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Asch RH, Worhunsky PD, Davis MT, Holmes SE, Cool R, Boster S, Carson RE, Blumberg HP, Esterlis I. Deficits in prefrontal metabotropic glutamate receptor 5 are associated with functional alterations during emotional processing in bipolar disorder. J Affect Disord 2024; 361:415-424. [PMID: 38876317 PMCID: PMC11250898 DOI: 10.1016/j.jad.2024.06.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 05/23/2024] [Accepted: 06/10/2024] [Indexed: 06/16/2024]
Abstract
BACKGROUND Elucidating biological mechanisms contributing to bipolar disorder (BD) is key to improved diagnosis and treatment development. With converging evidence implicating the metabotropic glutamate receptor 5 (mGlu5) in the pathology of BD, here, we therefore test the hypothesis that recently identified deficits in mGlu5 are associated with functional brain differences during emotion processing in BD. METHODS Positron emission tomography (PET) with [18F]FPEB was used to measure mGlu5 receptor availability and functional imaging (fMRI) was performed while participants completed an emotion processing task. Data were analyzed from 62 individuals (33 ± 12 years, 45 % female) who completed both PET and fMRI, including individuals with BD (n = 18), major depressive disorder (MDD: n = 20), and psychiatrically healthy comparisons (HC: n = 25). RESULTS Consistent with some prior reports, the BD group displayed greater activation during fear processing relative to MDD and HC, notably in right lateralized frontal and parietal brain regions. In BD, (but not MDD or HC) lower prefrontal mGlu5 availability was associated with greater activation in bilateral pre/postcentral gyri and cuneus during fear processing. Furthermore, greater prefrontal mGlu5-related brain activity in BD was associated with difficulties in psychomotor function (r≥0.904, p≤0.005) and attention (r≥0.809, p≤0.028). LIMITATIONS The modest sample size is the primary limitation. CONCLUSIONS Deficits in prefrontal mGlu5 in BD were linked to increased cortical activation during fear processing, which in turn was associated with impulsivity and attentional difficulties. These data further implicate an mGlu5-related mechanism unique to BD. More generally these data suggest integrating PET and fMRI can provide novel mechanistic insights.
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Affiliation(s)
- Ruth H. Asch
- Department of Psychiatry, Yale School of Medicine, New Haven, CT 06511
| | | | - Margaret T. Davis
- Department of Psychiatry, Yale School of Medicine, New Haven, CT 06511
| | - Sophie E. Holmes
- Department of Psychiatry, Yale School of Medicine, New Haven, CT 06511
- Department of Neurology, Yale School of Medicine, New Haven, CT 06511
| | - Ryan Cool
- Department of Psychiatry, Yale School of Medicine, New Haven, CT 06511
| | - Sarah Boster
- Department of Psychiatry, Yale School of Medicine, New Haven, CT 06511
| | - Richard E. Carson
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT 06511
- Department of Biomedical Engineering, Yale School of Engineering and Applied Science, New Haven, CT 06511
| | - Hilary P. Blumberg
- Department of Psychiatry, Yale School of Medicine, New Haven, CT 06511
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT 06511
- Child Study Center, Yale School of Medicine, New Haven, CT 06511
| | - Irina Esterlis
- Department of Psychiatry, Yale School of Medicine, New Haven, CT 06511
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT 06511
- Department of Psychology, Yale University, New Haven, CT 06511
- U.S. Department of Veteran Affairs National Center for Posttraumatic Stress Disorder, Clinical Neurosciences Division, VA Connecticut Healthcare System, West Haven, CT 06516
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Jahan M, Amir A, Das A, Kihlström J, Nag S. Automated radiosynthesis of mGluR5 PET tracer [ 18F]FPEB from aryl-chloro precursor and validation for clinical application. J Labelled Comp Radiopharm 2024; 67:155-164. [PMID: 38369901 DOI: 10.1002/jlcr.4088] [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] [Received: 10/09/2023] [Revised: 12/11/2023] [Accepted: 01/29/2024] [Indexed: 02/20/2024]
Abstract
The radioligand [18F]FPEB, used for PET imaging of the brain's metabotropic glutamate receptor subtype 5 (mGluR5), undergoes a thorough validation process to ensure its safety, efficacy, and quality for clinical use. The process starts by optimizing the synthesis of [18F]FPEB to achieve high radiochemical yield and purity. This study focuses on optimizing the radiolabeling process using an aryl-chloro precursor and validating the GMP production for clinical applications. Fully automated radiolabeling was achieved via one-step nucleophilic substitution reaction. [18F]FPEB was produced and isolated in high radioactivity and radiochemical purity. Throughout the validation process, thorough quality control measures are implemented. Radiopharmaceutical batch release criteria are established, including testing for physical appearance, filter integrity, pH, radiochemical purity, molar activity, radiochemical identity, chemical impurity, structural identity, stability, residual solvent, sterility, and endotoxin levels. In conclusion, the validation of [18F]FPEB involved a comprehensive process of synthesis optimization, quality control, which ensure the safety, efficacy, and quality of [18F]FPEB, enabling its reliable use in clinical PET. Here, we successfully radiolabeled and validated [18F]FPEB using aryl-chloro precursor according to GMP production for clinical application.
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Affiliation(s)
- Mahabuba Jahan
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Arsalan Amir
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Arindam Das
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Jacob Kihlström
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Sangram Nag
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
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Fan S, Asch RH, Davis MT, DellaGioia N, Cool R, Blumberg HP, Esterlis I. Preliminary Study of White Matter Abnormalities and Associations With the Metabotropic Glutamate Receptor 5 to Distinguish Bipolar and Major Depressive Disorders. CHRONIC STRESS (THOUSAND OAKS, CALIF.) 2024; 8:24705470231225320. [PMID: 38250007 PMCID: PMC10798116 DOI: 10.1177/24705470231225320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 12/21/2023] [Indexed: 01/23/2024]
Abstract
Background Understanding distinct neurobiological mechanisms underlying bipolar disorder (BD) and major depressive disorder (MDD) is crucial for accurate diagnosis and the discovery of novel and more effective targeted treatments. Previous diffusion-weighted MRI studies have suggested some common frontotemporal corticolimbic system white matter (WM) abnormalities across the disorders. However, critical to the development of more precise diagnosis and treatment is identifying distinguishing abnormalities. Promising candidates include more prominent frontotemporal WM abnormalities observed in BD in the uncinate fasciculus (UF) that have been associated with frontal-amygdala functional dysconnectivity, and with suicide that is especially high in BD. Prior work also showed differentiation in metabotropic glutamate receptor 5 (mGlu5) abnormalities in BD versus MDD, which could be a mechanism affected in the frontotemporal system. However, associations between WM and mGlu5 have not been examined previously as a differentiator of BD. Using a multimodal neuroimaging approach, we examined WM integrity alterations in the disorders and their associations with mGluR5 levels. Methods Individuals with BD (N = 21), MDD (N = 10), and HC (N = 25) participated in structural and diffusion-weighted MRI scanning, and imaging with [18F]FPEB PET for quantification of mGlu5 availability. Whole-brain analyses were used to assess corticolimbic WM matter fractional anisotropy (FA) across BD and MDD relative to HC; abnormalities were tested for associations with mGlu5 availability. Results FA corticolimbic reductions were observed in both disorders and altered UF WM integrity was observed only in BD. In BD, lower UF FA was associated with lower amygdala mGlu5 availability (p < .05). Conclusions These novel preliminary findings suggest important associations between lower UF FA and lower amygdala mGlu5 levels that could represent a disorder-specific neural mechanism in which mGluR5 is associated with the frontotemporal dysconnectivity of the disorder.
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Affiliation(s)
- Siyan Fan
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
| | - Ruth H. Asch
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
| | - Margaret T. Davis
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
- Department of Psychology, Yale School of Medicine, New Haven, CT, USA
| | - Nicole DellaGioia
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
| | - Ryan Cool
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
| | - Hilary P. Blumberg
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
- Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT, USA
- Child Study Center, Yale School of Medicine, New Haven, CT, USA
| | - Irina Esterlis
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
- Department of Psychology, Yale School of Medicine, New Haven, CT, USA
- Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT, USA
- Clinical Neurosciences Division, U.S. Department of Veteran Affairs Nation Center for Posttraumatic Stress Disorder, VA Connecticut Healthcare System, West Haven, CT, USA
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Dupont AC, Arlicot N, Vercouillie J, Serrière S, Maia S, Bonnet-Brilhault F, Santiago-Ribeiro MJ. Metabotropic Glutamate Receptor Subtype 5 Positron-Emission-Tomography Radioligands as a Tool for Central Nervous System Drug Development: Between Progress and Setbacks. Pharmaceuticals (Basel) 2023; 16:1127. [PMID: 37631042 PMCID: PMC10458693 DOI: 10.3390/ph16081127] [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: 07/04/2023] [Revised: 08/03/2023] [Accepted: 08/09/2023] [Indexed: 08/27/2023] Open
Abstract
The metabotropic glutamate receptor subtype 5 (mGluR5) is a class C G-protein-coupled receptor (GPCR) that has been implicated in various neuronal processes and, consequently, in several neuropsychiatric or neurodevelopmental disorders. Over the past few decades, mGluR5 has become a major focus for pharmaceutical companies, as an attractive target for drug development, particularly through the therapeutic potential of its modulators. In particular, allosteric binding sites have been targeted for better specificity and efficacy. In this context, Positron Emission Tomography (PET) appears as a useful tool for making decisions along a drug candidate's development process, saving time and money. Thus, PET provides quantitative information about a potential drug candidate and its target at the molecular level. However, in this area, particular attention has to be given to the interpretation of the PET signal and its conclusions. Indeed, the complex pharmacology of both mGluR5 and radioligands, allosterism, the influence of endogenous glutamate and the choice of pharmacokinetic model are all factors that may influence the PET signal. This review focuses on mGluR5 PET radioligands used at several stages of central nervous system drug development, highlighting advances and setbacks related to the complex pharmacology of these radiotracers.
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Affiliation(s)
- Anne-Claire Dupont
- Radiopharmacie, CHRU de Tours, 37000 Tours, France
- UMR 1253, iBrain, Tours University, INSERM, 37000 Tours, France
| | - Nicolas Arlicot
- Radiopharmacie, CHRU de Tours, 37000 Tours, France
- UMR 1253, iBrain, Tours University, INSERM, 37000 Tours, France
- CIC 1415, Tours University, INSERM, 37000 Tours, France
| | | | - Sophie Serrière
- UMR 1253, iBrain, Tours University, INSERM, 37000 Tours, France
| | - Serge Maia
- Radiopharmacie, CHRU de Tours, 37000 Tours, France
- UMR 1253, iBrain, Tours University, INSERM, 37000 Tours, France
| | - Frédérique Bonnet-Brilhault
- UMR 1253, iBrain, Tours University, INSERM, 37000 Tours, France
- Excellence Center for Autism and Neurodevelopmental Disorders, CHRU de Tours, 37000 Tours, France
| | - Maria-Joao Santiago-Ribeiro
- UMR 1253, iBrain, Tours University, INSERM, 37000 Tours, France
- Nuclear Medicine Department, CHRU de Tours, 37000 Tours, France
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Holmes SE, Asch RH, Davis MT, DellaGioia N, Pashankar N, Gallezot JD, Nabulsi N, Matuskey D, Sanacora G, Carson RE, Blumberg HP, Esterlis I. Differences in Quantification of the Metabotropic Glutamate Receptor 5 Across Bipolar Disorder and Major Depressive Disorder. Biol Psychiatry 2023; 93:1099-1107. [PMID: 36764853 PMCID: PMC10164841 DOI: 10.1016/j.biopsych.2022.10.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 10/06/2022] [Accepted: 10/30/2022] [Indexed: 11/09/2022]
Abstract
BACKGROUND Understanding the neurobiology underlying bipolar disorder (BD) versus major depressive disorder (MDD) is crucial for accurate diagnosis and for driving the discovery of novel treatments. A promising target is the metabotropic glutamate receptor 5 (mGluR5), a modulator of glutamate transmission associated with synaptic plasticity. We measured mGluR5 availability in individuals with MDD and BD for the first time using positron emission tomography. METHODS Individuals with BD (n = 17 depressed; n = 10 euthymic) or MDD (n = 17) and healthy control (HC) individuals (n = 18) underwent imaging with [18F]FPEB positron emission tomography to quantify mGluR5 availability in regions of the prefrontal cortex, which was compared across groups and assessed in relation to depressive symptoms and cognitive function. RESULTS Prefrontal cortex mGluR5 availability was significantly different across groups (F6,116 = 2.18, p = .050). Specifically, mGluR5 was lower in BD versus MDD and HC groups, with no difference between MDD and HC groups. Furthermore, after dividing the BD group, mGluR5 was lower in both BD-depression and BD-euthymia groups versus both MDD and HC groups across regions of interest. Interestingly, lower dorsolateral prefrontal cortex mGluR5 was associated with worse depression in MDD (r = -0.67, p = .005) but not in BD. Significant negative correlations were observed between mGluR5 and working memory in MDD and BD-depression groups. CONCLUSIONS This work suggests that mGluR5 could be helpful in distinguishing BD and MDD as a possible treatment target for depressive symptoms in MDD and for cognitive alterations in both disorders. Further work is needed to confirm differentiating roles for mGluR5 in BD and MDD and to probe modulation of mGluR5 as a preventive/treatment strategy.
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Affiliation(s)
- Sophie E Holmes
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut
| | - Ruth H Asch
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut
| | - Margaret T Davis
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut; Department of Psychology, Yale University, New Haven, Connecticut
| | - Nicole DellaGioia
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut
| | - Neha Pashankar
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut
| | - Jean-Dominique Gallezot
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut
| | - Nabeel Nabulsi
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut
| | - David Matuskey
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut
| | - Gerard Sanacora
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut
| | - Richard E Carson
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut
| | - Hilary P Blumberg
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut; Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut; Child Study Center, Yale School of Medicine, New Haven, Connecticut
| | - Irina Esterlis
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut; Child Study Center, Yale School of Medicine, New Haven, Connecticut; Clinical Neurosciences Division, U.S. Department of Veteran Affairs National Center for Posttraumatic Stress Disorder, VA Connecticut Healthcare System, West Haven, Connecticut.
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Lopresti BJ, Royse SK, Mathis CA, Tollefson SA, Narendran R. Beyond monoamines: I. Novel targets and radiotracers for Positron emission tomography imaging in psychiatric disorders. J Neurochem 2023; 164:364-400. [PMID: 35536762 DOI: 10.1111/jnc.15615] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 04/05/2022] [Accepted: 04/06/2022] [Indexed: 10/18/2022]
Abstract
With the emergence of positron emission tomography (PET) in the late 1970s, psychiatry had access to a tool capable of non-invasive assessment of human brain function. Early applications in psychiatry focused on identifying characteristic brain blood flow and metabolic derangements using radiotracers such as [15 O]H2 O and [18 F]FDG. Despite the success of these techniques, it became apparent that more specific probes were needed to understand the neurochemical bases of psychiatric disorders. The first neurochemical PET imaging probes targeted sites of action of neuroleptic (dopamine D2 receptors) and psychoactive (serotonin receptors) drugs. Based on the centrality of monoamine dysfunction in psychiatric disorders and the measured success of monoamine-enhancing drugs in treating them, the next 30 years witnessed the development of an armamentarium of PET radiopharmaceuticals and imaging methodologies for studying monoamines. Continued development of monoamine-enhancing drugs over this time however was less successful, realizing only modest gains in efficacy and tolerability. As patent protection for many widely prescribed and profitable psychiatric drugs lapsed, drug development pipelines shifted away from monoamines in search of novel targets with the promises of improved efficacy, or abandoned altogether. Over this period, PET radiopharmaceutical development activities closely paralleled drug development priorities resulting in the development of new PET imaging agents for non-monoamine targets. Part one of this review will briefly survey novel PET imaging targets with relevance to the field of psychiatry, which include the metabotropic glutamate receptor type 5 (mGluR5), purinergic P2 X7 receptor, type 1 cannabinoid receptor (CB1 ), phosphodiesterase 10A (PDE10A), and describe radiotracers developed for these and other targets that have matured to human subject investigations. Current limitations of the targets and techniques will also be discussed.
