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Knippenberg N, Bauwens M, Schijns O, Hoogland G, Florea A, Rijkers K, Cleij TJ, Eersels K, van Grinsven B, Diliën H. Visualizing GABA transporters in vivo: an overview of reported radioligands and future directions. EJNMMI Res 2023; 13:42. [PMID: 37171631 PMCID: PMC10182260 DOI: 10.1186/s13550-023-00992-5] [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: 03/23/2023] [Accepted: 05/02/2023] [Indexed: 05/13/2023] Open
Abstract
By clearing GABA from the synaptic cleft, GABA transporters (GATs) play an essential role in inhibitory neurotransmission. Consequently, in vivo visualization of GATs can be a valuable diagnostic tool and biomarker for various psychiatric and neurological disorders. Not surprisingly, in recent years several research attempts to develop a radioligand have been conducted, but so far none have led to suitable radioligands that allow imaging of GATs. Here, we provide an overview of the radioligands that were developed with a focus on GAT1, since this is the most abundant transporter and most of the research concerns this GAT subtype. Initially, we focus on the field of GAT1 inhibitors, after which we discuss the development of GAT1 radioligands based on these inhibitors. We hypothesize that the radioligands developed so far have been unsuccessful due to the zwitterionic nature of their nipecotic acid moiety. To overcome this problem, the use of non-classical GAT inhibitors as basis for GAT1 radioligands or the use of carboxylic acid bioisosteres may be considered. As the latter structural modification has already been used in the field of GAT1 inhibitors, this option seems particularly viable and could lead to the development of more successful GAT1 radioligands in the future.
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Affiliation(s)
- Niels Knippenberg
- Sensor Engineering Department, Faculty of Science and Engineering, Maastricht University, 6200 MD, Maastricht, The Netherlands.
| | - Matthias Bauwens
- Department of Nuclear Medicine, University Hospital Aachen, RWTH Aachen University, 52074, Aachen, Germany
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Centre+ (MUMC+), 6229 HX, Maastricht, The Netherlands
| | - Olaf Schijns
- Department of Neurosurgery, Maastricht University Medical Centre+ (MUMC+), 6229 HX, Maastricht, The Netherlands
- School for Mental Health and Neuroscience (MHeNS), Maastricht University, 6200 MD, Maastricht, The Netherlands
- Academic Center for Epileptology (ACE), Maastricht University Medical Centre+ (MUMC+), 6229 HX, Maastricht, The Netherlands
| | - Govert Hoogland
- Department of Neurosurgery, Maastricht University Medical Centre+ (MUMC+), 6229 HX, Maastricht, The Netherlands
- School for Mental Health and Neuroscience (MHeNS), Maastricht University, 6200 MD, Maastricht, The Netherlands
| | - Alexandru Florea
- Department of Nuclear Medicine, University Hospital Aachen, RWTH Aachen University, 52074, Aachen, Germany
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Centre+ (MUMC+), 6229 HX, Maastricht, The Netherlands
- School for Cardiovascular Diseases (CARIM), Maastricht University Medical Centre+ (MUMC+), 6229 HX, Maastricht, The Netherlands
| | - Kim Rijkers
- Department of Neurosurgery, Maastricht University Medical Centre+ (MUMC+), 6229 HX, Maastricht, The Netherlands
- School for Mental Health and Neuroscience (MHeNS), Maastricht University, 6200 MD, Maastricht, The Netherlands
- Academic Center for Epileptology (ACE), Maastricht University Medical Centre+ (MUMC+), 6229 HX, Maastricht, The Netherlands
| | - Thomas J Cleij
- Sensor Engineering Department, Faculty of Science and Engineering, Maastricht University, 6200 MD, Maastricht, The Netherlands
| | - Kasper Eersels
- Sensor Engineering Department, Faculty of Science and Engineering, Maastricht University, 6200 MD, Maastricht, The Netherlands
| | - Bart van Grinsven
- Sensor Engineering Department, Faculty of Science and Engineering, Maastricht University, 6200 MD, Maastricht, The Netherlands
| | - Hanne Diliën
- Sensor Engineering Department, Faculty of Science and Engineering, Maastricht University, 6200 MD, Maastricht, The Netherlands
