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Kruk-Slomka M, Adamski B, Slomka T, Biala G. Inhibitors of Endocannabinoids' Enzymatic Degradation as a Potential Target of the Memory Disturbances in an Acute N-Methyl-D-Aspartate (NMDA) Receptor Hypofunction Model of Schizophrenia in Mice. Int J Mol Sci 2023; 24:11400. [PMID: 37511157 PMCID: PMC10380236 DOI: 10.3390/ijms241411400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 07/08/2023] [Accepted: 07/11/2023] [Indexed: 07/30/2023] Open
Abstract
Treating schizophrenia with the available pharmacotherapy is difficult. One possible strategy is focused on the modulation of the function of the endocannabinoid system (ECS). The ECS is comprised of cannabinoid (CB) receptors, endocannabinoids and enzymes responsible for the metabolism of endocannabinoids (fatty acid hydrolase (FAAH) and monoacylglycerol lipase (MAGL)). Here, the aim of the experiments was to evaluate the impact of inhibitors of endocannabinoids' enzymatic degradation in the brain: KML-29 (MAGL inhibitor), JZL-195 (MAGL/FAAH inhibitor) and PF-3845 (FAAH inhibitor), on the memory disturbances typical for schizophrenia in an acute N-methyl-D-aspartate (NMDA) receptor hypofunction animal model of schizophrenia (i.e., injection of MK-801, an NMDA receptor antagonist). The memory-like responses were assessed in the passive avoidance (PA) test. A single administration of KML-29 or PF-3845 had a positive effect on the memory processes, but an acute administration of JZL-195 impaired cognition in mice in the PA test. Additionally, the combined administration of a PA-ineffective dose of KML-29 (5 mg/kg) or PF-3845 (3 mg/kg) attenuated the MK-801-induced cognitive impairment (0.6 mg/kg). Our results suggest that the indirect regulation of endocannabinoids' concentration in the brain through the use of selected inhibitors may positively affect memory disorders, and thus increase the effectiveness of modern pharmacotherapy of schizophrenia.
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Affiliation(s)
- Marta Kruk-Slomka
- Department of Pharmacology and Pharmacodynamics, Medical University of Lublin, 4a Chodzki Street, 20-093 Lublin, Poland
| | - Bartlomiej Adamski
- Department of Pharmacology and Pharmacodynamics, Medical University of Lublin, 4a Chodzki Street, 20-093 Lublin, Poland
| | - Tomasz Slomka
- Department of Medical Informatics and Statistics with E-Health Lab, Medical University of Lublin, Jaczewskiego 4 Street, 20-954 Lublin, Poland
| | - Grazyna Biala
- Department of Pharmacology and Pharmacodynamics, Medical University of Lublin, 4a Chodzki Street, 20-093 Lublin, Poland
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Maksymetz J, Byun NE, Luessen DJ, Li B, Barry RL, Gore JC, Niswender CM, Lindsley CW, Joffe ME, Conn PJ. mGlu 1 potentiation enhances prelimbic somatostatin interneuron activity to rescue schizophrenia-like physiological and cognitive deficits. Cell Rep 2021; 37:109950. [PMID: 34731619 PMCID: PMC8628371 DOI: 10.1016/j.celrep.2021.109950] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 08/09/2021] [Accepted: 10/14/2021] [Indexed: 01/03/2023] Open
Abstract
Evidence for prefrontal cortical (PFC) GABAergic dysfunction is one of the most consistent findings in schizophrenia and may contribute to cognitive deficits. Recent studies suggest that the mGlu1 subtype of metabotropic glutamate receptor regulates cortical inhibition; however, understanding the mechanisms through which mGlu1 positive allosteric modulators (PAMs) regulate PFC microcircuit function and cognition is essential for advancing these potential therapeutics toward the clinic. We report a series of electrophysiology, optogenetic, pharmacological magnetic resonance imaging, and animal behavior studies demonstrating that activation of mGlu1 receptors increases inhibitory transmission in the prelimbic PFC by selective excitation of somatostatin-expressing interneurons (SST-INs). An mGlu1 PAM reverses cortical hyperactivity and concomitant cognitive deficits induced by N-methyl-d-aspartate (NMDA) receptor antagonists. Using in vivo optogenetics, we show that prelimbic SST-INs are necessary for mGlu1 PAM efficacy. Collectively, these findings suggest that mGlu1 PAMs could reverse cortical GABAergic deficits and exhibit efficacy in treating cognitive dysfunction in schizophrenia.
