1
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Piergiorge RM, da Silva Francisco Junior R, de Vasconcelos ATR, Santos-Rebouças CB. Multi-layered transcriptomic analysis reveals a pivotal role of FMR1 and other developmental genes in Alzheimer's disease-associated brain ceRNA network. Comput Biol Med 2023; 166:107494. [PMID: 37769462 DOI: 10.1016/j.compbiomed.2023.107494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 09/05/2023] [Accepted: 09/15/2023] [Indexed: 09/30/2023]
Abstract
Alzheimer's disease (AD) is an increasingly neurodegenerative disorder that causes progressive cognitive decline and memory impairment. Despite extensive research, the underlying causes of late-onset AD (LOAD) are still in progress. This study aimed to establish a network of competing regulatory interactions involving circular RNAs (circRNAs), microRNAs (miRNAs), RNA-binding proteins (RBPs), and messenger RNAs (mRNAs) connected to LOAD. A systematic analysis of publicly available expression data was conducted to identify integrated differentially expressed genes (DEGs) from the hippocampus of LOAD patients. Subsequently, gene co-expression analysis identified modules comprising highly expressed DEGs that act cooperatively. The competition between co-expressed DEGs and miRNAs/RBPs and the simultaneous interactions between circRNA and miRNA/RBP revealed a complex ceRNA network responsible for post-transcriptional regulation in LOAD. Hippocampal expression data for miRNAs, circRNAs, and RBPs were used to filter relevant relationships for AD. An integrated topological score was used to identify the highly connected hub gene, from which a brain core ceRNA subnetwork was generated. The Fragile X Messenger Ribonucleoprotein 1 (FMR1) coding for the RBP FMRP emerged as the prominent driver gene in this subnetwork. FMRP has been previously related to AD but not in a ceRNA network context. Also, the substantial number of neurodevelopmental genes in the ceRNA subnetwork and their related biological pathways strengthen that AD shares common pathological mechanisms with developmental conditions. Our results enhance the current knowledge about the convergent ceRNA regulatory pathways underlying AD and provide potential targets for identifying early biomarkers and developing novel therapeutic interventions.
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Affiliation(s)
- Rafael Mina Piergiorge
- Department of Genetics, Institute of Biology Roberto Alcantara Gomes, State University of Rio de Janeiro, Rio de Janeiro, Brazil
| | | | | | - Cíntia Barros Santos-Rebouças
- Department of Genetics, Institute of Biology Roberto Alcantara Gomes, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
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2
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Westmark CJ. Toward an understanding of the role of the exposome on fragile X phenotypes. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2023; 173:141-170. [PMID: 37993176 DOI: 10.1016/bs.irn.2023.08.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2023]
Abstract
Fragile X syndrome (FXS) is the leading known monogenetic cause of autism with an estimated 21-50% of FXS individuals meeting autism diagnostic criteria. A critical gap in medical care for persons with autism is an understanding of how environmental exposures and gene-environment interactions affect disease outcomes. Our research indicates more severe neurological and metabolic outcomes (seizures, autism, increased body weight) in mouse and human models of autism spectrum disorders (ASD) as a function of diet. Thus, early-life exposure to chemicals in the diet could cause or exacerbate disease outcomes. Herein, we review the effects of potential dietary toxins, i.e., soy phytoestrogens, glyphosate, and polychlorinated biphenyls (PCB) in FXS and other autism models. The rationale is that potentially toxic chemicals in the diet, particularly infant formula, could contribute to the development and/or severity of ASD and that further study in this area has potential to improve ASD outcomes through dietary modification.
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Affiliation(s)
- Cara J Westmark
- Department of Neurology, University of Wisconsin-Madison, Medical Sciences Center, Room 3619, 1300 University Avenue, Madison, WI, United States; Molecular Environmental Toxicology Center, University of Wisconsin-Madison, Medical Sciences Center, Room 3619, 1300 University Avenue, Madison, WI, United States.
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3
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Song C, Broadie K. Fragile X mental retardation protein coordinates neuron-to-glia communication for clearance of developmentally transient brain neurons. Proc Natl Acad Sci U S A 2023; 120:e2216887120. [PMID: 36920921 PMCID: PMC10041173 DOI: 10.1073/pnas.2216887120] [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: 10/05/2022] [Accepted: 02/07/2023] [Indexed: 03/16/2023] Open
Abstract
In the developmental remodeling of brain circuits, neurons are removed by glial phagocytosis to optimize adult behavior. Fragile X mental retardation protein (FMRP) regulates neuron-to-glia signaling to drive glial phagocytosis for targeted neuron pruning. We find that FMRP acts in a mothers against decapentaplegic (Mad)-insulin receptor (InR)-protein kinase B (Akt) pathway to regulate pretaporter (Prtp) and amyloid precursor protein-like (APPL) signals directing this glial clearance. Neuronal RNAi of Drosophila fragile X mental retardation 1 (dfmr1) elevates mad transcript levels and increases pMad signaling. Neuronal dfmr1 and mad RNAi both elevate phospho-protein kinase B (pAkt) and delay neuron removal but cause opposite effects on InR expression. Genetically correcting pAkt levels in the mad RNAi background restores normal remodeling. Consistently, neuronal dfmr1 and mad RNAi both decrease Prtp levels, whereas neuronal InR and akt RNAi increase Prtp levels, indicating FMRP works with pMad and insulin signaling to tightly regulate Prtp signaling and thus control glial phagocytosis for correct circuit remodeling. Neuronal dfmr1 and mad and akt RNAi all decrease APPL levels, with the pathway signaling higher glial endolysosome activity for phagocytosis. These findings reveal a FMRP-dependent control pathway for neuron-to-glia communication in neuronal pruning, identifying potential molecular mechanisms for devising fragile X syndrome treatments.
