1
|
Wall MB, Harding R, Zafar R, Rabiner EA, Nutt DJ, Erritzoe D. Neuroimaging in psychedelic drug development: past, present, and future. Mol Psychiatry 2023; 28:3573-3580. [PMID: 37759038 PMCID: PMC10730398 DOI: 10.1038/s41380-023-02271-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 09/13/2023] [Indexed: 09/29/2023]
Abstract
Psychedelic therapy (PT) is an emerging paradigm with great transdiagnostic potential for treating psychiatric disorders, including depression, addiction, post-traumatic stress disorder, and potentially others. 'Classic' serotonergic psychedelics, such as psilocybin and lysergic acid diethylamide (LSD), which have a key locus of action at the 5-HT2A receptor, form the main focus of this movement, but substances including ketamine, 3,4-Methylenedioxymethamphetamine (MDMA) and ibogaine also hold promise. The modern phase of development of these treatment modalities in the early 21st century has occurred concurrently with the wider use of advanced human neuroscientific research methods; principally neuroimaging. This can potentially enable assessment of drug and therapy brain effects with greater precision and quantification than any previous novel development in psychiatric pharmacology. We outline the major trends in existing data and suggest the modern development of PT has benefitted greatly from the use of neuroimaging. Important gaps in existing knowledge are identified, namely: the relationship between acute drug effects and longer-term (clinically-relevant) effects, the precise characterisation of effects at the 5-HT2A receptor and relationships with functional/clinical effects, and the possible impact of these compounds on neuroplasticity. A road-map for future research is laid out, outlining clinical studies which will directly address these three questions, principally using combined Positron Emission Tomography (PET) and Magnetic Resonance Imaging (MRI) methods, plus other adjunct techniques. Multimodal (PET/MRI) studies using modern PET techniques such as the 5-HT2A-selective ligand [11 C]Cimbi-36 (and other ligands sensitive to neuroplasticity changes) alongside MRI measures of brain function would provide a 'molecular-functional-clinical bridge' in understanding. Such results would help to resolve some of these questions and provide a firmer foundation for the ongoing development of PT.
Collapse
Affiliation(s)
- Matthew B Wall
- Invicro, London, UK.
- Faculty of Medicine, Imperial College London, London, UK.
- Centre for Psychedelic research and Neuropsychopharmacology, Imperial College London, London, UK.
| | - Rebecca Harding
- Clinical Psychopharmacology Unit, Faculty of Brain Sciences, University College London, London, UK
| | - Rayyan Zafar
- Faculty of Medicine, Imperial College London, London, UK
- Centre for Psychedelic research and Neuropsychopharmacology, Imperial College London, London, UK
| | | | - David J Nutt
- Faculty of Medicine, Imperial College London, London, UK
- Centre for Psychedelic research and Neuropsychopharmacology, Imperial College London, London, UK
| | - David Erritzoe
- Faculty of Medicine, Imperial College London, London, UK
- Centre for Psychedelic research and Neuropsychopharmacology, Imperial College London, London, UK
| |
Collapse
|
2
|
Zafar R, Siegel M, Harding R, Barba T, Agnorelli C, Suseelan S, Roseman L, Wall M, Nutt DJ, Erritzoe D. Psychedelic therapy in the treatment of addiction: the past, present and future. Front Psychiatry 2023; 14:1183740. [PMID: 37377473 PMCID: PMC10291338 DOI: 10.3389/fpsyt.2023.1183740] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 05/15/2023] [Indexed: 06/29/2023] Open
Abstract
Psychedelic therapy has witnessed a resurgence in interest in the last decade from the scientific and medical communities with evidence now building for its safety and efficacy in treating a range of psychiatric disorders including addiction. In this review we will chart the research investigating the role of these interventions in individuals with addiction beginning with an overview of the current socioeconomic impact of addiction, treatment options, and outcomes. We will start by examining historical studies from the first psychedelic research era of the mid-late 1900s, followed by an overview of the available real-world evidence gathered from naturalistic, observational, and survey-based studies. We will then cover modern-day clinical trials of psychedelic therapies in addiction from first-in-human to phase II clinical trials. Finally, we will provide an overview of the different translational human neuropsychopharmacology techniques, including functional magnetic resonance imaging (fMRI) and positron emission tomography (PET), that can be applied to foster a mechanistic understanding of therapeutic mechanisms. A more granular understanding of the treatment effects of psychedelics will facilitate the optimisation of the psychedelic therapy drug development landscape, and ultimately improve patient outcomes.
Collapse
Affiliation(s)
- Rayyan Zafar
- Centre for Psychedelic Research, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
- Neuropsychopharmacology Unit, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Maxim Siegel
- Centre for Psychedelic Research, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
- Neuropsychopharmacology Unit, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Rebecca Harding
- Clinical Psychopharmacology Unit, University College London, London, United Kingdom
| | - Tommaso Barba
- Centre for Psychedelic Research, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
- Neuropsychopharmacology Unit, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Claudio Agnorelli
- Centre for Psychedelic Research, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
- Neuropsychopharmacology Unit, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Shayam Suseelan
- Centre for Psychedelic Research, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
- Neuropsychopharmacology Unit, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Leor Roseman
- Centre for Psychedelic Research, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
- Neuropsychopharmacology Unit, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Matthew Wall
- Centre for Psychedelic Research, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
- Neuropsychopharmacology Unit, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
- Invicro, London, United Kingdom
| | - David John Nutt
- Centre for Psychedelic Research, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
- Neuropsychopharmacology Unit, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - David Erritzoe
- Centre for Psychedelic Research, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
- Neuropsychopharmacology Unit, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
| |
Collapse
|
3
|
Herian M, Świt P. 25X-NBOMe compounds - chemistry, pharmacology and toxicology. A comprehensive review. Crit Rev Toxicol 2023; 53:15-33. [PMID: 37115704 DOI: 10.1080/10408444.2023.2194907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Recently, a growing number of reports have indicated a positive effect of hallucinogenic-based therapies in different neuropsychiatric disorders. However, hallucinogens belonging to the group of new psychoactive substances (NPS) may produce high toxicity. NPS, due to their multi-receptors affinity, are extremely dangerous for the human body and mental health. An example of hallucinogens that have been lately responsible for many severe intoxications and deaths are 25X-NBOMes - N-(2-methoxybenzyl)-2,5-dimethoxy-4-substituted phenethylamines, synthetic compounds with strong hallucinogenic properties. 25X-NBOMes exhibit a high binding affinity to serotonin receptors but also to dopamine, adrenergic and histamine receptors. Apart from their influence on perception, many case reports point out systemic and neurological poisoning with these compounds. In humans, the most frequent side effects are tachycardia, anxiety, hypertension and seizures. Moreover, preclinical studies confirm that 25X-NBOMes cause developmental impairments, cytotoxicity, cardiovascular toxicity and changes in behavior of animals. Metabolism of NBOMes seems to be very complex and involves many metabolic pathways. This fact may explain the observed high toxicity. In addition, many analytical methods have been applied in order to identify these compounds and their metabolites. The presented review summarized the current knowledge about 25X-NBOMes, especially in the context of toxicity.
Collapse
Affiliation(s)
- Monika Herian
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Paweł Świt
- Institute of Chemistry, Faculty of Science and Technology, University of Silesia, Katowice, Poland
| |
Collapse
|
4
|
Singh P, Singh D, Srivastava P, Mishra G, Tiwari AK. Evaluation of advanced, pathophysiologic new targets for imaging of CNS. Drug Dev Res 2023; 84:484-513. [PMID: 36779375 DOI: 10.1002/ddr.22040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Revised: 12/12/2022] [Accepted: 12/31/2022] [Indexed: 02/14/2023]
Abstract
The inadequate information about the in vivo pathological, physiological, and neurological impairments, as well as the absence of in vivo tools for assessing brain penetrance and the efficiency of newly designed drugs, has hampered the development of new techniques for the treatment for variety of new central nervous system (CNS) diseases. The searching sites such as Science Direct and PubMed were used to find out the numerous distinct tracers across 16 CNS targets including tau, synaptic vesicle glycoprotein, the adenosine 2A receptor, the phosphodiesterase enzyme PDE10A, and the purinoceptor, among others. Among the most encouraging are [18 F]FIMX for mGluR imaging, [11 C]Martinostat for Histone deacetylase, [18 F]MNI-444 for adenosine 2A imaging, [11 C]ER176 for translocator protein, and [18 F]MK-6240 for tau imaging. We also reviewed the findings for each tracer's features and potential for application in CNS pathophysiology and therapeutic evaluation investigations, including target specificity, binding efficacy, and pharmacokinetic factors. This review aims to present a current evaluation of modern positron emission tomography tracers for CNS targets, with a focus on recent advances for targets that have newly emerged for imaging in humans.
Collapse
Affiliation(s)
- Priya Singh
- Department of Chemistry, Babasaheb Bhimrao Ambedkar University, Lucknow, Uttar Pradesh, India
| | - Deepika Singh
- Department of Chemistry, Babasaheb Bhimrao Ambedkar University, Lucknow, Uttar Pradesh, India
| | - Pooja Srivastava
- Division of Cyclotron and Radiopharmaceuticals Sciences, Institute of Nuclear Medicine and Allied Sciences, Delhi, India
| | - Gauri Mishra
- Department of Zoology, Swami Shraddhananad College, University of Delhi, Alipur, Delhi, India
| | - Anjani K Tiwari
- Department of Chemistry, Babasaheb Bhimrao Ambedkar University, Lucknow, Uttar Pradesh, India
| |
Collapse
|
5
|
Søndergaard A, Madsen MK, Ozenne B, Armand S, Knudsen GM, Fisher PM, Stenbæk DS. Lasting increases in trait mindfulness after psilocybin correlate positively with the mystical-type experience in healthy individuals. Front Psychol 2022; 13:948729. [PMID: 36275302 PMCID: PMC9580465 DOI: 10.3389/fpsyg.2022.948729] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 09/16/2022] [Indexed: 11/13/2022] Open
Abstract
Background Psilocybin-induced mystical-type experiences are associated with lasting positive psychological outcomes. Recent studies indicate that trait mindfulness is increased 3 months after psilocybin intake, preceded by decreases in neocortical serotonin 2A receptor (5-HT2AR) binding. However, the association between psilocybin-induced mystical-type experiences and subsequent changes in trait mindfulness remains unexplored, as does the association between pre-drug trait mindfulness and 5-HT2AR binding in the healthy brain. Aim We evaluated whether psilocybin induced lasting increases in trait mindfulness in healthy volunteers, and whether the mystical-type experience was associated with this increase. We further examined the association between pre-drug trait mindfulness and 5-HT2AR binding in neocortex and selected frontolimbic regions. Materials and methods Forty-six medium-high dose psilocybin sessions were conducted in 39 healthy individuals. The mystical-type experience was measured with the Mystical Experience Questionnaire (MEQ) at the end of the session. Trait mindfulness was measured using the Mindful Attention and Awareness Scale (MAAS) at baseline and 3 months after the psilocybin session. Thirty-two of the participants completed pre-drug [11C]-Cimbi-36 positron emission tomography (PET) to assess 5-HT2AR binding in neocortex and, post-hoc, in the frontolimbic regions amygdala, frontal cortex, and anterior cingulate cortex. Results The MAAS score was significantly increased at 3-month follow-up (p = 3.24 × 10–6), a change positively associated with the MEQ score (p = 0.035). Although the association between pre-drug MAAS score and neocortex 5-HT2AR binding was not significant (p = 0.24), post-hoc analyses revealed a significant negative association between MAAS and right amygdala 5-HT2AR binding (pFWER = 0.008). Conclusion We here show that lasting changes in trait mindfulness following psilocybin administration are positively associated with intensity of the mystical-type experience, suggesting that the acute phenomenology of psilocybin facilitates a shift in awareness conducive for mindful living. We furthermore show that higher pre-drug trait mindfulness is associated with reduced 5-HT2AR binding in the right amygdala.
Collapse
Affiliation(s)
- Anna Søndergaard
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Martin Korsbak Madsen
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Department of Psychiatry, University Hospital Svendborg, Svendborg, Denmark
| | - Brice Ozenne
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Sophia Armand
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Institute of Psychology, University of Copenhagen, Copenhagen, Denmark
| | - Gitte Moos Knudsen
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Patrick MacDonald Fisher
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Dea Siggaard Stenbæk
- Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Institute of Psychology, University of Copenhagen, Copenhagen, Denmark
- *Correspondence: Dea Siggaard Stenbæk,
| |
Collapse
|
6
|
Fu H, Rong J, Chen Z, Zhou J, Collier T, Liang SH. Positron Emission Tomography (PET) Imaging Tracers for Serotonin Receptors. J Med Chem 2022; 65:10755-10808. [PMID: 35939391 DOI: 10.1021/acs.jmedchem.2c00633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Serotonin (5-hydroxytryptamine, 5-HT) and 5-HT receptors (5-HTRs) have crucial roles in various neuropsychiatric disorders and neurodegenerative diseases, making them attractive diagnostic and therapeutic targets. Positron emission tomography (PET) is a noninvasive nuclear molecular imaging technique and is an essential tool in clinical diagnosis and drug discovery. In this context, numerous PET ligands have been developed for "visualizing" 5-HTRs in the brain and translated into human use to study disease mechanisms and/or support drug development. Herein, we present a comprehensive repertoire of 5-HTR PET ligands by focusing on their chemotypes and performance in PET imaging studies. Furthermore, this Perspective summarizes recent 5-HTR-focused drug discovery, including biased agonists and allosteric modulators, which would stimulate the development of more potent and subtype-selective 5-HTR PET ligands and thus further our understanding of 5-HTR biology.
