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Parellada E, Gassó P. Glutamate and microglia activation as a driver of dendritic apoptosis: a core pathophysiological mechanism to understand schizophrenia. Transl Psychiatry 2021; 11:271. [PMID: 33958577 PMCID: PMC8102516 DOI: 10.1038/s41398-021-01385-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 04/09/2021] [Accepted: 04/20/2021] [Indexed: 02/03/2023] Open
Abstract
Schizophrenia disorder remains an unsolved puzzle. However, the integration of recent findings from genetics, molecular biology, neuroimaging, animal models and translational clinical research offers evidence that the synaptic overpruning hypothesis of schizophrenia needs to be reassessed. During a critical period of neurodevelopment and owing to an imbalance of excitatory glutamatergic pyramidal neurons and inhibitory GABAergic interneurons, a regionally-located glutamate storm might occur, triggering excessive dendritic pruning with the activation of local dendritic apoptosis machinery. The apoptotic loss of dendritic spines would be aggravated by microglia activation through a recently described signaling system from complement abnormalities and proteins of the MHC, thus implicating the immune system in schizophrenia. Overpruning of dendritic spines coupled with aberrant synaptic plasticity, an essential function for learning and memory, would lead to brain misconnections and synaptic inefficiency underlying the primary negative symptoms and cognitive deficits of schizophrenia. This driving hypothesis has relevant therapeutic implications, including the importance of pharmacological interventions during the prodromal phase or the transition to psychosis, targeting apoptosis, microglia cells or the glutamate storm. Future research on apoptosis and brain integrity should combine brain imaging, CSF biomarkers, animal models and cell biology.
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Affiliation(s)
- Eduard Parellada
- Barcelona Clínic Schizophrenia Unit (BCSU). Institute of Neuroscience, Hospital Clínic of Barcelona, University of Barcelona, Barcelona, Catalonia, Spain.
- The August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Catalonia, Spain.
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain.
| | - Patricia Gassó
- Barcelona Clínic Schizophrenia Unit (BCSU). Institute of Neuroscience, Hospital Clínic of Barcelona, University of Barcelona, Barcelona, Catalonia, Spain
- The August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Catalonia, Spain
- Department of Basic Clinical Practice, Unit of Pharmacology, University of Barcelona, Barcelona, Catalonia, Spain
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Burstein ES. Relevance of 5-HT 2A Receptor Modulation of Pyramidal Cell Excitability for Dementia-Related Psychosis: Implications for Pharmacotherapy. CNS Drugs 2021; 35:727-741. [PMID: 34224112 PMCID: PMC8310514 DOI: 10.1007/s40263-021-00836-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/09/2021] [Indexed: 01/05/2023]
Abstract
Psychosis occurs across a wide variety of dementias with differing etiologies, including Alzheimer's dementia, Parkinson's dementia, Lewy body dementia, frontotemporal dementia, and vascular dementia. Pimavanserin, a selective serotonin 5-HT2A receptor (5-HT2AR) inverse agonist, has shown promising results in clinical trials by reducing the frequency and/or severity of hallucinations and delusions and the risk of relapse of these symptoms in patients with dementia-related psychosis. A literature review was conducted to identify mechanisms that explain the role of 5-HT2ARs in both the etiology and treatment of dementia-related psychosis. This review revealed that most pathological changes commonly associated with neurodegenerative diseases cause one or more of the following events to occur: reduced synaptic contact of gamma aminobutyric acid (GABA)-ergic interneurons with glutamatergic pyramidal cells, reduced cortical innervation from subcortical structures, and altered 5-HT2AR expression levels. Each of these events promotes increased pyramidal cell hyperexcitability and disruption of excitatory/inhibitory balance, facilitating emergence of psychotic behaviors. The brain regions affected by these pathological changes largely coincide with areas expressing high levels of 5-HT2ARs. At the cellular level, 5-HT2ARs are most highly expressed on cortical glutamatergic pyramidal cells, where they regulate pyramidal cell excitability. The common effects of different neurodegenerative diseases on pyramidal cell excitability together with the close anatomical and functional connection of 5-HT2ARs to pyramidal cell excitability may explain why suppressing 5-HT2AR activity could be an effective strategy to treat dementia-related psychosis.
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Affiliation(s)
- Ethan S. Burstein
- Acadia Pharmaceuticals Inc, 12830 El Camino Real, Suite 400, San Diego, CA 92130 USA
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Nahar L, Delacroix BM, Nam HW. The Role of Parvalbumin Interneurons in Neurotransmitter Balance and Neurological Disease. Front Psychiatry 2021; 12:679960. [PMID: 34220586 PMCID: PMC8249927 DOI: 10.3389/fpsyt.2021.679960] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 05/24/2021] [Indexed: 12/21/2022] Open
Abstract
While great progress has been made in the understanding of neurological illnesses, the pathologies, and etiologies that give rise to these diseases still remain an enigma, thus, also making treatments for them more challenging. For effective and individualized treatment, it is beneficial to identify the underlying mechanisms that govern the associated cognitive and behavioral processes that go awry in neurological disorders. Parvalbumin fast-spiking interneurons (Pv-FSI) are GABAergic cells that are only a small fraction of the brain's neuronal network, but manifest unique cellular and molecular properties that drastically influence the downstream effects on signaling and ultimately change cognitive behaviors. Proper brain functioning relies heavily on neuronal communication which Pv-FSI regulates, excitatory-inhibitory balances and GABAergic disinhibition between circuitries. This review highlights the depth of Pv-FSI involvement in the cortex, hippocampus, and striatum, as it pertains to expression, neurotransmission, role in neurological disorders, and dysfunction, as well as cognitive behavior and reward-seeking. Recent research has indicated that Pv-FSI play pivotal roles in the molecular pathophysiology and cognitive-behavioral deficits that are core features of many psychiatric disorders, such as schizophrenia, autism spectrum disorders, Alzheimer's disease, and drug addiction. This suggests that Pv-FSI could be viable targets for treatment of these disorders and thus calls for further examination of the undeniable impact Pv-FSI have on the brain and cognitive behavior.
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Affiliation(s)
- Lailun Nahar
- Department of Pharmacology, Toxicology, and Neuroscience, Louisiana State University Health Sciences Center, Shreveport, LA, United States
| | - Blake M Delacroix
- Department of Pharmacology, Toxicology, and Neuroscience, Louisiana State University Health Sciences Center, Shreveport, LA, United States
| | - Hyung W Nam
- Department of Pharmacology, Toxicology, and Neuroscience, Louisiana State University Health Sciences Center, Shreveport, LA, United States
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CRISPR/Cas9-engineered Gad1 elimination in rats leads to complex behavioral changes: implications for schizophrenia. Transl Psychiatry 2020; 10:426. [PMID: 33293518 PMCID: PMC7723991 DOI: 10.1038/s41398-020-01108-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 11/06/2020] [Accepted: 11/16/2020] [Indexed: 12/19/2022] Open
Abstract
GABAergic dysfunctions have been implicated in the pathogenesis of schizophrenia, especially the associated cognitive impairments. The GABA synthetic enzyme glutamate decarboxylase 67-kDa isoform (GAD67) encoded by the GAD1 gene is downregulated in the brains of patients with schizophrenia. Furthermore, a patient with schizophrenia harboring a homozygous mutation of GAD1 has recently been discovered. However, it remains unclear whether loss of function of GAD1 leads to the symptoms observed in schizophrenia, including cognitive impairment. One of the obstacles faced in experimental studies to address this issue is the perinatal lethality of Gad1 knockout (KO) mice, which precluded characterization at the adult stage. In the present study, we successfully generated Gad1 KO rats using CRISPR/Cas9 genome editing technology. Surprisingly, 33% of Gad1 KO rats survived to adulthood and could be subjected to further characterization. The GABA concentration in the Gad1 KO cerebrum was reduced to ~52% of the level in wild-type rats. Gad1 KO rats exhibited impairments in both spatial reference and working memory without affecting adult neurogenesis in the hippocampus. In addition, Gad1 KO rats showed a wide range of behavioral alterations, such as enhanced sensitivity to an NMDA receptor antagonist, hypoactivity in a novel environment, and decreased preference for social novelty. Taken together, the results suggest that Gad1 KO rats could provide a novel model covering not only cognitive deficits but also other aspects of the disorder. Furthermore, the present study teaches an important lesson: differences between species should be considered when developing animal models of human diseases.
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Phensy A, Lindquist KL, Lindquist KA, Bairuty D, Gauba E, Guo L, Tian J, Du H, Kroener S. Deletion of the Mitochondrial Matrix Protein CyclophilinD Prevents Parvalbumin Interneuron Dysfunctionand Cognitive Deficits in a Mouse Model of NMDA Hypofunction. J Neurosci 2020; 40:6121-6132. [PMID: 32605939 PMCID: PMC7406283 DOI: 10.1523/jneurosci.0880-20.2020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 05/28/2020] [Accepted: 06/22/2020] [Indexed: 12/23/2022] Open
Abstract
Redox dysregulation and oxidative stress are final common pathways in the pathophysiology of a variety of psychiatric disorders, including schizophrenia. Oxidative stress causes dysfunction of GABAergic parvalbumin (PV)-positive interneurons (PVI), which are crucial for the coordination of neuronal synchrony during sensory and cognitive processing. Mitochondria are the main source of reactive oxygen species (ROS) in neurons and they control synaptic activity through their roles in energy production and intracellular calcium homeostasis. We have previously shown that in male mice transient blockade of NMDA receptors (NMDARs) during development [subcutaneous injections of 30 mg/kg ketamine (KET) on postnatal days 7, 9, and 11] results in long-lasting alterations in synaptic transmission and reduced PV expression in the adult prefrontal cortex (PFC), contributing to a behavioral phenotype that mimics multiple symptoms associated with schizophrenia. These changes correlate with oxidative stress and impaired mitochondrial function in both PVI and pyramidal cells. Here, we show that genetic deletion (Ppif-/-) of the mitochondrial matrix protein cyclophilin D (CypD) prevents perinatal KET-induced increases in ROS and the resulting deficits in PVI function, and changes in excitatory and inhibitory synaptic transmission in the PFC. Deletion of CypD also prevented KET-induced behavioral deficits in cognitive flexibility, social interaction, and novel object recognition (NOR). Taken together, these data highlight how mitochondrial activity may play an integral role in modulating PVI-mediated cognitive processes.SIGNIFICANCE STATEMENT Mitochondria are important modulators of oxidative stress and cell function, yet how mitochondrial dysfunction affects cell activity and synaptic transmission in psychiatric illnesses is not well understood. NMDA receptor (NMDAR) blockade with ketamine (KET) during development causes oxidative stress, dysfunction of parvalbumin (PV)-positive interneurons (PVI), and long-lasting physiological and behavioral changes. Here we show that mice deficient for the mitochondrial matrix protein cyclophilin D (CypD) show robust protection from PVI dysfunction following perinatal NMDAR blockade. Mitochondria serve as an essential node for a number of stress-induced signaling pathways and our experiments suggest that failure of mitochondrial redox regulation can contribute to PVI dysfunction.
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Affiliation(s)
- Aarron Phensy
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, Texas 75080
| | - Kathy L Lindquist
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, Texas 75080
| | - Karen A Lindquist
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, Texas 75080
| | - Dania Bairuty
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, Texas 75080
| | - Esha Gauba
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, Texas 75080
| | - Lan Guo
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, Texas 75080
| | - Jing Tian
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, Texas 75080
| | - Heng Du
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, Texas 75080
| | - Sven Kroener
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, Texas 75080
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Martínez-Pinteño A, García-Cerro S, Mas S, Torres T, Boloc D, Rodríguez N, Lafuente A, Gassó P, Arnaiz JA, Parellada E. The positive allosteric modulator of the mGlu2 receptor JNJ-46356479 partially improves neuropathological deficits and schizophrenia-like behaviors in a postnatal ketamine mice model. J Psychiatr Res 2020; 126:8-18. [PMID: 32407891 DOI: 10.1016/j.jpsychires.2020.04.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 04/10/2020] [Accepted: 04/18/2020] [Indexed: 12/30/2022]
Abstract
Current antipsychotics have limited efficacy in controlling cognitive and negative symptoms of schizophrenia (SZ). Glutamatergic dysregulation has been implicated in the pathophysiology of SZ, based on the capacity of N-methyl-D-aspartate receptor (NMDAR) antagonists such as ketamine (KET) to induce SZ-like behaviors. This could be related to their putative neuropathological effect on gamma-aminobutyric (GABAergic) interneurons expressing parvalbumin (PV), which would lead to a hyperglutamatergic condition. Metabotropic glutamate receptor 2 (mGluR2) negatively modulates glutamate release and has been considered a potential clinical target for novel antipsychotics drugs. Our aim was to evaluate the efficacy of JNJ-46356479 (JNJ), a positive allosteric modulator (PAM) of the mGluR2, in reversing neuropathological and behavioral deficits induced in a postnatal KET mice model of SZ. These animals presented impaired spontaneous alternation in the Y-maze test, suggesting deficits in spatial working memory, and a decrease in social motivation and memory, assessed in both the Three-Chamber and the Five Trial Social Memory tests. Interestingly, JNJ treatment of adult mice partially reversed these deficits. Mice treated with KET also showed a reduction in PV+ in the mPFC and dentate gyrus together with an increase in c-Fos expression in this hippocampal area. Compared to the control group, mice treated with KET + JNJ showed a similar PV density and c-Fos activity pattern. Our results suggest that pharmacological treatment with a PAM of the mGluR2 such as JNJ could help improve cognitive and negative symptoms related to SZ.
