1
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Pressl C, Mätlik K, Kus L, Darnell P, Luo JD, Paul MR, Weiss AR, Liguore W, Carroll TS, Davis DA, McBride J, Heintz N. Selective vulnerability of layer 5a corticostriatal neurons in Huntington's disease. Neuron 2024; 112:924-941.e10. [PMID: 38237588 DOI: 10.1016/j.neuron.2023.12.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 08/18/2023] [Accepted: 12/13/2023] [Indexed: 01/30/2024]
Abstract
The properties of the cell types that are selectively vulnerable in Huntington's disease (HD) cortex, the nature of somatic CAG expansions of mHTT in these cells, and their importance in CNS circuitry have not been delineated. Here, we employed serial fluorescence-activated nuclear sorting (sFANS), deep molecular profiling, and single-nucleus RNA sequencing (snRNA-seq) of motor-cortex samples from thirteen predominantly early stage, clinically diagnosed HD donors and selected samples from cingulate, visual, insular, and prefrontal cortices to demonstrate loss of layer 5a pyramidal neurons in HD. Extensive mHTT CAG expansions occur in vulnerable layer 5a pyramidal cells, and in Betz cells, layers 6a and 6b neurons that are resilient in HD. Retrograde tracing experiments in macaque brains identify layer 5a neurons as corticostriatal pyramidal cells. We propose that enhanced somatic mHTT CAG expansion and altered synaptic function act together to cause corticostriatal disconnection and selective neuronal vulnerability in HD cerebral cortex.
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Affiliation(s)
- Christina Pressl
- Laboratory of Molecular Biology, The Rockefeller University, New York, NY, USA
| | - Kert Mätlik
- Laboratory of Molecular Biology, The Rockefeller University, New York, NY, USA
| | - Laura Kus
- Laboratory of Molecular Biology, The Rockefeller University, New York, NY, USA
| | - Paul Darnell
- Laboratory of Molecular Biology, The Rockefeller University, New York, NY, USA
| | - Ji-Dung Luo
- Bioinformatics Resource Center, The Rockefeller University, New York, NY, USA
| | - Matthew R Paul
- Bioinformatics Resource Center, The Rockefeller University, New York, NY, USA
| | - Alison R Weiss
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, USA
| | - William Liguore
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, USA
| | - Thomas S Carroll
- Bioinformatics Resource Center, The Rockefeller University, New York, NY, USA
| | - David A Davis
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Jodi McBride
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, USA
| | - Nathaniel Heintz
- Laboratory of Molecular Biology, The Rockefeller University, New York, NY, USA.
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2
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Pressl C, Mätlik K, Kus L, Darnell P, Luo JD, Paul MR, Weiss AR, Liguore W, Carroll TS, Davis DA, McBride J, Heintz N. Selective Vulnerability of Layer 5a Corticostriatal Neurons in Huntington's Disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.24.538096. [PMID: 37162977 PMCID: PMC10168234 DOI: 10.1101/2023.04.24.538096] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The properties of the cell types that are selectively vulnerable in Huntington's disease (HD) cortex, the nature of somatic CAG expansions of mHTT in these cells, and their importance in CNS circuitry have not been delineated. Here we employed serial fluorescence activated nuclear sorting (sFANS), deep molecular profiling, and single nucleus RNA sequencing (snRNAseq) to demonstrate that layer 5a pyramidal neurons are vulnerable in primary motor cortex and other cortical areas of HD donors. Extensive mHTT -CAG expansions occur in vulnerable layer 5a pyramidal cells, and in Betz cells, layer 6a, layer 6b neurons that are resilient in HD. Retrograde tracing experiments in macaque brains identify the vulnerable layer 5a neurons as corticostriatal pyramidal cells. We propose that enhanced somatic mHTT -CAG expansion and altered synaptic function act together to cause corticostriatal disconnection and selective neuronal vulnerability in the HD cerebral cortex.
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3
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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.
