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Mackenzie SC, Rahmioglu N, Romaniuk L, Collins F, Coxon L, Whalley HC, Vincent K, Zondervan KT, Horne AW, Whitaker LH. Genome-wide association reveals a locus in neuregulin 3 associated with gabapentin efficacy in women with chronic pelvic pain. iScience 2024; 27:110370. [PMID: 39258169 PMCID: PMC11384074 DOI: 10.1016/j.isci.2024.110370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 04/13/2024] [Accepted: 06/21/2024] [Indexed: 09/12/2024] Open
Abstract
Chronic pelvic pain (CPP) in women with no obvious pelvic pathology has few evidence-based treatment options. Our recent multicenter randomized controlled trial (GaPP2) in women with CPP and no obvious pelvic pathology showed that gabapentin did not relieve pain overall and was associated with more side effects than placebo. We conducted an exploratory genome-wide association study using eligible GaPP2 participants aiming to identify genetic variants associated with gabapentin response. One genome-wide significant association with gabapentin analgesic response was identified, rs4442490, an intron variant located in Neuregulin 3 (NRG3) (p = 2·11×10-8; OR = 18·82 (95% CI 4·86-72·83). Analysis of a large sample of UK Biobank participants demonstrated phenome-wide significant brain imaging features of rs4442490, particularly implicating the orbitofrontal cortex. NRG3 is expressed predominantly in central nervous system tissues and plays a critical role in nervous system development, maintenance, and repair, suggesting a neurobiologically plausible role in gabapentin efficacy and potential for personalized analgesic treatment.
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Affiliation(s)
- Scott C. Mackenzie
- Centre for Reproductive Health, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK
| | - Nilufer Rahmioglu
- Wellcome Centre for Human Genetics, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford OX3 7BN, UK
- Oxford Endometriosis CaRe Centre, Nuffield Department of Women’s & Reproductive Health, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Liana Romaniuk
- Division of Psychiatry, University of Edinburgh, Edinburgh EH10 5HF, UK
| | - Frances Collins
- Centre for Reproductive Health, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK
| | - Lydia Coxon
- Oxford Endometriosis CaRe Centre, Nuffield Department of Women’s & Reproductive Health, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Heather C. Whalley
- Division of Psychiatry, University of Edinburgh, Edinburgh EH10 5HF, UK
- Generation Scotland, Institute for Genetics and Cancer, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Katy Vincent
- Oxford Endometriosis CaRe Centre, Nuffield Department of Women’s & Reproductive Health, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Krina T. Zondervan
- Wellcome Centre for Human Genetics, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford OX3 7BN, UK
- Oxford Endometriosis CaRe Centre, Nuffield Department of Women’s & Reproductive Health, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Andrew W. Horne
- Centre for Reproductive Health, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK
| | - Lucy H.R. Whitaker
- Centre for Reproductive Health, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK
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2
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Fisher ML, Prantzalos ER, O'Donovan B, Anderson TL, Sahoo PK, Twiss JL, Ortinski PI, Turner JR. Dynamic effects of ventral hippocampal NRG3/ERBB4 signaling on nicotine withdrawal-induced responses. Neuropharmacology 2024; 247:109846. [PMID: 38211698 PMCID: PMC10923109 DOI: 10.1016/j.neuropharm.2024.109846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 12/18/2023] [Accepted: 01/08/2024] [Indexed: 01/13/2024]
Abstract
Tobacco smoking remains a leading cause of preventable death in the United States, with approximately a 5% success rate for smokers attempting to quit. High relapse rates have been linked to several genetic factors, indicating that the mechanistic relationship between genes and drugs of abuse is a valuable avenue for the development of novel smoking cessation therapies. For example, various single nucleotide polymorphisms (SNPs) in the gene for neuregulin 3 (NRG3) and its cognate receptor, the receptor tyrosine-protein kinase erbB-4 (ERBB4), have been linked to nicotine addiction. Our lab has previously shown that ERBB4 plays a role in anxiety-like behavior during nicotine withdrawal (WD); however, the neuronal mechanisms and circuit-specific effects of NRG3-ERBB4 signaling during nicotine and WD are unknown. The present study utilizes genetic, biochemical, and functional approaches to examine the anxiety-related behavioral and functional role of NRG3-ERBB4 signaling, specifically in the ventral hippocampus (VH) of male and female mice. We report that 24hWD from nicotine is associated with altered synaptic expression of VH NRG3 and ERBB4, and genetic disruption of VH ErbB4 leads to an elimination of anxiety-like behaviors induced during 24hWD. Moreover, we observed attenuation of GABAergic transmission as well as alterations in Ca2+-dependent network activity in the ventral CA1 area of VH ErbB4 knock-down mice during 24hWD. Our findings further highlight contributions of the NRG3-ERBB4 signaling pathway to anxiety-related behaviors seen during nicotine WD.
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Affiliation(s)
- Miranda L Fisher
- Department of Pharmaceutical Sciences, University of Kentucky College of Pharmacy, Lexington, KY, USA
| | - Emily R Prantzalos
- Department of Pharmaceutical Sciences, University of Kentucky College of Pharmacy, Lexington, KY, USA
| | - Bernadette O'Donovan
- Department of Anesthesiology, Duke University School of Medicine, Durham, NC, USA
| | - Tanner L Anderson
- Department of Neuroscience, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Pabitra K Sahoo
- Department of Biological Sciences, University of South Carolina College of Arts and Sciences, Columbia, SC, USA
| | - Jeffery L Twiss
- Department of Biological Sciences, University of South Carolina College of Arts and Sciences, Columbia, SC, USA
| | - Pavel I Ortinski
- Department of Neuroscience, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Jill R Turner
- Department of Pharmaceutical Sciences, University of Kentucky College of Pharmacy, Lexington, KY, USA.