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Affiliation(s)
| | - Susana García-Cerro
- Department of Basic Clinical Practice, Unit of Pharmacology, University of Barcelona, Spain
| | - Sergi Mas
- Department of Basic Clinical Practice, Unit of Pharmacology, University of Barcelona, Spain; The August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain
| | - Teresa Torres
- Department of Basic Clinical Practice, Unit of Pharmacology, University of Barcelona, Spain
| | - Daniel Boloc
- Department of Medicine, University of Barcelona, Spain
| | - Natalia Rodríguez
- Department of Basic Clinical Practice, Unit of Pharmacology, University of Barcelona, Spain
| | - Amalia Lafuente
- Department of Basic Clinical Practice, Unit of Pharmacology, University of Barcelona, Spain; The August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain
| | - Patricia Gassó
- Department of Basic Clinical Practice, Unit of Pharmacology, University of Barcelona, Spain; The August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
| | - Joan Albert Arnaiz
- Department of Basic Clinical Practice, Unit of Pharmacology, University of Barcelona, Spain; The August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain; Clinical Pharmacology Department, Hospital Clínic de Barcelona, Spain.
| | - Eduard Parellada
- The August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain; Department of Medicine, University of Barcelona, Spain; Barcelona Clinic Schizophrenia Unit (BCSU), Institute of Neuroscience, Hospital Clinic of Barcelona, University of Barcelona, Spain.
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Schiavone S, Morgese MG, Bove M, Colia AL, Maffione AB, Tucci P, Trabace L, Cuomo V. Ketamine administration induces early and persistent neurochemical imbalance and altered NADPH oxidase in mice. Prog Neuropsychopharmacol Biol Psychiatry 2020; 96:109750. [PMID: 31446158 DOI: 10.1016/j.pnpbp.2019.109750] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 08/19/2019] [Accepted: 08/20/2019] [Indexed: 12/15/2022]
Abstract
Administration in adulthood of subanaesthetic doses of ketamine, an NMDA receptor (NMDA-R) antagonist, is commonly used to induce psychotic-like alterations in rodents. The NADPH oxidase (NOX) derived-oxidative stress has been shown to be implicated in ketamine-induced neurochemical dysfunctions and in the loss of parvalbumin (PV)-positive interneurons associated to the administration of this NMDA receptor antagonist in adult mice. However, very few data are available on the effects of early ketamine administration and its contribution to the development of long-term dysfunctions leading to psychosis. Here, by administering a subanaesthetic dose of ketamine (30 mg/kg i.p.) to mice at postnatal days (PNDs) 7, 9 and 11, we aimed at investigating early neurochemical and oxidative stress-related alterations induced by this NMDA-R antagonist in specific brain regions of mice pups, i.e. prefrontal cortex (PFC) and nucleus accumbens (NAcc) and to assess whether these alterations lasted until the adult period. To this purpose, we evaluated glutamatergic, glutamine and GABAergic tissue levels, as well as PV amount in the PFC, both two hours after the last ketamine injection (PND 11) and at 10 weeks of age. Dopamine (DA) tissue levels and DA turnover were also evaluated in the NAcc at the same time points. Levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a reliable biomarker of oxidative stress, as well as of the free radical producers NOX1 and NOX2 enzymes, were also assessed in both PFC and NAcc of ketamine-treated pups and adult mice. Ketamine-treated pups showed increased cortical levels of glutamate (GLU) and glutamine, as well as similar GABA amount compared to controls, together with an early reduction of cortical PV levels. In the adult period, the same was observed for GLU and PV, whereas GABA levels were increased and no changes in glutamine amount were detected. Ketamine administration in early life induced a decrease in DA tissue levels and an increase of DA turnover which were also detectable at 10 weeks of age. These alterations were accompanied by 8-OHdG elevations in both PFC and NAcc at the two considered life stages. The expression of NOX1 was significantly reduced in these brain regions following ketamine administration at early life stages, while, in the adult period, significant elevation of this enzyme was observed. Levels of NOX2 were found increased at both time points. Our results suggest that an early increase of NOX2-derived oxidative stress may contribute to the development of neurochemical imbalance in PFC and NAcc, induced by ketamine administration. Modifications of NOX1 expression might represent, instead, an early response of the developing brain to a neurotoxic insult, followed by a later attempt to counterbalance ketamine-related detrimental effects.
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Affiliation(s)
- Stefania Schiavone
- Department of Clinical and Experimental Medicine, University of Foggia, Viale Pinto, 1, 71122 Foggia, Italy.
| | - Maria Grazia Morgese
- Department of Clinical and Experimental Medicine, University of Foggia, Viale Pinto, 1, 71122 Foggia, Italy.
| | - Maria Bove
- Department of Clinical and Experimental Medicine, University of Foggia, Viale Pinto, 1, 71122 Foggia, Italy.
| | - Anna Laura Colia
- Department of Clinical and Experimental Medicine, University of Foggia, Viale Pinto, 1, 71122 Foggia, Italy.
| | - Angela Bruna Maffione
- Department of Clinical and Experimental Medicine, University of Foggia, Viale Pinto, 1, 71122 Foggia, Italy.
| | - Paolo Tucci
- Department of Clinical and Experimental Medicine, University of Foggia, Viale Pinto, 1, 71122 Foggia, Italy.
| | - Luigia Trabace
- Department of Clinical and Experimental Medicine, University of Foggia, Viale Pinto, 1, 71122 Foggia, Italy.
| | - Vincenzo Cuomo
- Department of Physiology and Pharmacology "Vittorio Erspamer", Sapienza University of Rome, Piazzale Aldo Moro, 5, 00185 Rome, Italy.
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Wang C, Inselman A, Liu S, Liu F. Potential mechanisms for phencyclidine/ketamine-induced brain structural alterations and behavioral consequences. Neurotoxicology 2019; 76:213-219. [PMID: 31812709 DOI: 10.1016/j.neuro.2019.12.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 11/24/2019] [Accepted: 12/04/2019] [Indexed: 01/30/2023]
Abstract
Evidence of structural abnormalities in the nervous system of recreational drug [e.g., phencyclidine (PCP) or ketamine] users and/or preclinical animal research models suggests interference with the activity of multiple neurotransmitters, particularly glutamate neurotransmission. The damage to the central nervous system (CNS) may include neuronal loss, synaptic changes, disturbed neural network formation and reduced projections to subcortical fields. Notably, the reduced projections may considerably compromise the establishment of the subcortical areas, such as the nucleus accumbens located in the basal forebrain. With its abundant dopaminergic innervation, the nucleus accumbens is believed to be directly associated with addictive behaviors and mental disorders. This review seeks to delineate the relationship between PCP/ketamine-induced loss of cortical neurons and the reduced level of polysialic acid neural cell adhesion molecule (PSA-NCAM) in the striatum, and the likely changes in striatal synaptogenesis during development. The basic mechanism of how PSA-NCAM cell surface expression may be regulated will also be discussed, as well as the hypothesis that PSA-NCAM activity is critical to the regulation of synaptic protein expression. Overall, the present review will address the general hypothesis that damage/interruption of cortico-striatal communication and subcortical synaptogenesis could underlie the erratic/sensitization or addictive states produced by chronic or prolonged PCP/ketamine usage.
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Affiliation(s)
- Cheng Wang
- Division of Neurotoxicology, National Center for Toxicological Research/U.S. Food & Drug Administration, Jefferson, AR, United States.
| | - Amy Inselman
- Division of Systems Biology, National Center for Toxicological Research/U.S. Food & Drug Administration, Jefferson, AR, United States
| | - Shuliang Liu
- Division of Neurotoxicology, National Center for Toxicological Research/U.S. Food & Drug Administration, Jefferson, AR, United States
| | - Fang Liu
- Division of Neurotoxicology, National Center for Toxicological Research/U.S. Food & Drug Administration, Jefferson, AR, United States.
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Intracellular mechanisms and behavioral changes in mouse model of attention deficit hyperactivity disorder: Importance of age-specific NMDA receptor blockade. Pharmacol Biochem Behav 2019; 188:172830. [PMID: 31756355 DOI: 10.1016/j.pbb.2019.172830] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Revised: 11/18/2019] [Accepted: 11/18/2019] [Indexed: 11/21/2022]
Abstract
Exposure of NMDA receptor antagonists during developmental stages leads to behavioral consequences like attention deficit hyperactivity disorder (ADHD). However, the underlying molecular mechanisms have remained poorly understood. Herein, we studied the phosphorylated Akt (pAkt) and caspase-3, the key regulators of neuronal cell survival/death, as the probable downstream targets of MK-801 often used to engender ADHD-like condition. Swiss albino mice at postnatal days (PND) 7, 14 or 21 were injected with a single dose of MK-801 and evaluated for hyperactivity (open field test) and memory deficit at adolescence (PND 30) and adult stages (PND 60). PND 7 or 14 treatment groups (but not PND 21) consistently showed hyperactivity at the adolescence stage. A significant increase in working and reference memory errors in radial arm maze was noted at the adolescence age. PND 7 group continued to display the symptoms even in adulthood. All the treatment groups showed a significant decrease in the percent alterations (Y-maze) and discrimination index (novel object recognition test) at adolescence age. A significant increase in caspase-3 expression was noted in the prefrontal cortex (PFC) and hippocampus, whereas increased pAkt was noticed only in the hippocampus, following a single injection of MK-801 at PND 7. Concurrently, PND 7 treatment group showed significantly decreased neuronal nuclei (NeuN) expression (a marker for mature neurons) in the dentate gyrus, cornu ammonis-3 and PFC, but not in cornu ammonis-1, at adolescence age. We suggest that the observed symptoms of ADHD at adolescence and adulthood stages may be linked to alteration in pAkt and caspase-3 followed MK-801 treatment at PND 7.
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Yao L, Wang Z, Deng D, Yan R, Ju J, Zhou Q. The impact of D-cycloserine and sarcosine on in vivo frontal neural activity in a schizophrenia-like model. BMC Psychiatry 2019; 19:314. [PMID: 31653237 PMCID: PMC6814999 DOI: 10.1186/s12888-019-2306-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 09/30/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND N-methyl-D-aspartate receptor (NMDAR) hypofunction has been proposed to underlie the pathogenesis of schizophrenia. Specifically, reduced function of NMDARs leads to altered balance between excitation and inhibition which further drives neural network malfunctions. Clinical studies suggested that NMDAR modulators (glycine, D-serine, D-cycloserine and glycine transporter inhibitors) may be beneficial in treating schizophrenia patients. Preclinical evidence also suggested that these NMDAR modulators may enhance synaptic NMDAR function and synaptic plasticity in brain slices. However, an important issue that has not been addressed is whether these NMDAR modulators modulate neural activity/spiking in vivo. METHODS By using in vivo calcium imaging and single unit recording, we tested the effect of D-cycloserine, sarcosine (glycine transporter 1 inhibitor) and glycine, on schizophrenia-like model mice. RESULTS In vivo neural activity is significantly higher in the schizophrenia-like model mice, compared to control mice. D-cycloserine and sarcosine showed no significant effect on neural activity in the schizophrenia-like model mice. Glycine induced a large reduction in movement in home cage and reduced in vivo brain activity in control mice which prevented further analysis of its effect in schizophrenia-like model mice. CONCLUSIONS We conclude that there is no significant impact of the tested NMDAR modulators on neural spiking in the schizophrenia-like model mice.
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Affiliation(s)
- Lulu Yao
- 0000 0001 2256 9319grid.11135.37School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055 China
| | - Zongliang Wang
- 0000 0001 2256 9319grid.11135.37School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055 China
| | - Di Deng
- 0000 0001 2256 9319grid.11135.37School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055 China
| | - Rongzhen Yan
- 0000 0001 2256 9319grid.11135.37School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055 China
| | - Jun Ju
- 0000 0001 2256 9319grid.11135.37School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055 China
| | - Qiang Zhou
- School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055, China. .,State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen, 518055, China.
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Lum JS, du Bois TM, Mattner F, Katsifis A, Brown SJ, Huang XF, Newell KA. Increased translocator protein (TSPO) binding throughout neurodevelopment in the perinatal phencyclidine rodent model of schizophrenia. Schizophr Res 2019; 212:243-245. [PMID: 31420201 DOI: 10.1016/j.schres.2019.07.041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 07/24/2019] [Accepted: 07/27/2019] [Indexed: 11/29/2022]
Affiliation(s)
- Jeremy S Lum
- Illawarra Health and Medical Research Institute, Wollongong, Australia; Molecular Horizons and School of Medicine, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales 2522, Australia.
| | - Teresa M du Bois
- Illawarra Health and Medical Research Institute, Wollongong, Australia; Molecular Horizons and School of Medicine, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - Filomena Mattner
- Department of Molecular Imaging, Royal Prince Alfred Hospital, Missenden Road, Camperdown, 2050, Australia
| | - Andrew Katsifis
- Department of Molecular Imaging, Royal Prince Alfred Hospital, Missenden Road, Camperdown, 2050, Australia
| | - Samara J Brown
- Illawarra Health and Medical Research Institute, Wollongong, Australia; Molecular Horizons and School of Medicine, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - Xu-Feng Huang
- Illawarra Health and Medical Research Institute, Wollongong, Australia; Molecular Horizons and School of Medicine, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - Kelly A Newell
- Illawarra Health and Medical Research Institute, Wollongong, Australia; Molecular Horizons and School of Medicine, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales 2522, Australia
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12
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Lee G, Zhou Y. NMDAR Hypofunction Animal Models of Schizophrenia. Front Mol Neurosci 2019; 12:185. [PMID: 31417356 PMCID: PMC6685005 DOI: 10.3389/fnmol.2019.00185] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 07/17/2019] [Indexed: 12/20/2022] Open
Abstract
The N-methyl-d-aspartate receptor (NMDAR) hypofunction hypothesis has been proposed to help understand the etiology and pathophysiology of schizophrenia. This hypothesis was based on early observations that NMDAR antagonists could induce a full range of symptoms of schizophrenia in normal human subjects. Accumulating evidence in humans and animal studies points to NMDAR hypofunctionality as a convergence point for various symptoms of schizophrenia. Here we review animal models of NMDAR hypofunction generated by pharmacological and genetic approaches, and how they relate to the pathophysiology of schizophrenia. In addition, we discuss the limitations of animal models of NMDAR hypofunction and their potential utility for therapeutic applications.
