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Hart XM, Gründer G, Ansermot N, Conca A, Corruble E, Crettol S, Cumming P, Hefner G, Frajerman A, Howes O, Jukic M, Kim E, Kim S, Manisalco I, Moriguchi S, Müller DJ, Nakajima S, Osugo M, Paulzen M, Ruhe HG, Scherf-Clavel M, Schoretsanitis G, Serretti A, Spina E, Spigset O, Steimer W, Süzen HS, Uchida H, Unterecker S, Vandenberghe F, Verstuyft C, Zernig G, Hiemke C, Eap CB. Optimisation of pharmacotherapy in psychiatry through therapeutic drug monitoring, molecular brain imaging and pharmacogenetic tests: focus on antipsychotics. World J Biol Psychiatry 2024:1-123. [PMID: 38913780 DOI: 10.1080/15622975.2024.2366235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2023] [Accepted: 06/06/2024] [Indexed: 06/26/2024]
Abstract
BACKGROUND For psychotic disorders (i.e. schizophrenia), pharmacotherapy plays a key role in controlling acute and long-term symptoms. To find the optimal individual dose and dosage strategy, specialized tools are used. Three tools have been proven useful to personalize drug treatments: therapeutic drug monitoring (TDM) of drug levels, pharmacogenetic testing (PG), and molecular neuroimaging. METHODS In these Guidelines, we provide an in-depth review of pharmacokinetics, pharmacodynamics, and pharmacogenetics for 50 antipsychotics. Over 30 international experts in psychiatry selected studies that have measured drug concentrations in the blood (TDM), gene polymorphisms of enzymes involved in drug metabolism, or receptor/transporter occupancies in the brain (positron emission tomography (PET)). RESULTS Study results strongly support the use of TDM and the cytochrome P450 (CYP) genotyping and/or phenotyping to guide drug therapies. Evidence-based target ranges are available for titrating drug doses that are often supported by PET findings. CONCLUSION All three tools discussed in these Guidelines are essential for drug treatment. TDM goes well beyond typical indications such as unclear compliance and polypharmacy. Despite its enormous potential to optimize treatment effects, minimize side effects and ultimately reduce the global burden of diseases, personalized drug treatment has not yet become the standard of care in psychiatry.
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Affiliation(s)
- X M Hart
- Central Institute of Mental Health, Department of Molecular Neuroimaging, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan
| | - G Gründer
- Central Institute of Mental Health, Department of Molecular Neuroimaging, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
- German Center for Mental Health (DZPG), partner site Mannheim - Heidelberg - Ulm
| | - N Ansermot
- Unit of Pharmacogenetics and Clinical Psychopharmacology, Center for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital, Prilly, Switzerland
| | - A Conca
- Dipartimento di Psichiatria, Comprensorio Sanitario di Bolzano, Bolzano, Italy
| | - E Corruble
- Université Paris-Saclay, AP-HP, Service Hospitalo-Universitaire de Psychiatrie, Hôpital de Bicêtre
- Equipe MOODS, Inserm U1018, CESP (Centre de Recherche en Epidémiologie et Sante des Populations), Le Kremlin-Bicêtre, France
| | - S Crettol
- Unit of Pharmacogenetics and Clinical Psychopharmacology, Centre for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital and University of Lausanne, Prilly, Switzerland
| | - P Cumming
- Department of Nuclear Medicine, Bern University Hospital, Bern, Switzerland
- School of Psychology and Counseling, Queensland University of Technology, Brisbane, Australia
| | - G Hefner
- Vitos Clinic for Forensic Psychiatry, Forensic Psychiatry, Eltville, Germany
| | - A Frajerman
- Université Paris-Saclay, AP-HP, Service Hospitalo-Universitaire de Psychiatrie, Hôpital de Bicêtre
- Equipe MOODS, Inserm U1018, CESP (Centre de Recherche en Epidémiologie et Sante des Populations), Le Kremlin-Bicêtre, France
| | - O Howes
- Department of Psychosis Studies, IoPPN, King's College London, De Crespigny Park, London, SE5 8AF, UK
- Institute of Clinical Sciences (ICS), Faculty of Medicine, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - M Jukic
- Department of Physiology, Faculty of Pharmacy, University of Belgrade, Belgrade, Serbia and Pharmacogenetics Section, Department of Physiology and Pharmacology, Karolinska Institutet, Solna, Sweden
| | - E Kim
- Department of Psychiatry, Seoul National University College of Medicine, Republic of Korea
| | - S Kim
- Department of Neuropsychiatry, Seoul National University Bundang Hospital, Republic of Korea
| | - I Manisalco
- Dipartimento di Psichiatria, Comprensorio Sanitario di Bolzano, Bolzano, Italy
| | - S Moriguchi
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan
| | - D J Müller
- Department of Psychiatry, Psychosomatics and Psychotherapy, Center of Mental Health, University Hospital of Würzburg, Würzburg, Germany
- Pharmacogenetics Research Clinic, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada, and Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - S Nakajima
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan
| | - M Osugo
- Department of Psychosis Studies, IoPPN, King's College London, De Crespigny Park, London, SE5 8AF, UK
- Institute of Clinical Sciences (ICS), Faculty of Medicine, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - M Paulzen
- Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University
- JARA - Translational Brain Medicine, Aachen, Germany; Alexianer Center for Mental Health, Aachen, Germany
| | - H G Ruhe
- Department of psychiatry, Radboudumc, Nijmegen, Netherlands; Donders Institute for Brain, Cognition and Behavior, Radboud University, Nijmegen, Netherlands
| | - M Scherf-Clavel
- Department of Psychiatry, Psychosomatics and Psychotherapy, Center of Mental Health, University Hospital of Würzburg, Würzburg, Germany
| | - G Schoretsanitis
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, 8032 Zurich, Switzerland
| | - A Serretti
- Department of Medicine and Surgery, Kore University of Enna, Italy
| | - E Spina
- Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy
| | - O Spigset
- Department of Clinical Pharmacology, St. Olav University Hospital, Trondheim, Norway, and Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - W Steimer
- Institute of Clinical Chemistry and Pathobiochemistry, Technical University Munich, Munich, Germany
| | - H S Süzen
- Department of Pharmaceutic Toxicology, Faculty of Pharmacy, Ankara University, Ankara, Turkey
| | - H Uchida
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan
| | - S Unterecker
- Department of Psychiatry, Psychosomatics and Psychotherapy, Center of Mental Health, University Hospital of Würzburg, Würzburg, Germany
| | - F Vandenberghe
- Unit of Pharmacogenetics and Clinical Psychopharmacology, Centre for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital, Prilly, Switzerland
| | - C Verstuyft