Collapse
Affiliation(s)
- Hualong Fu
- Key Laboratory of Radiopharmaceuticals, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Jian Rong
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, Boston, Massachusetts 02114, United States.,Department of Radiology, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Zhen Chen
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing, Jiangsu 210037, China
| | - Jingyin Zhou
- Key Laboratory of Radiopharmaceuticals, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Thomas Collier
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, Boston, Massachusetts 02114, United States.,Department of Radiology, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Steven H Liang
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, Boston, Massachusetts 02114, United States.,Department of Radiology, Harvard Medical School, Boston, Massachusetts 02115, United States
| |
Collapse
|
7
|
Crișan G, Moldovean-Cioroianu NS, Timaru DG, Andrieș G, Căinap C, Chiș V. Radiopharmaceuticals for PET and SPECT Imaging: A Literature Review over the Last Decade. Int J Mol Sci 2022; 23:ijms23095023. [PMID: 35563414 PMCID: PMC9103893 DOI: 10.3390/ijms23095023] [Citation(s) in RCA: 61] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Revised: 04/23/2022] [Accepted: 04/28/2022] [Indexed: 02/04/2023] Open
Abstract
Positron emission tomography (PET) uses radioactive tracers and enables the functional imaging of several metabolic processes, blood flow measurements, regional chemical composition, and/or chemical absorption. Depending on the targeted processes within the living organism, different tracers are used for various medical conditions, such as cancer, particular brain pathologies, cardiac events, and bone lesions, where the most commonly used tracers are radiolabeled with 18F (e.g., [18F]-FDG and NA [18F]). Oxygen-15 isotope is mostly involved in blood flow measurements, whereas a wide array of 11C-based compounds have also been developed for neuronal disorders according to the affected neuroreceptors, prostate cancer, and lung carcinomas. In contrast, the single-photon emission computed tomography (SPECT) technique uses gamma-emitting radioisotopes and can be used to diagnose strokes, seizures, bone illnesses, and infections by gauging the blood flow and radio distribution within tissues and organs. The radioisotopes typically used in SPECT imaging are iodine-123, technetium-99m, xenon-133, thallium-201, and indium-111. This systematic review article aims to clarify and disseminate the available scientific literature focused on PET/SPECT radiotracers and to provide an overview of the conducted research within the past decade, with an additional focus on the novel radiopharmaceuticals developed for medical imaging.
Collapse
Affiliation(s)
- George Crișan
- Faculty of Physics, Babeş-Bolyai University, Str. M. Kogălniceanu 1, 400084 Cluj-Napoca, Romania; (G.C.); (N.S.M.-C.); (D.-G.T.)
- Department of Nuclear Medicine, County Clinical Hospital, Clinicilor 3-5, 400006 Cluj-Napoca, Romania;
| | | | - Diana-Gabriela Timaru
- Faculty of Physics, Babeş-Bolyai University, Str. M. Kogălniceanu 1, 400084 Cluj-Napoca, Romania; (G.C.); (N.S.M.-C.); (D.-G.T.)
| | - Gabriel Andrieș
- Department of Nuclear Medicine, County Clinical Hospital, Clinicilor 3-5, 400006 Cluj-Napoca, Romania;
| | - Călin Căinap
- The Oncology Institute “Prof. Dr. Ion Chiricuţă”, Republicii 34-36, 400015 Cluj-Napoca, Romania;
| | - Vasile Chiș
- Faculty of Physics, Babeş-Bolyai University, Str. M. Kogălniceanu 1, 400084 Cluj-Napoca, Romania; (G.C.); (N.S.M.-C.); (D.-G.T.)
- Institute for Research, Development and Innovation in Applied Natural Sciences, Babeș-Bolyai University, Str. Fântânele 30, 400327 Cluj-Napoca, Romania
- Correspondence:
| |
Collapse
|
8
|
McCulloch DEW, Madsen MK, Stenbæk DS, Kristiansen S, Ozenne B, Jensen PS, Knudsen GM, Fisher PM. Lasting effects of a single psilocybin dose on resting-state functional connectivity in healthy individuals. J Psychopharmacol 2022; 36:74-84. [PMID: 34189985 PMCID: PMC8801642 DOI: 10.1177/02698811211026454] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
BACKGROUND Psilocybin is a psychedelic drug that has shown lasting positive effects on clinical symptoms and self-reported well-being following a single dose. There has been little research into the long-term effects of psilocybin on brain connectivity in humans. AIM Evaluate changes in resting-state functional connectivity (RSFC) at 1 week and 3 months after one psilocybin dose in 10 healthy psychedelic-naïve volunteers and explore associations between change in RSFC and related measures. METHODS Participants received 0.2-0.3 mg/kg psilocybin in a controlled setting. Participants completed resting-state functional magnetic resonance imaging (fMRI) scans at baseline, 1-week and 3-month post-administration and [11C]Cimbi-36 PET scans at baseline and 1 week. We examined changes in within-network, between-network and region-to-region RSFC. We explored associations between changes in RSFC and psilocybin-induced phenomenology as well as changes in psychological measures and neocortex serotonin 2A receptor binding. RESULTS Psilocybin was well tolerated and produced positive changes in well-being. At 1 week only, executive control network (ECN) RSFC was significantly decreased (Cohen's d = -1.73, pFWE = 0.010). We observed no other significant changes in RSFC at 1 week or 3 months, nor changes in region-to-region RSFC. Exploratory analyses indicated that decreased ECN RSFC at 1 week predicted increased mindfulness at 3 months (r = -0.65). CONCLUSIONS These findings in a small cohort indicate that psilocybin affects ECN function within the psychedelic 'afterglow' period. Our findings implicate ECN modulation as mediating psilocybin-induced, long-lasting increases in mindfulness. Although our findings implicate a neural pathway mediating lasting psilocybin effects, it is notable that changes in neuroimaging measures at 3 months, when personality changes are observed, remain to be identified.
Collapse
Affiliation(s)
| | - Martin Korsbak Madsen
- Neurobiology Research Unit and NeuroPharm, Rigshospitalet, Copenhagen, Denmark,Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Dea Siggaard Stenbæk
- Neurobiology Research Unit and NeuroPharm, Rigshospitalet, Copenhagen, Denmark,Department of Psychology, University of Copenhagen, Copenhagen, Denmark
| | - Sara Kristiansen
- Neurobiology Research Unit and NeuroPharm, Rigshospitalet, Copenhagen, Denmark
| | - Brice Ozenne
- Neurobiology Research Unit and NeuroPharm, Rigshospitalet, Copenhagen, Denmark,Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Peter Steen Jensen
- Neurobiology Research Unit and NeuroPharm, Rigshospitalet, Copenhagen, Denmark
| | - Gitte Moos Knudsen
- Neurobiology Research Unit and NeuroPharm, Rigshospitalet, Copenhagen, Denmark,Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Patrick MacDonald Fisher
- Neurobiology Research Unit and NeuroPharm, Rigshospitalet, Copenhagen, Denmark,Patrick MacDonald Fisher, Neurobiology Research Unit, Rigshospitalet Building 8057, 8 Inge Lehmanns Vej, Copenhagen 2100, Denmark.
| |
Collapse
|
9
|
Zeng F, Nye JA, Voll RJ, Mun J, Goodman MM. Synthesis and Evaluation of [ 11C]7-Halogen-2-Phenyl Isoindolone Derivatives: Potential PET Radioligands for in vivo Imaging of 5-HT 2 C Receptors. Front Neurosci 2021; 15:766320. [PMID: 34899169 PMCID: PMC8661056 DOI: 10.3389/fnins.2021.766320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Accepted: 11/03/2021] [Indexed: 11/13/2022] Open
Abstract
The serotonin 5-HT2C receptor (5-HT2CR) is abundantly expressed throughout the central nervous system, and involved in a variety of neuroendocrine and neurobehavioral processes. The development of a selective radioligand that will enable in vivo imaging and quantification of 5-HT2CR densities represents a significant technological advancement in understanding both the normal function and pathophysiology of the 5-HT2CR. Four 7-halogen-2-phenyl isoindolones (7-F, Cl, Br, I) were synthesized and displayed high affinities for 5-HT2CR and high selectivity over 5-HT2A and 5-HT2B. [11C]7-Chloro-2-[4-methoxy-3-[2-(4-methylpiperidin-1-yl)ethoxy]phenyl]isoindolin-1-one (6) and [11C]7-iodo-2-[4-methoxy-3-[2-(4-methylpiperidin-1-yl)ethoxy]phenyl]isoindolin-1-one (9) were synthesized in high radiochemical yield of 37–44% [n = 10, decay corrected from end of (11C)CH3I synthesis] with high radiochemical purity via O-methylation with [11C]CH3I, respectively. MicroPET imaging studies in male rats with or without 5-HT2C antagonist SB-242084 showed that [11C]6 and [11C]9 display specific bindings to 5-HT2CR in the choroid plexus and hippocampus. In vivo microPET brain imaging studies in rhesus monkeys demonstrated that [11C]6 and [11C]9 exhibit excellent blood-brain barrier penetration. The contrast of bindings to the choroid plexus and hippocampus compared to the cerebellum peaked at 2.7 and 1.6, respectively, for [11C]6, and 3.7 and 2.7, respectively, for [11C]9, which were reduced by administration of a dose of SB-242084. Our results support the candidacy of [11C]6 and [11C]9 for further study as radioligands for in vivo quantitation of 5-HT2C sites by PET.
Collapse
Affiliation(s)
- Fanxing Zeng
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, United States
| | - Jonathon A Nye
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, United States.,Center for Systems Imaging, Emory University, Atlanta, GA, United States
| | - Ronald J Voll
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, United States.,Center for Systems Imaging, Emory University, Atlanta, GA, United States
| | - Jiyoung Mun
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, United States
| | - Mark M Goodman
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, United States.,Center for Systems Imaging, Emory University, Atlanta, GA, United States
| |
Collapse
|
10
|
Jucaite A, Stenkrona P, Cselényi Z, De Vita S, Buil-Bruna N, Varnäs K, Savage A, Varrone A, Johnström P, Schou M, Davison C, Sykes A, Pilla Reddy V, Hoch M, Vazquez-Romero A, Moein MM, Halldin C, Merchant MS, Pass M, Farde L. Brain exposure of the ATM inhibitor AZD1390 in humans-a positron emission tomography study. Neuro Oncol 2021; 23:687-696. [PMID: 33123736 DOI: 10.1093/neuonc/noaa238] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND The protein kinase ataxia telangiectasia mutated (ATM) mediates cellular response to DNA damage induced by radiation. ATM inhibition decreases DNA damage repair in tumor cells and affects tumor growth. AZD1390 is a novel, highly potent, selective ATM inhibitor designed to cross the blood-brain barrier (BBB) and currently evaluated with radiotherapy in a phase I study in patients with brain malignancies. In the present study, PET was used to measure brain exposure of 11C-labeled AZD1390 after intravenous (i.v.) bolus administration in healthy subjects with an intact BBB. METHODS AZD1390 was radiolabeled with carbon-11 and a microdose (mean injected mass 1.21 µg) was injected in 8 male subjects (21-65 y). The radioactivity concentration of [11C]AZD1390 in brain was measured using a high-resolution PET system. Radioactivity in arterial blood was measured to obtain a metabolite corrected arterial input function for quantitative image analysis. Participants were monitored by laboratory examinations, vital signs, electrocardiogram, adverse events. RESULTS The brain radioactivity concentration of [11C]AZD1390 was 0.64 SUV (standard uptake value) and reached maximum 1.00% of injected dose at Tmax[brain] of 21 min (time of maximum brain radioactivity concentration) after i.v. injection. The whole brain total distribution volume was 5.20 mL*cm-3. No adverse events related to [11C]AZD1390 were reported. CONCLUSIONS This study demonstrates that [11C]AZD1390 crosses the intact BBB and supports development of AZD1390 for the treatment of glioblastoma multiforme or other brain malignancies. Moreover, it illustrates the potential of PET microdosing in predicting and guiding dose range and schedule for subsequent clinical studies.
Collapse
Affiliation(s)
- Aurelija Jucaite
- PET Science Centre, Precision Medicine and Biosamples, R&D, AstraZeneca, Stockholm, Sweden.,Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Per Stenkrona
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Zsolt Cselényi
- PET Science Centre, Precision Medicine and Biosamples, R&D, AstraZeneca, Stockholm, Sweden.,Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | | | - Nuria Buil-Bruna
- Clinical Pharmacology and Quantitative Pharmacology, Clinical Pharmacology and Safety Sciences, R&D, AstraZeneca, Cambridge, UK
| | - Katarina Varnäs
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | | | - Andrea Varrone
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Peter Johnström
- PET Science Centre, Precision Medicine and Biosamples, R&D, AstraZeneca, Stockholm, Sweden.,Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Magnus Schou
- PET Science Centre, Precision Medicine and Biosamples, R&D, AstraZeneca, Stockholm, Sweden.,Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | | | - Andy Sykes
- Oncology R&D, AstraZeneca, Cambridge, UK
| | | | - Matthias Hoch
- Clinical Pharmacology and Quantitative Pharmacology, Clinical Pharmacology and Safety Sciences, R&D, AstraZeneca, Cambridge, UK
| | - Ana Vazquez-Romero
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Mohammad Mahdi Moein
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Christer Halldin
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | | | | | - Lars Farde
- PET Science Centre, Precision Medicine and Biosamples, R&D, AstraZeneca, Stockholm, Sweden.,Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| |
Collapse
|
11
|
Cumming P, Scheidegger M, Dornbierer D, Palner M, Quednow BB, Martin-Soelch C. Molecular and Functional Imaging Studies of Psychedelic Drug Action in Animals and Humans. Molecules 2021; 26:2451. [PMID: 33922330 PMCID: PMC8122807 DOI: 10.3390/molecules26092451] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 04/15/2021] [Accepted: 04/19/2021] [Indexed: 12/19/2022] Open
Abstract
Hallucinogens are a loosely defined group of compounds including LSD, N,N-dimethyltryptamines, mescaline, psilocybin/psilocin, and 2,5-dimethoxy-4-methamphetamine (DOM), which can evoke intense visual and emotional experiences. We are witnessing a renaissance of research interest in hallucinogens, driven by increasing awareness of their psychotherapeutic potential. As such, we now present a narrative review of the literature on hallucinogen binding in vitro and ex vivo, and the various molecular imaging studies with positron emission tomography (PET) or single photon emission computer tomography (SPECT). In general, molecular imaging can depict the uptake and binding distribution of labelled hallucinogenic compounds or their congeners in the brain, as was shown in an early PET study with N1-([11C]-methyl)-2-bromo-LSD ([11C]-MBL); displacement with the non-radioactive competitor ketanserin confirmed that the majority of [11C]-MBL specific binding was to serotonin 5-HT2A receptors. However, interactions at serotonin 5HT1A and other classes of receptors and pleotropic effects on second messenger pathways may contribute to the particular experiential phenomenologies of LSD and other hallucinogenic compounds. Other salient aspects of hallucinogen action include permeability to the blood-brain barrier, the rates of metabolism and elimination, and the formation of active metabolites. Despite the maturation of radiochemistry and molecular imaging in recent years, there has been only a handful of PET or SPECT studies of radiolabeled hallucinogens, most recently using the 5-HT2A/2C agonist N-(2[11CH3O]-methoxybenzyl)-2,5-dimethoxy- 4-bromophenethylamine ([11C]Cimbi-36). In addition to PET studies of target engagement at neuroreceptors and transporters, there is a small number of studies on the effects of hallucinogenic compounds on cerebral perfusion ([15O]-water) or metabolism ([18F]-fluorodeoxyglucose/FDG). There remains considerable scope for basic imaging research on the sites of interaction of hallucinogens and their cerebrometabolic effects; we expect that hybrid imaging with PET in conjunction with functional magnetic resonance imaging (fMRI) should provide especially useful for the next phase of this research.