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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
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4
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Mangeant R, Dubost E, Cailly T, Collot V. Radiotracers for the Central Serotoninergic System. Pharmaceuticals (Basel) 2022; 15:ph15050571. [PMID: 35631397 PMCID: PMC9143978 DOI: 10.3390/ph15050571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 04/27/2022] [Accepted: 04/28/2022] [Indexed: 12/10/2022] Open
Abstract
This review lists the most important radiotracers described so far for imaging the central serotoninergic system. Single-photon emission computed tomography and positron emission tomography radiotracers are reviewed and critically discussed for each receptor.
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Affiliation(s)
- Reynald Mangeant
- Centre d’Etudes et de Recherche sur le Médicament de Normandie (CERMN), UNICAEN, Normandie Univ., 14000 Caen, France; (R.M.); (E.D.)
- Institut Blood and Brain @ Caen Normandie (BB@C), Boulevard Henri Becquerel, 14000 Caen, France
| | - Emmanuelle Dubost
- Centre d’Etudes et de Recherche sur le Médicament de Normandie (CERMN), UNICAEN, Normandie Univ., 14000 Caen, France; (R.M.); (E.D.)
- Institut Blood and Brain @ Caen Normandie (BB@C), Boulevard Henri Becquerel, 14000 Caen, France
| | - Thomas Cailly
- Centre d’Etudes et de Recherche sur le Médicament de Normandie (CERMN), UNICAEN, Normandie Univ., 14000 Caen, France; (R.M.); (E.D.)
- Institut Blood and Brain @ Caen Normandie (BB@C), Boulevard Henri Becquerel, 14000 Caen, France
- UNICAEN, IMOGERE, Normandie Univ., 14000 Caen, France
- CHU Côte de Nacre, Department of Nuclear Medicine, 14000 Caen, France
- Correspondence: (T.C.); (V.C.)
| | - Valérie Collot
- Centre d’Etudes et de Recherche sur le Médicament de Normandie (CERMN), UNICAEN, Normandie Univ., 14000 Caen, France; (R.M.); (E.D.)
- Institut Blood and Brain @ Caen Normandie (BB@C), Boulevard Henri Becquerel, 14000 Caen, France
- Correspondence: (T.C.); (V.C.)
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5
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Millan MJ. Agomelatine for the treatment of generalized anxiety disorder: focus on its distinctive mechanism of action. Ther Adv Psychopharmacol 2022; 12:20451253221105128. [PMID: 35795687 PMCID: PMC9251978 DOI: 10.1177/20451253221105128] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 03/04/2022] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED Generalized anxiety disorder (GAD), the most frequently diagnosed form of anxiety, is usually treated by cognitive-behavioural approaches or medication; in particular, benzodiazepines (acutely) and serotonin or serotonin/noradrenaline reuptake inhibitors (long term). Efficacy, compliance, and acceptability are, however, far from ideal, reinforcing interest in alternative options. Agomelatine, clinically employed in the treatment of major depression, expresses anxiolytic properties in rodents and was effective in the treatment of GAD (including severely ill patients) in several double-blind, short-term (12 weeks) and relapse-prevention (6 months) studies. At active doses, the incidence of adverse effects was no higher than for placebo. Agomelatine possesses a unique binding profile, behaving as a melatonin (MT1/MT2) receptor agonist and 5-HT2C receptor antagonist, yet recognizing neither monoamine transporters nor GABAA receptors. Extensive evidence supports a role for 5-HT2C receptors in the induction of anxious states, and their blockade likely plays a primary role in mediating the anxiolytic actions of agomelatine, including populations in the amygdala and bed nucleus of stria terminalis, as well as the hippocampus. Recruitment of MT receptors in the suprachiasmatic nucleus, thalamic reticular nucleus, and hippocampus appears to fulfil a complimentary role. Downstream of 5-HT2C and MT receptors, modulation of stress-sensitive glutamatergic circuits and altered release of the anxiogenic neuropeptides, corticotrophin-releasing factor, and vasopressin, may be implicated in the actions of agomelatine. To summarize, agomelatine exerts its anxiolytic actions by mechanisms clearly distinct from those of other agents currently employed for the management of GAD. PLAIN LANGUAGE SUMMARY How agomelatine helps in the treatment of anxiety disorders. INTRODUCTION • Anxiety disorders have a significant negative impact on quality of life.• The most common type of anxiety disorder, called generalized anxiety disorder (GAD), is associated with nervousness and excessive worry.• These symptoms can lead to additional symptoms like tiredness, sleeplessness, irritability, and poor attention.• GAD is generally treated through either cognitive-behavioural therapy or medication. However, widely used drugs like benzodiazepines and serotonin reuptake inhibitors have adverse effects.