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Yonezawa K, Uchida H, Yatomi T, Ohtani Y, Nomoto-Takahashi K, Nakajima S, Mimura M, Tani H. Factors Associated with Antidepressant Effects of Ketamine: A Reanalysis of Double-Blind Randomized Placebo-Controlled Trial of Intravenous Ketamine for Treatment-Resistant Depression. PHARMACOPSYCHIATRY 2024; 57:35-40. [PMID: 37846462 DOI: 10.1055/a-2179-8884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2023]
Abstract
INTRODUCTION Predictors of treatment response to intravenous ketamine remain unclear in patients with treatment-resistant depression (TRD); therefore, this study aimed to clarify these predictors using the US National Institutes of Health database of clinical trials. METHODS Data from a placebo-controlled, double-blind, randomized controlled trial were used to assess the efficacy of intravenous ketamine in adult patients with TRD (NCT01920555). For the analysis, data were used from the participants who had received therapeutic doses of intravenous ketamine (i. e., 0.5 and 1.0 mg/kg). Logistic and multivariable regression analyses were conducted to explore the demographic and clinical factors associated with response to treatment or changes in the Hamilton Depression Rating Scale 6 items (HAM-D-6) total score. RESULTS This study included 31 patients with TRD (13 women; mean±standard deviation age, 48.4±10.9 years). Logistic regression analysis showed that the age of onset was positively correlated with treatment response after three days of ketamine administration (β=0.08, p=0.037); however, no association was observed between treatment response and age, sex, baseline HAM-D-6 total score, or dissociative score assessed with the Clinician-Administered Dissociative States Scale 40 min after ketamine infusion. Multiple regression analysis showed that no factors were correlated significantly with the percentage change in the HAM-D-6 total score three days after ketamine administration. DISCUSSION Later disease onset correlates with a better treatment response three days after ketamine infusion in patients with TRD. Glutamatergic signal transmission may be impaired in patients with an earlier onset of depression, resulting in decreased neuroplasticity, which diminishes ketamine response.
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Affiliation(s)
- Kengo Yonezawa
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan
| | - Hiroyuki Uchida
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan
| | - Taisuke Yatomi
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan
| | - Yohei Ohtani
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan
| | | | - Shinichiro Nakajima
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan
| | - Masaru Mimura
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan
| | - Hideaki Tani
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan
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2
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Eiro T, Miyazaki T, Hatano M, Nakajima W, Arisawa T, Takada Y, Kimura K, Sano A, Nakano K, Mihara T, Takayama Y, Ikegaya N, Iwasaki M, Hishimoto A, Noda Y, Miyazaki T, Uchida H, Tani H, Nagai N, Koizumi T, Nakajima S, Mimura M, Matsuda N, Kanai K, Takahashi K, Ito H, Hirano Y, Kimura Y, Matsumoto R, Ikeda A, Takahashi T. Dynamics of AMPA receptors regulate epileptogenesis in patients with epilepsy. Cell Rep Med 2023; 4:101020. [PMID: 37080205 DOI: 10.1016/j.xcrm.2023.101020] [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: 12/07/2022] [Revised: 02/08/2023] [Accepted: 03/22/2023] [Indexed: 04/22/2023]
Abstract
The excitatory glutamate α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPARs) contribute to epileptogenesis. Thirty patients with epilepsy and 31 healthy controls are scanned using positron emission tomography with our recently developed radiotracer for AMPARs, [11C]K-2, which measures the density of cell-surface AMPARs. In patients with focal-onset seizures, an increase in AMPAR trafficking augments the amplitude of abnormal gamma activity detected by electroencephalography. In contrast, patients with generalized-onset seizures exhibit a decrease in AMPARs coupled with increased amplitude of abnormal gamma activity. Patients with epilepsy had reduced AMPAR levels compared with healthy controls, and AMPARs are reduced in larger areas of the cortex in patients with generalized-onset seizures compared with those with focal-onset seizures. Thus, epileptic brain function can be regulated by the enhanced trafficking of AMPAR due to Hebbian plasticity with increased simultaneous neuronal firing and compensational downregulation of cell-surface AMPARs by the synaptic scaling.