Collapse
Affiliation(s)
- Paul Cumming
- Department of Nuclear Medicine, Bern University Hospital, CH-3010 Bern, Switzerland
- School of Psychology and Counselling, Queensland University of Technology, Brisbane 4059, Australia
| | - Milan Scheidegger
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital of the University of Zurich, CH-8032 Zurich, Switzerland; (M.S.); (D.D.); (B.B.Q.)
| | - Dario Dornbierer
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital of the University of Zurich, CH-8032 Zurich, Switzerland; (M.S.); (D.D.); (B.B.Q.)
| | - Mikael Palner
- Odense Department of Clinical Research, University of Southern Denmark, DK-5000 Odense, Denmark;
- Department of Nuclear Medicine, Odense University Hospital, DK-5000 Odense, Denmark
- Neurobiology Research Unit, Copenhagen University Hospital, DK-2100 Copenhagen, Denmark
| | - Boris B. Quednow
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital of the University of Zurich, CH-8032 Zurich, Switzerland; (M.S.); (D.D.); (B.B.Q.)
- Neuroscience Center Zurich, University of Zurich and Swiss Federal Institute of Technology Zurich, CH-8058 Zurich, Switzerland
| | | |
Collapse
|
12
|
Kinetic isotope effects and synthetic strategies for deuterated carbon-11 and fluorine-18 labelled PET radiopharmaceuticals. Nucl Med Biol 2021; 96-97:112-147. [PMID: 33892374 DOI: 10.1016/j.nucmedbio.2021.03.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 03/19/2021] [Accepted: 03/30/2021] [Indexed: 11/22/2022]
Abstract
The deuterium labelling of pharmaceuticals is a useful strategy for altering pharmacokinetic properties, particularly for improving metabolic resistance. The pharmacological effects of such metabolites are often assumed to be negligible during standard drug discovery and are factored in later at the clinical phases of development, where the risks and benefits of the treatment and side-effects can be wholly assessed. This paradigm does not translate to the discovery of radiopharmaceuticals, however, as the confounding effects of radiometabolites can inevitably show in preliminary positron emission tomography (PET) scans and thus complicate interpretation. Consequently, the formation of radiometabolites is crucial to take into consideration, compared to non-radioactive metabolites, and the application of deuterium labelling is a particularly attractive approach to minimise radiometabolite formation. Herein, we provide a comprehensive overview of the deuterated carbon-11 and fluorine-18 radiopharmaceuticals employed in PET imaging experiments. Specifically, we explore six categories of deuterated radiopharmaceuticals used to investigate the activities of monoamine oxygenase (MAO), choline, translocator protein (TSPO), vesicular monoamine transporter 2 (VMAT2), neurotransmission and the diagnosis of Alzheimer's disease; from which we derive four prominent deuteration strategies giving rise to a kinetic isotope effect (KIE) for reducing the rate of metabolism. Synthetic approaches for over thirty of these deuterated radiopharmaceuticals are discussed from the perspective of deuterium and radioisotope incorporation, alongside an evaluation of the deuterium labelling and radiolabelling efficacies across these independent studies. Clinical and manufacturing implications are also discussed to provide a more comprehensive overview of how deuterated radiopharmaceuticals may be introduced to routine practice.
Collapse
|
13
|
de Natale ER, Wilson H, Politis M. Serotonergic imaging in Parkinson's disease. PROGRESS IN BRAIN RESEARCH 2021; 261:303-338. [PMID: 33785134 DOI: 10.1016/bs.pbr.2020.11.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder characterized by the progressive degeneration of monoaminergic central pathways such as the serotonergic. The degeneration of serotonergic signaling in striatal and extrastriatal brain regions is an early feature of PD and is associated with several motor and non-motor complications of the disease. Molecular imaging techniques with Positron Emission Tomography (PET) have greatly contributed to the investigation of biological changes in vivo and to the understanding of the extent of serotonergic pathology in patients or individuals at risk for PD. Such discoveries provide with opportunities for the identification of new targets that can be used for the development of novel disease-modifying drugs or symptomatic treatments. Future studies of imaging serotonergic molecular targets will better clarify the importance of serotonergic pathology in PD, including progression of pathology, target-identification for pharmacotherapy, and relevance to endogenous synaptic serotonin levels. In this article, we review the current status and understanding of serotonergic imaging in PD.
Collapse
Affiliation(s)
| | - Heather Wilson
- Neurodegeneration Imaging Group, University of Exeter Medical School, London, United Kingdom
| | - Marios Politis
- Neurodegeneration Imaging Group, University of Exeter Medical School, London, United Kingdom.
| |
Collapse
|
14
|
Raval NR, Johansen A, Donovan LL, Ros NF, Ozenne B, Hansen HD, Knudsen GM. A Single Dose of Psilocybin Increases Synaptic Density and Decreases 5-HT 2A Receptor Density in the Pig Brain. Int J Mol Sci 2021; 22:E835. [PMID: 33467676 PMCID: PMC7830000 DOI: 10.3390/ijms22020835] [Citation(s) in RCA: 88] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 01/11/2021] [Accepted: 01/12/2021] [Indexed: 02/06/2023] Open
Abstract
A single dose of psilocybin, a psychedelic and serotonin 2A receptor (5-HT2AR) agonist, may be associated with antidepressant effects. The mechanism behind its antidepressive action is unknown but could be linked to increased synaptogenesis and down-regulation of cerebral 5-HT2AR. Here, we investigate if a single psychedelic dose of psilocybin changes synaptic vesicle protein 2A (SV2A) and 5-HT2AR density in the pig brain. Twenty-four awake pigs received either 0.08 mg/kg psilocybin or saline intravenously. Twelve pigs (n = 6/intervention) were euthanized one day post-injection, while the remaining twelve pigs were euthanized seven days post-injection (n = 6/intervention). We performed autoradiography on hippocampus and prefrontal cortex (PFC) sections with [3H]UCB-J (SV2A), [3H]MDL100907 (5-HT2AR antagonist) and [3H]Cimbi-36 (5-HT2AR agonist). One day post psilocybin injection, we observed 4.42% higher hippocampal SV2A density and lowered hippocampal and PFC 5-HT2AR density (-15.21% to -50.19%). These differences were statistically significant in the hippocampus for all radioligands and in the PFC for [3H]Cimbi-36 only. Seven days post-intervention, there was still significantly higher SV2A density in the hippocampus (+9.24%) and the PFC (+6.10%), whereas there were no longer any differences in 5-HT2AR density. Our findings suggest that psilocybin causes increased persistent synaptogenesis and an acute decrease in 5-HT2AR density, which may play a role in psilocybin's antidepressive effects.
Collapse
Affiliation(s)
- Nakul Ravi Raval
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark; (N.R.R.); (A.J.); (L.L.D.); (N.F.R.); (B.O.); (H.D.H.)
- Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Annette Johansen
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark; (N.R.R.); (A.J.); (L.L.D.); (N.F.R.); (B.O.); (H.D.H.)
- Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Lene Lundgaard Donovan
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark; (N.R.R.); (A.J.); (L.L.D.); (N.F.R.); (B.O.); (H.D.H.)
- Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Nídia Fernandez Ros
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark; (N.R.R.); (A.J.); (L.L.D.); (N.F.R.); (B.O.); (H.D.H.)
| | - Brice Ozenne
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark; (N.R.R.); (A.J.); (L.L.D.); (N.F.R.); (B.O.); (H.D.H.)
- Department of Public Health, Section of Biostatistics, Faculty of Health and Medical Sciences, University of Copenhagen, 1014 Copenhagen, Denmark
| | - Hanne Demant Hansen
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark; (N.R.R.); (A.J.); (L.L.D.); (N.F.R.); (B.O.); (H.D.H.)
- A. A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Gitte Moos Knudsen
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark; (N.R.R.); (A.J.); (L.L.D.); (N.F.R.); (B.O.); (H.D.H.)
- Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| |
Collapse
|
15
|
Cumming P, Gründer G, Brinson Z, Wong DF. Applications, Advances, and Limitations of Molecular Imaging of Brain Receptors. Mol Imaging 2021. [DOI: 10.1016/b978-0-12-816386-3.00063-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
|
16
|
Sex and the serotonergic underpinnings of depression and migraine. HANDBOOK OF CLINICAL NEUROLOGY 2020; 175:117-140. [PMID: 33008520 DOI: 10.1016/b978-0-444-64123-6.00009-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Most psychiatric disorders demonstrate sex differences in their prevalence and symptomatology, and in their response to treatment. These differences are particularly pronounced in mood disorders. Differences in sex hormone levels are among the most overt distinctions between males and females and are thus an intuitive underpinning for these clinical observations. In fact, treatment with estrogen and testosterone was shown to exert antidepressant effects, which underscores this link. Changes to monoaminergic signaling in general, and serotonergic transmission in particular, are understood as central components of depressive pathophysiology. Thus, modulation of the serotonin system may serve as a mechanism via which sex hormones exert their clinical effects in mental health disorders. Over the past 20 years, various experimental approaches have been applied to identify modes of influence of sex and sex hormones on the serotonin system. This chapter provides an overview of different molecular components of the serotonin system, followed by a review of studies performed in animals and in humans with the purpose of elucidating sex hormone effects. Particular emphasis will be placed on studies performed with positron emission tomography, a method that allows for human in vivo molecular imaging and, therefore, assessment of effects in a clinically representative context. The studies addressed in this chapter provide a wealth of information on the interaction between sex, sex hormones, and serotonin in the brain. In general, they offer evidence for the concept that the influence of sex hormones on various components of the serotonin system may serve as an underpinning for the clinical effects these hormones demonstrate.
Collapse
|
17
|
Spies M, Nasser A, Ozenne B, Jensen PS, Knudsen GM, Fisher PM. Common HTR2A variants and 5-HTTLPR are not associated with human in vivo serotonin 2A receptor levels. Hum Brain Mapp 2020; 41:4518-4528. [PMID: 32697408 PMCID: PMC7555071 DOI: 10.1002/hbm.25138] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 05/08/2020] [Accepted: 06/16/2020] [Indexed: 12/22/2022] Open
Abstract
The serotonin 2A receptor (5‐HT2AR) is implicated in the pathophysiology and treatment of various psychiatric disorders. [18F]altanserin and [11C]Cimbi‐36 positron emission tomography (PET) allow for high‐resolution imaging of 5‐HT2AR in the living human brain. Cerebral 5‐HT2AR binding is strongly genetically determined, though the impact of specific variants is poorly understood. Candidate gene studies suggest that HTR2A single nucleotide polymorphisms including rs6311/rs6313, rs6314, and rs7997012 may influence risk for psychiatric disorders and mediate treatment response. Although known to impact in vitro expression of 5‐HT2AR or other serotonin (5‐HT) proteins, their effect on human in vivo brain 5‐HT2AR binding has as of yet been insufficiently studied. We thus assessed the extent to which these variants and the commonly studied 5‐HTTLPR predict neocortex in vivo 5‐HT2AR binding in healthy adult humans. We used linear regression analyses and likelihood ratio tests in 197 subjects scanned with [18F]altanserin or [11C]Cimbi‐36 PET. Although we observed genotype group differences in 5‐HT2AR binding of up to ~10%, no genetic variants were statistically significantly predictive of 5‐HT2AR binding in what is the largest human in vivo 5‐HT2AR imaging genetics study to date. Thus, in vitro and post mortem results suggesting effects on 5‐HT2AR expression did not carry over to the in vivo setting. To any extent these variants might affect clinical risk, our findings do not support that 5‐HT2AR binding mediates such effects. Our observations indicate that these individual variants do not significantly contribute to genetic load on human in vivo 5‐HT2AR binding.