- Department of Molecular Genetics, Pharmacogenetics and Hormonology Bicêtre University Hospital Paris-Saclay, Assistance Publique-Hôpitaux de Paris, Le Kremlin Bicêtre, F-94275, France
- CESP, MOODS Team, INSERM UMR 1018, Medicine Faculty, Paris-Saclay University, Le Kremlin Bicêtre, France
| | - G Zernig
- Department of Pharmacology, Medical University Innsbruck; Private Practice for Psychotherapy and Court-Certified Witness, Hall in Tirol, Austria
| | - C Hiemke
- Department of Psychiatry and Psychotherapy and Institute of Clinical Chemistry and Laboratory Medicine, University Medical Center of Mainz, Germany
| | - C B Eap
- Unit of Pharmacogenetics and Clinical Psychopharmacology, Department of Psychiatry, Centre for Psychiatric Neuroscience, Lausanne University Hospital, University of Lausanne, 1008 Prilly, Switzerland
- School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, Geneva, Switzerland
- Center for Research and Innovation in Clinical Pharmaceutical Sciences, University of Lausanne, Lausanne, Switzerland
- Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, University of Lausanne, Lausanne, Switzerland
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Lombardozzi G, Trovini G, Amici E, Kotzalidis GD, Perrini F, Giovanetti V, Di Giovanni A, De Filippis S. Brexpiprazole in patients with schizophrenia with or without substance use disorder: an observational study. Front Psychiatry 2023; 14:1321233. [PMID: 38111619 PMCID: PMC10725927 DOI: 10.3389/fpsyt.2023.1321233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 11/13/2023] [Indexed: 12/20/2023] Open
Abstract
Background Partial dopamine D2 receptor agonists are used for psychotic symptoms in adults with schizophrenia spectrum disorders. Recently, interest surged for partial dopamine D2 receptor agonists in substance use disorders (SUDs). Since it is believed that SUDs decrease the efficacy of pharmacotherapy of underlying psychiatric disorders, we tested the efficacy of the partial D2 agonist brexpiprazole in patients with schizophrenia who were either comorbid with a SUD (SUD group) or not comorbid (non-SUD) to assess treatment response and the effect of brexpiprazole on substance craving in SUD. Methods We included patients with DSM-5/DSM-5-TR schizophrenia (using SCID-5-CV) aged 18-66 years with either comorbid SUD or non-SUD to treat with brexpiprazole 4 mg/day for 6 months during February-October 2022. Patients were assessed with the Clinical Global Impressions-Severity (CGI-S) scale, the 24-item Brief Psychiatric Rating Scale (BPRS), and the Positive And Negative Syndrome Scale (PANSS) at baseline, weekly for the first 2 months and monthly for the next four. Furthermore, we assessed substance craving in SUD with a visual analog scale for craving (VAScrav) at the same timepoints. Results The total sample was 86 (85 analysable) 18- to 64-year-old (mean 39.32 ± 14.09) patients with schizophrenia [51 men (59.3%) and 35 women (40.7%)], of whom 48 SUD (55.8%) (37 men and 11 women) and 38 non-SUD (44.2%) (14 men and 24 women). No serious or persistent adverse events developed over the study period, but one patient dropped out for subjective akathisia. Results indicated the main effects of time with improvements over the course of the study for CGI-S, BPRS, and PANSS in both SUD and non-SUD groups and the entire sample, and for VAScrav in SUD. Brexpiprazole was associated with similar significant improvements in both groups at the 6 month endpoint compared to baseline. Conclusion Treatment with brexpiprazole for 6 months improved psychotic symptoms in patients with schizophrenia, independently from whether they belonged to the SUD or the non-SUD group; hence, SUD comorbidity did not confer treatment resistance to brexpiprazole. Furthermore, in the SUD group, we observed reduced substance craving.
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Affiliation(s)
- Ginevra Lombardozzi
- Villa Von Siebenthal Neuropsychiatric Hospital and Clinic, Genzano di Roma, Italy
| | - Giada Trovini
- Villa Von Siebenthal Neuropsychiatric Hospital and Clinic, Genzano di Roma, Italy
| | - Emanuela Amici
- Villa Von Siebenthal Neuropsychiatric Hospital and Clinic, Genzano di Roma, Italy
| | - Georgios D. Kotzalidis
- Villa Von Siebenthal Neuropsychiatric Hospital and Clinic, Genzano di Roma, Italy
- NESMOS Department, Faculty of Medicine and Psychology, Sant'Andrea Hospital, Sapienza University, Rome, Italy
- Department of Neuroscience, Section of Psychiatry, Fondazione Policlinico Universitario Agostino Gemelli IRCSS, Rome, Italy
- Centro Lucio Bini, Rome, Italy
| | | | - Valeria Giovanetti
- Villa Von Siebenthal Neuropsychiatric Hospital and Clinic, Genzano di Roma, Italy
| | | | - Sergio De Filippis
- Villa Von Siebenthal Neuropsychiatric Hospital and Clinic, Genzano di Roma, Italy
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Yamasaki F, Kanahara N, Nakata Y, Koyoshi S, Yanagisawa Y, Saito T, Oiwa T, Kogure M, Sasaki T, Yoshida T, Kimura H, Iyo M. Can brexpiprazole be switched safely in patients with schizophrenia and dopamine supersensitivity psychosis? A retrospective analysis in a real-world clinical practice. J Psychopharmacol 2023; 37:992-1002. [PMID: 37395368 DOI: 10.1177/02698811231177268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
BACKGROUND Several studies have reported that a switch to the dopamine partial agonist (DPA) aripiprazole (ARP), especially when the switch is abrupt, is likely to fail and sometimes worsen psychosis in schizophrenia patients already under high-dose antipsychotic treatment. Such a switching failure is speculated to be related to be the dopamine supersensitivity state. The risks of switching to the DPA brexpiprazole (BREX) have not been reported. AIMS AND METHODS We retrospectively analyzed the cases of 106 patients with schizophrenia to identify any factors related to the success or failure of switching to BREX. RESULTS The comparison between the patients with dopamine supersensitivity psychosis (n = 44) and those without (n = 62) revealed no significant difference in the switching failure judged at the sixth week. A comparison of the patients with successful switching (n = 80) and those who failed (n = 26) revealed that patients with treatment-resistant schizophrenia (TRS) were significantly more likely to fail. A logistic regression analysis also revealed that patients with past failure of switching to ARP are likely to succeed in switching to BREX. The 2-year follow-up of the patients with successful switching to BREX suggested that the patients who were treated with BREX, even temporarily, experienced some improvement in their Global Assessment of Functioning and Clinical Global Impression-Severity scores. CONCLUSIONS Overall, the results indicate that patients with schizophrenia can be switched more safely to BREX compared to ARP. However, the failure of switching to BREX could be higher in patients with TRS, and thus, starting BREX treatment in refractory patients warrants careful monitoring.