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Affiliation(s)
- James Maksymetz
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA; Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA
| | - Nellie E Byun
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA; Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Deborah J Luessen
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA; Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA
| | - Brianna Li
- Vanderbilt University, Nashville, TN 37232, USA
| | - Robert L Barry
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Radiology & Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - John C Gore
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Radiology & Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Biomedical Engineering, Vanderbilt University, Nashville, TN 37232, USA
| | - Colleen M Niswender
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA; Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Institute for Chemical Biology, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37232, USA
| | - Craig W Lindsley
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA; Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Institute for Chemical Biology, Vanderbilt University, Nashville, TN 37232, USA; Department of Chemistry, Vanderbilt University, Nashville, TN 37232, USA
| | - Max E Joffe
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA; Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA
| | - P Jeffrey Conn
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA; Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Institute for Chemical Biology, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37232, USA.
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Snyder MA, Gao WJ. NMDA receptor hypofunction for schizophrenia revisited: Perspectives from epigenetic mechanisms. Schizophr Res 2020; 217:60-70. [PMID: 30979669 PMCID: PMC7258307 DOI: 10.1016/j.schres.2019.03.010] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 03/08/2019] [Accepted: 03/11/2019] [Indexed: 02/06/2023]
Abstract
Schizophrenia (SZ) is a neurodevelopmental disorder with cognitive deficits manifesting during early stages of the disease. Evidence suggests that genetic factors in combination with environmental insults lead to complex changes to glutamatergic, GABAergic, and dopaminergic systems. In particular, the N-methyl-d-aspartate receptor (NMDAR), a major glutamate receptor subtype, is implicated in both the disease progression and symptoms of SZ. NMDARs are critical for synaptic plasticity and cortical maturation, as well as learning and memory processes. In fact, any deviation from normal NMDAR expression and function can have devastating consequences. Surprisingly, there is little evidence from human patients that direct mutations of NMDAR genes contribute to SZ. One intriguing hypothesis is that epigenetic changes, which could result from early insults, alter protein expression and contribute to the NMDAR hypofunction found in SZ. Epigenetics is referred to as modifications that alter gene transcription without changing the DNA sequence itself. In this review, we first discuss how epigenetic changes to NMDAR genes could contribute to NMDAR hypofunction. We then explore how NMDAR hypofunction may contribute to epigenetic changes in other proteins or genes that lead to synaptic dysfunction and symptoms in SZ. We argue that NMDAR hypofunction occurs in early stage of the disease, and it may consequentially initiate GABA and dopamine deficits. Therefore, targeting NMDAR dysfunction during the early stages would be a promising avenue for prevention and therapeutic intervention of cognitive and social deficits that remain untreatable. Finally, we discuss potential questions regarding the epigenetic of SZ and future directions for research.
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Affiliation(s)
- Melissa A. Snyder
- Ottawa Hospital Research Institute, Ottawa, Ontario, Canada, K1H 8M5,Correspondence: Wen-Jun Gao, M.D., Ph.D., Department of Neurobiology and Anatomy, Drexel University College of Medicine, 2900 Queen Lane, Philadelphia, PA 19129, Phone: (215) 991-8907, Fax: (215) 843-9802, ; Melissa A. Snyder, Ph.D.,
| | - Wen-Jun Gao
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, PA 19129, United States of America.