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Affiliation(s)
- Tsuyoshi Eiro
- Department of Physiology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan; Department of Psychiatry, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Tomoyuki Miyazaki
- Department of Physiology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Mai Hatano
- Department of Physiology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Waki Nakajima
- Department of Physiology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Tetsu Arisawa
- Department of Physiology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Yuuki Takada
- Department of Physiology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Kimito Kimura
- Department of Physiology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Akane Sano
- Department of Physiology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Kotaro Nakano
- Department of Physiology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Takahiro Mihara
- Department of Health Data Science, Yokohama City University Graduate School of Data Science, Yokohama 236-0004, Japan
| | - Yutaro Takayama
- Department of Neurosurgery, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Naoki Ikegaya
- Department of Neurosurgery, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Masaki Iwasaki
- Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira 187-8551, Japan
| | - Akitoyo Hishimoto
- Department of Psychiatry, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Yoshihiro Noda
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo 160-0016, Japan
| | - Takahiro Miyazaki
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo 160-0016, Japan
| | - Hiroyuki Uchida
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo 160-0016, Japan
| | - Hideaki Tani
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo 160-0016, Japan
| | - Nobuhiro Nagai
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo 160-0016, Japan
| | - Teruki Koizumi
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo 160-0016, Japan
| | - Shinichiro Nakajima
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo 160-0016, Japan
| | - Masaru Mimura
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo 160-0016, Japan
| | - Nozomu Matsuda
- Department of Neurology, Fukushima Medical University, Fukushima 960-1295, Japan
| | - Kazuaki Kanai
- Department of Neurology, Fukushima Medical University, Fukushima 960-1295, Japan
| | - Kazuhiro Takahashi
- Advanced Clinical Research Center, Fukushima Global Medical Science Center, Fukushima Medical University, Fukushima 960-1295, Japan
| | - Hiroshi Ito
- Advanced Clinical Research Center, Fukushima Global Medical Science Center, Fukushima Medical University, Fukushima 960-1295, Japan; Department of Radiology and Nuclear Medicine, Fukushima Medical University, Fukushima 960-1295, Japan
| | - Yoji Hirano
- Department of Neuropsychiatry, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan; Department of Psychiatry, Division of Clinical Neuroscience, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692, Japan
| | - Yuichi Kimura
- Faculty of Informatics, Cyber Informatics Research Institute, Kindai University, Higashi-Osaka 577-8502, Japan
| | - Riki Matsumoto
- Division of Neurology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Akio Ikeda
- Department of Epilepsy, Movement Disorders and Physiology, Kyoto University Graduate School of Medicine, Kyoto 606-8507, Japan
| | - Takuya Takahashi
- Department of Physiology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan; The University of Tokyo, International Research Center for Neurointelligence, Tokyo 113-0033, Japan.
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Chakraborty P, Dey A, Gopalakrishnan AV, Swati K, Ojha S, Prakash A, Kumar D, Ambasta RK, Jha NK, Jha SK, Dewanjee S. Glutamatergic neurotransmission: A potential pharmacotherapeutic target for the treatment of cognitive disorders. Ageing Res Rev 2023; 85:101838. [PMID: 36610558 DOI: 10.1016/j.arr.2022.101838] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Revised: 12/27/2022] [Accepted: 12/29/2022] [Indexed: 01/06/2023]
Abstract
In the mammalian brain, glutamate is regarded to be the primary excitatory neurotransmitter due to its widespread distribution and wide range of metabolic functions. Glutamate plays key roles in regulating neurogenesis, synaptogenesis, neurite outgrowth, and neuron survival in the brain. Ionotropic and metabotropic glutamate receptors, neurotransmitters, neurotensin, neurosteroids, and others co-ordinately formulate a complex glutamatergic network in the brain that maintains optimal excitatory neurotransmission. Cognitive activities are potentially synchronized by the glutamatergic activities in the brain via restoring synaptic plasticity. Dysfunctional glutamate receptors and other glutamatergic components are responsible for the aberrant glutamatergic activity in the brain that cause cognitive impairments, loss of synaptic plasticity, and neuronal damage. Thus, controlling the brain's glutamatergic transmission and modifying glutamate receptor function could be a potential therapeutic strategy for cognitive disorders. Certain drugs that regulate glutamate receptor activities have shown therapeutic promise in improving cognitive functions in preclinical and clinical studies. However, several issues regarding precise functional information of glutamatergic activity are yet to be comprehensively understood. The present article discusses the scope of developing glutamatergic systems as prospective pharmacotherapeutic targets to treat cognitive disorders. Special attention has been given to recent developments, challenges, and future prospects.
