1
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Gacoin M, Ben Hamed S. Fluoxetine degrades luminance perceptual thresholds while enhancing motivation and reward sensitivity. Front Pharmacol 2023; 14:1103999. [PMID: 37153796 PMCID: PMC10157648 DOI: 10.3389/fphar.2023.1103999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 03/30/2023] [Indexed: 05/10/2023] Open
Abstract
Selective serotonin reuptake inhibitors (SSRIs) increase serotonin activity in the brain. While they are mostly known for their antidepressant properties, they have been shown to improve visual functions in amblyopia and impact cognitive functions ranging from attention to motivation and sensitivity to reward. Yet, a clear understanding of the specific action of serotonin to each of bottom-up sensory and top-down cognitive control components and their interaction is still missing. To address this question, we characterize, in two adult male macaques, the behavioral effects of fluoxetine, a specific SSRI, on visual perception under varying bottom-up (luminosity, distractors) and top-down (uncertainty, reward biases) constraints while they are performing three different visual tasks. We first manipulate target luminosity in a visual detection task, and we show that fluoxetine degrades luminance perceptual thresholds. We then use a target detection task in the presence of spatial distractors, and we show that under fluoxetine, monkeys display both more liberal responses as well as a degraded perceptual spatial resolution. In a last target selection task, involving free choice in the presence of reward biases, we show that monkeys display an increased sensitivity to reward outcome under fluoxetine. In addition, we report that monkeys produce, under fluoxetine, more trials and less aborts, increased pupil size, shorter blink durations, as well as task-dependent changes in reaction times. Overall, while low level vision appears to be degraded by fluoxetine, performances in the visual tasks are maintained under fluoxetine due to enhanced top-down control based on task outcome and reward maximization.
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Affiliation(s)
- Maëva Gacoin
- *Correspondence: Maëva Gacoin, ; Suliann Ben Hamed,
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2
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Tsai CJ, Chiu CH, Kuo YY, Huang WS, Yu TH, Flores LG, Yeh SHH, Ma KH. 3,4-Methylenedioxymethamphetamine (MDMA) Model: In Vivo 4-[18F]-ADAM PET Imaging. Int J Mol Sci 2022; 23:ijms23137035. [PMID: 35806049 PMCID: PMC9266335 DOI: 10.3390/ijms23137035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 06/20/2022] [Accepted: 06/22/2022] [Indexed: 11/25/2022] Open
Abstract
Numerous studies have confirmed that 3,4-Methylenedioxymethamphetamine (MDMA) produces long-lasting changes to the density of the serotonin reuptake transporter (SERT). Amitriptyline (AMI) has been shown to exert neuroprotective properties in neuropathologic injury. Here, we used a SERT-specific radionuclide, 4-[18F]-ADAM, to assess the longitudinal alterations in SERT binding and evaluate the synergistic neuroprotective effect of AMI in a rat MDMA model. In response to MDMA treatment regimens, SERT binding was significantly reduced in rat brains. Region-specific recovery rate (normalized to baseline) in the MDMA group at day 14 was 71.29% ± 3.21%, and progressively increased to 90.90% ± 7.63% at day 35. AMI dramatically increased SERT binding in all brain regions, enhancing average ~18% recovery rate at day 14 when compared with the MDMA group. The immunochemical staining revealed that AMI markedly increased the serotonergic fiber density in the cingulate and thalamus after MDMA-induction, and confirmed the PET findings. Using in vivo longitudinal PET imaging, we demonstrated that SERT recovery was positively correlated with the duration of MDMA abstinence, implying that lower SERT densities in MDMA-induced rats reflected neurotoxic effects and were (varied) region-specific and reversible. AMI globally accelerated the recovery rate of SERT binding and increased SERT fiber density with possible neuroprotective effects.
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Affiliation(s)
- Chi-Jung Tsai
- Department of Nuclear Medicine, Taipei Medical University Hospital, Taipei 110, Taiwan; (C.-J.T.); (W.-S.H.)
| | - Chuang-Hsin Chiu
- Department of Nuclear Medicine, Tri-Service General Hospital, Taipei 114, Taiwan;
| | - Yu-Yeh Kuo
- Department of Nursing, Hsin-Sheng College of Medical Care and Management, Taoyuan 325, Taiwan;
| | - Wen-Sheng Huang
- Department of Nuclear Medicine, Taipei Medical University Hospital, Taipei 110, Taiwan; (C.-J.T.); (W.-S.H.)
- Department of Nuclear Medicine, Cheng-Hsin General Hospital, Taipei 112, Taiwan
| | - Tsung-Hsun Yu
- Brain Research Center, National Yang Ming Chaio Tung University, Taipei 112, Taiwan; (T.-H.Y.); (S.H.-H.Y.)
| | | | - Skye Hsin-Hsien Yeh
- Brain Research Center, National Yang Ming Chaio Tung University, Taipei 112, Taiwan; (T.-H.Y.); (S.H.-H.Y.)
- School of Medicine, National Defense Medical Center, Taipei 110, Taiwan
| | - Kuo-Hsing Ma
- Department of Biology and Anatomy, National Defense Medi Center, Taipei 110, Taiwan
- Correspondence: ; Tel.: +886-2-8792-3100 (ext. 18728 or 18081)
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3
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Mangeant R, Dubost E, Cailly T, Collot V. Radiotracers for the Central Serotoninergic System. Pharmaceuticals (Basel) 2022; 15:571. [PMID: 35631397 PMCID: PMC9143978 DOI: 10.3390/ph15050571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [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
| | - 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
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4
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Sgambato V. Breathing new life into neurotoxic-based monkey models of Parkinson's disease to study the complex biological interplay between serotonin and dopamine. PROGRESS IN BRAIN RESEARCH 2020; 261:265-285. [PMID: 33785131 DOI: 10.1016/bs.pbr.2020.07.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Numerous clinical studies have shown that the serotonergic system also degenerates in patients with Parkinson's disease. The causal role of this impairment in Parkinson's symptomatology and the response to treatment remains to be refined, in particular thanks to approaches allowing the two components DA and 5-HT to be isolated if possible. We have developed a macaque monkey model of Parkinson's disease exhibiting a double lesion (dopaminergic and serotonergic) thanks to the sequential use of MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) and MDMA (3,4-methylenedioxy-N-methamphetamine) (or MDMA prior MPTP). We characterized this monkey model by multimodal imaging (PET, positron emission tomography with several radiotracers; DTI, diffusion tensor imaging), behavioral assessments (parkinsonism, dyskinesia, neuropsychiatric-like behavior) and post-mortem analysis (with DA and 5-HT markers). When administrated after MPTP, MDMA damaged the 5-HT presynaptic system without affecting the remaining DA neurons. The lesion of 5-HT fibers induced by MDMA altered rigidity and prevented dyskinesia and neuropsychiatric-like symptoms induced by levodopa therapy in MPTP-treated animals. Interestingly also, prior MDMA administration aggravates the parkinsonian deficits and associated DA injury. Dystonic postures, action tremor and global spontaneous activities were significantly affected. All together, these data clearly indicate that late or early lesions of the 5-HT system have a differential impact on parkinsonian symptoms in the macaque model of Parkinson's disease. Whether MDMA has an impact on neuropsychiatric-like symptoms such as apathy, anxiety, depression remains to be addressed. Despite its limitations, this toxin-based double-lesioned monkey model takes on its full meaning and provides material for the experimental study of the heterogeneity of patients.