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Affiliation(s)
- Brian J Lopresti
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Sarah K Royse
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Chester A Mathis
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Savannah A Tollefson
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Rajesh Narendran
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.,Departments of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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Laferriere-Holloway TS, Rios A, Lu Y, Okoro CC, van Dam RM. A rapid and systematic approach for the optimization of radio thin-layer chromatography resolution. J Chromatogr A 2023; 1687:463656. [PMID: 36463649 PMCID: PMC9894532 DOI: 10.1016/j.chroma.2022.463656] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 11/16/2022] [Accepted: 11/17/2022] [Indexed: 11/23/2022]
Abstract
Radiopharmaceutical analysis is limited by conventional methods. Radio-HPLC may be inaccurate for some compounds (e.g., 18F-radiopharmaceuticals) due to radionuclide sequester. Radio-TLC is simpler, faster, and detects all species but has limited resolution. Imaging-based readout of TLC plates (e.g., using Cerenkov luminescence imaging) can improve readout resolution, but the underlying chromatographic separation efficiency may be insufficient to resolve chemically similar species such as product and precursor-derived impurities. This study applies a systematic mobile phase optimization method, PRISMA, to improve radio-TLC resolution. The PRISMA method optimizes the mobile phase by selecting the correct solvent, optimizing solvent polarity, and optimizing composition. Without prior knowledge of impurities and by simply observing the separation resolution between a radiopharmaceutical and its nearest radioactive or non-radioactive impurities (observed via UV imaging) for different mobile phases, the PRISMA method enabled the development of high-resolution separation conditions for a wide range of 18F-radiopharmaceuticals ( [18F]PBR-06, [18F]FEPPA, [18F]Fallypride, [18F]FPEB, and [18F]FDOPA). Each optimization required a single batch of crude radiopharmaceutical and a few hours. Interestingly, the optimized TLC method provided greater accuracy (compared to other published TLC methods) in determining the product abundance of one radiopharmaceutical studied in more depth ( [18F]Fallypride) and was capable of resolving a comparable number of species as isocratic radio-HPLC. We used the PRISMA-optimized mobile phase for [18F]FPEB in combination with multi-lane radio-TLC techniques to evaluate reaction performance during high-throughput synthesis optimization of [18F]FPEB. The PRISMA methodology, in combination with high-resolution radio-TLC readout, enables a rapid and systematic approach to achieving high-resolution and accurate analysis of radiopharmaceuticals without the need for radio-HPLC.
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Affiliation(s)
- Travis S Laferriere-Holloway
- Department of Molecular & Medical Pharmacology, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, CA, USA; Crump Institute for Molecular Imaging, UCLA, Los Angeles, CA, USA.
| | - Alejandra Rios
- Physics and Biology in Medicine Interdepartmental Graduate Program, UCLA, Los Angeles, CA, USA; Crump Institute for Molecular Imaging, UCLA, Los Angeles, CA, USA
| | - Yingqing Lu
- Physics and Biology in Medicine Interdepartmental Graduate Program, UCLA, Los Angeles, CA, USA; Crump Institute for Molecular Imaging, UCLA, Los Angeles, CA, USA
| | - Chelsea C Okoro
- Institute for Society and Genetics, UCLA, Los Angeles, CA, USA; Crump Institute for Molecular Imaging, UCLA, Los Angeles, CA, USA
| | - R Michael van Dam
- Department of Molecular & Medical Pharmacology, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, CA, USA; Physics and Biology in Medicine Interdepartmental Graduate Program, UCLA, Los Angeles, CA, USA; Crump Institute for Molecular Imaging, UCLA, Los Angeles, CA, USA.
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8
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Baldassarri SR, Asch RH, Hillmer AT, Pietrzak RH, DellaGioia N, Esterlis I, Davis MT. Nicotine Use and Metabotropic Glutamate Receptor 5 in Individuals With Major Depressive and Posttraumatic Stress Disorders. CHRONIC STRESS (THOUSAND OAKS, CALIF.) 2023; 7:24705470231154842. [PMID: 36843572 PMCID: PMC9943964 DOI: 10.1177/24705470231154842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 01/18/2023] [Indexed: 02/12/2023]
Abstract
Metabotropic glutamate receptor 5 (mGluR5) dysregulation has been implicated in the pathophysiology of many psychiatric disorders, as well as nicotine use and dependence. We used positron emission tomography with [18F]FPEB to measure mGluR5 availability in vivo in 6 groups: (1) nicotine users (NUs) without other psychiatric comorbidities (n = 23); (2) comparison controls (CCs) without nicotine use or psychiatric comorbidities (n = 38); (3) major depressive disorder subjects with concurrent nicotine use (MDD-NU; n = 19); (4) MDD subjects without concurrent nicotine use (MDD-CC; n = 20); (5) posttraumatic stress disorder subjects with concurrent nicotine use (PTSD-NU; n = 17); and (6) PTSD subjects without concurrent nicotine use (PTSD-CC; n = 16). The goal of the study was to test the hypothesis that mGluR5 availability in key corticolimbic regions of interest (ROIs) is different in NU with versus without comorbid psychiatric disorders (ROI: dorsolateral prefrontal cortex [dlPFC], orbitofrontal cortex [OFC], ventromedial prefrontal cortex [vmPFC], anterior cingulate cortex [ACC], amygdala, hippocampus). We found that NU had 11%-13% lower mGluR5 availability in OFC, vmPFC, dlPFC, and ACC as compared with CC, while PTSD-NU had 9%-11% higher mGluR5 availability in OFC, dlPFC, and ACC compared with PTSD. Furthermore, relationships between mGluR5 availability and psychiatric symptoms varied as a function of psychiatric diagnosis among NUs. NU showed a negative correlation between mGluR5 and smoking cravings and urges (r's = -0.58 to -0.70, p's = 0.011 - 0.047), while PTSD-NU had the reverse relationship (r's = 0.60-0.71, p's = 0.013-0.035 in ACC, vmPFC, and dlPFC). These findings have substantial implications for our understanding of glutamate homeostasis in psychiatric subgroups and for identifying key neural phenotypes among NU. mGluR5 is a potential treatment target for precision medicine in individuals with nicotine use.
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Affiliation(s)
- Stephen R. Baldassarri
- Section of Pulmonary, Critical Care, & Sleep Medicine,
Department of Internal Medicine, Yale University School of
Medicine, New Haven, CT, USA
- Program in Addiction Medicine, Yale University School of
Medicine, New Haven, CT, USA
| | - Ruth H. Asch
- Departments of Psychiatry, Yale University School of
Medicine, New Haven, CT, USA
| | - Ansel T. Hillmer
- Departments of Psychiatry, Yale University School of
Medicine, New Haven, CT, USA
- Department of Radiology and Biomedical Imaging, Radiology, and
Biomedical Imaging, New Haven, CT, USA
| | - Robert H. Pietrzak
- Departments of Psychiatry, Yale University School of
Medicine, New Haven, CT, USA
- VA National Center for PTSD Clinical Neurosciences Division, New
Haven, CT, USA
| | - Nicole DellaGioia
- Departments of Psychiatry, Yale University School of
Medicine, New Haven, CT, USA
| | - Irina Esterlis
- Departments of Psychiatry, Yale University School of
Medicine, New Haven, CT, USA
- VA National Center for PTSD Clinical Neurosciences Division, New
Haven, CT, USA
| | - Margaret T. Davis
- Departments of Psychiatry, Yale University School of
Medicine, New Haven, CT, USA
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From bench to bedside: The mGluR5 system in people with and without Autism Spectrum Disorder and animal model systems. Transl Psychiatry 2022; 12:395. [PMID: 36127322 PMCID: PMC9489881 DOI: 10.1038/s41398-022-02143-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 08/19/2022] [Accepted: 09/01/2022] [Indexed: 11/08/2022] Open
Abstract
The metabotropic glutamate receptor 5 (mGluR5) is a key regulator of excitatory (E) glutamate and inhibitory (I) γ-amino butyric acid (GABA) signalling in the brain. Despite the close functional ties between mGluR5 and E/I signalling, no-one has directly examined the relationship between mGluR5 and glutamate or GABA in vivo in the human brain of autistic individuals. We measured [18F] FPEB (18F-3-fluoro-5-[(pyridin-3-yl)ethynyl]benzonitrile) binding in 15 adults (6 with Autism Spectrum Disorder) using two regions of interest, the left dorsomedial prefrontal cortex and a region primarily composed of left striatum and thalamus. These two regions were mapped out using MEGA-PRESS voxels and then superimposed on reconstructed PET images. This allowed for direct comparison between mGluR5, GABA + and Glx. To better understand the molecular underpinnings of our results we used an autoradiography study of mGluR5 in three mouse models associated with ASD: Cntnap2 knockout, Shank3 knockout, and 16p11.2 deletion. Autistic individuals had significantly higher [18F] FPEB binding (t (13) = -2.86, p = 0.047) in the left striatum/thalamus region of interest as compared to controls. Within this region, there was a strong negative correlation between GABA + and mGluR5 density across the entire cohort (Pearson's correlation: r (14) = -0.763, p = 0.002). Cntnap2 KO mice had significantly higher mGlu5 receptor binding in the striatum (caudate-putamen) as compared to wild-type (WT) mice (n = 15, p = 0.03). There were no differences in mGluR5 binding for mice with the Shank3 knockout or 16p11.2 deletion. Given that Cntnap2 is associated with a specific striatal deficit of parvalbumin positive GABA interneurons and 'autistic' features, our findings suggest that an increase in mGluR5 in ASD may relate to GABAergic interneuron abnormalities.
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Smart K, Worhunsky PD, Scheinost D, Angarita GA, Esterlis I, Carson RE, Krystal JH, O'Malley SS, Cosgrove KP, Hillmer AT. Multimodal neuroimaging of metabotropic glutamate 5 receptors and functional connectivity in alcohol use disorder. Alcohol Clin Exp Res 2022; 46:770-782. [PMID: 35342968 PMCID: PMC9117461 DOI: 10.1111/acer.14816] [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: 11/17/2021] [Revised: 03/15/2022] [Accepted: 03/19/2022] [Indexed: 12/01/2022]
Abstract
BACKGROUND People recovering from alcohol use disorder (AUD) show altered resting brain connectivity. The metabotropic glutamate 5 (mGlu5) receptor is an important regulator of synaptic plasticity potentially linked with synchronized brain activity and a target of interest in treating AUD. The goal of this work was to assess potential relationships of brain connectivity at rest with mGlu5 receptor availability in people with AUD at two time points early in abstinence. METHODS Forty-eight image data sets were acquired with a multimodal neuroimaging battery that included resting-state functional magnetic resonance imaging (fMRI) and mGlu5 receptor positron emission tomography (PET) with the radiotracer [18 F]FPEB. Participants with AUD (n = 14) were scanned twice, at approximately 1 and 4 weeks after beginning supervised abstinence. [18 F]FPEB PET results were published previously. Primary comparisons of fMRI outcomes were performed between the AUD group and healthy controls (HCs; n = 23) and assessed changes over time within the AUD group. Relationships between resting-state connectivity measures and mGlu5 receptor availability were explored within groups. RESULTS Compared to HCs, global functional connectivity of the orbitofrontal cortex was higher in the AUD group at 4 weeks of abstinence (p = 0.003), while network-level functional connectivity within the default mode network (DMN) was lower (p < 0.04). Exploratory multimodal analyses showed that mGlu5 receptor availability was correlated with global connectivity across all brain regions (HCs, r = 0.41; AUD group at 1 week of abstinence, r = 0.50 and at 4 weeks, r = 0.46; all p < 0.0001). Furthermore, a component of cortical and striatal mGlu5 availability was correlated with connectivity between the DMN and salience networks in HCs (r = 0.60, p = 0.003) but not in the AUD group (p > 0.3). CONCLUSIONS These preliminary findings of altered global and network connectivity during the first month of abstinence from drinking may reflect the loss of efficient network function, while exploratory relationships with mGlu5 receptor availability suggest a potential glutamatergic relationship with network coherence.
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Affiliation(s)
- Kelly Smart
- Yale PET Center, Yale School of Medicine, New Haven, Connecticut, USA.,Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut, USA
| | - Patrick D Worhunsky
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut, USA
| | - Dustin Scheinost
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut, USA.,Department of Biomedical Engineering, Yale School of Engineering & Applied Science, New Haven, Connecticut, USA
| | - Gustavo A Angarita
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut, USA
| | - Irina Esterlis
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut, USA
| | - Richard E Carson
- Yale PET Center, Yale School of Medicine, New Haven, Connecticut, USA.,Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut, USA.,Department of Biomedical Engineering, Yale School of Engineering & Applied Science, New Haven, Connecticut, USA
| | - John H Krystal
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut, USA
| | | | - Kelly P Cosgrove
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut, USA.,Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut, USA
| | - Ansel T Hillmer
- Yale PET Center, Yale School of Medicine, New Haven, Connecticut, USA.,Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut, USA.,Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut, USA.,Department of Biomedical Engineering, Yale School of Engineering & Applied Science, New Haven, Connecticut, USA
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11
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Tan Z, Wei H, Song X, Mai W, Yan J, Ye W, Ling X, Hou L, Zhang S, Yan S, Xu H, Wang L. Positron Emission Tomography in the Neuroimaging of Autism Spectrum Disorder: A Review. Front Neurosci 2022; 16:806876. [PMID: 35495051 PMCID: PMC9043810 DOI: 10.3389/fnins.2022.806876] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 03/14/2022] [Indexed: 12/11/2022] Open
Abstract
Autism spectrum disorder (ASD) is a basket term for neurodevelopmental disorders characterized by marked impairments in social interactions, repetitive and stereotypical behaviors, and restricted interests and activities. Subtypes include (A) disorders with known genetic abnormalities including fragile X syndrome, Rett syndrome, and tuberous sclerosis and (B) idiopathic ASD, conditions with unknown etiologies. Positron emission tomography (PET) is a molecular imaging technology that can be utilized in vivo for dynamic and quantitative research, and is a valuable tool for exploring pathophysiological mechanisms, evaluating therapeutic efficacy, and accelerating drug development in ASD. Recently, several imaging studies on ASD have been published and physiological changes during ASD progression was disclosed by PET. This paper reviews the specific radioligands for PET imaging of critical biomarkers in ASD, and summarizes and discusses the similar and different discoveries in outcomes of previous studies. It is of great importance to identify general physiological changes in cerebral glucose metabolism, cerebral blood flow perfusion, abnormalities in neurotransmitter systems, and inflammation in the central nervous system in ASD, which may provide excellent points for further ASD research.