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Matousova M, Soucek R, Tloustova E, Slavikova B, Chodounska H, Mertlikova-Kaiserova H, Kudova E. Pregn-5-en-3β-ol and androst-5-en-3β-ol dicarboxylic acid esters as potential therapeutics for NMDA hypofunction: In vitro safety assessment and plasma stability. Steroids 2019; 147:4-9. [PMID: 30296546 DOI: 10.1016/j.steroids.2018.09.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2018] [Revised: 09/18/2018] [Accepted: 09/24/2018] [Indexed: 10/28/2022]
Abstract
Neurosteroids are endogenous steroidal compounds that can modulate neuronal receptors. N-Methyl-D-aspartate receptors (NMDARs) are glutamate-gated, calcium-permeable ion channels that are of particular interest, as they participate in synaptic transmission and are implicated in various processes, such as learning, memory, or long-term neuronal potentiation. Positive allosteric modulators that increase the activity of NMDARs may provide a therapeutic aid for patients suffering from neuropsychiatric disorders where NMDAR hypofunction is thought to be involved, such as intellectual disability, autism spectrum disorder, or schizophrenia. We recently described a new class of pregn-5-ene and androst-5-ene 3β-dicarboxylic acid hemiesters (2-24) as potent positive modulators of NMDARs. Considering the recommended guidelines for the early stage development of new, potent compounds, we conducted an in vitro safety assessment and plasma stability screening to evaluate their druglikeness. First, compounds were screened for their hepatotoxicity and mitochondrial toxicity in a HepG2 cell line. Second, toxicity in primary rat postnatal neurons was estimated. Next, the ability of compounds 2-24 to cross a Caco-2 monolayer was also studied. Finally, rat and human plasma stability screening revealed an unforeseen high stability of the C-3 hemiester moiety. In summary, by using potency/efficacy towards NMDARs data along with toxicity profile, Caco-2 permeability and plasma stability, compounds 14 and 15 were selected for further in vivo animal studies.
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Affiliation(s)
- Marika Matousova
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nam. 2, Prague 6, Dejvice 16610, Czech Republic
| | - Radko Soucek
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nam. 2, Prague 6, Dejvice 16610, Czech Republic
| | - Eva Tloustova
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nam. 2, Prague 6, Dejvice 16610, Czech Republic
| | - Barbora Slavikova
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nam. 2, Prague 6, Dejvice 16610, Czech Republic
| | - Hana Chodounska
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nam. 2, Prague 6, Dejvice 16610, Czech Republic
| | - Helena Mertlikova-Kaiserova
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nam. 2, Prague 6, Dejvice 16610, Czech Republic
| | - Eva Kudova
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nam. 2, Prague 6, Dejvice 16610, Czech Republic.
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Steinmann S, Leicht G, Mulert C. The interhemispheric miscommunication theory of auditory verbal hallucinations in schizophrenia. Int J Psychophysiol 2019; 145:83-90. [PMID: 30738815 DOI: 10.1016/j.ijpsycho.2019.02.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 01/29/2019] [Accepted: 02/06/2019] [Indexed: 01/16/2023]
Abstract
Auditory verbal hallucinations (AVH) are hallmark symptoms of schizophrenia and have been linked to abnormal activation, connectivity and integration within the auditory, language, and memory brain networks. The interhemispheric miscommunication theory of AVH is based on a steadily growing number of studies using a variety of modalities (EEG, fMRI, DTI) reporting that both altered integrity of the interhemispheric auditory pathways and disturbed functional gamma-band synchrony between right and left auditory cortices significantly contribute to abnormal auditory processing and the emergence of AVH. Moreover, initial studies using pharmacological EEG and 1H MR spectroscopy provided first insights into the underlying neurochemistry of AVH. It has been suggested that the observed interhemispheric gamma-band alterations might be mediated by an excitatory-to-inhibitory (E/I) imbalance due to dysfunction of N-methyl-d-aspartate receptor (NMDAR). In support, a potential NMDAR hypofunction is proposed to be compensated by increased levels of glutamate in prefrontal and auditory brain areas. In this mini-review paper, we used the levels of explanation approach and present how interhemispheric brain connectivity (brain-imaging level) corresponds to auditory perception (cognitive level), and eventually how these parameters are related to changes in neurotransmission (cellular level) and to the occurrence of AVH (clinical level). To the best of our knowledge, this is the first overview that overcomes traditional boundaries and presents converging evidence from different levels of knowledge that validate and support each other, and particularly point toward the role of an interhemispheric miscommunication in AVH.
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Affiliation(s)
- Saskia Steinmann
- Psychiatry Neuroimaging Branch, Department of Psychiatry and Psychotherapy, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; Psychiatry Neuroimaging Laboratory, Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
| | - Gregor Leicht
- Psychiatry Neuroimaging Branch, Department of Psychiatry and Psychotherapy, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christoph Mulert
- Centre for Psychiatry and Psychotherapy, Justus-Liebig-University, Giessen, Germany
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McGregor C, Riordan A, Thornton J. Estrogens and the cognitive symptoms of schizophrenia: Possible neuroprotective mechanisms. Front Neuroendocrinol 2017; 47:19-33. [PMID: 28673758 DOI: 10.1016/j.yfrne.2017.06.003] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 06/25/2017] [Accepted: 06/27/2017] [Indexed: 02/07/2023]
Abstract
Schizophrenia is a complex neuropsychiatric illness with marked sex differences. Women have later onset and lesser symptoms, which has led to the hypothesis that estrogens are protective in schizophrenia. Cognitive dysfunction is a hallmark of the disease and the symptom most correlated with functional outcome. Here we describe a number of mechanisms by which estrogens may be therapeutic in schizophrenia, with a focus on cognitive symptoms. We review the relationship between estrogens and brain derived neurotrophic factor, neuroinflammation, NMDA receptors, GABA receptors, and luteinizing hormone. Exploring these pathways may enable novel treatments for schizophrenia and a greater understanding of this devastating disease.