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Affiliation(s)
- Fumiaki Yamasaki
- Department of Psychiatry, Chiba University Graduate School of Medicine, Chiba, Japan
- Department of Psychiatry, Douwa-kai Chiba Hospital, Funabashi, Japan
| | - Nobuhisa Kanahara
- Division of Medical Treatment and Rehabilitation, Chiba University Center for Forensic Mental Health, Chiba, Japan
- Department of Psychiatry, Shirayuri-kai Ichihara Tsuruoka Hospital, Ichihara, Japan
| | - Yusuke Nakata
- Department of Psychiatry, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Shinji Koyoshi
- Department of Psychiatry, Doujin-kai Kisarazu Hospital, Kisarazu, Japan
| | - Yuta Yanagisawa
- Department of Psychiatry, Chiba University Graduate School of Medicine, Chiba, Japan
- Department of Psychiatry, Gakuji-kai Kimura Hospital, Chiba, Japan
| | - Takeru Saito
- Department of Psychiatry, Naoki-kai Isogaya Hospital, Ichihara, Japan
| | - Takahiro Oiwa
- Department of Psychiatry, Naoki-kai Isogaya Hospital, Ichihara, Japan
| | - Masanobu Kogure
- Department of Psychiatry, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Tsuyoshi Sasaki
- Department of Psychiatry, Douwa-kai Chiba Hospital, Funabashi, Japan
- Department of Child Psychiatry, Chiba University Hospital, Chiba, Japan
| | - Taisuke Yoshida
- Department of Psychiatry, Doujin-kai Kisarazu Hospital, Kisarazu, Japan
| | - Hiroshi Kimura
- Department of Psychiatry, Chiba University Graduate School of Medicine, Chiba, Japan
- Department of Psychiatry, Gakuji-kai Kimura Hospital, Chiba, Japan
- Department of Psychiatry, School of Medicine, International University of Health and Welfare, Narita, Japan
| | - Masaomi Iyo
- Department of Psychiatry, Chiba University Graduate School of Medicine, Chiba, Japan
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4
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Taylor D, Chithiramohan R, Grewal J, Gupta A, Hansen L, Reynolds GP, Pappa S. Dopamine partial agonists: a discrete class of antipsychotics. Int J Psychiatry Clin Pract 2023; 27:272-284. [PMID: 36495086 DOI: 10.1080/13651501.2022.2151473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 11/04/2022] [Accepted: 11/08/2022] [Indexed: 12/14/2022]
Abstract
Worldwide, there are now three marketed dopamine D2 partial agonists: aripiprazole, brexpiprazole and cariprazine. These three drugs share a number of properties other than their action at D2 receptors. Pharmacologically, they are 5HT2 antagonists and D3 and 5HT1A partial agonists but with little or no alpha-adrenergic, anticholinergic or antihistaminic activity. They also share a long duration of action. Clinically, D2 partial agonists are effective antipsychotics and generally have useful antimanic and antidepressant activity. They are usually well tolerated, causing akathisia and insomnia only at the start of treatment, and are non-sedating. These drugs also share a very low risk of increased prolactin and of weight gain and accompanying metabolic effects. They may also have a relatively low risk of tardive dyskinesia. There is some evidence that they are preferred by patients to dopamine antagonists. Individual dopamineD2 partial agonists have much in common and as a group they differ importantly from dopamine D2 antagonists. Dopamine D2 partial agonists should be considered a distinct class of antipsychotics.Key pointsD2 partial agonists share many pharmacological and clinical propertiesD2 partial agonists differ in several important respects from D2 antagonistsD2 partial agonists should be considered a discrete class of antipsychotics.
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Affiliation(s)
- David Taylor
- Institute of Pharmaceutical Science, King's College London, London, UK
- Pharmacy Department, South London and Maudsley NHS Foundation Trust, London, UK
| | | | | | - Avirup Gupta
- South London and Maudsley NHS Foundation Trust, London, UK
| | - Lars Hansen
- Southampton University, Hartley Library B12, Southampton, UK
- Southern Health NHS Foundation Trust, Southampton, UK
| | - Gavin P Reynolds
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, UK
| | - Sofia Pappa
- Department of Brain Sciences, Imperial College London, London, UK
- West London NHS Trust, London, UK
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5
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Siafis S, Wu H, Wang D, Burschinski A, Nomura N, Takeuchi H, Schneider-Thoma J, Davis JM, Leucht S. Antipsychotic dose, dopamine D2 receptor occupancy and extrapyramidal side-effects: a systematic review and dose-response meta-analysis. Mol Psychiatry 2023; 28:3267-3277. [PMID: 37537284 PMCID: PMC10618092 DOI: 10.1038/s41380-023-02203-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 07/17/2023] [Accepted: 07/25/2023] [Indexed: 08/05/2023]
Abstract
Antipsychotic drugs differ in their propensity to cause extrapyramidal side-effects (EPS), but their dose-effects are unclear. Therefore, we conducted a systematic review and dose-response meta-analysis. We searched multiple electronic databases up to 20.02.2023 for fixed-dose studies investigating 16 second-generation antipsychotics and haloperidol (all formulations and administration routes) in adults with acute exacerbations of schizophrenia. The primary outcome was the number of participants receiving antiparkinsonian medication, and if not available, the number of participants with extrapyramidal side-effects (EPS) and the mean scores of EPS rating scales were used as proxies. The effect-size was odds ratio (ORs) compared with placebo. One-stage random-effects dose-response meta-analyses with restricted cubic splines were conducted to estimate the dose-response curves. We also examined the relationship between dopamine D2 receptor (D2R) occupancy and ORs by estimating occupancies from administrated doses. We included data from 110 studies with 382 dose arms (37193 participants). Most studies were short-term with median duration of 6 weeks (range 3-26 weeks). Almost all antipsychotics were associated with dose-dependent EPS with varied degrees and the maximum ORs ranged from OR = 1.57 95%CI [0.97, 2.56] for aripiprazole to OR = 7.56 95%CI [3.16, 18.08] for haloperidol at 30 mg/d. Exceptions were quetiapine and sertindole with negligible risks across all doses. There was very low quality of findings for cariprazine, iloperidone, and zotepine, and no data for clozapine. The D2R occupancy curves showed that the risk increased substantially when D2R occupancy exceeded 75-85%, except for D2R partial agonists that had smaller ORs albeit high D2R occupancies. In conclusion, we found that the risk of EPS increases with rising doses and differs substantially in magnitude among antipsychotics, yet exceptions were quetiapine and sertindole with negligible risks. Our data provided additional insights into the current D2R therapeutic window for EPS.
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Affiliation(s)
- Spyridon Siafis
- Department of Psychiatry and Psychotherapy, School of Medicine, Technical University of Munich, Munich, Germany.
| | - Hui Wu
- Department of Psychiatry and Psychotherapy, School of Medicine, Technical University of Munich, Munich, Germany
| | - Dongfang Wang
- Department of Psychiatry and Psychotherapy, School of Medicine, Technical University of Munich, Munich, Germany
| | - Angelika Burschinski
- Department of Psychiatry and Psychotherapy, School of Medicine, Technical University of Munich, Munich, Germany
| | - Nobuyuki Nomura
- Department of Psychiatry and Psychotherapy, School of Medicine, Technical University of Munich, Munich, Germany
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan
| | - Hiroyoshi Takeuchi
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan
| | - Johannes Schneider-Thoma
- Department of Psychiatry and Psychotherapy, School of Medicine, Technical University of Munich, Munich, Germany
| | - John M Davis
- Psychiatric Institute, University of Illinois at Chicago, Chicago, IL, USA
- Maryland Psychiatric Research Center, Baltimore, MD, USA
| | - Stefan Leucht
- Department of Psychiatry and Psychotherapy, School of Medicine, Technical University of Munich, Munich, Germany
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Abstract
Over the past decade, psychedelic compounds have emerged as potentially transformative therapeutics for a variety of intractable neuropsychiatric conditions. However, historically most of the basic science has utilized these compounds as probes to interrogate various endogenous neurotransmitter systems-mainly the serotonin 5-HT2A receptor. With the renewed interest in utilizing these compounds as therapeutics and the explosion in clinical trials, psychedelics have been purported to treat many neuropsychiatric disorders, including depression, cluster headaches, migraines, anxiety, and obsessive-compulsive disorder. It is therefore imperative to understand the biology and pharmacology behind their therapeutic mechanisms as well as expose any potential pitfalls in their widespread use as treatments. This review covers the latest advances in understanding the biological mechanisms, the newest efforts in drug discovery, and potential pitfalls when it comes to utilizing this class of compounds as emerging therapeutics.