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Yuan G, Dhaynaut M, Lan Y, Guehl NJ, Huynh D, Iyengar SM, Afshar S, Jain MK, Pickett JE, Kang HJ, Wang H, Moon SH, Ondrechen MJ, Wang C, Shoup TM, El Fakhri G, Normandin MD, Brownell AL. Synthesis and Characterization of 5-(2-Fluoro-4-[ 11C]methoxyphenyl)-2,2-dimethyl-3,4-dihydro-2 H-pyrano[2,3- b]pyridine-7-carboxamide as a PET Imaging Ligand for Metabotropic Glutamate Receptor 2. J Med Chem 2022; 65:2593-2609. [PMID: 35089713 PMCID: PMC9434702 DOI: 10.1021/acs.jmedchem.1c02004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Metabotropic glutamate receptor 2 (mGluR2) is a therapeutic target for several neuropsychiatric disorders. An mGluR2 function in etiology could be unveiled by positron emission tomography (PET). In this regard, 5-(2-fluoro-4-[11C]methoxyphenyl)-2,2-dimethyl-3,4-dihydro-2H-pyrano[2,3-b]pyridine-7-carboxamide ([11C]13, [11C]mG2N001), a potent negative allosteric modulator (NAM), was developed to support this endeavor. [11C]13 was synthesized via the O-[11C]methylation of phenol 24 with a high molar activity of 212 ± 76 GBq/μmol (n = 5) and excellent radiochemical purity (>99%). PET imaging of [11C]13 in rats demonstrated its superior brain heterogeneity and reduced accumulation with pretreatment of mGluR2 NAMs, VU6001966 (9) and MNI-137 (26), the extent of which revealed a time-dependent drug effect of the blocking agents. In a nonhuman primate, [11C]13 selectively accumulated in mGluR2-rich regions and resulted in high-contrast brain images. Therefore, [11C]13 is a potential candidate for translational PET imaging of the mGluR2 function.
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Affiliation(s)
- Gengyang Yuan
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Maeva Dhaynaut
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Yu Lan
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Nicolas J Guehl
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Dalena Huynh
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Suhasini M Iyengar
- Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Sepideh Afshar
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Manish Kumar Jain
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Julie E Pickett
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Hye Jin Kang
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Hao Wang
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Sung-Hyun Moon
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Mary Jo Ondrechen
- Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Changning Wang
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Timothy M Shoup
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Georges El Fakhri
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Marc D Normandin
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Anna-Liisa Brownell
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
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3
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Yuan G, Guehl NJ, Zheng B, Qu X, Moon SH, Dhaynaut M, Shoup TM, Afshar S, Kang HJ, Zhang Z, El Fakhri G, Normandin MD, Brownell AL. Synthesis and Characterization of [ 18F]JNJ-46356479 as the First 18F-Labeled PET Imaging Ligand for Metabotropic Glutamate Receptor 2. Mol Imaging Biol 2021; 23:527-536. [PMID: 33559035 DOI: 10.1007/s11307-021-01586-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 01/11/2021] [Accepted: 01/27/2021] [Indexed: 02/07/2023]
Abstract
PURPOSE Metabotropic glutamate receptor 2 (mGluR2) has been implicated in various psychiatric and neurological disorders, such as schizophrenia and Alzheimer's disease. We have previously developed [11C]7 as a PET radioligand for imaging mGluR2. Herein, [18F]JNJ-46356479 ([18F]8) was synthesized and characterized as the first 18F-labeled mGluR2 imaging ligand to enhance diagnostic approaches for mGluR2-related disorders. PROCEDURES JNJ-46356479 (8) was radiolabeled via the copper (I)-mediated radiofluorination of organoborane 9. In vivo PET imaging experiments with [18F]8 were conducted first in C57BL/6 J mice and Sprague-Dawley rats to obtain whole body biodistribution and brain uptake profile. Subsequent PET studies were done in a cynomolgus monkey (Macaca fascicularis) to investigate the uptake of [18F]8 in the brain, its metabolic stability, as well as pharmacokinetic properties. RESULTS JNJ-46356479 (8) exhibited excellent selectivity against other mGluRs. In