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Affiliation(s)
- Claire McGregor
- Department of Neuroscience, Oberlin College, 119 Woodland St, Oberlin, OH 44074, USA.
| | - Alexander Riordan
- Department of Neuroscience, Oberlin College, 119 Woodland St, Oberlin, OH 44074, USA
| | - Janice Thornton
- Department of Neuroscience, Oberlin College, 119 Woodland St, Oberlin, OH 44074, USA
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Banks PJ, Burroughs AC, Barker GRI, Brown JT, Warburton EC, Bashir ZI. Disruption of hippocampal-prefrontal cortex activity by dopamine D2R-dependent LTD of NMDAR transmission. Proc Natl Acad Sci U S A 2015; 112:11096-101. [PMID: 26286993 PMCID: PMC4568284 DOI: 10.1073/pnas.1512064112] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Functional connectivity between the hippocampus and prefrontal cortex (PFC) is essential for associative recognition memory and working memory. Disruption of hippocampal-PFC synchrony occurs in schizophrenia, which is characterized by hypofunction of NMDA receptor (NMDAR)-mediated transmission. We demonstrate that activity of dopamine D2-like receptors (D2Rs) leads selectively to long-term depression (LTD) of hippocampal-PFC NMDAR-mediated synaptic transmission. We show that dopamine-dependent LTD of NMDAR-mediated transmission profoundly disrupts normal synaptic transmission between hippocampus and PFC. These results show how dopaminergic activation induces long-term hypofunction of NMDARs, which can contribute to disordered functional connectivity, a characteristic that is a hallmark of psychiatric disorders such as schizophrenia.
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Affiliation(s)
- Paul James Banks
- School of Physiology and Pharmacology, University of Bristol, Bristol, BS8 1TD, United Kingdom
| | | | | | - Jon Thomas Brown
- Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, Exeter, EX4 4PS, United Kingdom
| | | | - Zafar Iqbal Bashir
- School of Physiology and Pharmacology, University of Bristol, Bristol, BS8 1TD, United Kingdom;
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Li ML, Hu XQ, Li F, Gao WJ. Perspectives on the mGluR2/3 agonists as a therapeutic target for schizophrenia: Still promising or a dead end? Prog Neuropsychopharmacol Biol Psychiatry 2015; 60:66-76. [PMID: 25724760 PMCID: PMC4426221 DOI: 10.1016/j.pnpbp.2015.02.012] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Revised: 02/16/2015] [Accepted: 02/17/2015] [Indexed: 01/08/2023]
Abstract
Group II metabotropic glutamate receptor (mGluR2/3) agonists once showed promise as non-dopaminergic antipsychotic drugs because of their efficacy in alleviating symptoms of schizophrenia (SZ) in both animal models and human patients. However, the recent failure of Phase III clinical trials dealt a huge blow to the scientific community and the aftershock of the setback in mGluR2/3 research can be felt everywhere from grant support and laboratory studies to paper publication. An immediate question raised is whether mGluR2/3 is still a promising therapeutic target for schizophrenia. Answering this question is not easy, but apparently a new strategy is needed. This article provides a focused review of literature on the study of mGluR2/3 agonists, especially on mGluR2/3 agonists' mechanism of action and efficacy in both normal conditions and animal models of SZ, as well as clinical studies in human patients with the disease. We argue that the cellular and molecular actions of mGluR2/3 agonists, the distinct roles between mGluR2 and mGluR3, as well as their effects on different stages of the disease and different subpopulations of patients, remain incompletely studied. Until the mechanisms associated with mGluR2/3 are clearly elucidated and all treatment options are tested, it would be a great mistake to terminate the study of mGluR2/3 as a therapeutic target for schizophrenia. This review will thus shed light on the comprehensive features of the translational potential mGluR2/3 agonists as well as the need for further research into the more selective activation of mGluR2.