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Affiliation(s)
- Chunzhu Song
- Department of Biological Sciences, Vanderbilt University and Medical Center, Nashville, TN37235
| | - Kendal Broadie
- Department of Biological Sciences, Vanderbilt University and Medical Center, Nashville, TN37235
- Department of Cell and Developmental Biology, Vanderbilt University and Medical Center, Nashville, TN37235
- Kennedy Center for Research on Human Development, Vanderbilt University and Medical Center, Nashville, TN37235
- Vanderbilt Brain Institute, Vanderbilt University and Medical Center, Nashville, TN37235
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4
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Cencelli G, Pacini L, De Luca A, Messia I, Gentile A, Kang Y, Nobile V, Tabolacci E, Jin P, Farace MG, Bagni C. Age-Dependent Dysregulation of APP in Neuronal and Skin Cells from Fragile X Individuals. Cells 2023; 12:758. [PMID: 36899894 PMCID: PMC10000963 DOI: 10.3390/cells12050758] [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: 11/06/2022] [Revised: 01/02/2023] [Accepted: 01/06/2023] [Indexed: 03/04/2023] Open
Abstract
Fragile X syndrome (FXS) is the most common form of monogenic intellectual disability and autism, caused by the absence of the functional fragile X messenger ribonucleoprotein 1 (FMRP). FXS features include increased and dysregulated protein synthesis, observed in both murine and human cells. Altered processing of the amyloid precursor protein (APP), consisting of an excess of soluble APPα (sAPPα), may contribute to this molecular phenotype in mice and human fibroblasts. Here we show an age-dependent dysregulation of APP processing in fibroblasts from FXS individuals, human neural precursor cells derived from induced pluripotent stem cells (iPSCs), and forebrain organoids. Moreover, FXS fibroblasts treated with a cell-permeable peptide that decreases the generation of sAPPα show restored levels of protein synthesis. Our findings suggest the possibility of using cell-based permeable peptides as a future therapeutic approach for FXS during a defined developmental window.
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Affiliation(s)
- Giulia Cencelli
- Department of Biomedicine and Prevention, Faculty of Medicine, University of Rome Tor Vergata, 00133 Rome, Italy
- Institute of Neurosurgery, Fondazione Policlinico Universitario A. Gemelli Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Catholic University, 00168 Rome, Italy
| | - Laura Pacini
- Department of Biomedicine and Prevention, Faculty of Medicine, University of Rome Tor Vergata, 00133 Rome, Italy
- Faculty of Medicine, UniCamillus, Saint Camillus International University of Health and Medical Sciences, 00131 Rome, Italy
| | - Anastasia De Luca
- Department of Biomedicine and Prevention, Faculty of Medicine, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Ilenia Messia
- Department of Biomedicine and Prevention, Faculty of Medicine, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Antonietta Gentile
- Department of Biomedicine and Prevention, Faculty of Medicine, University of Rome Tor Vergata, 00133 Rome, Italy
- Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Roma, 00166 Rome, Italy
| | - Yunhee Kang
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Veronica Nobile
- Institute of Genomic Medicine, Fondazione Policlinico Universitario A. Gemelli Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Catholic University, 00168 Rome, Italy
| | - Elisabetta Tabolacci
- Institute of Genomic Medicine, Fondazione Policlinico Universitario A. Gemelli Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Catholic University, 00168 Rome, Italy
| | - Peng Jin
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Maria Giulia Farace
- Department of Biomedicine and Prevention, Faculty of Medicine, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Claudia Bagni
- Department of Biomedicine and Prevention, Faculty of Medicine, University of Rome Tor Vergata, 00133 Rome, Italy
- Department of Fundamental Neurosciences, Faculty of Biology and Medicine, University of Lausanne, 1005 Lausanne, Switzerland
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5
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Susco SG, Ghosh S, Mazzucato P, Angelini G, Beccard A, Barrera V, Berryer MH, Messana A, Lam D, Hazelbaker DZ, Barrett LE. Molecular convergence between Down syndrome and fragile X syndrome identified using human pluripotent stem cell models. Cell Rep 2022; 40:111312. [PMID: 36070702 PMCID: PMC9465809 DOI: 10.1016/j.celrep.2022.111312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 04/19/2022] [Accepted: 08/12/2022] [Indexed: 11/27/2022] Open
Abstract
Down syndrome (DS), driven by an extra copy of chromosome 21 (HSA21), and fragile X syndrome (FXS), driven by loss of the RNA-binding protein FMRP, are two common genetic causes of intellectual disability and autism. Based upon the number of DS-implicated transcripts bound by FMRP, we hypothesize that DS and FXS may share underlying mechanisms. Comparing DS and FXS human pluripotent stem cell (hPSC) and glutamatergic neuron models, we identify increased protein expression of select targets and overlapping transcriptional perturbations. Moreover, acute upregulation of endogenous FMRP in DS patient cells using CRISPRa is sufficient to significantly reduce expression levels of candidate proteins and reverse 40% of global transcriptional perturbations. These results pinpoint specific molecular perturbations shared between DS and FXS that can be leveraged as a strategy for target prioritization; they also provide evidence for the functional relevance of previous associations between FMRP targets and disease-implicated genes.
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Affiliation(s)
- Sara G Susco
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA
| | - Sulagna Ghosh
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Patrizia Mazzucato
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Gabriella Angelini
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Amanda Beccard
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Victor Barrera
- Bioinformatics Core, Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Martin H Berryer
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA
| | - Angelica Messana
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Daisy Lam
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Dane Z Hazelbaker
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Lindy E Barrett
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA.