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3
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Boxy P, Nykjær A, Kisiswa L. Building better brains: the pleiotropic function of neurotrophic factors in postnatal cerebellar development. Front Mol Neurosci 2023; 16:1181397. [PMID: 37251644 PMCID: PMC10213292 DOI: 10.3389/fnmol.2023.1181397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 04/26/2023] [Indexed: 05/31/2023] Open
Abstract
The cerebellum is a multifunctional brain region that controls diverse motor and non-motor behaviors. As a result, impairments in the cerebellar architecture and circuitry lead to a vast array of neuropsychiatric and neurodevelopmental disorders. Neurotrophins and neurotrophic growth factors play essential roles in the development as well as maintenance of the central and peripheral nervous system which is crucial for normal brain function. Their timely expression throughout embryonic and postnatal stages is important for promoting growth and survival of both neurons and glial cells. During postnatal development, the cerebellum undergoes changes in its cellular organization, which is regulated by a variety of molecular factors, including neurotrophic factors. Studies have shown that these factors and their receptors promote proper formation of the cerebellar cytoarchitecture as well as maintenance of the cerebellar circuits. In this review, we will summarize what is known on the neurotrophic factors' role in cerebellar postnatal development and how their dysregulation assists in developing various neurological disorders. Understanding the expression patterns and signaling mechanisms of these factors and their receptors is crucial for elucidating their function within the cerebellum and for developing therapeutic strategies for cerebellar-related disorders.
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Affiliation(s)
- Pia Boxy
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
- Danish Research Institute of Translational Neuroscience (DANDRITE)–Nordic EMBL Partnership for Molecular Medicine, Aarhus University, Aarhus, Denmark
- The Danish National Research Foundation Center, PROMEMO, Aarhus University, Aarhus, Denmark
| | - Anders Nykjær
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
- Danish Research Institute of Translational Neuroscience (DANDRITE)–Nordic EMBL Partnership for Molecular Medicine, Aarhus University, Aarhus, Denmark
- The Danish National Research Foundation Center, PROMEMO, Aarhus University, Aarhus, Denmark
| | - Lilian Kisiswa
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
- Danish Research Institute of Translational Neuroscience (DANDRITE)–Nordic EMBL Partnership for Molecular Medicine, Aarhus University, Aarhus, Denmark
- The Danish National Research Foundation Center, PROMEMO, Aarhus University, Aarhus, Denmark
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4
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Fisher ML, Prantzalos ER, O'Donovan B, Anderson T, Sahoo PK, Twiss JL, Ortinski PI, Turner JR. Dynamic Effects of Ventral Hippocampal NRG3/ERBB4 Signaling on Nicotine Withdrawal-Induced Responses. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.17.524432. [PMID: 36711798 PMCID: PMC9882308 DOI: 10.1101/2023.01.17.524432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Tobacco smoking remains a leading cause of preventable death in the United States, with a less than 5% success rate for smokers attempting to quit. High relapse rates have been linked to several genetic factors, indicating that the mechanistic relationship between genes and drugs of abuse is a valuable avenue for the development of novel smoking cessation therapies. For example, various single nucleotide polymorphisms (SNPs) in the gene for neuregulin 3 (NRG3) and its cognate receptor, the receptor tyrosine-protein kinase erbB-4 (ERBB4), have been linked to nicotine addiction. Our lab has previously shown that ERBB4 plays a role in anxiety-like behavior during nicotine withdrawal (WD); however, the neuronal mechanisms and circuit-specific effects of NRG3-ERBB4 signaling during nicotine and WD are unknown. The present study utilizes genetic, biochemical, and functional approaches to examine the anxiety-related behavioral and functional role of NRG3-ERBB4 signaling, specifically in the ventral hippocampus (VH). We report that 24hWD from nicotine is associated with altered synaptic expression of VH NRG3 and ERBB4, and genetic disruption of VH ErbB4 leads to an elimination of anxiety-like behaviors induced during 24hWD. Moreover, we observed attenuation of GABAergic transmission as well as alterations in Ca2+-dependent network activity in the ventral CA1 area of VH ErbB4 knock-down mice during 24hWD. Our findings further highlight contributions of the NRG3-ERBB4 signaling pathway to anxiety-related behaviors seen during nicotine WD.