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Affiliation(s)
- Meng-Lin Li
- Drexel University College of Medicine, Philadelphia, PA, USA,Department of Rehabilitation, Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Xi-Quan Hu
- Department of Rehabilitation, Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Feng Li
- Department of Neurobiology and Anatomy, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
| | - Wen-Jun Gao
- Drexel University College of Medicine, Philadelphia, PA, USA.
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Grüter T, Wiescholleck V, Dubovyk V, Aliane V, Manahan-Vaughan D. Altered neuronal excitability underlies impaired hippocampal function in an animal model of psychosis. Front Behav Neurosci 2015; 9:117. [PMID: 26042007 PMCID: PMC4438226 DOI: 10.3389/fnbeh.2015.00117] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 04/22/2015] [Indexed: 01/12/2023] Open
Abstract
Psychosis is accompanied by severe attentional deficits, and impairments in associational-memory processing and sensory information processing that are ascribed to dysfunctions in prefrontal and hippocampal function. Disruptions of glutamatergic signaling may underlie these alterations: Antagonism of the N-methyl-D-aspartate receptor (NMDAR) results in similar molecular, cellular, cognitive and behavioral changes in rodents and/or humans as those that occur in psychosis, raising the question as to whether changes in glutamatergic transmission may be intrinsic to the pathophysiology of the disease. In an animal model of psychosis that comprises treatment with the irreversible NMDAR-antagonist, MK801, we explored the cellular mechanisms that may underlie hippocampal dysfunction in psychosis. MK801-treatment resulted in a profound loss of hippocampal LTP that was evident 4 weeks after treatment. Whereas neuronal expression of the immediate early gene, Arc, was enhanced in the hippocampus by spatial learning in controls, MK801-treated animals failed to show activity-dependent increases in Arc expression. By contrast, a significant increase in basal Arc expression in the absence of learning was evident compared to controls. Paired-pulse (PP) facilitation was increased at the 40 ms interval indicating that NMDAR and/or fast GABAergic-mediated neurotransmission was disrupted. In line with this, MK801-treatment resulted in a significant decrease in GABA(A), and increase in GABA(B)-receptor-expression in PFC, along with a significant increase of GABA(B)- and NMDAR-GluN2B expression in the dentate gyrus. NMDAR-GluN1 or GluN2A subunit expression was unchanged. These data suggest that in psychosis, deficits in hippocampus-dependent memory may be caused by a loss of hippocampal LTP that arises through enhanced hippocampal neuronal excitability, altered GluN2B and GABA receptor expression and an uncoupling of the hippocampus-prefrontal cortex circuitry.
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Affiliation(s)
- Thomas Grüter
- Medical Faculty, Department of Neurophysiology, Ruhr University Bochum Bochum, Germany ; International Graduate School of Neuroscience, Ruhr University Bochum Bochum, Germany
| | | | - Valentyna Dubovyk
- Medical Faculty, Department of Neurophysiology, Ruhr University Bochum Bochum, Germany
| | - Verena Aliane
- Medical Faculty, Department of Neurophysiology, Ruhr University Bochum Bochum, Germany
| | - Denise Manahan-Vaughan
- Medical Faculty, Department of Neurophysiology, Ruhr University Bochum Bochum, Germany ; International Graduate School of Neuroscience, Ruhr University Bochum Bochum, Germany
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Gomes FV, Issy AC, Ferreira FR, Viveros MP, Del Bel EA, Guimarães FS. Cannabidiol attenuates sensorimotor gating disruption and molecular changes induced by chronic antagonism of NMDA receptors in mice. Int J Neuropsychopharmacol 2015; 18:pyu041. [PMID: 25618402 PMCID: PMC4376539 DOI: 10.1093/ijnp/pyu041] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Preclinical and clinical data suggest that cannabidiol (CBD), a major non-psychotomimetic compound from Cannabis sativa, induces antipsychotic-like effects. However, the antipsychotic properties of repeated CBD treatment have been poorly investigated. Behavioral changes induced by repeated treatment with glutamate N-methyl-D-aspartate receptor (NMDAR) antagonists have been proposed as an animal model of schizophrenia-like signs. In the present study, we evaluated if repeated treatment with CBD would attenuate the behavioral and molecular modifications induced by chronic administration of one of these antagonists, MK-801. METHODS Male C57BL/6J mice received daily i.p. injections of MK-801 (0.1, 0.5, or 1mg/kg) for 14, 21, or 28 days. Twenty-four hours after the last injection, animals were