vivo PET imaging studies showed reversible and specific binding characteristic of [18F]8 in rodents. In the non-human primate, [18F]8 displayed good in vivo metabolic stability, excellent brain permeability, fast and reversible kinetics with moderate heterogeneity across brain regions. Pre-treatment studies with compound 7 revealed time-dependent decrease of [18F]8 accumulation in mGluR2 rich regions based on SUV values with the highest decrease in the nucleus accumbens (18.7 ± 5.9%) followed by the cerebellum (18.0 ± 7.9%), the parietal cortex (16.9 ± 7.8%), and the hippocampus (16.8 ± 6.9%), similar to results obtained in the rat studies. However, the volume of distribution (VT) results derived from 2T4k model showed enhanced VT from a blocking study with compound 7. This is probably because of the potentiating effect of compound 7 as an mGluR2 PAM as well as related non-specific binding in the tissue data. CONCLUSIONS [18F]8 readily crosses the blood-brain barrier and demonstrates fast and reversible kinetics both in rodents and in a non-human primate. Further investigation of [18F]8 on its binding specificity would warrant translational study in human.
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Affiliation(s)
- Gengyang Yuan
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, MA, 02129, USA.
| | - Nicolas J Guehl
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, MA, 02129, USA
| | - Baohui Zheng
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, MA, 02129, USA
| | - Xiying Qu
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, MA, 02129, USA
| | - Sung-Hyun Moon
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, MA, 02129, USA
| | - Maeva Dhaynaut
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, MA, 02129, USA
| | - Timothy M Shoup
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, MA, 02129, USA
| | - Sepideh Afshar
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, MA, 02129, USA
| | - Hye Jin Kang
- Department of Pharmacology, University of North Carolina Chapel Hill School of Medicine, Chapel Hill, NC, 27514, USA
| | - Zhaoda Zhang
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, MA, 02129, USA
| | - Georges El Fakhri
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, MA, 02129, USA
| | - Marc D Normandin
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, MA, 02129, USA
| | - Anna-Liisa Brownell
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, MA, 02129, USA.
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Kumata K, Zhang Y, Ogawa M, Kurihara Y, Mori W, Hu K, Fujinaga M, Nengaki N, Zhang MR. 3-(Cyclopropylmethyl)-7-((4-(4-[ 11C]methoxyphenyl)piperidin-1-yl)methyl)-8-(trifluoromethyl)-[1,2,4]triazolo[4,3-a]pyridine: Synthesis and preliminary evaluation for PET imaging of metabotropic glutamate receptor subtype 2. Bioorg Med Chem Lett 2020; 30:127555. [PMID: 32941990 DOI: 10.1016/j.bmcl.2020.127555] [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: 07/28/2020] [Revised: 09/06/2020] [Accepted: 09/11/2020] [Indexed: 10/23/2022]
Abstract
Selective metabotropic glutamate receptor 2 (mGluR2) inhibitors have been demonstrated to show therapeutic effects by improving alleviating symptoms of schizophrenic patients in clinical studies. Herein we report the synthesis and preliminary evaluation of a 11C-labeled positron emission tomography (PET) tracer originating from a mGluR2 inhibitor, 3-(cyclopropylmethyl)-7-((4-(4-methoxyphenyl)piperidin-1-yl)methyl)-8-(trifluoromethyl)-[1,2,4]triazolo[4,3-a]pyridine (CMTP, 1a). [11C]CMTP ([11C]1a) was synthesized by O-[11C]methylation of desmethyl precursor 1b with [11C]methyl iodide in 19.7 ± 8.9% (n = 10) radiochemical yield (based on [11C]CO2) with >98% radiochemical purity and >74 GBq/μmol molar activity. Autoradiography study showed that [11C]1a possessed moderate in vitro specific binding to mGluR2 in the rat brain, with a heterogeneous distribution of radioactive accumulation in the mGluR2-rich brain tissue sections, such as the cerebral cortex and striatum. PET study indicated that [11C]1a was able to cross the blood-brain barrier and enter the brain, but had very low specific binding in the rat brain. Further optimization for the chemical structure of 1a is necessary to increase binding affinity to mGluR2 and then improve in vivo specific binding in brain.