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6
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Lizarazo S, Yook Y, Tsai N. Amyloid beta induces
Fmr1
‐dependent translational suppression and hyposynchrony of neural activity via phosphorylation of eIF2α and eEF2. J Cell Physiol 2022; 237:2929-2942. [PMID: 35434801 PMCID: PMC9283232 DOI: 10.1002/jcp.30754] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 03/25/2022] [Accepted: 03/30/2022] [Indexed: 01/02/2023]
Abstract
Alzheimer's disease (AD) is the most common cause of dementia, with the accumulation of amyloid beta peptide (Aβ) being one of the main causes of the disease. Fragile X mental retardation protein (FMRP), encoded by fragile X mental retardation 1 (Fmr1), is an RNA‐binding protein that represses translation of its bound mRNAs or exerts other indirect mechanisms that result in translational suppression. Because the accumulation of Aβ has been shown to cause translational suppression resulting from the elevated cellular stress response, in this study we asked whether and how Fmr1 is involved in Aβ‐induced translational regulation. Our data first showed that the application of synthetic Aβ peptide induces the expression of Fmr1 in cultured primary neurons. We followed by showing that Fmr1 is required for Aβ‐induced translational suppression, hyposynchrony of neuronal firing activity, and loss of excitatory synapses. Mechanistically, we revealed that Fmr1 functions to repress the expression of phosphatases including protein phosphatase 2A (PP2A) and protein phosphatase 1 (PP1), leading to elevated phosphorylation of eukaryotic initiation factor 2‐α (eIF2α) and eukaryotic elongation factor 2 (eEF2), and subsequent translational suppression. Finally, our data suggest that such translational suppression is critical to Aβ‐induced hyposynchrony of firing activity, but not the loss of synapses. Altogether, our study uncovers a novel mechanism by which Aβ triggers translational suppression and we reveal the participation of Fmr1 in altered neural plasticity associated with Aβ pathology. Our study may also provide information for a better understanding of Aβ‐induced cellular stress responses in AD.
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Affiliation(s)
- Simon Lizarazo
- Department of Molecular and Integrative Physiology, School of Molecular and Cellular Biology University of Illinois at Urbana‐Champaign Urbana Illinois USA
| | - Yeeun Yook
- Department of Molecular and Integrative Physiology, School of Molecular and Cellular Biology University of Illinois at Urbana‐Champaign Urbana Illinois USA
| | - Nien‐Pei Tsai
- Department of Molecular and Integrative Physiology, School of Molecular and Cellular Biology University of Illinois at Urbana‐Champaign Urbana Illinois USA
- Neuroscience Program University of Illinois at Urbana‐Champaign Urbana Illinois USA
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7
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Kim J, Kim S, Kim H, Hwang IW, Bae S, Karki S, Kim D, Ogelman R, Bang G, Kim JY, Kajander T, Um JW, Oh WC, Ko J. MDGA1 negatively regulates amyloid precursor protein-mediated synapse inhibition in the hippocampus. Proc Natl Acad Sci U S A 2022. [PMID: 35074912 DOI: 10.1073/pnas.2115326119/suppl_file/pnas.2115326119.sd01.xlsx] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2023] Open
Abstract
Balanced synaptic inhibition, controlled by multiple synaptic adhesion proteins, is critical for proper brain function. MDGA1 (meprin, A-5 protein, and receptor protein-tyrosine phosphatase mu [MAM] domain-containing glycosylphosphatidylinositol anchor protein 1) suppresses synaptic inhibition in mammalian neurons, yet the molecular mechanisms underlying MDGA1-mediated negative regulation of GABAergic synapses remain unresolved. Here, we show that the MDGA1 MAM domain directly interacts with the extension domain of amyloid precursor protein (APP). Strikingly, MDGA1-mediated synaptic disinhibition requires the MDGA1 MAM domain and is prominent at distal dendrites of hippocampal CA1 pyramidal neurons. Down-regulation of APP in presynaptic GABAergic interneurons specifically suppressed GABAergic, but not glutamatergic, synaptic transmission strength and inputs onto both the somatic and dendritic compartments of hippocampal CA1 pyramidal neurons. Moreover, APP deletion manifested differential effects in somatostatin- and parvalbumin-positive interneurons in the hippocampal CA1, resulting in distinct alterations in inhibitory synapse numbers, transmission, and excitability. The infusion of MDGA1 MAM protein mimicked postsynaptic MDGA1 gain-of-function phenotypes that involve the presence of presynaptic APP. The overexpression of MDGA1 wild type or MAM, but not MAM-deleted MDGA1, in the hippocampal CA1 impaired novel object-recognition memory in mice. Thus, our results establish unique roles of APP-MDGA1 complexes in hippocampal neural circuits, providing unprecedented insight into trans-synaptic mechanisms underlying differential tuning of neuronal compartment-specific synaptic inhibition.
