, Université Paris Sud, CNRS, Université Paris-Saclay , 91405 Orsay, France
| | - Bertrand Kuhnast
- UMR 1023 IMIV, Service Hospitalier Frédéric Joliot, CEA, Inserm, Université Paris Sud, CNRS, Université Paris-Saclay , 91405 Orsay, France
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Tronel C, Largeau B, Santiago Ribeiro MJ, Guilloteau D, Dupont AC, Arlicot N. Molecular Targets for PET Imaging of Activated Microglia: The Current Situation and Future Expectations. Int J Mol Sci 2017; 18:ijms18040802. [PMID: 28398245 PMCID: PMC5412386 DOI: 10.3390/ijms18040802] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 03/15/2017] [Accepted: 03/28/2017] [Indexed: 12/13/2022] Open
Abstract
Microglia, as cellular mediators of neuroinflammation, are implicated in the pathogenesis of a wide range of neurodegenerative diseases. Positron emission tomography (PET) imaging of microglia has matured over the last 20 years, through the development of radiopharmaceuticals targeting several molecular biomarkers of microglial activation and, among these, mainly the translocator protein-18 kDa (TSPO). Nevertheless, current limitations of TSPO as a PET microglial biomarker exist, such as low brain density, even in a neurodegenerative setting, expression by other cells than the microglia (astrocytes, peripheral macrophages in the case of blood brain barrier breakdown), genetic polymorphism, inducing a variation for most of TSPO PET radiopharmaceuticals’ binding affinity, or similar expression in activated microglia regardless of its polarization (pro- or anti-inflammatory state), and these limitations narrow its potential interest. We overview alternative molecular targets, for which dedicated radiopharmaceuticals have been proposed, including receptors (purinergic receptors P2X7, cannabinoid receptors, α7 and α4β2 nicotinic acetylcholine receptors, adenosine 2A receptor, folate receptor β) and enzymes (cyclooxygenase, nitric oxide synthase, matrix metalloproteinase, β-glucuronidase, and enzymes of the kynurenine pathway), with a particular focus on their respective contribution for the understanding of microglial involvement in neurodegenerative diseases. We discuss opportunities for these potential molecular targets for PET imaging regarding their selectivity for microglia expression and polarization, in relation to the mechanisms by which microglia actively participate in both toxic and neuroprotective actions in brain diseases, and then take into account current clinicians’ expectations.
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Affiliation(s)
- Claire Tronel
- INSERM U930, Université François Rabelais de Tours, 10 boulevard Tonnelé, 37032 Tours, France.
| | | | - Maria Joao Santiago Ribeiro
- INSERM U930, Université François Rabelais de Tours, 10 boulevard Tonnelé, 37032 Tours, France.
- CHRU de Tours, 37044 Tours, France.
| | - Denis Guilloteau
- INSERM U930, Université François Rabelais de Tours, 10 boulevard Tonnelé, 37032 Tours, France.
- CHRU de Tours, 37044 Tours, France.
| | - Anne-Claire Dupont
- INSERM U930, Université François Rabelais de Tours, 10 boulevard Tonnelé, 37032 Tours, France.
- CHRU de Tours, 37044 Tours, France.
| | - Nicolas Arlicot
- INSERM U930, Université François Rabelais de Tours, 10 boulevard Tonnelé, 37032 Tours, France.
- CHRU de Tours, 37044 Tours, France.
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Pottier G, Gómez-Vallejo V, Padro D, Boisgard R, Dollé F, Llop J, Winkeler A, Martín A. PET imaging of cannabinoid type 2 receptors with [ 11C]A-836339 did not evidence changes following neuroinflammation in rats. J Cereb Blood Flow Metab 2017; 37:1163-1178. [PMID: 28079433 PMCID: PMC5363492 DOI: 10.1177/0271678x16685105] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Cannabinoid type 2 receptors (CB2R) have emerged as promising targets for the diagnosis and therapy of brain pathologies. However, no suitable radiotracers for accurate CB2R mapping have been found to date, limiting the investigation of the CB2 receptor expression using positron emission tomography (PET) imaging. In this work, we report the evaluation of the in vivo expression of CB2R with [11C]A-836339 PET after cerebral ischemia and in two rat models of neuroinflammation, first by intrastriatal LPS and then by AMPA injection. PET images and in vitro autoradiography showed a lack of specific [11C]A-836339 uptake in these animal models demonstrating the limitation of this radiotracer to image CB2 receptor under neuroinflammatory conditions. Further, using immunohistochemistry, the CB2 receptor displayed a modest expression increase after cerebral ischemia, LPS and AMPA models. Finally, [18F]DPA-714-PET and immunohistochemistry demonstrated decreased neuroinflammation by a selective CB2R agonist, JWH133. Taken together, these findings suggest that [11C]A-836339 is not a suitable radiotracer to monitor in vivo CB2R expression by using PET imaging. Future studies will have to investigate alternative radiotracers that could provide an accurate binding to CB2 receptors following brain inflammation.