submitted to the prepulse inhibition (PPI) test. After that, we investigated if repeated treatment with CBD (15, 30, and 60mg/kg) would attenuate the PPI impairment induced by chronic treatment with MK-801 (1mg/kg; 28 days). CBD treatment began on the 6th day after the start of MK-801 administration and continued until the end of the treatment. Immediately after the PPI, the mice brains were removed and processed to evaluate the molecular changes. We measured changes in FosB/ΔFosB and parvalbumin (PV) expression, a marker of neuronal activity and a calcium-binding protein expressed in a subclass of GABAergic interneurons, respectively. Changes in mRNA expression of the NMDAR GluN1 subunit gene (GRN1) were also evaluated. CBD effects were compared to those induced by the atypical antipsychotic clozapine. RESULTS MK-801 administration at the dose of 1mg/kg for 28 days impaired PPI responses. Chronic treatment with CBD (30 and 60mg/kg) attenuated PPI impairment. MK-801 treatment increased FosB/ΔFosB expression and decreased PV expression in the medial prefrontal cortex. A decreased mRNA level of GRN1 in the hippocampus was also observed. All the molecular changes were attenuated by CBD. CBD by itself did not induce any effect. Moreover, CBD effects were similar to those induced by repeated clozapine treatment. CONCLUSIONS These results indicate that repeated treatment with CBD, similar to clozapine, reverses the psychotomimetic-like effects and attenuates molecular changes observed after chronic administration of an NMDAR antagonist. These data support the view that CBD may have antipsychotic properties.
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Affiliation(s)
- Felipe V Gomes
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo, Brazil (Gomes and Guimarães); Department of Physiology, Faculty of Odontology of Ribeirão Preto, University of São Paulo, Brazil (Issy and Del Bel); Center for Interdisciplinary Research on Applied Neurosciences, University of São Paulo, Brazil (Gomes, Issy, Del Bel, and Guimarães); Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil (Ferreira); Department of Physiology (Animal Physiology II), Faculty of Biology, Complutense University of Madrid, Spain (Viveros).
| | - Ana Carolina Issy
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo, Brazil (Gomes and Guimarães); Department of Physiology, Faculty of Odontology of Ribeirão Preto, University of São Paulo, Brazil (Issy and Del Bel); Center for Interdisciplinary Research on Applied Neurosciences, University of São Paulo, Brazil (Gomes, Issy, Del Bel, and Guimarães); Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil (Ferreira); Department of Physiology (Animal Physiology II), Faculty of Biology, Complutense University of Madrid, Spain (Viveros)
| | - Frederico R Ferreira
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo, Brazil (Gomes and Guimarães); Department of Physiology, Faculty of Odontology of Ribeirão Preto, University of São Paulo, Brazil (Issy and Del Bel); Center for Interdisciplinary Research on Applied Neurosciences, University of São Paulo, Brazil (Gomes, Issy, Del Bel, and Guimarães); Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil (Ferreira); Department of Physiology (Animal Physiology II), Faculty of Biology, Complutense University of Madrid, Spain (Viveros)
| | - Maria-Paz Viveros
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo, Brazil (Gomes and Guimarães); Department of Physiology, Faculty of Odontology of Ribeirão Preto, University of São Paulo, Brazil (Issy and Del Bel); Center for Interdisciplinary Research on Applied Neurosciences, University of São Paulo, Brazil (Gomes, Issy, Del Bel, and Guimarães); Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil (Ferreira); Department of Physiology (Animal Physiology II), Faculty of Biology, Complutense University of Madrid, Spain (Viveros)
| | - Elaine A Del Bel
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo, Brazil (Gomes and Guimarães); Department of Physiology, Faculty of Odontology of Ribeirão Preto, University of São Paulo, Brazil (Issy and Del Bel); Center for Interdisciplinary Research on Applied Neurosciences, University of São Paulo, Brazil (Gomes, Issy, Del Bel, and Guimarães); Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil (Ferreira); Department of Physiology (Animal Physiology II), Faculty of Biology, Complutense University of Madrid, Spain (Viveros)
| | - Francisco S Guimarães
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo, Brazil (Gomes and Guimarães); Department of Physiology, Faculty of Odontology of Ribeirão Preto, University of São Paulo, Brazil (Issy and Del Bel); Center for Interdisciplinary Research on Applied Neurosciences, University of São Paulo, Brazil (Gomes, Issy, Del Bel, and Guimarães); Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil (Ferreira); Department of Physiology (Animal Physiology II), Faculty of Biology, Complutense University of Madrid, Spain (Viveros)