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Affiliation(s)
- Jinhu Kim
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea
| | - Seungjoon Kim
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea
| | - Hyeonho Kim
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea
| | - In-Wook Hwang
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045
| | - Sungwon Bae
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea
| | - Sudeep Karki
- Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
| | - Dongwook Kim
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea
| | - Roberto Ogelman
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045
| | - Geul Bang
- Research Center for Bioconvergence Analysis, Korea Basic Science Institute, Ochang 305-732, Korea
| | - Jin Young Kim
- Research Center for Bioconvergence Analysis, Korea Basic Science Institute, Ochang 305-732, Korea
| | - Tommi Kajander
- Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
| | - Ji Won Um
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea
| | - Won Chan Oh
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045;
| | - Jaewon Ko
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea;
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8
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Kim J, Kim S, Kim H, Hwang IW, Bae S, Karki S, Kim D, Ogelman R, Bang G, Kim JY, Kajander T, Um JW, Oh WC, Ko J. MDGA1 negatively regulates amyloid precursor protein-mediated synapse inhibition in the hippocampus. Proc Natl Acad Sci U S A 2022; 119:e2115326119. [PMID: 35074912 PMCID: PMC8795569 DOI: 10.1073/pnas.2115326119] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 12/05/2021] [Indexed: 12/20/2022] Open
Abstract
Balanced synaptic inhibition, controlled by multiple synaptic adhesion proteins, is critical for proper brain function. MDGA1 (meprin, A-5 protein, and receptor protein-tyrosine phosphatase mu [MAM] domain-containing glycosylphosphatidylinositol anchor protein 1) suppresses synaptic inhibition in mammalian neurons, yet the molecular mechanisms underlying MDGA1-mediated negative regulation of GABAergic synapses remain unresolved. Here, we show that the MDGA1 MAM domain directly interacts with the extension domain of amyloid precursor protein (APP). Strikingly, MDGA1-mediated synaptic disinhibition requires the MDGA1 MAM domain and is prominent at distal dendrites of hippocampal CA1 pyramidal neurons. Down-regulation of APP in presynaptic GABAergic interneurons specifically suppressed GABAergic, but not glutamatergic, synaptic transmission strength and inputs onto both the somatic and dendritic compartments of hippocampal CA1 pyramidal neurons. Moreover, APP deletion manifested differential effects in somatostatin- and parvalbumin-positive interneurons in the hippocampal CA1, resulting in distinct alterations in inhibitory synapse numbers, transmission, and excitability. The infusion of MDGA1 MAM protein mimicked postsynaptic MDGA1 gain-of-function phenotypes that involve the presence of presynaptic APP. The overexpression of MDGA1 wild type or MAM, but not MAM-deleted MDGA1, in the hippocampal CA1 impaired novel object-recognition memory in mice. Thus, our results establish unique roles of APP-MDGA1 complexes in hippocampal neural circuits, providing unprecedented insight into trans-synaptic mechanisms underlying differential tuning of neuronal compartment-specific synaptic inhibition.
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Affiliation(s)
- Jinhu Kim
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea
| | - Seungjoon Kim
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea
| | - Hyeonho Kim
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea
| | - In-Wook Hwang
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045
| | - Sungwon Bae
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea
| | - Sudeep Karki
- Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
| | - Dongwook Kim
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea
| | - Roberto Ogelman
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045
| | - Geul Bang
- Research Center for Bioconvergence Analysis, Korea Basic Science Institute, Ochang 305-732, Korea
| | - Jin Young Kim
- Research Center for Bioconvergence Analysis, Korea Basic Science Institute, Ochang 305-732, Korea
| | - Tommi Kajander
- Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
| | - Ji Won Um
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea
| | - Won Chan Oh
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045;
| | - Jaewon Ko
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea;
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9
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Westmark PR, Garrone B, Ombrato R, Milanese C, Di Giorgio FP, Westmark CJ. Testing Fmr1 KO Phenotypes in Response to GSK3 Inhibitors: SB216763 versus AFC03127. Front Mol Neurosci 2021; 14:751307. [PMID: 34690696 PMCID: PMC8529056 DOI: 10.3389/fnmol.2021.751307] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 09/15/2021] [Indexed: 11/15/2022] Open
Abstract
Glycogen synthase kinase 3 (GSK3) is a proline-directed serine-threonine kinase that is associated with several neurological disorders, including Alzheimer’s disease and fragile X syndrome (FXS). We tested the efficacy of a novel GSK3 inhibitor AFC03127, which was developed by Angelini Pharma, in comparison to the metabotropic glutamate receptor 5 inhibitor 2-Methyl-6-(phenylethynyl)pyridine hydrochloride (MPEP) and the GSK3 inhibitor SB216763 in in vivo and in vitro assays in Fmr1KO mice, a mouse model useful for the study of FXS. The in vivo assay tested susceptibility to audiogenic-induced seizures (AGS) whereas the in vitro assays assessed biomarker expression and dendritic spine length and density in cultured primary neurons as a function of drug dose. MPEP and SB216763 attenuated AGS in Fmr1KO mice, whereas AFC03127 did not. MPEP and AFC03127 significantly reduced dendritic expression of amyloid-beta protein precursor (APP). All drugs rescued spine length and the ratio of mature dendritic spines. Spine density was not statistically different between vehicle and GSK3 inhibitor-treated cells. The drugs were tested over a wide concentration range in the in vitro assays to determine dose responses. A bell-shaped dose response decrease in APP expression was observed in response to AFC03127, which was more effective than SB216763. These findings confirm previous studies demonstrating differential effects of various GSK3 inhibitors on AGS propensity in Fmr1KO mice and confirm APP as a downstream biomarker that is responsive to GSK3 activity.