• Agomelatine, a well-established antidepressant drug, has shown anxiety-lowering ('anxiolytic') properties in rats and has been shown to effectively treat GAD with minimal side effects.• However, exactly how it acts on the brain to manage GAD is not yet clear.• Thus, this review aims to shed light on agomelatine's mechanism of action in treating GAD. METHODS • The authors reviewed studies on how agomelatine treats anxiety in animals.• They also looked at clinical studies on the effects of agomelatine in people with GAD. RESULTS • The study showed that agomelatine 'blocks' a receptor in nerve cells, which plays a role in causing anxiety, called the 5-HT2C receptor.• Blocking this receptor, especially in specific brain regions such as nerve cells of the amygdala, bed nucleus of stria terminalis, and hippocampus, produced the anxiety reduction seen during agomelatine treatment.• Agomelatine also activates the melatonin (MT) receptor, which is known to keep anxiety in check, promote sleep, and maintain the sleep cycle.• Agomelatine should thus tackle sleep disturbances commonly seen in patients with GAD.• Beyond 5-HT2C and MT receptors, signalling molecules in nerve cells that are known to be involved in anxiety disorders (called 'neurotransmitters' and 'neuropeptides') are also affected by agomelatine. CONCLUSION • Agomelatine's anxiolytic effects are caused by mechanisms that are distinct from those of other medications currently used to treat GAD.• This explains its therapeutic success and minimal adverse side effects.
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Affiliation(s)
- Mark J Millan
- Institute of Neuroscience and Psychology, College of Medicine, Vet and Life Sciences, Glasgow University, 28 Hillhead Street, Glasgow G12 8QB, UK
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6
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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.
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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
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7
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Takamura Y, Kakuta H. In Vivo Receptor Visualization and Evaluation of Receptor Occupancy with Positron Emission Tomography. J Med Chem 2021; 64:5226-5251. [PMID: 33905258 DOI: 10.1021/acs.jmedchem.0c01714] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Positron emission tomography (PET) is useful for noninvasive in vivo visualization of disease-related receptors, for evaluation of receptor occupancy to determine an appropriate drug dosage, and for proof-of-concept of drug candidates in translational research. For these purposes, the specificity of the PET tracer for the target receptor is critical. Here, we review work in this area, focusing on the chemical structures of reported PET tracers, their Ki/Kd values, and the physical properties relevant to target receptor selectivity. Among these physical properties, such as cLogP, cLogD, molecular weight, topological polar surface area, number of hydrogen bond donors, and pKa, we focus especially on LogD and LogP as important physical properties that can be easily compared across a range of studies. We discuss the success of PET tracers in evaluating receptor occupancy and consider likely future developments in the field.
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Affiliation(s)
- Yuta Takamura
- Division of Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 1-1-1, Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Hiroki Kakuta
- Division of Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 1-1-1, Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
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8
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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.
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9
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Deidda G, Crunelli V, Di Giovanni G. 5-HT/GABA interaction in epilepsy. PROGRESS IN BRAIN RESEARCH 2021; 259:265-286. [PMID: 33541679 DOI: 10.1016/bs.pbr.2021.01.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Epilepsy is a neurological condition characterized by synchronous neuronal oscillations (seizures) in the electroencephalogram. Seizures are classified in focal or generalized (depending on the brain territory interested during seizures), and in convulsive and/or not convulsive (depending on the presence or not of involuntary movements). The current pharmacological treatments are mainly based on GABA modulation although different neurotransmitters are also involved in epilepsy, including serotonin. However despite much extensive progress in the understanding of epilepsy mechanisms, still, a percentage of people with epilepsy are pharmaco-resistant calling for the need for new therapeutic targets. Here we review preclinical and human evidence showing that serotonin modulates epilepsy that this likely happens via a major modulation/interaction with GABA.