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Affiliation(s)
- Pratik Chakraborty
- Advanced Pharmacognosy Research Laboratory, Department of Pharmaceutical Technology, Jadavpur University, Kolkata 700032, India
| | - Abhijit Dey
- Department of Life Sciences, Presidency University, Kolkata 700073, West Bengal, India
| | - Abilash Valsala Gopalakrishnan
- Department of Biomedical Sciences, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu 632014, India
| | - Kumari Swati
- Department of Biotechnology, School of Life Science, Mahatma Gandhi Central University, Motihari, Bihar, India
| | - Shreesh Ojha
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, Abu Dhabi, United Arab Emirates
| | - Anand Prakash
- Department of Biotechnology, School of Life Science, Mahatma Gandhi Central University, Motihari, Bihar, India
| | - Dhruv Kumar
- School of Health Sciences & Technology, UPES University, Dehradun, Uttarakhand 248007, India
| | - Rashmi K Ambasta
- Molecular Neuroscience and Functional Genomics Laboratory, Department of Biotechnology, Delhi Technological University (Formerly DCE), Delhi 110042, India
| | - Niraj Kumar Jha
- Department of Biotechnology, School of Engineering and Technology, Sharda University, Greater Noida 201310, UP, India; School of Bioengineering & Biosciences, Lovely Professional University, Phagwara, Punjab 144411, India.
| | - Saurabh Kumar Jha
- Department of Biotechnology, School of Engineering and Technology, Sharda University, Greater Noida 201310, UP, India; Department of Biotechnology Engineering and Food Technology, Chandigarh University, Mohali 140413, India; Department of Biotechnology, School of Applied & Life Sciences (SALS), Uttaranchal University, Dehradun 248007, India.
| | - Saikat Dewanjee
- Advanced Pharmacognosy Research Laboratory, Department of Pharmaceutical Technology, Jadavpur University, Kolkata 700032, India.
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Wada M, Noda Y, Iwata Y, Tsugawa S, Yoshida K, Tani H, Hirano Y, Koike S, Sasabayashi D, Katayama H, Plitman E, Ohi K, Ueno F, Caravaggio F, Koizumi T, Gerretsen P, Suzuki T, Uchida H, Müller DJ, Mimura M, Remington G, Grace AA, Graff-Guerrero A, Nakajima S. Dopaminergic dysfunction and excitatory/inhibitory imbalance in treatment-resistant schizophrenia and novel neuromodulatory treatment. Mol Psychiatry 2022; 27:2950-2967. [PMID: 35444257 DOI: 10.1038/s41380-022-01572-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 03/31/2022] [Accepted: 04/07/2022] [Indexed: 12/13/2022]
Abstract
Antipsychotic drugs are the mainstay in the treatment of schizophrenia. However, one-third of patients do not show adequate improvement in positive symptoms with non-clozapine antipsychotics. Additionally, approximately half of them show poor response to clozapine, electroconvulsive therapy, or other augmentation strategies. However, the development of novel treatment for these conditions is difficult due to the complex and heterogenous pathophysiology of treatment-resistant schizophrenia (TRS). Therefore, this review provides key findings, potential treatments, and a roadmap for future research in this area. First, we review the neurobiological pathophysiology of TRS, particularly the dopaminergic, glutamatergic, and GABAergic pathways. Next, the limitations of existing and promising treatments are presented. Specifically, this article focuses on the therapeutic potential of neuromodulation, including electroconvulsive therapy, repetitive transcranial magnetic stimulation, transcranial direct current stimulation, and deep brain stimulation. Finally, we propose multivariate analyses that integrate various perspectives of the pathogenesis, such as dopaminergic dysfunction and excitatory/inhibitory imbalance, thereby elucidating the heterogeneity of TRS that could not be obtained by conventional statistics. These analyses can in turn lead to a precision medicine approach with closed-loop neuromodulation targeting the detected pathophysiology of TRS.