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Affiliation(s)
- Pamela R Westmark
- Department of Neurology, University of Wisconsin, Madison, WI, United States
| | | | | | | | | | - Cara J Westmark
- Department of Neurology, University of Wisconsin, Madison, WI, United States.,Molecular and Environmental Toxicology Center, University of Wisconsin, Madison, WI, United States
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10
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Filon MJ, Wallace E, Wright S, Douglas DJ, Steinberg LI, Verkuilen CL, Westmark PR, Maganti RK, Westmark CJ. Sleep and diurnal rest-activity rhythm disturbances in a mouse model of Alzheimer's disease. Sleep 2021; 43:5830779. [PMID: 32369586 DOI: 10.1093/sleep/zsaa087] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 04/07/2020] [Indexed: 01/08/2023] Open
Abstract
STUDY OBJECTIVES Accumulating evidence suggests a strong association between sleep, amyloid-beta (Aβ) deposition, and Alzheimer's disease (AD). We sought to determine if (1) deficits in rest-activity rhythms and sleep are significant phenotypes in J20 AD mice, (2) metabotropic glutamate receptor 5 inhibitors (mGluR5) could rescue deficits in rest-activity rhythms and sleep, and (3) Aβ levels are responsive to treatment with mGluR5 inhibitors. METHODS Diurnal rest-activity levels were measured by actigraphy and sleep-wake patterns by electroencephalography, while animals were chronically treated with mGluR5 inhibitors. Behavioral tests were performed, and Aβ levels measured in brain lysates. RESULTS J20 mice exhibited a 4.5-h delay in the acrophase of activity levels compared to wild-type littermates and spent less time in rapid eye movement (REM) sleep during the second half of the light period. J20 mice also exhibited decreased non-rapid eye movement (NREM) delta power but increased NREM sigma power. The mGluR5 inhibitor CTEP rescued the REM sleep deficit and improved NREM delta and sigma power but did not correct rest-activity rhythms. No statistically significant differences were observed in Aβ levels, rotarod performance, or the passive avoidance task following chronic mGluR5 inhibitor treatment. CONCLUSIONS J20 mice have disruptions in rest-activity rhythms and reduced homeostatic sleep pressure (reduced NREM delta power). NREM delta power was increased following treatment with a mGluR5 inhibitor. Drug bioavailability was poor. Further work is necessary to determine if mGluR5 is a viable target for treating sleep phenotypes in AD.
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Affiliation(s)
- Mikolaj J Filon
- Department of Neurology, University of Wisconsin-Madison, Madison, WI
| | - Eli Wallace
- Department of Neurology, University of Wisconsin-Madison, Madison, WI
| | - Samantha Wright
- Department of Neurology, University of Wisconsin-Madison, Madison, WI
| | - Dylan J Douglas
- Department of Neurology, University of Wisconsin-Madison, Madison, WI
| | | | | | - Pamela R Westmark
- Department of Neurology, University of Wisconsin-Madison, Madison, WI
| | - Rama K Maganti
- Department of Neurology, University of Wisconsin-Madison, Madison, WI
| | - Cara J Westmark
- Department of Neurology, University of Wisconsin-Madison, Madison, WI
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11
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Motanis H, Buonomano D. Decreased reproducibility and abnormal experience-dependent plasticity of network dynamics in Fragile X circuits. Sci Rep 2020; 10:14535. [PMID: 32884028 PMCID: PMC7471942 DOI: 10.1038/s41598-020-71333-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 08/10/2020] [Indexed: 02/06/2023] Open
Abstract
Fragile X syndrome is a neurodevelopmental disorder associated with a broad range of neural phenotypes. Interpreting these findings has proven challenging because some phenotypes may reflect compensatory mechanisms or normal forms of plasticity differentially engaged by experiential differences. To help minimize compensatory and experiential influences, we used an ex vivo approach to study network dynamics and plasticity of cortical microcircuits. In Fmr1-/y circuits, the spatiotemporal structure of Up-states was less reproducible, suggesting alterations in the plasticity mechanisms governing network activity. Chronic optical stimulation revealed normal homeostatic plasticity of Up-states, however, Fmr1-/y circuits exhibited abnormal experience-dependent plasticity as they did not adapt to chronically presented temporal patterns in an interval-specific manner. These results, suggest that while homeostatic plasticity is normal, Fmr1-/y circuits exhibit deficits in the ability to orchestrate multiple forms of synaptic plasticity and to adapt to sensory patterns in an experience-dependent manner-which is likely to contribute to learning deficits.
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Affiliation(s)
- Helen Motanis
- Departments of Neurobiology and Psychology, and Integrative Center for Learning and Memory, University of California, 630 Charles E Young Dr S, Center for Health Sciences Building, Los Angeles, CA, 90095, USA
| | - Dean Buonomano
- Departments of Neurobiology and Psychology, and Integrative Center for Learning and Memory, University of California, 630 Charles E Young Dr S, Center for Health Sciences Building, Los Angeles, CA, 90095, USA.
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12
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Gourmaud S, Shou H, Irwin DJ, Sansalone K, Jacobs LM, Lucas TH, Marsh ED, Davis KA, Jensen FE, Talos DM. Alzheimer-like amyloid and tau alterations associated with cognitive deficit in temporal lobe epilepsy. Brain 2020; 143:191-209. [PMID: 31834353 DOI: 10.1093/brain/awz381] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 10/08/2019] [Accepted: 10/17/2019] [Indexed: 01/27/2023] Open
Abstract
Temporal lobe epilepsy represents a major cause of drug-resistant epilepsy. Cognitive impairment is a frequent comorbidity, but the mechanisms are not fully elucidated. We hypothesized that the cognitive impairment in drug-resistant temporal lobe epilepsy could be due to perturbations of amyloid and tau signalling pathways related to activation of stress kinases, similar to those observed in Alzheimer's disease. We examined these pathways, as well as amyloid-β and tau pathologies in the hippocampus and temporal lobe cortex of drug-resistant temporal lobe epilepsy patients who underwent temporal lobe resection (n = 19), in comparison with age- and region-matched samples from neurologically normal autopsy cases (n = 22). Post-mortem temporal cortex samples from Alzheimer's disease patients (n = 9) were used as positive controls to validate many of the neurodegeneration-related antibodies. Western blot and immunohistochemical analysis of tissue from temporal lobe epilepsy cases revealed increased phosphorylation of full-length amyloid precursor protein and its associated neurotoxic cleavage product amyloid-β*56. Pathological phosphorylation of two distinct tau species was also increased in both regions, but increases in amyloid-β1-42 peptide, the main component of amyloid plaques, were restricted to the hippocampus. Furthermore, several major stress kinases involved in the development of Alzheimer's disease pathology were significantly activated in temporal lobe epilepsy brain samples, including the c-Jun N-terminal kinase and the protein kinase R-like endoplasmic reticulum kinase. In temporal lobe epilepsy cases, hippocampal levels of phosphorylated amyloid precursor protein, its pro-amyloidogenic processing enzyme beta-site amyloid precursor protein cleaving enzyme 1, and both total and hyperphosphorylated tau expression, correlated with impaired preoperative executive function. Our study suggests that neurodegenerative and stress-related processes common to those observed in Alzheimer's disease may contribute to cognitive impairment in drug-resistant temporal lobe epilepsy. In particular, we identified several stress pathways that may represent potential novel therapeutic targets.