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Affiliation(s)
| | - Yi Zhou
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, FL, United States
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13
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Downregulation of Npas4 in parvalbumin interneurons and cognitive deficits after neonatal NMDA receptor blockade: relevance for schizophrenia. Transl Psychiatry 2019; 9:99. [PMID: 30792384 PMCID: PMC6385315 DOI: 10.1038/s41398-019-0436-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 01/29/2019] [Accepted: 02/12/2019] [Indexed: 12/17/2022] Open
Abstract
Dysfunction of prefrontal parvalbumin (PV+) interneurons has been linked with severe cognitive deficits as observed in several neurodevelopmental disorders including schizophrenia. However, whether a specific aspect of PV+ neurons deregulation, or a specific molecular mechanism within PV+ neurons is responsible for cognitive deficits and other behavioral impairments remain to be determined. Here, we induced cognitive deficits and altered the prefrontal PV system in mice by exposing them neonatally to the NMDA receptor antagonist ketamine. We observed that the cognitive deficits and hyperactivity induced by neonatal ketamine were associated with a downregulation of Npas4 expression specifically in PV+ neurons. To determine whether Npas4 downregulation-induced dysfunction of PV+ neurons could be a molecular contributor to the cognitive and behavioral impairments reported after neonatal ketamine, we used a transgenic Cre-Lox approach. Reduced Npas4 expression within PV+ neurons replicates deficits in short-term memory observed after neonatal ketamine, but does not reproduce disturbances in general activity. Our data show for the first time that the brain-specific transcription factor Npas4 may be an important contributor to PV+ neurons dysfunction in neurodevelopmental disorders, and thereby could contribute to the cognitive deficits observed in diseases characterized by abnormal functioning of PV+ neurons such as schizophrenia. These findings provide a potential novel therapeutic target to rescue the cognitive impairments of schizophrenia that remain to date unresponsive to treatments.
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14
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Ueno H, Suemitsu S, Murakami S, Kitamura N, Wani K, Matsumoto Y, Okamoto M, Ishihara T. Region-specific reduction of parvalbumin neurons and behavioral changes in adult mice following single exposure to cranial irradiation. Int J Radiat Biol 2019; 95:611-625. [PMID: 30601685 DOI: 10.1080/09553002.2019.1564081] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
PURPOSE Ionizing irradiation has several long-term effects including progressive cognitive impairment. Cognitive deterioration generally appears to be caused by abnormalities in the hippocampal dentate gyrus, with abnormal function of parvalbumin-expressing interneurons (PV neurons) in the cerebral cortex. PV neurons are vulnerable to oxidative stress, which can be caused by ionizing irradiation. We speculated that selective impairment of specific brain regions due to ionizing irradiation may alter the degree of cognitive impairment. METHODS We irradiated mature mouse brains with 20 Gy-ionizing irradiation. Subsequently, we analyzed behavioral abnormalities and changes in the number of PV neurons. RESULTS PV neuron density was significantly lower in some cortical regions of irradiated mice than in control mice. Within 1 week of irradiation, both body weight and temperature of irradiated mice decreased. In the forced swim test, irradiated mice spent significantly less time immobile than did control mice. However, irradiated mice did not display any abnormalities in the elevated plus maze test, Y-maze test, tail suspension test, and social interaction test between 3 to 6 days after irradiation. CONCLUSIONS These results suggest that high-dose irradiation is less likely to cause brain dysfunction in the subacute phase. Moreover, the vulnerability of PV neurons appears to be brain-region specific.
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Affiliation(s)
- Hiroshi Ueno
- a Department of Medical Technology , Kawasaki University of Medical Welfare , Okayama , Japan.,b Department of Medical Technology, Graduate School of Health Sciences , Okayama University , Okayama , Japan
| | - Shunsuke Suemitsu
- c Department of Psychiatry , Kawasaki Medical School , Kurashiki , Japan
| | - Shinji Murakami
- c Department of Psychiatry , Kawasaki Medical School , Kurashiki , Japan
| | - Naoya Kitamura
- c Department of Psychiatry , Kawasaki Medical School , Kurashiki , Japan
| | - Kenta Wani
- c Department of Psychiatry , Kawasaki Medical School , Kurashiki , Japan
| | - Yosuke Matsumoto
- d Department of Neuropsychiatry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences , Okayama University , Okayama , Japan
| | - Motoi Okamoto
- b Department of Medical Technology, Graduate School of Health Sciences , Okayama University , Okayama , Japan
| | - Takeshi Ishihara
- c Department of Psychiatry , Kawasaki Medical School , Kurashiki , Japan
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15
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Rajagopal L, Huang M, Michael E, Kwon S, Meltzer HY. TPA-023 attenuates subchronic phencyclidine-induced declarative and reversal learning deficits via GABA A receptor agonist mechanism: possible therapeutic target for cognitive deficit in schizophrenia. Neuropsychopharmacology 2018; 43:2468-2477. [PMID: 30093697 PMCID: PMC6180114 DOI: 10.1038/s41386-018-0160-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Revised: 07/02/2018] [Accepted: 07/13/2018] [Indexed: 12/15/2022]
Abstract
GABAergic drugs are of interest for the treatment of anxiety, depression, bipolar disorder, pain, cognitive impairment associated with schizophrenia (CIAS), and other neuropsychiatric disorders. Some evidence suggests that TPA-023, (7-(1,1-dimethylethyl)-6-(2-ethyl-2H-1,2,4-triazol-3-ylmethoxy)-3-(2-fluorophenyl)-1,2,4-triazolo[4,3-b] pyridazine), a GABAA α2,3 subtype-selective GABAA partial agonist and α1/5 antagonist, and the neurosteroid, pregnenolone sulfate, a GABAA antagonist, may improve CIAS in pilot clinical trials. The goal of this study was to investigate the effect of TPA-023 in mice after acute or subchronic (sc) treatment with the N-methyl-D-aspartate receptor (NMDAR) antagonist, phencyclidine (PCP), on novel object recognition (NOR), reversal learning (RL), and locomotor activity (LMA) in rodents. Acute TPA-023 significantly reversed scPCP-induced NOR and RL deficits. Co-administration of sub-effective dose (SED) TPA-023 with SEDs of the atypical antipsychotic drug, lurasidone, significantly potentiated the effect of TPA-023 in reversing the scPCP-induced NOR deficit. Further, scTPA-023 co-administration significantly prevented scPCP-induced NOR deficit for 5 weeks. Also, administration of TPA-023 for 7 days following scPCP reversed the NOR deficit for 1 week. However, TPA-023 did not blunt acute PCP-induced hyperactivity, suggesting lack of efficacy as a treatment for psychosis. Systemic TPA-023 significantly blocked lurasidone-induced increases in cortical acetylcholine, dopamine, and glutamate without affecting increases in norepinephrine and with minimal effect on basal release of these neurotransmitters. TPA-023 significantly inhibited PCP-induced cortical and striatal dopamine, serotonin, norepinephrine, and glutamate efflux. These results suggest that TPA-023 and other GABAA agonists may be of benefit to treat CIAS.
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Affiliation(s)
- Lakshmi Rajagopal
- 0000 0001 2299 3507grid.16753.36Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
| | - Mei Huang
- 0000 0001 2299 3507grid.16753.36Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
| | - Eric Michael
- 0000 0001 2299 3507grid.16753.36Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
| | - Sunoh Kwon
- 0000 0001 2299 3507grid.16753.36Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
| | - Herbert Y. Meltzer
- 0000 0001 2299 3507grid.16753.36Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
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16
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Cadinu D, Grayson B, Podda G, Harte MK, Doostdar N, Neill JC. NMDA receptor antagonist rodent models for cognition in schizophrenia and identification of novel drug treatments, an update. Neuropharmacology 2018; 142:41-62. [DOI: 10.1016/j.neuropharm.2017.11.045] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 10/28/2017] [Accepted: 11/27/2017] [Indexed: 01/05/2023]
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17
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Honeycutt JA, Chrobak JJ. Parvalbumin Loss Following Chronic Sub-Anesthetic NMDA Antagonist Treatment is Age-Dependent in the Hippocampus: Implications for Modeling NMDA Hypofunction. Neuroscience 2018; 393:73-82. [DOI: 10.1016/j.neuroscience.2018.09.031] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 09/23/2018] [Indexed: 01/02/2023]
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18
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Shan L, Liu T, Zhang Z, Liu Q, Zhang M, Zhao X, Zhang Y, Xu F, Ma Y. Schizophrenia-like olfactory dysfunction induced by acute and postnatal phencyclidine exposure in rats. Schizophr Res 2018; 199:274-280. [PMID: 29510924 DOI: 10.1016/j.schres.2018.02.045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 02/22/2018] [Accepted: 02/25/2018] [Indexed: 10/17/2022]
Abstract
Deficits in olfactory abilities are frequently observed in schizophrenia patients. However, whether olfactory dysfunction is found in animal models is not known. Here, we examined whether two well-established schizophrenia rat models exhibit olfactory-relevant dysfunction that is similar to schizophrenia patients. Olfactory sensitivity was tested in rats that were acutely (3.3mg/kg) or postnatally (10mg/kg, at postnatal day 7, 9 and 11) treated with phencyclidine (PCP) as schizophrenia models. Electrophysiological recordings were conducted to measure the olfactory-relevant local field potential after acute PCP treatment. Olfactory-relevant neural connections were tested via virus tracing in rats postnatally treated with PCP. We also assessed the reversal effects of olanzapine (OLZ) treatment on both models. We found that acute PCP treatment induced a decline in olfactory sensitivity (p=0.01) and significantly lower beta- and higher gamma-band oscillations (p=0.03, and p=0.00 respectively) which were partly attenuated by OLZ treatment (2mg/kg and 4mg/kg). Postnatal PCP exposure also resulted in an olfactory sensitivity deficit during adulthood (p=0.012 for males and p=0.009 for females), and an abnormal development of neural circuits (p=0.000). Together, our research indicated that olfactory dysfunction found in schizophrenia patients can also be observed on animal models.
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Affiliation(s)
- Liang Shan
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; State Key Laboratory of Biomembrane and Membrane Biotechnology, College of Life Sciences, PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China
| | - Tiane Liu
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Zhijian Zhang
- Wuhan Institute of Physics and Mathematics, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Qing Liu
- Wuhan Institute of Physics and Mathematics, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Mengjiao Zhang
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Xudong Zhao
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Yan Zhang
- State Key Laboratory of Biomembrane and Membrane Biotechnology, College of Life Sciences, PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China
| | - Fuqiang Xu
- Wuhan Institute of Physics and Mathematics, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Wuhan 430071, China; Wuhan National Laboratory for Optoelectronics, Wuhan 430074, China
| | - Yuanye Ma
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; Yunnan Key Laboratory of Primate Biomedicine Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming 650500, China.
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19
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NMDA-receptor inhibition and oxidative stress during hippocampal maturation differentially alter parvalbumin expression and gamma-band activity. Sci Rep 2018; 8:9545. [PMID: 29934499 PMCID: PMC6015018 DOI: 10.1038/s41598-018-27830-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 06/11/2018] [Indexed: 02/06/2023] Open
Abstract
Dysfunction of parvalbumin (PV)-expressing interneurons is thought to underlie the alterations of gamma-band oscillations observed in schizophrenia. Although the pathomechanisms of this disease remain unclear, oxidative stress induced by NMDA receptor (NMDAR) hypofunction and decreased glutathione (GSH) synthesizing capacity have been shown to lead to PV-loss and aberrant oscillatory activity. However, the individual contributions of NMDAR-inhibition and GSH-depletion to the developmental alterations observed in schizophrenia are largely unknown. We therefore investigated each condition in isolation using hippocampal slice cultures wherein interneuron maturation occurs entirely in vitro. Although both treatments caused oxidative stress, NMDAR-inhibition led to an immediate reduction in gamma oscillation frequency and a delayed loss of PV. In contrast, GSH-depletion immediately decreased PV expression and increased power, without affecting frequency. Hence, although disturbances of PV-expression and gamma oscillations coexist in schizophrenia, they can arise from separate pathological processes.
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20
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Riordan AJ, Schaler AW, Fried J, Paine TA, Thornton JE. Estradiol and luteinizing hormone regulate recognition memory following subchronic phencyclidine: Evidence for hippocampal GABA action. Psychoneuroendocrinology 2018. [PMID: 29529524 DOI: 10.1016/j.psyneuen.2018.02.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The cognitive symptoms of schizophrenia are poorly understood and difficult to treat. Estrogens may mitigate these symptoms via unknown mechanisms. To examine these mechanisms, we tested whether increasing estradiol (E) or decreasing luteinizing hormone (LH) could mitigate short-term episodic memory loss in a phencyclidine (PCP) model of schizophrenia. We then assessed whether changes in cortical or hippocampal GABA may underlie these effects. Female rats were ovariectomized and injected subchronically with PCP. To modulate E and LH, animals received estradiol capsules or Antide injections. Short-term episodic memory was assessed using the novel object recognition task (NORT). Brain expression of GAD67 was analyzed via western blot, and parvalbumin-containing cells were counted using immunohistochemistry. Some rats received hippocampal infusions of a GABAA agonist, GABAA antagonist, or GAD inhibitor before behavioral testing. We found that PCP reduced hippocampal GAD67 and abolished recognition memory. Antide restored hippocampal GAD67 and rescued recognition memory in PCP-treated animals. Estradiol prevented PCP's amnesic effect in NORT but failed to restore hippocampal GAD67. PCP did not cause significant differences in number of parvalbumin-expressing cells or cortical expression of GAD67. Hippocampal infusions of a GABAA agonist restored recognition memory in PCP-treated rats. Blocking hippocampal GAD or GABAA receptors in ovx animals reproduced recognition memory loss similar to PCP and inhibited estradiol's protection of recognition memory in PCP-treated animals. In summary, decreasing LH or increasing E can lessen short-term episodic memory loss, as measured by novel object recognition, in a PCP model of schizophrenia. Alterations in hippocampal GABA may contribute to both PCP's effects on recognition memory and the hormones' ability to prevent or reverse them.