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Affiliation(s)
- Véronique Sgambato
- Université de Lyon, CNRS UMR 5229, Institut des Sciences Cognitives Marc Jeannerod, Bron, France.
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5
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Shih JH, Chiu CH, Ma KH, Huang YS, Shiue CY, Yeh TY, Kao LT, Lin YY, Li IH. Autophagy inhibition plays a protective role against 3, 4-methylenedioxymethamphetamine (MDMA)-induced loss of serotonin transporters and depressive-like behaviors in rats. Pharmacol Res 2019; 142:283-293. [PMID: 30826457 DOI: 10.1016/j.phrs.2019.02.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Revised: 12/27/2018] [Accepted: 02/24/2019] [Indexed: 02/06/2023]
Abstract
The 3,4-methylenedioxymethamphetamine (MDMA) is a popular recreational drug, which ultimately leads to serotonergic (5-HT) neurotoxicity and psychiatric disorders. Previous in vitro studies have consistently demonstrated that MDMA provokes autophagic activation, as well as damage of 5-HT axons and nerve fibers. So far, whether autophagy, a well-conserved cellular process that is critical for cell fate, also participates in MDMA-induced neurotoxicity in vivo remains elusive. Here, we first examined time-course of autophagy-related changes during repeated administration of MDMA (10 mg/kg s.c. twice daily for 4 consecutive days) using immunofluorescent staining for tryptophan hydroxylase and microtubule-associated protein 1 light chain 3 beta in rats. We also evaluated the protective effects of 3-methyadanine (3-MA, an autophagy inhibitor, 15 mg/kg i.p.) against MDMA-induced acute and long-term reductions in serotonin transporters (SERT) density in various brain regions using immunohistochemical staining and positron emission tomography (PET) imaging respectively. Plasma corticosterone measurements and forced swim tests were performed to evaluate the depressive performance. The staining results showed that repeated administration of MDMA increased expression of autophagosome and caused reduction in SERT densities of striatum and frontal cortex, which was ameliorated in the presence of 3-MA. PET imaging data also revealed that 3-MA could ameliorate MDMA-induced long-term decreased SERT availability in various brain regions of rats. Furthermore, immobility time of forced swim tests and plasma corticosterone levels were less in the group of MDMA co-injected with 3-MA compared with that of MDMA group. Together, these findings suggest that autophagy inhibition may confer protection against neurobiological and behavioral changes induced by MDMA.
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Affiliation(s)
- Jui-Hu Shih
- Department of Pharmacy Practice, Tri-Service General Hospital, Taipei, Taiwan; School of Pharmacy, National Defense Medical Center, Taipei, Taiwan
| | - Chuang-Hsin Chiu
- Department of Nuclear Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Kuo-Hsing Ma
- Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan
| | - Yuahn-Sieh Huang
- Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan
| | - Chyng-Yann Shiue
- Department of Nuclear Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Ting-Yin Yeh
- Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan
| | - Li-Ting Kao
- Department of Pharmacy Practice, Tri-Service General Hospital, Taipei, Taiwan; Graduate Institute of Life Science, National Defense Medical Center, Taipei, Taiwan
| | - Yang-Yi Lin
- Department of Pharmacy, Chi Mei Medical Center, Tainan, Taiwan
| | - I-Hsun Li
- Department of Pharmacy Practice, Tri-Service General Hospital, Taipei, Taiwan; School of Pharmacy, National Defense Medical Center, Taipei, Taiwan.
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6
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Zhang Y, Liu F, Xiao H, Yao X, Li G, Choi SR, Ploessl K, Zha Z, Zhu L, Kung HF. Fluorine-18 labeled diphenyl sulfide derivatives for imaging serotonin transporter (SERT) in the brain. Nucl Med Biol 2018; 66:1-9. [PMID: 30096380 DOI: 10.1016/j.nucmedbio.2018.06.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 06/15/2018] [Accepted: 06/28/2018] [Indexed: 02/06/2023]
Abstract
OBJECTIVES Serotonin transporters (SERT) play an important role in controlling serotonin concentration in the synaptic cleft and in managing postsynaptic signal transduction. Inhibitors of SERT binding are well known as selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine, sertraline, paroxetine, and escitalopram, that are commonly prescribed antidepressants. Positron emission tomography (PET) and single photon emission tomography (SPECT) imaging agents targeting SERT may be useful for studying its function and providing a tool for monitoring drug treatment. METHODS A series of novel 18F-labeled diphenyl sulfide derivatives were prepared and tested for their binding affinity. Among them, 2-((2-((dimethylamino)-methyl)-4-(2-(2-fluoroethoxy)ethoxy)phenyl)thio)aniline, 1, which showed excellent binding toward serotonin transporter (SERT) in the brain (Ki = 0.09 nM), was selected for further evaluation. An active OTs intermediate, 7, was treated with [18F]F-/K222 to provide [18F]1 in one step and in high radiochemical yields. This new SERT targeting agent was evaluated in rats by biodistribution studies and animal PET imaging studies. RESULTS The radiolabeling reaction led to the desired [18F]1. After HPLC purification no-carrier-added [18F]1 was obtained (radiochemical yield, 23-47% (n = 10,); radiochemical purity >99%; molar activity, 15-28 GBq/μmol). Biodistribution studies with [18F]1 showed good brain uptake (1.04% dose/g at 2 min post-injection), high uptake into the hypothalamus (1.55% dose/g at 30 min), and a high target-to-non-target (hypothalamus to cerebellum) ratio of 6.1 at 120 min post-injection. A PET imaging study in normal rats showed excellent uptake in the midbrain and thalamus regions known to be rich in SERT binding sites at 60 min after iv injection. Chasing experiment with escitalopram (iv, 2 mg/kg) in a rat at 60 min after iv injection caused a noticeable reduction in the regional radioactivity and the target-to-non-target ratio, suggesting binding by [18F]1 was highly specific and reversible for SERT binding sites in the brain. CONCLUSIONS A novel diphenyl sulfide derivative, [18F]1 for SERT imaging was successfully prepared and evaluated. Results suggest that this new chemical entity is targeting SERT binding sites in the brain, and it is a suitable candidate for future commercial development.