Collapse
Affiliation(s)
- Marie Spies
- Neurobiology Research Unit, Rigshospitalet, Copenhagen, Denmark.,Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
| | - Arafat Nasser
- Neurobiology Research Unit, Rigshospitalet, Copenhagen, Denmark
| | - Brice Ozenne
- Neurobiology Research Unit, Rigshospitalet, Copenhagen, Denmark.,Department of Public Health, Section of Biostatistics, University of Copenhagen, Copenhagen, Denmark
| | - Peter S Jensen
- Neurobiology Research Unit, Rigshospitalet, Copenhagen, Denmark
| | - Gitte M Knudsen
- Neurobiology Research Unit, Rigshospitalet, Copenhagen, Denmark
| | | |
Collapse
|
18
|
Madsen MK, Fisher PM, Stenbæk DS, Kristiansen S, Burmester D, Lehel S, Páleníček T, Kuchař M, Svarer C, Ozenne B, Knudsen GM. A single psilocybin dose is associated with long-term increased mindfulness, preceded by a proportional change in neocortical 5-HT2A receptor binding. Eur Neuropsychopharmacol 2020; 33:71-80. [PMID: 32146028 DOI: 10.1016/j.euroneuro.2020.02.001] [Citation(s) in RCA: 76] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Revised: 02/03/2020] [Accepted: 02/17/2020] [Indexed: 12/19/2022]
Abstract
A single dose of the serotonin 2A receptor (5-HT2AR) agonist psilocybin can have long-lasting beneficial effects on mood, personality, and potentially on mindfulness, but underlying mechanisms are unknown. Here, we for the first time conduct a study that assesses psilocybin effects on cerebral 5-HT2AR binding with [11C]Cimbi-36 positron emission tomography (PET) imaging and on personality and mindfulness. Ten healthy and psychedelic-naïve volunteers underwent PET neuroimaging of 5-HT2AR at baseline (BL) and one week (1W) after a single oral dose of psilocybin (0.2-0.3 mg/kg). Personality (NEO PI-R) and mindfulness (MAAS) questionnaires were completed at BL and at three-months follow-up (3M). Paired t-tests revealed statistically significant increases in personality Openness (puncorrected = 0.04, mean change [95%CI]: 4.2[0.4;∞]), which was hypothesized a priori to increase, and mindfulness (pFWER = 0.02, mean change [95%CI]: 0.5 [0.2;0.7]). Although 5-HT2AR binding at 1W versus BL was similar across individuals (puncorrected = 0.8, mean change [95%CI]: 0.007 [-0.04;0.06]), a post hoc linear regression analysis showed that change in mindfulness and 5-HT2AR correlated negatively (β [95%CI] = -5.0 [-9.0; -0.9], pFWER= 0.046). In conclusion, we confirm that psilocybin intake is associated with long-term increases in Openness and - as a novel finding - mindfulness, which may be a key element of psilocybin therapy. Cerebral 5-HT2AR binding did not change across individuals but the negative association between changes in 5-HT2AR binding and mindfulness suggests that individual change in 5-HT2AR levels after psilocybin is variable and represents a potential mechanism influencing long-term effects of psilocybin on mindfulness.
Collapse
Affiliation(s)
- Martin Korsbak Madsen
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Patrick MacDonald Fisher
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark
| | - Dea Siggaard Stenbæk
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark
| | - Sara Kristiansen
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark
| | - Daniel Burmester
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Szabolcs Lehel
- PET and Cyclotron Unit, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark
| | - Tomas Páleníček
- National Institute of Mental Health, 250 67 Klecany, Czech Republic
| | - Martin Kuchař
- National Institute of Mental Health, 250 67 Klecany, Czech Republic; Forensic Laboratory of Biologically Active Substances, Department of Chemistry of Natural Compounds, University of Chemistry and Technology, 166 28 Prague, Czech Republic
| | - Claus Svarer
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark
| | - Brice Ozenne
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark; Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Gitte M Knudsen
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark.
| |
Collapse
|
19
|
McCluskey SP, Plisson C, Rabiner EA, Howes O. Advances in CNS PET: the state-of-the-art for new imaging targets for pathophysiology and drug development. Eur J Nucl Med Mol Imaging 2020; 47:451-489. [PMID: 31541283 PMCID: PMC6974496 DOI: 10.1007/s00259-019-04488-0] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 08/15/2019] [Indexed: 02/07/2023]
Abstract
PURPOSE A limit on developing new treatments for a number of central nervous system (CNS) disorders has been the inadequate understanding of the in vivo pathophysiology underlying neurological and psychiatric disorders and the lack of in vivo tools to determine brain penetrance, target engagement, and relevant molecular activity of novel drugs. Molecular neuroimaging provides the tools to address this. This article aims to provide a state-of-the-art review of new PET tracers for CNS targets, focusing on developments in the last 5 years for targets recently available for in-human imaging. METHODS We provide an overview of the criteria used to evaluate PET tracers. We then used the National Institute of Mental Health Research Priorities list to identify the key CNS targets. We conducted a PubMed search (search period 1st of January 2013 to 31st of December 2018), which yielded 40 new PET tracers across 16 CNS targets which met our selectivity criteria. For each tracer, we summarised the evidence of its properties and potential for use in studies of CNS pathophysiology and drug evaluation, including its target selectivity and affinity, inter and intra-subject variability, and pharmacokinetic parameters. We also consider its potential limitations and missing characterisation data, but not specific applications in drug development. Where multiple tracers were present for a target, we provide a comparison of their properties. RESULTS AND CONCLUSIONS Our review shows that multiple new tracers have been developed for proteinopathy targets, particularly tau, as well as the purinoceptor P2X7, phosphodiesterase enzyme PDE10A, and synaptic vesicle glycoprotein 2A (SV2A), amongst others. Some of the most promising of these include 18F-MK-6240 for tau imaging, 11C-UCB-J for imaging SV2A, 11C-CURB and 11C-MK-3168 for characterisation of fatty acid amide hydrolase, 18F-FIMX for metabotropic glutamate receptor 1, and 18F-MNI-444 for imaging adenosine 2A. Our review also identifies recurrent issues within the field. Many of the tracers discussed lack in vivo blocking data, reducing confidence in selectivity. Additionally, late-stage identification of substantial off-target sites for multiple tracers highlights incomplete pre-clinical characterisation prior to translation, as well as human disease state studies carried out without confirmation of test-retest reproducibility.
Collapse
Affiliation(s)
- Stuart P McCluskey
- Invicro LLC, A Konica Minolta Company, Burlington Danes Building, Imperial College London, Hammersmith Hospital, Du Cane Road, London, W12 0NN, UK.
- Psychiatric Imaging Group, MRC London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital, London, UK.
| | - Christophe Plisson
- Invicro LLC, A Konica Minolta Company, Burlington Danes Building, Imperial College London, Hammersmith Hospital, Du Cane Road, London, W12 0NN, UK
| | - Eugenii A Rabiner
- Invicro LLC, A Konica Minolta Company, Burlington Danes Building, Imperial College London, Hammersmith Hospital, Du Cane Road, London, W12 0NN, UK
| | - Oliver Howes
- Psychiatric Imaging Group, MRC London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital, London, UK
| |
Collapse
|
20
|
Poulie CBM, Jensen AA, Halberstadt AL, Kristensen JL. DARK Classics in Chemical Neuroscience: NBOMes. ACS Chem Neurosci 2019; 11:3860-3869. [PMID: 31657895 PMCID: PMC9191638 DOI: 10.1021/acschemneuro.9b00528] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
N-Benzylphenethylamines, commonly known as NBOMes, are synthetic psychedelic compounds derived from the phenethylamine class of psychedelics (2C-X compounds), which originally have been derived from the naturally occurring alkaloid mescaline. Analogously to their parent compounds and other classical psychedelics, such as psilocybin and lysergic acid diethylamide (LSD), NBOMes are believed to exert their main pharmacological effects through activation of serotonin 2A (5-HT2A) receptors. Since their introduction as New Psychoactive Substances (NPSs) in 2010, NBOMes have been widely used for recreational purposes; this has resulted in numerous cases of acute toxicity, sometimes with lethal outcomes, leading to the classification of several NBOMes as Schedule I substances in 2013. However, in addition to their recreational use, the NBOMe class has yielded several important biochemical tools, including [11C]Cimbi-36, which is now being used in positron emission tomography (PET) studies of the 5-HT2A and 5-HT2C receptors in the mammalian brain, and 25CN-NBOH, one of the most selective 5-HT2A receptor agonists developed to date. In this Review, the history, chemistry, structure-activity relationships, ADME (absorption, distribution, metabolism, and excretion) properties, and safety profiles of NBOMes will be outlined and discussed.
Collapse
|
21
|
Colom M, Vidal B, Zimmer L. Is There a Role for GPCR Agonist Radiotracers in PET Neuroimaging? Front Mol Neurosci 2019; 12:255. [PMID: 31680859 PMCID: PMC6813225 DOI: 10.3389/fnmol.2019.00255] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 10/02/2019] [Indexed: 12/30/2022] Open
Abstract
Positron emission tomography (PET) is a molecular imaging modality that enables in vivo exploration of metabolic processes and especially the pharmacology of neuroreceptors. G protein-coupled receptors (GPCRs) play an important role in numerous pathophysiologic disorders of the central nervous system. Thus, they are targets of choice in PET imaging to bring proof concept of change in density in pathological conditions or in pharmacological challenge. At present, most radiotracers are antagonist ligands. In vitro data suggest that properties differ between GPCR agonists and antagonists: antagonists bind to receptors with a single affinity, whereas agonists are characterized by two different affinities: high affinity for receptors that undergo functional coupling to G-proteins, and low affinity for those that are not coupled. In this context, agonist radiotracers may be useful tools to give functional images of GPCRs in the brain, with high sensitivity to neurotransmitter release. Here, we review all existing PET radiotracers used from animals to humans and their role for understanding the ligand-receptor paradigm of GPCR in comparison with corresponding antagonist radiotracers.
Collapse
Affiliation(s)
- Matthieu Colom
- Lyon Neuroscience Research Center, INSERM, CNRS, Université de Lyon, Lyon, France.,CERMEP, Hospices Civils de Lyon, Bron, France
| | - Benjamin Vidal
- Lyon Neuroscience Research Center, INSERM, CNRS, Université de Lyon, Lyon, France
| | - Luc Zimmer
- Lyon Neuroscience Research Center, INSERM, CNRS, Université de Lyon, Lyon, France.,CERMEP, Hospices Civils de Lyon, Bron, France.,Institut National des Sciences et Techniques Nucléaires, CEA Saclay, Gif-sur-Yvette, France
| |
Collapse
|
22
|
Yang KC, Stepanov V, Amini N, Martinsson S, Takano A, Bundgaard C, Bang-Andersen B, Sanchez C, Halldin C, Farde L, Finnema SJ. Effect of clinically relevant doses of vortioxetine and citalopram on serotonergic PET markers in the nonhuman primate brain. Neuropsychopharmacology 2019; 44:1706-1713. [PMID: 31216565 PMCID: PMC6784989 DOI: 10.1038/s41386-019-0442-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 06/04/2019] [Accepted: 06/11/2019] [Indexed: 12/18/2022]
Abstract
Vortioxetine is a multimodal antidepressant approved for treatment of major depressive disorder. Preclinical studies have demonstrated that the mechanism of action of vortioxetine might be different from selective serotonin reuptake inhibitors (SSRIs), including larger serotonin (5-HT) release and direct modulation of several 5-HT receptors. In the current positron emission tomography (PET) study, we evaluated the mechanism of action of vortioxetine by comparing its effect to the SSRI citalopram on the binding of [11C]AZ10419369 to the 5-HT1B receptor in the nonhuman primate brain. Initially, the 5-HT transporter (5-HTT) binding of vortioxetine was determined by [11C]MADAM PET measurements before and after administration of vortioxetine (0.1-3.0 mg/kg) and data were used to confirm clinically relevant dosing in subsequent PET measurements with [11C]AZ10419369. The 5-HT1B receptor binding was significantly decreased after 0.3 mg/kg of citalopram in the dorsal raphe nucleus (5%), as well as after 0.3 mg/kg of vortioxetine in six brain regions (~25%) or 1.0 mg/kg of vortioxetine in all 12 examined regions (~48%). Moreover, there was no effect of 1.0 mg/kg of vortioxetine on the binding of [11C]Cimbi-36 to the 5-HT2A receptor, which has comparable sensitivity to 5-HT release as [11C]AZ10419369 binding. In conclusion, at clinically relevant doses, vortioxetine induced larger reductions in [11C]AZ10419369 binding than citalopram. These observations suggest that vortioxetine binds to the 5-HT1B receptor at clinically relevant doses. Future studies are warranted to evaluate the role of the 5-HT1B receptor in the therapeutic effects of vortioxetine and as a potential target for the development of novel antidepressant drugs.
Collapse
Affiliation(s)
- Kai-Chun Yang
- Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden.
| | - Vladimir Stepanov
- 0000 0004 1937 0626grid.4714.6Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Nahid Amini
- 0000 0004 1937 0626grid.4714.6Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Stefan Martinsson
- 0000 0004 1937 0626grid.4714.6Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Akihiro Takano
- 0000 0004 1937 0626grid.4714.6Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | | | | | | | - Christer Halldin
- 0000 0004 1937 0626grid.4714.6Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Lars Farde
- 0000 0004 1937 0626grid.4714.6Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden ,0000 0004 1937 0626grid.4714.6Personalized Health Care and Biomarkers, AstraZeneca PET Science Center at Karolinska Institutet, Stockholm, Sweden
| | - Sjoerd J. Finnema
- 0000 0004 1937 0626grid.4714.6Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden ,0000000419368710grid.47100.32Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT USA
| |
Collapse
|
23
|
Human biodistribution and radiation dosimetry of the 5-HT 2A receptor agonist Cimbi-36 labeled with carbon-11 in two positions. EJNMMI Res 2019; 9:71. [PMID: 31367837 PMCID: PMC6669221 DOI: 10.1186/s13550-019-0527-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 06/20/2019] [Indexed: 12/17/2022] Open
Abstract
Background Cimbi-36 can be 11C-labeled to form an agonist radioligand used for positron emission tomography (PET) imaging of the 5-HT2A receptor in the brain. In its non-labeled form (25B-NBOMe), it is used as a recreational drug that can lead to severe adverse effects, in some cases, with fatal outcome. We investigated human biodistribution and radiation dosimetry of the radioligand with two different radiolabeling positions. Seven healthy volunteers underwent dynamic 120-min whole-body PET scans (injection of 581 ± 16 MBq, n = 5 for 11C-Cimbi-36; 593 ± 14 MBq, n = 2 for 11C-Cimbi-36_5). Time-integrated activity coefficients (TIACs) from time-activity curves (TACs) of selected organs were used as input into the OLINDA/EXM software to obtain dosimetry information for both 11C-labeling positions of Cimbi-36. Results The effective dose was only slightly higher for 11C-Cimbi-36 (5.5 μSv/MBq) than for 11C-Cimbi-36_5 (5.3 μSv/MBq). Standard uptake value (SUV) curves showed higher uptake of 11C-Cimbi-36 in the pancreas, small intestines, liver, kidney, gallbladder, and urinary bladder compared with 11C-Cimbi-36_5, reflecting differences in radiometabolism for the two radioligands. Variability in uptake in excretory organs for 11C-Cimbi-36 points to inter-individual differences with regard to metabolic rate and route. Surprisingly, moderate uptake was found in brown adipose tissue (BAT) in four subjects, possibly representing specific 5-HT2A/2C receptor binding. Conclusion The low effective dose of 5.5 μSv/MBq allows for the injection of up to 1.8 GBq for healthy volunteers per study (equivalent to 3 scans if injecting 600 MBq) and still stay below the international guidelines of 10 mSv, making 11C-Cimbi-36 eligible for studies involving a series of PET scans in a single subject. The biodistribution of Cimbi-36 (and its metabolites) may also help to shed light on the toxic effects of 25B-NBOMe when used in pharmacological doses in recreational settings. Electronic supplementary material The online version of this article (10.1186/s13550-019-0527-4) contains supplementary material, which is available to authorized users.