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Affiliation(s)
- Geraldine Pottier
- 1 Imagerie Moléculaire In Vivo, Inserm, CEA, Univ. Paris Sud, CNRS, Université Paris Saclay, CEA - Service Hospitalier Frédéric Joliot, Orsay, France
| | | | - Daniel Padro
- 3 Magnetic Resonance Imaging, CIC biomaGUNE, San Sebastian, Spain
| | - Raphaël Boisgard
- 1 Imagerie Moléculaire In Vivo, Inserm, CEA, Univ. Paris Sud, CNRS, Université Paris Saclay, CEA - Service Hospitalier Frédéric Joliot, Orsay, France
| | - Frédéric Dollé
- 1 Imagerie Moléculaire In Vivo, Inserm, CEA, Univ. Paris Sud, CNRS, Université Paris Saclay, CEA - Service Hospitalier Frédéric Joliot, Orsay, France
| | - Jordi Llop
- 2 Radiochemistry and Nuclear Imaging, CIC biomaGUNE, San Sebastian, Spain
| | - Alexandra Winkeler
- 1 Imagerie Moléculaire In Vivo, Inserm, CEA, Univ. Paris Sud, CNRS, Université Paris Saclay, CEA - Service Hospitalier Frédéric Joliot, Orsay, France
| | - Abraham Martín
- 4 Molecular Imaging Unit, CIC biomaGUNE, San Sebastian, Spain
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36
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Volkow ND, Wiers CE, Shokri-Kojori E, Tomasi D, Wang GJ, Baler R. Neurochemical and metabolic effects of acute and chronic alcohol in the human brain: Studies with positron emission tomography. Neuropharmacology 2017; 122:175-188. [PMID: 28108358 DOI: 10.1016/j.neuropharm.2017.01.012] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 12/20/2016] [Accepted: 01/14/2017] [Indexed: 02/07/2023]
Abstract
The use of Positron emission tomography (PET) to study the effects of acute and chronic alcohol on the human brain has enhanced our understanding of the mechanisms underlying alcohol's rewarding effects, the neuroadaptations from chronic exposure that contribute to tolerance and withdrawal, and the changes in fronto-striatal circuits that lead to loss of control and enhanced motivation to drink that characterize alcohol use disorders (AUD). These include studies showing that alcohol's reinforcing effects may result not only from its enhancement of dopaminergic, GABAergic and opioid signaling but also from its caloric properties. Studies in those suffering from an AUD have revealed significant alterations in dopamine (DA), GABA, cannabinoids, opioid and serotonin neurotransmission and in brain energy utilization (glucose and acetate metabolism) that are likely to contribute to compulsive alcohol taking, dysphoria/depression, and to alcohol-associated neurotoxicity. Studies have also evaluated the effects of abstinence on recovery of brain metabolism and neurotransmitter function and the potential value of some of these measures to predict clinical outcomes. Finally, PET studies have started to provide insights about the neuronal mechanisms by which certain genes contribute to the vulnerability to AUD. These findings have helped identify new strategies for prevention and treatment of AUD. This article is part of the Special Issue entitled "Alcoholism".