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Affiliation(s)
- Yan Zhang
- Key Laboratory of Radiopharmaceuticals (College of Chemistry), Beijing Normal University, Ministry of Education, Beijing, 100875, China
| | - Futao Liu
- Key Laboratory of Radiopharmaceuticals (College of Chemistry), Beijing Normal University, Ministry of Education, Beijing, 100875, China; Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Hao Xiao
- Key Laboratory of Radiopharmaceuticals (College of Chemistry), Beijing Normal University, Ministry of Education, Beijing, 100875, China
| | - Xinyue Yao
- Key Laboratory of Radiopharmaceuticals (College of Chemistry), Beijing Normal University, Ministry of Education, Beijing, 100875, China
| | - Genxun Li
- Key Laboratory of Radiopharmaceuticals (College of Chemistry), Beijing Normal University, Ministry of Education, Beijing, 100875, China
| | - Seok Rye Choi
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Karl Ploessl
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Zhihao Zha
- Beijing Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China
| | - Lin Zhu
- Key Laboratory of Radiopharmaceuticals (College of Chemistry), Beijing Normal University, Ministry of Education, Beijing, 100875, China; Beijing Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China.
| | - Hank F Kung
- Beijing Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China; Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
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7
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Liu F, Zhu L, Choi SR, Plössl K, Zha Z, Kung HF. Deuterium-substituted 2-(2′-((dimethylamino)methyl)-4′-[18
F](fluoropropoxy)phenylthio)benzenamine as a serotonin transporter imaging agent. J Labelled Comp Radiopharm 2018; 61:576-585. [DOI: 10.1002/jlcr.3626] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/28/2018] [Accepted: 03/29/2018] [Indexed: 01/06/2023]
Affiliation(s)
- Futao Liu
- Key Laboratory of Radiopharmaceuticals, Ministry of Education; Beijing Normal University; Beijing P. R. China
- Department of Radiology; University of Pennsylvania; Philadelphia Pennsylvania USA
| | - Lin Zhu
- Key Laboratory of Radiopharmaceuticals, Ministry of Education; Beijing Normal University; Beijing P. R. China
| | - Seok Rye Choi
- Department of Radiology; University of Pennsylvania; Philadelphia Pennsylvania USA
| | - Karl Plössl
- Department of Radiology; University of Pennsylvania; Philadelphia Pennsylvania USA
| | - Zhihao Zha
- Department of Radiology; University of Pennsylvania; Philadelphia Pennsylvania USA
| | - Hank F. Kung
- Department of Radiology; University of Pennsylvania; Philadelphia Pennsylvania USA
- Five Eleven Pharma Inc; Philadelphia Pennsylvania USA
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8
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Serotonergic targets for the treatment of L-DOPA-induced dyskinesia. J Neural Transm (Vienna) 2018; 125:1203-1216. [PMID: 29305656 DOI: 10.1007/s00702-017-1837-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 12/28/2017] [Indexed: 12/31/2022]
Abstract
Dopamine (DA) replacement therapy with L-3,4-dihydroxyphenylalanine (L-DOPA) continues to be the gold-standard treatment for Parkinson's disease (PD). Despite clear symptomatic benefit, long-term L-DOPA use often results in the development of L-DOPA-induced dyskinesia (LID), significantly reducing quality of life and increasing costs for PD patients and their caregivers. Accumulated research has demonstrated that several pre- and post-synaptic mechanisms contribute to LID development and expression. In particular, raphe-striatal hyperinnervation and unregulated DA release from 5-HT terminals is postulated to play a central role in LID manifestation. As such, manipulation of the 5-HT system has garnered considerable attention. Both pre-clinical and clinical research has supported the potential of modulating the 5-HT system for LID prevention and treatment. This review discusses the rationale for continued investigation of several potential anti-dyskinetic strategies including 5-HT stimulation of 5-HT1A and 5-HT1B receptors and blockade of 5-HT2A receptors and SERT. We present the latest findings from experimental and clinical investigations evaluating these 5-HT targets with the goal of identifying those with translational promise and the challenges associated with each.
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9
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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.
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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
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Sgambato-Faure V, Billard T, Météreau E, Duperrier S, Fieux S, Costes N, Tremblay L, Zimmer L. Characterization and Reliability of [ 18F]2FNQ1P in Cynomolgus Monkeys as a PET Radiotracer for Serotonin 5-HT 6 Receptors. Front Pharmacol 2017; 8:471. [PMID: 28769801 PMCID: PMC5513908 DOI: 10.3389/fphar.2017.00471] [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: 04/23/2017] [Accepted: 07/03/2017] [Indexed: 01/08/2023] Open
Abstract
Brain serotonin-6 receptor (5-HT6R) is the one of the most recently identified serotonin receptors. Accumulating evidence suggests that it is a potent therapeutic target for psychiatric and neurological diseases. Since [18F]2FNQ1P was recently proposed as the first fluorinated positron emission tomography (PET) radioligand for this receptor, the objective of the present study was to demonstrate its suitability for 5-HT6R neuroimaging in primates. [18F]2FNQ1P was characterized by in vitro autoradiography and in vivo PET imaging in cynomolgus monkeys. Following in vivo PET imaging, tracer binding indices were computed using the simplified reference tissue model and Logan graphical model, with cerebellum as reference region. The tracer binding reproducibility was assessed by test–retest in five animals. Finally, specificity was assessed by pre-injection of a 5-HT6R antagonist, SB258585. In vitro, results showed wide cerebral distribution of the tracer with specificity toward 5-HT6Rs as binding was effectively displaced by SB258585. In vivo brain penetration was good with reproducible distribution at cortical and subcortical levels. The automated method gave the best spatial normalization. The Logan graphical model showed the best tracer binding indices, giving the highest magnitude, lowest standard deviation and best reproducibility and robustness. Finally, 5-HT6R antagonist pre-injection significantly decreased [18F]2FNQ1P binding mainly in the striatum and sensorimotor cortex. Taken together, these preclinical results show that [18F]2FNQ1P is a good candidate to address 5-HT6 receptors in clinical studies.