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Affiliation(s)
- Bryan L Roth
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill
| | - Ryan H Gumpper
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill
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7
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Lopresti BJ, Royse SK, Mathis CA, Tollefson SA, Narendran R. Beyond monoamines: I. Novel targets and radiotracers for Positron emission tomography imaging in psychiatric disorders. J Neurochem 2023; 164:364-400. [PMID: 35536762 DOI: 10.1111/jnc.15615] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 04/05/2022] [Accepted: 04/06/2022] [Indexed: 10/18/2022]
Abstract
With the emergence of positron emission tomography (PET) in the late 1970s, psychiatry had access to a tool capable of non-invasive assessment of human brain function. Early applications in psychiatry focused on identifying characteristic brain blood flow and metabolic derangements using radiotracers such as [15 O]H2 O and [18 F]FDG. Despite the success of these techniques, it became apparent that more specific probes were needed to understand the neurochemical bases of psychiatric disorders. The first neurochemical PET imaging probes targeted sites of action of neuroleptic (dopamine D2 receptors) and psychoactive (serotonin receptors) drugs. Based on the centrality of monoamine dysfunction in psychiatric disorders and the measured success of monoamine-enhancing drugs in treating them, the next 30 years witnessed the development of an armamentarium of PET radiopharmaceuticals and imaging methodologies for studying monoamines. Continued development of monoamine-enhancing drugs over this time however was less successful, realizing only modest gains in efficacy and tolerability. As patent protection for many widely prescribed and profitable psychiatric drugs lapsed, drug development pipelines shifted away from monoamines in search of novel targets with the promises of improved efficacy, or abandoned altogether. Over this period, PET radiopharmaceutical development activities closely paralleled drug development priorities resulting in the development of new PET imaging agents for non-monoamine targets. Part one of this review will briefly survey novel PET imaging targets with relevance to the field of psychiatry, which include the metabotropic glutamate receptor type 5 (mGluR5), purinergic P2 X7 receptor, type 1 cannabinoid receptor (CB1 ), phosphodiesterase 10A (PDE10A), and describe radiotracers developed for these and other targets that have matured to human subject investigations. Current limitations of the targets and techniques will also be discussed.
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Affiliation(s)
- Brian J Lopresti
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Sarah K Royse
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Chester A Mathis
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Savannah A Tollefson
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Rajesh Narendran
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.,Departments of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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8
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Courault P, Lancelot S, Costes N, Colom M, Le Bars D, Redoute J, Gobert F, Dailler F, Isal S, Iecker T, Newman-Tancredi A, Merida I, Zimmer L. [ 18F]F13640: a selective agonist PET radiopharmaceutical for imaging functional 5-HT 1A receptors in humans. Eur J Nucl Med Mol Imaging 2023; 50:1651-1664. [PMID: 36656363 PMCID: PMC10119077 DOI: 10.1007/s00259-022-06103-1] [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: 05/23/2022] [Accepted: 12/27/2022] [Indexed: 01/20/2023]
Abstract
PURPOSE F13640 (a.k.a. befiradol, NLX-112) is a highly selective 5-HT1A receptor ligand that was selected as a PET radiopharmaceutical-candidate based on animal studies. Due to its high efficacy agonist properties, [18F]F13640 binds preferentially to functional 5-HT1A receptors, which are coupled to intracellular G-proteins. Here, we characterize brain labeling of 5-HT1A receptors by [18F]F13640 in humans and describe a simplified model for its quantification. METHODS PET/CT and PET-MRI scans were conducted in a total of 13 healthy male volunteers (29 ± 9 years old), with arterial input functions (AIF) (n = 9) and test-retest protocol (n = 8). Several kinetic models were compared (one tissue compartment model, two-tissue compartment model, and Logan); two models with reference region were also evaluated: simplified reference tissue model (SRTM) and the logan reference model (LREF). RESULTS [18F]F13640 showed high uptake values in raphe nuclei and cortical regions. SRTM and LREF models showed a very high correlation with kinetic models using AIF. As concerns test-retest parameters and the prolonged binding kinetics of [18F]F13640, better reproducibility, and reliability were found with the LREF method. Cerebellum white matter and frontal lobe white matter stand out as suitable reference regions. CONCLUSION The favorable brain labeling and kinetic profile of [18F]F13640, its high receptor specificity and its high efficacy agonist properties open new perspectives for studying functionally active 5-HT1A receptors, unlike previous radiopharmaceuticals that act as antagonists. [18F]F13640's kinetic properties allow injection outside of the PET scanner with delayed acquisitions, facilitating the design of innovative longitudinal protocols in neurology and psychiatry. TRIAL REGISTRATION Trial Registration EudraCT 2017-002,722-21.
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Affiliation(s)
- Pierre Courault
- Université Claude Bernard Lyon 1, CNRS, INSERM, Lyon Neuroscience Research Center, Lyon, France.,Hospices Civils de Lyon (HCL), Lyon, France
| | - Sophie Lancelot
- Université Claude Bernard Lyon 1, CNRS, INSERM, Lyon Neuroscience Research Center, Lyon, France.,Hospices Civils de Lyon (HCL), Lyon, France.,CERMEP, Bron, France
| | - Nicolas Costes
- Université Claude Bernard Lyon 1, CNRS, INSERM, Lyon Neuroscience Research Center, Lyon, France.,CERMEP, Bron, France
| | | | - Didier Le Bars
- Hospices Civils de Lyon (HCL), Lyon, France.,CERMEP, Bron, France
| | | | - Florent Gobert
- Université Claude Bernard Lyon 1, CNRS, INSERM, Lyon Neuroscience Research Center, Lyon, France.,Hospices Civils de Lyon (HCL), Lyon, France
| | | | - Sibel Isal
- Hospices Civils de Lyon (HCL), Lyon, France
| | | | | | | | - Luc Zimmer
- Université Claude Bernard Lyon 1, CNRS, INSERM, Lyon Neuroscience Research Center, Lyon, France. .,Hospices Civils de Lyon (HCL), Lyon, France. .,CERMEP, Bron, France.
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9
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Vasiliu O. The pharmacogenetics of the new-generation antipsychotics - A scoping review focused on patients with severe psychiatric disorders. Front Psychiatry 2023; 14:1124796. [PMID: 36873203 PMCID: PMC9978195 DOI: 10.3389/fpsyt.2023.1124796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 01/30/2023] [Indexed: 02/18/2023] Open
Abstract
Exploring the possible correlations between gene variations and the clinical effects of the new-generation antipsychotics is considered essential in the framework of personalized medicine. It is expected that pharmacogenetic data will be useful for increasing the treatment efficacy, tolerability, therapeutic adherence, functional recovery, and quality of life in patients with severe psychiatric disorders (SPD). This scoping review investigated the available evidence about the pharmacokinetics, pharmacodynamics, and pharmacogenetics of five new-generation antipsychotics, i.e., cariprazine, brexpiprazole, aripiprazole, lumateperone, and pimavanserin. Based on the analysis of 25 primary and secondary sources and the review of these agents' summaries of product characteristics, aripiprazole benefits from the most relevant data about the impact of gene variability on its pharmacokinetics and pharmacodynamics, with significant consequences on this antipsychotic's efficacy and tolerability. The determination of the CYP2D6 metabolizer status is important when administering aripiprazole, either as monotherapy or associated with other pharmacological agents. Allelic variability in genes encoding dopamine D2, D3, and serotonin, 5HT2A, 5HT2C receptors, COMT, BDNF, and dopamine transporter DAT1 was also associated with different adverse events or variations in the clinical efficacy of aripiprazole. Brexpiprazole also benefits from specific recommendations regarding the CYP2D6 metabolizer status and the risks of associating this antipsychotic with strong/moderate CYP2D6 or CYP3A4 inhibitors. US Food and Drug Administration (FDA) and European Medicines Agency (EMA) recommendations about cariprazine refer to possible pharmacokinetic interactions with strong CYP3A4 inhibitors or inducers. Pharmacogenetic data about cariprazine is sparse, and relevant information regarding gene-drug interactions for lumateperone and pimavanserin is yet lacking. In conclusion, more studies are needed to detect the influence of gene variations on the pharmacokinetics and pharmacodynamics of new-generation antipsychotics. This type of research could increase the ability of clinicians to predict favorable responses to specific antipsychotics and to improve the tolerability of the treatment regimen in patients with SPD.