Collapse
|
24
|
Measuring endogenous changes in serotonergic neurotransmission with [ 11C]Cimbi-36 positron emission tomography in humans. Transl Psychiatry 2019; 9:134. [PMID: 30975977 PMCID: PMC6459901 DOI: 10.1038/s41398-019-0468-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 03/24/2019] [Indexed: 12/28/2022] Open
Abstract
Developing positron emission tomography (PET) radioligands for the detection of endogenous serotonin release will enable the investigation of serotonergic deficits in many neuropsychiatric disorders. The present study investigates how acute challenges that aim to increase or decrease cerebral serotonin levels affect binding of the serotonin 2A receptor (5-HT2AR) agonist radioligand [11C]Cimbi-36. In a randomized, double-blind, placebo-controlled, three-arm design, 23 healthy volunteers were PET scanned twice with [11C]Cimbi-36: at baseline and following double-blind assignment to one of three interventions (1) infusion of the selective serotonin reuptake inhibitor (SSRI) citalopram preceded by oral dosing of the 5-HT1AR antagonist pindolol, (n = 8) (2) acute tryptophan depletion (ATD) (n = 7) and (3) placebo (n = 8). Two-sample t-tests revealed no significant group differences in percent change of neocortical [11C]Cimbi-36 binding from baseline to intervention between placebo and citalopram/pindolol (p = 0.4) or between placebo and ATD (p = 0.5). Notably, there was a significantly larger within-group variation in 5-HT2AR binding after intervention with citalopram/pindolol, as compared with placebo (p = 0.007). These findings suggest that neither ATD nor a combination of citalopram and pindolol elicit acute unidirectional changes in serotonin levels sufficient to be detected with [11C]Cimbi-36 PET in neocortex. We suggest that the large interindividual variation in 5-HT2AR binding after citalopram/pindolol reflects that after an acute SSRI intervention, individuals respond substantially different in terms of their brain serotonin levels. Our observation has a potential impact for the understanding of patient responses to SSRI.
Collapse
|
25
|
Arakawa R, Farde L, Matsumoto J, Kanegawa N, Yakushev I, Yang KC, Takano A. Potential Effect of Prolonged Sevoflurane Anesthesia on the Kinetics of [ 11C]Raclopride in Non-human Primates. Mol Imaging Biol 2019; 20:183-187. [PMID: 28916921 PMCID: PMC5862918 DOI: 10.1007/s11307-017-1120-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Purpose Positron emission tomography (PET) in non-human primates (NHP) is commonly performed under anesthesia, with sevoflurane being a widely used inhaled anesthetic. PET measurement in NHP can be repeated, and a difference in radioligand kinetics has previously been observed between the first and second PET measurement on the same day using sevoflurane anesthesia. In this study, we evaluated the effect of prolonged sevoflurane anesthesia on kinetics and binding potential (BPND) of [11C]raclopride in NHP. Procedures Three cynomolgus monkeys underwent two to three PET measurements with [11C]raclopride under continuous sevoflurane anesthesia on the same day. The concentration of sevoflurane was adjusted according to the general conditions and safety parameters of the NHP. Time to peak (TTP) radioactivity in the striatum was estimated from time-activity curves (TACs). The BPND in the striatum was calculated by the simplified reference tissue model using the cerebellum as reference region. Results In each NHP, the TTP became shorter in the later PET measurements than in the first one. Across all measurements (n = 8), concentration of sevoflurane correlated with TTP (Spearman’s ρ = − 0.79, p = 0.03), but not with BPND (ρ = − 0.25, p = 0.55). Conclusions These data suggest that sevoflurane affects the shape of TACs but has no evident effect on BPND in consecutive PET measurements.
Collapse
Affiliation(s)
- Ryosuke Arakawa
- 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.,Personalized Health Care and Biomarkers, AstraZeneca PET Science Center, Karolinska Institutet, Stockholm, Sweden
| | - Junya Matsumoto
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden.,Department of Neuropsychiatry, School of Medicine, Fukushima Medical University, Fukushima, Japan
| | - Naoki Kanegawa
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Igor Yakushev
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden.,Department of Nuclear Medicine and TUM Neuroimaging Center (TUM-NIC), Technische Universität München, Munich, Germany
| | - Kai-Chun Yang
- 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
| |
Collapse
|
26
|
Prabhakaran J, DeLorenzo C, Zanderigo F, Knudsen GM, Gilling N, Pratap M, Jorgensen MJ, Daunais J, Kaplan JR, Parsey RV, Mann JJ, Kumar D. In vivo PET Imaging of [11C]CIMBI-5, a 5-HT2AR Agonist Radiotracer in Nonhuman Primates. JOURNAL OF PHARMACY & PHARMACEUTICAL SCIENCES : A PUBLICATION OF THE CANADIAN SOCIETY FOR PHARMACEUTICAL SCIENCES, SOCIETE CANADIENNE DES SCIENCES PHARMACEUTIQUES 2019; 22:352-364. [PMID: 31356761 PMCID: PMC7453972 DOI: 10.18433/jpps30329] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
PURPOSE 5-HT2AR exists in high and low affinity states. Agonist PET tracers measure binding to the active high affinity site and thus provide a functionally relevant measure of the receptor. Limited in vivo data have been reported so far for a comparison of agonist versus antagonist tracers for 5-HT2AR used as a proof of principle for measurement of high and low affinity states of this receptor. We compared the in vivo binding of [11C]CIMBI-5, a 5-HT2AR agonist, and of the antagonist [11C]M100907, in monkeys and baboons. METHODS [11C]CIMBI-5 and [11C]M100907 baseline PET scans were performed in anesthetized male baboons (n=2) and male vervet monkeys (n=2) with an ECAT EXACT HR+ and GE 64-slice PET/CT Discovery VCT scanners. Blocking studies were performed in vervet monkeys by pretreatment with MDL100907 (0.5 mg/kg, i.v.) 60 minutes prior to the scan. Regional distribution volumes and binding potentials were calculated for each ROI using the likelihood estimation in graphical analysis and Logan plot, with either plasma input function or reference region as input, and simplified reference tissue model approaches. RESULTS PET imaging of [11C]CIMBI-5 in baboons and monkeys showed the highest binding in 5-HT2AR-rich cortical regions, while the lowest binding was observed in cerebellum, consistent with the expected distribution of 5-HT2AR. Very low free fractions and rapid metabolism were observed for [11C]CIMBI-5 in baboon plasma. Binding potential values for [11C]CIMBI-5 were 25-33% lower than those for [11C]MDL100907 in the considered brain regions. CONCLUSION The lower binding potential of [11C]CIMBI-5 in comparison to [11C]MDL100907 is likely due to the preferential binding of the former to the high affinity site in vivo in contrast to the antagonist, [11C]MDL100907, which binds to both high and low affinity sites.
Collapse
Affiliation(s)
- Jaya Prabhakaran
- Department of Psychiatry, Columbia University Medical Center, New York, USA. Area of Molecular Imaging and Neuropathology, New York State Psychiatric Institute, New York, USA
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Shalgunov V, van Waarde A, Booij J, Michel MC, Dierckx RAJO, Elsinga PH. Hunting for the high-affinity state of G-protein-coupled receptors with agonist tracers: Theoretical and practical considerations for positron emission tomography imaging. Med Res Rev 2018; 39:1014-1052. [PMID: 30450619 PMCID: PMC6587759 DOI: 10.1002/med.21552] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 10/02/2018] [Accepted: 10/19/2018] [Indexed: 12/15/2022]
Abstract
The concept of the high‐affinity state postulates that a certain subset of G‐protein‐coupled receptors is primarily responsible for receptor signaling in the living brain. Assessing the abundance of this subset is thus potentially highly relevant for studies concerning the responses of neurotransmission to pharmacological or physiological stimuli and the dysregulation of neurotransmission in neurological or psychiatric disorders. The high‐affinity state is preferentially recognized by agonists in vitro. For this reason, agonist tracers have been developed as tools for the noninvasive imaging of the high‐affinity state with positron emission tomography (PET). This review provides an overview of agonist tracers that have been developed for PET imaging of the brain, and the experimental paradigms that have been developed for the estimation of the relative abundance of receptors configured in the high‐affinity state. Agonist tracers appear to be more sensitive to endogenous neurotransmitter challenge than antagonists, as was originally expected. However, other expectations regarding agonist tracers have not been fulfilled. Potential reasons for difficulties in detecting the high‐affinity state in vivo are discussed.
Collapse
Affiliation(s)
- Vladimir Shalgunov
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Aren van Waarde
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Jan Booij
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Martin C Michel
- Department of Pharmacology, Johannes Gutenberg University, Mainz, Germany
| | - Rudi A J O Dierckx
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.,Department of Nuclear Medicine, Ghent University, University Hospital, Ghent, Belgium
| | - Philip H Elsinga
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| |
Collapse
|
28
|
Zeng F, Nye JA, Voll RJ, Howell L, Goodman MM. Synthesis and Evaluation of Pyridyloxypyridyl Indole Carboxamides as Potential PET Imaging Agents for 5-HT 2C Receptors. ACS Med Chem Lett 2018. [PMID: 29541358 DOI: 10.1021/acsmedchemlett.7b00443] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Nine pyridyloxypyridyl indole carboxamides were synthesized and displayed high affinities for 5-HT2C receptors and high selectivity over 5-HT2A and 5-HT2B. Among them, 6-methyl-N-[6-[(2-methyl-3-pyridinyl)oxy]-3-pyridinyl]1H-indole-3-carboxamide (8) exhibits the highest 5-HT2C binding affinity (Ki = 1.3 nM) and high selectivity over 5-HT2A (∼1000 times) and 5-HT2B (∼140 times). [11C]8 was synthesized by palladium-catalyzed coupling reaction between pinacolboranate 16 and [11C]CH3I with an average radiochemical yield of 27 ± 4% (n = 8, decay-corrected from end of [11C]CH3I synthesis). MicroPET imaging studies in rhesus monkeys showed regional uptake of [11C]8 in the choroid plexus, whereas the bindings in all other brain regions were low. The specific binding in the choroid plexus was confirmed by administration of a blocking dose of 0.1 mg/kg of the 5-HT2C antagonist SB-242084.
Collapse
|
29
|
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.
Collapse
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
| |
Collapse
|
30
|
Hazari PP, Pandey A, Chaturvedi S, Mishra AK. New Trends and Current Status of Positron-Emission Tomography and Single-Photon-Emission Computerized Tomography Radioligands for Neuronal Serotonin Receptors and Serotonin Transporter. Bioconjug Chem 2017; 28:2647-2672. [PMID: 28767225 DOI: 10.1021/acs.bioconjchem.7b00243] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The critical role of serotonin (5-hydroxytryptamine; 5-HT) and its receptors (5-HTRs) in the pathophysiology of diverse neuropsychiatric and neurodegenerative disorders render them attractive diagnostic and therapeutic targets for brain disorders. Therefore, the in vivo assessment of binding of 5-HT receptor ligands under a multitude of physiologic and pathologic scenarios may support more-accurate identification of disease and its progression and the patient's response to therapy as well as the screening of novel therapeutic strategies. The present Review aims to focus on the current status of radioligands used for positron-emission tomography (PET) and single-photon-emission computerized tomography (SPECT) imaging of human brain serotonin receptors. We further elaborate upon and emphasize the attributes that qualify a radioligand for theranostics on the basis of its frequency of use in clinics, its benefit to risk assessment in humans, and its continuous evolution, along with the major limitations.