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Affiliation(s)
- Véronique Sgambato-Faure
- Université Claude Bernard Lyon ILyon, France.,Institut des Sciences Cognitives Marc Jeannerod, CNRS UMR5229Bron, France
| | - Thierry Billard
- Université Claude Bernard Lyon ILyon, France.,Institut de Chimie et de Biochimie, CNRS UMR5246Villeurbanne, France
| | - Elise Météreau
- Université Claude Bernard Lyon ILyon, France.,Institut des Sciences Cognitives Marc Jeannerod, CNRS UMR5229Bron, France
| | - Sandra Duperrier
- Université Claude Bernard Lyon ILyon, France.,Institut des Sciences Cognitives Marc Jeannerod, CNRS UMR5229Bron, France
| | - Sylvain Fieux
- Université Claude Bernard Lyon ILyon, France.,Centre de Recherche en Neurosciences de Lyon, CNRS UMR5292, INSERM U1028Lyon, France
| | | | - Léon Tremblay
- Université Claude Bernard Lyon ILyon, France.,Institut des Sciences Cognitives Marc Jeannerod, CNRS UMR5229Bron, France
| | - Luc Zimmer
- Université Claude Bernard Lyon ILyon, France.,Centre de Recherche en Neurosciences de Lyon, CNRS UMR5292, INSERM U1028Lyon, France.,CERMEP-Imagerie du VivantLyon, France.,Hospices Civils de LyonLyon, France
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11
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Huot P, Sgambato-Faure V, Fox SH, McCreary AC. Serotonergic Approaches in Parkinson's Disease: Translational Perspectives, an Update. ACS Chem Neurosci 2017; 8:973-986. [PMID: 28460160 DOI: 10.1021/acschemneuro.6b00440] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Parkinson's disease (PD) has long been seen as a disorder caused by degeneration of the dopaminergic system, leading to the classic motor manifestations of the disease. However, there is now overwhelming evidence that PD is more than a disease merely caused by dopamine depletion. It is well-known that a myriad of other neurotransmitters are affected by the disease process. One such neurotransmitter is serotonin (5-HT). 5-HT has been shown to play a role in several motor and nonmotor manifestations of PD, including tremor, cognition, depression and psychosis. 5-HT also seems to play a critical role in L-3,4-dihydroxyphenylalanine (L-DOPA)-induced dyskinesia. A breadth of preclinical studies and clinical trials have been conducted that aimed at modulating the 5-HT system in order to alleviate depression, cognitive deficits, psychosis, and dyskinesia. In this Review, we summarize recent advances in the 5-HT field in PD, but with a translational emphasis. We start by presenting a novel nonhuman primate model of PD that presents with dual dopamine and 5-HT lesions. We then present preclinical and clinical data that introduce new concepts, such as the use of biased and partial agonists, as well as molecules recently introduced to the field of PD, such as eltoprazine, pimavanserin, nelotanserin, and SYN-120, to enhance therapeutic benefit while minimizing adverse events, notably on parkinsonian disability.
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Affiliation(s)
- Philippe Huot
- Centre de Recherche du Centre Hospitalier de l’Université de Montréal, Montreal, QC H2X 0A9, Canada
- Department
of Pharmacology, Université de Montréal, Montreal, QC H3T 1J4, Canada
- Unité
des Troubles du Mouvement André Barbeau, Centre Hospitalier de l’Université de Montréal, Montreal, QC H2L 4M1, Canada
- Division
of Neurology, Centre Hospitalier de l’Université de Montréal, Montreal, QC, Canada
| | - Véronique Sgambato-Faure
- Institute of Cognitive
Neuroscience Marc Jeannerod, UMR 5229 CNRS, 69 675 Cedex Bron, France
- University Lyon 1, 69100 Villeurbanne, France
| | - Susan H. Fox
- Movement
Disorder Clinic, Toronto Western Hospital, University of Toronto, Toronto, ON M5T2S8, Canada
| | - Andrew C. McCreary
- Janssen Vaccines & Prevention B.V., Archimedesweg 4, 2333 CN Leiden, The Netherlands
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12
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Huang L, Merson TD, Bourne JA. In vivo whole brain, cellular and molecular imaging in nonhuman primate models of neuropathology. Neurosci Biobehav Rev 2016; 66:104-18. [PMID: 27151822 DOI: 10.1016/j.neubiorev.2016.04.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 03/31/2016] [Accepted: 04/13/2016] [Indexed: 12/22/2022]
Abstract
Rodents have been the principal model to study brain anatomy and function due to their well-mapped brain architecture, rapid reproduction and amenability to genetic modification. However, there are clear limitations, for example their simpler neocortex, necessitating the need to adopt a model that is closer to humans in order to understand human cognition and brain conditions. Nonhuman primates (NHPs) are ideally suited as they are our closest relatives in the animal kingdom but in vivo imaging technologies to study brain structure and function in these species can be challenging. With the surge in NHP research in recent years, scientists have begun adapting imaging technologies, such as two-photon microscopy, for these species. Here we review the various NHP models that exist as well as their use in advanced microscopic and mesoscopic studies. We discuss the challenges in the field and investigate the opportunities that lie ahead.
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Affiliation(s)
- Lieven Huang
- Australian Regenerative Medicine Institute, Monash University, 15 Innovation Walk, Clayton, Victoria 3800, Australia
| | - Tobias D Merson
- The Florey Institute of Neuroscience and Mental Health, 30 Royal Parade, Parkville, Victoria, 3052, Australia
| | - James A Bourne
- Australian Regenerative Medicine Institute, Monash University, 15 Innovation Walk, Clayton, Victoria 3800, Australia.
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13
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Qiao H, Zhang Y, Wu Z, Zhu L, Choi SR, Ploessl K, Kung HF. One-step preparation of [(18)F]FPBM for PET imaging of serotonin transporter (SERT) in the brain. Nucl Med Biol 2016; 43:470-7. [PMID: 27236282 DOI: 10.1016/j.nucmedbio.2016.04.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 03/16/2016] [Accepted: 04/14/2016] [Indexed: 01/27/2023]
Abstract
Serotonin transporters (SERT) in the brain play an important role in normal brain function. Selective serotonin reuptake inhibitors such as fluoxetine, sertraline, paroxetine, escitalopram, etc., specifically target SERT binding in the brain. Development of SERT imaging agents may be useful for studying the function of SERT by in vivo imaging. A one-step preparation of [(18)F]FPBM, 2-(2'-(dimethylamino)methyl)-4'-(3-([(18)F]fluoropropoxy)phenylthio)benzenamine, for positron emission tomography (PET) imaging of SERT binding in the brain was achieved. An active OTs intermediate, 9, was reacted with [(18)F]F(-)/K222 to produce [(18)F]FPBM in one step and in high radiochemical yield. This labeling reaction was evaluated and optimized under different temperatures, bases, solvents, and varying amounts of precursor 9. The radiolabeling reaction led to the desired [(18)F]FPBM in one step and the crude product was purified by HPLC purification to give no-carrier-added [(18)F]FPBM (radiochemical yield, 24-33%, decay corrected; radiochemical purity >99%). PET imaging studies in normal monkeys (n=4) showed fast, pronounced uptakes in the midbrain and thalamus, regions known to be rich in SERT binding sites. A displacement experiment with escitalopram (5mg/kg iv injection at 30min after [(18)F]FPBM injection) showed a rapid and complete reversal of SERT binding, suggesting that binding by [(18)F]FPBM was highly specific and reversible. A one-step radiolabeling method coupled with HPLC purification for preparation of [(18)F]FPBM was developed. Imaging studies suggest that it is feasible to use this method to prepare [(18)F]FPBM for in vivo PET imaging of SERT binding in the brain.