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Affiliation(s)
- Miranda L Fisher
- Department of Pharmaceutical Sciences, University of Kentucky College of Pharmacy, Lexington, Kentucky, USA
| | - Emily R Prantzalos
- Department of Pharmaceutical Sciences, University of Kentucky College of Pharmacy, Lexington, Kentucky, USA
| | - Bernadette O'Donovan
- Department of Anesthesiology, Duke University School of Medicine, Durham, North Carolina, USA
| | - Tanner Anderson
- Department of Neuroscience, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Pabitra K Sahoo
- Department of Biological Sciences, University of South Carolina College of Arts and Sciences, Columbia, South Carolina, USA
| | - Jeffery L Twiss
- Department of Biological Sciences, University of South Carolina College of Arts and Sciences, Columbia, South Carolina, USA
| | - Pavel I Ortinski
- Department of Neuroscience, University of Kentucky College of Medicine, Lexington, Kentucky, USA
| | - Jill R Turner
- Department of Pharmaceutical Sciences, University of Kentucky College of Pharmacy, Lexington, Kentucky, USA
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5
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Vega-Torres JD, Ontiveros-Angel P, Terrones E, Stuffle EC, Solak S, Tyner E, Oropeza M, dela Peña I, Obenaus A, Ford BD, Figueroa JD. Short-term exposure to an obesogenic diet during adolescence elicits anxiety-related behavior and neuroinflammation: modulatory effects of exogenous neuregulin-1. Transl Psychiatry 2022; 12:83. [PMID: 35220393 PMCID: PMC8882169 DOI: 10.1038/s41398-022-01788-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 12/27/2021] [Accepted: 01/07/2022] [Indexed: 11/21/2022] Open
Abstract
Childhood obesity leads to hippocampal atrophy and altered cognition. However, the molecular mechanisms underlying these impairments are poorly understood. The neurotrophic factor neuregulin-1 (NRG1) and its cognate ErbB4 receptor play critical roles in hippocampal maturation and function. This study aimed to determine whether exogenous NRG1 administration reduces hippocampal abnormalities and neuroinflammation in rats exposed to an obesogenic Western-like diet (WD). Lewis rats were randomly divided into four groups (12 rats/group): (1) control diet+vehicle (CDV); (2) CD + NRG1 (CDN) (daily intraperitoneal injections: 5 μg/kg/day; between postnatal day, PND 21-PND 41); (3) WD + VEH (WDV); (4) WD + NRG1 (WDN). Neurobehavioral assessments were performed at PND 43-49. Brains were harvested for MRI and molecular analyses at PND 49. We found that NRG1 administration reduced hippocampal volume (7%) and attenuated hippocampal-dependent cued fear conditioning in CD rats (56%). NRG1 administration reduced PSD-95 protein expression (30%) and selectively reduced hippocampal cytokine levels (IL-33, GM-CSF, CCL-2, IFN-γ) while significantly impacting microglia morphology (increased span ratio and reduced circularity). WD rats exhibited reduced right hippocampal volume (7%), altered microglia morphology (reduced density and increased lacunarity), and increased levels of cytokines implicated in neuroinflammation (IL-1α, TNF-α, IL-6). Notably, NRG1 synergized with the WD to increase hippocampal ErbB4 phosphorylation and the tumor necrosis alpha converting enzyme (TACE/ADAM17) protein levels. Although the results did not provide sufficient evidence to conclude that exogenous NRG1 administration is beneficial to alleviate obesity-related outcomes in adolescent rats, we identified a potential novel interaction between obesogenic diet exposure and TACE/ADAM17-NRG1-ErbB4 signaling during hippocampal maturation. Our results indicate that supraoptimal ErbB4 activities may contribute to the abnormal hippocampal structure and cognitive vulnerabilities observed in obese individuals.
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Affiliation(s)
- Julio David Vega-Torres
- grid.43582.380000 0000 9852 649XCenter for Health Disparities and Molecular Medicine and Department of Basic Sciences, Physiology Division, Department of Basic Sciences, Loma Linda University Health School of Medicine, Loma Linda, CA USA
| | - Perla Ontiveros-Angel
- grid.43582.380000 0000 9852 649XCenter for Health Disparities and Molecular Medicine and Department of Basic Sciences, Physiology Division, Department of Basic Sciences, Loma Linda University Health School of Medicine, Loma Linda, CA USA
| | - Esmeralda Terrones
- grid.43582.380000 0000 9852 649XCenter for Health Disparities and Molecular Medicine and Department of Basic Sciences, Physiology Division, Department of Basic Sciences, Loma Linda University Health School of Medicine, Loma Linda, CA USA
| | - Erwin C. Stuffle
- grid.43582.380000 0000 9852 649XCenter for Health Disparities and Molecular Medicine and Department of Basic Sciences, Physiology Division, Department of Basic Sciences, Loma Linda University Health School of Medicine, Loma Linda, CA USA
| | - Sara Solak
- grid.43582.380000 0000 9852 649XDepartment of Pharmaceutical and Administrative Sciences, Loma Linda University Health School of Pharmacy, Loma Linda, CA USA
| | - Emma Tyner
- grid.43582.380000 0000 9852 649XDepartment of Pharmaceutical and Administrative Sciences, Loma Linda University Health School of Pharmacy, Loma Linda, CA USA
| | - Marie Oropeza
- grid.43582.380000 0000 9852 649XDepartment of Pharmaceutical and Administrative Sciences, Loma Linda University Health School of Pharmacy, Loma Linda, CA USA
| | - Ike dela Peña
- grid.43582.380000 0000 9852 649XDepartment of Pharmaceutical and Administrative Sciences, Loma Linda University Health School of Pharmacy, Loma Linda, CA USA
| | - Andre Obenaus
- grid.266093.80000 0001 0668 7243Department of Pediatrics, University of California-Irvine, Irvine, CA USA
| | - Byron D. Ford
- grid.266097.c0000 0001 2222 1582Division of Biomedical Sciences, University of California-Riverside School of Medicine, Riverside, CA USA
| | - Johnny D. Figueroa
- grid.43582.380000 0000 9852 649XCenter for Health Disparities and Molecular Medicine and Department of Basic Sciences, Physiology Division, Department of Basic Sciences, Loma Linda University Health School of Medicine, Loma Linda, CA USA
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6
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Kizner V, Naujock M, Fischer S, Jäger S, Reich S, Schlotthauer I, Zuckschwerdt K, Geiger T, Hildebrandt T, Lawless N, Macartney T, Dorner-Ciossek C, Gillardon F. CRISPR/Cas9-mediated Knockout of the Neuropsychiatric Risk Gene KCTD13 Causes Developmental Deficits in Human Cortical Neurons Derived from Induced Pluripotent Stem Cells. Mol Neurobiol 2019; 57:616-634. [PMID: 31402430 DOI: 10.1007/s12035-019-01727-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 07/31/2019] [Indexed: 02/08/2023]
Abstract
The human KCTD13 gene is located within the 16p11.2 locus and copy number variants of this locus are associated with a high risk for neuropsychiatric diseases including autism spectrum disorder and schizophrenia. Studies in zebrafish point to a role of KCTD13 in proliferation of neural precursor cells which may contribute to macrocephaly in 16p11.2 deletion carriers. KCTD13 is highly expressed in the fetal human brain and in mouse cortical neurons, but its contribution to the development and function of mammalian neurons is not completely understood. In the present study, we deleted the KCTD13 gene in human-induced pluripotent stem cells (iPSCs) using CRISPR/Cas9 nickase. Following neural differentiation of KCTD13 deficient and isogenic control iPSC lines, we detected a moderate but significant inhibition of DNA synthesis and proliferation in KCTD13 deficient human neural precursor cells. KCTD13 deficient cortical neurons derived from iPSCs showed decreased neurite formation and reduced spontaneous network activity. RNA-sequencing and pathway analysis pointed to a role for ERBB signaling in these phenotypic changes. Consistently, activating and inhibiting ERBB kinases rescued and aggravated, respectively, impaired neurite formation. In contrast to findings in non-neuronal human HeLa cells, we did not detect an accumulation of the putative KCTD13/Cullin-3 substrate RhoA, and treatment with inhibitors of RhoA signaling did not rescue decreased neurite formation in human KCTD13 knockout neurons. Taken together, our data provide insight into the role of KCTD13 in neurodevelopmental disorders, and point to ERBB signaling as a potential target for neuropsychiatric disorders associated with KCTD13 deficiency.