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Affiliation(s)
- Sarah Gourmaud
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Haochang Shou
- Department of Biostatistics, Epidemiology and Informatics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - David J Irwin
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Penn Frontotemporal Degeneration Center, University of Pennsylvania, Philadelphia, PA, USA
| | - Kimberly Sansalone
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Leah M Jacobs
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Timothy H Lucas
- Department of Neurosurgery, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Eric D Marsh
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Division of Child Neurology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Kathryn A Davis
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Delia M Talos
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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13
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McCamphill PK, Stoppel LJ, Senter RK, Lewis MC, Heynen AJ, Stoppel DC, Sridhar V, Collins KA, Shi X, Pan JQ, Madison J, Cottrell JR, Huber KM, Scolnick EM, Holson EB, Wagner FF, Bear MF. Selective inhibition of glycogen synthase kinase 3α corrects pathophysiology in a mouse model of fragile X syndrome. Sci Transl Med 2020; 12:eaam8572. [PMID: 32434848 PMCID: PMC8095719 DOI: 10.1126/scitranslmed.aam8572] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 07/15/2019] [Accepted: 01/11/2020] [Indexed: 01/06/2023]
Abstract
Fragile X syndrome is caused by FMR1 gene silencing and loss of the encoded fragile X mental retardation protein (FMRP), which binds to mRNA and regulates translation. Studies in the Fmr1-/y mouse model of fragile X syndrome indicate that aberrant cerebral protein synthesis downstream of metabotropic glutamate receptor 5 (mGluR5) signaling contributes to disease pathogenesis, but clinical trials using mGluR5 inhibitors were not successful. Animal studies suggested that treatment with lithium might be an alternative approach. Targets of lithium include paralogs of glycogen synthase kinase 3 (GSK3), and nonselective small-molecule inhibitors of these enzymes improved disease phenotypes in a fragile X syndrome mouse model. However, the potential therapeutic use of GSK3 inhibitors has been hampered by toxicity arising from inhibition of both α and β paralogs. Recently, we developed GSK3 inhibitors with sufficient paralog selectivity to avoid a known toxic consequence of dual inhibition, that is, increased β-catenin stabilization. We show here that inhibition of GSK3α, but not GSK3β, corrected aberrant protein synthesis, audiogenic seizures, and sensory cortex hyperexcitability in Fmr1-/y mice. Although inhibiting either paralog prevented induction of NMDA receptor-dependent long-term depression (LTD) in the hippocampus, only inhibition of GSK3α impaired mGluR5-dependent and protein synthesis-dependent LTD. Inhibition of GSK3α additionally corrected deficits in learning and memory in Fmr1-/y mice; unlike mGluR5 inhibitors, there was no evidence of tachyphylaxis or enhanced psychotomimetic-induced hyperlocomotion. GSK3α selective inhibitors may have potential as a therapeutic approach for treating fragile X syndrome.
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Affiliation(s)
- Patrick K McCamphill
- Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Laura J Stoppel
- Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Rebecca K Senter
- Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Michael C Lewis
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Arnold J Heynen
- Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - David C Stoppel
- Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Vinay Sridhar
- University of Texas Southwestern Medical Center, Department of Neuroscience, Dallas, TX 75390, USA
| | - Katie A Collins
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Xi Shi
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Jen Q Pan
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Jon Madison
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Jeffrey R Cottrell
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Kimberly M Huber
- University of Texas Southwestern Medical Center, Department of Neuroscience, Dallas, TX 75390, USA
| | - Edward M Scolnick
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Edward B Holson
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Florence F Wagner
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
| | - Mark F Bear
- Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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14
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Kanyo R, Leighton PLA, Neil GJ, Locskai LF, Allison WT. Amyloid-β precursor protein mutant zebrafish exhibit seizure susceptibility that depends on prion protein. Exp Neurol 2020; 328:113283. [PMID: 32165257 DOI: 10.1016/j.expneurol.2020.113283] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 02/03/2020] [Accepted: 03/08/2020] [Indexed: 12/11/2022]
Abstract
It has been proposed that Amyloid β Precursor Protein (APP) might act as a rheostat controlling neuronal excitability, but mechanisms have remained untested. APP and its catabolite Aβ are known to impact upon synapse function and dysfunction via their interaction with the prion protein (PrPC), suggesting a candidate pathway. Here we test if PrPC is required for this APP function in vivo, perhaps via modulating mGluR5 ion channels. We engineered zebrafish to lack homologs of PrPC and APP, allowing us to assess their purported genetic and physiological interactions in CNS development. We generated four appa null alleles as well as prp1-/-;appa-/- double mutants (engineering of prp1 mutant alleles is described elsewhere). Unexpectedly, appa-/- and compound prp1-/-;appa-/- mutants are viable and lacked overt phenotypes (except being slightly smaller than wildtype fish at some developmental stages). Zebrafish prp1-/- mutants were substantially more sensitive to appa knockdown than wildtype fish, and both zebrafish prp1 and mammalian Prnp mRNA were significantly able to partially rescue this effect. Further, appa-/- mutants exhibited increased seizures upon exposure to low doses of convulsant. The mechanism of this seizure susceptibility requires prp1 insomuch that seizures were significantly dampened to wildtype levels in prp1-/-;appa-/- mutants. Inhibiting mGluR5 channels, which may be downstream of PrPC, increased seizure intensity only in prp1-/- mutants, and this seizure mechanism required intact appa. Taken together, these results support an intriguing genetic interaction between prp1 and appa with their shared roles impacting upon neuron hyperexcitability, thus complementing and extending past works detailing their biochemical interaction(s).