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Blot K, Bai J, Otani S. The effect of non-competitive NMDA receptor antagonist MK-801 on neuronal activity in rodent prefrontal cortex: an animal model for cognitive symptoms of schizophrenia. ACTA ACUST UNITED AC 2013; 107:448-51. [PMID: 23603055 DOI: 10.1016/j.jphysparis.2013.04.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 04/09/2013] [Accepted: 04/11/2013] [Indexed: 11/29/2022]
Abstract
Schizophrenia affects about 1% of the world population and is a major socio-economical problem in ours societies. Cognitive symptoms are particularly resistant to current treatments and are believed to be closely related to an altered function of prefrontal cortex (PFC). Particularly, abnormalities in the plasticity processes in the PFC are a candidate mechanism underlying cognitive symptoms, and the recent evidences in patients are in line with this hypothesis. Animal pharmacological models of cognitive symptoms, notably with non-competitive NMDA receptor antagonists such as MK-801, are commonly used to investigate the underlying cellular and molecular mechanisms of schizophrenia. However, it is still unknown whether in these animal models, impairments in plasticity of PFC neurons are present. In this article, we briefly summarize the current knowledge on the effect of non-competitive NMDA receptor antagonist MK-801 on medial PFC (mPFC) neuronal activity and then introduce a form of plasticity found after acute exposure to MK-801, which was accompanied by cognitive deficits. These observations suggest a potential correlation between cognitive deficits and the aberrant plasticity in the mPFC in the animal model of schizophrenia.
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Affiliation(s)
- Kevin Blot
- INSERM U952/CNRS UMR 7224, Université Pierre et Marie Curie, 9 quai Saint Bernard, 75252 Paris cedex 05, France.
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Abstract
An increasing level of N-methyl-D-aspartate (NMDA) receptor hypofunction within the brain is associated with memory and learning impairments, with psychosis, and ultimately with excitotoxic brain injury. As the brain ages, the NMDA receptor system becomes progressively hypofunctional, contributing to decreases in memory and learning performance. In those individuals destined to develop Alzheimer's disease, other abnormalities (eg, amyloidopathy and oxidative stress) interact to increase the NMDA receptor hypofunction (NRHypo) burden. In these vulnerable individuals, the brain then enters into a severe and persistent NRHypo state, which can lead to widespread neurodegeneration with accompanying mental symptoms and further cognitive deterioration. If the hypotheses described herein prove correct, treatment implications may be considerable. Pharmacological methods for preventing the overstimulation of vulnerable corticolimbic pyramidal neurons developed in an animal model may be applicable to the prevention and treatment of Alzheimer's disease.
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Affiliation(s)
- J W Newcomer
- Departement of Psychiatry, Washington University School of Medicine, St Louis, Mo, USA
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13
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Newcomer JW. NMDA receptor function, memory, and brain aging. Dialogues Clin Neurosci 2000; 2:219-32. [PMID: 22034391 PMCID: PMC3181613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 03/23/2024]
Abstract
An increasing level of N-methyl-D-aspartate (NMDA) receptor hypofunction within the brain is associated with memory and learning impairments, with psychosis, and ultimately with excitotoxic brain injury. As the brain ages, the NMDA receptor system becomes progressively hypofunctional, contributing to decreases in memory and learning performance. In those individuals destined to develop Alzheimer's disease, other abnormalities (eg, amyloidopathy and oxidative stress) interact to increase the NMDA receptor hypofunction (NRHypo) burden. In these vulnerable individuals, the brain then enters into a severe and persistent NRHypo state, which can lead to widespread neurodegeneration with accompanying mental symptoms and further cognitive deterioration. If the hypotheses described herein prove correct, treatment implications may be considerable. Pharmacological methods for preventing the overstimulation of vulnerable corticolimbic pyramidal neurons developed in an animal model may be applicable to the prevention and treatment of Alzheimer's disease.
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