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Affiliation(s)
- Katsushi Kumata
- Department of Advanced Nuclear Medicine Sciences, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Yiding Zhang
- Department of Advanced Nuclear Medicine Sciences, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Masanao Ogawa
- Department of Advanced Nuclear Medicine Sciences, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan; SHI Accelerator Service, Ltd, 1-17-6 Osaki, Shinagawa-ku, Tokyo 141-0032, Japan
| | - Yusuke Kurihara
- Department of Advanced Nuclear Medicine Sciences, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan; SHI Accelerator Service, Ltd, 1-17-6 Osaki, Shinagawa-ku, Tokyo 141-0032, Japan
| | - Wakana Mori
- Department of Advanced Nuclear Medicine Sciences, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Kuan Hu
- Department of Advanced Nuclear Medicine Sciences, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Masayuki Fujinaga
- Department of Advanced Nuclear Medicine Sciences, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Nobuki Nengaki
- Department of Advanced Nuclear Medicine Sciences, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan; SHI Accelerator Service, Ltd, 1-17-6 Osaki, Shinagawa-ku, Tokyo 141-0032, Japan
| | - Ming-Rong Zhang
- Department of Advanced Nuclear Medicine Sciences, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan.
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5
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Yuan G, Qu X, Zheng B, Neelamegam R, Afshar S, Iyengar S, Pan C, Wang J, Kang HJ, Ondrechen MJ, Poutiainen P, El Fakhri G, Zhang Z, Brownell AL. Design, Synthesis, and Characterization of Benzimidazole Derivatives as Positron Emission Tomography Imaging Ligands for Metabotropic Glutamate Receptor 2. J Med Chem 2020; 63:12060-12072. [PMID: 32981322 DOI: 10.1021/acs.jmedchem.0c01394] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Three benzimidazole derivatives (13-15) have been synthetized as potential positron emission tomography (PET) imaging ligands for mGluR2 in the brain. Of these compounds, 13 exhibits potent binding affinity (IC50 = 7.6 ± 0.9 nM), positive allosteric modulator (PAM) activity (EC50 = 51.2 nM), and excellent selectivity against other mGluR subtypes (>100-fold). [11C]13 was synthesized via O-[11C]methylation of its phenol precursor 25 with [11C]methyl iodide. The achieved radiochemical yield was 20 ± 2% (n = 10, decay-corrected) based on [11C]CO2 with a radiochemical purity of >98% and molar activity of 98 ± 30 GBq/μmol EOS. Ex vivo biodistribution studies revealed reversible accumulation of [11C]13 and hepatobiliary and urinary excretions. PET imaging studies in rats demonstrated that [11C]13 accumulated in the mGluR2-rich brain regions. Pre-administration of mGluR2-selective PAM, 17 reduced the brain uptake of [11C]13, indicating a selective binding. Therefore, [11C]13 is a potential PET imaging ligand for mGluR2 in different central nervous system-related conditions.