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Affiliation(s)
- Masataka Wada
- Department of Neuropsychiatry, Keio University, School of Medicine, Tokyo, Japan
| | - Yoshihiro Noda
- Department of Neuropsychiatry, Keio University, School of Medicine, Tokyo, Japan
| | - Yusuke Iwata
- Department of Neuropsychiatry, University of Yamanashi Faculty of Medicine, Yamanashi, Japan
| | - Sakiko Tsugawa
- Department of Neuropsychiatry, Keio University, School of Medicine, Tokyo, Japan
| | - Kazunari Yoshida
- Department of Neuropsychiatry, Keio University, School of Medicine, Tokyo, Japan.,Tanenbaum Centre for Pharmacogenetics, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada.,Azrieli Adult Neurodevelopmental Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada.,Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Hideaki Tani
- Department of Neuropsychiatry, Keio University, School of Medicine, Tokyo, Japan
| | - Yoji Hirano
- Department of Neuropsychiatry, Kyushu University, Fukuoka, Japan.,Neural Dynamics Laboratory, Research Service, VA Boston Healthcare System, and Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Shinsuke Koike
- Center for Evolutionary Cognitive Sciences, Graduate School of Art and Sciences, The University of Tokyo, Tokyo, Japan
| | - Daiki Sasabayashi
- Department of Neuropsychiatry, University of Toyama Graduate School of Medicine and Pharmaceutical Sciences, Toyama, Japan.,Research Center for Idling Brain Science, University of Toyama, Toyama, Japan
| | - Haruyuki Katayama
- Department of Neuropsychiatry, Keio University, School of Medicine, Tokyo, Japan
| | - Eric Plitman
- Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Kazutaka Ohi
- Department of Psychiatry, Gifu University Graduate School of Medicine, Gifu, Japan
| | - Fumihiko Ueno
- Department of Neuropsychiatry, Keio University, School of Medicine, Tokyo, Japan.,Department of Psychiatry, University of Toronto, Toronto, ON, Canada.,Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, ON, Canada
| | - Fernando Caravaggio
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada.,Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, ON, Canada
| | - Teruki Koizumi
- Department of Neuropsychiatry, Keio University, School of Medicine, Tokyo, Japan.,Department of Psychiatry, National Hospital Organization Shimofusa Psychiatric Medical Center, Chiba, Japan
| | - Philip Gerretsen
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada.,Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, ON, Canada.,Institute of Medical Science, University of Toronto, Toronto, ON, Canada.,Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Takefumi Suzuki
- Department of Neuropsychiatry, University of Yamanashi Faculty of Medicine, Yamanashi, Japan
| | - Hiroyuki Uchida
- Department of Neuropsychiatry, Keio University, School of Medicine, Tokyo, Japan
| | - Daniel J Müller
- Tanenbaum Centre for Pharmacogenetics, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada.,Department of Psychiatry, University of Toronto, Toronto, ON, Canada.,Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Masaru Mimura
- Department of Neuropsychiatry, Keio University, School of Medicine, Tokyo, Japan
| | - Gary Remington
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada.,Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Anthony A Grace
- Departments of Neuroscience, Psychiatry and Psychology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Ariel Graff-Guerrero
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada.,Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, ON, Canada.,Institute of Medical Science, University of Toronto, Toronto, ON, Canada.,Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Shinichiro Nakajima
- Department of Neuropsychiatry, Keio University, School of Medicine, Tokyo, Japan. .,Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, ON, Canada.