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Affiliation(s)
- Valeria Kizner
- CNS Diseases Research, Boehringer Ingelheim Pharma GmbH & Co KG, 88397, Biberach an der Riss, Germany
| | - Maximilian Naujock
- CNS Diseases Research, Boehringer Ingelheim Pharma GmbH & Co KG, 88397, Biberach an der Riss, Germany
| | - Sandra Fischer
- CNS Diseases Research, Boehringer Ingelheim Pharma GmbH & Co KG, 88397, Biberach an der Riss, Germany
| | - Stefan Jäger
- CNS Diseases Research, Boehringer Ingelheim Pharma GmbH & Co KG, 88397, Biberach an der Riss, Germany
| | - Selina Reich
- CNS Diseases Research, Boehringer Ingelheim Pharma GmbH & Co KG, 88397, Biberach an der Riss, Germany
| | - Ines Schlotthauer
- CNS Diseases Research, Boehringer Ingelheim Pharma GmbH & Co KG, 88397, Biberach an der Riss, Germany
| | - Kai Zuckschwerdt
- Target Discovery Research, Boehringer Ingelheim Pharma GmbH & Co KG, 88397, Biberach an der Riss, Germany
| | - Tobias Geiger
- Cardio-metabolic Diseases Research, Boehringer Ingelheim Pharma GmbH & Co KG, 88397, Biberach an der Riss, Germany
| | - Tobias Hildebrandt
- Target Discovery Research, Boehringer Ingelheim Pharma GmbH & Co KG, 88397, Biberach an der Riss, Germany
| | - Nathan Lawless
- Target Discovery Research, Boehringer Ingelheim Pharma GmbH & Co KG, 88397, Biberach an der Riss, Germany
| | - Thomas Macartney
- MRC Protein Phosphorylation and Ubiquitylation Unit, Sir James Black Centre, University of Dundee, Dundee, DD1 5EH, UK
| | - Cornelia Dorner-Ciossek
- CNS Diseases Research, Boehringer Ingelheim Pharma GmbH & Co KG, 88397, Biberach an der Riss, Germany
| | - Frank Gillardon
- CNS Diseases Research, Boehringer Ingelheim Pharma GmbH & Co KG, 88397, Biberach an der Riss, Germany.
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Yamazaki Y, Sumikawa K. Nicotine-induced neuroplasticity counteracts the effect of schizophrenia-linked neuregulin 1 signaling on NMDAR function in the rat hippocampus. Neuropharmacology 2016; 113:386-395. [PMID: 27784625 DOI: 10.1016/j.neuropharm.2016.10.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 10/10/2016] [Accepted: 10/21/2016] [Indexed: 12/13/2022]
Abstract
A high rate of heavy tobacco smoking among people with schizophrenia has been suggested to reflect self-medication and amelioration of cognitive dysfunction, a core feature of schizophrenia. NMDAR hypofunction is hypothesized to be a mechanism of cognitive dysfunction, and excessive schizophrenia-linked neuregulin 1 (NRG1) signaling through its receptor ErbB4 can suppress NMDAR function by preventing Src-mediated enhancement of NMDAR responses. Here we investigated whether chronic nicotine exposure in rats by subcutaneous injection of nicotine (0.5-1 mg/kg, twice daily for 10-15 days) counteracts the suppressive effect of NRG1β on NMDAR-mediated responses recorded from CA1 pyramidal cells in acute hippocampal slices. We found that NRG1β, which prevents the enhancement of NMDAR responses by the Src-family-kinase-activating peptide pYEEI in naive rats, failed to block the effect of pYEEI in nicotine-exposed rats. In naive rats, NRG1β acts only on GluN2B-NMDARs by blocking their Src-mediated upregulation. Chronic nicotine exposure causes enhanced GluN2B-NMDAR responses via Src upregulation and recruits Fyn for the enhancement of GluN2A-NMDAR responses. NRG1β has no effect on both enhanced basal GluN2B-NMDAR responses and Fyn-mediated enhancement of GluN2A-NMDAR responses. Src-mediated enhancement of GluN2B-NMDAR responses and Fyn-mediated enhancement of GluN2A-NMDAR responses initiate long-term potentiation (LTP) of AMPAR synaptic responses in naive and nicotine-exposed CA1 pyramidal cells, respectively. These results suggest that NRG1β suppresses LTP by blocking Src-mediated enhancement of GluN2B-NMDAR responses, but has no effect on LTP in nicotine-exposed rats. These effects of chronic nicotine exposure may counteract the negative effect of increased NRG1-ErbB4 signaling on the cellular mechanisms of learning and memory in individuals with schizophrenia, and therefore may motivate heavy smoking.