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Affiliation(s)
- Richard Kanyo
- Centre for Prions & Protein Folding Disease, University of Alberta, Edmonton, AB T6G 2M8, Canada; Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Patricia L A Leighton
- Centre for Prions & Protein Folding Disease, University of Alberta, Edmonton, AB T6G 2M8, Canada; Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Gavin J Neil
- Centre for Prions & Protein Folding Disease, University of Alberta, Edmonton, AB T6G 2M8, Canada; Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Laszlo F Locskai
- Centre for Prions & Protein Folding Disease, University of Alberta, Edmonton, AB T6G 2M8, Canada; Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - W Ted Allison
- Centre for Prions & Protein Folding Disease, University of Alberta, Edmonton, AB T6G 2M8, Canada; Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada; Department of Medical Genetics, University of Alberta, Edmonton, AB T6G 2H7, Canada.
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15
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McLane RD, Schmitt LM, Pedapati EV, Shaffer RC, Dominick KC, Horn PS, Gross C, Erickson CA. Peripheral Amyloid Precursor Protein Derivative Expression in Fragile X Syndrome. Front Integr Neurosci 2019; 13:49. [PMID: 31551722 PMCID: PMC6733993 DOI: 10.3389/fnint.2019.00049] [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] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 08/16/2019] [Indexed: 01/08/2023] Open
Abstract
Fragile X syndrome (FXS) is the most common inherited form of intellectual disability and is associated with increased risk for autism spectrum disorder (ASD), anxiety, ADHD, and epilepsy. While our understanding of FXS pathophysiology has improved, a lack of validated blood-based biomarkers of disease continues to impede bench-to-bedside efforts. To meet this demand, there is a growing effort to discover a reliable biomarker to inform treatment discovery and evaluate treatment target engagement. Such a marker, amyloid-beta precursor protein (APP), has shown potential dysregulation in the absence of fragile X mental retardation protein (FMRP) and may therefore be associated with FXS pathophysiology. While APP is best understood in the context of Alzheimer disease, there is a growing body of evidence suggesting the molecule and its derivatives play a broader role in regulating neuronal hyperexcitability, a well-characterized phenotype in FXS. To evaluate the viability of APP as a peripheral biological marker in FXS, we conducted an exploratory ELISA-based evaluation of plasma APP-related species involving 27 persons with FXS (mean age: 22.0 ± 11.5) and 25 age- and sex-matched persons with neurotypical development (mean age: 21.1 ± 10.7). Peripheral levels of both Aβ(1–40) and Aβ(1–42) were increased, while sAPPα was significantly decreased in persons with FXS as compared to control participants. These results suggest that dysregulated APP processing, with potential preferential β-secretase processing, may be a readily accessible marker of FXS pathophysiology.
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Affiliation(s)
- Richard D McLane
- Division of Child and Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States
| | - Lauren M Schmitt
- Division of Developmental and Behavioral Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States
| | - Ernest V Pedapati
- Division of Child and Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States.,Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States.,Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Rebecca C Shaffer
- Division of Developmental and Behavioral Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States.,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Kelli C Dominick
- Division of Child and Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States.,Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Paul S Horn
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States
| | - Christina Gross
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States.,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Craig A Erickson
- Division of Child and Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States.,Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati College of Medicine, Cincinnati, OH, United States
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16
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Westmark CJ. Fragile X and APP: a Decade in Review, a Vision for the Future. Mol Neurobiol 2019; 56:3904-3921. [PMID: 30225775 PMCID: PMC6421119 DOI: 10.1007/s12035-018-1344-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 09/05/2018] [Indexed: 10/28/2022]
Abstract
Fragile X syndrome (FXS) is a devastating developmental disability that has profound effects on cognition, behavior, and seizure susceptibility. There are currently no treatments that target the underlying cause of the disorder, and recent clinical trials have been unsuccessful. In 2007, seminal work demonstrated that amyloid-beta protein precursor (APP) is dysregulated in Fmr1KO mice through a metabotropic glutamate receptor 5 (mGluR5)-dependent pathway. These findings raise the hypotheses that: (1) APP and/or APP metabolites are potential therapeutic targets as well as biomarkers for FXS and (2) mGluR5 inhibitors may be beneficial in the treatment of Alzheimer's disease. Herein, advances in the field over the past decade that have reproduced and greatly expanded upon these original findings are reviewed, and required experimentation to validate APP metabolites as potential disease biomarkers as well as therapeutic targets for FXS are discussed.
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Affiliation(s)
- Cara J Westmark
- Department of Neurology, University of Wisconsin-Madison, Medical Sciences Center, Room 3619, 1300 University Avenue, Madison, WI, USA.