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Affiliation(s)
- Gabriele Deidda
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta.
| | - Vincenzo Crunelli
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta; Neuroscience Division, School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | - Giuseppe Di Giovanni
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta; Neuroscience Division, School of Biosciences, Cardiff University, Cardiff, United Kingdom
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10
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Pourfathi M, Kadlecek SJ, Chatterjee S, Rizi RR. Metabolic Imaging and Biological Assessment: Platforms to Evaluate Acute Lung Injury and Inflammation. Front Physiol 2020; 11:937. [PMID: 32982768 PMCID: PMC7487972 DOI: 10.3389/fphys.2020.00937] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 07/13/2020] [Indexed: 12/26/2022] Open
Abstract
Pulmonary inflammation is a hallmark of several pulmonary disorders including acute lung injury and acute respiratory distress syndrome. Moreover, it has been shown that patients with hyperinflammatory phenotype have a significantly higher mortality rate. Despite this, current therapeutic approaches focus on managing the injury rather than subsiding the inflammatory burden of the lung. This is because of the lack of appropriate non-invasive biomarkers that can be used clinically to assess pulmonary inflammation. In this review, we discuss two metabolic imaging tools that can be used to non-invasively assess lung inflammation. The first method, Positron Emission Tomography (PET), is widely used in clinical oncology and quantifies flux in metabolic pathways by measuring uptake of a radiolabeled molecule into the cells. The second method, hyperpolarized 13C MRI, is an emerging tool that interrogates the branching points of the metabolic pathways to quantify the fate of metabolites. We discuss the differences and similarities between these techniques and discuss their clinical applications.
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Affiliation(s)
- Mehrdad Pourfathi
- Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States
| | - Stephen J. Kadlecek
- Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States
| | - Shampa Chatterjee
- Department of Physiology, University of Pennsylvania, Philadelphia, PA, United States
| | - Rahim R. Rizi
- Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States
- *Correspondence: Rahim R. Rizi,
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11
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De Deurwaerdère P, Bharatiya R, Chagraoui A, Di Giovanni G. Constitutive activity of 5-HT receptors: Factual analysis. Neuropharmacology 2020; 168:107967. [DOI: 10.1016/j.neuropharm.2020.107967] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/26/2019] [Accepted: 01/12/2020] [Indexed: 12/16/2022]
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12
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Diaryliodoniums Salts as Coupling Partners for Transition-Metal Catalyzed C- and N-Arylation of Heteroarenes. Catalysts 2020. [DOI: 10.3390/catal10050483] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Owing to the pioneering works performed on the metal-catalyzed sp2 C–H arylation of indole and pyrrole by Sanford and Gaunt, N– and C-arylation involving diaryliodonium salts offers an attractive complementary strategy for the late-stage diversification of heteroarenes. The main feature of this expanding methodology is the selective incorporation of structural diversity into complex molecules which usually have several C–H bonds and/or N–H bonds with high tolerance to functional groups and under mild conditions. This review summarizes the main recent achievements reported in transition-metal-catalyzed N– and/or C–H arylation of heteroarenes using acyclic diaryliodonium salts as coupling partners.
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13
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Jang KS, Lee SS, Oh YH, Lee SH, Kim SE, Kim DW, Lee BC, Lee S, Raffel DM. Control of reactivity and selectivity of guanidinyliodonium salts toward 18F-Labeling by monitoring of protecting groups: Experiment and theory. J Fluor Chem 2019. [DOI: 10.1016/j.jfluchem.2019.109387] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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14
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Kim J, Kim YJ, Londhe AM, Pae AN, Choo H, Kim HJ, Min SJ. Synthesis and Biological Evaluation of Disubstituted Pyrimidines as Selective 5-HT 2C Agonists. Molecules 2019; 24:molecules24183234. [PMID: 31491978 PMCID: PMC6767204 DOI: 10.3390/molecules24183234] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 08/31/2019] [Accepted: 09/03/2019] [Indexed: 01/08/2023] Open
Abstract
Here, we describe the synthesis of disubstituted pyrimidine derivatives and their biological evaluation as selective 5-HT2C agonists. To improve selectivity for 5-HT2C over other subtypes, we synthesized two series of disubstituted pyrimidines with fluorophenylalkoxy groups at either the 5-position or 4-position and varying cyclic amines at the 2-position. The in vitro cell-based assay and binding assay identified compounds 10a and 10f as potent 5-HT2C agonists. Further studies on selectivity to 5-HT subtypes and drug-like properties indicated that 2,4-disubstituted pyrimidine 10a showed a highly agonistic effect on the 5-HT2C receptor, with excellent selectivity, as well as exceptional drug-like properties, including high plasma and microsomal stability, along with low CYP inhibition. Thus, pyrimidine 10a could be considered a viable lead compound as a 5-HT2C selective agonist.