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Affiliation(s)
- Yoshihiko Yamazaki
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697-4550, USA; Department of Neurophysiology, Yamagata University School of Medicine, Yamagata 990-9585, Japan
| | - Katumi Sumikawa
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697-4550, USA.
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8
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Li Y, Liu G, Li H, Bi Y. Neuregulin-1β Regulates the migration of Different Neurochemical Phenotypic Neurons from Organotypically Cultured Dorsal Root Ganglion Explants. Cell Mol Neurobiol 2016; 36:69-81. [PMID: 26093851 PMCID: PMC11482311 DOI: 10.1007/s10571-015-0221-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 06/02/2015] [Indexed: 10/24/2022]
Abstract
Neuregulin-1β (NRG-1β) has multiple roles in the development and function in the nervous system and exhibits potent neuroprotective properties. In the present study, organotypically cultured dorsal root ganglion (DRG) explants were used to evaluate the effects of NRG-1β on migration of two major phenotypic classes of DRG neurons. The signaling pathways involved in these effects were also determined. Organotypically cultured DRG explants were exposed to NRG-1β (20 nmol/L), the phosphatidylinositol 3-kinase inhibitor LY294002 (10 μmol/L) plus NRG-1β (20 nmol/L), the extracellular signal-regulated protein kinase (ERK1/2) inhibitor PD98059 (10 μmol/L) plus NRG-1β (20 nmol/L), and LY294002 (10 μmol/L) plus PD98059 (10 μmol/L) plus NRG-1β (20 nmol/L), respectively, for 3 days. The DRG explants were continuously exposed to culture media as a control. After that, all above cultures were processed for detecting the mRNA levels of calcitonin gene-related peptide (CGRP) and neurofilament-200 (NF-200) by real-time PCR analysis. CGRP and NF-200 expression in situ was determined by fluorescent labeling technique. The results showed that NRG-1β elevated the mRNA and protein levels of CGRP and NF-200. NRG-1β also increased the number and the percentage of CGRP-immunoreactive (IR) migrating neurons and NF-200-IR migrating neurons. Inhibitors (LY294002, PD98059) either alone or in combination blocked the effects of NRG-1β. The contribution of NRG-1β on modulating distinct neurochemical phenotypic plasticity of DRG neurons suggested that NRG-1β signaling system might play an important role on the biological effects of primary sensory neurons.
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Affiliation(s)
- Yunfeng Li
- Department of Cardiosurgery, Shandong University Qilu Hospital, 107 West Wenhua Xi Road, Jinan, 250012, Shandong Province, China.
| | - Guixiang Liu
- Department of Histology and Embryology, Binzhou Medical College, Binzhou, 256603, China.
| | - Hao Li
- Department of Orthopaedics, Shandong University Qilu Hospital, Jinan, 250012, China.
| | - Yanwen Bi
- Department of Cardiosurgery, Shandong University Qilu Hospital, 107 West Wenhua Xi Road, Jinan, 250012, Shandong Province, China.
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Interneuronal DISC1 regulates NRG1-ErbB4 signalling and excitatory-inhibitory synapse formation in the mature cortex. Nat Commun 2015; 6:10118. [PMID: 26656849 PMCID: PMC4682104 DOI: 10.1038/ncomms10118] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2015] [Accepted: 11/05/2015] [Indexed: 12/11/2022] Open
Abstract
Neuregulin-1 (NRG1) and its receptor ErbB4 influence several processes of neurodevelopment, but the mechanisms regulating this signalling in the mature brain are not well known. DISC1 is a multifunctional scaffold protein that mediates many cellular processes. Here we present a functional relationship between DISC1 and NRG1-ErbB4 signalling in mature cortical interneurons. By cell type-specific gene modulation in vitro and in vivo including in a mutant DISC1 mouse model, we demonstrate that DISC1 inhibits NRG1-induced ErbB4 activation and signalling. This effect is likely mediated by competitive inhibition of binding of ErbB4 to PSD95. Finally, we show that interneuronal DISC1 affects NRG1-ErbB4-mediated phenotypes in the fast spiking interneuron-pyramidal neuron circuit. Post-mortem brain analyses and some genetic studies have reported interneuronal deficits and involvement of the DISC1, NRG1 and ErbB4 genes in schizophrenia, respectively. Our results suggest a mechanism by which cross-talk between DISC1 and NRG1-ErbB4 signalling may contribute to these deficits. Neuregulin-1 and DISC1 signalling pathways have both been linked to neurodevelopment and schizophrenia. Here, Seshadri et al. demonstrate that DISC1 negatively regulates NRG1-induced ErbB4 signalling in adult cortical interneurons both in vitro and in vivo, possibly via competitive binding to PSD95.