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Affiliation(s)
- Hongwen Qiao
- Department of Neurobiology, Xuanwu Hospital of Capital Medical University, Beijing 100053, China; Beijing Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China; Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Yan Zhang
- Key Laboratory of Radiopharmaceuticals, Beijing Normal University, Ministry of Education, Beijing, 100875, China
| | - Zehui Wu
- Beijing Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China; Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Lin Zhu
- Beijing Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China; Key Laboratory of Radiopharmaceuticals, Beijing Normal University, Ministry of Education, Beijing, 100875, China; Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Seok Rye Choi
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Karl Ploessl
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Hank F Kung
- Beijing Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China; Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
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14
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Fully automated one-pot two-step synthesis of 4-[ 18 F]-ADAM, a potent serotonin transporter imaging agent. Appl Radiat Isot 2016; 110:8-15. [DOI: 10.1016/j.apradiso.2015.12.052] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 12/15/2015] [Accepted: 12/20/2015] [Indexed: 11/19/2022]
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15
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Vegting Y, Reneman L, Booij J. The effects of ecstasy on neurotransmitter systems: a review on the findings of molecular imaging studies. Psychopharmacology (Berl) 2016; 233:3473-501. [PMID: 27568200 PMCID: PMC5021729 DOI: 10.1007/s00213-016-4396-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 07/20/2016] [Indexed: 12/20/2022]
Abstract
RATIONALE Ecstasy is a commonly used psychoactive drug with 3,4-methylenedioxymethamphetamine (MDMA) as the main content. Importantly, it has been suggested that use of MDMA may be neurotoxic particularly for serotonergic (5-hydroxytryptamine (5-HT)) neurons. In the past decades, several molecular imaging studies examined directly in vivo the effects of ecstasy/MDMA on neurotransmitter systems. OBJECTIVES The objective of the present study is to review the effects of ecstasy/MDMA on neurotransmitter systems as assessed by molecular imaging studies in small animals, non-human primates and humans. METHODS A search in PubMed was performed. Eighty-eight articles were found on which inclusion and exclusion criteria were applied. RESULTS Thirty-three studies met the inclusion criteria; all were focused on the 5-HT or dopamine (DA) system. Importantly, 9 out of 11 of the animal studies that examined the effects of MDMA on 5-HT transporter (SERT) availability showed a significant loss of binding potential. In human studies, this was the case for 14 out of 16 studies, particularly in heavy users. In abstinent users, significant recovery of SERT binding was found over time. Most imaging studies in humans that focused on the DA system did not find any significant effect of ecstasy/MDMA use. CONCLUSIONS Preclinical and clinical molecular imaging studies on the effects of ecstasy/MDMA use/administration on neurotransmitter systems show quite consistent alterations of the 5-HT system. Particularly, in human studies, loss of SERT binding was observed in heavy ecstasy users, which might reflect 5-HT neurotoxicity, although alternative explanations (e.g. down-regulation of the SERT) cannot be excluded.
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Affiliation(s)
- Yosta Vegting
- Department of Nuclear Medicine, Academic Medical Center, University of Amsterdam, 1105, AZ, Amsterdam, The Netherlands.
| | - Liesbeth Reneman
- Department of Radiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands ,Brain Imaging Center, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Jan Booij
- Department of Nuclear Medicine, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands ,Brain Imaging Center, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
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16
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Shih JH, Ma KH, Chen CFF, Cheng CY, Pao LH, Weng SJ, Huang YS, Shiue CY, Yeh MK, Li IH. Evaluation of brain SERT occupancy by resveratrol against MDMA-induced neurobiological and behavioral changes in rats: A 4-[¹⁸F]-ADAM/small-animal PET study. Eur Neuropsychopharmacol 2016; 26:92-104. [PMID: 26612383 DOI: 10.1016/j.euroneuro.2015.11.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2015] [Revised: 10/23/2015] [Accepted: 11/08/2015] [Indexed: 12/17/2022]
Abstract
The misuse of 3,4-methylenedioxymethamphetamine (MDMA) has drawn a growing concern worldwide for its psychophysiological impacts on humans. MDMA abusers are often accompanied by long-term serotonergic neurotoxicity, which is associated with reduced density of cerebral serotonin transporters (SERT) and depressive disorders. Resveratrol (RSV) is a natural polyphenolic phytoalexin that has been known for its antidepressant and neuroprotective effects. However, biological targets of RSV as well as its neuroprotective effects against MDMA remained largely unknown. In this study, we examined binding potency of RSV and MDMA to SERT using small-animal positron emission tomography (PET) with the SERT radioligand, N,N-dimethyl-2-(2-amino-4-[(18)F]fluorophenylthio)benzylamine (4-[(18)F]-ADAM) and investigated the protection of RSV against the acute and long-term adverse effects of MDMA. We found that RSV exhibit binding potentials to SERT in vivo in a dose-dependent manner with variation among brain regions. When the MDMA-treated rats (10mg/kg, s.c.) were co-injected with RSV (20mg/kg, i.p.) twice daily for 4 consecutive days, MDMA-induced acute elevation in plasma corticosterone was significantly reduced. Further, 4-[(18)F]-ADAM PET imaging revealed that RSV protected against the MDMA-induced decrease in SERT availability in the midbrain and the thalamus 2 weeks following the co-treatment. The PET data were comparable to the observation from the forced swim test that RSV sufficiently ameliorated the depressive-like behaviors of the MDMA-treated rats. Together, these findings suggest that RSV is a potential antidepressant and may confer protection against neurobiological and behavioral changes induced by MDMA.
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Affiliation(s)
- Jui-Hu Shih
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan; Department of Pharmacy Practice, Tri-Service General Hospital, Taipei, Taiwan; School of Pharmacy, National Defense Medical Center, Taipei, Taiwan
| | - Kuo-Hsing Ma
- Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan
| | - Chien-Fu F Chen
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Cheng-Yi Cheng
- Department of Nuclear Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Li-Heng Pao
- School of Pharmacy, National Defense Medical Center, Taipei, Taiwan; Graduate Institute of Health-Industry Technology, Chang Gung University of Science and Technology, Taoyuan, Taiwan; Research Center for Industry of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan
| | - Shao-Ju Weng
- Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan
| | - Yuahn-Sieh Huang
- Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan
| | - Chyng-Yann Shiue
- Department of Nuclear Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Ming-Kung Yeh
- School of Pharmacy, National Defense Medical Center, Taipei, Taiwan; Ministry of Health and Welfare, Taiwan
| | - I-Hsun Li
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan; Department of Pharmacy Practice, Tri-Service General Hospital, Taipei, Taiwan; School of Pharmacy, National Defense Medical Center, Taipei, Taiwan.