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Affiliation(s)
- Juhyeon Kim
- Center for Neuro-Medicine, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea
- Department of Chemistry, Korea University, Seoul 02841, Korea
| | - Yoon Jung Kim
- Department of Applied Chemistry, Hanyang University, Ansan, Gyeonggi-do 15588, Korea
| | - Ashwini M Londhe
- Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology, Seoul 02792, Korea
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Korea Institute of Science and Technology, Seoul 02792, Korea
| | - Ae Nim Pae
- Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology, Seoul 02792, Korea
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Korea Institute of Science and Technology, Seoul 02792, Korea
| | - Hyunah Choo
- Center for Neuro-Medicine, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea
- Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology, Seoul 02792, Korea
| | - Hak Joong Kim
- Department of Chemistry, Korea University, Seoul 02841, Korea
| | - Sun-Joon Min
- Department of Applied Chemistry, Hanyang University, Ansan, Gyeonggi-do 15588, Korea.
- Department of Chemical & Molecular Engineering, Hanyang University, Ansan, Gyeonggi-do 15588, Korea.
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15
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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.
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16
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Pike VW. Hypervalent aryliodine compounds as precursors for radiofluorination. J Labelled Comp Radiopharm 2018; 61:196-227. [PMID: 28981159 PMCID: PMC10081107 DOI: 10.1002/jlcr.3570] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 09/27/2017] [Indexed: 12/12/2022]
Abstract
Over the last 2 decades or so, hypervalent iodine compounds, such as diaryliodonium salts and aryliodonium ylides, have emerged as useful precursors for labeling homoarenes and heteroarenes with no-carrier-added cyclotron-produced [18 F]fluoride ion (t1/2 = 109.8 min). They permit rapid and effective radiofluorination at electron-rich as well as electron-deficient aryl rings, and often with unrestricted choice of ring position. Consequently, hypervalent aryliodine compounds have found special utility as precursors to various small-molecule 18 F-labeling synthons and to many radiotracers for biomedical imaging with positron emission tomography. This review summarizes this advance in radiofluorination chemistry, with emphasis on precursor synthesis, radiofluorination mechanism, method scope, and method application.
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Affiliation(s)
- Victor W Pike
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
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18
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Kim J, Jo H, Lee H, Choo H, Kim HJ, Pae AN, Cho YS, Min SJ. Identification of Optically Active Pyrimidine Derivatives as Selective 5-HT 2C Modulators. Molecules 2017; 22:molecules22091416. [PMID: 28846591 PMCID: PMC6151589 DOI: 10.3390/molecules22091416] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 08/22/2017] [Accepted: 08/23/2017] [Indexed: 11/16/2022] Open
Abstract
A series of pyrimidine derivatives 4a-i were synthesized and evaluated for their binding affinities towards 5-HT2C receptors. With regard to designed molecules 4a-i, the influence of the size of alkyl ether and the absolute configuration of a stereogenic center on the 5-HT2C binding affinity and selectivity was studied. The most promising diasteromeric mixtures 4d and 4e were selected in the initial radioligand binding assay and they were further synthesized as optically active forms starting from optically active alcohols 5d and 5e, prepared by an enzymatic kinetic resolution. Pyrimidine analogue (R,R)-4e displayed an excellent 5-HT2C binding affinity with good selectivity values against a broad range of other 5-HT receptor subtypes.
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Affiliation(s)
- Juhyeon Kim
- Center for Neuro-Medicine, Korea Institute of Science and Technology (KIST), 5 Hwarangno 14-gil, Seongbuk-gu, Seoul 02792, Korea.