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Affiliation(s)
- Zhiqiang Tan
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Huiyi Wei
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Xiubao Song
- Department of Rehabilitation Medicine, The First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, China
| | - Wangxiang Mai
- Department of Rehabilitation Medicine, The First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, China
| | - Jiajian Yan
- Department of Rehabilitation Medicine, The First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, China
| | - Weijian Ye
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Xueying Ling
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - 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, China
| | - Shaojuan Zhang
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Sen Yan
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory, Jinan University, Guangzhou, China
| | - Hao Xu
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou, China
- *Correspondence: Hao Xu,
| | - 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, China
- Lu Wang,
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12
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Brašić JR, Goodman JA, Nandi A, Russell DS, Jennings D, Barret O, Martin SD, Slifer K, Sedlak T, Mathur AK, Seibyl JP, Berry-Kravis EM, Wong DF, Budimirovic DB. Fragile X Mental Retardation Protein and Cerebral Expression of Metabotropic Glutamate Receptor Subtype 5 in Men with Fragile X Syndrome: A Pilot Study. Brain Sci 2022; 12:314. [PMID: 35326270 PMCID: PMC8946825 DOI: 10.3390/brainsci12030314] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 01/26/2022] [Accepted: 02/09/2022] [Indexed: 02/04/2023] Open
Abstract
Multiple lines of evidence suggest that a deficiency of Fragile X Mental Retardation Protein (FMRP) mediates dysfunction of the metabotropic glutamate receptor subtype 5 (mGluR5) in the pathogenesis of fragile X syndrome (FXS), the most commonly known single-gene cause of inherited intellectual disability (ID) and autism spectrum disorder (ASD). Nevertheless, animal and human studies regarding the link between FMRP and mGluR5 expression provide inconsistent or conflicting findings about the nature of those relationships. Since multiple clinical trials of glutamatergic agents in humans with FXS did not demonstrate the amelioration of the behavioral phenotype observed in animal models of FXS, we sought measure if mGluR5 expression is increased in men with FXS to form the basis for improved clinical trials. Unexpectedly marked reductions in mGluR5 expression were observed in cortical and subcortical regions in men with FXS. Reduced mGluR5 expression throughout the living brains of men with FXS provides a clue to examine FMRP and mGluR5 expression in FXS. In order to develop the findings of our previous study and to strengthen the objective tools for future clinical trials of glutamatergic agents in FXS, we sought to assess the possible value of measuring both FMRP levels and mGluR5 expression in men with FXS. We aimed to show the value of measurement of FMRP levels and mGluR5 expression for the diagnosis and treatment of individuals with FXS and related conditions. We administered 3-[18F]fluoro-5-(2-pyridinylethynyl)benzonitrile ([18F]FPEB), a specific mGluR5 radioligand for quantitative measurements of the density and the distribution of mGluR5s, to six men with the full mutation (FM) of FXS and to one man with allele size mosaicism for FXS (FXS-M). Utilizing the seven cortical and subcortical regions affected in neurodegenerative disorders as indicator variables, adjusted linear regression of mGluR5 expression and FMRP showed that mGluR5 expression was significantly reduced in the occipital cortex and the thalamus relative to baseline (anterior cingulate cortex) if FMRP levels are held constant (F(7,47) = 6.84, p < 0.001).These findings indicate the usefulness of cerebral mGluR5 expression measured by PET with [18F]FPEB and FMRP values in men with FXS and related conditions for assessments in community facilities within a hundred-mile radius of a production center with a cyclotron. These initial results of this pilot study advance our previous study regarding the measurement of mGluR5 expression by combining both FMRP levels and mGluR5 expression as tools for meaningful clinical trials of glutamatergic agents for men with FXS. We confirm the feasibility of this protocol as a valuable tool to measure FMRP levels and mGluR5 expression in clinical trials of individuals with FXS and related conditions and to provide the foundations to apply precision medicine to tailor treatment plans to the specific needs of individuals with FXS and related conditions.
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Affiliation(s)
- James Robert Brašić
- Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (A.N.); (S.D.M.); (T.S.); (A.K.M.); (D.F.W.)
| | - Jack Alexander Goodman
- Frank H. Netter MD School of Medicine, Quinnipiac University, North Haven, CT 06473, USA;
| | - Ayon Nandi
- Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (A.N.); (S.D.M.); (T.S.); (A.K.M.); (D.F.W.)
| | - David S. Russell
- Institute for Neurodegenerative Disorders, New Haven, CT 06510, USA; (D.S.R.); (D.J.); (O.B.); (J.P.S.)
- Invicro, New Haven, CT 06510, USA
| | - Danna Jennings
- Institute for Neurodegenerative Disorders, New Haven, CT 06510, USA; (D.S.R.); (D.J.); (O.B.); (J.P.S.)
- Invicro, New Haven, CT 06510, USA
- Denali Therapeutics, Inc., South San Francisco, CA 94080, USA
| | - Olivier Barret
- Institute for Neurodegenerative Disorders, New Haven, CT 06510, USA; (D.S.R.); (D.J.); (O.B.); (J.P.S.)
- Invicro, New Haven, CT 06510, USA
- Laboratoire des Maladies Neurodégénératives, Molecular Imaging Research Center (MIRCen), Institut de Biologie François Jacob, Centre National de la Recherche Scientifique (CNRS), Commissariat à l’Énergie Atomique et aux Énergies Alternatives (CEA), Université Paris-Saclay, CEDEX, 92265 Fontenay-aux-Roses, France
| | - Samuel D. Martin
- Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (A.N.); (S.D.M.); (T.S.); (A.K.M.); (D.F.W.)
- Department of Neuroscience, Zanvyl Krieger School of Arts and Sciences, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Keith Slifer
- Department of Psychiatry and Behavioral Sciences-Child Psychiatry, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA;
- Department of Behavioral Psychology, Kennedy Krieger Institute, Baltimore, MD 21205, USA
| | - Thomas Sedlak
- Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (A.N.); (S.D.M.); (T.S.); (A.K.M.); (D.F.W.)
- Department of Psychiatry and Behavioral Sciences-General Psychiatry, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Anil Kumar Mathur
- Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (A.N.); (S.D.M.); (T.S.); (A.K.M.); (D.F.W.)
| | - John P. Seibyl
- Institute for Neurodegenerative Disorders, New Haven, CT 06510, USA; (D.S.R.); (D.J.); (O.B.); (J.P.S.)
- Invicro, New Haven, CT 06510, USA
| | - Elizabeth M. Berry-Kravis
- Departments of Pediatrics, Neurological Sciences, and Biochemistry, Rush University Medical Center, Chicago, IL 60612, USA;
| | - Dean F. Wong
- Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (A.N.); (S.D.M.); (T.S.); (A.K.M.); (D.F.W.)
- Laboratory of Central Nervous System (CNS) Neuropsychopharmacology and Multimodal, Imaging (CNAMI), Mallinckrodt Institute of Radiology, Washington University, Saint Louis, MO 63110, USA
| | - Dejan B. Budimirovic
- Department of Psychiatry and Behavioral Sciences-Child Psychiatry, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA;
- Department of Psychiatry, Kennedy Krieger Institute, Baltimore, MD 21205, USA
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13
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Esterlis I, DeBonee S, Cool R, Holmes S, Baldassari SR, Maruff P, Pietrzak RH, Davis MT. Differential Role of mGluR5 in Cognitive Processes in Posttraumatic Stress Disorder and Major Depression. CHRONIC STRESS (THOUSAND OAKS, CALIF.) 2022; 6:24705470221105804. [PMID: 35958037 PMCID: PMC9358555 DOI: 10.1177/24705470221105804] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 05/23/2022] [Indexed: 11/16/2022]
Abstract
Background A robust literature supports the role of the metabotropic glutamate receptor type 5 (mGluR5) in cognitive functioning. mGluR5 is also implicated in the pathophysiology of posttraumatic stress disorder (PTSD) and major depressive disorder (MDD), which are characterized by cognitive alterations. However, the relationship between mGluR5 and cognition in MDD and PTSD has not yet been directly investigated. To address this gap, we examined the relationship between in vivo mGluR5 availability and cognition in PTSD, MDD, and matched healthy adults (HA). Methods Individuals with PTSD (N = 28) and MDD (N = 21), and HA (N = 28) were matched for age, gender, and smoking status. Participants completed 18F-FPEB positron emission tomography (PET) scan, psychiatric and cognitive assessments. Results Across models examining the relationship between mGluR5 availability and different domains of cognition across diagnostic groups, only the interaction of diagnosis*attention was significant (F 4,64 = 3.011, P = .024). Higher mGluR5 availability was associated with poorer attention in PTSD in 4 frontolimbic regions of interests (ROI's: OFC (r = -.441, P = .016), vmPFC (r = -.408, P = .028), dlPFC (r = -.421, P = .023), hippocampus (r = -.422, P = .025). By contrast, mGluR5 availability in the MDD group was positively related to Attention (ATTN) in the OFC (r = .590, P = .006), vmPFC (r = .653, P = .002), and dlPFC (r = .620, P = .004). Findings in the hippocampus for MDD followed the same pattern but did not survive correction for multiple comparisons (r = .480, P = .036). ATTN and mGluR5 availability were not significantly related in the HA group. Of note, in MANOVA analyses group*ATTN interaction results in the OFC did not survive multiple comparisons (P = .046). All other findings survived correction for multiple comparisons and remained significant when covarying for potential confounds (eg, depressed mood). Conclusions We observed a significant relationship between frontolimbic mGluR5 availability and performance on tests of attention in individuals with MDD and PTSD. This finding aligns with animal work showing dysregulation in mGluR5 in cognitive functioning, and differed as a function of diagnosis. Results suggest interventions targeting mGluR5 may help bolster cognitive difficulties, highlighting the importance of employing different mGluR5 directed treatment strategies in MDD and PTSD.
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Affiliation(s)
- Irina Esterlis
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- Department of Psychology, Yale University, New Haven, CT, USA
- National Center for Posttraumatic Stress Disorder, U.S. Department of Veterans Affairs, West Haven, CT, USA
| | - Sarah DeBonee
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Ryan Cool
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Sophie Holmes
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- Department of Psychology, Yale University, New Haven, CT, USA
- National Center for Posttraumatic Stress Disorder, U.S. Department of Veterans Affairs, West Haven, CT, USA
| | - Stephen R. Baldassari
- Department of Internal Medicine, Section of Pulmonary, Critical Care, and Sleep Medicine, Yale University School of Medicine, New Haven, CT, USA
- Program in Addiction Medicine, Yale University School of Medicine, New Haven, CT, USA
| | | | - Robert H. Pietrzak
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- National Center for Posttraumatic Stress Disorder, U.S. Department of Veterans Affairs, West Haven, CT, USA
| | - Margaret T. Davis
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- Department of Psychology, Yale University, New Haven, CT, USA
- National Center for Posttraumatic Stress Disorder, U.S. Department of Veterans Affairs, West Haven, CT, USA
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14
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NRM 2021 Abstract Booklet. J Cereb Blood Flow Metab 2021; 41:11-309. [PMID: 34905986 PMCID: PMC8851538 DOI: 10.1177/0271678x211061050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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15
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Babaei P. NMDA and AMPA receptors dysregulation in Alzheimer's disease. Eur J Pharmacol 2021; 908:174310. [PMID: 34265291 DOI: 10.1016/j.ejphar.2021.174310] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 07/02/2021] [Accepted: 07/05/2021] [Indexed: 11/17/2022]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative condition characterized by cognitive dysfunction and synaptic failure. The current therapeutic approaches are mainly focused on symptomatic treatment and possess limited effectiveness in addressing the pathophysiology of AD. It is known that neurodegeneration is negatively correlated with synaptic plasticity. This negative correlation highlights glutamatergic neurotransmission via N-methyl-D-aspartate (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors and (AMPA) receptors as a critical mediator of synaptic plasticity. Despite this favorable role, extensive extracellular glutamate concentration induces excitotoxicity and neurodegeneration. NMDA receptors containing GluN2A subunits are located at synaptic sites, implicated in the protective pathways. In comparison, GluN2B containing receptors are located mainly at extrasynaptic sites and increase neuronal vulnerability. AMPA receptors are consistently endocytosed and recycled back to the membrane. An increase in the rate of endocytosis has been implicated as a part of AD pathophysiology through inducing long-term depression (LTD) and synaptic disintegration. In the present review, we focused on the mechanisms of glutamatergic system dysregulation in AD, particularly on its interaction with amyloid-beta. We concluded that assigning a specific role to an individual subtype of either NMDA receptors or AMPA receptors might be an oversimplification as they are not static receptors. Therefore, any imbalance between synaptic and extrasynaptic NMDA receptors and a reduced number of surface AMPA receptors will lead to synaptopathy.
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Affiliation(s)
- Parvin Babaei
- Neuroscience Research Center, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran; Cellular &Molecular Research Center, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran; Department of Physiology, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
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16
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Mecca AP, Rogers K, Jacobs Z, McDonald JW, Michalak HR, DellaGioia N, Zhao W, Hillmer AT, Nabulsi N, Lim K, Ropchan J, Huang Y, Matuskey D, Esterlis I, Carson RE, van Dyck CH. Effect of age on brain metabotropic glutamate receptor subtype 5 measured with [ 18F]FPEB PET. Neuroimage 2021; 238:118217. [PMID: 34052464 PMCID: PMC8378132 DOI: 10.1016/j.neuroimage.2021.118217] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 04/08/2021] [Accepted: 05/26/2021] [Indexed: 12/31/2022] Open
Abstract
OBJECTIVE Metabotropic glutamate receptor subtype 5 (mGluR5) is integral to the brain glutamatergic system and cognitive function. This study investigated whether aging is associated with decreased brain mGluR5 availability. METHODS Cognitively normal participants (n = 45), aged 18 to 84 years, underwent [18F]FPEB positron emission tomography scans to quantify brain mGluR5. Distribution volume (VT) was computed using a venous or arterial input function and equilibrium modeling from 90 to 120 min. In the primary analysis, the association between age and VT in the hippocampus and association cortex was evaluated using a linear mixed model. Exploratory analyses assessed the association between age and VT in multiple brain regions. The contribution of gray matter tissue alterations and partial volume effects to associations with age was also examined. RESULTS In the primary analysis, older age was associated with lower [18F]FPEB binding to mGluR5 (P = 0.026), whereas this association was not significant after gray matter masking or partial volume correction to account for age-related tissue loss. Post hoc analyses revealed an age-related decline in mGluR5 availability in the hippocampus of 4.5% per decade (P = 0.007) and a non-significant trend in the association cortex (P = 0.085). An exploratory analysis of multiple brain regions revealed broader inverse associations of age with mGluR5 availability, but not after partial volume correction. CONCLUSION Reductions in mGluR5 availability with age appear to be largely mediated by tissue loss. Quantification of [18F]FPEB binding to mGluR5 may expand our understanding of age-related molecular changes and the relationship with brain tissue loss.
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Affiliation(s)
- Adam P Mecca
- Alzheimer's Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT, 06514, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA.
| | - Kelly Rogers
- Alzheimer's Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT, 06514, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Zachary Jacobs
- Alzheimer's Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT, 06514, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Julia W McDonald
- Alzheimer's Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT, 06514, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Hannah R Michalak
- Alzheimer's Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT, 06514, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Nicole DellaGioia
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Wenzhen Zhao
- Alzheimer's Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT, 06514, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Ansel T Hillmer
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA; Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Nabeel Nabulsi
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Keunpoong Lim
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Jim Ropchan
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Yiyun Huang
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - David Matuskey
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA; Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA; Department of Neurology, Yale University School of Medicine, New Haven, CT, USA
| | - Irina Esterlis
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Richard E Carson
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Christopher H van Dyck
- Alzheimer's Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT, 06514, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA; Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA; Department of Neurology, Yale University School of Medicine, New Haven, CT, USA
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17
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Mody M, Petibon Y, Han P, Kuruppu D, Ma C, Yokell D, Neelamegam R, Normandin MD, Fakhri GE, Brownell AL. In vivo imaging of mGlu5 receptor expression in humans with Fragile X Syndrome towards development of a potential biomarker. Sci Rep 2021; 11:15897. [PMID: 34354107 PMCID: PMC8342610 DOI: 10.1038/s41598-021-94967-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 07/16/2021] [Indexed: 11/21/2022] Open
Abstract
Fragile X Syndrome (FXS) is a neurodevelopmental disorder caused by silencing of the Fragile X Mental Retardation (FMR1) gene. The resulting loss of Fragile X Mental Retardation Protein (FMRP) leads to excessive glutamate signaling via metabotropic glutamate subtype 5 receptors (mGluR5) which has been implicated in the pathogenesis of the disorder. In the present study we used the radioligand 3-[18F]fluoro-5-(2-pyridinylethynyl)benzonitrile ([18F]FPEB) in simultaneous PET-MR imaging of males with FXS and age- and gender-matched controls to assess the availability of mGlu5 receptors in relevant brain areas. Patients with FXS showed lower [18F]FPEB binding potential (p < 0.01), reflecting reduced mGluR5 availability, than the healthy controls throughout the brain, with significant group differences in insula, anterior cingulate, parahippocampal, inferior temporal and olfactory cortices, regions associated with deficits in inhibition, memory, and visuospatial processes characteristic of the disorder. The results are among the first to provide in vivo evidence of decreased availability of mGluR5 in the brain in individuals with FXS than in healthy controls. The consistent results across the subjects, despite the tremendous challenges with neuroimaging this population, highlight the robustness of the protocol and support for its use in drug occupancy studies; extending our radiotracer development and application efforts from mice to humans.