Collapse
Affiliation(s)
- Puja Panwar Hazari
- Division of Cyclotron and Radiopharmaceutical Sciences, Institute of Nuclear Medicine and Allied Sciences , Brig S.K. Mazumdar Road, Delhi 110054, India
| | - Ankita Pandey
- Division of Cyclotron and Radiopharmaceutical Sciences, Institute of Nuclear Medicine and Allied Sciences , Brig S.K. Mazumdar Road, Delhi 110054, India
| | - Shubhra Chaturvedi
- Division of Cyclotron and Radiopharmaceutical Sciences, Institute of Nuclear Medicine and Allied Sciences , Brig S.K. Mazumdar Road, Delhi 110054, India
| | - Anil Kumar Mishra
- Division of Cyclotron and Radiopharmaceutical Sciences, Institute of Nuclear Medicine and Allied Sciences , Brig S.K. Mazumdar Road, Delhi 110054, India
| |
Collapse
|
31
|
Schain M, Fazio P, Mrzljak L, Amini N, Al-Tawil N, Fitzer-Attas C, Bronzova J, Landwehrmeyer B, Sampaio C, Halldin C, Varrone A. Revisiting the Logan plot to account for non-negligible blood volume in brain tissue. EJNMMI Res 2017; 7:66. [PMID: 28822101 PMCID: PMC5561763 DOI: 10.1186/s13550-017-0314-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 08/08/2017] [Indexed: 11/23/2022] Open
Abstract
Background Reference tissue-based quantification of brain PET data does not typically include correction for signal originating from blood vessels, which is known to result in biased outcome measures. The bias extent depends on the amount of radioactivity in the blood vessels. In this study, we seek to revisit the well-established Logan plot and derive alternative formulations that provide estimation of distribution volume ratios (DVRs) that are corrected for the signal originating from the vasculature. Results New expressions for the Logan plot based on arterial input function and reference tissue were derived, which included explicit terms for whole blood radioactivity. The new methods were evaluated using PET data acquired using [11C]raclopride and [18F]MNI-659. The two-tissue compartment model (2TCM), with which signal originating from blood can be explicitly modeled, was used as a gold standard. DVR values obtained for [11C]raclopride using the either blood-based or reference tissue-based Logan plot were systematically underestimated compared to 2TCM, and for [18F]MNI-659, a proportionality bias was observed, i.e., the bias varied across regions. The biases disappeared when optimal blood-signal correction was used for respective tracer, although for the case of [18F]MNI-659 a small but systematic overestimation of DVR was still observed. Conclusions The new method appears to remove the bias introduced due to absence of correction for blood volume in regular graphical analysis and can be considered in clinical studies. Further studies are however required to derive a generic mapping between plasma and whole-blood radioactivity levels. Electronic supplementary material The online version of this article (doi:10.1186/s13550-017-0314-z) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Martin Schain
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden.
| | - Patrik Fazio
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | | | - Nahid Amini
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Nabil Al-Tawil
- Karolinska Trial Alliance, Karolinska University Hospital, M62, SE-141-86, Stockholm, Sweden
| | | | | | | | | | - Christer Halldin
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Andrea Varrone
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| |
Collapse
|
32
|
Heurling K, Leuzy A, Jonasson M, Frick A, Zimmer ER, Nordberg A, Lubberink M. Quantitative positron emission tomography in brain research. Brain Res 2017; 1670:220-234. [PMID: 28652218 DOI: 10.1016/j.brainres.2017.06.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 06/19/2017] [Accepted: 06/20/2017] [Indexed: 12/21/2022]
Abstract
The application of positron emission tomography (PET) in brain research has increased substantially during the past 20years, and is still growing. PET provides a unique insight into physiological and pathological processes in vivo. In this article we introduce the fundamentals of PET, and the methods available for acquiring quantitative estimates of the parameters of interest. A short introduction to different areas of application is also given, including basic research of brain function and in neurology, psychiatry, drug receptor occupancy studies, and its application in diagnostics of neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease. Our aim is to inform the unfamiliar reader of the underlying basics and potential applications of PET, hoping to inspire the reader into considering how the technique could be of benefit for his or her own research.
Collapse
Affiliation(s)
- Kerstin Heurling
- Wallenberg Centre for Molecular and Translational Medicine and the Department of Psychiatry and Neurochemistry, University of Gothenburg, Sweden; Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.
| | - Antoine Leuzy
- Department Neurobiology, Care Sciences and Society, Division of Translational Alzheimer Neurobiology, Karolinska Institutet, Stockholm, Sweden
| | - My Jonasson
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden; Medical Physics, Uppsala University Hospital, Uppsala, Sweden
| | - Andreas Frick
- Department of Psychology, Uppsala University, Uppsala, Sweden; Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Eduardo R Zimmer
- Department of Biochemistry, Federal University of Rio Grande do Sul, Porto Alegre, Brazil; Brain Institute of Rio Grande do Sul (BraIns), Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Agneta Nordberg
- Department Neurobiology, Care Sciences and Society, Division of Translational Alzheimer Neurobiology, Karolinska Institutet, Stockholm, Sweden; Department of Geriatric Medicine, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Mark Lubberink
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden; Medical Physics, Uppsala University Hospital, Uppsala, Sweden
| |
Collapse
|
33
|
Yang KC, Stepanov V, Martinsson S, Ettrup A, Takano A, Knudsen GM, Halldin C, Farde L, Finnema SJ. Fenfluramine Reduces [11C]Cimbi-36 Binding to the 5-HT2A Receptor in the Nonhuman Primate Brain. Int J Neuropsychopharmacol 2017; 20:683-691. [PMID: 28911007 PMCID: PMC5581490 DOI: 10.1093/ijnp/pyx051] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 06/18/2017] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND [11C]Cimbi-36 is a serotonin 2A receptor agonist positron emission tomography radioligand that has recently been examined in humans. The binding of agonist radioligand is expected to be more sensitive to endogenous neurotransmitter concentrations than antagonist radioligands. In the current study, we compared the effect of serotonin releaser fenfluramine on the binding of [11C]Cimbi-36, [11C]MDL 100907 (a serotonin 2A receptor antagonist radioligand), and [11C]AZ10419369 (a serotonin 1B receptor partial agonist radioligand with established serotonin sensitivity) in the monkey brain. METHODS Eighteen positron emission tomography measurements, 6 for each radioligand, were performed in 3 rhesus monkeys before or after administration of 5.0 mg/kg fenfluramine. Binding potential values were determined with the simplified reference tissue model using cerebellum as the reference region. RESULTS Fenfluramine significantly decreased [11C]Cimbi-36 (26-62%) and [11C]AZ10419369 (35-58%) binding potential values in most regions (P < 0.05). Fenfluramine-induced decreases in [11C]MDL 100907 binding potential were 8% to 30% and statistically significant in 3 regions. Decreases in [11C]Cimbi-36 binding potential were larger than for [11C]AZ10419369 in neocortical and limbic regions (~35%) but smaller in striatum and thalamus (~40%). Decreases in [11C]Cimbi-36 binding potential were 0.9 to 2.8 times larger than for [11C]MDL 100907, and the fraction of serotonin 2A receptor in the high-affinity state was estimated as 54% in the neocortex. CONCLUSIONS The serotonin sensitivity of serotonin 2A receptor agonist radioligand [11C]Cimbi-36 was higher than for antagonist radioligand [11C]MDL 100907. The serotonin sensitivity of [11C]Cimbi-36 was similar to [11C]AZ10419369, which is one of the most sensitive radioligands. [11C]Cimbi-36 is a promising radioligand to examine serotonin release in the primate brain.
Collapse
Affiliation(s)
- Kai-Chun Yang
- Karolinska Institutet and Stockholm County Council, Department of Clinical Neuroscience, Center for Psychiatric Research, Stockholm, Sweden (Drs Yang and Stepanov, Mr Martinsson, and Drs Takano, Halldin, Farde, and Finnema); Rigshospitalet, Center for Integrated Molecular Brain Imaging, Copenhagen, Denmark and University of Copenhagen, Faculty of Health and Medicine Sciences, Copenhagen, Denmark (Drs Ettrup and Knudsen); AstraZeneca, PET Science Center at Karolinska Institutet, Personalized Health Care and Biomarkers, Stockholm, Sweden (Dr Farde).,Correspondence: Kai-Chun Yang, MD, Karolinska Institutet and Stockholm County Council, Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska University Hospital, Building R5:02, SE-171 76 Stockholm, Sweden ()
| | - Vladimir Stepanov
- Karolinska Institutet and Stockholm County Council, Department of Clinical Neuroscience, Center for Psychiatric Research, Stockholm, Sweden (Drs Yang and Stepanov, Mr Martinsson, and Drs Takano, Halldin, Farde, and Finnema); Rigshospitalet, Center for Integrated Molecular Brain Imaging, Copenhagen, Denmark and University of Copenhagen, Faculty of Health and Medicine Sciences, Copenhagen, Denmark (Drs Ettrup and Knudsen); AstraZeneca, PET Science Center at Karolinska Institutet, Personalized Health Care and Biomarkers, Stockholm, Sweden (Dr Farde)
| | - Stefan Martinsson
- Karolinska Institutet and Stockholm County Council, Department of Clinical Neuroscience, Center for Psychiatric Research, Stockholm, Sweden (Drs Yang and Stepanov, Mr Martinsson, and Drs Takano, Halldin, Farde, and Finnema); Rigshospitalet, Center for Integrated Molecular Brain Imaging, Copenhagen, Denmark and University of Copenhagen, Faculty of Health and Medicine Sciences, Copenhagen, Denmark (Drs Ettrup and Knudsen); AstraZeneca, PET Science Center at Karolinska Institutet, Personalized Health Care and Biomarkers, Stockholm, Sweden (Dr Farde)
| | - Anders Ettrup
- Karolinska Institutet and Stockholm County Council, Department of Clinical Neuroscience, Center for Psychiatric Research, Stockholm, Sweden (Drs Yang and Stepanov, Mr Martinsson, and Drs Takano, Halldin, Farde, and Finnema); Rigshospitalet, Center for Integrated Molecular Brain Imaging, Copenhagen, Denmark and University of Copenhagen, Faculty of Health and Medicine Sciences, Copenhagen, Denmark (Drs Ettrup and Knudsen); AstraZeneca, PET Science Center at Karolinska Institutet, Personalized Health Care and Biomarkers, Stockholm, Sweden (Dr Farde)
| | - Akihiro Takano
- Karolinska Institutet and Stockholm County Council, Department of Clinical Neuroscience, Center for Psychiatric Research, Stockholm, Sweden (Drs Yang and Stepanov, Mr Martinsson, and Drs Takano, Halldin, Farde, and Finnema); Rigshospitalet, Center for Integrated Molecular Brain Imaging, Copenhagen, Denmark and University of Copenhagen, Faculty of Health and Medicine Sciences, Copenhagen, Denmark (Drs Ettrup and Knudsen); AstraZeneca, PET Science Center at Karolinska Institutet, Personalized Health Care and Biomarkers, Stockholm, Sweden (Dr Farde)
| | - Gitte M Knudsen
- Karolinska Institutet and Stockholm County Council, Department of Clinical Neuroscience, Center for Psychiatric Research, Stockholm, Sweden (Drs Yang and Stepanov, Mr Martinsson, and Drs Takano, Halldin, Farde, and Finnema); Rigshospitalet, Center for Integrated Molecular Brain Imaging, Copenhagen, Denmark and University of Copenhagen, Faculty of Health and Medicine Sciences, Copenhagen, Denmark (Drs Ettrup and Knudsen); AstraZeneca, PET Science Center at Karolinska Institutet, Personalized Health Care and Biomarkers, Stockholm, Sweden (Dr Farde)
| | - Christer Halldin
- Karolinska Institutet and Stockholm County Council, Department of Clinical Neuroscience, Center for Psychiatric Research, Stockholm, Sweden (Drs Yang and Stepanov, Mr Martinsson, and Drs Takano, Halldin, Farde, and Finnema); Rigshospitalet, Center for Integrated Molecular Brain Imaging, Copenhagen, Denmark and University of Copenhagen, Faculty of Health and Medicine Sciences, Copenhagen, Denmark (Drs Ettrup and Knudsen); AstraZeneca, PET Science Center at Karolinska Institutet, Personalized Health Care and Biomarkers, Stockholm, Sweden (Dr Farde)
| | - Lars Farde
- Karolinska Institutet and Stockholm County Council, Department of Clinical Neuroscience, Center for Psychiatric Research, Stockholm, Sweden (Drs Yang and Stepanov, Mr Martinsson, and Drs Takano, Halldin, Farde, and Finnema); Rigshospitalet, Center for Integrated Molecular Brain Imaging, Copenhagen, Denmark and University of Copenhagen, Faculty of Health and Medicine Sciences, Copenhagen, Denmark (Drs Ettrup and Knudsen); AstraZeneca, PET Science Center at Karolinska Institutet, Personalized Health Care and Biomarkers, Stockholm, Sweden (Dr Farde)
| | - Sjoerd J Finnema
- Karolinska Institutet and Stockholm County Council, Department of Clinical Neuroscience, Center for Psychiatric Research, Stockholm, Sweden (Drs Yang and Stepanov, Mr Martinsson, and Drs Takano, Halldin, Farde, and Finnema); Rigshospitalet, Center for Integrated Molecular Brain Imaging, Copenhagen, Denmark and University of Copenhagen, Faculty of Health and Medicine Sciences, Copenhagen, Denmark (Drs Ettrup and Knudsen); AstraZeneca, PET Science Center at Karolinska Institutet, Personalized Health Care and Biomarkers, Stockholm, Sweden (Dr Farde)
| |
Collapse
|
34
|
Pasin D, Cawley A, Bidny S, Fu S. Characterization of hallucinogenic phenethylamines using high-resolution mass spectrometry for non-targeted screening purposes. Drug Test Anal 2017; 9:1620-1629. [DOI: 10.1002/dta.2171] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 01/22/2017] [Accepted: 01/23/2017] [Indexed: 02/02/2023]
Affiliation(s)
- Daniel Pasin
- Centre for Forensic Science; University of Technology Sydney; Broadway NSW 2007 Australia
| | - Adam Cawley
- Australian Racing Forensic Laboratory; Racing NSW Sydney NSW 2000 Australia
| | - Sergei Bidny
- Forensic Toxicology Laboratory; NSW Forensic and Analytical Science Service; Lidcombe NSW 2141 Australia
| | - Shanlin Fu
- Centre for Forensic Science; University of Technology Sydney; Broadway NSW 2007 Australia
| |
Collapse
|
35
|
Schain M, Zanderigo F, Mann J, Ogden R. Estimation of the binding potential BPND without a reference region or blood samples for brain PET studies. Neuroimage 2017; 146:121-131. [PMID: 27856316 DOI: 10.1016/j.neuroimage.2016.11.035] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 11/13/2016] [Indexed: 02/02/2023] Open
|
36
|
Prabhakaran J, Solingapuram Sai KK, Zanderigo F, Rubin-Falcone H, Jorgensen MJ, Kaplan JR, Tooke KI, Mintz A, Mann JJ, Kumar JSD. In vivo evaluation of [ 18F]FECIMBI-36, an agonist 5-HT 2A/2C receptor PET radioligand in nonhuman primate. Bioorg Med Chem Lett 2017; 27:21-23. [PMID: 27889455 PMCID: PMC5348621 DOI: 10.1016/j.bmcl.2016.11.043] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 11/14/2016] [Accepted: 11/15/2016] [Indexed: 11/20/2022]
Abstract
We recently reported the radiosynthesis and in vitro evaluation of [18F]-2-(4-bromo-2,5-dimethoxyphenyl)-N-(2-(2-fluoroethoxy)benzyl)ethanamine, ([18F]FECIMBI-36) or ([18F]1), an agonist radioligand for 5HT2A/2C receptors in postmortem samples of human brain. Herein we describe the in vivo evaluation of [18F]FECIMBI-36 in vervet/African green monkeys by PET imaging. PET images show that [18F]FECIMBI-36 penetrates the blood-brain barrier and a low retention of radioactivity is observed in monkey brain. Although the time activity curves indicate a somehow heterogeneous distribution of the radioligand in the brain, the low level of [18F]FECIMBI-36 in brain may limit the use of this tracer for quantification of 5-HT2A/2C receptors by PET.