- Department of Chemistry, Korea University, Seoul 02841, Korea.
| | - Hanbyeol Jo
- Department of Chemical & Molecular Engineering/Applied Chemistry, Hanyang University, Ansan, Gyeonggi-do 15588, Korea.
| | - Hyunseung Lee
- Department of Chemical & Molecular Engineering/Applied Chemistry, Hanyang University, Ansan, Gyeonggi-do 15588, Korea.
| | - Hyunah Choo
- Center for Neuro-Medicine, Korea Institute of Science and Technology (KIST), 5 Hwarangno 14-gil, Seongbuk-gu, Seoul 02792, Korea.
- Department of Biological Chemistry, Korea University of Science and Technology (UST), 217 Gajungro, Yuseong-gu, Daejeon 34113, Korea.
| | - Hak Joong Kim
- Department of Chemistry, Korea University, Seoul 02841, Korea.
| | - Ae Nim Pae
- Department of Biological Chemistry, Korea University of Science and Technology (UST), 217 Gajungro, Yuseong-gu, Daejeon 34113, Korea.
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, KIST, Seoul 02792, Korea.
| | - Yong Seo Cho
- Center for Neuro-Medicine, Korea Institute of Science and Technology (KIST), 5 Hwarangno 14-gil, Seongbuk-gu, Seoul 02792, Korea.
- Department of Biological Chemistry, Korea University of Science and Technology (UST), 217 Gajungro, Yuseong-gu, Daejeon 34113, Korea.
| | - Sun-Joon Min
- Department of Chemical & Molecular Engineering/Applied Chemistry, Hanyang University, Ansan, Gyeonggi-do 15588, Korea.
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Innovative Clinical Trial Designs for Precision Medicine in Heart Failure with Preserved Ejection Fraction. J Cardiovasc Transl Res 2017; 10:322-336. [PMID: 28681133 DOI: 10.1007/s12265-017-9759-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Accepted: 06/13/2017] [Indexed: 12/17/2022]
Abstract
A major challenge in the care of patients with heart failure and preserved ejection fraction (HFpEF) is the lack of proven therapies due to disappointing results from randomized controlled trials (RCTs). The heterogeneity of the HFpEF syndrome and the use of conventional RCT designs are possible reasons underlying the failure of these trials. There are several factors-including the widespread adoption of electronic health records, decreasing costs of obtaining high-dimensional data, and the availability of a wide variety of potential therapeutics-that have evolved to enable more innovative clinical trial designs in HFpEF. Here, we review the current landscape of HFpEF RCTs and present several innovative RCT designs that could be implemented in HFpEF, including enrichment trials, adaptive trials, umbrella trials, basket trials, and machine learning-based trials (including examples for each). Our hope is that the description of the aforementioned innovative trial designs will stimulate new approaches to clinical trials in HFpEF.
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Abstract
In the current issue of ACS Chemical Neuroscience, Kim et al. report on the early characterization of 4-(3-[18F] fluorophenethoxy)pyrimidine (18F-FPP) as a new positron emission tomography radiotracer for imaging brain 5-HT2C receptors ( Kim, J., et al. ( 2017 ) A potential PET radiotracer for the 5-HT2c receptor: Synthesis and in vivo evaluation of 4-(3-[18F]Fluorophenethoxy)pyrimidine. ACS Chem. Neurosci. , DOI 10.1021/acschemneuro.6b00445 ). At the present time, the tracer properties of 18F-FPP have only been reported in rats. If 18F-FPP is indeed shown to be suitable as a 5-HT2C receptor PET tracer in humans, it will very likely have an important impact both in the development of any new chemical entities (NCEs) targeted to 5-HT2C receptors, as well as a tool to advance understanding of 5-HT2C receptor function both in normal and abnormal brain states.
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Affiliation(s)
- Guy A. Higgins
- InterVivo Solutions Inc., 120 Carlton Street, Toronto, ON M5A
4K2, Canada
- Department of Pharmacology & Toxicology, University of Toronto, 1 King’s College Circle, Toronto, ON M5S 1A8, Canada
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