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Affiliation(s)
- Maria Mody
- Athinoula A Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02129, USA.
| | - Yoann Petibon
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02129, USA
| | - Paul Han
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02129, USA
| | - Darshini Kuruppu
- Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02129, USA
| | - Chao Ma
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02129, USA
| | - Daniel Yokell
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02129, USA
| | - Ramesh Neelamegam
- Department of Radiology, University of Texas Health Science at San Antonio, San Antonio, TX, 78229, USA
| | - Marc D Normandin
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02129, USA
| | - Georges El Fakhri
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02129, USA
| | - Anna-Liisa Brownell
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, 02129, USA
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Brašić JR, Nandi A, Russell DS, Jennings D, Barret O, Martin SD, Slifer K, Sedlak T, Seibyl JP, Wong DF, Budimirovic DB. Cerebral Expression of Metabotropic Glutamate Receptor Subtype 5 in Idiopathic Autism Spectrum Disorder and Fragile X Syndrome: A Pilot Study. Int J Mol Sci 2021; 22:2863. [PMID: 33799851 PMCID: PMC7999711 DOI: 10.3390/ijms22062863] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 02/26/2021] [Accepted: 03/04/2021] [Indexed: 12/13/2022] Open
Abstract
Multiple lines of evidence suggest that dysfunction of the metabotropic glutamate receptor subtype 5 (mGluR5) plays a role in the pathogenesis of autism spectrum disorder (ASD). Yet animal and human investigations of mGluR5 expression provide conflicting findings about the nature of dysregulation of cerebral mGluR5 pathways in subtypes of ASD. The demonstration of reduced mGluR5 expression throughout the living brains of men with fragile X syndrome (FXS), the most common known single-gene cause of ASD, provides a clue to examine mGluR5 expression in ASD. We aimed to (A) compare and contrast mGluR5 expression in idiopathic autism spectrum disorder (IASD), FXS, and typical development (TD) and (B) show the value of positron emission tomography (PET) for the application of precision medicine for the diagnosis and treatment of individuals with IASD, FXS, and related conditions. Two teams of investigators independently administered 3-[18F]fluoro-5-(2-pyridinylethynyl)benzonitrile ([18F]FPEB), a novel, specific mGluR5 PET ligand to quantitatively measure the density and the distribution of mGluR5s in the brain regions, to participants of both sexes with IASD and TD and men with FXS. In contrast to participants with TD, mGluR5 expression was significantly increased in the cortical regions of participants with IASD and significantly reduced in all regions of men with FXS. These results suggest the feasibility of this protocol as a valuable tool to measure mGluR5 expression in clinical trials of individuals with IASD and FXS and related conditions.
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Affiliation(s)
- James Robert Brašić
- Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (A.N.); (S.D.M.); (T.S.); (D.F.W.)
| | - Ayon Nandi
- Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (A.N.); (S.D.M.); (T.S.); (D.F.W.)
| | - David S. Russell
- Institute for Neurodegenerative Disorders, New Haven, CT 06510, USA; (D.S.R.); (D.J.); (O.B.); (J.P.S.)
- Research Clinic, Invicro, New Haven, CT 06510, USA
| | - Danna Jennings
- Institute for Neurodegenerative Disorders, New Haven, CT 06510, USA; (D.S.R.); (D.J.); (O.B.); (J.P.S.)
- Research Clinic, Invicro, New Haven, CT 06510, USA
- Denali Therapeutics, Inc., South San Francisco, CA 94080, USA
| | - Olivier Barret
- Institute for Neurodegenerative Disorders, New Haven, CT 06510, USA; (D.S.R.); (D.J.); (O.B.); (J.P.S.)
- Research Clinic, Invicro, New Haven, CT 06510, USA
- Laboratoire des Maladies Neurodégénératives, Molecular Imaging Research Center (MIRCen), Institut de Biologie François Jacob, Centre National de la Recherche Scientifique (CNRS), Commissariat à l’Énergie Atomique et aux Énergies Alternatives (CEA), Université Paris-Saclay, 92265 Fontenay-aux-Roses CEDEX, France
| | - Samuel D. Martin
- Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (A.N.); (S.D.M.); (T.S.); (D.F.W.)
- Department of Neuroscience, Zanvyl Krieger School of Arts and Sciences, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Keith Slifer
- Department of Psychiatry and Behavioral Sciences-Child Psychiatry, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA;
- Department of Behavioral Psychology, Kennedy Krieger Institute, Baltimore, MD 21205, USA
| | - Thomas Sedlak
- Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (A.N.); (S.D.M.); (T.S.); (D.F.W.)
- Department of Psychiatry and Behavioral Sciences-General Psychiatry, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - John P. Seibyl
- Institute for Neurodegenerative Disorders, New Haven, CT 06510, USA; (D.S.R.); (D.J.); (O.B.); (J.P.S.)
- Research Clinic, Invicro, New Haven, CT 06510, USA
| | - Dean F. Wong
- Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (A.N.); (S.D.M.); (T.S.); (D.F.W.)
- Laboratory of Central Nervous System (CNS) Neuropsychopharmacology and Multimodal Imaging (CNAMI), Mallinckrodt Institute of Radiology, Washington University, Saint Louis, MO 63110, USA
| | - Dejan B. Budimirovic
- Department of Psychiatry and Behavioral Sciences-Child Psychiatry, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA;
- Department of Psychiatry, Kennedy Krieger Institute, Baltimore, MD 21205, USA
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Bennett KA, Sergeev E, MacSweeney CP, Bakker G, Cooper AE. Understanding Exposure-Receptor Occupancy Relationships for Metabotropic Glutamate Receptor 5 Negative Allosteric Modulators across a Range of Preclinical and Clinical Studies. J Pharmacol Exp Ther 2021; 377:157-168. [PMID: 33541889 DOI: 10.1124/jpet.120.000371] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 01/26/2021] [Indexed: 01/17/2023] Open
Abstract
The metabotropic glutamate receptor 5 (mGlu5) is a recognized central nervous system therapeutic target for which several negative allosteric modulator (NAM) drug candidates have or are continuing to be investigated for various disease indications in clinical development. Direct measurement of target receptor occupancy (RO) is extremely useful to help design and interpret efficacy and safety in nonclinical and clinical studies. In the mGlu5 field, this has been successfully achieved by monitoring displacement of radiolabeled ligands, specifically binding to the mGlu5 receptor, in the presence of an mGlu5 NAM using in vivo and ex vivo binding in rodents and positron emission tomography imaging in cynomolgus monkeys and humans. The aim of this study was to measure the RO of the mGlu5 NAM HTL0014242 in rodents and cynomolgus monkeys and to compare its plasma and brain exposure-RO relationships with those of clinically tested mGlu5 NAMs dipraglurant, mavoglurant, and basimglurant. Potential sources of variability that may contribute to these relationships were explored. Distinct plasma exposure-response relationships were found for each mGlu5 NAM, with >100-fold difference in plasma exposure for a given level of RO. However, a unified exposure-response relationship was observed when both unbound brain concentration and mGlu5 affinity were considered. This relationship showed <10-fold overall difference, was fitted with a Hill slope that was not significantly different from 1, and appeared consistent with a simple Emax model. This is the first time this type of comparison has been conducted, demonstrating a unified brain exposure-RO relationship across several species and mGlu5 NAMs with diverse properties. SIGNIFICANCE STATEMENT: Despite the long history of mGlu5 as a therapeutic target and progression of multiple compounds to the clinic, no formal comparison of exposure-receptor occupancy relationships has been conducted. The data from this study indicate for the first time that a consistent, unified relationship can be observed between exposure and mGlu5 receptor occupancy when unbound brain concentration and receptor affinity are taken into account across a range of species for a diverse set of mGlu5 negative allosteric modulators, including a new drug candidate, HTL0014242.
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Affiliation(s)
| | | | | | - Geor Bakker
- Sosei Heptares, Cambridge, CB21 6DG, United Kingdom
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20
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Longitudinal imaging of metabotropic glutamate 5 receptors during early and extended alcohol abstinence. Neuropsychopharmacology 2021; 46:380-385. [PMID: 32919411 PMCID: PMC7852514 DOI: 10.1038/s41386-020-00856-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 08/10/2020] [Accepted: 08/27/2020] [Indexed: 01/22/2023]
Abstract
Chronic alcohol use has important effects on the glutamate system. The metabotropic glutamate 5 (mGlu5) receptor has shown promise in preclinical models as a target to reduce drinking-related behaviors and cue-induced reinstatement, motivating human studies of mGlu5 receptor negative allosteric modulators. The goal of this work was to measure levels of mGlu5 receptor availability with positron emission tomography (PET) imaging using the mGlu5 receptor-specific radiotracer [18F]FPEB during early and extended alcohol abstinence. Subjects who met DSM-5 criteria for alcohol use disorder (AUD; n = 17) were admitted inpatient for the study duration. [18F]FPEB PET scans were acquired first during early abstinence (6 ± 4 days after last drink) and a second time during extended abstinence (n = 13; 27 ± 6 days after last drink). A single scan was acquired in healthy controls matched for sex and smoking status (n = 20). [18F]FPEB total volumes of distribution (VT) corrected for partial volume effects were measured using equilibrium analysis throughout the brain. A linear mixed model controlling for smoking status and sex identified significantly higher [18F]FPEB VT in AUD subjects at early abstinence compared to controls (F(1,32) = 7.23, p = 0.011). Post-hoc analyses revealed this effect to occur in cortical brain regions. No evidence for significant changes in [18F]FPEB VT over time were established. These findings provide human evidence consistent with a robust preclinical literature supporting mGlu5 receptor drugs as pharmacotherapies for AUD.
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21
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Brašić JR, Nandi A, Russell DS, Jennings D, Barret O, Mathur A, Slifer K, Sedlak T, Martin SD, Brinson Z, Vyas P, Seibyl JP, Berry-Kravis EM, Wong DF, Budimirovic DB. Reduced Expression of Cerebral Metabotropic Glutamate Receptor Subtype 5 in Men with Fragile X Syndrome. Brain Sci 2020; 10:E899. [PMID: 33255214 PMCID: PMC7760509 DOI: 10.3390/brainsci10120899] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 11/07/2020] [Accepted: 11/14/2020] [Indexed: 12/28/2022] Open
Abstract
Glutamatergic receptor expression is mostly unknown in adults with fragile X syndrome (FXS). Favorable behavioral effects of negative allosteric modulators (NAMs) of the metabotropic glutamate receptor subtype 5 (mGluR5) in fmr1 knockout (KO) mouse models have not been confirmed in humans with FXS. Measurement of cerebral mGluR5 expression in humans with FXS exposed to NAMs might help in that effort. We used positron emission tomography (PET) to measure the mGluR5 density as a proxy of mGluR5 expression in cortical and subcortical brain regions to confirm target engagement of NAMs for mGluR5s. The density and the distribution of mGluR5 were measured in two independent samples of men with FXS (N = 9) and typical development (TD) (N = 8). We showed the feasibility of this complex study including MRI and PET, meaning that this challenging protocol can be accomplished in men with FXS with an adequate preparation. Analysis of variance of estimated mGluR5 expression showed that mGluR5 expression was significantly reduced in cortical and subcortical regions of men with FXS in contrast to age-matched men with TD.
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Affiliation(s)
- James R. Brašić
- Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (A.N.); (A.M.); (T.S.); (S.D.M.); (Z.B.); (P.V.); (D.F.W.)
| | - Ayon Nandi
- Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (A.N.); (A.M.); (T.S.); (S.D.M.); (Z.B.); (P.V.); (D.F.W.)
| | - David S. Russell
- Clinical Research, Institute for Neurodegenerative Disorders, New Haven, CT 06510, USA; (D.S.R.); (D.J.); (O.B.); (J.P.S.)
- Research Clinic, Invicro LLC, New Haven, CT 06510, USA
| | - Danna Jennings
- Clinical Research, Institute for Neurodegenerative Disorders, New Haven, CT 06510, USA; (D.S.R.); (D.J.); (O.B.); (J.P.S.)
- Research Clinic, Invicro LLC, New Haven, CT 06510, USA
- Denali Therapeutics, Inc., South San Francisco, CA 94080, USA
| | - Olivier Barret
- Clinical Research, Institute for Neurodegenerative Disorders, New Haven, CT 06510, USA; (D.S.R.); (D.J.); (O.B.); (J.P.S.)
| | - Anil Mathur
- Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (A.N.); (A.M.); (T.S.); (S.D.M.); (Z.B.); (P.V.); (D.F.W.)
| | - Keith Slifer
- Department of Psychiatry and Behavioral Sciences-Child Psychiatry, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA;
- Department of Behavioral Psychology, Kennedy Krieger Institute, Baltimore, MD 21205, USA
| | - Thomas Sedlak
- Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (A.N.); (A.M.); (T.S.); (S.D.M.); (Z.B.); (P.V.); (D.F.W.)
- Department of Psychiatry and Behavioral Sciences-General Psychiatry, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Samuel D. Martin
- Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (A.N.); (A.M.); (T.S.); (S.D.M.); (Z.B.); (P.V.); (D.F.W.)
- Department of Neuroscience, Zanvyl Krieger School of Arts and Sciences, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Zabecca Brinson
- Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (A.N.); (A.M.); (T.S.); (S.D.M.); (Z.B.); (P.V.); (D.F.W.)
| | - Pankhuri Vyas
- Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (A.N.); (A.M.); (T.S.); (S.D.M.); (Z.B.); (P.V.); (D.F.W.)
| | - John P. Seibyl
- Clinical Research, Institute for Neurodegenerative Disorders, New Haven, CT 06510, USA; (D.S.R.); (D.J.); (O.B.); (J.P.S.)
- Research Clinic, Invicro LLC, New Haven, CT 06510, USA
| | - Elizabeth M. Berry-Kravis
- Departments of Pediatrics, Neurological Sciences, and Biochemistry, Rush University Medical Center, Chicago, IL 60612, USA;
| | - Dean F. Wong
- Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (A.N.); (A.M.); (T.S.); (S.D.M.); (Z.B.); (P.V.); (D.F.W.)
- Precision Radio-Theranostics Translational Laboratories, Mallinckrodt Institute of Radiology, School of Medicine, Washington University, Saint Louis, MO 63110, USA
| | - Dejan B. Budimirovic
- Department of Psychiatry and Behavioral Sciences-Child Psychiatry, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA;
- Departments of Psychiatry and Neurogenetics, Kennedy Krieger Institute, Baltimore, MD 21205, USA
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22
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Holmes SE, Gallezot JD, Davis MT, DellaGioia N, Matuskey D, Nabulsi N, Krystal JH, Javitch JA, DeLorenzo C, Carson RE, Esterlis I. Measuring the effects of ketamine on mGluR5 using [ 18F]FPEB and PET. J Cereb Blood Flow Metab 2020; 40:2254-2264. [PMID: 31744389 PMCID: PMC7585925 DOI: 10.1177/0271678x19886316] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 09/23/2019] [Accepted: 10/03/2019] [Indexed: 01/21/2023]
Abstract
The metabotropic glutamate receptor 5 (mGluR5) is a promising treatment target for psychiatric disorders due to its modulatory effects on glutamate transmission. Using [11C]ABP688, we previously showed that the rapidly acting antidepressant ketamine decreases mGluR5 availability. The mGluR5 radioligand [18F]FPEB offers key advantages over [11C]ABP688; however, its suitability for drug challenge studies is unknown. We evaluated whether [18F]FPEB can be used to capture ketamine-induced effects on mGluR5. Seven healthy subjects participated in three [18F]FPEB scans: a baseline, a same-day post-ketamine, and a 24-h post-ketamine scan. The outcome measure was VT/fP, obtained using a two-tissue compartment model and a metabolite-corrected arterial input function. Dissociative symptoms, heart rate and blood pressure increased following ketamine infusion. [18F]FPEB VT/fP decreased by 9% across the cortex after ketamine infusion, with minimal difference between baseline and 24-h scans. Compared to our previous work using [11C]ABP688, the magnitude of the ketamine-induced change in mGluR5 was smaller using [18F]FPEB; however, effect sizes were similar for the same-day post-ketamine vs. baseline scan (Cohen's d = 0.75 for [18F]FPEB and 0.88 for [11C]ABP688). [18F]FPEB is therefore able to capture some of the effects of ketamine on mGluR5, but [11C]ABP688 appears to be more suitable in drug challenge paradigms designed to probe glutamate transmission.