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Affiliation(s)
- Nora D Volkow
- National Institute on Drug Abuse, National Institutes of Health, Bethesda, MD 20892, United States; National Institute on Alcohol Abuse and Alcoholism, Laboratory of Neuroimaging, National Institutes of Health, Bethesda, MD 20892, United States.
| | - Corinde E Wiers
- National Institute on Drug Abuse, National Institutes of Health, Bethesda, MD 20892, United States
| | - Ehsan Shokri-Kojori
- National Institute on Drug Abuse, National Institutes of Health, Bethesda, MD 20892, United States
| | - Dardo Tomasi
- National Institute on Drug Abuse, National Institutes of Health, Bethesda, MD 20892, United States
| | - Gene-Jack Wang
- National Institute on Drug Abuse, National Institutes of Health, Bethesda, MD 20892, United States
| | - Ruben Baler
- National Institute on Alcohol Abuse and Alcoholism, Laboratory of Neuroimaging, National Institutes of Health, Bethesda, MD 20892, United States
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37
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Neuroimaging. IMAGING INFECTIONS 2017. [PMCID: PMC7123586 DOI: 10.1007/978-3-319-54592-9_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Imaging of infection in the CNS has been handled using cross-sectional imaging for more than two decades now resulting in a large array of descriptive diagnostic criteria, capable, in most circumstances of narrowing the differential diagnosis, detecting life-threatening complications and establishing baseline for assessment of treatment response. Limitations however exist, and in many circumstances, both cross-sectional imaging and nonspecific molecular imaging, such as 18F-FDG, fail to establish a diagnosis. The availability of pathogen-specific imaging agents/ligands would have a great effect on the management of patients with CNS infection. Besides early diagnosis, avoidance of diagnostic brain biopsies can have significant effect on the mortality and morbidity of patients.
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38
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Positron emission tomography in amyotrophic lateral sclerosis: Towards targeting of molecular pathological hallmarks. Eur J Nucl Med Mol Imaging 2016; 44:533-547. [DOI: 10.1007/s00259-016-3587-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 11/23/2016] [Indexed: 12/18/2022]
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Navarro G, Morales P, Rodríguez-Cueto C, Fernández-Ruiz J, Jagerovic N, Franco R. Targeting Cannabinoid CB2 Receptors in the Central Nervous System. Medicinal Chemistry Approaches with Focus on Neurodegenerative Disorders. Front Neurosci 2016; 10:406. [PMID: 27679556 PMCID: PMC5020102 DOI: 10.3389/fnins.2016.00406] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 08/22/2016] [Indexed: 12/04/2022] Open
Abstract
Endocannabinoids activate two types of specific G-protein-coupled receptors (GPCRs), namely cannabinoid CB1 and CB2. Contrary to the psychotropic actions of agonists of CB1 receptors, and serious side effects of the selective antagonists of this receptor, drugs acting on CB2 receptors appear as promising drugs to combat CNS diseases (Parkinson's disease, Huntington's chorea, cerebellar ataxia, amyotrohic lateral sclerosis). Differential localization of CB2 receptors in neural cell types and upregulation in neuroinflammation are keys to understand the therapeutic potential in inter alia diseases that imply progressive neurodegeneration. Medicinal chemistry approaches are now engaged to develop imaging tools to map receptors in the living human brain, to develop more efficacious agonists, and to investigate the possibility to develop allosteric modulators.
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Affiliation(s)
- Gemma Navarro
- Department of Biochemistry and Molecular Biomedicine, University of BarcelonaBarcelona, Spain; Centro de Investigación en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos IIIMadrid, Spain; Cell and Molecular Neuropharmacology, Institut de Biomedicina (IBUB), Universitat de BarcelonaBarcelona, Spain
| | - Paula Morales
- Instituto de Química Médica, Consejo Superior de Investigaciones CientíficasMadrid, Spain; Center for Drug Discovery, University of North Carolina at GreensboroGreensboro, NC, USA
| | - Carmen Rodríguez-Cueto
- Centro de Investigación en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos IIIMadrid, Spain; Departamento de Bioquímica, Facultad de Medicina, Instituto Universitario de Investigación en Neuroquímica, Universidad ComplutenseMadrid, Spain; Instituto Ramón y Cajal de Investigación SanitariaMadrid, Spain
| | - Javier Fernández-Ruiz
- Centro de Investigación en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos IIIMadrid, Spain; Departamento de Bioquímica, Facultad de Medicina, Instituto Universitario de Investigación en Neuroquímica, Universidad ComplutenseMadrid, Spain; Instituto Ramón y Cajal de Investigación SanitariaMadrid, Spain
| | - Nadine Jagerovic
- Instituto de Química Médica, Consejo Superior de Investigaciones Científicas Madrid, Spain
| | - Rafael Franco
- Department of Biochemistry and Molecular Biomedicine, University of BarcelonaBarcelona, Spain; Centro de Investigación en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos IIIMadrid, Spain; Cell and Molecular Neuropharmacology, Institut de Biomedicina (IBUB), Universitat de BarcelonaBarcelona, Spain