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Affiliation(s)
- Alexander J Riordan
- Oberlin College, Neuroscience Department, 119 Woodland St, Oberlin, OH 44074, USA.
| | - Ari W Schaler
- Oberlin College, Neuroscience Department, 119 Woodland St, Oberlin, OH 44074, USA
| | - Jenny Fried
- Oberlin College, Neuroscience Department, 119 Woodland St, Oberlin, OH 44074, USA
| | - Tracie A Paine
- Oberlin College, Neuroscience Department, 119 Woodland St, Oberlin, OH 44074, USA
| | - Janice E Thornton
- Oberlin College, Neuroscience Department, 119 Woodland St, Oberlin, OH 44074, USA
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21
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Ghoshal A, Moran SP, Dickerson JW, Joffe ME, Grueter BA, Xiang Z, Lindsley CW, Rook JM, Conn PJ. Role of mGlu 5 Receptors and Inhibitory Neurotransmission in M 1 Dependent Muscarinic LTD in the Prefrontal Cortex: Implications in Schizophrenia. ACS Chem Neurosci 2017; 8:2254-2265. [PMID: 28679049 DOI: 10.1021/acschemneuro.7b00167] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Selective potentiation of the mGlu5 subtype of metabotropic glutamate (mGlu) receptor using positive allosteric modulators (PAMs) has robust cognition-enhancing effects in rodent models that are relevant for schizophrenia. Until recently, these effects were thought to be due to potentiation of mGlu5-induced modulation of NMDA receptor (NMDAR) currents and NMDAR-dependent synaptic plasticity. However, "biased" mGlu5 PAMs that do not potentiate mGlu5 effects on NMDAR currents show efficacy that is similar to that of prototypical mGlu5 PAMs, suggesting that NMDAR-independent mechanisms must be involved in these actions. We now report that synaptic activation of mGlu5 is required for a form of long-term depression (mLTD) in mouse prefrontal cortex (PFC) that is induced by activation of M1 muscarinic acetylcholine (mAChR) receptors, which was previously thought to be independent of mGlu5 activation. Interestingly, a biased mGlu5 PAM, VU0409551, that does not potentiate mGlu5 modulation of NMDAR currents, potentiated induction of mLTD. Furthermore, coactivation of mGlu5 and M1 receptors increased GABAA-dependent inhibitory tone in the PFC pyramidal neurons, which likely contributes to the observed mLTD. Finally, systemic administration of the biased mGlu5 PAM reversed deficits in mLTD and associated cognitive deficits in a model of cortical disruption caused by repeated phencyclidine exposure that is relevant for schizophrenia and was previously shown to be responsive to selective M1 muscarinic receptor PAMs. These studies provide exciting new insights into a novel mechanism by which mGlu5 PAMs can reverse deficits in PFC function and cognition that is independent of modulation of NMDAR currents.
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Affiliation(s)
- Ayan Ghoshal
- Department of Pharmacology,
Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, Tennessee 37240, United States
| | - Sean P. Moran
- Department of Pharmacology,
Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, Tennessee 37240, United States
| | - Jonathan W. Dickerson
- Department of Pharmacology,
Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, Tennessee 37240, United States
| | - Max E. Joffe
- Department of Pharmacology,
Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, Tennessee 37240, United States
| | - Brad A. Grueter
- Department of Pharmacology,
Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, Tennessee 37240, United States
| | - Zixiu Xiang
- Department of Pharmacology,
Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, Tennessee 37240, United States
| | - Craig W. Lindsley
- Department of Pharmacology,
Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, Tennessee 37240, United States
| | - Jerri M. Rook
- Department of Pharmacology,
Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, Tennessee 37240, United States
| | - P. Jeffrey Conn
- Department of Pharmacology,
Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, Tennessee 37240, United States
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22
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Cardis R, Cabungcal JH, Dwir D, Do KQ, Steullet P. A lack of GluN2A-containing NMDA receptors confers a vulnerability to redox dysregulation: Consequences on parvalbumin interneurons, and their perineuronal nets. Neurobiol Dis 2017; 109:64-75. [PMID: 29024713 DOI: 10.1016/j.nbd.2017.10.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 09/11/2017] [Accepted: 10/08/2017] [Indexed: 01/06/2023] Open
Abstract
The GluN2A subunit of NMDA receptors (NMDARs) plays a critical role during postnatal brain development as its expression increases while Glun2B expression decreases. Mutations and polymorphisms in GRIN2A gene, coding for GluN2A, are linked to developmental brain disorders such as mental retardation, epilepsy, schizophrenia. Published data suggest that GluN2A is involved in maturation and phenotypic maintenance of parvalbumin interneurons (PVIs), and these interneurons suffer from a deficient glutamatergic neurotransmission via GluN2A-containing NMDARs in schizophrenia. In the present study, we find that although PVIs and their associated perineuronal nets (PNNs) appear normal in anterior cingulate cortex of late adolescent/young adult GRIN2A KO mice, a lack of GluN2A delays PNN maturation. GRIN2A KO mice display a susceptibility to redox dysregulation as sub-threshold oxidative stress and subtle alterations in antioxidant systems are observed in their prefrontal cortex. Consequently, an oxidative insult applied during early postnatal development increases oxidative stress, decreases the number of parvalbumin-immunoreactive cells, and weakens the PNNs in KO but not WT mice. These effects are long-lasting, but preventable by the antioxidant, N-acetylcysteine. The persisting oxidative stress, deficit in PVIs and PNNs, and reduced local high-frequency neuronal synchrony in anterior cingulate of late adolescent/young adult KO mice, which have been challenged by an early-life oxidative insult, is accompanied with microglia activation. Altogether, these indicate that a lack of GluN2A-containing NMDARs alters the fine control of redox status, leading to a delayed maturation of PNNs, and conferring vulnerability for long-term oxidative stress, microglial activation, and PVI network dysfunction.
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Affiliation(s)
- Romain Cardis
- Center of Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital (CHUV), Site de Cery, 1008 Prilly, Lausanne, Switzerland
| | - Jan-Harry Cabungcal
- Center of Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital (CHUV), Site de Cery, 1008 Prilly, Lausanne, Switzerland
| | - Daniella Dwir
- Center of Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital (CHUV), Site de Cery, 1008 Prilly, Lausanne, Switzerland
| | - Kim Q Do
- Center of Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital (CHUV), Site de Cery, 1008 Prilly, Lausanne, Switzerland
| | - Pascal Steullet
- Center of Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital (CHUV), Site de Cery, 1008 Prilly, Lausanne, Switzerland.
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23
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Steullet P, Cabungcal JH, Coyle J, Didriksen M, Gill K, Grace AA, Hensch TK, LaMantia AS, Lindemann L, Maynard TM, Meyer U, Morishita H, O'Donnell P, Puhl M, Cuenod M, Do KQ. Oxidative stress-driven parvalbumin interneuron impairment as a common mechanism in models of schizophrenia. Mol Psychiatry 2017; 22:936-943. [PMID: 28322275 PMCID: PMC5491690 DOI: 10.1038/mp.2017.47] [Citation(s) in RCA: 234] [Impact Index Per Article: 33.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 12/21/2016] [Accepted: 01/17/2017] [Indexed: 02/08/2023]
Abstract
Parvalbumin inhibitory interneurons (PVIs) are crucial for maintaining proper excitatory/inhibitory balance and high-frequency neuronal synchronization. Their activity supports critical developmental trajectories, sensory and cognitive processing, and social behavior. Despite heterogeneity in the etiology across schizophrenia and autism spectrum disorder, PVI circuits are altered in these psychiatric disorders. Identifying mechanism(s) underlying PVI deficits is essential to establish treatments targeting in particular cognition. On the basis of published and new data, we propose oxidative stress as a common pathological mechanism leading to PVI impairment in schizophrenia and some forms of autism. A series of animal models carrying genetic and/or environmental risks relevant to diverse etiological aspects of these disorders show PVI deficits to be all accompanied by oxidative stress in the anterior cingulate cortex. Specifically, oxidative stress is negatively correlated with the integrity of PVIs and the extracellular perineuronal net enwrapping these interneurons. Oxidative stress may result from dysregulation of systems typically affected in schizophrenia, including glutamatergic, dopaminergic, immune and antioxidant signaling. As convergent end point, redox dysregulation has successfully been targeted to protect PVIs with antioxidants/redox regulators across several animal models. This opens up new perspectives for the use of antioxidant treatments to be applied to at-risk individuals, in close temporal proximity to environmental impacts known to induce oxidative stress.
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Affiliation(s)
- P Steullet
- Centre for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital, Prilly-Lausanne, Switzerland
| | - J-H Cabungcal
- Centre for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital, Prilly-Lausanne, Switzerland
| | - J Coyle
- Laboratory for Psychiatric and Molecular Neuroscience, Harvard Medical School, McLean Hospital, Belmont, MA, USA
| | - M Didriksen
- Synaptic transmission H. Lundbeck A/S, Valby, Denmark
| | - K Gill
- Departments of Neuroscience, Psychiatry and Psychology, University of Pittsburgh, Pittsburgh, PA, USA
| | - A A Grace
- Departments of Neuroscience, Psychiatry and Psychology, University of Pittsburgh, Pittsburgh, PA, USA
| | - T K Hensch
- Center for Brain Science, Department of Molecular Cellular Biology, Harvard University, Cambridge, MA USA,FM Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
| | - A-S LaMantia
- George Washington Institute for Neuroscience, The George Washington University, Washington, DC, USA
| | - L Lindemann
- F. Hoffmann-La Roche, Roche Pharmaceutical and Early Development, Neuroscience, Opthalmology & Rare Disease (NORD) DTA, Discovery Neuroscience, Roche Innovation Center Basel, Basel, Switzerland
| | - T M Maynard
- George Washington Institute for Neuroscience, The George Washington University, Washington, DC, USA
| | - U Meyer
- Institute of Pharmacology and Toxicology, University of Zurich-Vetsuisse, Zurich, Switzerland
| | - H Morishita
- Center for Brain Science, Department of Molecular Cellular Biology, Harvard University, Cambridge, MA USA,FM Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA,Department of Psychiatry, Neuroscience, and Ophthalmology, Friedman Brain Institute, Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, NY, USA
| | - P O'Donnell
- Neuroscience and Pain Research Unit, BioTherapeutics Research and Development, Pfizer, Cambridge, MA, USA
| | - M Puhl
- Laboratory for Psychiatric and Molecular Neuroscience, Harvard Medical School, McLean Hospital, Belmont, MA, USA
| | - M Cuenod
- Centre for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital, Prilly-Lausanne, Switzerland
| | - K Q Do
- Centre for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital, Prilly-Lausanne, Switzerland,Center for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital, Prilly-Lausanne CH-1008, Switzerland. E-mail:
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Bastrup J, Larsen PH. Optimized CLARITY technique detects reduced parvalbumin density in a genetic model of schizophrenia. J Neurosci Methods 2017; 283:23-32. [PMID: 28342832 DOI: 10.1016/j.jneumeth.2017.03.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 03/16/2017] [Accepted: 03/18/2017] [Indexed: 01/05/2023]
Abstract
BACKGROUND Novel tissue clearing technologies have, for the first time, made it possible to study intact tissue samples. This approach provides a tool for further clarifying findings from animal models of schizophrenia by studying parvalbumin-positive (PV+) interneuron density from a 3D perspective. NEW METHOD This study has developed an optimised CLARITY protocol, including an improved electrophoretic tissue clearing (ETC) chamber, an evaluation of antibody diffusion into cleared tissue slices, and a computational method for detecting PV+ interneurons in 3D. RESULTS A reduced PV+ interneuron density was found in both prelimbic and motor cortex regions of the Df(h15q13)/+ mice, while no changes were observed in the Df(h22q11)/+ mice. COMPARISON WITH EXISTING METHOD The developed ETC chamber enables tissue clearing of variable tissue sizes while minimizing the resistance. It was found that a high concentration of primary and secondary antibodies were necessary for sufficient antibody staining of PV+ interneurons. Additionally, the developed computational method showed improved detection rates of interneurons compared to non-processed image stacks. CONCLUSION Our optimization of the CLARITY technology and automated 3D counting of cells were found to be useful for quantification of PV+ interneuron density. The results may provide insight into understanding the pathophysiology underlying the phenotype observed in Df(h15q13)/+ mice.
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Affiliation(s)
- Joakim Bastrup
- Department of Synaptic transmission, H. Lundbeck A/S, Ottiliavej 7, 2500 Valby, Denmark.
| | - Peter H Larsen
- Department of Synaptic transmission, H. Lundbeck A/S, Ottiliavej 7, 2500 Valby, Denmark.
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Neuroinflammation and Oxidative Stress in Psychosis and Psychosis Risk. Int J Mol Sci 2017; 18:ijms18030651. [PMID: 28304340 PMCID: PMC5372663 DOI: 10.3390/ijms18030651] [Citation(s) in RCA: 109] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 03/07/2017] [Accepted: 03/15/2017] [Indexed: 12/18/2022] Open
Abstract
Although our understanding of psychotic disorders has advanced substantially in the past few decades, very little has changed in the standard of care for these illnesses since the development of atypical anti-psychotics in the 1990s. Here, we integrate new insights into the pathophysiology with the increasing interest in early detection and prevention. First, we explore the role of N-methyl-d-aspartate receptors in a subpopulation of cortical parvalbumin-containing interneurons (PVIs). Postmortem and preclinical data has implicated these neurons in the positive and negative symptoms, as well as the cognitive dysfunction present in schizophrenia. These neurons also appear to be sensitive to inflammation and oxidative stress during the perinatal and peripubertal periods, which may be mediated in large part by aberrant synaptic pruning. After exploring some of the molecular mechanisms through which neuroinflammation and oxidative stress are thought to exert their effects, we highlight the progress that has been made in identifying psychosis prior to onset through the identification of individuals at clinical high risk for psychosis (CHR). By combining our understanding of psychosis pathogenesis with the increasing characterization of endophenotypes that precede frank psychosis, it may be possible to identify patients before they present with psychosis and intervene to reduce the burden of the disease to both patients and families.