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Affiliation(s)
- Sophie E Holmes
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
| | | | - Margaret T Davis
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
| | - Nicole DellaGioia
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
| | - David Matuskey
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
- Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT, USA
| | - Nabeel Nabulsi
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
| | - John H Krystal
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
- U.S. Department of Veteran Affairs National Center for Posttraumatic Stress Disorder, Clinical Neurosciences Division, VA Connecticut Healthcare System, West Haven, CT, USA
| | - Jonathan A Javitch
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, USA
- Departments of Psychiatry and Pharmacology, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Christine DeLorenzo
- Department of Psychiatry and Behavioral Health, Stony Brook University, New York, NY, USA
| | - Richard E Carson
- Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT, USA
| | - Irina Esterlis
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, USA
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23
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Association between human gray matter metabotropic glutamate receptor-5 availability in vivo and white matter properties: a [ 11C]ABP688 PET and diffusion tensor imaging study. Brain Struct Funct 2020; 225:1805-1816. [PMID: 32495131 DOI: 10.1007/s00429-020-02094-7] [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: 12/23/2019] [Accepted: 05/26/2020] [Indexed: 10/24/2022]
Abstract
Excitatory corticofugal projections in the subcortical white matter (WM) convey signals arising from local neuronal activity in the gray matter (GM). We hypothesized that metabotropic glutamate receptor-5 (mGluR5) availability in GM, as a surrogate marker for local glutamatergic neuronal activity, correlates with WM properties in healthy brain. We examined the relationship in healthy individuals between GM mGluR5 availability measured in vivo using [11C]ABP688 positron emission tomography (PET) and WM properties measured as fractional anisotropy (FA) using diffusion tensor imaging (DTI). Twenty-three healthy volunteers underwent this multimodal imaging. We calculated mGluR5 availability, [11C]ABP688 binding potential (BPND), using the simplified reference tissue model, and generated DTI FA maps using FMRIB's Diffusion Toolbox (FDT) along with Tract-Based Spatial Statistics (TBSS). To investigate the relationship between mGluR5 availability and FA, we performed voxel-wise and region of interest (ROI)-based analyses. The voxel-wise analysis showed significant positive correlations between the whole cerebral GM [11C]ABP688 BPND and the FA in widespread WM regions including the corpus callosum body, internal capsule, and corona radiata (FWE corrected p < 0.05). The ROI-based analysis also revealed significant positive correlations (Bonferroni-corrected threshold p < 0.00021) between [11C]ABP688 BPND in the frontal and parietal cortical GM and FA in the internal capsule (anterior limb and retrolenticular part). Using a novel multimodal imaging interrogation, we provide the first evidence that GM mGluR5 availability is significantly positively associated with WM properties in healthy subjects. Future comparison studies could determine whether this relationship is perturbed in neuropsychiatric disorders with dysregulated mGluR5 signaling.
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Hillmer AT, Carson RE. Quantification of PET infusion studies without true equilibrium: A tissue clearance correction. J Cereb Blood Flow Metab 2020; 40:860-874. [PMID: 31088233 PMCID: PMC7168787 DOI: 10.1177/0271678x19850000] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 04/21/2019] [Indexed: 11/16/2022]
Abstract
In some positron emission tomography (PET) studies, a reversibly binding radioligand is administered as a constant infusion to establish true equilibrium for quantification. This approach reduces scanning time and simplifies data analysis, but assumes similar behavior of the radioligand in plasma across the study population to establish true equilibrium in all subjects. Bias in outcome measurements can result if this assumption is not met. This work developed and validated a correction that reduces bias in total distribution volume (VT) estimates when true equilibrium is not present. This correction, termed tissue clearance correction (TCC), took the form V T = V T ( A ) / ( 1 + β γ V T ( A ) ) , where β is the radioligand clearance rate in tissue, γ is a radiotracer-specific constant, and VT(A) is the apparent VT. Simulations characterized the robustness of TCC across imperfect values of γ and β and demonstrated reduction to false positive rates. This approach was validated with human infusion data for three radiotracers: [18F]FPEB, (-)-[18F]flubatine, and [11C]UCB-J. TCC reduced bias in VT estimates for all radiotracers and significantly reduced intersubject variance in VT for [18F]FPEB data in some brain regions. Thus, TCC improves quantification of data acquired from PET infusion studies.
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Affiliation(s)
- Ansel T Hillmer
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- Yale University PET Center, Yale University School of Medicine, New Haven, CT, USA
| | - Richard E Carson
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
- Yale University PET Center, Yale University School of Medicine, New Haven, CT, USA
- Department of Biomedical Engineering, Yale School of Engineering & Applied Science, New Haven, CT, USA
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Mota F, Sementa T, Taddei C, Moses N, Bordoloi J, Hader S, Eykyn T, Cash D, Turkheimer F, Veronese M, Singh N. Investigating the effects of ebselen, a potential new lithium mimetic, on glutamate transmission. Synapse 2020; 74:e22151. [PMID: 32056277 DOI: 10.1002/syn.22151] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 02/11/2020] [Accepted: 02/11/2020] [Indexed: 11/10/2022]
Abstract
Ebselen, a potential new lithium-like drug, treatment reduced brain glutamate, as measured by PET imaging using the mGluR5 radioligand [18 F]FPEB in rats.
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Affiliation(s)
- Filipa Mota
- School of Biomedical Engineering & Imaging Sciences, 4th floor Lambeth Wing, St Thomas' Hospital, King's College, London, UK
| | - Teresa Sementa
- School of Biomedical Engineering & Imaging Sciences, 4th floor Lambeth Wing, St Thomas' Hospital, King's College, London, UK
| | - Carlotta Taddei
- School of Biomedical Engineering & Imaging Sciences, 4th floor Lambeth Wing, St Thomas' Hospital, King's College, London, UK
| | - Natasha Moses
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College, London, UK
| | - Jayanta Bordoloi
- School of Biomedical Engineering & Imaging Sciences, 4th floor Lambeth Wing, St Thomas' Hospital, King's College, London, UK
| | - Stefan Hader
- School of Biomedical Engineering & Imaging Sciences, 4th floor Lambeth Wing, St Thomas' Hospital, King's College, London, UK
| | - Thomas Eykyn
- School of Biomedical Engineering & Imaging Sciences, 4th floor Lambeth Wing, St Thomas' Hospital, King's College, London, UK
| | - Diana Cash
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College, London, UK
| | - Federico Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College, London, UK
| | - Mattia Veronese
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College, London, UK
| | - Nisha Singh
- School of Biomedical Engineering & Imaging Sciences, 4th floor Lambeth Wing, St Thomas' Hospital, King's College, London, UK.,Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College, London, UK
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26
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Varlow C, Murrell E, Holland JP, Kassenbrock A, Shannon W, Liang SH, Vasdev N, Stephenson NA. Revisiting the Radiosynthesis of [ 18F]FPEB and Preliminary PET Imaging in a Mouse Model of Alzheimer's Disease. Molecules 2020; 25:molecules25040982. [PMID: 32098347 PMCID: PMC7070414 DOI: 10.3390/molecules25040982] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 02/19/2020] [Accepted: 02/20/2020] [Indexed: 11/24/2022] Open
Abstract
[18F]FPEB is a positron emission tomography (PET) radiopharmaceutical used for imaging the abundance and distribution of mGluR5 in the central nervous system (CNS). Efficient radiolabeling of the aromatic ring of [18F]FPEB has been an ongoing challenge. Herein, five metal-free precursors for the radiofluorination of [18F]FPEB were compared, namely, a chloro-, nitro-, sulfonium salt, and two spirocyclic iodonium ylide (SCIDY) precursors bearing a cyclopentyl (SPI5) and a new adamantyl (SPIAd) auxiliary. The chloro- and nitro-precursors resulted in a low radiochemical yield (<10% RCY), whereas both SCIDY precursors and the sulfonium salt precursor produced [18F]FPEB in the highest RCYs of 25% and 36%, respectively. Preliminary PET/CT imaging studies with [18F]FPEB were conducted in a transgenic model of Alzheimer’s Disease (AD) using B6C3-Tg(APPswe,PSEN1dE9)85Dbo/J (APP/PS1) mice, and data were compared with age-matched wild-type (WT) B6C3F1/J control mice. In APP/PS1 mice, whole brain distribution at 5 min post-injection showed a slightly higher uptake (SUV = 4.8 ± 0.4) than in age-matched controls (SUV = 4.0 ± 0.2). Further studies to explore mGluR5 as an early biomarker for AD are underway.
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Affiliation(s)
- Cassis Varlow
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON M5T 1R8, Canada; (C.V.); (E.M.); (W.S.)
- Institute of Medical Science, University of Toronto, Toronto, ON M5S1A8, Canada
| | - Emily Murrell
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON M5T 1R8, Canada; (C.V.); (E.M.); (W.S.)
| | - Jason P. Holland
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA 02114, USA; (J.P.H.); (A.K.); (S.H.L.)
- Department of Chemistry, University of Zurich, 8057 Zurich, Switzerland
| | - Alina Kassenbrock
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA 02114, USA; (J.P.H.); (A.K.); (S.H.L.)
| | - Whitney Shannon
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON M5T 1R8, Canada; (C.V.); (E.M.); (W.S.)
- Department of Chemistry, University of Saskatchewan, Saskatoon, SK S7N OX2, Canada
| | - Steven H. Liang
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA 02114, USA; (J.P.H.); (A.K.); (S.H.L.)
| | - Neil Vasdev
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON M5T 1R8, Canada; (C.V.); (E.M.); (W.S.)
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA 02114, USA; (J.P.H.); (A.K.); (S.H.L.)
- Department of Psychiatry, University of Toronto, Toronto, ON M5T-1R8, Canada
- Correspondence: (N.V.); (N.A.S.); Tel.: +416-535-8501 (ext. 30988) (N.V.); +1-876-927-1910 (N.A.S.)
| | - Nickeisha A. Stephenson
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON M5T 1R8, Canada; (C.V.); (E.M.); (W.S.)
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital & Department of Radiology, Harvard Medical School, Boston, MA 02114, USA; (J.P.H.); (A.K.); (S.H.L.)
- Department of Chemistry, The University of West Indies at Mona, Kingston 7, Jamaica
- Correspondence: (N.V.); (N.A.S.); Tel.: +416-535-8501 (ext. 30988) (N.V.); +1-876-927-1910 (N.A.S.)
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27
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Mecca AP, McDonald JW, Michalak HR, Godek TA, Harris JE, Pugh EA, Kemp EC, Chen MK, Salardini A, Nabulsi NB, Lim K, Huang Y, Carson RE, Strittmatter SM, van Dyck CH. PET imaging of mGluR5 in Alzheimer's disease. Alzheimers Res Ther 2020; 12:15. [PMID: 31954399 PMCID: PMC6969979 DOI: 10.1186/s13195-020-0582-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Accepted: 01/05/2020] [Indexed: 12/20/2022]
Abstract
BACKGROUND Metabotropic glutamate subtype 5 receptors (mGluR5) modulate synaptic transmission and may constitute an important therapeutic target in Alzheimer's disease (AD) by mediating the synaptotoxic action of amyloid-β oligomers. We utilized the positron emission tomography (PET) radioligand [18F]FPEB to investigate mGluR5 binding in early AD. METHODS Sixteen individuals with amnestic mild cognitive impairment (MCI) due to AD or mild AD dementia who were positive for brain amyloid were compared to 15 cognitively normal (CN) participants who were negative for brain amyloid. Diagnostic groups were well balanced for age, sex, and education. Dynamic PET scans were acquired for 60 min, starting at 60 min after the initial administration of up to 185 MBq of [18F]FPEB using a bolus-plus-constant-infusion method (Kbol = 190 min). Equilibrium modeling with a cerebellum reference region was used to estimate [18F]FPEB binding (BPND) to mGluR5. Analyses were performed with and without corrections for gray matter atrophy and partial volume effects. RESULTS Linear mixed model analysis demonstrated a significant effect of group (p = 0.011) and the group × region interaction (p = 0.0049) on BPND. Post hoc comparisons revealed a significant reduction (43%) in mGluR5 binding in the hippocampus of AD (BPND = 0.76 ± 0.41) compared to CN (BPND = 1.34 ± 0.58, p = 0.003, unpaired t test) participants, and a nonsignificant trend for a reduction in a composite association cortical region in AD (BPND = 1.57 ± 0.25) compared to CN (BPND = 1.86 ± 0.63, p = 0.093) participants. Exploratory analyses suggested additional mGluR5 reductions in the entorhinal cortex and parahippocampal gyrus in the AD group. In the overall sample, hippocampal mGluR5 binding was associated with episodic memory scores and global function. CONCLUSIONS [18F]FPEB-PET revealed reductions in hippocampal mGluR5 binding in early AD. Quantification of mGluR5 binding in AD may expand our understanding of AD pathogenesis and accelerate the development of novel biomarkers and treatments.
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Affiliation(s)
- Adam P. Mecca
- Alzheimer’s Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT 06510 USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA
| | - Julia W. McDonald
- Alzheimer’s Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT 06510 USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA
| | - Hannah R. Michalak
- Alzheimer’s Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT 06510 USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA
| | - Tyler A. Godek
- Alzheimer’s Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT 06510 USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA
| | - Joanna E. Harris
- Alzheimer’s Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT 06510 USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA
| | - Erika A. Pugh
- Alzheimer’s Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT 06510 USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA
| | - Emily C. Kemp
- Alzheimer’s Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT 06510 USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA
| | - Ming-Kai Chen
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT USA
| | - Arash Salardini
- Department of Neurology, Yale University School of Medicine, New Haven, CT USA
| | - Nabeel B. Nabulsi
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT USA
| | - Keunpoong Lim
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT USA
| | - Yiyun Huang
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT USA
| | - Richard E. Carson
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT USA
| | - Stephen M. Strittmatter
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT USA
- Department of Neurology, Yale University School of Medicine, New Haven, CT USA
- CNNR Program, Yale University School of Medicine, 295 Congress Avenue, Ste 431-435, New Haven, CT USA
| | - Christopher H. van Dyck
- Alzheimer’s Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT 06510 USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT USA
- Department of Neurology, Yale University School of Medicine, New Haven, CT USA
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28
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Beaurain M, Salabert AS, Ribeiro MJ, Arlicot N, Damier P, Le Jeune F, Demonet JF, Payoux P. Innovative Molecular Imaging for Clinical Research, Therapeutic Stratification, and Nosography in Neuroscience. Front Med (Lausanne) 2019; 6:268. [PMID: 31828073 PMCID: PMC6890558 DOI: 10.3389/fmed.2019.00268] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 11/01/2019] [Indexed: 01/06/2023] Open
Abstract
Over the past few decades, several radiotracers have been developed for neuroimaging applications, especially in PET. Because of their low steric hindrance, PET radionuclides can be used to label molecules that are small enough to cross the blood brain barrier, without modifying their biological properties. As the use of 11C is limited by its short physical half-life (20 min), there has been an increasing focus on developing tracers labeled with 18F for clinical use. The first such tracers allowed cerebral blood flow and glucose metabolism to be measured, and the development of molecular imaging has since enabled to focus more closely on specific targets such as receptors, neurotransmitter transporters, and other proteins. Hence, PET and SPECT biomarkers have become indispensable for innovative clinical research. Currently, the treatment options for a number of pathologies, notably neurodegenerative diseases, remain only supportive and symptomatic. Treatments that slow down or reverse disease progression are therefore the subject of numerous studies, in which molecular imaging is proving to be a powerful tool. PET and SPECT biomarkers already make it possible to diagnose several neurological diseases in vivo and at preclinical stages, yielding topographic, and quantitative data about the target. As a result, they can be used for assessing patients' eligibility for new treatments, or for treatment follow-up. The aim of the present review was to map major innovative radiotracers used in neuroscience, and explain their contribution to clinical research. We categorized them according to their target: dopaminergic, cholinergic or serotoninergic systems, β-amyloid plaques, tau protein, neuroinflammation, glutamate or GABA receptors, or α-synuclein. Most neurological disorders, and indeed mental disorders, involve the dysfunction of one or more of these targets. Combinations of molecular imaging biomarkers can afford us a better understanding of the mechanisms underlying disease development over time, and contribute to early detection/screening, diagnosis, therapy delivery/monitoring, and treatment follow-up in both research and clinical settings.