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Moldovan RP, Teodoro R, Gao Y, Deuther-Conrad W, Kranz M, Wang Y, Kuwabara H, Nakano M, Valentine H, Fischer S, Pomper MG, Wong DF, Dannals RF, Brust P, Horti AG. Development of a High-Affinity PET Radioligand for Imaging Cannabinoid Subtype 2 Receptor. J Med Chem 2016; 59:7840-55. [PMID: 27500461 DOI: 10.1021/acs.jmedchem.6b00554] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Cannabinoid receptors type 2 (CB2) represent a target with increasing importance for neuroimaging due to its upregulation under various pathological conditions. Encouraged by preliminary results obtained with [(11)C](Z)-N-(3-(2-methoxyethyl)-4,5-dimethylthiazol-2(3H)-ylidene)-2,2,3,3-tetramethyl-cyclopropanecarboxamide ([(11)C]A-836339, [(11)C]1) in a mouse model of acute neuroinflammation (induced by lipopolysaccharide, LPS), we designed a library of fluorinated analogues aiming for an [(18)F]-labeled radiotracer with improved CB2 binding affinity and selectivity. Compound (Z)-N-(3-(4-fluorobutyl)-4,5-dimethylthiazol-2(3H)-ylidene)-2,2,3,3-tetramethyl-cyclopropanecarboxamide (29) was selected as the ligand with the highest CB2 affinity (Ki = 0.39 nM) and selectivity over those of CB1 (factor of 1000). [(18)F]29 was prepared starting from the bromo precursor (53). Specific binding was shown in vitro, whereas fast metabolism was observed in vivo in CD-1 mice. Animal PET revealed a brain uptake comparable to that of [(11)C]1. In the LPS-treated mice, a 20-30% higher uptake in brain was found in comparison to that in nontreated mice (n = 3, P < 0.05).
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Affiliation(s)
- Rareş-Petru Moldovan
- Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Radiopharmaceutical Cancer Research , Leipzig, Germany
| | - Rodrigo Teodoro
- Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Radiopharmaceutical Cancer Research , Leipzig, Germany
| | - Yongjun Gao
- Johns Hopkins School of Medicine , Department of Radiology, Baltimore, 21287 United States
| | - Winnie Deuther-Conrad
- Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Radiopharmaceutical Cancer Research , Leipzig, Germany
| | - Mathias Kranz
- Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Radiopharmaceutical Cancer Research , Leipzig, Germany
| | - Yuchuan Wang
- Johns Hopkins School of Medicine , Department of Radiology, Baltimore, 21287 United States
| | - Hiroto Kuwabara
- Johns Hopkins School of Medicine , Department of Radiology, Baltimore, 21287 United States
| | - Masayoshi Nakano
- Johns Hopkins School of Medicine , Department of Radiology, Baltimore, 21287 United States
| | - Heather Valentine
- Johns Hopkins School of Medicine , Department of Radiology, Baltimore, 21287 United States
| | - Steffen Fischer
- Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Radiopharmaceutical Cancer Research , Leipzig, Germany
| | - Martin G Pomper
- Johns Hopkins School of Medicine , Department of Radiology, Baltimore, 21287 United States
| | - Dean F Wong
- Johns Hopkins School of Medicine , Department of Radiology, Baltimore, 21287 United States
| | - Robert F Dannals
- Johns Hopkins School of Medicine , Department of Radiology, Baltimore, 21287 United States
| | - Peter Brust
- Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Radiopharmaceutical Cancer Research , Leipzig, Germany
| | - Andrew G Horti
- Johns Hopkins School of Medicine , Department of Radiology, Baltimore, 21287 United States
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Ahmad R, Postnov A, Bormans G, Versijpt J, Vandenbulcke M, Van Laere K. Decreased in vivo availability of the cannabinoid type 2 receptor in Alzheimer’s disease. Eur J Nucl Med Mol Imaging 2016; 43:2219-2227. [DOI: 10.1007/s00259-016-3457-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 07/01/2016] [Indexed: 10/21/2022]
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Leurquin-Sterk G, Celen S, Van Laere K, Koole M, Bormans G, Langlois X, Van Hecken A, te Riele P, Alcázar J, Verbruggen A, de Hoon J, Andrés JI, Schmidt ME. What We Observe In Vivo Is Not Always What We See In Vitro: Development and Validation of 11C-JNJ-42491293, A Novel Radioligand for mGluR2. J Nucl Med 2016; 58:110-116. [DOI: 10.2967/jnumed.116.176628] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 07/11/2016] [Indexed: 12/13/2022] Open
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43
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Abstract
Microglial activation is a key aspect of the neuroinflammatory process in neurodegenerative disorders including idiopathic and atypical parkinsonian disorders. With positron emission tomography (PET) it has become possible to image this phenomenon in vivo and over the last years patterns of microglia activation corresponding with the known distribution of neuropathological changes in these disorders have been demonstrated using this technique. In addition the effects of interventions aimed at suppressing microglia activation as part of interventional trials have successfully been demonstrated. Current research aims at evaluating PET tracers for microglial activation with more favorable properties than the prototypical [11C]-(R)-PK11195, as well as developing tracers targeting additional parameters of the neuroinflammatory process like astroglial function.