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NMDAR hypofunction and somatostatin-expressing GABAergic interneurons and receptors: A newly identified correlation and its effects in schizophrenia. SCHIZOPHRENIA RESEARCH-COGNITION 2017; 8:1-6. [PMID: 28740825 PMCID: PMC5514309 DOI: 10.1016/j.scog.2017.02.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/08/2016] [Revised: 02/21/2017] [Accepted: 02/22/2017] [Indexed: 12/20/2022]
Abstract
This review investigates the association between N-methyl-d-Aspartate receptor (NMDAR) hypofunction and somatostatin-expressing GABAergic interneurons (SST +) and how it contributes to the cognitive deficits observed in schizophrenia (SZ). This is based on evidence that NMDAR antagonists caused symptoms resembling SZ in healthy individuals. NMDAR hypofunction in GABAergic interneurons results in the modulation of the cortical network oscillation, particularly in the gamma range (30–80 Hz). These gamma-band oscillation (GBO) abnormalities were found to lead to the cognitive deficits observed in the disorder. Postmortem mRNA studies have shown that SST decreased more significantly than any other biomarker in schizophrenic subjects. The functional role of Somatostatin (SST) in the aetiology of SZ can be studied through its receptors. Genetic knockout studies in animal models in Huntington's disease (HD) have shown that a specific SST receptor, SSTR2, is increased along with the increased NMDAR activity, with opposing patterns observed in SZ. A direct correlation between SSTR and NMDAR is hence inferred in this review with the hope of finding a potential new therapeutic target for the treatment of SZ and related neurological conditions.
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Nakazawa K, Jeevakumar V, Nakao K. Spatial and temporal boundaries of NMDA receptor hypofunction leading to schizophrenia. NPJ SCHIZOPHRENIA 2017; 3:7. [PMID: 28560253 PMCID: PMC5441533 DOI: 10.1038/s41537-016-0003-3] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/09/2016] [Revised: 11/17/2016] [Accepted: 11/22/2016] [Indexed: 12/21/2022]
Abstract
The N-methyl-d-aspartate receptor hypofunction is one of the most prevalent models of schizophrenia. For example, healthy subjects treated with uncompetitive N-methyl-d-aspartate receptor antagonists elicit positive, negative, and cognitive-like symptoms of schizophrenia. Patients with anti-N-methyl-d-aspartate receptor encephalitis, which is likely caused by autoantibody-mediated down-regulation of cell surface N-methyl-d-aspartate receptors, often experience psychiatric symptoms similar to schizophrenia initially. However, where and when N-methyl-d-aspartate receptor hypofunction occurs in the brain of schizophrenic patients is poorly understood. Here we review the findings from N-methyl-d-aspartate receptor antagonist and autoantibody models, postmortem studies on N-methyl-d-aspartate receptor subunits, as well as the global and cell-type-specific knockout mouse models of subunit GluN1. We compare various conditional GluN1 knockout mouse strains, focusing on the onset of N-methyl-d-aspartate receptor deletion and on the cortical cell-types. Based on these results, we hypothesize that N-methyl-d-aspartate receptor hypofunction initially occurs in cortical GABAergic neurons during early postnatal development. The resulting GABA neuron maturation deficit may cause reduction of intrinsic excitability and GABA release, leading to disinhibition of pyramidal neurons. The cortical disinhibition in turn could elicit glutamate spillover and subsequent homeostatic down regulation of N-methyl-d-aspartate receptor function in pyramidal neurons in prodromal stage. These two temporally-distinct N-methyl-d-aspartate receptor hypofunctions may be complimentary, as neither alone may not be able to fully explain the entire schizophrenia pathophysiology. Potential underlying mechanisms for N-methyl-d-aspartate receptor hypofunction in cortical GABA neurons are also discussed, based on studies of naturally-occurring N-methyl-d-aspartate receptor antagonists, neuregulin/ErbB4 signaling pathway, and theoretical analysis of excitatory/inhibitory balance.
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Affiliation(s)
- Kazu Nakazawa
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL USA
| | - Vivek Jeevakumar
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL USA
| | - Kazuhito Nakao
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL USA
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Gaskin PL, Toledo-Rodriguez M, Alexander SP, Fone KC. Down-Regulation of Hippocampal Genes Regulating Dopaminergic, GABAergic, and Glutamatergic Function Following Combined Neonatal Phencyclidine and Post-Weaning Social Isolation of Rats as a Neurodevelopmental Model for Schizophrenia. Int J Neuropsychopharmacol 2016; 19:pyw062. [PMID: 27382048 PMCID: PMC5137279 DOI: 10.1093/ijnp/pyw062] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 06/27/2016] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Dysfunction of dopaminergic, GABAergic, and glutamatergic function underlies many core symptoms of schizophrenia. Combined neonatal injection of the N-methyl-D-aspartate (NMDA) receptor antagonist, phencyclidine (PCP), and post-weaning social isolation of rats produces a behavioral syndrome with translational relevance to several core symptoms of schizophrenia. This study uses DNA microarray to characterize alterations in hippocampal neurotransmitter-related gene expression and examines the ability of the sodium channel blocker, lamotrigine, to reverse behavioral changes in this model. METHODS Fifty-four male Lister-hooded rat pups either received phencyclidine (PCP, 10mg/kg, s.c.) on post-natal days (PND) 7, 9, and 11 before being weaned on PND 23 into separate cages (isolation; PCP-SI; n = 31) or received vehicle injection and group-housing (2-4 per cage; V-GH; n = 23) from weaning. The effect of lamotrigine on locomotor activity, novel object recognition, and prepulse inhibition of acoustic startle was examined (PND 60-75) and drug-free hippocampal gene expression on PND 70. RESULTS Acute lamotrigine (10-15mg/kg i.p.) reversed the hyperactivity and novel object recognition impairment induced by PCP-SI but had no effect on the prepulse inhibition deficit. Microarray revealed small but significant down-regulation of hippocampal genes involved in glutamate metabolism, dopamine neurotransmission, and GABA receptor signaling and in specific schizophrenia-linked genes, including parvalbumin (PVALB) and GAD67, in PCP-SI rats, which resemble changes reported in schizophrenia. CONCLUSIONS Findings indicate that alterations in dopamine neurotransmission, glutamate metabolism, and GABA signaling may contribute to some of the behavioral deficits observed following PCP-SI, and that lamotrigine may have some utility as an adjunctive therapy to improve certain cognitive deficits symptoms in schizophrenia.
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Affiliation(s)
- Philip Lr Gaskin
- School of Life Sciences, Medical School, Queen's Medical Centre, The University of Nottingham, United Kingdom (Drs Gaskin, Toledo-Rodriguez, Alexander, and Fone)
| | - Maria Toledo-Rodriguez
- School of Life Sciences, Medical School, Queen's Medical Centre, The University of Nottingham, United Kingdom (Drs Gaskin, Toledo-Rodriguez, Alexander, and Fone)
| | - Stephen Ph Alexander
- School of Life Sciences, Medical School, Queen's Medical Centre, The University of Nottingham, United Kingdom (Drs Gaskin, Toledo-Rodriguez, Alexander, and Fone)
| | - Kevin Cf Fone
- School of Life Sciences, Medical School, Queen's Medical Centre, The University of Nottingham, United Kingdom (Drs Gaskin, Toledo-Rodriguez, Alexander, and Fone)
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Steullet P, Cabungcal JH, Monin A, Dwir D, O'Donnell P, Cuenod M, Do KQ. Redox dysregulation, neuroinflammation, and NMDA receptor hypofunction: A "central hub" in schizophrenia pathophysiology? Schizophr Res 2016; 176:41-51. [PMID: 25000913 PMCID: PMC4282982 DOI: 10.1016/j.schres.2014.06.021] [Citation(s) in RCA: 171] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Revised: 06/06/2014] [Accepted: 06/08/2014] [Indexed: 12/18/2022]
Abstract
Accumulating evidence points to altered GABAergic parvalbumin-expressing interneurons and impaired myelin/axonal integrity in schizophrenia. Both findings could be due to abnormal neurodevelopmental trajectories, affecting local neuronal networks and long-range synchrony and leading to cognitive deficits. In this review, we present data from animal models demonstrating that redox dysregulation, neuroinflammation and/or NMDAR hypofunction (as observed in patients) impairs the normal development of both parvalbumin interneurons and oligodendrocytes. These observations suggest that a dysregulation of the redox, neuroimmune, and glutamatergic systems due to genetic and early-life environmental risk factors could contribute to the anomalies of parvalbumin interneurons and white matter in schizophrenia, ultimately impacting cognition, social competence, and affective behavior via abnormal function of micro- and macrocircuits. Moreover, we propose that the redox, neuroimmune, and glutamatergic systems form a "central hub" where an imbalance within any of these "hub" systems leads to similar anomalies of parvalbumin interneurons and oligodendrocytes due to the tight and reciprocal interactions that exist among these systems. A combination of vulnerabilities for a dysregulation within more than one of these systems may be particularly deleterious. For these reasons, molecules, such as N-acetylcysteine, that possess antioxidant and anti-inflammatory properties and can also regulate glutamatergic transmission are promising tools for prevention in ultra-high risk patients or for early intervention therapy during the first stages of the disease.
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Affiliation(s)
- P Steullet
- Center for Psychiatric Neuroscience, Department of Psychiatry, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Site de Cery, 1008 Prilly-Lausanne, Switzerland
| | - J H Cabungcal
- Center for Psychiatric Neuroscience, Department of Psychiatry, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Site de Cery, 1008 Prilly-Lausanne, Switzerland
| | - A Monin
- Center for Psychiatric Neuroscience, Department of Psychiatry, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Site de Cery, 1008 Prilly-Lausanne, Switzerland
| | - D Dwir
- Center for Psychiatric Neuroscience, Department of Psychiatry, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Site de Cery, 1008 Prilly-Lausanne, Switzerland
| | - P O'Donnell
- Neuroscience Research Unit, Pfizer, Inc., 700 Main Street, Cambridge, MA 02139, USA
| | - M Cuenod
- Center for Psychiatric Neuroscience, Department of Psychiatry, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Site de Cery, 1008 Prilly-Lausanne, Switzerland
| | - K Q Do
- Center for Psychiatric Neuroscience, Department of Psychiatry, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Site de Cery, 1008 Prilly-Lausanne, Switzerland.
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Sex differences in animal models of schizophrenia shed light on the underlying pathophysiology. Neurosci Biobehav Rev 2016; 67:41-56. [DOI: 10.1016/j.neubiorev.2015.10.014] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 09/28/2015] [Accepted: 10/26/2015] [Indexed: 12/20/2022]
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31
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Ji MH, Wang ZY, Sun XR, Tang H, Zhang H, Jia M, Qiu LL, Zhang GF, Peng YG, Yang JJ. Repeated Neonatal Sevoflurane Exposure-Induced Developmental Delays of Parvalbumin Interneurons and Cognitive Impairments Are Reversed by Environmental Enrichment. Mol Neurobiol 2016; 54:3759-3770. [DOI: 10.1007/s12035-016-9943-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 05/26/2016] [Indexed: 01/13/2023]
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Prenatal phencyclidine treatment induces behavioral deficits through impairment of GABAergic interneurons in the prefrontal cortex. Psychopharmacology (Berl) 2016; 233:2373-81. [PMID: 27095448 DOI: 10.1007/s00213-016-4288-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 04/01/2016] [Indexed: 10/21/2022]
Abstract
RATIONALE We previously reported that prenatal treatment with phencyclidine (PCP) induces glutamatergic dysfunction in the prefrontal cortex (PFC), leading to schizophrenia-like behavioral deficits in adult mice. However, little is known about the prenatal effect of PCP treatment on other types of neurons. OBJECTIVES We focused on γ-aminobutyric acid (GABA)-ergic interneurons and evaluated the effect of prenatal PCP exposure on the neurodevelopment of GABAergic interneurons in the PFC. METHODS PCP was administered at the dose of 10 mg/kg/day to pregnant dams from embryonic day 6.5 to 18.5. After the pups were reared to adult, we analyzed their GABAergic system in the PFC using immunohistological, biochemical, and behavioral analyses in adulthood. RESULTS The prenatal PCP treatment decreased the density of parvalbumin-positive cells and reduced the expression level of glutamic acid decarboxylase 67 (GAD67) and GABA content of the PFC in adults. Additionally, prenatal PCP treatment induced behavioral deficits in adult mice, such as hypersensitivity to PCP and prepulse inhibition (PPI) deficits. These behavioral deficits were ameliorated by pretreatment with the GABAB receptor agonist baclofen. Furthermore, the density of c-Fos-positive cells was decreased after the PPI test in the PFC of mice treated with PCP prenatally, and this effect was ameliorated by pretreatment with baclofen. CONCLUSIONS These findings suggest that prenatal treatment with PCP induced GABAergic dysfunction in the PFC, which caused behavioral deficits.
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Dong C, Rovnaghi CR, Anand KJS. Ketamine exposure during embryogenesis inhibits cellular proliferation in rat fetal cortical neurogenic regions. Acta Anaesthesiol Scand 2016; 60:579-87. [PMID: 26822861 DOI: 10.1111/aas.12689] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Revised: 11/19/2015] [Accepted: 11/30/2015] [Indexed: 01/01/2023]
Abstract
BACKGROUND Developmental neurotoxicity of ketamine, an N-methyl-D-aspartate receptor antagonist, must be considered due to its widespread uses for sedation/analgesia/anesthesia in pediatric and obstetric settings. Dose-dependent effects of ketamine on cellular proliferation in the neurogenic regions of rat fetal cortex [ventricular zone (VZ) and subventricular zone (SVZ)] were investigated in this in vivo study. METHODS Timed-pregnant Sprague-Dawley rats at embryonic day 17 (E17) were given with different doses of ketamine intraperitoneally (0, 1, 2, 10, 20, 40, and 100 mg/kg). Proliferating cells in the rat fetal brains were labeled by injecting 100 mg/kg of 5-bromo-2'-deoxyuridine (BrdU) intraperitoneally. BrdU-labeled cells were detected by immunostaining methods. The numbers of BrdU-positive cells in VZ and SVZ of rat fetal cortex were employed to quantify proliferation in the developing rat cortex. RESULTS Ketamine dose-dependently reduced the number of BrdU-positive cells in VZ (P < 0.001) and SVZ (P < 0.001) of the rat fetal cortex. SVZ showed greater susceptibility to ketamine-induced reduction of proliferation in rat fetal cortex, occurring even at clinically relevant doses (2 mg/kg). CONCLUSION These data suggest that exposure to ketamine during embryogenesis can dose-dependently inhibit the cellular proliferation in neurogenic regions of the rat fetal cortex.