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Affiliation(s)
- Marie Beaurain
- CHU de Toulouse, Toulouse, France.,ToNIC, Toulouse NeuroImaging Center, Inserm U1214, Toulouse, France
| | - Anne-Sophie Salabert
- CHU de Toulouse, Toulouse, France.,ToNIC, Toulouse NeuroImaging Center, Inserm U1214, Toulouse, France
| | - Maria Joao Ribeiro
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France.,Inserm CIC 1415, University Hospital, Tours, France.,CHRU Tours, Tours, France
| | - Nicolas Arlicot
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France.,Inserm CIC 1415, University Hospital, Tours, France.,CHRU Tours, Tours, France
| | - Philippe Damier
- Inserm U913, Neurology Department, University Hospital, Nantes, France
| | | | - Jean-François Demonet
- Leenards Memory Centre, Department of Clinical Neuroscience, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Pierre Payoux
- CHU de Toulouse, Toulouse, France.,ToNIC, Toulouse NeuroImaging Center, Inserm U1214, Toulouse, France
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29
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The pro-psychotic metabotropic glutamate receptor compounds fenobam and AZD9272 share binding sites with monoamine oxidase-B inhibitors in humans. Neuropharmacology 2019; 162:107809. [PMID: 31589885 DOI: 10.1016/j.neuropharm.2019.107809] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Revised: 09/18/2019] [Accepted: 10/02/2019] [Indexed: 11/22/2022]
Abstract
The metabotropic glutamate receptor 5 (mGluR5) ligands fenobam and AZD9272 have been reported to induce psychosis-like adverse events and to bind at unknown, non-GluR5-related, sites. Based on similarities of the regional binding patterns for [11C]AZD9272 and the monoamine oxidase-B (MAO-B) radioligand [11C]L-deprenyl-D2 in PET studies of the human brain we tested the hypothesis that the unique binding of fenobam and AZD9272 may represent specific binding to the MAO-B. PET data previously acquired for subjects examined using [11C]AZD9272 or [11C]L-deprenyl-D2 were re-evaluated to assess the correlations between radioligand binding parameters in human brain. In addition, the pharmacology of AZD9272 binding sites was characterized using competition binding studies carried out in vivo in non-human primates (NHPs) and in vitro using autoradiography in selected human brain regions. The regional binding of [11C]AZD9272 in human brain was closely correlated with that of [11C]L-deprenyl-D2. In PET studies of NHP brain administration of the MAO-B ligand L-deprenyl inhibited binding of radiolabeled AZD9272 and administration of fenobam inhibited binding of [11C]L-deprenyl-D2. Binding of radiolabeled AZD9272 in vitro was potently inhibited by fenobam or MAO-B compounds, and [11C]L-deprenyl-D2 binding was inhibited by fenobam or AZD9272. The findings are consistent with the hypothesis that both fenobam and AZD9272 bind to the MAO-B, which may be of relevance for understanding the mechanism of the psychosis-like adverse events reported for these compounds. Such understanding may serve as a lead to generate new models for the pathophysiology of psychosis.
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30
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AD molecular: Molecular imaging of Alzheimer's disease: PET imaging of neurotransmitter systems. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2019. [PMID: 31481161 DOI: 10.1016/bs.pmbts.2019.04.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Current understanding of Alzheimer's disease (AD) pathogenesis relies on the observed accumulations of amyloid β and phosphorylated tau aggregates that are thought to play key roles in initiating or propagating disease. However, other processes including changes in synaptic proteins and neurotransmitter loss have been suggested as important etiologies or contributors. Positron emission tomography (PET) imaging allows in vivo investigations of molecular changes associated with AD. PET imaging with multiple radiotracers can be used in combination with other modalities such as magnetic resonance imaging (MRI), and with assessments of cognition and neuropsychiatric symptoms to investigate the molecular underpinnings of AD. Studies of synaptic protein changes may improve the understanding of disease mechanisms and provide valuable markers of disease progression and therapeutic efficacy. This chapter will illustrate the importance of in vivo molecular imaging in the study of AD with a specific emphasis on PET and radioligands for several non-amyloid targets.
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31
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Ceccarini J, Leurquin-Sterk G, Crunelle CL, de Laat B, Bormans G, Peuskens H, Van Laere K. Recovery of Decreased Metabotropic Glutamate Receptor 5 Availability in Abstinent Alcohol-Dependent Patients. J Nucl Med 2019; 61:256-262. [PMID: 31481578 DOI: 10.2967/jnumed.119.228825] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 07/19/2019] [Indexed: 12/21/2022] Open
Abstract
Animal models of alcohol dependence and relapse demonstrate an important role of the glutamatergic system, in particular, cerebral metabotropic glutamate receptor 5 (mGluR5). 18F-3-fluoro-5-[(pyridin-3-yl)ethynyl]benzonitrile (18F-FPEB) PET has revealed that chronic alcohol use leads to decreased limbic mGluR5 availability, which was associated with less craving. Here, we tested whether the state of decreased mGluR5 availability in alcohol-dependent patients normalizes during abstinence (at 2 and 6 mo of detoxification) and whether initial mGluR5 imaging parameters can predict individual relapse. Methods: 18F-FPEB scans were performed for 16 recently detoxified alcohol-dependent patients (baseline condition), 2 mo after detoxification (n = 10), and 6 mo after detoxification (n = 8); 32 age- and sex-matched controls were included for comparison. mGluR5 availability was quantified by the 18F-FPEB total distribution volume using both voxel-by-voxel and volume-of-interest analyses. During follow-up, craving was assessed using the Desire for Alcohol Questionnaire, and alcohol consumption was assessed using the timeline follow-back method and monitored by hair ethyl glucuronide analysis. Results: During abstinence, alcohol-dependent patients showed sustained recovered mGluR5 availability in cortical and subcortical regions compared with the baseline, up to the levels observed in controls, after 6 mo in most areas except for the hippocampus, nucleus accumbens, and thalamus. Higher striatopallidal mGluR5 availability was observed at the baseline in patients who had a relapse during the 6-mo follow-up period (+25.1%). Also, normalization of striatal mGluR5 to control levels was associated with reduced craving ("desire and intention to drink" and "negative reinforcement"; r = 0.72-0.94). Conclusion: Reduced cerebral mGluR5 availability in alcohol-dependent patients recovers during abstinence and is associated with reduced craving. Higher striatal mGluR5 availability in alcohol-dependent users may be associated with long-term relapse.
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Affiliation(s)
- Jenny Ceccarini
- Department of Nuclear Medicine and Molecular Imaging, UZ Leuven, Leuven, Belgium .,Department of Imaging and Pathology, KU Leuven, Leuven, Belgium
| | - Gil Leurquin-Sterk
- Department of Nuclear Medicine and Molecular Imaging, UZ Leuven, Leuven, Belgium.,Department of Imaging and Pathology, KU Leuven, Leuven, Belgium
| | - Cleo Lina Crunelle
- Toxicological Center, University of Antwerp, Wilrijk, Belgium.,Department of Psychiatry, Universitair Ziekenhuis Brussel, Brussels, Belgium
| | - Bart de Laat
- Department of Nuclear Medicine and Molecular Imaging, UZ Leuven, Leuven, Belgium.,Department of Imaging and Pathology, KU Leuven, Leuven, Belgium.,MoSAIC, Molecular Small Animal Imaging Center, KU Leuven, Leuven, Belgium
| | - Guy Bormans
- Laboratory for Radiopharmacy, KU Leuven, Leuven, Belgium
| | - Hendrik Peuskens
- University Psychiatric Center, KU Leuven, Kortenberg, Belgium; and.,Kliniek Broeders Alexianen, Tienen, Belgium
| | - Koen Van Laere
- Department of Nuclear Medicine and Molecular Imaging, UZ Leuven, Leuven, Belgium.,Department of Imaging and Pathology, KU Leuven, Leuven, Belgium.,MoSAIC, Molecular Small Animal Imaging Center, KU Leuven, Leuven, Belgium
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32
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Davis MT, Hillmer A, Holmes SE, Pietrzak RH, DellaGioia N, Nabulsi N, Matuskey D, Angarita G, Carson RE, Krystal JH, Esterlis I. In vivo evidence for dysregulation of mGluR5 as a biomarker of suicidal ideation. Proc Natl Acad Sci U S A 2019; 116:11490-11495. [PMID: 31085640 PMCID: PMC6561298 DOI: 10.1073/pnas.1818871116] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Recent evidence implicates dysregulation of metabotropic glutamatergic receptor 5 (mGluR5) in pathophysiology of PTSD and suicidality. Using positron emission tomography and [18F]FPEB, we quantified mGluR5 availability in vivo in individuals with PTSD (n = 29) and MDD (n = 29) as a function of suicidal ideation (SI) to compare with that of healthy comparison controls (HC; n = 29). Volume of distribution was computed using a venous input function in the five key frontal and limbic brain regions. We observed significantly higher mGluR5 availability in PTSD compared with HC individuals in all regions of interest (P's = 0.001-0.01) and compared with MDD individuals in three regions (P's = 0.007). mGluR5 availability was not significantly different between MDD and HC individuals (P = 0.17). Importantly, we observed an up-regulation in mGluR5 availability in the PTSD-SI group (P's = 0.001-0.007) compared with PTSD individuals without SI. Findings point to the potential role for mGluR5 as a target for intervention and, potentially, suicide risk management in PTSD.
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Affiliation(s)
- Margaret T Davis
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06511
| | - Ansel Hillmer
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06511
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT 06520
| | - Sophie E Holmes
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06511
| | - Robert H Pietrzak
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06511
- Clinical Neurosciences Division, National Center for PTSD, US Department of Veterans Affairs, West Haven, CT 06516
| | - Nicole DellaGioia
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06511
| | - Nabeel Nabulsi
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT 06520
| | - David Matuskey
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06511
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT 06520
| | - Gustavo Angarita
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06511
| | - Richard E Carson
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT 06520
| | - John H Krystal
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06511
- Clinical Neurosciences Division, National Center for PTSD, US Department of Veterans Affairs, West Haven, CT 06516
| | - Irina Esterlis
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06511;
- Clinical Neurosciences Division, National Center for PTSD, US Department of Veterans Affairs, West Haven, CT 06516
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33
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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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Kang Y, Henchcliffe C, Verma A, Vallabhajosula S, He B, Kothari PJ, Pryor KO, Mozley PD. 18F-FPEB PET/CT Shows mGluR5 Upregulation in Parkinson's Disease. J Neuroimaging 2018; 29:97-103. [DOI: 10.1111/jon.12563] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Revised: 09/03/2018] [Accepted: 09/04/2018] [Indexed: 11/28/2022] Open
Affiliation(s)
- Yeona Kang
- Department of Radiology; Weill Cornell Medicine; New York NY
| | | | | | | | - Bin He
- Department of Radiology; Weill Cornell Medicine; New York NY
| | | | - Kane O. Pryor
- Department of Anesthesiology; Weill Cornell Medicine; New York NY
| | - P. David Mozley
- Department of Radiology; Weill Cornell Medicine; New York NY
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Varnäs K, Juréus A, Finnema SJ, Johnström P, Raboisson P, Amini N, Takano A, Stepanov V, Halldin C, Farde L. The metabotropic glutamate receptor 5 radioligand [ 11C]AZD9272 identifies unique binding sites in primate brain. Neuropharmacology 2018; 135:455-463. [PMID: 29608920 DOI: 10.1016/j.neuropharm.2018.03.039] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 03/25/2018] [Accepted: 03/29/2018] [Indexed: 12/11/2022]
Abstract
The metabotropic glutamate receptor 5 (mGluR5) is a target for drug development and for imaging studies of the glutamate system in neurological and psychiatric disorders. [11C]AZD9272 is a selective mGluR5 PET radioligand that is structurally different from hitherto applied mGluR5 radioligands. In the present investigation we compared the binding patterns of radiolabeled AZD9272 and other mGluR5 radioligands in the non-human primate (NHP) brain. PET studies were undertaken using [11C]AZD9272 and the commonly applied mGluR5 radioligand [11C]ABP688. Autoradiography studies were performed in vitro using [3H]AZD9272 and the standard mGluR5 radioligands [3H]M-MTEP and [3H]ABP688 in NHP tissue. Competition binding studies were undertaken in vivo and in vitro using different mGluR5 selective compounds as inhibitors. In comparison to other mGluR5 radioligands radiolabeled AZD9272 displayed a distinct regional distribution pattern with high binding in ventral striatum, midbrain, thalamus and cerebellum. While the binding of [11C]AZD9272 was almost completely inhibited by the structurally unique mGluR5 compound fenobam (2.0 mg/kg; 98% occupancy), it was only partially inhibited (46% and 20%, respectively) by the mGluR5 selective compounds ABP688 and MTEP, at a dose (2.0 mg/kg) expected to saturate the mGluR5. Autoradiography studies using [3H]AZD9272 confirmed a distinct pharmacologic profile characterized by preferential sensitivity to fenobam. The distinctive binding in ventral striato-pallido-thalamic circuits and shared pharmacologic profile with the pro-psychotic compound fenobam warrants further examination of [11C]AZD9272 for potential application in psychiatric neuroimaging studies.
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Affiliation(s)
- Katarina Varnäs
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden.
| | | | - Sjoerd J Finnema
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Peter Johnström
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden; PET Science Centre, Precision Medicine and Genomics, IMED Biotech Unit, AstraZeneca, Karolinska Institutet, Sweden
| | | | - Nahid Amini
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Akihiro Takano
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Vladimir Stepanov
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Christer Halldin
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Lars Farde
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden; PET Science Centre, Precision Medicine and Genomics, IMED Biotech Unit, AstraZeneca, Karolinska Institutet, Sweden
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Benlloch JM, González AJ, Pani R, Preziosi E, Jackson C, Murphy J, Barberá J, Correcher C, Aussenhofer S, Gareis D, Visvikis D, Bert J, Langstrom B, Farde L, Toth M, Haggkvist J, Caixeta FV, Kullander K, Somlai-Schweiger I, Schwaiger M. The MINDVIEW project: First results. Eur Psychiatry 2018; 50:21-27. [PMID: 29398564 DOI: 10.1016/j.eurpsy.2018.01.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 01/09/2018] [Accepted: 01/10/2018] [Indexed: 01/01/2023] Open
Abstract
We present the first results of the MINDVIEW project. An innovative imaging system for the human brain examination, allowing simultaneous acquisition of PET/MRI images, has been designed and constructed. It consists of a high sensitivity and high resolution PET scanner integrated in a novel, head-dedicated, radio frequency coil for a 3T MRI scanner. Preliminary measurements from the PET scanner show sensitivity 3 times higher than state-of-the-art PET systems that will allow safe repeated studies on the same patient. The achieved spatial resolution, close to 1 mm, will enable differentiation of relevant brain structures for schizophrenia. A cost-effective and simple method of radiopharmaceutical production from 11C-carbon monoxide and a mini-clean room has been demonstrated. It has been shown that 11C-raclopride has higher binding potential in a new VAAT null mutant mouse model of schizophrenia compared to wild type control animals. A significant reduction in TSPO binding has been found in gray matter in a small sample of drug-naïve, first episode psychosis patients, suggesting a reduced number or an altered function of immune cells in brain at early stage schizophrenia.