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Affiliation(s)
- Octavian Vasiliu
- Department of Psychiatry, Dr. Carol Davila Central Military Emergency University Hospital, Bucharest, Romania
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10
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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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11
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Fukuyama K, Motomura E, Okada M. Brexpiprazole Reduces 5-HT7 Receptor Function on Astroglial Transmission Systems. Int J Mol Sci 2022; 23:ijms23126571. [PMID: 35743014 PMCID: PMC9223571 DOI: 10.3390/ijms23126571] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 06/06/2022] [Accepted: 06/10/2022] [Indexed: 12/15/2022] Open
Abstract
Several atypical antipsychotics exert mood-stabilising effects via the modulation of various monoamine receptors and intracellular signallings. Recent pharmacodynamic studies suggested that tripartite synaptic transmission can contribute to the pathophysiology of schizophrenia and mood disorders, their associated cognitive impairment, and several adverse reactions to atypical antipsychotics. Therefore, to explore the mechanisms underlying the antidepressive mood-stabilising and antipsychotic effects of brexpiprazole (Brex), we determined the effects of subchronic administration of therapeutically relevant concentrations/doses of Brex on the protein expression of 5-HT receptors, connexin43, cAMP levels, and intracellular signalling in cultured astrocytes and rat hypothalamus using ultra-high-pressure liquid chromatography with mass spectrometry and capillary immunoblotting systems. Subchronic administration of a therapeutically relevant concentration of Brex (300 nM) downregulated both 5-HT1A (5-HT1AR) and 5-HT7 (5-HT7R) receptors, in addition to phosphorylated Erk (pErk), without affecting phosphorylated Akt in the astroglial plasma membrane. Subchronic administration of 300 nM Brex decreased and increased phosphorylated AMPK and connexin43, respectively, in the astroglial cytosol fraction. A therapeutically relevant concentration of Brex acutely decreased the astroglial cAMP level, whereas, under the inhibition of 5-HT1AR, Brex did not affect astroglial cAMP levels. However, the 5-HT7R-agonist-induced increased astroglial cAMP level was inhibited by Brex. In contrast to the in vitro study, systemic subchronic administration of effective doses of Brex (3 and 10 mg/kg/day for 14 days) increased the cAMP level but did not affect phosphorylated AMPK in the rat hypothalamus. These results suggest several complicated pharmacological features of Brex. Partial 5-HT1AR agonistic action predominates in the low range of therapeutically relevant concentrations of Brex, whereas in the high range, 5-HT7R inverse agonist-like action is overlapped on the 5-HT1A agonistic action. These unique suppressive effects of Brex on 5-HT7R play important roles in the clinical features of Brex regarding its antidepressive mood-stabilising actions.
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12
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Fusaroli M, Raschi E, Giunchi V, Menchetti M, Rimondini Giorgini R, De Ponti F, Poluzzi E. Impulse Control Disorders by Dopamine Partial Agonists: A Pharmacovigilance-Pharmacodynamic Assessment Through the FDA Adverse Event Reporting System. Int J Neuropsychopharmacol 2022; 25:727-736. [PMID: 35639870 PMCID: PMC9515127 DOI: 10.1093/ijnp/pyac031] [Citation(s) in RCA: 4] [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] [Received: 01/03/2022] [Revised: 04/06/2022] [Accepted: 05/24/2022] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND The dopaminergic partial agonism of the so-called third-generation antipsychotics (TGAs; aripiprazole, brexpiprazole, cariprazine) is hypothesized to cause impulse control disorders (ICDs). Relevant warnings by the Food and Drug Administration (FDA) were posted on aripiprazole (2016) and brexpiprazole (2018). Our study investigated the FDA Adverse Event Reporting System and the pharmacodynamic CHEMBL database to further characterize TGA-induced ICDs. METHODS We downloaded and pre-processed the FDA Adverse Event Reporting System up to December 2020. We adapted Bradford Hill criteria to assess each TGA's -and secondarily other antipsychotics'-causal role in inducing ICDs (pathological gambling, compulsive shopping, hyperphagia, hypersexuality), accounting for literature and disproportionality. ICD clinical features were analyzed, and their pathogenesis was investigated using receptor affinities. RESULTS A total of 2708 reports of TGA-related ICDs were found, primarily recording aripiprazole (2545 reports, 94%) among the drugs, and gambling (2018 reports, 75%) among the events. Bradford-Hill criteria displayed evidence for a causal role of each TGA consistent across subpopulations and when correcting for biases. Significant disproportionalities also emerged for lurasidone with compulsive shopping, hyperphagia, and hypersexuality, and olanzapine and ziprasidone with hyperphagia. Time to onset varied between days and years, and positive dechallenge was observed in 20% of cases. Frequently, co-reported events were economic (50%), obsessive-compulsive (44%), and emotional conditions (34%). 5-Hydroxytryptamine receptor type 1a agonism emerged as an additional plausible pathogenetic mechanism. CONCLUSIONS We detected an association between TGAs and ICDs and identified a new signal for lurasidone. ICD characteristics are behavior specific and may heavily impact on life. The role of 5-Hydroxytryptamine receptor type 1a agonism should be further explored.
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Affiliation(s)
- Michele Fusaroli
- Correspondence to: Michele Fusaroli, MD, University of Bologna, Via Irnerio 48, Bologna 40126, Italy ()
| | - Emanuel Raschi
- Pharmacology Unit, Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Valentina Giunchi
- Pharmacology Unit, Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Marco Menchetti
- Pharmacology Unit, Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy,Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | | | - Fabrizio De Ponti
- Pharmacology Unit, Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Elisabetta Poluzzi
- Pharmacology Unit, Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
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13
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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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14
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Li B, Jiang J, Zhou L, Tao X, Sun Q, Liu J, Liu Y, Pang G. Blockade of 5-Hydroxytryptamine 2A Receptor Attenuates Precipitation of Naloxone-Induced Withdrawal Symptoms in Opioid-Exposed Mice. Front Behav Neurosci 2022; 15:797217. [PMID: 35221941 PMCID: PMC8864093 DOI: 10.3389/fnbeh.2021.797217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 12/27/2021] [Indexed: 11/13/2022] Open
Abstract
Heroin dependency has become a global problem and has caused significant clinical and socioeconomic burdens along with devastating medical consequences. Chronic drug exposure alters the expression and functional activity of 5-hydroxytryptamine (serotonin) 2A receptors (5-HT2ARs) in the brain. Furthermore, pharmacological blockade of 5-HT2ARs reduces cue-induced cocaine craving behaviors. In this study, we explored the influence of 5-HT2ARs on heroin-withdrawal behaviors in mice. Black C57BL/6J mice were given gradually increasing (10–50 mg/kg over 4.5 days) doses of heroin to induce heroin dependency, after which naloxone was given to precipitate withdrawal symptoms. MDL100907, a selective and potent 5-HT2AR antagonist, attenuated naloxone-precipitated withdrawal symptoms in these mice. In addition, 5-HT2AR protein levels increased significantly in the medial prefrontal cortex (mPFC), while phosphorylation of extracellular signal-regulated kinase (p-ERK) decreased in the mPFC after heroin exposure. In conclusion, these results suggest that 5-HT2ARs might be involved in the development of opioid dependency and that pharmacological blocking of 5-HT2ARs might be a new therapeutic strategy for heroin dependency.