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Affiliation(s)
- C. Dong
- Department of Anesthesiology; The Second Affiliated Hospital & Yuying Children's Hospital of Wenzhou Medical University; Wenzhou Zhejiang China
- Department of Pediatrics; University of Tennessee Health Science Center; Memphis TN USA
- Department of Anatomy and Neurobiology; Neuroscience Institute; University of Tennessee Health Science Center; Memphis TN USA
| | - C. R. Rovnaghi
- Department of Pediatrics; University of Tennessee Health Science Center; Memphis TN USA
- Department of Anatomy and Neurobiology; Neuroscience Institute; University of Tennessee Health Science Center; Memphis TN USA
| | - K. J. S. Anand
- Department of Pediatrics; University of Tennessee Health Science Center; Memphis TN USA
- Department of Anatomy and Neurobiology; Neuroscience Institute; University of Tennessee Health Science Center; Memphis TN USA
- Department of Pediatrics; Stanford University School of Medicine; Palo Alto CA USA
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Li JT, Su YA, Wang HL, Zhao YY, Liao XM, Wang XD, Si TM. Repeated Blockade of NMDA Receptors During Adolescence Impairs Reversal Learning and Disrupts GABAergic Interneurons in Rat Medial Prefrontal Cortex. Front Mol Neurosci 2016; 9:17. [PMID: 26973457 PMCID: PMC4776083 DOI: 10.3389/fnmol.2016.00017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 02/19/2016] [Indexed: 11/13/2022] Open
Abstract
Adolescence is of particular significance to schizophrenia, since psychosis onset typically occurs in this critical period. Based on the N-methyl-D-aspartate (NMDA) receptor hypofunction hypothesis of schizophrenia, in this study, we investigated whether and how repeated NMDA receptor blockade during adolescence would affect GABAergic interneurons in rat medial prefrontal cortex (mPFC) and mPFC-mediated cognitive functions. Specifically, adolescent rats were subjected to intraperitoneal administration of MK-801 (0.1, 0.2, 0.4 mg/kg), a non-competitive NMDA receptor antagonist, for 14 days and then tested for reference memory and reversal learning in the water maze. The density of parvabumin (PV)-, calbindin (CB)- and calretinin (CR)-positive neurons in mPFC was analyzed at either 24 h or 7 days after drug cessation. We found that MK-801 treatment delayed reversal learning in the water maze without affecting initial acquisition. Strikingly, MK-801 treatment also significantly reduced the density of PV+ and CB+ neurons, and this effect persisted for 7 days after drug cessation at the dose of 0.2 mg/kg. We further demonstrated that the reduction in PV+ and CB+ neuron densities was ascribed to a downregulation of the expression levels of PV and CB, but not to neuronal death. These results parallel the behavioral and neuropathological changes of schizophrenia and provide evidence that adolescent NMDA receptors antagonism offers a useful tool for unraveling the etiology of the disease.
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Affiliation(s)
- Ji-Tao Li
- National Clinical Research Center for Mental Disorders, (Peking University Sixth Hospital/Institute of Mental Health) and the Key Laboratory of Mental Health, Ministry of Health (Peking University) Beijing, China
| | - Yun-Ai Su
- National Clinical Research Center for Mental Disorders, (Peking University Sixth Hospital/Institute of Mental Health) and the Key Laboratory of Mental Health, Ministry of Health (Peking University) Beijing, China
| | - Hong-Li Wang
- National Clinical Research Center for Mental Disorders, (Peking University Sixth Hospital/Institute of Mental Health) and the Key Laboratory of Mental Health, Ministry of Health (Peking University) Beijing, China
| | - Ying-Ying Zhao
- Depression Treatment Center, Beijing Anding Hospital of Capital Medical University Beijing, China
| | - Xue-Mei Liao
- National Clinical Research Center for Mental Disorders, (Peking University Sixth Hospital/Institute of Mental Health) and the Key Laboratory of Mental Health, Ministry of Health (Peking University) Beijing, China
| | - Xiao-Dong Wang
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Ministry of Health of China, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine Hangzhou, China
| | - Tian-Mei Si
- National Clinical Research Center for Mental Disorders, (Peking University Sixth Hospital/Institute of Mental Health) and the Key Laboratory of Mental Health, Ministry of Health (Peking University) Beijing, China
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Interneuron Transcriptional Dysregulation Causes Frequency-Dependent Alterations in the Balance of Inhibition and Excitation in Hippocampus. J Neurosci 2016; 35:15276-90. [PMID: 26586816 DOI: 10.1523/jneurosci.1834-15.2015] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED Circuit dysfunction in complex brain disorders such as schizophrenia and autism is caused by imbalances between inhibitory and excitatory synaptic transmission (I/E). Short-term plasticity differentially alters responses from excitatory and inhibitory synapses, causing the I/E ratio to change as a function of frequency. However, little is known about I/E ratio dynamics in complex brain disorders. Transcriptional dysregulation in interneurons, particularly parvalbumin interneurons, is a consistent pathophysiological feature of schizophrenia. Peroxisome proliferator activated receptor γ coactivator 1α (PGC-1α) is a transcriptional coactivator that in hippocampus is highly concentrated in inhibitory interneurons and regulates parvalbumin transcription. Here, we used PGC-1α(-/-) mice to investigate effects of interneuron transcriptional dysregulation on the dynamics of the I/E ratio at the synaptic and circuit level in hippocampus. We find that loss of PGC-1α increases the I/E ratio onto CA1 pyramidal cells in response to Schaffer collateral stimulation in slices from young adult mice. The underlying mechanism is enhanced basal inhibition, including increased inhibition from parvalbumin interneurons. This decreases the spread of activation in CA1 and dramatically limits pyramidal cell spiking, reducing hippocampal output. The I/E ratio and CA1 output are partially restored by paired-pulse stimulation at short intervals, indicating frequency-dependent effects. However, circuit dysfunction persists, indicated by alterations in kainate-induced gamma oscillations and impaired nest building. Together, these results show that transcriptional dysregulation in hippocampal interneurons causes frequency-dependent alterations in I/E ratio and circuit function, suggesting that PGC-1α deficiency in psychiatric and neurological disorders contributes to disease by causing functionally relevant alterations in I/E balance. SIGNIFICANCE STATEMENT Alteration in the inhibitory and excitatory synaptic transmission (I/E) balance is a fundamental principle underlying the circuit dysfunction observed in many neuropsychiatric and neurodevelopmental disorders. The I/E ratio is dynamic, continuously changing because of synaptic short-term plasticity. We show here that transcriptional dysregulation in interneurons, particularly parvalbumin interneurons, causes frequency-dependent alterations in the I/E ratio and in circuit function in hippocampus. Peroxisome proliferator activated receptor γ coactivator 1α (PGC-1α-deficient) mice have enhanced inhibition in CA1, the opposite of what is seen in cortex. This study fills an important gap in current understanding of how changes in inhibition in complex brain disorders affect I/E dynamics, leading to region-specific circuit dysfunction and behavioral impairment. This study also provides a conceptual framework for analyzing the effects of short-term plasticity on the I/E balance in disease models.
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Grayson B, Barnes SA, Markou A, Piercy C, Podda G, Neill JC. Postnatal Phencyclidine (PCP) as a Neurodevelopmental Animal Model of Schizophrenia Pathophysiology and Symptomatology: A Review. Curr Top Behav Neurosci 2016; 29:403-428. [PMID: 26510740 DOI: 10.1007/7854_2015_403] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Cognitive dysfunction and negative symptoms of schizophrenia remain an unmet clinical need. Therefore, it is essential that new treatments and approaches are developed to recover the cognitive and social impairments that are seen in patients with schizophrenia. These may only be discovered through the use of carefully validated, aetiologically relevant and translational animal models. With recent renewed interest in the neurodevelopmental hypothesis of schizophrenia, postnatal administration of N-methyl-D-aspartate receptor (NMDAR) antagonists such as phencyclidine (PCP) has been proposed as a model that can mimic aspects of schizophrenia pathophysiology. The purpose of the current review is to examine the validity of this model and compare it with the adult subchronic PCP model. We review the ability of postnatal PCP administration to produce behaviours (specifically cognitive deficits) and neuropathology of relevance to schizophrenia and their subsequent reversal by pharmacological treatments. We review studies investigating effects of postnatal PCP on cognitive domains in schizophrenia in rats. Morris water maze and delayed spontaneous alternation tasks have been used for working memory, attentional set-shifting for executive function, social novelty discrimination for selective attention and prepulse inhibition of acoustic startle for sensorimotor gating. In addition, we review studies on locomotor activity and neuropathology. We also include two studies using dual hit models incorporating postnatal PCP and two studies on social behaviour deficits following postnatal PCP. Overall, the evidence we provide supports the use of postnatal PCP to model cognitive and neuropathological disturbances of relevance to schizophrenia. To date, there is a lack of evidence to support a significant advantage of postnatal PCP over the adult subchronic PCP model and full advantage has not been taken of its neurodevelopmental component. When thoroughly characterised, it is likely that it will provide a useful neurodevelopmental model to complement other models such as maternal immune activation, particularly when combined with other manipulations to produce dual or triple hit models. However, the developmental trajectory of behavioural and neuropathological changes induced by postnatal PCP and their relevance to schizophrenia must be carefully mapped out. Overall, we support further development of dual (or triple) hit models incorporating genetic, neurodevelopmental and appropriate environmental elements in the search for more aetiologically valid animal models of schizophrenia and neurodevelopmental disorders (NDDs).
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Affiliation(s)
- B Grayson
- Manchester Pharmacy School, University of Manchester, Oxford Road, Manchester, M13 9PT, UK.
| | - S A Barnes
- Department of Psychiatry, University of California San Diego, 9500 Gilman Drive, La Jolla, San Diego, CA, 92093-0603, USA
| | - A Markou
- Department of Psychiatry, University of California San Diego, 9500 Gilman Drive, La Jolla, San Diego, CA, 92093-0603, USA
| | - C Piercy
- Manchester Pharmacy School, University of Manchester, Oxford Road, Manchester, M13 9PT, UK
| | - G Podda
- Manchester Pharmacy School, University of Manchester, Oxford Road, Manchester, M13 9PT, UK
| | - J C Neill
- Manchester Pharmacy School, University of Manchester, Oxford Road, Manchester, M13 9PT, UK
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Perez SM, Aguilar DD, Neary JL, Carless MA, Giuffrida A, Lodge DJ. Schizophrenia-Like Phenotype Inherited by the F2 Generation of a Gestational Disruption Model of Schizophrenia. Neuropsychopharmacology 2016; 41:477-86. [PMID: 26068729 PMCID: PMC5130123 DOI: 10.1038/npp.2015.169] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 06/08/2015] [Accepted: 06/09/2015] [Indexed: 01/13/2023]
Abstract
Both environmental and genetic factors contribute to schizophrenia; however, the exact etiology of this disorder is not known. Animal models are utilized to better understand the mechanisms associated with neuropsychiatric diseases, including schizophrenia. One of these involves gestational administration of methylazoxymethanol acetate (MAM) to induce a developmental disruption, which in turn produces a schizophrenia-like phenotype in post-pubertal rats. The mechanisms by which MAM produces this phenotype are not clear; however, we now demonstrate that MAM induces differential DNA methylation, which may be heritable. Here we demonstrate that a subset of both second (F2) and third (F3) filial generations of MAM-treated rats displays a schizophrenia-like phenotype and hypermethylation of the transcription factor, Sp5. Specifically, ventral tegmental area of dopamine neuron activity was examined using electrophysiology as a correlate for the dopamine hyperfunction thought to underlie psychosis in patients. Interestingly, only a subset of F2 and F3 MAM rats exhibited increases in dopamine neuron population activity, indicating that this may be a unique model with a susceptibility to develop a schizophrenia-like phenotype. An increase in dopamine system function in rodent models has been previously associated with decreases in hippocampal GABAergic transmission. In line with these observations, we found a significant correlation between hippocampal parvalbumin expression and dopamine neuron activity in F2 rats. These data therefore provide evidence that offspring born from MAM-treated rats possess a susceptibility to develop aspects of a schizophrenia-like phenotype and may provide a useful tool to investigate gene-environment interactions.