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5
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AMPA receptors in schizophrenia: A systematic review of postmortem studies on receptor subunit expression and binding. Schizophr Res 2022; 243:98-109. [PMID: 35247795 DOI: 10.1016/j.schres.2022.02.033] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 12/04/2021] [Accepted: 02/26/2022] [Indexed: 11/22/2022]
Abstract
BACKGROUND While altered expression of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) type receptor has been reported in postmortem studies of schizophrenia, these findings are inconsistent. Therefore, we aimed to systematically review postmortem studies that investigated AMPA receptor expressions in schizophrenia. METHODS A systematic literature search was conducted for postmortem studies that measured AMPA receptor subunit expressions or receptor bindings in schizophrenia compared to healthy individuals on February 3, 2021, using Medline and Embase. RESULTS A total of 39 relevant articles were identified from 1360 initial reports. The dorsolateral prefrontal cortex (DLPFC) was the most investigated region (15 studies), followed by the medial temporal lobe (8 studies). For the DLPFC, 4/15 studies (26.7%) showed increased AMPA receptor binding or subunit expression in patients with schizophrenia compared to that in controls, especially in GRIA1 and GRIA4, 2/15 studies (13.3%) reported a decrease, particularly in GRIA2, and 8/15 studies (56.7%) found no significant differences. A decreased expression or receptor binding was observed in 6/8 studies (75.0%) in the subregions of the hippocampus in patients with schizophrenia compared to that in controls, whereas the other two studies found no significant differences. CONCLUSION Published data have reported decreased subunit expression or receptor binding in the hippocampus in schizophrenia. These findings were inconsistent in other brain regions, which might be due to the heterogeneity of this population, various study design, physiological changes after death, and limited number of studies. Future in vivo studies are warranted to examine AMPA receptor expressions in human brains, together with their comprehensive clinical characterization.
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Miyazaki T, Takayama Y, Iwasaki M, Hatano M, Nakajima W, Ikegaya N, Yamamoto T, Tsuchimoto S, Kato H, Takahashi T. OUP accepted manuscript. Brain Commun 2022; 4:fcac023. [PMID: 35415605 PMCID: PMC8994107 DOI: 10.1093/braincomms/fcac023] [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: 08/30/2021] [Revised: 11/11/2021] [Accepted: 02/03/2022] [Indexed: 11/13/2022] Open
Abstract
Presurgical identification of the epileptogenic zone is a critical determinant of seizure control following surgical resection in epilepsy. Excitatory glutamate α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor is a major component of neurotransmission. Although elevated α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor levels are observed in surgically resected brain areas of patients with epilepsy, it remains unclear whether increased α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor-mediated currents initiate epileptic discharges. We have recently developed the first PET tracer for α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor, [11C]K-2, to visualize and quantify the density of α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors in living human brains. Here, we detected elevated [11C]K-2 uptake in the epileptogenic temporal lobe of patients with mesial temporal lobe epilepsy. Brain areas with high [11C]K-2 uptake are closely colocalized with the location of equivalent current dipoles estimated by magnetoencephalography or with seizure onset zones detected by intracranial electroencephalogram. These results suggest that epileptic discharges initiate from brain areas with increased α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors, providing a biological basis for epileptic discharges and an additional non-invasive option to identify the epileptogenic zone in patients with mesial temporal lobe epilepsy.
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Affiliation(s)
- Tomoyuki Miyazaki
- Department of Physiology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Yutaro Takayama
- Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira 187-8551, Japan
| | - Masaki Iwasaki
- Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira 187-8551, Japan
| | - Mai Hatano
- Department of Physiology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Waki Nakajima
- Department of Physiology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Naoki Ikegaya
- Department of Neurosurgery, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Tetsuya Yamamoto
- Department of Neurosurgery, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Shohei Tsuchimoto
- Division of System Neuroscience, National Institute for Physiological Sciences, Okazaki 444-8585, Japan
| | - Hiroki Kato
- Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Suita 565-0871, Japan
| | - Takuya Takahashi
- Department of Physiology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
- Correspondence to: Takuya Takahashi Department of Physiology, Yokohama City University Graduate School of Medicine Fukuura 3-9, Kanazawa-ku, Yokohama, 236-0004, Japan E-mail:
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