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10
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Chohan TW, Nguyen A, Todd SM, Bennett MR, Callaghan P, Arnold JC. Partial genetic deletion of neuregulin 1 and adolescent stress interact to alter NMDA receptor binding in the medial prefrontal cortex. Front Behav Neurosci 2014; 8:298. [PMID: 25324742 PMCID: PMC4179617 DOI: 10.3389/fnbeh.2014.00298] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2014] [Accepted: 08/13/2014] [Indexed: 02/02/2023] Open
Abstract
Schizophrenia is thought to arise due to a complex interaction between genetic and environmental factors during early neurodevelopment. We have recently shown that partial genetic deletion of the schizophrenia susceptibility gene neuregulin 1 (Nrg1) and adolescent stress interact to disturb sensorimotor gating, neuroendocrine activity and dendritic morphology in mice. Both stress and Nrg1 may have converging effects upon N-methyl-D-aspartate receptors (NMDARs) which are implicated in the pathogenesis of schizophrenia, sensorimotor gating and dendritic spine plasticity. Using an identical repeated restraint stress paradigm to our previous study, here we determined NMDAR binding across various brain regions in adolescent Nrg1 heterozygous (HET) and wild-type (WT) mice using [3H] MK-801 autoradiography. Repeated restraint stress increased NMDAR binding in the ventral part of the lateral septum (LSV) and the dentate gyrus (DG) of the hippocampus irrespective of genotype. Partial genetic deletion of Nrg1 interacted with adolescent stress to promote an altered pattern of NMDAR binding in the infralimbic (IL) subregion of the medial prefrontal cortex. In the IL, whilst stress tended to increase NMDAR binding in WT mice, it decreased binding in Nrg1 HET mice. However, in the DG, stress selectively increased the expression of NMDAR binding in Nrg1 HET mice but not WT mice. These results demonstrate a Nrg1-stress interaction during adolescence on NMDAR binding in the medial prefrontal cortex.
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Affiliation(s)
- Tariq W Chohan
- The Brain and Mind Research Institute, University of Sydney Sydney, NSW, Australia ; Discipline of Pharmacology, School of Medical Science, University of Sydney Sydney, NSW, Australia
| | - An Nguyen
- The Brain and Mind Research Institute, University of Sydney Sydney, NSW, Australia ; ANSTO LifeSciences, Australian Nuclear Science and Technology Organisation Sydney, NSW, Australia
| | - Stephanie M Todd
- The Brain and Mind Research Institute, University of Sydney Sydney, NSW, Australia ; Discipline of Pharmacology, School of Medical Science, University of Sydney Sydney, NSW, Australia
| | - Maxwell R Bennett
- The Brain and Mind Research Institute, University of Sydney Sydney, NSW, Australia
| | - Paul Callaghan
- The Brain and Mind Research Institute, University of Sydney Sydney, NSW, Australia ; ANSTO LifeSciences, Australian Nuclear Science and Technology Organisation Sydney, NSW, Australia
| | - Jonathon C Arnold
- The Brain and Mind Research Institute, University of Sydney Sydney, NSW, Australia ; Discipline of Pharmacology, School of Medical Science, University of Sydney Sydney, NSW, Australia
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11
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Mei L, Nave KA. Neuregulin-ERBB signaling in the nervous system and neuropsychiatric diseases. Neuron 2014; 83:27-49. [PMID: 24991953 DOI: 10.1016/j.neuron.2014.06.007] [Citation(s) in RCA: 436] [Impact Index Per Article: 39.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Neuregulins (NRGs) comprise a large family of growth factors that stimulate ERBB receptor tyrosine kinases. NRGs and their receptors, ERBBs, have been identified as susceptibility genes for diseases such as schizophrenia (SZ) and bipolar disorder. Recent studies have revealed complex Nrg/Erbb signaling networks that regulate the assembly of neural circuitry, myelination, neurotransmission, and synaptic plasticity. Evidence indicates there is an optimal level of NRG/ERBB signaling in the brain and deviation from it impairs brain functions. NRGs/ERBBs and downstream signaling pathways may provide therapeutic targets for specific neuropsychiatric symptoms.
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Affiliation(s)
- Lin Mei
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912, USA; Department of Neurology, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912, USA; Charlie Norwood VA Medical Center, Augusta, GA 30904, USA.
| | - Klaus-Armin Nave
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, 37075 Goettingen, Germany.
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12
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Yue W, Song L, Fu G, Li Y, Liu H. Neuregulin-1β regulates tyrosine kinase receptor expression in cultured dorsal root ganglion neurons with excitotoxicity induced by glutamate. ACTA ACUST UNITED AC 2012; 180:33-42. [PMID: 23142316 DOI: 10.1016/j.regpep.2012.10.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2012] [Revised: 09/08/2012] [Accepted: 10/17/2012] [Indexed: 01/14/2023]
Abstract
Neuregulin-1 (NRG-1) signaling regulates neuronal development, migration, myelination, and synaptic maintenance. Three members of tyrosine kinase receptor (Trk) family, TrkA, TrkB, and TrkC, have been identified in DRG neurons. Whether NRG-1β and its signaling pathways influence the expression of these Trk receptors in DRG neurons is still unclear. In the present study, primary cultured DRG neurons were used to determine the effects of NRG-1β on TrkA, TrkB, and TrkC expression in DRG neurons with excitotoxicity induced by glutamate (Glu). The involvement of phosphatidylinositol 3-kinase (PI3K)/Akt and the effects of extracellular signal-regulated protein kinase (ERK1/2) signaling pathways on NRG-1β were also determined. DRG neurons were cultured for 48h and then exposed to Glu, Glu plus NRG-1β, LY294002 plus Glu plus NRG-1β, PD98059 plus Glu plus NRG-1β, and PD98059 plus LY294002 plus Glu plus NRG-1β for an additional 24h. The DRG neurons were continuously exposed to culture media as a control. After that, all cultures were processed for detection of mRNA levels of TrkA, TrkB, and TrkC using real time-PCR analysis. Protein levels of TrkA, TrkB, and TrkC were detected using a Western blot assay. The expression of TrkA, TrkB, and TrkC in situ was determined by a fluorescent labeling technique. The levels of phosphorylated Akt (pAkt), phosphorylated ERK1/2 (pERK1/2), total protein levels of Akt and ERK1/2 were detected using a Western blot assay. The results indicated that in primary cultured DRG neurons with excitotoxicity induced by Glu, NRG-1β increased the expression of TrkA and TrkB their mRNAs, but not TrkC and its mRNA. Inhibitors (LY294002, PD98059) either alone or in combination blocked the effects of NRG-1β. NRG-1β may play an important role in regulating the expression of different Trk receptors in DRG neurons through the PI3K/Akt and ERK1/2 signaling pathways.