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Affiliation(s)
- José M Benlloch
- Institute for Instrumentation in Molecular Imaging (I3 M), Universidad Politécnica de Valencia - CSIC, Valencia, Spain
| | - Antonio J González
- Institute for Instrumentation in Molecular Imaging (I3 M), Universidad Politécnica de Valencia - CSIC, Valencia, Spain.
| | - Roberto Pani
- Department of Molecular Medicine, Sapienza University of Rome, Italy
| | - Enrico Preziosi
- Department of Molecular Medicine, Sapienza University of Rome, Italy
| | | | | | | | | | | | | | - Dimitris Visvikis
- INSERM, UMR1101, LaTIM, Université de Bretagne Occidentale, Brest, France
| | - Julien Bert
- INSERM, UMR1101, LaTIM, Université de Bretagne Occidentale, Brest, France
| | | | - Lars Farde
- Dept. of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden; Precision Medicine & Genomics, AstraZeneca, PET Science Center, Karolinska Institutet, Stockholm, Sweden
| | - Miklos Toth
- Dept. of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Jenny Haggkvist
- Dept. of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Fabio V Caixeta
- Department of Neuroscience, Uppsala University, Uppsala, Sweden
| | - Klas Kullander
- Department of Neuroscience, Uppsala University, Uppsala, Sweden
| | | | - Markus Schwaiger
- Technische Universität München, Dept. of Nuclear Medicine, Munich, Germany
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Warnock G, Sommerauer M, Mu L, Pla Gonzalez G, Geistlich S, Treyer V, Schibli R, Buck A, Krämer SD, Ametamey SM. A first-in-man PET study of [ 18F]PSS232, a fluorinated ABP688 derivative for imaging metabotropic glutamate receptor subtype 5. Eur J Nucl Med Mol Imaging 2017; 45:1041-1051. [PMID: 29177707 DOI: 10.1007/s00259-017-3879-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Accepted: 11/06/2017] [Indexed: 12/21/2022]
Abstract
PURPOSE Non-invasive imaging of metabotropic glutamate receptor 5 (mGlu5) in the brain using PET is of interest in e.g., anxiety, depression, and Parkinson's disease. Widespread application of the most widely used mGlu5 tracer, [11C]ABP688, is limited by the short physical half-life of carbon-11. [18F]PSS232 is a fluorinated analog with promising preclinical properties and high selectivity and specificity for mGlu5. In this first-in-man study, we evaluated the brain uptake pattern and kinetics of [18F]PSS232 in healthy volunteers. METHODS [18F]PSS232 PET was performed with ten healthy male volunteers aged 20-40 years. Seven of the subjects received a bolus injection and the remainder a bolus/infusion protocol. Cerebral blood flow was determined in seven subjects using [15O]water PET. Arterial blood activity was measured using an online blood counter. Tracer kinetics were evaluated by compartment modeling and parametric maps were generated for both tracers. RESULTS At 90 min post-injection, 59.2 ± 11.1% of total radioactivity in plasma corresponded to intact tracer. The regional first pass extraction fraction of [18F]PSS232 ranged from 0.41 ± 0.06 to 0.55 ± 0.03 and brain distribution pattern matched that of [11C]ABP688. Uptake kinetics followed a simple two-tissue compartment model. The volume of distribution of total tracer (V T, ml/cm3) ranged from 1.18 ± 0.20 for white matter to 2.91 ± 0.51 for putamen. The respective mean distribution volume ratios (DVR) with cerebellum as the reference tissue were 0.88 ± 0.06 and 2.12 ± 0.10, respectively. The tissue/cerebellum ratios of a bolus/infusion protocol (30/70 dose ratio) were close to the DVR values. CONCLUSIONS Brain uptake of [18F]PSS232 matched the distribution of mGlu5 and followed a two-tissue compartment model. The well-defined kinetics and the possibility to use reference tissue models, obviating the need for arterial blood sampling, make [18F]PSS232 a promising fluorine-18 labeled radioligand for measuring mGlu5 density in humans.
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Affiliation(s)
- Geoffrey Warnock
- Department of Nuclear Medicine, University Hospital Zurich, 8091, Zurich, Switzerland
| | - Michael Sommerauer
- Department of Nuclear Medicine, University Hospital Zurich, 8091, Zurich, Switzerland.,Department of Neurology, University Hospital Zurich and University of Zurich, Zurich, Switzerland
| | - Linjing Mu
- Department of Nuclear Medicine, University Hospital Zurich, 8091, Zurich, Switzerland
| | - Gloria Pla Gonzalez
- Radiopharmaceutical Science, Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog Weg 4, 8093, Zurich, Switzerland
| | - Susanne Geistlich
- Radiopharmaceutical Science, Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog Weg 4, 8093, Zurich, Switzerland
| | - Valerie Treyer
- Department of Nuclear Medicine, University Hospital Zurich, 8091, Zurich, Switzerland
| | - Roger Schibli
- Radiopharmaceutical Science, Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog Weg 4, 8093, Zurich, Switzerland
| | - Alfred Buck
- Department of Nuclear Medicine, University Hospital Zurich, 8091, Zurich, Switzerland
| | - Stefanie D Krämer
- Radiopharmaceutical Science, Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog Weg 4, 8093, Zurich, Switzerland
| | - Simon M Ametamey
- Radiopharmaceutical Science, Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog Weg 4, 8093, Zurich, Switzerland.
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Imaging the glutamate receptor subtypes-Much achieved, and still much to do. DRUG DISCOVERY TODAY. TECHNOLOGIES 2017; 25:27-36. [PMID: 29233264 DOI: 10.1016/j.ddtec.2017.10.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 10/17/2017] [Accepted: 10/24/2017] [Indexed: 11/20/2022]
Abstract
Functional imaging of glutamate receptors using PET imaging modality can be used to study numerous CNS disorders and also to select appropriate doses of clinically relevant glutamate-receptor-targeting candidate drugs. Great strides have been made in developing PET imaging probes for the non-invasive detection of glutamate receptors in the brain. This review highlights recent progress made towards the development of glutamatergic PET imaging agents. Focus is placed on PET imaging probes that have been labelled with either carbon-11 or fluorine-18.
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DeLorenzo C, Gallezot JD, Gardus J, Yang J, Planeta B, Nabulsi N, Ogden RT, Labaree DC, Huang YH, Mann JJ, Gasparini F, Lin X, Javitch JA, Parsey RV, Carson RE, Esterlis I. In vivo variation in same-day estimates of metabotropic glutamate receptor subtype 5 binding using [ 11C]ABP688 and [ 18F]FPEB. J Cereb Blood Flow Metab 2017; 37:2716-2727. [PMID: 27742888 PMCID: PMC5536783 DOI: 10.1177/0271678x16673646] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 08/02/2016] [Accepted: 09/12/2016] [Indexed: 01/11/2023]
Abstract
Positron emission tomography tracers [11C]ABP688 and [18F]FPEB target the metabotropic glutamate receptor subtype 5 providing quantification of the brain glutamatergic system in vivo. Previous [11C]ABP688 positron emission tomography human test-retest studies indicate that, when performed on the same day, significant binding increases are observed; however, little deviation is reported when scans are >7 days apart. Due to the small cohorts examined previously (eight and five males, respectively), we aimed to replicate the same-day test-retest studies in a larger cohort including both males and females. Results confirmed large within-subject binding differences (ranging from -23% to 108%), suggesting that measurements are greatly affected by study design. We further investigated whether this phenomenon was specific to [11C]ABP688. Using [18F]FPEB and methodology that accounts for residual radioactivity from the test scan, four subjects were scanned twice on the same day. In these subjects, binding estimates increased between 5% and 39% between scans. Consistent with [11C]ABP688, mean absolute test-retest variability was previously reported as <12% when scans were >21 days apart. This replication study and pilot extension to [18F]FPEB suggest that observed within-day binding variation may be due to characteristics of mGluR5; for example, diurnal variation in mGluR5 may affect measurement of this receptor.
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Affiliation(s)
- Christine DeLorenzo
- Department of Psychiatry, Stony Brook University, Stony Brook, USA
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, USA
- Department of Psychiatry, Columbia University, New York, USA
| | | | - John Gardus
- Department of Psychiatry, Stony Brook University, Stony Brook, USA
| | - Jie Yang
- Department of Preventive Medicine, Stony Brook University, Stony Brook, USA
| | - Beata Planeta
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, USA
| | - Nabeel Nabulsi
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, USA
| | - R Todd Ogden
- Department of Psychiatry, Columbia University, New York, USA
| | - David C Labaree
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, USA
| | - Yiyun H Huang
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, USA
| | - J John Mann
- Department of Psychiatry, Columbia University, New York, USA
| | | | - Xin Lin
- Department of Psychiatry, Columbia University, New York, USA
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, USA
| | - Jonathan A Javitch
- Department of Psychiatry, Columbia University, New York, USA
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, USA
- Department of Pharmacology, Columbia University, New York, USA
| | - Ramin V Parsey
- Department of Psychiatry, Stony Brook University, Stony Brook, USA
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, USA
- Department of Radiology, Stony Brook University, Stony Brook, USA
| | - Richard E Carson
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, USA
- Department of Biomedical Engineering, Yale University, New Haven, USA
| | - Irina Esterlis
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, USA
- Department of Psychiatry, Yale University, New Haven, USA
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40
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Altered metabotropic glutamate receptor 5 markers in PTSD: In vivo and postmortem evidence. Proc Natl Acad Sci U S A 2017; 114:8390-8395. [PMID: 28716937 DOI: 10.1073/pnas.1701749114] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Posttraumatic stress disorder (PTSD) is a prevalent and highly disabling disorder, but there is currently no targeted pharmacological treatment for it. Dysfunction of the glutamate system has been implicated in trauma and stress psychopathology, resulting in a growing interest in modulation of the glutamate system for the treatment of PTSD. Specifically, the metabotropic glutamate receptor 5 (mGluR5) represents a promising treatment target. We used [18F]FPEB, a radioligand that binds to the mGluR5, and positron emission tomography (PET) to quantify in vivo mGluR5 availability in human PTSD vs. healthy control (HCs) subjects. In an independent sample of human postmortem tissue, we investigated expression of proteins that have a functional relationship with mGluR5 and glucocorticoids in PTSD. We observed significantly higher cortical mGluR5 availability in PTSD in vivo and positive correlations between mGluR5 availability and avoidance symptoms. In the postmortem sample, we observed up-regulation of SHANK1, a protein that anchors mGluR5 to the cell surface, as well as decreased expression of FKBP5, implicating aberrant glucocorticoid functioning in PTSD. Results of this study provide insight into molecular mechanisms underlying PTSD and suggest that mGluR5 may be a promising target for mechanism-based treatments aimed at mitigating this disorder.
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Lohith TG, Tsujikawa T, Siméon FG, Veronese M, Zoghbi SS, Lyoo CH, Kimura Y, Morse CL, Pike VW, Fujita M, Innis RB. Comparison of two PET radioligands, [ 11C]FPEB and [ 11C]SP203, for quantification of metabotropic glutamate receptor 5 in human brain. J Cereb Blood Flow Metab 2017; 37:2458-2470. [PMID: 27629098 PMCID: PMC5531344 DOI: 10.1177/0271678x16668891] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Of the two 18F-labeled PET ligands currently available to image metabotropic glutamate receptor 5 (mGluR5), [18F]FPEB is reportedly superior because [18F]SP203 undergoes glutathionlyation, generating [18F]-fluoride ion that accumulates in brain and skull. To allow multiple PET studies on the same day with lower radiation exposure, we prepared [11C]FPEB and [11C]SP203 from [11C]hydrogen cyanide and compared their abilities to accurately quantify mGluR5 in human brain, especially as regards radiometabolite accumulation. Genomic plot was used to estimate the ratio of specific-to-nondisplaceable uptake ( BPND) without using a receptor blocking drug. Both tracers quantified mGluR5; however [11C]SP203, like [18F]SP203, had radiometabolite accumulation in brain, as evidenced by increased distribution volume ( VT) over the scan period. Absolute VT values were ∼30% lower for 11C-labeled compared with 18F-labeled radioligands, likely caused by the lower specific activities (and high receptor occupancies) of the 11C radioligands. The genomic plot indicated ∼60% specific binding in cerebellum, which makes it inappropriate as a reference region. Whole-body scans performed in healthy subjects demonstrated a low radiation burden typical for 11C-ligands. Thus, the evidence suggests that [11C]FPEB is superior to [11C]SP203. If prepared in higher specific activity, [11C]FPEB would presumably be as effective as [18F]FPEB for quantifying mGluR5 in human brain.
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Affiliation(s)
- Talakad G Lohith
- 1 Molecular Imaging Branch, National Institute of Mental Health, Bethesda, USA
| | - Tetsuya Tsujikawa
- 1 Molecular Imaging Branch, National Institute of Mental Health, Bethesda, USA
| | - Fabrice G Siméon
- 1 Molecular Imaging Branch, National Institute of Mental Health, Bethesda, USA
| | - Mattia Veronese
- 1 Molecular Imaging Branch, National Institute of Mental Health, Bethesda, USA.,2 Department of Neuroimaging, King's College London, London, UK
| | - Sami S Zoghbi
- 1 Molecular Imaging Branch, National Institute of Mental Health, Bethesda, USA
| | - Chul Hyoung Lyoo
- 1 Molecular Imaging Branch, National Institute of Mental Health, Bethesda, USA
| | - Yasuyuki Kimura
- 1 Molecular Imaging Branch, National Institute of Mental Health, Bethesda, USA
| | - Cheryl L Morse
- 1 Molecular Imaging Branch, National Institute of Mental Health, Bethesda, USA
| | - Victor W Pike
- 1 Molecular Imaging Branch, National Institute of Mental Health, Bethesda, USA
| | - Masahiro Fujita
- 1 Molecular Imaging Branch, National Institute of Mental Health, Bethesda, USA
| | - Robert B Innis
- 1 Molecular Imaging Branch, National Institute of Mental Health, Bethesda, USA
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Metabotropic Glutamate Receptor 5 and Glutamate Involvement in Major Depressive Disorder: A Multimodal Imaging Study. BIOLOGICAL PSYCHIATRY: COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2017; 2:449-456. [PMID: 28993818 DOI: 10.1016/j.bpsc.2017.03.019] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND Preclinical and postmortem studies have implicated the metabotropic glutamate receptor 5 (mGluR5) in the pathophysiology of major depressive disorder (MDD). The goal of the present study was to determine the role of mGluR5 in a large group of individuals with MDD compared to healthy controls (HC) in vivo with [18F]FPEB and positron emission tomography (PET). Furthermore, we sought to determine the role glutamate plays on mGluR5 availability in MDD. METHODS Sixty-five participants (30 MDD and 35 HC) completed [18F]FPEB PET to estimate the primary outcome measure - mGluR5 volume of distribution (VT), and the secondary outcome measure - mGluR5 distribution volume ratio (DVR). A subgroup of 39 participants (16 MDD and 23 HC) completed proton magnetic resonance spectroscopy (1H MRS) to estimate anterior cingulate (ACC) glutamate, glutamine, and Glx (glutamate + glutamine) levels relative to creatine (Cr). RESULTS No significant between-group differences were observed in mGluR5 VT or DVR. Compared to HC, individuals with MDD had higher ACC glutamate, glutamine, and Glx levels. Importantly, the ACC mGluR5 DVR negatively correlated with glutamate/Cr and Glx/Cr levels. CONCLUSIONS In this novel in vivo examination, we show an inverse relationship between mGluR5 availability and glutamate levels. These data highlight the need to further investigate the role of glutamatergic system in depression.