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Affiliation(s)
- Stephanie M Perez
- Department of Pharmacology, Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - David D Aguilar
- Department of Pharmacology, Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Jennifer L Neary
- Department of Genetics, Texas Biomedical Research Institute, San Antonio, TX, USA
| | - Melanie A Carless
- Department of Genetics, Texas Biomedical Research Institute, San Antonio, TX, USA
| | - Andrea Giuffrida
- Department of Pharmacology, Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Daniel J Lodge
- Department of Pharmacology, Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
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Li JT, Zhao YY, Wang HL, Wang XD, Su YA, Si TM. Long-term effects of neonatal exposure to MK-801 on recognition memory and excitatory–inhibitory balance in rat hippocampus. Neuroscience 2015; 308:134-43. [DOI: 10.1016/j.neuroscience.2015.09.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 08/28/2015] [Accepted: 09/01/2015] [Indexed: 01/25/2023]
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Korpi ER, den Hollander B, Farooq U, Vashchinkina E, Rajkumar R, Nutt DJ, Hyytiä P, Dawe GS. Mechanisms of Action and Persistent Neuroplasticity by Drugs of Abuse. Pharmacol Rev 2015; 67:872-1004. [DOI: 10.1124/pr.115.010967] [Citation(s) in RCA: 101] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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Troudet R, Detrait E, Hanon E, Lamberty Y. Optimization and pharmacological validation of a set-shifting procedure for assessing executive function in rats. J Neurosci Methods 2015; 268:182-8. [PMID: 26296285 DOI: 10.1016/j.jneumeth.2015.08.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 08/10/2015] [Accepted: 08/11/2015] [Indexed: 01/20/2023]
Abstract
BACKGROUND Set-shifting tests represent a reliable paradigm to assess executive functions in humans and animals. In the rat, set-shifting in a cross-maze is a recognized method. In this test, rats must learn an egocentric rule to locate food reinforcement. Once acquired, a second rule, based on visual-cue strategy, allows the location of the food. Ability of rats to shift from the first to the second rule is considered to reflect cognitive flexibility. NEW METHOD This study aimed at optimizing the most currently used set-shifting protocol in a cross-maze for standardized drug testing by modulating the parameters related to caloric restriction, reward preference, and by redefining the notion of turn bias and classification of errors sub-types, i.e. perseverative vs. regressive. The new protocol has then been used to assess rats treated by sub-chronic phencyclidine administration and investigate the potential reversal effect of tolcapone, a brain penetrant catechol-O-methyl transferase inhibitor. RESULTS The new procedure resulted in a decreased total duration and a re-definition of turn bias and error subtypes. Despite preferences for sweet rewards, caloric restriction had to be maintained to motivate animals. Overall, sub-chronic PCP-treated rats made mostly perseverative errors compared to controls and required more trials to shift between the two rules. Tolcapone partly reversed impairments observed in PCP-treated rats. CONCLUSION The new protocol has improved the reliability of key parameters and has contributed to the decrease of the test duration. PCP-treated rats submitted to this protocol have been shown to have significant deficits that could be reversed by tolcapone.
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Affiliation(s)
- R Troudet
- UCB Biopharma, Neuroscience Therapeutic Area, B-1420 Braine-l'Alleud, Belgium
| | - E Detrait
- UCB Biopharma, Neuroscience Therapeutic Area, B-1420 Braine-l'Alleud, Belgium
| | - E Hanon
- UCB Biopharma, Neuroscience Therapeutic Area, B-1420 Braine-l'Alleud, Belgium
| | - Y Lamberty
- UCB Biopharma, Neuroscience Therapeutic Area, B-1420 Braine-l'Alleud, Belgium.
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Kann O. The interneuron energy hypothesis: Implications for brain disease. Neurobiol Dis 2015; 90:75-85. [PMID: 26284893 DOI: 10.1016/j.nbd.2015.08.005] [Citation(s) in RCA: 150] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 07/22/2015] [Accepted: 08/12/2015] [Indexed: 12/12/2022] Open
Abstract
Fast-spiking, inhibitory interneurons - prototype is the parvalbumin-positive (PV+) basket cell - generate action potentials at high frequency and synchronize the activity of numerous excitatory principal neurons, such as pyramidal cells, during fast network oscillations by rhythmic inhibition. For this purpose, fast-spiking, PV+ interneurons have unique electrophysiological characteristics regarding action potential kinetics and ion conductances, which are associated with high energy expenditure. This is reflected in the neural ultrastructure by enrichment with mitochondria and cytochrome c oxidase, indicating the dependence on oxidative phosphorylation for adenosine-5'-triphosphate (ATP) generation. The high energy expenditure is most likely required for membrane ion transport in dendrites and the extensive axon arbor as well as for presynaptic release of neurotransmitter, gamma-aminobutyric acid (GABA). Fast-spiking, PV+ interneurons are central for the emergence of gamma oscillations (30-100Hz) that provide a fundamental mechanism of complex information processing during sensory perception, motor behavior and memory formation in networks of the hippocampus and the neocortex. Conversely, shortage in glucose and oxygen supply (metabolic stress) and/or excessive formation of reactive oxygen and nitrogen species (oxidative stress) may render these interneurons to be a vulnerable target. Dysfunction in fast-spiking, PV+ interneurons might set a low threshold for impairment of fast network oscillations and thus higher brain functions. This pathophysiological mechanism might be highly relevant for cerebral aging as well as various acute and chronic brain diseases, such as stroke, vascular cognitive impairment, epilepsy, Alzheimer's disease and schizophrenia.
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Affiliation(s)
- Oliver Kann
- Institute of Physiology and Pathophysiology, University of Heidelberg, Heidelberg, Germany; Interdisciplinary Center for Neurosciences (IZN), University of Heidelberg, Heidelberg, Germany.
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Lodge D, Mercier MS. Ketamine and phencyclidine: the good, the bad and the unexpected. Br J Pharmacol 2015; 172:4254-76. [PMID: 26075331 DOI: 10.1111/bph.13222] [Citation(s) in RCA: 123] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 05/29/2015] [Accepted: 06/03/2015] [Indexed: 12/21/2022] Open
Abstract
The history of ketamine and phencyclidine from their development as potential clinical anaesthetics through drugs of abuse and animal models of schizophrenia to potential rapidly acting antidepressants is reviewed. The discovery in 1983 of the NMDA receptor antagonist property of ketamine and phencyclidine was a key step to understanding their pharmacology, including their psychotomimetic effects in man. This review describes the historical context and the course of that discovery and its expansion into other hallucinatory drugs. The relevance of these findings to modern hypotheses of schizophrenia and the implications for drug discovery are reviewed. The findings of the rapidly acting antidepressant effects of ketamine in man are discussed in relation to other glutamatergic mechanisms.
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Affiliation(s)
- D Lodge
- Centre for Synaptic Plasticity, School of Physiology and Pharmacology, University of Bristol, Bristol, UK
| | - M S Mercier
- Centre for Synaptic Plasticity, School of Physiology and Pharmacology, University of Bristol, Bristol, UK
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Tse MT, Piantadosi PT, Floresco SB. Prefrontal cortical gamma-aminobutyric acid transmission and cognitive function: drawing links to schizophrenia from preclinical research. Biol Psychiatry 2015; 77:929-39. [PMID: 25442792 DOI: 10.1016/j.biopsych.2014.09.007] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 08/22/2014] [Accepted: 09/15/2014] [Indexed: 12/28/2022]
Abstract
Cognitive dysfunction in schizophrenia is one of the most pervasive and debilitating aspects of the disorder. Among the numerous neural abnormalities that may contribute to schizophrenia symptoms, perturbations in markers for the inhibitory neurotransmitter gamma-aminobutyric acid (GABA), particularly within the frontal lobes, are some of the most reliable alterations observed at postmortem examination. However, how prefrontal GABA dysfunction contributes to cognitive impairment in schizophrenia remains unclear. We provide an overview of postmortem GABAergic perturbations in the brain affected by schizophrenia and describe circumstantial evidence linking these alterations to cognitive dysfunction. In addition, we conduct a survey of studies using neurodevelopmental, genetic, and pharmacologic rodent models that induce schizophrenia-like cognitive impairments, highlighting the convergence of these mechanistically distinct approaches to prefrontal GABAergic disruption. We review preclinical studies that have directly targeted prefrontal cortical GABAergic transmission using local application of GABAA receptor antagonists. These studies have provided an important link between GABA transmission and cognitive dysfunction in schizophrenia because they show that reducing prefrontal inhibitory transmission induces various cognitive, emotional, and dopaminergic abnormalities that resemble aspects of the disorder. These converging clinical and preclinical findings provide strong support for the idea that perturbations in GABA signaling drive certain forms of cognitive dysfunction in schizophrenia. Future studies using this approach will yield information to refine further a putative "GABA hypothesis" of schizophrenia.
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Affiliation(s)
- Maric T Tse
- Department of Psychology and Brain Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Patrick T Piantadosi
- Department of Psychology and Brain Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Stan B Floresco
- Department of Psychology and Brain Research Centre, University of British Columbia, Vancouver, British Columbia, Canada.
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Long LE, Anderson P, Frank E, Shaw A, Liu S, Huang XF, Pinault D, Karl T, O’Brien TJ, Shannon Weickert C, Jones NC. Neuregulin 1 expression and electrophysiological abnormalities in the Neuregulin 1 transmembrane domain heterozygous mutant mouse. PLoS One 2015; 10:e0124114. [PMID: 25992564 PMCID: PMC4437646 DOI: 10.1371/journal.pone.0124114] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2014] [Accepted: 03/10/2015] [Indexed: 01/29/2023] Open
Abstract
Background The Neuregulin 1 transmembrane domain heterozygous mutant (Nrg1 TM HET) mouse is used to investigate the role of Nrg1 in brain function and schizophrenia-like behavioural phenotypes. However, the molecular alterations in brain Nrg1 expression that underpin the behavioural observations have been assumed, but not directly determined. Here we comprehensively characterise mRNA Nrg1 transcripts throughout development of the Nrg1 TM HET mouse. In addition, we investigate the regulation of high-frequency (gamma) electrophysiological oscillations in this mutant mouse to associate molecular changes in Nrg1 with a schizophrenia-relevant neurophysiological profile. Methods Using exonic probes spanning the cysteine-rich, epidermal growth factor (EGF)-like, transmembrane and intracellular domain encoding regions of Nrg1, mRNA levels were measured using qPCR in hippocampus and frontal cortex from male and female Nrg1 TM HET and wild type-like (WT) mice throughout development. We also performed electrophysiological recordings in adult mice and analysed gamma oscillatory at baseline, in responses to auditory stimuli and to ketamine. Results In both hippocampus and cortex, Nrg1 TM HET mice show significantly reduced expression of the exon encoding the transmembrane domain of Nrg1 compared with WT, but unaltered mRNA expression encoding the extracellular bioactive EGF-like and the cysteine-rich (type III) domains, and development-specific and region-specific reductions in the mRNA encoding the intracellular domain. Hippocampal Nrg1 protein expression was not altered, but NMDA receptor NR2B subunit phosphorylation was lower in Nrg1 TM HET mice. We identified elevated ongoing and reduced sensory-evoked gamma power in Nrg1 TM HET mice. Interpretation We found no evidence to support the claim that the Nrg1 TM HET mouse represents a simple haploinsufficient model. Further research is required to explore the possibility that mutation results in a gain of Nrg1 function.
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Affiliation(s)
- Leonora E. Long
- Schizophrenia Research Institute, Sydney, New South Wales, Australia
- Neuroscience Research Australia, Randwick, New South Wales, Australia
- School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Paul Anderson
- Department of Medicine (Royal Melbourne Hospital), Melbourne Brain Centre, University of Melbourne, Parkville, Victoria, Australia
| | - Elisabeth Frank
- Schizophrenia Research Institute, Sydney, New South Wales, Australia
- University of Wollongong, Wollongong, New South Wales, Australia
| | - Alex Shaw
- Schizophrenia Research Institute, Sydney, New South Wales, Australia
- Neuroscience Research Australia, Randwick, New South Wales, Australia
| | - Shijie Liu
- Department of Medicine (Royal Melbourne Hospital), Melbourne Brain Centre, University of Melbourne, Parkville, Victoria, Australia
| | - Xu-Feng Huang
- Schizophrenia Research Institute, Sydney, New South Wales, Australia
- University of Wollongong, Wollongong, New South Wales, Australia
| | - Didier Pinault
- INSERM U1114, psychopathologie cognitive et physiopathologie de la schizophrénie, Fédération de Médecine Translationnelle de Strasbourg (FMTS), Université de Strasbourg, Strasbourg, France
| | - Tim Karl
- Schizophrenia Research Institute, Sydney, New South Wales, Australia
- Neuroscience Research Australia, Randwick, New South Wales, Australia
- School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Terence J. O’Brien
- Department of Medicine (Royal Melbourne Hospital), Melbourne Brain Centre, University of Melbourne, Parkville, Victoria, Australia
| | - Cynthia Shannon Weickert
- Schizophrenia Research Institute, Sydney, New South Wales, Australia
- Neuroscience Research Australia, Randwick, New South Wales, Australia
- School of Psychiatry, University of New South Wales, Sydney, New South Wales, Australia
- * E-mail: (CSW); (NCJ)
| | - Nigel C. Jones
- Department of Medicine (Royal Melbourne Hospital), Melbourne Brain Centre, University of Melbourne, Parkville, Victoria, Australia
- * E-mail: (CSW); (NCJ)
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Nomura T, Oyamada Y, Fernandes HB, Remmers CL, Xu J, Meltzer HY, Contractor A. Subchronic phencyclidine treatment in adult mice increases GABAergic transmission and LTP threshold in the hippocampus. Neuropharmacology 2015; 100:90-7. [PMID: 25937215 DOI: 10.1016/j.neuropharm.2015.04.012] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 04/16/2015] [Accepted: 04/17/2015] [Indexed: 01/24/2023]
Abstract
Repeated administration of non-competitive N-methyl-d-aspartate (NMDA) receptor antagonists such as phencyclidine (PCP) to rodents causes long-lasting deficits in cognition and memory, and has effects on behaviors that have been suggested to be models of the cognitive impairment associated with schizophrenia (CIAS). Despite this being a widely studied animal model, little is known about the long lasting changes in synapses and circuits that underlie the altered behaviors. Here we examined synaptic transmission ex-vivo in the hippocampus of mice after a subchronic PCP (scPCP) administration regime. We found that after at least one week of drug free washout period when mice have impaired cognitive function, the threshold for long-term potentiation (LTP) of CA1 excitatory synapses was elevated. This elevated LTP threshold was directly related to increased inhibitory input to CA1 pyramidal cells through increased activity of GABAergic neurons. These results suggest repeated PCP administration causes a long-lasting metaplastic change in the inhibitory circuits in the hippocampus that results in impaired LTP, and could contribute to the deficits in hippocampal-dependent memory in PCP-treated mice. Changes in GABA signaling have been described in patients with schizophrenia, therefore our results support using scPCP as a model of CIAS. This article is part of the Special Issue entitled 'Synaptopathy--from Biology to Therapy'.