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Affiliation(s)
- Gengyang Yuan
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Xiying Qu
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Baohui Zheng
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Ramesh Neelamegam
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Sepideh Afshar
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Suhasini Iyengar
- Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Chuzhi Pan
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Junfeng Wang
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Hye Jin Kang
- Department of Pharmacology, University of North Carolina Chapel Hill School of Medicine, Chapel Hill, North Carolina 27514, United States
| | - Mary Jo Ondrechen
- Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Pekka Poutiainen
- Department of Clinical Physiology and Nuclear Medicine, Kuopio University Hospital, Kuopio 70210, Finland
| | - Georges El Fakhri
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
| | - Zhaoda Zhang
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129, United States
| | - Anna-Liisa Brownell
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, 3rd Avenue, Charlestown, Massachusetts 02129, United States
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6
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Zhang X, Zhang Y, Chen Z, Shao T, Van R, Kumata K, Deng X, Fu H, Yamasaki T, Rong J, Hu K, Hatori A, Xie L, Yu Q, Ye W, Xu H, Sheffler DJ, Cosford NDP, Shao Y, Tang P, Wang L, Zhang MR, Liang SH. Synthesis and preliminary studies of 11C-labeled tetrahydro-1,7-naphthyridine-2-carboxamides for PET imaging of metabotropic glutamate receptor 2. Theranostics 2020; 10:11178-11196. [PMID: 33042277 PMCID: PMC7532674 DOI: 10.7150/thno.42587] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 08/19/2020] [Indexed: 12/21/2022] Open
Abstract
Selective modulation of metabotropic glutamate receptor 2 (mGlu2) represents a novel therapeutic approach for treating brain disorders, including schizophrenia, depression, Parkinson's disease (PD), Alzheimer's disease (AD), drug abuse and addiction. Imaging mGlu2 using positron emission tomography (PET) would allow for in vivo quantification under physiological and pathological conditions and facilitate drug discovery by enabling target engagement studies. In this paper, we aimed to develop a novel specific radioligand derived from negative allosteric modulators (NAMs) for PET imaging of mGlu2. Methods. A focused small molecule library of mGlu2 NAMs with tetrahydro naphthyridine scaffold was synthesized for pharmacology and physicochemical evaluation. GIRK dose-response assays and CNS panel binding selectivity assays were performed to study the affinity and selectivity of mGlu2 NAMs, among which compounds 14a and 14b were selected as PET ligand candidates. Autoradiography in SD rat brain sections was used to confirm the in vitro binding specificity and selectivity of [11C]14a and [11C]14b towards mGlu2. In vivo binding specificity was then studied by PET imaging. Whole body biodistribution study and radiometabolite analysis were conducted to demonstrate the pharmacokinetic properties of [11C]14b as most promising PET mGlu2 PET ligand. Results. mGlu2 NAMs 14a-14g were synthesized in 14%-20% yields in five steps. NAMs 14a and 14b were selected to be the most promising ligands due to their high affinity in GIRK dose-response assays. [11C]14a and [11C]14b displayed similar heterogeneous distribution by autoradiography, consistent with mGlu2 expression in the brain. While PET imaging study showed good brain permeability for both tracers, compound [11C]14b demonstrated superior binding specificity compared to [11C]14a. Further radiometabolite analysis of [11C]14b showed excellent stability in the brain. Conclusions. Compound 14b exhibited high affinity and excellent subtype selectivity, which was then evaluated by in vitro autoradiography and in vivo PET imaging study after labeling with carbon-11. Ligand [11C]14b, which we named [11C]MG2-1904, demonstrated high brain uptake and excellent in vitro/in vivo specific binding towards mGlu2 with high metabolic stability in the brain. As proof-of-concept, our preliminary work demonstrated a successful example of visualizing mGlu2in vivo derived from NAMs, which represents a promising chemotype for further development and optimization aimed for clinical translation.