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17
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Li IH, Ma KH, Kao TJ, Lin YY, Weng SJ, Yen TY, Chen LC, Huang YS. Involvement of autophagy upregulation in 3,4-methylenedioxymethamphetamine ('ecstasy')-induced serotonergic neurotoxicity. Neurotoxicology 2015; 52:114-26. [PMID: 26610922 DOI: 10.1016/j.neuro.2015.11.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 11/16/2015] [Accepted: 11/16/2015] [Indexed: 12/20/2022]
Abstract
It has been suggested that autophagy plays pathogenetic roles in cerebral ischemia, brain trauma, and neurodegenerative disorders. 3,4-Methylenedioxymethamphetamine (MDMA or ecstasy) is an illicit drug that causes long-term serotonergic neurotoxicity in the brain. Apoptosis and necrosis have been implicated in MDMA-induced neurotoxicity, but the role of autophagy in MDMA-elicited serotonergic toxicity has not been investigated. The present study aimed to examine the contribution of autophagy to neurotoxicity in serotonergic neurons in in vitro and in vivo animal models challenged with MDMA. Here, we demonstrated that in cultured rat serotonergic neurons, MDMA exposure induced LC3B-densely stained autophagosome formation, accompanying by a decrease in neurite outgrowth. Autophagy inhibitor 3-methyladenine (3-MA) significantly attenuated MDMA-induced autophagosome accumulation, and ameliorated MDMA-triggered serotonergic neurite damage and neuron death. In contrast, enhanced autophagy flux by rapamycin or impaired autophagosome clearance by bafilomycin A1 led to more autophagosome accumulation in serotonergic neurons and aggravated neurite degeneration. In addition, MDMA-induced autophagy activation in cultured serotonergic neurons might be mediated by serotonin transporter (SERT). In an in vivo animal model administered MDMA, neuroimaging showed that 3-MA protected the serotonin system against MDMA-induced downregulation of SERT evaluated by animal-PET with 4-[(18)F]-ADAM, a SERT radioligand. Taken together, our results demonstrated that MDMA triggers upregulation of autophagy in serotonergic neurons, which appears to be detrimental to neuronal growth.
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Affiliation(s)
- I-Hsun Li
- Department of Pharmacy Practice, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Kuo-Hsing Ma
- Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan
| | - Tzu-Jen Kao
- Graduate Institute of Neural Regenerative Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan; Center for Neurotrauma and Neuroregeneration, Taipei Medical University, Taipei, Taiwan
| | - Yang-Yi Lin
- Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan
| | - Shao-Ju Weng
- Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan
| | - Ting-Yin Yen
- Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan
| | - Lih-Chi Chen
- Department of Pharmacy, Taipei City Hospital, Taipei, Taiwan
| | - Yuahn-Sieh Huang
- Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan.
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18
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Huang YY, Cheng CY, Huang WS, Ma KH, Tseng TW, Chou TK, Huang Y, Shiue CY. Toxicity and radiation dosimetry studies of the serotonin transporter radioligand [(18) F]AFM in rats and monkeys. EJNMMI Res 2015; 4:71. [PMID: 26116128 PMCID: PMC4452647 DOI: 10.1186/s13550-014-0071-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 11/27/2014] [Indexed: 11/12/2022] Open
Abstract
Background [18 F]AFM is a potent and promising PET imaging agent for the serotonin transporter. We carried out an acute toxicity study in rats and radiation dosimetry in monkeys before the translation of the tracer to humans. Methods Single- and multiple-dose toxicity studies were conducted in Sprague–Dawley rats. Male and female rats were injected intravenously with AFM tartrate as a single dose of 98.7 or 987 μg/kg (592 or 5,920 μg/m2, 100× or 1,000× the proposed human dose of 8 μg, respectively) on day 1 or as five consecutive daily doses of 98.7 μg/kg/day (592 μg /m2/day, 100× human dose, total dose 493.5 μg/kg). PET/CT scans were performed in four Formosan rock monkeys (two males and two females, each monkey scanned twice) using a Siemens BIOGRAPH scanner. After injection of [18 F]AFM (88.5 ± 20.3 MBq), a low-dose CT scan and a series of eight whole-body PET scans in 3-D mode were performed. Time-activity data of source organs were used to calculate the residence times and estimate the absorbed radiation dose using the OLINDA/EXM software. Results In the rats, neither the single dose nor the five daily doses of AFM tartrate produced overt adverse effects clinically. In the monkeys, the radiation doses received by most organs ranged between 8.3 and 39.1 μGy/MBq. The osteogenic cells, red marrow, and lungs received the highest doses of 39.1, 35.4, and 35.1 μGy/MBq, respectively. The effective doses extrapolated to male and female adult humans were 18.0 and 18.3 μSv/MBq, respectively. Conclusions Toxicity studies in Sprague–Dawley rats and radiation dosimetry studies in Formosa rock monkeys suggest that [18 F]AFM is safe for use in human PET imaging studies. Trial registration IACUC-12-200.
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Affiliation(s)
- Ya-Yao Huang
- PET Center, Department of Nuclear Medicine, Tri-Service General Hospital, 325 Sec. 2, Cheng-Kung Road, Taipei, 114, Taiwan,
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19
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Chiu CH, Li IH, Weng SJ, Huang YS, Wu SC, Chou TK, Huang WS, Liao MH, Shiue CY, Cheng CY, Ma KH. PET Imaging of Serotonin Transporters With 4-[(18)F]-ADAM in a Parkinsonian Rat Model With Porcine Neural Xenografts. Cell Transplant 2015; 25:301-11. [PMID: 25994923 DOI: 10.3727/096368915x688236] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative disease characterized by a loss of dopaminergic neurons in the nigrostriatal pathway. Apart from effective strategies to halt the underlying neuronal degeneration, cell replacement now offers novel prospects for PD therapy. Porcine embryonic neural tissue has been considered an alternative source to human fetal grafts in neurodegenerative disorders because its use avoids major practical and ethical issues. This study was undertaken to evaluate the effects of embryonic day 27 (E27) porcine mesencephalic tissue transplantation in a PD rat model using animal positron emission tomography (PET) coupled with 4-[(18)F]-ADAM, a serotonin transporter (SERT) imaging agent. The parkinsonian rat was induced by injecting 6-hydroxydopamine into the medial forebrain bundle (MFB) of the right nigrostriatal pathway. The apomorphine-induced rotation behavioral test and 4-[(18)F]-ADAM/animal PET scanning were carried out following 6-OHDA lesioning. At the second week following 6-OHDA lesioning, the parkinsonian rat rotates substantially on apomorphine-induced contralateral turning. In addition, the mean striatal-specific uptake ratio (SUR) of 4-[(18)F]-ADAM decreased by 44%. After transplantation, the number of drug-induced rotations decreased markedly, and the mean SUR of 4-[(18)F]-ADAM and the level of SERT immunoreactivity (SERT-ir) in striatum were partially restored. The mean SUR level was restored to 71% compared to that for the contralateral intact side, which together with the abundant survival of tyrosine hydroxylase (TH) neurons accounted for functional recovery at the fourth week postgraft. In regard to the extent of donor-derived cells, we found the neurons of the xenografts from E27 transgenic pigs harboring red fluorescent protein (RFP) localized with TH-ir cells and SERT-ir in the grafted area. Thus, transplanted E27 porcine mesencephalic tissue may restore dopaminergic and serotonergic systems in the parkinsonian rat. The 4-[(18)F]-ADAM/animal PET can be used to detect serotonergic neuron loss in PD and monitor the efficacy of therapy.