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Affiliation(s)
- Bing Li
- Center for Medical Research, School of Medicine, Anhui University of Science and Technology, Huainan, China
| | - Junyu Jiang
- Center for Medical Research, School of Medicine, Anhui University of Science and Technology, Huainan, China
| | - Li Zhou
- Center for Medical Research, School of Medicine, Anhui University of Science and Technology, Huainan, China
| | - Xinrong Tao
- Center for Medical Research, School of Medicine, Anhui University of Science and Technology, Huainan, China
| | - Qixian Sun
- Center for Medical Research, School of Medicine, Anhui University of Science and Technology, Huainan, China
| | - Jiaxin Liu
- Center for Medical Research, School of Medicine, Anhui University of Science and Technology, Huainan, China
| | - Yang Liu
- Center for Medical Research, School of Medicine, Anhui University of Science and Technology, Huainan, China
| | - Gang Pang
- College of Basic Medical Sciences, Anhui Medical University, Hefei, China
- *Correspondence: Gang Pang,
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15
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Hart XM, Schmitz CN, Gründer G. Molecular Imaging of Dopamine Partial Agonists in Humans: Implications for Clinical Practice. Front Psychiatry 2022; 13:832209. [PMID: 35463532 PMCID: PMC9020768 DOI: 10.3389/fpsyt.2022.832209] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 03/11/2022] [Indexed: 12/05/2022] Open
Abstract
Positron emission tomography (PET) has been used since the late 1980s for the assessment of relationships between occupancy of D2/3 receptors by antipsychotic drugs in the human brain and the clinical effects and side effects of these compounds in patients. It is now well established for most D2/3 antagonists, both of the first and the second generation, that the ideal occupancy of their target receptors is between approximately 65 and 80%. If the occupancy is below 65%, the probability of treatment response is reduced, if the occupancy is higher than 80%, the risk for extrapyramidal side-effects increases substantially. However, partial agonist antipsychotics behave different from these rules. It has been shown for all three available drugs of this class (aripiprazole, brexpiprazole, cariprazine) that, due to their special pharmacology, a very high target engagement (>90%) not only is not harmful but represents a prerequisite for antipsychotic efficacy. The available PET studies for these drugs are reviewed in this work. It is demonstrated that optimal plasma levels for partial agonist antipsychotics can be derived from these studies, which can guide individual treatment in routine patient care.
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Affiliation(s)
- Xenia M Hart
- Department of Molecular Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Christian N Schmitz
- Department of Molecular Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany.,Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Gerhard Gründer
- Department of Molecular Neuroimaging, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
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16
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Kiss B, Krámos B, Laszlovszky I. Potential Mechanisms for Why Not All Antipsychotics Are Able to Occupy Dopamine D 3 Receptors in the Brain in vivo. Front Psychiatry 2022; 13:785592. [PMID: 35401257 PMCID: PMC8987915 DOI: 10.3389/fpsyt.2022.785592] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 02/25/2022] [Indexed: 11/29/2022] Open
Abstract
Dysfunctions of the dopaminergic system are believed to play a major role in the core symptoms of schizophrenia such as positive, negative, and cognitive symptoms. The first line of treatment of schizophrenia are antipsychotics, a class of medications that targets several neurotransmitter receptors in the brain, including dopaminergic, serotonergic, adrenergic and/or muscarinic receptors, depending on the given agent. Although the currently used antipsychotics display in vitro activity at several receptors, majority of them share the common property of having high/moderate in vitro affinity for dopamine D2 receptors (D2Rs) and D3 receptors (D3Rs). In terms of mode of action, these antipsychotics are either antagonist or partial agonist at the above-mentioned receptors. Although D2Rs and D3Rs possess high degree of homology in their molecular structure, have common signaling pathways and similar in vitro pharmacology, they have different in vivo pharmacology and therefore behavioral roles. The aim of this review, with summarizing preclinical and clinical evidence is to demonstrate that while currently used antipsychotics display substantial in vitro affinity for both D3Rs and D2Rs, only very few can significantly occupy D3Rs in vivo. The relative importance of the level of endogenous extracellular dopamine in the brain and the degree of in vitro D3Rs receptor affinity and selectivity as determinant factors for in vivo D3Rs occupancy by antipsychotics, are also discussed.
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Affiliation(s)
- Béla Kiss
- Pharmacological and Drug Safety Research, Gedeon Richter Plc., Budapest, Hungary
| | - Balázs Krámos
- Spectroscopic Research Department, Gedeon Richter Plc., Budapest, Hungary
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17
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Abstract
PURPOSE OF REVIEW Over the last ten years, the treatment of psychosis has seen a near explosion of creative development in both novel agents and new delivery modalities. The current review summarizes these developments over the past decade (2011-2020). We performed a systematic review utilizing PubMed and PsychInfo with the aim of identifying all the RCT and related analyses in adults with psychosis (schizophrenia and mania). RECENT FINDINGS We identified 11 significant developments: the introduction of new antipsychotics cariprazine, brexpiprazole, lumateperone, and pimavanserin; introduction of new delivery methods: subcutaneous long-acting risperidone, aripiprazole lauroxil, transdermal asenapine, and inhaled loxapine; and the introduction of new approaches such as olanzapine/samidorphan for olanzapine-associated weight gain, examination of the TAAR1 agonist SEP 363,856 as a test of concept, and the combination of Xanomeline/Trospium, an M1 and M4 muscarinic receptor agonist in conjunction with a peripheral anticholinergic. Last decade has seen a tremendous development in second-generation antipsychotics which provides unprecedented treatment options for clinicians in treating psychosis.
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18
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Cookson J, Pimm J. Partial agonists of dopamine receptors: mechanisms and clinical effects of aripiprazole, brexpiprazole and cariprazine. BJPSYCH ADVANCES 2021. [DOI: 10.1192/bja.2021.49] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
SUMMARY
Aripiprazole, brexpiprazole and cariprazine are partial dopamine (and serotonin) agonists developed as novel antipsychotics. This article discusses their pharmacology, evidence on their licensed and off-licence uses (including psychosis, mania, bipolar depression, Tourette syndrome and autism spectrum disorder) and side-effects. In schizophrenia, they have a low risk of Parkinsonism or hyperprolactinaemia, cause modest increases in body weight and are of moderate efficacy.
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19
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Bruno CD, Elmokadem A, Housand C, Jordie EB, Chow CR, Laughren TP, Greenblatt DJ. Impact of Obesity on Brexpiprazole Pharmacokinetics: Proposal for Improved Initiation of Treatment. J Clin Pharmacol 2021; 62:55-65. [PMID: 34339048 DOI: 10.1002/jcph.1947] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 07/23/2021] [Indexed: 01/26/2023]
Abstract
Brexpiprazole is an oral antipsychotic agent indicated for use in patients with schizophrenia or as adjunctive treatment for major depressive disorder. As obesity (body mass index ≥35 kg/m2 ) has the potential to affect drug pharmacokinetics and is a common comorbidity of both schizophrenia and major depressive disorder, it is important to understand changes in brexpiprazole disposition in this population. This study uses a whole-body physiologically based pharmacokinetic model to compare the pharmacokinetics of brexpiprazole in obese and normal-weight (body mass index 18-25 kg/m2 ) individuals known to be cytochrome P450 2D6 extensive metabolizers (EMs) and poor metabolizers (PMs). The physiologically based pharmacokinetic simulations demonstrated significant differences in the time to effective concentrations between obese and normal-weight individuals within metabolizer groups according to the label-recommended titration. Simulations using an alternative dosing strategy of 1 week of twice-daily dosing in obese EMs or 2 weeks of twice-daily dosing in obese poor metabolizers, followed by a return to once-daily dosing, yielded more consistent plasma concentrations between normal-weight and obese patients without exceeding the area under the plasma concentration-time curve observed in the normal-weight EMs. These alternative dosing strategies reduce the time to effective concentrations in obese patients and may improve clinical response to brexpiprazole.