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Affiliation(s)
- Weiming Yue
- Department of Thoracic Surgery, Shandong University Qilu Hospital, Jinan 250012, China.
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13
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Fenster C, Vullhorst D, Buonanno A. Acute neuregulin-1 signaling influences AMPA receptor mediated responses in cultured cerebellar granule neurons. Brain Res Bull 2012; 87:21-9. [PMID: 22044943 PMCID: PMC3432401 DOI: 10.1016/j.brainresbull.2011.10.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Revised: 09/29/2011] [Accepted: 10/20/2011] [Indexed: 12/31/2022]
Abstract
Neuregulin-1 (NRG1) is a trophic and differentiation factor that signals through ErbB receptor tyrosine kinases to regulate nervous system development. Previous studies have demonstrated that NRG1 affects plasticity at glutamatergic synapses in principal glutamatergic neurons of the hippocampus and frontal cortex; however, immunohistochemical and genetic analyses strongly suggest these effects are indirect and mediated via ErbB4 receptors on GABAergic interneurons. Here, we used cultured cerebellar granule cells (CGCs) that express ErbB4 to analyze the cell-autonomous effects of NRG1 stimulation on glutamatergic function. These cultures have the advantage that they are relatively homogenous and consist primarily of granule neurons that express ErbB4. We show that acute NRG1 treatment does not affect whole-cell AMPA or NMDA receptor (NMDAR) mediated currents in CGCs at 10-12 days in vitro. NRG1 also does not affect the frequency or amplitude of spontaneous AMPAR or NMDAR mediated miniature excitatory post-synaptic currents (mEPSCs). To further investigate the effects of NRG1 on activity-dependent plasticity of glutamatergic synapses in CGCs, we characterized the effects of high-glyine/0 Mg(2+) (which activates synaptic NMDARs) on AMPAR-mEPSC frequency and amplitude. We show that high-glycine induces a form of chemical long-term potentiation (chemLTP) in CGCs characterized by an increase in AMPAR-mEPSC frequency but not amplitude. Moreover, NRG1 induces a decrease in AMPAR-mEPSC frequency following chemLTP, but does not affect AMPAR-mEPSC amplitude. CGCs in our cultures conditions express low levels of GluR1, in contrast to dissociated hippocampal cultures, but do express the long isoform of GluR4. This study provides first evidence that (1) high-glycine can induce plasticity at glutamatergic synapses in CGCs, and (2) that acute NRG1/ErbB-signaling can regulate glutamatergic plasticity in CGCs. Taken together with previous reports, our results suggest that, similar to Schaeffer collateral to CA1 synapses, NRG1 effects are activity dependent and mediated via modulation of synaptic AMPARs.
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Affiliation(s)
- Catherine Fenster
- Department of Biology/Toxicology, 401 College Avenue, Ashland University, Ashland, OH 44805
- Section of Developmental Neurobiology, NICHD, Porter Neuroscience Research Center, Building 35, Room 2C-1002, 35 Convent Drive, Bethesda, MD 20892. 35 Convent Dr Room 2C1000, MSC 3713 Bethesda Md 20892-3713
| | - Detlef Vullhorst
- Section of Developmental Neurobiology, NICHD, Porter Neuroscience Research Center, Building 35, Room 2C-1002, 35 Convent Drive, Bethesda, MD 20892. 35 Convent Dr Room 2C1000, MSC 3713 Bethesda Md 20892-3713
| | - Andres Buonanno
- Section of Developmental Neurobiology, NICHD, Porter Neuroscience Research Center, Building 35, Room 2C-1000, 35 Convent Drive, Bethesda, MD 20892
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Bennett M. Schizophrenia: susceptibility genes, dendritic-spine pathology and gray matter loss. Prog Neurobiol 2011; 95:275-300. [DOI: 10.1016/j.pneurobio.2011.08.003] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Revised: 08/12/2011] [Accepted: 08/15/2011] [Indexed: 02/01/2023]
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15
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Liu Z, Gao W, Wang Y, Zhang W, Liu H, Li Z. Neuregulin-1β regulates outgrowth of neurites and migration of neurofilament 200 neurons from dorsal root ganglial explants in vitro. Peptides 2011; 32:1244-8. [PMID: 21515322 DOI: 10.1016/j.peptides.2011.04.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2011] [Revised: 04/04/2011] [Accepted: 04/07/2011] [Indexed: 01/05/2023]
Abstract
Neuregulin-1β (NRG-1β) signaling has multiple functions in neurons. To assess NRG-1β on neurite outgrowth and neuronal migration in vitro, organotypic dorsal root ganglion (DRG) neuronal culture model was established. Neurite outgrowth and neuronal migration were evaluated using this culture model in the presence (5nmol/L, 10nmol/L, 20nmol/L) or absence of NRG-1β. Neurofilament 200 (NF-200)-immunoreactive (IR) neurons were determined as the migrating neurons. The number of nerve fiber bundles extended from DRG explant increased significantly in the presence of NRG-1β (5nmol/L, 23.0±2.2, P<0.05; 10nmol/L, 27.0±2.7, P<0.001; 20nmol/L, 30.8±3.7, P<0.001) as compared with that in the absence of NRG-1β (19.0±2.2). The number of neurons migrating from DRG explants increased significantly in the presence of NRG-1β (5nmol/L, 39.6±5.0, P<0.05; 10nmol/L, 54.6±6.7, P<0.001; 20nmol/L, 62.2±5.7, P<0.001) as compared with that in the absence of NRG-1β (31.6±4.0). Moreover, the increase of the number of nerve fiber bundles and the number of migrating NF-200-IR neurons was dose-dependent for NRG-1β addition. The data in this study imply that NRG-1β promotes neurite outgrowth and neuronal migration from DRG explants in vitro.