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Affiliation(s)
- Alexander Gerhard
- Wolfson Molecular Imaging Centre, Institute of Brain, Behaviour and Mental Health, The University of Manchester, 27 Palatine Road, Withington, Manchester, M20 3LJ UK
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44
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Alterations in the Medullary Endocannabinoid System Contribute to Age-related Impairment of Baroreflex Sensitivity. J Cardiovasc Pharmacol 2016; 65:473-9. [PMID: 25636077 DOI: 10.1097/fjc.0000000000000216] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
As they age, Sprague-Dawley (SD) rats develop elevated systolic blood pressure associated with impaired baroreflex sensitivity (BRS) for control of heart rate. We previously demonstrated in young hypertensive (mRen2)27 rats that impaired BRS is restored by CB1 cannabinoid receptor blockade in the solitary tract nucleus (NTS), consistent with elevated content of the endocannabinoid 2-arachidonoylglycerol (2-AG) in dorsal medulla relative to normotensive SD rats. There is no effect of CB1 receptor blockade in young SD rats. We now report in older SD rats that dorsal medullary 2-AG levels are 2-fold higher at 70 versus 15 weeks of age (4.22 ± 0.61 vs. 1.93 ± 0.22 ng/mg tissue; P < 0.05). Furthermore, relative expression of CB1 receptor messenger RNA is significantly lower in aged rats, whereas CB2 receptor messenger RNA is significantly higher. In contrast to young adult SD rats, microinjection of the CB1 receptor antagonist SR141716A (36 pmole) into the NTS of older SD rats normalized BRS in animals exhibiting impaired baseline BRS (0.56 ± 0.06 baseline vs. 1.06 ± 0.05 ms/mm Hg after 60 minutes; P < 0.05). Therefore, this study provides evidence for alterations in the endocannabinoid system within the NTS of older SD rats that contribute to age-related impairment of BRS.
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45
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Comparison of dosimetry between PET/CT and PET alone using 11C-ITMM. AUSTRALASIAN PHYSICAL & ENGINEERING SCIENCES IN MEDICINE 2016; 39:177-86. [DOI: 10.1007/s13246-015-0419-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Accepted: 12/21/2015] [Indexed: 02/04/2023]
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46
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Janssen B, Vugts DJ, Funke U, Molenaar GT, Kruijer PS, van Berckel BNM, Lammertsma AA, Windhorst AD. Imaging of neuroinflammation in Alzheimer's disease, multiple sclerosis and stroke: Recent developments in positron emission tomography. Biochim Biophys Acta Mol Basis Dis 2015; 1862:425-41. [PMID: 26643549 DOI: 10.1016/j.bbadis.2015.11.011] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 10/09/2015] [Accepted: 11/19/2015] [Indexed: 12/13/2022]
Abstract
Neuroinflammation is thought to play a pivotal role in many diseases affecting the brain, including Alzheimer's disease, multiple sclerosis and stroke. Neuroinflammation is characterised predominantly by microglial activation, which can be visualised using positron emission tomography (PET). Traditionally, translocator protein 18kDa (TSPO) is the target for imaging of neuroinflammation using PET. In this review, recent preclinical and clinical research using PET in Alzheimer's disease, multiple sclerosis and stroke is summarised. In addition, new molecular targets for imaging of neuroinflammation, such as monoamine oxidases, adenosine receptors and cannabinoid receptor type 2, are discussed. This article is part of a Special Issue entitled: Neuro Inflammation edited by Helga E. de Vries and Markus Schwaninger.