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Affiliation(s)
- Xiaofei Zhang
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, China
| | - Yiding Zhang
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Zhen Chen
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Tuo Shao
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Richard Van
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019, United States
| | - Katsushi Kumata
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Xiaoyun Deng
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Hualong Fu
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Tomoteru Yamasaki
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Jian Rong
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Kuan Hu
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Akiko Hatori
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Lin Xie
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Qingzhen Yu
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Weijian Ye
- Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, 613 West Huangpu Road, Tianhe District, Guangzhou 510630, China
| | - Hao Xu
- Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, 613 West Huangpu Road, Tianhe District, Guangzhou 510630, China
| | - Douglas J. Sheffler
- Cancer Metabolism and Signaling Networks Program and Conrad Prebys Center for Chemical Genomics, Sanford-Burnham Prebys Medical Discovery Institute, La Jolla, California 92037, United States
| | - Nicholas D. P. Cosford
- Cancer Metabolism and Signaling Networks Program and Conrad Prebys Center for Chemical Genomics, Sanford-Burnham Prebys Medical Discovery Institute, La Jolla, California 92037, United States
| | - Yihan Shao
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019, United States
| | - Pingping Tang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, China
| | - Lu Wang
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
- Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, 613 West Huangpu Road, Tianhe District, Guangzhou 510630, China
| | - Ming-Rong Zhang
- Department of Radiopharmaceuticals Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Steven H. Liang
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
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Xu Y, Li Z. Imaging metabotropic glutamate receptor system: Application of positron emission tomography technology in drug development. Med Res Rev 2019; 39:1892-1922. [DOI: 10.1002/med.21566] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Revised: 01/18/2019] [Accepted: 01/24/2019] [Indexed: 12/17/2022]
Affiliation(s)
- Youwen Xu
- Independent Consultant and Contractor, Radiopharmaceutical Development, Validation and Bio-Application; Philadelphia Pennsylvania
| | - Zizhong Li
- Pharmaceutical Research and Development, SOFIE Biosciences; Somerset New Jersey
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8
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Zhang X, Kumata K, Yamasaki T, Cheng R, Hatori A, Ma L, Zhang Y, Xie L, Wang L, Kang HJ, Sheffler DJ, Cosford NDP, Zhang MR, Liang SH. Synthesis and Preliminary Studies of a Novel Negative Allosteric Modulator, 7-((2,5-Dioxopyrrolidin-1-yl)methyl)-4-(2-fluoro-4-[ 11C]methoxyphenyl) quinoline-2-carboxamide, for Imaging of Metabotropic Glutamate Receptor 2. ACS Chem Neurosci 2017; 8:1937-1948. [PMID: 28565908 PMCID: PMC5607115 DOI: 10.1021/acschemneuro.7b00098] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Metabotropic glutamate 2 receptors (mGlu2) are involved in the pathogenesis of several CNS disorders and neurodegenerative diseases. Pharmacological modulation of this target represents a potential disease-modifying approach for the treatment of substance abuse, depression, schizophrenia, and dementias. While quantification of mGlu2 receptors in the living brain by positron emission tomography (PET) would help us better understand signaling pathways relevant to these conditions, few successful examples have been demonstrated to image mGlu2 in vivo, and a suitable PET tracer is yet to be identified. Herein we report the design and synthesis of a radiolabeled negative allosteric modulator (NAM) for mGlu2 PET tracer development based on a quinoline 2-carboxamide scaffold. The most promising candidate, 7-((2,5-dioxopyrrolidin-1-yl)methyl)-4-(2-fluoro-4-[11C]methoxyphenyl) quinoline-2-carboxamide ([11C]QCA) was prepared in 13% radiochemical yield (non-decay-corrected at the end of synthesis) with >99% radiochemical purity and >74 GBq/μmol (2 Ci/μmol) specific activity. While the tracer showed limited brain uptake (0.3 SUV), probably attributable to effects on PgP/Bcrp efflux pump, in vitro autoradiography studies demonstrated heterogeneous brain distribution and specific binding. Thus, [11C]QCA is a chemical probe that provides the basis for the development of a new generation mGlu2 PET tracers.