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Affiliation(s)
- Chuang-Hsin Chiu
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
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20
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Yeh YW, Ho PS, Chen CY, Kuo SC, Liang CS, Ma KH, Shiue CY, Huang WS, Cheng CY, Wang TY, Lu RB, Huang SY. Incongruent reduction of serotonin transporter associated with suicide attempts in patients with major depressive disorder: a positron emission tomography study with 4-[18F]-ADAM. Int J Neuropsychopharmacol 2015; 18:pyu065. [PMID: 25522405 PMCID: PMC4360239 DOI: 10.1093/ijnp/pyu065] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Much evidence supports the role of the serotonin transporter (SERT) in the pathophysiology and pharmacotherapy of major depressive disorder (MDD) and suicidal behaviors. METHODS In this study, we recruited 17 antidepressant-naïve patients with MDD and 17 age- and gender-matched healthy controls. SERT availability was measured in vivo with N,N-dimethyl-2-(2-amino-4-[(18)F]fluorophenylthio)benzylamine (4-[(18)F]-ADAM) positron emission tomography (PET) imaging. The 21-item Hamilton Depression Rating Scale (HDRS) and Beck Scale for Suicide Ideation were used to assess the severity of depression and the intent of suicide ideation prior to PET imaging. All subjects with MDD were in a current state of depression with HDRS scores ≧18. Subjects who attempted suicide within two weeks of the study onset were recruited in the depressed suicidal group (n = 8). Subjects with MDD who denied any prior suicide attempt were recruited into the depressed non-suicidal group (n = 9). RESULTS A significant reduction of SERT availability in the midbrain, thalamus, and striatum was noted in the MDD group relative to the control group (Bonferroni-adjusted p-value < 0.05). Moreover, this effect was more pronounced in the depressed suicidal group compared to the control group (Bonferroni-adjusted p-value < 0.01). Relative to both the depressed non-suicidal and control groups, the depressed suicidal group showed an increased prefrontal cortex (PFC)/midbrain SERT binding ratio (Bonferroni-adjusted p-value < 0.01). CONCLUSIONS This study suggests an incongruent reduction of PFC SERT binding relative to the midbrain might discriminate between depressed suicide attempters and non-attempters in patients with MDD and may be involved in the pathophysiology of suicide behaviors.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - San-Yuan Huang
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan (Drs Yeh, Chen, Kuo, and S-Y Huang); Department of Psychiatry, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan (Drs Yeh, Chen, Kuo, Liang, and S-Y Huang); Department of Psychiatry, Beitou Branch, Tri-Service General Hospital, Taipei, Taiwan (Drs Ho and Liang); Department of Biology & Anatomy, National Defense Medical Center, Taipei, Taiwan (Prof Ma); Department of Nuclear Medicine Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan (Prof Shiue, Drs W-S Huang and Cheng); Department of Nuclear Medicine, Changhua Christian Hospital, Changhua, Taiwan (Dr W-S Huang); Department of Psychiatry, Tainan Hospital, Department of Health, Executive Yuan, Tainan, Taiwan (Dr Wang); Department of Psychiatry, National Cheng Kung University, Tainan, Taiwan (Dr Lu).
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21
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Zhu L, Li G, Choi SR, Plössl K, Chan P, Qiao H, Zha Z, Kung HF. An improved preparation of [18F]FPBM: A potential serotonin transporter (SERT) imaging agent. Nucl Med Biol 2013; 40:974-9. [DOI: 10.1016/j.nucmedbio.2013.08.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Accepted: 08/04/2013] [Indexed: 10/26/2022]
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22
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Lemoine L, Lieberman BP, Ploessl K, Zheng P, Kung HF. Characterization of FlipIDAM as a SERT-selective SPECT imaging agent. Nucl Med Biol 2013; 40:879-86. [PMID: 23856117 DOI: 10.1016/j.nucmedbio.2013.06.001] [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: 08/17/2012] [Revised: 05/23/2013] [Accepted: 06/04/2013] [Indexed: 11/15/2022]
Abstract
INTRODUCTION Biological evaluation of ([(125)I]4), a new single-photon emission computed tomography (SPECT) radioligand for imaging the serotonin transporter (SERT) which displayed improved in vivo kinetics for mapping SERT binding sites in the brain. METHODS In vitro binding studies of [(125)I]4 were performed with membrane homogenates of LLC-PK1 cells stably transfected and overexpressing one of the monoamine transporter (SERT, DAT or NET) and rat cortical homogenates. Biodistribution and ex vivo autoradiography studies were carried out in rats. In vivo competition experiments were evaluated to determine the SERT selectivity of [(125)I]4 vs. ([(125)I]1). RESULTS In vitro binding studies of 4 showed excellent binding affinity (Ki,SERT=0.90 ± 0.05 nM) and excellent selectivity over the other monoamine transporters (100 fold and >4000 fold for NET and DAT respectively). Scatchard analysis of saturation binding of [(125)I]4 to rat cortical homogenates gave a Kd value of 0.5 ± 0.09 nM and a Bmax value of 801.4 ± 58.08 fmol/mg protein. The biodistribution study showed rapid high brain uptake (3.09 ± 0.11% dose/organ at 2 min) and a good target to non-target ratio (hypothalamus to cerebellum) at 30 min (2.62) compared to [(125)I]1 (2.19). Ex vivo autoradiography showed that FlipIDAM localizes in accordance with SERT distribution patterns in the brain. In vivo and ex vivo competition experiments with specific and non-specific SERT compounds also showed that [(125)I]4 binds specifically to SERT rich regions. CONCLUSIONS The biological evaluation of [(125)I]4 demonstrates that [(123)I]4 would be a good candidate for SPECT imaging of SERT.