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Affiliation(s)
- Bieneke Janssen
- Department of Radiology & Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands.
| | - Danielle J Vugts
- Department of Radiology & Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands
| | - Uta Funke
- Department of Radiology & Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands; BV Cyclotron VU, Amsterdam, The Netherlands
| | - Ger T Molenaar
- Department of Radiology & Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands; BV Cyclotron VU, Amsterdam, The Netherlands
| | | | - Bart N M van Berckel
- Department of Radiology & Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands
| | - Adriaan A Lammertsma
- Department of Radiology & Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands
| | - Albert D Windhorst
- Department of Radiology & Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands.
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Savonenko AV, Melnikova T, Wang Y, Ravert H, Gao Y, Koppel J, Lee D, Pletnikova O, Cho E, Sayyida N, Hiatt A, Troncoso J, Davies P, Dannals RF, Pomper MG, Horti AG. Cannabinoid CB2 Receptors in a Mouse Model of Aβ Amyloidosis: Immunohistochemical Analysis and Suitability as a PET Biomarker of Neuroinflammation. PLoS One 2015; 10:e0129618. [PMID: 26086915 PMCID: PMC4472959 DOI: 10.1371/journal.pone.0129618] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 05/11/2015] [Indexed: 11/18/2022] Open
Abstract
In Alzheimer's disease (AD), one of the early responses to Aβ amyloidosis is recruitment of microglia to areas of new plaque. Microglial receptors such as cannabinoid receptor 2 (CB2) might be a suitable target for development of PET radiotracers that could serve as imaging biomarkers of Aβ-induced neuroinflammation. Mouse models of amyloidosis (J20APPswe/ind and APPswe/PS1ΔE9) were used to investigate the cellular distribution of CB2 receptors. Specificity of CB2 antibody (H60) was confirmed using J20APPswe/ind mice lacking CB2 receptors. APPswe/PS1ΔE9 mice were used in small animal PET with a CB2-targeting radiotracer, [11C]A836339. These studies revealed increased binding of [11C]A836339 in amyloid-bearing mice. Specificity of the PET signal was confirmed in a blockade study with a specific CB2 antagonist, AM630. Confocal microscopy revealed that CB2-receptor immunoreactivity was associated with astroglial (GFAP) and, predominantly, microglial (CD68) markers. CB2 receptors were observed, in particular, in microglial processes forming engulfment synapses with Aβ plaques. In contrast to glial cells, neuron (NeuN)-derived CB2 signal was equal between amyloid-bearing and control mice. The pattern of neuronal CB2 staining in amyloid-bearing mice was similar to that in human cases of AD. The data collected in this study indicate that Aβ amyloidosis without concomitant tau pathology is sufficient to activate CB2 receptors that are suitable as an imaging biomarker of neuroinflammation. The main source of enhanced CB2 PET binding in amyloid-bearing mice is increased CB2 immunoreactivity in activated microglia. The presence of CB2 immunoreactivity in neurons does not likely contribute to the enhanced CB2 PET signal in amyloid-bearing mice due to a lack of significant neuronal loss in this model. However, significant loss of neurons as seen at late stages of AD might decrease the CB2 PET signal due to loss of neuronally-derived CB2. Thus this study in mouse models of AD indicates that a CB2-specific radiotracer can be used as a biomarker of neuroinflammation in the early preclinical stages of AD, when no significant neuronal loss has yet developed.