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Affiliation(s)
- Christopher D Bruno
- Emerald Lake Safety, Newport Beach, California, USA.,Tufts University School of Medicine, Boston, Massachusetts, USA
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20
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Cariprazine, A Broad-Spectrum Antipsychotic for the Treatment of Schizophrenia: Pharmacology, Efficacy, and Safety. Adv Ther 2021; 38:3652-3673. [PMID: 34091867 PMCID: PMC8279990 DOI: 10.1007/s12325-021-01797-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 05/15/2021] [Indexed: 12/22/2022]
Abstract
Schizophrenia is characterized by positive, negative, cognitive, and affective symptoms. Antipsychotic medications, which work by blocking the dopamine D2 receptor, are the foundation of pharmacotherapy for schizophrenia to control positive symptoms. Cariprazine is a dopamine D3 receptor-preferring D3/D2 partial agonist antipsychotic that is approved for the treatment of schizophrenia (USA and European Union [EU]) and manic and depressive episodes associated with bipolar I disorder (USA). Partial agonist agents have a lower intrinsic activity at receptors than full agonists, so they act as either functional agonists or functional antagonists depending on the surrounding neurotransmitter environment. Beyond efficacy against positive symptoms, the unique D3-preferring partial agonist pharmacology of cariprazine suggests potential advantages against negative symptoms, and cognitive and functional impairment, which are challenging to treat. The efficacy and safety of cariprazine in adult patients with schizophrenia have been demonstrated in four short-term randomized, double-blind, placebo-controlled clinical trials, two long-term open-label studies, one relapse prevention study, and one prospective negative symptom study versus the active comparator risperidone. Additional post hoc investigations have supported efficacy across individual symptoms and domains in schizophrenia, as well as in diverse areas of interest including cognition, functioning, negative symptoms, hostility, and global well-being. This comprehensive review of cariprazine summarizes its pharmacologic profile, clinical trial evidence, and post hoc investigations. Collective evidence suggests that the pharmacology of cariprazine may offer broad-spectrum efficacy advantages for patients with schizophrenia, including effects against difficult-to-treat negative and cognitive symptoms, as well as functional improvements. Cariprazine was generally safe and well tolerated in patients with short- and long-term exposure and no new safety concerns were associated with longer-duration treatment. Trial registration ClinicalTrials.gov identifiers, NCT00404573, NCT00694707, NCT01104766, NCT01104779, NCT01412060, NCT00839852, NCT01104792.
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21
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Kimura H, Kanahara N, Iyo M. Rationale and neurobiological effects of treatment with antipsychotics in patients with chronic schizophrenia considering dopamine supersensitivity. Behav Brain Res 2021; 403:113126. [PMID: 33460681 DOI: 10.1016/j.bbr.2021.113126] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 12/29/2020] [Accepted: 01/04/2021] [Indexed: 12/12/2022]
Abstract
The long-term treatment of patients with schizophrenia often involves the management of relapses for most patients and the development of treatment resistance in some patients. To stabilize the clinical course and allow as many patients as possible to recover, clinicians need to recognize dopamine supersensitivity, which can be provoked by administration of high dosages of antipsychotics, and deal with it properly. However, no treatment guidelines have addressed this issue. The present review summarized the characteristics of long-acting injectable antipsychotics, dopamine partial agonists, and clozapine in relation to dopamine supersensitivity from the viewpoints of receptor profiles and pharmacokinetics. The potential merits and limitations of these medicines are discussed, as well as the risks of treating patients with established dopamine supersensitivity with these classes of drugs. Finally, the review discussed the biological influence of antipsychotic treatment on the human brain based on findings regarding the relationship between the hippocampus and antipsychotics.
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Affiliation(s)
- Hiroshi Kimura
- Department of Psychiatry, School of Medicine, International University of Health and Welfare, Chiba, Japan; Department of Psychiatry, Chiba University Graduate School of Medicine, Chiba, Japan; Department of Psychiatry, Gakuji-kai Kimura Hospital, Chiba, Japan.
| | - Nobuhisa Kanahara
- Department of Psychiatry, Chiba University Graduate School of Medicine, Chiba, Japan; Division of Medical Treatment and Rehabilitation, Chiba University Center for Forensic Mental Health, Chiba, Japan
| | - Masaomi Iyo
- Department of Psychiatry, Chiba University Graduate School of Medicine, Chiba, Japan
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22
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Neuronal Dopamine D3 Receptors: Translational Implications for Preclinical Research and CNS Disorders. Biomolecules 2021; 11:biom11010104. [PMID: 33466844 PMCID: PMC7830622 DOI: 10.3390/biom11010104] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 01/07/2021] [Accepted: 01/08/2021] [Indexed: 02/06/2023] Open
Abstract
Dopamine (DA), as one of the major neurotransmitters in the central nervous system (CNS) and periphery, exerts its actions through five types of receptors which belong to two major subfamilies such as D1-like (i.e., D1 and D5 receptors) and D2-like (i.e., D2, D3 and D4) receptors. Dopamine D3 receptor (D3R) was cloned 30 years ago, and its distribution in the CNS and in the periphery, molecular structure, cellular signaling mechanisms have been largely explored. Involvement of D3Rs has been recognized in several CNS functions such as movement control, cognition, learning, reward, emotional regulation and social behavior. D3Rs have become a promising target of drug research and great efforts have been made to obtain high affinity ligands (selective agonists, partial agonists and antagonists) in order to elucidate D3R functions. There has been a strong drive behind the efforts to find drug-like compounds with high affinity and selectivity and various functionality for D3Rs in the hope that they would have potential treatment options in CNS diseases such as schizophrenia, drug abuse, Parkinson’s disease, depression, and restless leg syndrome. In this review, we provide an overview and update of the major aspects of research related to D3Rs: distribution in the CNS and periphery, signaling and molecular properties, the status of ligands available for D3R research (agonists, antagonists and partial agonists), behavioral functions of D3Rs, the role in neural networks, and we provide a summary on how the D3R-related drug research has been translated to human therapy.
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Grunze H, Csehi R, Born C, Barabássy Á. Reducing Addiction in Bipolar Disorder via Hacking the Dopaminergic System. Front Psychiatry 2021; 12:803208. [PMID: 34970175 PMCID: PMC8712474 DOI: 10.3389/fpsyt.2021.803208] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 11/23/2021] [Indexed: 02/05/2023] Open
Abstract
The dopaminergic system plays a central and decisive role in substance use disorder (SUD), bipolar disorder (BD), and possibly in a subgroup of patients with refractory depression. Common genetic markers and underlying cellular processes, such as kindling, support the close link between these disorders, which is also expressed by the high rate of comorbidity. Although partial dopamine agonists/antagonists acting on D2 and D3 receptors have an established role in treating BD, their usefulness in SUD is less clear. However, dopamine D3 receptors were shown to play a central role in SUD and BD, making D2/D3 partial agonists/antagonists a potential target for both disorders. This narrative review examines whether these substances bear the promise of a future therapeutic approach especially in patients with comorbid BD and SUD.