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Shimoda Y, Yamasaki T, Fujinaga M, Ogawa M, Kurihara Y, Nengaki N, Kumata K, Yui J, Hatori A, Xie L, Zhang Y, Kawamura K, Zhang MR. Synthesis and Evaluation of Novel Radioligands Based on 3-[5-(Pyridin-2-yl)-2H-tetrazol-2-yl]benzonitrile for Positron Emission Tomography Imaging of Metabotropic Glutamate Receptor Subtype 5. J Med Chem 2016; 59:3980-90. [DOI: 10.1021/acs.jmedchem.6b00209] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Yoko Shimoda
- Department
of Radiopharmaceuticals Development, Radiological Science Research
and Development Directorate, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Tomoteru Yamasaki
- Department
of Radiopharmaceuticals Development, Radiological Science Research
and Development Directorate, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Masayuki Fujinaga
- Department
of Radiopharmaceuticals Development, Radiological Science Research
and Development Directorate, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Masanao Ogawa
- Department
of Radiopharmaceuticals Development, Radiological Science Research
and Development Directorate, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
- SHI Accelerator
Service Co. Ltd., 1-17-6 Osaki, Shinagawa-ku, Tokyo 141-0032, Japan
| | - Yusuke Kurihara
- Department
of Radiopharmaceuticals Development, Radiological Science Research
and Development Directorate, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
- SHI Accelerator
Service Co. Ltd., 1-17-6 Osaki, Shinagawa-ku, Tokyo 141-0032, Japan
| | - Nobuki Nengaki
- Department
of Radiopharmaceuticals Development, Radiological Science Research
and Development Directorate, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
- SHI Accelerator
Service Co. Ltd., 1-17-6 Osaki, Shinagawa-ku, Tokyo 141-0032, Japan
| | - Katsushi Kumata
- Department
of Radiopharmaceuticals Development, Radiological Science Research
and Development Directorate, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Joji Yui
- Department
of Radiopharmaceuticals Development, Radiological Science Research
and Development Directorate, 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, Radiological Science Research
and Development Directorate, 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, Radiological Science Research
and Development Directorate, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Yiding Zhang
- Department
of Radiopharmaceuticals Development, Radiological Science Research
and Development Directorate, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Kazunori Kawamura
- Department
of Radiopharmaceuticals Development, Radiological Science Research
and Development Directorate, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Ming-Rong Zhang
- Department
of Radiopharmaceuticals Development, Radiological Science Research
and Development Directorate, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
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Leurquin-Sterk G, Postnov A, de Laat B, Casteels C, Celen S, Crunelle CL, Bormans G, Koole M, Van Laere K. Kinetic modeling and long-term test-retest reproducibility of the mGluR5 PET tracer18F-FPEB in human brain. Synapse 2016; 70:153-62. [DOI: 10.1002/syn.21890] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 01/15/2016] [Accepted: 01/15/2016] [Indexed: 12/12/2022]
Affiliation(s)
- Gil Leurquin-Sterk
- Division of Nuclear Medicine; KU Leuven - University of Leuven and University Hospital Leuven; Herestraat 49 Leuven 3000 Belgium
| | - Andrey Postnov
- Division of Nuclear Medicine; KU Leuven - University of Leuven and University Hospital Leuven; Herestraat 49 Leuven 3000 Belgium
| | - Bart de Laat
- Division of Nuclear Medicine; KU Leuven - University of Leuven and University Hospital Leuven; Herestraat 49 Leuven 3000 Belgium
- MoSAIC, Molecular Small Animal Imaging Center, KU Leuven - University of Leuven; Leuven Belgium
| | - Cindy Casteels
- Division of Nuclear Medicine; KU Leuven - University of Leuven and University Hospital Leuven; Herestraat 49 Leuven 3000 Belgium
- MoSAIC, Molecular Small Animal Imaging Center, KU Leuven - University of Leuven; Leuven Belgium
| | - Sofie Celen
- Laboratory for Radiopharmacy, KU Leuven - University of Leuven; Leuven Belgium
| | | | - Guy Bormans
- Laboratory for Radiopharmacy, KU Leuven - University of Leuven; Leuven Belgium
| | - Michel Koole
- Division of Nuclear Medicine; KU Leuven - University of Leuven and University Hospital Leuven; Herestraat 49 Leuven 3000 Belgium
- MoSAIC, Molecular Small Animal Imaging Center, KU Leuven - University of Leuven; Leuven Belgium
| | - Koen Van Laere
- Division of Nuclear Medicine; KU Leuven - University of Leuven and University Hospital Leuven; Herestraat 49 Leuven 3000 Belgium
- MoSAIC, Molecular Small Animal Imaging Center, KU Leuven - University of Leuven; Leuven Belgium
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Arsenault D, Coulombe K, Zhu A, Gong C, Kil KE, Choi JK, Poutiainen P, Brownell AL. Loss of Metabotropic Glutamate Receptor 5 Function on Peripheral Benzodiazepine Receptor in Mice Prenatally Exposed to LPS. PLoS One 2015; 10:e0142093. [PMID: 26536027 PMCID: PMC4633140 DOI: 10.1371/journal.pone.0142093] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 10/16/2015] [Indexed: 11/18/2022] Open
Abstract
Parental microglial induced neuroinflammation, triggered by bacterial- or viral infections, can induce neuropsychiatric disorders like schizophrenia and autism to offspring in animal models. Recent investigations suggest that microglia, the resident immune cells of the brain, provides a link between neurotransmission, immune cell activation, brain inflammation and neuronal dysfunction seen with the offspring. Relatively little is known about how reduction of brain inflammation and restoration of glial function are associated with diminution of brain degeneration and behavioral deficits in offspring. Increased mGluR5 expression and the long-lasting excitotoxic effects of the neurotoxin during brain development are associated with the glial dysfunctions. We investigated the relationship of mGluR5 and PBR and how they regulate glial function and inflammatory processes in mice prenatally exposed to LPS (120μg/kg, between gestational days 15 and 17), an inflammatory model of a psychiatric disorder. Using PET imaging, we showed that pharmacological activation of mGluR5 during 5 weeks reduced expression of classic inflammation marker PBR in many brain areas and that this molecular association was not present in LPS-exposed offspring. The post-mortem analysis revealed that the down regulation of PBR was mediated through activation of mGluR5 in astrocytes. In addition, we demonstrated that this interaction is defective in a mouse model of the psychiatric deficit offering a novel insight of mGluR5 involvement to brain related disorders and PBR related imaging studies. In conclusion, mGluR5 driven glutamatergic activity regulates astrocytic functions associated with PBR (cholesterol transport, neurosteroidogenesis, glial phenotype) during maturation and could be associated with neuropsychiatric disorders in offspring.
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Affiliation(s)
- Dany Arsenault
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, United States of America
| | - Katherine Coulombe
- Centre de Recherche du CHU de Québec, Axe Neurosciences, Faculté de Pharmacie, Université Laval, Québec, QC, Canada
| | - Aijun Zhu
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, United States of America
| | - Chunyu Gong
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, United States of America
| | - Kun-Eek Kil
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, United States of America
| | - Ji-Kyung Choi
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, United States of America
| | - Pekka Poutiainen
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, United States of America
| | - Anna-Liisa Brownell
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, United States of America
- * E-mail:
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Hillmer AT, Mason GF, Fucito LM, O'Malley SS, Cosgrove KP. How Imaging Glutamate, γ-Aminobutyric Acid, and Dopamine Can Inform the Clinical Treatment of Alcohol Dependence and Withdrawal. Alcohol Clin Exp Res 2015; 39:2268-82. [PMID: 26510169 DOI: 10.1111/acer.12893] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 08/29/2015] [Indexed: 12/29/2022]
Abstract
Neuroimaging studies have dramatically advanced our understanding of the neurochemical basis of alcohol dependence, a major public health issue. In this paper, we review the research generated from neurochemical specific imaging modalities including magnetic resonance spectroscopy, positron emission tomography, and single-photon emission computed tomography in studies of alcohol dependence and withdrawal. We focus on studies interrogating γ-aminobutyric acid (GABA), glutamate, and dopamine, as these are prominent neurotransmitter systems implicated in alcohol dependence. Highlighted findings include diminished dopaminergic functioning and modulation of the GABA system by tobacco smoking during alcohol withdrawal. Then, we consider how these findings impact the clinical treatment of alcohol dependence and discuss directions for future experiments to address existing gaps in the literature, for example, sex differences and smoking comorbidity. These and other considerations provide opportunities to build upon the current neurochemistry imaging literature of alcohol dependence and withdrawal, which may usher in improved therapeutic and relapse prevention strategies.
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Affiliation(s)
- Ansel T Hillmer
- Departments of Psychiatry and Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut
| | - Graeme F Mason
- Departments of Psychiatry and Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut
| | - Lisa M Fucito
- Departments of Psychiatry and Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut
| | - Stephanie S O'Malley
- Departments of Psychiatry and Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut
| | - Kelly P Cosgrove
- Departments of Psychiatry and Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut
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Calderwood S, Collier TL, Gouverneur V, Liang SH, Vasdev N. Synthesis of 18F-Arenes from Spirocyclic Iodonium(III) Ylides via Continuous-Flow Microfluidics. J Fluor Chem 2015; 178:249-253. [PMID: 27512233 PMCID: PMC4976495 DOI: 10.1016/j.jfluchem.2015.08.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Spirocyclic hypervalent iodine(III) ylides have proven to be synthetically versatile precursors for efficient radiolabelling of a diverse range of non-activated (hetero)arenes, highly functionalised small molecules, building blocks and radiopharmaceuticals from [18F]fluoride ion. Herein, we report the implementation of these reactions onto a continuous-flow microfluidic platform, thereby offering an alterative and automated synthetic procedure of a radiopharmaceutical, 3-[18F]fluoro-5-[(pyridin-3-yl)ethynyl]benzonitrile ([18F]FPEB) and a routinely used building block for click-radiochemistry, 4-[18F]fluorobenzyl azide. This new protocol was applied to the synthesis of [18F]FPEB (radiochemical conversion (RCC) = 68 ± 5%) and 4-[18F]fluorobenzyl azide (RCC=68 ± 5%; isolated radiochemical yield = 24±0%). We anticipate that the high throughput microfluidic platform will accelerate the discovery and applications of 18F-labelled building blocks and labelled compounds prepared by iodonium ylide precursors as well as the production of radiotracers for preclinical imaging studies.
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Affiliation(s)
- Samuel Calderwood
- University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford, UK
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, 55 Fruit Street, Boston, USA
| | - Thomas Lee Collier
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, 55 Fruit Street, Boston, USA
- Department of Radiology, Harvard Medical School, 55 Fruit Street, Boston, USA
- Advion BioSystems, 10 Brown Road, Suite 101, Ithaca, New York, USA
| | - Véronique Gouverneur
- University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford, UK
| | - Steven H. Liang
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, 55 Fruit Street, Boston, USA
- Department of Radiology, Harvard Medical School, 55 Fruit Street, Boston, USA
| | - Neil Vasdev
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, 55 Fruit Street, Boston, USA
- Department of Radiology, Harvard Medical School, 55 Fruit Street, Boston, USA
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de Laat B, Leurquin-Sterk G, Celen S, Bormans G, Koole M, Van Laere K, Casteels C. Preclinical Evaluation and Quantification of 18F-FPEB as a Radioligand for PET Imaging of the Metabotropic Glutamate Receptor 5. J Nucl Med 2015; 56:1954-9. [PMID: 26405172 DOI: 10.2967/jnumed.115.162636] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 09/10/2015] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED The metabotropic glutamate receptor 5 (mGluR5) is a high-interest target for PET imaging because it plays a role in several pathologies, including addiction, schizophrenia, and fragile X syndrome. METHODS We studied the pharmacokinetics of (18)F-FPEB (3-(18)F-fluoro-5-(2-pyridinylethynyl)benzonitrile), a selective PET radioligand for mGluR5, and used it to quantify mGluR5 in rat brain. Quantification was performed using both arterial sampling in combination with compartment models and simplified reference methods. The simplified reference tissue model (SRTM), Ichise's original multi-linear reference tissue model (MRTMO), and Logan noninvasive were tested as reference models with nondisplaceable binding (BPND) as outcome parameter. Additionally, test-retest scans were obtained in 6 animals. RESULTS (18)F-FPEB uptake in rat brain was consistent with its known distribution. No radiometabolites were present in the brain, and binding was specific as shown in blocking experiments, which also confirmed the cerebellum as a viable reference region. A 2-tissue-compartment model was used to determine BPND for the striatum (11.7 ± 1.5), nucleus accumbens (10.6 ± 2.0), hippocampus (9.0 ± 1.2), cortex (7.2 ± 1.0), and thalamus (4.0 ± 0.9). Reference methods were able to estimate these values with small bias (<2%). Test-retest analysis showed high repeatability between scans below 6%, also for shorter scan durations of 30 and 60 min. CONCLUSION Because of its favorable reversible kinetics, high specificity, and absence of brain radiometabolites (18)F-FPEB proves a highly useful tracer for in vivo visualization of the mGluR5 in rat brain. Moreover, reference tissue models allow noninvasive, rapid scanning with good test-retest.
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Affiliation(s)
- Bart de Laat
- KU Leuven-University of Leuven, MoSAIC, Molecular Small Animal Imaging Center, Leuven, Belgium KU Leuven-University of Leuven/University Hospital Leuven, Division of Nuclear Medicine, Leuven, Belgium; and
| | - Gil Leurquin-Sterk
- KU Leuven-University of Leuven/University Hospital Leuven, Division of Nuclear Medicine, Leuven, Belgium; and
| | - Sofie Celen
- KU Leuven-University of Leuven, MoSAIC, Molecular Small Animal Imaging Center, Leuven, Belgium KU Leuven-University of Leuven, Laboratory for Radiopharmacy, Leuven, Belgium
| | - Guy Bormans
- KU Leuven-University of Leuven, MoSAIC, Molecular Small Animal Imaging Center, Leuven, Belgium KU Leuven-University of Leuven, Laboratory for Radiopharmacy, Leuven, Belgium
| | - Michel Koole
- KU Leuven-University of Leuven, MoSAIC, Molecular Small Animal Imaging Center, Leuven, Belgium KU Leuven-University of Leuven/University Hospital Leuven, Division of Nuclear Medicine, Leuven, Belgium; and
| | - Koen Van Laere
- KU Leuven-University of Leuven, MoSAIC, Molecular Small Animal Imaging Center, Leuven, Belgium KU Leuven-University of Leuven/University Hospital Leuven, Division of Nuclear Medicine, Leuven, Belgium; and
| | - Cindy Casteels
- KU Leuven-University of Leuven, MoSAIC, Molecular Small Animal Imaging Center, Leuven, Belgium KU Leuven-University of Leuven/University Hospital Leuven, Division of Nuclear Medicine, Leuven, Belgium; and
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Park E, Sullivan JM, Planeta B, Gallezot JD, Lim K, Lin SF, Ropchan J, McCarthy TJ, Ding YS, Morris ED, Williams WA, Huang Y, Carson RE. Test-retest reproducibility of the metabotropic glutamate receptor 5 ligand [¹⁸F]FPEB with bolus plus constant infusion in humans. Eur J Nucl Med Mol Imaging 2015; 42:1530-41. [PMID: 26044120 DOI: 10.1007/s00259-015-3094-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 05/21/2015] [Indexed: 12/12/2022]
Abstract
PURPOSE [(18)F]FPEB is a promising PET radioligand for the metabotropic glutamate receptor 5 (mGluR5), a potential target for the treatment of neuropsychiatric diseases. The purpose of this study was to evaluate the test-retest reproducibility of [(18)F]FPEB in the human brain. METHODS Seven healthy male subjects were scanned twice, 3 - 11 weeks apart. Dynamic data were acquired using bolus plus infusion of 162 ± 32 MBq [(18)F]FPEB. Four methods were used to estimate volume of distribution (V T): equilibrium analysis (EQ) using arterial (EQA) or venous input data (EQV), MA1, and a two-tissue compartment model (2 T). Binding potential (BP ND) was also estimated using cerebellar white matter (CWM) or gray matter (CGM) as the reference region using EQ, 2 T and MA1. Absolute test-retest variability (aTRV) of V T and BP ND were calculated for each method. Venous blood measurements (C V) were compared with arterial input (C A) to examine their usability in EQ analysis. RESULTS Regional V T estimated by the four methods displayed a high degree of agreement (r (2) ranging from 0.83 to 0.99 among the methods), although EQA and EQV overestimated V T by a mean of 9 % and 7 %, respectively, compared to 2 T. Mean values of aTRV of V T were 11 % by EQA, 12 % by EQV, 14 % by MA1 and 14 % by 2 T. Regional BP ND also agreed well among the methods and mean aTRV of BP ND was 8 - 12 % (CWM) and 7 - 9 % (CGM). Venous and arterial blood concentrations of [(18)F]FPEB were well matched during equilibrium (C V = 1.01 · C A, r (2) = 0.95). CONCLUSION [(18)F]FPEB binding shows good TRV with minor differences among analysis methods. Venous blood can be used as an alternative for input function measurement instead of arterial blood in EQ analysis. Thus, [(18)F]FPEB is an excellent PET imaging tracer for mGluR5 in humans.
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Affiliation(s)
- Eunkyung Park
- PET Center, Department of Diagnostic Radiology, Yale School of Medicine, 801 Howard Avenue, PO Box 208048, New Haven, CT, 06520-8048, USA,
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Hae Kang J, Lee M, Hoon Ryu Y, Hyoung Lyoo C, Hoon Kim C, Chul Lee K, Hyun Choi T, Yong Choi J. [18F]FPEB and [18F]FDEGPECO comparative study of mGlu5 quantification in rodent brain. Appl Radiat Isot 2015; 98:103-7. [DOI: 10.1016/j.apradiso.2015.01.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 01/21/2015] [Accepted: 01/25/2015] [Indexed: 02/01/2023]
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