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Affiliation(s)
- Alena V. Savonenko
- Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
- Departments of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
- * E-mail: (AGH); (AS)
| | - Tatiana Melnikova
- Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
| | - Yuchuan Wang
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
| | - Hayden Ravert
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
| | - Yongjun Gao
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
| | - Jeremy Koppel
- Litwin-Zucker Research Center, Feinstein Institute for Medical Research, North-Shore Long Island Jewish Health System, Manhasset, NY, United States of America
| | - Deidre Lee
- Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
| | - Olga Pletnikova
- Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
| | - Eugenia Cho
- Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
| | - Nuzhat Sayyida
- Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
| | - Andrew Hiatt
- MAPP Biopharmaceutical Inc, San-Diego, CA, United States of America
| | - Juan Troncoso
- Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
- Departments of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
| | - Peter Davies
- Litwin-Zucker Research Center, Feinstein Institute for Medical Research, North-Shore Long Island Jewish Health System, Manhasset, NY, United States of America
| | - Robert F. Dannals
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
| | - Martin G. Pomper
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
| | - Andrew G. Horti
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
- * E-mail: (AGH); (AS)
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48
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Saccomanni G, Pascali G, Carlo SD, Panetta D, De Simone M, Bertini S, Burchielli S, Digiacomo M, Macchia M, Manera C, Salvadori PA. Design, synthesis and preliminary evaluation of (18)F-labelled 1,8-naphthyridin- and quinolin-2-one-3-carboxamide derivatives for PET imaging of CB2 cannabinoid receptor. Bioorg Med Chem Lett 2015; 25:2532-5. [PMID: 25956416 DOI: 10.1016/j.bmcl.2015.04.055] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 04/15/2015] [Accepted: 04/17/2015] [Indexed: 10/23/2022]
Abstract
In the present work, we report the synthesis of new aryliodonium salts used as precursors of single-stage nucleophilic (18)F radiofluorination. The corresponding unlabelled fluorinated derivatives showed to be CB2 cannabinoid receptor specific ligands, with Ki values in the low nanomolar range and high CB2/CB1 selectivity. The radiolabelled compound [(18)F]CB91, was successfully formulated for in vivo administration, and its preliminary biodistribution was assessed with microPET/CT. This tracer presented a reasonable in vivo stability and a preferential extraction in the tissues that constitutionally express CB2 cannabinoid receptor. The results obtained indicate [(18)F]CB91 as a possible candidate marker of CB2 cannabinoid receptor distribution. This study would open the way to further validation of this tracer for assessing pathologies for which the expression of this receptor is modified.
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Affiliation(s)
- Giuseppe Saccomanni
- Dipartimento di Farmacia, Università di Pisa, Via Bonanno 6, 56126 Pisa, Italy
| | - Giancarlo Pascali
- CNR Istituto di Fisiologia Clinica, Via Moruzzi, 1, 56124 Pisa, Italy; ANSTO LifeSciences, PO Box M34, Camperdown 2050, Australia
| | - Sara Del Carlo
- Dipartimento di Farmacia, Università di Pisa, Via Bonanno 6, 56126 Pisa, Italy
| | - Daniele Panetta
- CNR Istituto di Fisiologia Clinica, Via Moruzzi, 1, 56124 Pisa, Italy
| | | | - Simone Bertini
- Dipartimento di Farmacia, Università di Pisa, Via Bonanno 6, 56126 Pisa, Italy
| | | | - Maria Digiacomo
- Dipartimento di Farmacia, Università di Pisa, Via Bonanno 6, 56126 Pisa, Italy
| | - Marco Macchia
- Dipartimento di Farmacia, Università di Pisa, Via Bonanno 6, 56126 Pisa, Italy
| | - Clementina Manera
- Dipartimento di Farmacia, Università di Pisa, Via Bonanno 6, 56126 Pisa, Italy.
| | - Piero A Salvadori
- CNR Istituto di Fisiologia Clinica, Via Moruzzi, 1, 56124 Pisa, Italy
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49
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Hammers A. Diagnostica per immagini cerebrale tramite tomografia a emissione di positroni in neurologia: dalla misurazione del flusso sanguigno e del metabolismo all’esplorazione della neurotrasmissione. Neurologia 2015. [DOI: 10.1016/s1634-7072(15)70502-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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50
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Slavik R, Herde AM, Bieri D, Weber M, Schibli R, Krämer SD, Ametamey SM, Mu L. Synthesis, radiolabeling and evaluation of novel 4-oxo-quinoline derivatives as PET tracers for imaging cannabinoid type 2 receptor. Eur J Med Chem 2015; 92:554-64. [DOI: 10.1016/j.ejmech.2015.01.028] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 01/10/2015] [Accepted: 01/12/2015] [Indexed: 10/24/2022]
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