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Affiliation(s)
- Heinz Grunze
- Psychiatrie Schwäbisch Hall, Schwäbisch Hall, Germany
- Paracelsus Medical University, Nuremberg, Germany
| | - Réka Csehi
- Gedeon Richter Plc, Medical Division, Budapest, Hungary
- *Correspondence: Réka Csehi
| | - Christoph Born
- Psychiatrie Schwäbisch Hall, Schwäbisch Hall, Germany
- Paracelsus Medical University, Nuremberg, Germany
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Wong DF, Raoufinia A, Bricmont P, Brašić JR, McQuade RD, Forbes RA, Kikuchi T, Kuwabara H. An open-label, positron emission tomography study of the striatal D 2/D 3 receptor occupancy and pharmacokinetics of single-dose oral brexpiprazole in healthy participants. Eur J Clin Pharmacol 2020; 77:717-725. [PMID: 33196868 PMCID: PMC8032567 DOI: 10.1007/s00228-020-03021-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 10/14/2020] [Indexed: 11/07/2022]
Abstract
Purpose The aim of this Phase 1, open-label, positron emission tomography (PET) study was to determine the degree of striatal D2/D3 receptor occupancy induced by the serotonin–dopamine activity modulator, brexpiprazole, at different single dose levels in the range 0.25–6 mg. Methods Occupancy was measured at 4 and 23.5 h post-dose using the D2/D3 receptor antagonist [11C]raclopride. The pharmacokinetics, safety and tolerability of brexpiprazole were assessed in parallel. Results Fifteen healthy participants were enrolled (mean age 33.9 years; 93.3% male). Mean D2/D3 receptor occupancy in the putamen and caudate nucleus increased with brexpiprazole dose, leveled out at 77–88% with brexpiprazole 5 mg and 6 mg at 4 h post-dose, and remained at a similar level at 23.5 h post-dose (74–83%). Estimates of maximum obtainable receptor occupancy (Omax) were 89.2% for the putamen and 95.4% for the caudate nucleus; plasma concentrations predicted to provide 50% of Omax (EC50) were 8.13 ng/mL and 7.75 ng/mL, respectively. Brexpiprazole area under the concentration–time curve (AUC∞) and maximum plasma concentration (Cmax) increased approximately proportional to dose. No notable subjective or objective adverse effects were observed in this cohort. Conclusion By extrapolating the observed single-dose D2/D3 receptor occupancy data in healthy participants, multiple doses of brexpiprazole 2 mg/day and above are expected to result in an efficacious brexpiprazole concentration, consistent with clinically active doses in schizophrenia and major depressive disorder. Trial registration ClinicalTrials.gov NCT00805454 December 9, 2008. Electronic supplementary material The online version of this article (10.1007/s00228-020-03021-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Dean F Wong
- Lab of CNS Neuropsychopharmacology And Multimodal Imaging (CNAMI), Mallinckrodt Institute of Radiology, Washington University in St. Louis, 4525 Scott Avenue Suite 3114, St. Louis, MO, 63110, USA. .,Section of High Resolution Brain PET, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - Arash Raoufinia
- Otsuka Pharmaceutical Development & Commercialization Inc, Princeton, NJ, USA
| | - Patricia Bricmont
- Otsuka Pharmaceutical Development & Commercialization Inc, Princeton, NJ, USA
| | - James R Brašić
- Section of High Resolution Brain PET, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Robert D McQuade
- Otsuka Pharmaceutical Development & Commercialization Inc, Princeton, NJ, USA
| | - Robert A Forbes
- Otsuka Pharmaceutical Development & Commercialization Inc, Princeton, NJ, USA
| | | | - Hiroto Kuwabara
- Section of High Resolution Brain PET, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Cumming P, Abi-Dargham A, Gründer G. Molecular imaging of schizophrenia: Neurochemical findings in a heterogeneous and evolving disorder. Behav Brain Res 2020; 398:113004. [PMID: 33197459 DOI: 10.1016/j.bbr.2020.113004] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 10/22/2020] [Accepted: 10/31/2020] [Indexed: 02/07/2023]
Abstract
The past four decades have seen enormous efforts placed on a search for molecular markers of schizophrenia using positron emission tomography (PET) and single photon emission computed tomography (SPECT). In this narrative review, we cast a broad net to define and summarize what researchers have learned about schizophrenia from molecular imaging studies. Some PET studies of brain energy metabolism with the glucose analogue FDGhave have shown a hypofrontality defect in patients with schizophrenia, but more generally indicate a loss of metabolic coherence between different brain regions. An early finding of significantly increased striatal trapping of the dopamine synthesis tracer FDOPA has survived a meta-analysis of many replications, but the increase is not pathognomonic of the disorder, since one half of patients have entirely normal dopamine synthesis capacity. Similarly, competition SPECT studies show greater basal and amphetamine-evoked dopamine occupancy at post-synaptic dopamine D2/3 receptors in patients with schizophrenia, but the difference is likewise not pathognomonic. We thus propose that molecular imaging studies of brain dopamine indicate neurochemical heterogeneity within the diagnostic entity of schizophrenia. Occupancy studies have established the relevant target engagement by antipsychotic medications at dopamine D2/3 receptors in living brain. There is evidence for elevated frontal cortical dopamine D1 receptors, especially in relation to cognitive deficits in schizophrenia. There is a general lack of consistent findings of abnormalities in serotonin markers, but some evidence for decreased levels of nicotinic receptors in patients. There are sparse and somewhat inconsistent findings of reduced binding of muscarinic, glutamate, and opioid receptors ligands, inconsistent findings of microglial activation, and very recently, evidence of globally reduced levels of synaptic proteins in brain of patients. One study reports a decline in histone acetylase binding that is confined to the dorsolateral prefrontal cortex. In most contexts, the phase of the disease and effects of past or present medication can obscure or confound PET and SPECT findings in schizophrenia.
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Affiliation(s)
- Paul Cumming
- Department of Nuclear Medicine, Inselspital, Bern University, Bern, Switzerland; School of Psychology and Counselling, Queensland University of Technology, Brisbane, Australia.
| | - Anissa Abi-Dargham
- Stony Brook University, Renaissance School of Medicine, Stony Brook, New York, USA
| | - Gerhard Gründer
- Central Institute of Mental Health, Department of Molecular Neuroimaging, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
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Martel JC, Gatti McArthur S. Dopamine Receptor Subtypes, Physiology and Pharmacology: New Ligands and Concepts in Schizophrenia. Front Pharmacol 2020; 11:1003. [PMID: 32765257 PMCID: PMC7379027 DOI: 10.3389/fphar.2020.01003] [Citation(s) in RCA: 119] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 06/22/2020] [Indexed: 12/14/2022] Open
Abstract
Dopamine receptors are widely distributed within the brain where they play critical modulator roles on motor functions, motivation and drive, as well as cognition. The identification of five genes coding for different dopamine receptor subtypes, pharmacologically grouped as D1- (D1 and D5) or D2-like (D2S, D2L, D3, and D4) has allowed the demonstration of differential receptor function in specific neurocircuits. Recent observation on dopamine receptor signaling point at dopamine-glutamate-NMDA neurobiology as the most relevant in schizophrenia and for the development of new therapies. Progress in the chemistry of D1- and D2-like receptor ligands (agonists, antagonists, and partial agonists) has provided more selective compounds possibly able to target the dopamine receptors homo and heterodimers and address different schizophrenia symptoms. Moreover, an extensive evaluation of the functional effect of these agents on dopamine receptor coupling and intracellular signaling highlights important differences that could also result in highly differentiated clinical pharmacology. The review summarizes the recent advances in the field, addressing the relevance of emerging new targets in schizophrenia in particular in relation to the dopamine - glutamate NMDA systems interactions.
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