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MESH Headings
- ATP Binding Cassette Transporter, Subfamily G, Member 2/deficiency
- ATP Binding Cassette Transporter, Subfamily G, Member 2/genetics
- Adhesins, Escherichia coli
- Allosteric Regulation
- Animals
- Autoradiography
- Brain/diagnostic imaging
- Brain/metabolism
- Drug Design
- Humans
- Magnetic Resonance Imaging
- Male
- Mice, Knockout
- Mice, Mutant Strains
- Microsomes, Liver/drug effects
- Microsomes, Liver/metabolism
- Molecular Structure
- Positron-Emission Tomography
- Preliminary Data
- Pyrrolidines/chemistry
- Quinolines/chemistry
- Radiopharmaceuticals/chemical synthesis
- Rats, Sprague-Dawley
- Receptors, Metabotropic Glutamate/metabolism
- Tissue Distribution
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Affiliation(s)
- Xiaofei Zhang
- Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Collaborative Innovation Center of Chemical Science and Engineering, Nankai Unviersity, Tianjin 300071, China
| | - Katsushi Kumata
- Department of Radiopharmaceutics Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Tomoteru Yamasaki
- Department of Radiopharmaceutics Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Ran Cheng
- Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Akiko Hatori
- Department of Radiopharmaceutics Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Longle Ma
- Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Yiding Zhang
- Department of Radiopharmaceutics Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Lin Xie
- Department of Radiopharmaceutics Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Lu Wang
- Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
| | - Hye Jin Kang
- Department of Pharmacology & National Institute of Mental Health Psychoactive Drug Screening Program, University of North Carolina at Chapel Hill, North Carolina, 27515, USA
| | - Douglas J. Sheffler
- Cell Death and Survival Networks Program and Conrad Prebys Center for Chemical Genomics, Sanford-Burnham Medical Research Institute, La Jolla, CA, 92037, USA
| | - Nicholas D. P. Cosford
- Cell Death and Survival Networks Program and Conrad Prebys Center for Chemical Genomics, Sanford-Burnham Medical Research Institute, La Jolla, CA, 92037, USA
| | - Ming-Rong Zhang
- Department of Radiopharmaceutics Development, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Steven H. Liang
- Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA, 02114, USA
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9
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Kumata K, Yamasaki T, Hatori A, Zhang Y, Mori W, Fujinaga M, Xie L, Okubo T, Nengaki N, Zhang MR. Synthesis and in vitro evaluation of three novel radiotracers for imaging of metabotropic glutamate receptor subtype 2 in rat brain. Bioorg Med Chem Lett 2017; 27:3139-3143. [DOI: 10.1016/j.bmcl.2017.05.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Revised: 05/08/2017] [Accepted: 05/10/2017] [Indexed: 11/30/2022]
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10
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Ma Y, Kumata K, Yui J, Zhang Y, Yamasaki T, Hatori A, Fujinaga M, Nengaki N, Xie L, Wang H, Zhang MR. Synthesis and evaluation of 1-(cyclopropylmethyl)-4-(4-[ 11 C]methoxyphenyl)-piperidin-1-yl-2-oxo-1,2-dihydropyridine-3-carbonitrile ([ 11 C]CMDC) for PET imaging of metabotropic glutamate receptor 2 in the rat brain. Bioorg Med Chem 2017; 25:1014-1021. [DOI: 10.1016/j.bmc.2016.12.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 11/29/2016] [Accepted: 12/08/2016] [Indexed: 10/20/2022]
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11
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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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12
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Poutiainen P, Kil KE, Zhang Z, Kuruppu D, Tannous B, Brownell AL. Co-operative binding assay for the characterization of mGlu4 allosteric modulators. Neuropharmacology 2015; 97:142-8. [PMID: 26025660 DOI: 10.1016/j.neuropharm.2015.05.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 05/06/2015] [Accepted: 05/11/2015] [Indexed: 11/25/2022]
Abstract
The interest in the role of metabotropic glutamate receptor 4 (mGlu4) in CNS related disorders has increased the need for methods to investigate the binding of allosteric drug candidates. Our aim is to present the first fully characterized in vitro binding assay of mGlu4 positive allosteric modulators (PAMs). Results suggest that mGlu4 PAMs have characteristic co-operative binding with orthosteric glutamate, which offers a notable insight to the further development of mGlu4 targeted therapies.