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Affiliation(s)
- Laetitia Lemoine
- Department of Radiology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104
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23
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Kang HH, Wang CH, Chen HC, Li IH, Cheng CY, Liu RS, Huang WS, Shiue CY, Ma KH. Investigating the effects of noise-induced hearing loss on serotonin transporters in rat brain using 4-[18F]-ADAM/small animal PET. Neuroimage 2013; 75:262-269. [DOI: 10.1016/j.neuroimage.2012.06.049] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Revised: 06/08/2012] [Accepted: 06/26/2012] [Indexed: 01/10/2023] Open
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Stehouwer JS, Goodman MM. 11C and18F PET radioligands for the serotonin transporter (SERT). J Labelled Comp Radiopharm 2013; 56:114-9. [DOI: 10.1002/jlcr.3011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 10/29/2012] [Accepted: 11/20/2012] [Indexed: 01/03/2023]
Affiliation(s)
- Jeffrey S. Stehouwer
- Center for Systems Imaging, Department of Radiology and Imaging Sciences; Emory University; Atlanta; GA; USA
| | - Mark M. Goodman
- Center for Systems Imaging, Department of Radiology and Imaging Sciences; Emory University; Atlanta; GA; USA
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25
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Zheng P, Lieberman BP, Ploessl K, Lemoine L, Miller S, Kung HF. A new single-photon emission computed tomography (SPECT) imaging agent for serotonin transporters: [(125)I]Flip-IDAM, (2-((2-((dimethylamino)methyl)-4-iodophenyl)thio)phenyl)methanol. Bioorg Med Chem Lett 2013; 23:869-72. [PMID: 23265880 DOI: 10.1016/j.bmcl.2012.11.043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Revised: 11/07/2012] [Accepted: 11/12/2012] [Indexed: 11/18/2022]
Abstract
New ligands for in vivo brain imaging of serotonin transporter (SERT) with single photon emission tomography (SPECT) were prepared and evaluated. An efficient synthesis and radiolabeling of a biphenylthiol, FLIP-IDAM, 4, was accomplished. The affinity of FLIP-IDAM was evaluated by an in vitro inhibitory binding assay using [(125)I]-IDAM as radioligand in rat brain tissue homogenates (K(i) = 0.03 nM). New [(125)I]Flip-IDAM exhibited excellent binding affinity to SERT binding sites with a high hypothalamus to cerebellum ratio of 4 at 30 min post iv injection. The faster in vivo kinetics for brain uptake and a rapid washout from non-specific regions provide excellent signal to noise ratio. This new agent, when labeled with (123)I, may be a useful imaging agent for mapping SERT binding sites in the human brain.
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Affiliation(s)
- Pinguan Zheng
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
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Weng SJ, Shiue CY, Huang WS, Cheng CY, Huang SY, Li IH, Tao CC, Chou TK, Liao MH, Chang YP, Ma KH. PET imaging of serotonin transporters with 4-[18F]-ADAM in a Parkinsonian rat model. Cell Transplant 2012; 22:1295-305. [PMID: 23127756 DOI: 10.3727/096368912x658683] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
This study was undertaken to address the effects of fetal mesencephalic tissue transplantation on the serotonin system in a rat model of Parkinson's disease (PD) while also investigating the usefulness of 4-[18F]-ADAM (a serotonin transporter imaging agent) coupled with micro-PET for imaging serotonin transporters (SERTs). A PD model was induced by unilateral injection of 6-hydroxydopamine (6-OHDA) into the right medial forebrain bundle of the nigrostriatal pathway, while cell transplantation was performed via intrastriatal injection of mesencephalic brain tissue dissected from embryonic (E14) rats. The 4-[18F]-ADAM/micro-PET scanning was performed following both 6-OHDA lesioning and transplantation. Immunohistochemistry (IHC) studies were also performed following the final PET scan, and the results were compared to show a 17-43% decrease in the specific uptake ratio (SUR) and a 23-52% decrease in serotonin transporter immunoreactivity (SERT-ir) within various brain regions on the lesioned side. The number of methamphetamine-induced rotations also decreased significantly at the 4th week postgraft. In addition, striatal SUR and the SERT-ir levels were restored to 77% and 83% 5 weeks postgraft. These results suggest that Parkinson's disease also affects the serotonergic system, while both the dopaminergic and serotonergic systems can be partially restored in a rat model of PD after E14 mesencephalic tissue transplantation. In addition, we have also determined that 4-[18F]-ADAM/micro-PET can be used to detect serotonergic neuron loss, monitor the progress of Parkinson's disease, and oversee the effectiveness of therapy.
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Affiliation(s)
- Shao-Ju Weng
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
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Huang WS, Huang SY, Ho PS, Ma KH, Huang YY, Yeh CB, Liu RS, Cheng CY, Shiue CY. PET imaging of the brain serotonin transporters (SERT) with N,N-dimethyl-2-(2-amino-4-[18F]fluorophenylthio)benzylamine (4-[18F]-ADAM) in humans: a preliminary study. Eur J Nucl Med Mol Imaging 2012; 40:115-24. [PMID: 23053324 DOI: 10.1007/s00259-012-2250-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Accepted: 09/03/2012] [Indexed: 10/27/2022]
Abstract
PURPOSE The aim of this study was to assess the feasibility of using 4-[(18)F]-ADAM as a brain SERT imaging agent in humans. METHODS Enrolled in the study were 19 healthy Taiwanese subjects (11 men, 8 women; age 33 ± 9 years). The PET data were semiquantitatively analyzed and expressed as specific uptake ratios (SUR) and distribution volume ratios (DVR) using the software package PMOD. The SUR and DVR of 4-[(18)F]-ADAM in the raphe nucleus (RN), midbrain (MB), thalamus (TH), striatum (STR) and prefrontal cortex (PFC) were determined using the cerebellum (CB) as the reference region. RESULTS 4-[(18)F]-ADAM bound to known SERT-rich regions in human brain. The order of the regional brain uptake was MB (RN) > TH > STR > PFC > CB. The DVR (n = 4, t* = 60 min) in the RN, TH, STR and PFC were 3.00 ± 0.50, 2.25 ± 0.45, 2.05 ± 0.31 and 1.40 ± 0.13, respectively. The optimal time for imaging brain SERT with 4-[(18)F]-ADAM was 120-140 min after injection. At the optimal imaging time, the SURs (n = 15) in the MB, TH, STR, and PFC were 2.25 ± 0.20, 2.28 ± 0.20, 2.12 ± 0.18 and 1.47 ± 0.14, respectively. There were no significant differences in SERT availability between men and women (p < 0.05). CONCLUSION The results of this study showed that 4-[(18)F]-ADAM was safe for human studies and its distribution in human brain appeared to correlate well with the known distribution of SERT in the human brain. In addition, it had high specific binding and a reasonable optimal time for imaging brain SERT in humans. Thus, 4-[(18)F]-ADAM may be feasible for assessing the status of brain SERT in humans.
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Affiliation(s)
- Wen-Sheng Huang
- Department of Nuclear Medicine, PET Center, Tri-Service General Hospital, 325 Sec. 2 Cheng-Kung Rd, Neihu, Taipei, Taiwan
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