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Affiliation(s)
- Zhen Liu
- Department of Anatomy, Shandong University School of Medicine, 44 Wenhua Xi Road, Jinan, Shandong Province 250012, China
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16
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Regulation of cell cycle and DNA repair in post-mitotic GABA neurons in psychotic disorders. Neuropharmacology 2010; 60:1232-42. [PMID: 21184762 DOI: 10.1016/j.neuropharm.2010.12.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2010] [Revised: 11/24/2010] [Accepted: 12/15/2010] [Indexed: 11/24/2022]
Abstract
Disturbances of cell cycle regulation and DNA repair in post-mitotic neurons have been implicated in degenerative and malignant diseases of the human brain. Recent work is now suggesting that abnormal regulation of these functions in GABA cells of the adult hippocampus may also play a role in two neuropsychiatric disorders. In schizophrenia and bipolar disorder, a network of genes involved in the regulation of GAD₆₇, a marker for the functional differentiation of GABA cells, show pronounced changes in expression and include kainate receptor subunits, TGFβ and Wnt signaling pathways, epigenetic factors and transcription factors. One of these genes, cyclin D2, is involved in the regulation of cell cycle and DNA repair and appears to be a pivotal element in linking GAD₆₇ expression with these functional clusters of genes. Dysfunction of post-mitotic GABAergic neurons in the adult hippocampus of patients with psychotic disorders is associated with changes in the expression of genes that are involved in the maintenance of functional and genomic integrity of GABA cells. The nature of these changes is quite different in schizophrenia and bipolar disorder, suggesting that a common cell phenotype (in this case, decreased GAD₆₇ expression) may involve two fundamentally different molecular endophenotypes and reflect unique susceptibility genes involved in the respective disorders. This article is part of a Special Issue entitled 'Trends in neuropharmacology: in memory of Erminio Costa'.
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Bennett M. Positive and negative symptoms in schizophrenia: the NMDA receptor hypofunction hypothesis, neuregulin/ErbB4 and synapse regression. Aust N Z J Psychiatry 2009; 43:711-21. [PMID: 19629792 DOI: 10.1080/00048670903001943] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Carlsson has put forward the hypothesis that the positive and negative symptoms of schizophrenia are due to failure of mesolimbic and mesocortical projections consequent on hypofunction of the glutamate N-methyl-d-aspartate (NMDA) receptor. The hypothesis has been recently emphasized in this Journal that the loss of synaptic spines with NMDA receptors, which can be precipitated by stress, can explain the emergence of positive symptoms such as hallucinations and that this synapse regression involves molecules such as neuregulin and its receptor ErbB4 that have been implicated in schizophrenia. In this essay these two hypotheses are brought together in a single scheme in which emphasis is placed on the molecular pathways from neuregulin/ErbB4, to modulation of the NMDA receptors, subsequent changes in the synaptic spine's cytoskeletal apparatus and so regression of the spines. It is suggested that identification of the molecular constituents of this pathway will allow synthesis of suitable substances for removing the hypofunction of NMDA receptors and so the phenotypic consequences that flow from this hypofunction.
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Affiliation(s)
- Maxwell Bennett
- Brain and Mind Research Institute, University of Sydney, NSW, Australia.
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18
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Site-specific regulation of cell cycle and DNA repair in post-mitotic GABA cells in schizophrenic versus bipolars. Proc Natl Acad Sci U S A 2009; 106:11731-6. [PMID: 19564623 DOI: 10.1073/pnas.0903066106] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
GABA cell dysfunction in both schizophrenia (SZ) and bipolar disorder (BD) involves decreased GAD(67) expression, although this change involves fundamentally different networks of genes in the 2 disorders. One gene that is common to these 2 networks is cyclin D2, a key component of cell cycle regulation that shows increased expression in SZ, but decreased expression in BD. Because of the importance of cell cycle regulation in maintaining functional differentiation and DNA repair, the current study has examined the genes involved in the G(1) and G(2) checkpoints to generate new hypotheses regarding the regulation of the GABA cell phenotype in the hippocampus of SZ and BD. The results have demonstrated significant changes in cell cycle regulation in both SZ and BD and these changes include the transcriptional complex (TC) that controls the expression of E2F/DP-1 target genes critical for progression to G(2)/M. The methyl-CpG binding domain protein (MBD4) that is pivotal for DNA repair, is significantly up-regulated in the stratum oriens (SO) of CA3/2 and CA1 in SZs and BDs. However, other genes associated with the TC, and the G(1) and G(2) checkpoints, show complex changes in expression in the SO of CA3/2 and CA1 of both SZs and BDS. Overall, the patterns of expression observed have suggested that the regulation of functional differentiation and/or genomic integrity of hippocampal GABA cells varies according to diagnosis and their location within the trisynaptic pathway.
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