Collapse
Affiliation(s)
- Jaya Prabhakaran
- Department of Psychiatry, Columbia University Medical Center, New York, USA; Molecular Imaging and Neuropathology Division, New York State Psychiatric Institute, New York, USA
| | | | - Francesca Zanderigo
- Department of Psychiatry, Columbia University Medical Center, New York, USA; Molecular Imaging and Neuropathology Division, New York State Psychiatric Institute, New York, USA
| | | | - Matthew J Jorgensen
- Department of Pathology, Section on Comparative Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Jay R Kaplan
- Department of Pathology, Section on Comparative Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Katharine I Tooke
- Department of Psychiatry, Columbia University Medical Center, New York, USA
| | - Akiva Mintz
- Department of Radiology, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - J John Mann
- Department of Psychiatry, Columbia University Medical Center, New York, USA; Molecular Imaging and Neuropathology Division, New York State Psychiatric Institute, New York, USA
| | - J S Dileep Kumar
- Molecular Imaging and Neuropathology Division, New York State Psychiatric Institute, New York, USA.
| |
Collapse
|
37
|
Yang KC, Stepanov V, Amini N, Martinsson S, Takano A, Nielsen J, Bundgaard C, Bang-Andersen B, Grimwood S, Halldin C, Farde L, Finnema SJ. Characterization of [ 11C]Lu AE92686 as a PET radioligand for phosphodiesterase 10A in the nonhuman primate brain. Eur J Nucl Med Mol Imaging 2016; 44:308-320. [PMID: 27817159 PMCID: PMC5215309 DOI: 10.1007/s00259-016-3544-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 10/03/2016] [Indexed: 11/28/2022]
Abstract
Purpose [11C]Lu AE92686 is a positron emission tomography (PET) radioligand that has recently been validated for examining phosphodiesterase 10A (PDE10A) in the human striatum. [11C]Lu AE92686 has high affinity for PDE10A (IC50 = 0.39 nM) and may also be suitable for examination of the substantia nigra, a region with low density of PDE10A. Here, we report characterization of regional [11C]Lu AE92686 binding to PDE10A in the nonhuman primate (NHP) brain. Methods A total of 11 PET measurements, seven baseline and four following pretreatment with unlabeled Lu AE92686 or the structurally unrelated PDE10A inhibitor MP-10, were performed in five NHPs using a high resolution research tomograph (HRRT). [11C]Lu AE92686 binding was quantified using a radiometabolite-corrected arterial input function and compartmental and graphical modeling approaches. Results Regional time-activity curves were best described with the two-tissue compartment model (2TCM). However, the distribution volume (VT) values for all regions were obtained by the Logan plot analysis, as reliable cerebellar VT values could not be derived by the 2TCM. For cerebellum, a proposed reference region, VT values increased by ∼30 % with increasing PET measurement duration from 63 to 123 min, while VT values in target regions remained stable. Both pretreatment drugs significantly decreased [11C]Lu AE92686 binding in target regions, while no significant effect on cerebellum was observed. Binding potential (BPND) values, derived with the simplified reference tissue model (SRTM), were 13–17 in putamen and 3–5 in substantia nigra and correlated well to values from the Logan plot analysis. Conclusions The method proposed for quantification of [11C]Lu AE92686 binding in applied studies in NHP is based on 63 min PET data and SRTM with cerebellum as a reference region. The study supports that [11C]Lu AE92686 can be used for PET examinations of PDE10A binding also in substantia nigra. Electronic supplementary material The online version of this article (doi:10.1007/s00259-016-3544-9) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Kai-Chun Yang
- Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.
| | - Vladimir Stepanov
- Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Nahid Amini
- Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Stefan Martinsson
- Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Akihiro Takano
- Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Jacob Nielsen
- Synaptic Transmission, H. Lundbeck A/S, Valby, Denmark
| | | | | | - Sarah Grimwood
- Neuroscience and Pain Research Unit, Pfizer Inc., Cambridge, MA, USA
| | - Christer Halldin
- Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Lars Farde
- Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.,Personalized Health Care and Biomarkers, AstraZeneca PET Science Center at Karolinska Institutet, Stockholm, Sweden
| | - Sjoerd J Finnema
- Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.,Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT, USA
| |
Collapse
|
38
|
Synthesis and evaluation of 18F-labeled 5-HT2A receptor agonists as PET ligands. Nucl Med Biol 2016; 43:455-62. [DOI: 10.1016/j.nucmedbio.2016.02.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 02/15/2016] [Accepted: 02/17/2016] [Indexed: 11/23/2022]
|
39
|
Abstract
Psychedelics (serotonergic hallucinogens) are powerful psychoactive substances that alter perception and mood and affect numerous cognitive processes. They are generally considered physiologically safe and do not lead to dependence or addiction. Their origin predates written history, and they were employed by early cultures in many sociocultural and ritual contexts. After the virtually contemporaneous discovery of (5R,8R)-(+)-lysergic acid-N,N-diethylamide (LSD)-25 and the identification of serotonin in the brain, early research focused intensively on the possibility that LSD and other psychedelics had a serotonergic basis for their action. Today there is a consensus that psychedelics are agonists or partial agonists at brain serotonin 5-hydroxytryptamine 2A receptors, with particular importance on those expressed on apical dendrites of neocortical pyramidal cells in layer V. Several useful rodent models have been developed over the years to help unravel the neurochemical correlates of serotonin 5-hydroxytryptamine 2A receptor activation in the brain, and a variety of imaging techniques have been employed to identify key brain areas that are directly affected by psychedelics. Recent and exciting developments in the field have occurred in clinical research, where several double-blind placebo-controlled phase 2 studies of psilocybin-assisted psychotherapy in patients with cancer-related psychosocial distress have demonstrated unprecedented positive relief of anxiety and depression. Two small pilot studies of psilocybin-assisted psychotherapy also have shown positive benefit in treating both alcohol and nicotine addiction. Recently, blood oxygen level-dependent functional magnetic resonance imaging and magnetoencephalography have been employed for in vivo brain imaging in humans after administration of a psychedelic, and results indicate that intravenously administered psilocybin and LSD produce decreases in oscillatory power in areas of the brain's default mode network.
Collapse
Affiliation(s)
- David E Nichols
- Eschelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina
| |
Collapse
|
40
|
Ettrup A, Svarer C, McMahon B, da Cunha-Bang S, Lehel S, Møller K, Dyssegaard A, Ganz M, Beliveau V, Jørgensen LM, Gillings N, Knudsen GM. Serotonin 2A receptor agonist binding in the human brain with [(11)C]Cimbi-36: Test-retest reproducibility and head-to-head comparison with the antagonist [(18)F]altanserin. Neuroimage 2016; 130:167-174. [PMID: 26876490 DOI: 10.1016/j.neuroimage.2016.02.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 01/27/2016] [Accepted: 02/02/2016] [Indexed: 11/29/2022] Open
Abstract
INTRODUCTION [(11)C]Cimbi-36 is a recently developed serotonin 2A (5-HT2A) receptor agonist positron emission tomography (PET) radioligand that has been successfully applied for human neuroimaging. Here, we investigate the test-retest variability of cerebral [(11)C]Cimbi-36 PET and compare [(11)C]Cimbi-36 and the 5-HT2A receptor antagonist [(18)F]altanserin. METHODS Sixteen healthy volunteers (mean age 23.9 ± 6.4years, 6 males) were scanned twice with a high resolution research tomography PET scanner. All subjects were scanned after a bolus of [(11)C]Cimbi-36; eight were scanned twice to determine test-retest variability in [(11)C]Cimbi-36 binding measures, and another eight were scanned after a bolus plus constant infusion with [(18)F]altanserin. Regional differences in the brain distribution of [(11)C]Cimbi-36 and [(18)F]altanserin were assessed with a correlation of regional binding measures and with voxel-based analysis. RESULTS Test-retest variability of [(11)C]Cimbi-36 non-displaceable binding potential (BPND) was consistently <5% in high-binding regions and lower for reference tissue models as compared to a 2-tissue compartment model. We found a highly significant correlation between regional BPNDs measured with [(11)C]Cimbi-36 and [(18)F]altanserin (mean Pearson's r: 0.95 ± 0.04) suggesting similar cortical binding of the radioligands. Relatively higher binding with [(11)C]Cimbi-36 as compared to [(18)F]altanserin was found in the choroid plexus and hippocampus in the human brain. CONCLUSIONS Excellent test-retest reproducibility highlights the potential of [(11)C]Cimbi-36 for PET imaging of 5-HT2A receptor agonist binding in vivo. Our data suggest that Cimbi-36 and altanserin both bind to 5-HT2A receptors, but in regions with high 5-HT2C receptor density, choroid plexus and hippocampus, the [(11)C]Cimbi-36 binding likely represents binding to both 5-HT2A and 5-HT2C receptors.
Collapse
Affiliation(s)
- Anders Ettrup
- Neurobiology Research Unit, Center for Integrated Molecular Brain Imaging (Cimbi), Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Claus Svarer
- Neurobiology Research Unit, Center for Integrated Molecular Brain Imaging (Cimbi), Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Brenda McMahon
- Neurobiology Research Unit, Center for Integrated Molecular Brain Imaging (Cimbi), Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Sofi da Cunha-Bang
- Neurobiology Research Unit, Center for Integrated Molecular Brain Imaging (Cimbi), Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Szabolcs Lehel
- Department of Clinical Physiology, Nuclear Medicine and PET, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Kirsten Møller
- Department of Neuroanaesthesiology, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Agnete Dyssegaard
- Neurobiology Research Unit, Center for Integrated Molecular Brain Imaging (Cimbi), Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Melanie Ganz
- Neurobiology Research Unit, Center for Integrated Molecular Brain Imaging (Cimbi), Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Vincent Beliveau
- Neurobiology Research Unit, Center for Integrated Molecular Brain Imaging (Cimbi), Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Louise Møller Jørgensen
- Neurobiology Research Unit, Center for Integrated Molecular Brain Imaging (Cimbi), Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Nic Gillings
- Department of Clinical Physiology, Nuclear Medicine and PET, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Gitte Moos Knudsen
- Neurobiology Research Unit, Center for Integrated Molecular Brain Imaging (Cimbi), Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
| |
Collapse
|
41
|
Leth-Petersen S, Gabel-Jensen C, Gillings N, Lehel S, Hansen HD, Knudsen GM, Kristensen JL. Metabolic Fate of Hallucinogenic NBOMes. Chem Res Toxicol 2015; 29:96-100. [DOI: 10.1021/acs.chemrestox.5b00450] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sebastian Leth-Petersen
- Department of Drug Design and Pharmacology and ‡Department of Pharmacy, University of Copenhagen, DK-2100 Copenhagen, Denmark
- PET and Cyclotron Unit and ∥Neurobiology Research
Unit and Center for Integrated
Molecular Brain Imaging, Copenhagen University Hospital, DK-2100 Copenhagen, Denmark
| | - Charlotte Gabel-Jensen
- Department of Drug Design and Pharmacology and ‡Department of Pharmacy, University of Copenhagen, DK-2100 Copenhagen, Denmark
- PET and Cyclotron Unit and ∥Neurobiology Research
Unit and Center for Integrated
Molecular Brain Imaging, Copenhagen University Hospital, DK-2100 Copenhagen, Denmark
| | - Nic Gillings
- Department of Drug Design and Pharmacology and ‡Department of Pharmacy, University of Copenhagen, DK-2100 Copenhagen, Denmark
- PET and Cyclotron Unit and ∥Neurobiology Research
Unit and Center for Integrated
Molecular Brain Imaging, Copenhagen University Hospital, DK-2100 Copenhagen, Denmark
| | - Szabolzs Lehel
- Department of Drug Design and Pharmacology and ‡Department of Pharmacy, University of Copenhagen, DK-2100 Copenhagen, Denmark
- PET and Cyclotron Unit and ∥Neurobiology Research
Unit and Center for Integrated
Molecular Brain Imaging, Copenhagen University Hospital, DK-2100 Copenhagen, Denmark
| | - Hanne D. Hansen
- Department of Drug Design and Pharmacology and ‡Department of Pharmacy, University of Copenhagen, DK-2100 Copenhagen, Denmark
- PET and Cyclotron Unit and ∥Neurobiology Research
Unit and Center for Integrated
Molecular Brain Imaging, Copenhagen University Hospital, DK-2100 Copenhagen, Denmark
| | - Gitte M. Knudsen
- Department of Drug Design and Pharmacology and ‡Department of Pharmacy, University of Copenhagen, DK-2100 Copenhagen, Denmark
- PET and Cyclotron Unit and ∥Neurobiology Research
Unit and Center for Integrated
Molecular Brain Imaging, Copenhagen University Hospital, DK-2100 Copenhagen, Denmark
| | - Jesper L. Kristensen
- Department of Drug Design and Pharmacology and ‡Department of Pharmacy, University of Copenhagen, DK-2100 Copenhagen, Denmark
- PET and Cyclotron Unit and ∥Neurobiology Research
Unit and Center for Integrated
Molecular Brain Imaging, Copenhagen University Hospital, DK-2100 Copenhagen, Denmark
| |
Collapse
|
42
|
Gee P, Schep LJ, Jensen BP, Moore G, Barrington S. Case series: toxicity from 25B-NBOMe – a cluster of N-bomb cases. Clin Toxicol (Phila) 2015; 54:141-6. [DOI: 10.3109/15563650.2015.1115056] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Paul Gee
- Emergency Physician, Christchurch Hospital, Christchurch, New Zealand
| | - Leo J. Schep
- Toxicologist National Poisons Centre, University of Otago, Dunedin, New Zealand
| | - Berit P. Jensen
- Scientific Officer, Toxicology, Specialist Cluster, Canterbury Health Laboratories, Christchurch, New Zealand
| | - Grant Moore
- Toxicology Section Head, Specialist Cluster, Canterbury Health Laboratories, Christchurch, New Zealand
| | - Stuart Barrington
- Emergency Physician, Christchurch Hospital, Christchurch, New Zealand
| |
Collapse
|
43
|
Di Giovanni G, De Deurwaerdère P. New therapeutic opportunities for 5-HT2C receptor ligands in neuropsychiatric disorders. Pharmacol Ther 2015; 157:125-62. [PMID: 26617215 DOI: 10.1016/j.pharmthera.2015.11.009] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The 5-HT2C receptor (R) displays a widespread distribution in the CNS and is involved in the action of 5-HT in all brain areas. Knowledge of its functional role in the CNS pathophysiology has been impaired for many years due to the lack of drugs capable of discriminating among 5-HT2R subtypes, and to a lesser extent to the 5-HT1B, 5-HT5, 5-HT6 and 5-HT7Rs. The situation has changed since the mid-90s due to the increased availability of new and selective synthesized compounds, the creation of 5-HT2C knock out mice, and the progress made in molecular biology. Many pharmacological classes of drugs including antipsychotics, antidepressants and anxiolytics display affinities toward 5-HT2CRs and new 5-HT2C ligands have been developed for various neuropsychiatric disorders. The 5-HT2CR is presumed to mediate tonic/constitutive and phasic controls on the activity of different central neurobiological networks. Preclinical data illustrate this complexity to a point that pharmaceutical companies developed either agonists or antagonists for the same disease. In order to better comprehend this complexity, this review will briefly describe the molecular pharmacology of 5-HT2CRs, as well as their cellular impacts in general, before addressing its central distribution in the mammalian brain. Thereafter, we review the preclinical efficacy of 5-HT2C ligands in numerous behavioral tests modeling human diseases, highlighting the multiple and competing actions of the 5-HT2CRs in neurobiological networks and monoaminergic systems. Notably, we will focus this evidence in the context of the physiopathology of psychiatric and neurological disorders including Parkinson's disease, levodopa-induced dyskinesia, and epilepsy.