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Affiliation(s)
- Pekka Poutiainen
- Athinoula A. Martinos Biomedical Imaging Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Kun-Eek Kil
- Athinoula A. Martinos Biomedical Imaging Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Zhaoda Zhang
- Athinoula A. Martinos Biomedical Imaging Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Darshini Kuruppu
- Division of Surgical Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Bakhos Tannous
- Experimental Therapeutics and Molecular Imaging Laboratory, Neuroscience Center, Department of Neurology, Massachusetts General Hospital, Boston, MA, USA; Program in Neuroscience, Harvard Medical School, Boston, MA, USA
| | - Anna-Liisa Brownell
- Athinoula A. Martinos Biomedical Imaging Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
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13
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Janssen B, Vugts DJ, Funke U, Spaans A, Schuit RC, Kooijman E, Rongen M, Perk LR, Lammertsma AA, Windhorst AD. Synthesis and initial preclinical evaluation of the P2X7 receptor antagonist [¹¹C]A-740003 as a novel tracer of neuroinflammation. J Labelled Comp Radiopharm 2014; 57:509-16. [PMID: 24995673 DOI: 10.1002/jlcr.3206] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 04/09/2014] [Accepted: 04/11/2014] [Indexed: 11/10/2022]
Abstract
Neuroinflammation, in particular activation of microglia, is thought to play an important role in the progression of neurodegenerative diseases. In activated microglia, the purinergic P2X7 receptor is upregulated. A-740003, a highly affine and selective P2X7 receptor antagonist, is a promising candidate for the development of a radiotracer for imaging of neuroinflammation by positron emission tomography. For this purpose, [(11)C]A-740003 was synthesised and evaluated in vivo with respect to both tracer metabolism and biodistribution. In plasma, a moderate metabolic rate was seen. In healthy rat brain, only marginal uptake of [(11)C]A-740003 was observed and, therefore, metabolites in brain could not be determined. Whether the minimal brain uptake is due to the low expression levels of the P2X7 receptor in healthy brain or to limited transport across the blood-brain barrier has yet to be elucidated.
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Affiliation(s)
- Bieneke Janssen
- Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands
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Kim E, Howes OD, Kapur S. Molecular imaging as a guide for the treatment of central nervous system disorders. DIALOGUES IN CLINICAL NEUROSCIENCE 2014. [PMID: 24174903 PMCID: PMC3811103 DOI: 10.31887/dcns.2013.15.3/ekim] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Molecular imaging techniques have a number of advantages for research into the pathophysiology and treatment of central nervous system (CNS) disorders. Firstly, they provide a noninvasive means of characterizing physiological processes in the living brain, enabling molecular alterations to be linked to clinical changes. Secondly, the pathophysiological target in a given CNS disorder can be measured in animal models and in experimental human models in the same way, which enables translational research. Moreover, as molecular imaging facilitates the detection of functional change which precedes gross pathology, it is particularly useful for the early diagnosis and treatment of CNS disorders. This review considers the application of molecular imaging to CNS disorders focusing on its potential to inform the development and evaluation of treatments. We focus on schizophrenia, Parkinson's disease, depression, and dementia as major CNS disorders. We also review the potential of molecular imaging to guide new drug development for CNS disorders.
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Affiliation(s)
- Euitae Kim
- Department of Neuropsychiatry, Seoul National University Bundang Hospital, Gyeonggi-do 463-707, Korea
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16
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Andrés JI, Alcázar J, Cid JM, De Angelis M, Iturrino L, Langlois X, Lavreysen H, Trabanco AA, Celen S, Bormans G. Synthesis, evaluation, and radiolabeling of new potent positive allosteric modulators of the metabotropic glutamate receptor 2 as potential tracers for positron emission tomography imaging. J Med Chem 2012; 55:8685-99. [PMID: 22992024 DOI: 10.1021/jm300912k] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The synthesis and in vitro and in vivo evaluation of a new series of 7-(phenylpiperidinyl)-1,2,4-triazolo[4,3-a]pyridines, which were conveniently radiolabeled with carbon-11, as potential positron emission tomography (PET) radiotracers for in vivo imaging of the allosteric binding site of the metabotropic glutamate (mGlu) receptor subtype 2 are described. The synthesized compounds proved to be potent and selective positive allosteric modulators (PAMs) of the mGlu receptor 2 (mGluR2) in a [³⁵S]GTPγS binding assay and were able to displace an mGluR2 PAM radioligand, which we had previously developed, with IC₅₀ values in the low nanomolar range. The most promising candidates were radiolabeled and subjected to biodistribution studies and radiometabolite analysis in rats. Preliminary small-animal PET (μPET) studies in rats indicated that [¹¹C]20f binds specifically and reversibly to an mGluR2 allosteric site, strongly suggesting that it is a promising candidate for PET imaging of mGluR2 in the brain.
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Affiliation(s)
- José-Ignacio Andrés
- Medicinal Chemistry, Janssen Research & Development , Janssen-Cilag S.A., C/Jarama 75, 45007 Toledo, Spain.
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