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Affiliation(s)
- Toshihiro Nomura
- Department of Physiology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Yoshihiro Oyamada
- Department of Psychiatry, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA; Sumitomo Dainippon Pharma Co., Ltd., 33-94 Enoki-cho, Suita, Osaka 564-0053, Japan
| | - Herman B Fernandes
- Department of Physiology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Christine L Remmers
- Department of Physiology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Jian Xu
- Department of Physiology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Herbert Y Meltzer
- Department of Psychiatry, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Anis Contractor
- Department of Physiology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA; Department of Neurobiology, Weinberg College of Arts and Sciences, Northwestern University, Chicago, IL 60611, USA.
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Relationship between somatostatin and death receptor expression in the orbital frontal cortex in schizophrenia: a postmortem brain mRNA study. NPJ SCHIZOPHRENIA 2015; 1:14004. [PMID: 27336026 PMCID: PMC4849439 DOI: 10.1038/npjschz.2014.4] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 10/20/2014] [Accepted: 10/20/2014] [Indexed: 11/09/2022]
Abstract
Background: Recently, we provided evidence showing reductions in GAD67 and Dlx mRNAs in the orbital frontal cortex (OFC) in schizophrenia. It is unknown whether these reductions relate mainly to somatostatin (SST) or parvalbumin (PV) mRNA expression changes, and/or whether these reductions are related to decreased SST mRNA+ interneuron density. Aims: To determine whether inhibitory interneuron deficits in the OFC from people with schizophrenia are greatest for SST or PV mRNAs, and whether any such deficits relate to mRNAs encoding cell death signalling molecules. Methods: Inhibitory interneuron mRNAs (SST; PV: in situ hybridization, quantitative PCR (qPCR)) and death signaling mRNAs [FAS receptor (FASR); TNFSF13: qPCR] were measured in control and schizophrenia subjects (38/38). SST mRNA+ interneuron-like cells were quantified in layer II in the gyrus rectus. Gray matter SST and PV mRNAs were correlated with interstitial white matter neuron (IWMN) density (GAD65/67; NeuN) and death signaling mRNAs. Results: SST mRNA was reduced in OFC layers I–VI in schizophrenia (both in situ and qPCR), with greatest deficit in layer II (67%). Layer II SST mRNA+ neuron density was reduced in schizophrenia (~29%). PV mRNA was reduced in layers III (18%) and IV (31%) with no significant diagnostic difference in PV mRNA measured by qPCR. FASR mRNA was increased in schizophrenia (34%). SST, but not PV, expression correlated negatively with FASR and TNFSF13 expressions and with IWMN density. Conclusions: Our study demonstrates that SST interneurons are predominantly linked to the inhibitory interneuron pathology in the OFC in schizophrenia and that increased death receptor signaling mRNAs relate to prominent laminar deficits in SST mRNA in the OFC in schizophrenia. We suggest that SST interneurons may be more vulnerable to increased death receptor signaling than PV interneurons.
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Elsworth JD, Groman SM, Jentsch JD, Leranth C, Redmond DE, Kim JD, Diano S, Roth RH. Primate phencyclidine model of schizophrenia: sex-specific effects on cognition, brain derived neurotrophic factor, spine synapses, and dopamine turnover in prefrontal cortex. Int J Neuropsychopharmacol 2015; 18:pyu048. [PMID: 25522392 PMCID: PMC4438537 DOI: 10.1093/ijnp/pyu048] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Accepted: 09/15/2014] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Cognitive deficits are a core symptom of schizophrenia, yet they remain particularly resistant to treatment. The model provided by repeatedly exposing adult nonhuman primates to phencyclidine has generated important insights into the neurobiology of these deficits, but it remains possible that administration of this psychotomimetic agent during the pre-adult period, when the dorsolateral prefrontal cortex in human and nonhuman primates is still undergoing significant maturation, may provide a greater understanding of schizophrenia-related cognitive deficits. METHODS The effects of repeated phencyclidine treatment on spine synapse number, dopamine turnover and BDNF expression in dorsolateral prefrontal cortex, and working memory accuracy were examined in pre-adult monkeys. RESULTS One week following phencyclidine treatment, juvenile and adolescent male monkeys demonstrated a greater loss of spine synapses in dorsolateral prefrontal cortex than adult male monkeys. Further studies indicated that in juvenile males, a cognitive deficit existed at 4 weeks following phencyclidine treatment, and this impairment was associated with decreased dopamine turnover, decreased brain derived neurotrophic factor messenger RNA, and a loss of dendritic spine synapses in dorsolateral prefrontal cortex. In contrast, female juvenile monkeys displayed no cognitive deficit at 4 weeks after phencyclidine treatment and no alteration in dopamine turnover or brain derived neurotrophic factor messenger RNA or spine synapse number in dorsolateral prefrontal cortex. In the combined group of male and female juvenile monkeys, significant linear correlations were detected between dopamine turnover, spine synapse number, and cognitive performance. CONCLUSIONS As the incidence of schizophrenia is greater in males than females, these findings support the validity of the juvenile primate phencyclidine model and highlight its potential usefulness in understanding the deficits in dorsolateral prefrontal cortex in schizophrenia and developing novel treatments for the cognitive deficits associated with schizophrenia.
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Affiliation(s)
- John D Elsworth
- Neuropsychopharmacology Research Unit, Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut (Drs Elsworth, Groman, Redmond, and Roth); Department of Psychology and Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, California (Dr Jentsch); Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut (Drs Leranth, Kim, and Diano).
| | - Stephanie M Groman
- Neuropsychopharmacology Research Unit, Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut (Drs Elsworth, Groman, Redmond, and Roth); Department of Psychology and Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, California (Dr Jentsch); Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut (Drs Leranth, Kim, and Diano)
| | - James D Jentsch
- Neuropsychopharmacology Research Unit, Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut (Drs Elsworth, Groman, Redmond, and Roth); Department of Psychology and Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, California (Dr Jentsch); Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut (Drs Leranth, Kim, and Diano)
| | - Csaba Leranth
- Neuropsychopharmacology Research Unit, Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut (Drs Elsworth, Groman, Redmond, and Roth); Department of Psychology and Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, California (Dr Jentsch); Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut (Drs Leranth, Kim, and Diano)
| | - D Eugene Redmond
- Neuropsychopharmacology Research Unit, Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut (Drs Elsworth, Groman, Redmond, and Roth); Department of Psychology and Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, California (Dr Jentsch); Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut (Drs Leranth, Kim, and Diano)
| | - Jung D Kim
- Neuropsychopharmacology Research Unit, Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut (Drs Elsworth, Groman, Redmond, and Roth); Department of Psychology and Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, California (Dr Jentsch); Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut (Drs Leranth, Kim, and Diano)
| | - Sabrina Diano
- Neuropsychopharmacology Research Unit, Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut (Drs Elsworth, Groman, Redmond, and Roth); Department of Psychology and Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, California (Dr Jentsch); Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut (Drs Leranth, Kim, and Diano)
| | - Robert H Roth
- Neuropsychopharmacology Research Unit, Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut (Drs Elsworth, Groman, Redmond, and Roth); Department of Psychology and Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, California (Dr Jentsch); Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut (Drs Leranth, Kim, and Diano)
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Jones KS, Corbin JG, Huntsman MM. Neonatal NMDA receptor blockade disrupts spike timing and glutamatergic synapses in fast spiking interneurons in a NMDA receptor hypofunction model of schizophrenia. PLoS One 2014; 9:e109303. [PMID: 25290690 PMCID: PMC4188593 DOI: 10.1371/journal.pone.0109303] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Accepted: 09/10/2014] [Indexed: 01/06/2023] Open
Abstract
The dysfunction of parvalbumin-positive, fast-spiking interneurons (FSI) is considered a primary contributor to the pathophysiology of schizophrenia (SZ), but deficits in FSI physiology have not been explicitly characterized. We show for the first time, that a widely-employed model of schizophrenia minimizes first spike latency and increases GluN2B-mediated current in neocortical FSIs. The reduction in FSI first-spike latency coincides with reduced expression of the Kv1.1 potassium channel subunit which provides a biophysical explanation for the abnormal spiking behavior. Similarly, the increase in NMDA current coincides with enhanced expression of the GluN2B NMDA receptor subunit, specifically in FSIs. In this study mice were treated with the NMDA receptor antagonist, MK-801, during the first week of life. During adolescence, we detected reduced spike latency and increased GluN2B-mediated NMDA current in FSIs, which suggests transient disruption of NMDA signaling during neonatal development exerts lasting changes in the cellular and synaptic physiology of neocortical FSIs. Overall, we propose these physiological disturbances represent a general impairment to the physiological maturation of FSIs which may contribute to schizophrenia-like behaviors produced by this model.
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Affiliation(s)
- Kevin S. Jones
- Biology Department, Howard University, Washington, DC, United States of America
- Center for Neuroscience Research, Children’s National Medical Center, Washington, DC, United States of America
| | - Joshua G. Corbin
- Center for Neuroscience Research, Children’s National Medical Center, Washington, DC, United States of America
| | - Molly M. Huntsman
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, and Department of Pediatrics, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO, United States of America
- * E-mail:
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Smith KM, Maragnoli ME, Phull PM, Tran KM, Choubey L, Vaccarino FM. Fgfr1 inactivation in the mouse telencephalon results in impaired maturation of interneurons expressing parvalbumin. PLoS One 2014; 9:e103696. [PMID: 25116473 PMCID: PMC4130531 DOI: 10.1371/journal.pone.0103696] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Accepted: 07/04/2014] [Indexed: 11/18/2022] Open
Abstract
Fibroblast growth factors (Fgfs) and their receptors (Fgfr) are expressed in the developing and adult CNS. Previous studies demonstrated a decrease in cortical interneurons and locomotor hyperactivity in mice with a conditional Fgfr1 deletion generated in radial glial cells during midneurogenesis (Fgfr1f/f;hGfapCre+). Here, we report earlier and more extensive inactivation of Fgfr1 in neuroepithelial cells of the CNS (Fgfr1f/f;NesCre+). Similar to findings in Fgfr1f/f;hGfapCre+ mice, parvalbumin positive (PV+) cortical interneurons are also decreased in the neocortex of Fgfr1f/f;NesCre+ mice when compared to control littermates (Fgfr1f/f). Fgfr1f/f;NesCre+ embryos do not differ from controls in the initial specification of GABAergic cells in the ganglionic eminence (GE) as assessed by in situ hybridization for Dlx2, Mash1 and Nkx2. Equal numbers of GABAergic neuron precursors genetically labeled with green fluorescent protein (GFP) were observed at P0 in Fgfr1f/f;hGfapCre+;Gad1-GFP mutant mice. However, fewer GFP+ and GFP+/PV+ interneurons were observed in these mutants at adulthood, indicating that a decrease in cortical interneuron markers is occurring postnatally. Fgfr1 is expressed in cortical astrocytes in the postnatal brain. To test whether the astrocytes of mice lacking Fgfr1 are less capable of supporting interneurons, we co-cultured wild type Gad1-GFP+ interneuron precursors isolated from the medial GE (MGE) with astrocytes from Fgfr1f/f control or Fgfr1f/f;hGfapCre+ mice. Interneurons grown on Fgfr1 deficient astrocytes had small soma size and fewer neurites per cell, but no differences in cell survival. Decreased soma size of Gad67 immunopositive interneurons was also observed in the cortex of adult Fgfr1f/f;NesCre+ mice. Our data indicate that astrocytes from Fgfr1 mutants are impaired in supporting the maturation of cortical GABAergic neurons in the postnatal period. This model may elucidate potential mechanisms of impaired PV interneuron maturation relevant to neuropsychiatric disorders that develop in childhood and adolescence.
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Affiliation(s)
- Karen Müller Smith
- Child Study Center, Yale University, New Haven, Connecticut, United States of America
| | | | - Pooja M. Phull
- Child Study Center, Yale University, New Haven, Connecticut, United States of America
| | - Kathy May Tran
- Child Study Center, Yale University, New Haven, Connecticut, United States of America
| | - Lisha Choubey
- Department of Biology, University of Louisiana at Lafayette, Lafayette, Louisiana, United States of America
| | - Flora M. Vaccarino
- Child Study Center, Yale University, New Haven, Connecticut, United States of America
- Department of Neurobiology, Yale University, New Haven, Connecticut, United States of America
- Kavli Institute for Neuroscience, Yale University, New Haven, Connecticut, United States of America
- * E-mail:
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Highly energized inhibitory interneurons are a central element for information processing in cortical networks. J Cereb Blood Flow Metab 2014; 34:1270-82. [PMID: 24896567 PMCID: PMC4126088 DOI: 10.1038/jcbfm.2014.104] [Citation(s) in RCA: 179] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 05/09/2014] [Accepted: 05/21/2014] [Indexed: 01/09/2023]
Abstract
Gamma oscillations (∼30 to 100 Hz) provide a fundamental mechanism of information processing during sensory perception, motor behavior, and memory formation by coordination of neuronal activity in networks of the hippocampus and neocortex. We review the cellular mechanisms of gamma oscillations about the underlying neuroenergetics, i.e., high oxygen consumption rate and exquisite sensitivity to metabolic stress during hypoxia or poisoning of mitochondrial oxidative phosphorylation. Gamma oscillations emerge from the precise synaptic interactions of excitatory pyramidal cells and inhibitory GABAergic interneurons. In particular, specialized interneurons such as parvalbumin-positive basket cells generate action potentials at high frequency ('fast-spiking') and synchronize the activity of numerous pyramidal cells by rhythmic inhibition ('clockwork'). As prerequisites, fast-spiking interneurons have unique electrophysiological properties and particularly high energy utilization, which is reflected in the ultrastructure by enrichment with mitochondria and cytochrome c oxidase, most likely needed for extensive membrane ion transport and γ-aminobutyric acid metabolism. This supports the hypothesis that highly energized fast-spiking interneurons are a central element for cortical information processing and may be critical for cognitive decline when energy supply becomes limited ('interneuron energy hypothesis'). As a clinical perspective, we discuss the functional consequences of metabolic and oxidative stress in fast-spiking interneurons in aging, ischemia, Alzheimer's disease, and schizophrenia.
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