Collapse
Affiliation(s)
- Giuseppe Di Giovanni
- Department of Physiology & Biochemistry, Faculty of Medicine and Surgery, University of Malta; Neuroscience Division, School of Biosciences, Cardiff University, Cardiff, UK.
| | - Philippe De Deurwaerdère
- Centre National de la Recherche Scientifique (Unité Mixte de Recherche 5293) 33076 Bordeaux Cedex, France.
| |
Collapse
|
44
|
Prabhakaran J, Underwood MD, Kumar JSD, Simpson NR, Kassir SA, Bakalian MJ, Mann JJ, Arango V. Synthesis and in vitro evaluation of [18F]FECIMBI-36: A potential agonist PET ligand for 5-HT2A/2C receptors. Bioorg Med Chem Lett 2015; 25:3933-6. [PMID: 26253634 DOI: 10.1016/j.bmcl.2015.07.034] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2015] [Revised: 07/12/2015] [Accepted: 07/15/2015] [Indexed: 11/19/2022]
Abstract
Radiosynthesis and in vitro evaluation of [(18)F]-2-(4-bromo-2,5-dimethoxyphenyl)-N-(2-(2-fluoroethoxy)benzyl)ethanamine, ([(18)F]FECIMBI-36) or ([(18)F]1), a potential agonist PET imaging agent for 5-HT2A/2C receptors is described. Syntheses of reference standard 1 and the corresponding des-fluoroethyl radiolabeling precursor (2) were achieved with 75% and 65% yields, respectively. In vitro pharmacology assay of FECIMBI-36 by [(3)H]-ketanserin competition binding assay obtained from NIMH-PDSP showed high affinities to 5-HT2AR (Ki = 1nM) and 5-HT2CR (Ki=1.7 nM). Radiolabeling of FECIMBI-36 was achieved from the boc-protected precursor 2 using [(18)F]-fluoroethyltosylate in presence of Cs2CO3 in DMSO followed by removal of the protective group. [(18)F]1 was isolated using RP-HPLC in 25 ± 5% yield, purity > 95% and specific activity 1-2Ci/μmol (N = 6). In vitro autoradiography studies demonstrate that [(18)F]1 selectively label 5-HT2A and 5-HT2C receptors in slide-mounted sections of postmortem human brain using phosphor imaging. Our results indicate the potential of [(18)F]1 for imaging 5-HT2A/2C receptors in the high affinity state in vivo using PET imaging.
Collapse
Affiliation(s)
- Jaya Prabhakaran
- Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, NY, USA.
| | - Mark D Underwood
- Molecular Imaging and Neuropathology Division, New York State Psychiatric Institute, New York, NY, USA; Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, NY, USA
| | - J S Dileep Kumar
- Molecular Imaging and Neuropathology Division, New York State Psychiatric Institute, New York, NY, USA
| | - Norman R Simpson
- Molecular Imaging and Neuropathology Division, New York State Psychiatric Institute, New York, NY, USA
| | - Suham A Kassir
- Molecular Imaging and Neuropathology Division, New York State Psychiatric Institute, New York, NY, USA
| | - Mihran J Bakalian
- Molecular Imaging and Neuropathology Division, New York State Psychiatric Institute, New York, NY, USA
| | - J John Mann
- Molecular Imaging and Neuropathology Division, New York State Psychiatric Institute, New York, NY, USA; Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, NY, USA
| | - Victoria Arango
- Molecular Imaging and Neuropathology Division, New York State Psychiatric Institute, New York, NY, USA; Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, NY, USA
| |
Collapse
|
45
|
Hansen M, Jacobsen SE, Plunkett S, Liebscher GE, McCorvy JD, Bräuner-Osborne H, Kristensen JL. Synthesis and pharmacological evaluation of N-benzyl substituted 4-bromo-2,5-dimethoxyphenethylamines as 5-HT2A/2C partial agonists. Bioorg Med Chem 2015; 23:3933-7. [DOI: 10.1016/j.bmc.2014.12.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 12/06/2014] [Accepted: 12/10/2014] [Indexed: 12/20/2022]
|
46
|
Gravel P, Reader AJ. Direct 4D PET MLEM reconstruction of parametric images using the simplified reference tissue model with the basis function method for [11C]raclopride. Phys Med Biol 2015; 60:4533-49. [DOI: 10.1088/0031-9155/60/11/4533] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|
47
|
Fazio P, Svenningsson P, Forsberg A, Jönsson EG, Amini N, Nakao R, Nag S, Halldin C, Farde L, Varrone A. Quantitative Analysis of 18F-(E)-N-(3-Iodoprop-2-Enyl)-2β-Carbofluoroethoxy-3β-(4′-Methyl-Phenyl) Nortropane Binding to the Dopamine Transporter in Parkinson Disease. J Nucl Med 2015; 56:714-20. [DOI: 10.2967/jnumed.114.152421] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Accepted: 02/25/2015] [Indexed: 01/27/2023] Open
|
48
|
Visser AK, Ettrup A, Klein AB, van Waarde A, Bosker FJ, Meerlo P, Knudsen GM, de Boer SF. Similar serotonin-2A receptor binding in rats with different coping styles or levels of aggression. Synapse 2015; 69:226-32. [DOI: 10.1002/syn.21810] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 02/03/2015] [Accepted: 02/07/2015] [Indexed: 11/07/2022]
Affiliation(s)
- Anniek K.D. Visser
- Department of Nuclear Medicine and Molecular Imaging; University of Groningen, University Medical Center Groningen; Groningen The Netherlands
| | - Anders Ettrup
- Neurobiology Research Unit, Rigshospitalet and University of Copenhagen; Copenhagen Denmark
| | - Anders B. Klein
- Neurobiology Research Unit, Rigshospitalet and University of Copenhagen; Copenhagen Denmark
| | - Aren van Waarde
- Department of Nuclear Medicine and Molecular Imaging; University of Groningen, University Medical Center Groningen; Groningen The Netherlands
| | - Fokko J. Bosker
- Department of General Psychiatry, University Center of Psychiatry, University of Groningen, University Medical Center Groningen; Groningen The Netherlands
| | - Peter Meerlo
- Department of Behavioral Physiology; Center for Behavior and Neurosciences, University of Groningen; Groningen The Netherlands
| | - Gitte M. Knudsen
- Neurobiology Research Unit, Rigshospitalet and University of Copenhagen; Copenhagen Denmark
| | - Sietse F. de Boer
- Department of Behavioral Physiology; Center for Behavior and Neurosciences, University of Groningen; Groningen The Netherlands
| |
Collapse
|
49
|
Finnema SJ, Scheinin M, Shahid M, Lehto J, Borroni E, Bang-Andersen B, Sallinen J, Wong E, Farde L, Halldin C, Grimwood S. Application of cross-species PET imaging to assess neurotransmitter release in brain. Psychopharmacology (Berl) 2015; 232:4129-57. [PMID: 25921033 PMCID: PMC4600473 DOI: 10.1007/s00213-015-3938-6] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 04/09/2015] [Indexed: 01/03/2023]
Abstract
RATIONALE This review attempts to summarize the current status in relation to the use of positron emission tomography (PET) imaging in the assessment of synaptic concentrations of endogenous mediators in the living brain. OBJECTIVES Although PET radioligands are now available for more than 40 CNS targets, at the initiation of the Innovative Medicines Initiative (IMI) "Novel Methods leading to New Medications in Depression and Schizophrenia" (NEWMEDS) in 2009, PET radioligands sensitive to an endogenous neurotransmitter were only validated for dopamine. NEWMEDS work-package 5, "Cross-species and neurochemical imaging (PET) methods for drug discovery", commenced with a focus on developing methods enabling assessment of changes in extracellular concentrations of serotonin and noradrenaline in the brain. RESULTS Sharing the workload across institutions, we utilized in vitro techniques with cells and tissues, in vivo receptor binding and microdialysis techniques in rodents, and in vivo PET imaging in non-human primates and humans. Here, we discuss these efforts and review other recently published reports on the use of radioligands to assess changes in endogenous levels of dopamine, serotonin, noradrenaline, γ-aminobutyric acid, glutamate, acetylcholine, and opioid peptides. The emphasis is on assessment of the availability of appropriate translational tools (PET radioligands, pharmacological challenge agents) and on studies in non-human primates and human subjects, as well as current challenges and future directions. CONCLUSIONS PET imaging directed at investigating changes in endogenous neurochemicals, including the work done in NEWMEDS, have highlighted an opportunity to further extend the capability and application of this technology in drug development.
Collapse
Affiliation(s)
- Sjoerd J. Finnema
- />Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Stockholm, Sweden
| | - Mika Scheinin
- />Department of Pharmacology, Drug Development and Therapeutics, University of Turku, Turku, Finland , />Unit of Clinical Pharmacology, Turku University Hospital, Turku, Finland
| | - Mohammed Shahid
- />Research and Development, Orion Corporation, Orion Pharma, Turku, Finland
| | - Jussi Lehto
- />Department of Pharmacology, Drug Development and Therapeutics, University of Turku, Turku, Finland
| | - Edilio Borroni
- />Neuroscience Department, Hoffman-La Roche, Basel, Switzerland
| | | | - Jukka Sallinen
- />Research and Development, Orion Corporation, Orion Pharma, Turku, Finland
| | - Erik Wong
- />Neuroscience Innovative Medicine Unit, AstraZeneca, Wilmington, DE USA
| | - Lars Farde
- />Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Stockholm, Sweden , />Translational Science Center at Karolinska Institutet, AstraZeneca, Stockholm, Sweden
| | - Christer Halldin
- />Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Stockholm, Sweden
| | - Sarah Grimwood
- Neuroscience Research Unit, Pfizer Inc, Cambridge, MA, USA. .,, 610 Main Street, Cambridge, MA, 02139, USA.
| |
Collapse
|
50
|
Serotonin 2A receptor agonist binding in the human brain with [¹¹C]Cimbi-36. J Cereb Blood Flow Metab 2014; 34:1188-96. [PMID: 24780897 PMCID: PMC4083382 DOI: 10.1038/jcbfm.2014.68] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Revised: 03/26/2014] [Accepted: 03/27/2014] [Indexed: 11/08/2022]
Abstract
[(11)C]Cimbi-36 was recently developed as a selective serotonin 2A (5-HT(2A)) receptor agonist radioligand for positron emission tomography (PET) brain imaging. Such an agonist PET radioligand may provide a novel, and more functional, measure of the serotonergic system and agonist binding is more likely than antagonist binding to reflect 5-HT levels in vivo. Here, we show data from a first-in-human clinical trial with [(11)C]Cimbi-36. In 29 healthy volunteers, we found high brain uptake and distribution according to 5-HT(2A) receptors with [(11)C]Cimbi-36 PET. The two-tissue compartment model using arterial input measurements provided the most optimal quantification of cerebral [(11)C]Cimbi-36 binding. Reference tissue modeling was feasible as it induced a negative but predictable bias in [(11)C]Cimbi-36 PET outcome measures. In five subjects, pretreatment with the 5-HT(2A) receptor antagonist ketanserin before a second PET scan significantly decreased [(11)C]Cimbi-36 binding in all cortical regions with no effects in cerebellum. These results confirm that [(11)C]Cimbi-36 binding is selective for 5-HT(2A) receptors in the cerebral cortex and that cerebellum is an appropriate reference tissue for quantification of 5-HT(2A) receptors in the human brain. Thus, we here describe [(11)C]Cimbi-36 as the first agonist PET radioligand to successfully image and quantify 5-HT(2A) receptors in the human brain.
Collapse
|