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17
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Preparation of Synaptoneurosomes for the Study of Glutamate Receptor Function. Methods Mol Biol 2019. [PMID: 30707435 DOI: 10.1007/978-1-4939-9077-1_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
The use of synaptoneurosomes (SN) enables the detection of synaptic activity including the assessment of glutamate receptor function. SN are normally prepared by filtration and centrifugation methods. Here we review the preparation of SN by Percoll density gradient methodology for downstream applications that assesses glutamate receptor function such as measuring de novo protein synthesis. Major procedural steps include preparation of discontinuous Percoll-sucrose density gradients, collection of brain tissue, preparation of brain homogenates, isolation of synaptoneurosome bands from the discontinuous Percoll-sucrose gradients, and radiolabeling SN proteins. De novo protein synthesis can be reproducibly measured in SN prepared by this method.
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18
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Schmitt LM, Shaffer RC, Hessl D, Erickson C. Executive Function in Fragile X Syndrome: A Systematic Review. Brain Sci 2019; 9:E15. [PMID: 30654486 PMCID: PMC6356760 DOI: 10.3390/brainsci9010015] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Revised: 01/09/2019] [Accepted: 01/11/2019] [Indexed: 12/17/2022] Open
Abstract
Executive function (EF) supports goal-directed behavior and includes key aspects such as working memory, inhibitory control, cognitive flexibility, attention, processing speed, and planning. Fragile X syndrome (FXS) is the leading inherited monogenic cause of intellectual disability and is phenotypically characterized by EF deficits beyond what is expected given general cognitive impairments. Yet, a systematic review of behavioral studies using performance-based measures is needed to provide a summary of EF deficits across domains in males and females with FXS, discuss clinical and biological correlates of these EF deficits, identify critical limitations in available research, and offer suggestions for future studies in this area. Ultimately, this review aims to advance our understanding of the underlying pathophysiological mechanisms contributing to EF in FXS and to inform the development of outcome measures of EF and identification of new treatment targets in FXS.
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Affiliation(s)
- Lauren M Schmitt
- Division of Child and Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA.
| | - Rebecca C Shaffer
- Division of Developmental and Behavioral Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA.
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA.
| | - David Hessl
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California, Davis, CA 95616, USA.
| | - Craig Erickson
- Division of Child and Adolescent Psychiatry, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA.
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA.
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19
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Impaired GABA Neural Circuits Are Critical for Fragile X Syndrome. Neural Plast 2018; 2018:8423420. [PMID: 30402088 PMCID: PMC6192167 DOI: 10.1155/2018/8423420] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 09/17/2018] [Indexed: 12/24/2022] Open
Abstract
Fragile X syndrome (FXS) is an inheritable neuropsychological disease caused by silence of the fmr1 gene and the deficiency of Fragile X mental retardation protein (FMRP). Patients present neuronal alterations that lead to severe intellectual disability and altered sleep rhythms. However, the neural circuit mechanisms underlying FXS remain unclear. Previous studies have suggested that metabolic glutamate and gamma-aminobutyric acid (GABA) receptors/circuits are two counter-balanced factors involved in FXS pathophysiology. More and more studies demonstrated that attenuated GABAergic circuits in the absence of FMRP are critical for abnormal progression of FXS. Here, we reviewed the changes of GABA neural circuits that were attributed to intellectual-deficient FXS, from several aspects including deregulated GABA metabolism, decreased expressions of GABA receptor subunits, and impaired GABAergic neural circuits. Furthermore, the activities of GABA neural circuits are modulated by circadian rhythm of FMRP metabolism and reviewed the abnormal condition of FXS mice or patients.
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20
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Westmark PR, Dekundy A, Gravius A, Danysz W, Westmark CJ. Rescue of Fmr1 KO phenotypes with mGluR 5 inhibitors: MRZ-8456 versus AFQ-056. Neurobiol Dis 2018; 119:190-198. [PMID: 30125640 DOI: 10.1016/j.nbd.2018.08.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Revised: 08/08/2018] [Accepted: 08/13/2018] [Indexed: 12/23/2022] Open
Abstract
Metabotropic glutamate receptor 5 (mGluR5) is a drug target for central nervous system disorders such as fragile X syndrome that involve excessive glutamate-induced excitation. We tested the efficacy of a novel negative allosteric modulator of mGluR5 developed by Merz Pharmaceuticals, MRZ-8456, in comparison to MPEP and AFQ-056 (Novartis, a.k.a. mavoglurant) in both in vivo and in vitro assays in a mouse model of fragile X syndrome, Fmr1KO mice. The in vivo assays included susceptibility to audiogenic-induced seizures and pharmacokinetic measurements of drug availability. The in vitro assays included dose response assessments of biomarker expression and dendritic spine length and density in cultured primary neurons. Both MRZ-8456 and AFQ-056 attenuated wild running and audiogenic-induced seizures in Fmr1KO mice with similar pharmacokinetic profiles. Both drugs significantly reduced dendritic expression of amyloid-beta protein precursor (APP) and rescued the ratio of mature to immature dendritic spines. These findings demonstrate that MRZ-8456, a drug being developed for the treatment of motor complications of L-DOPA in Parkinson's disease and which completed a phase I clinical trial, is effective in attenuating both well-established (seizures and dendritic spine maturity) and exploratory biomarker (APP expression) phenotypes in a mouse model of fragile X syndrome.
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Affiliation(s)
- Pamela R Westmark
- University of Wisconsin-Madison, Department of Neurology, Madison, WI, USA; University of Wisconsin-Madison, Department of Medicine, Madison, WI, USA
| | - Andrzej Dekundy
- Merz Pharmaceuticals GmbH, Eckenheimer Landstrasse 100, 60318 Frankfurt am Main, Germany
| | - Andreas Gravius
- Merz Pharmaceuticals GmbH, Eckenheimer Landstrasse 100, 60318 Frankfurt am Main, Germany
| | - Wojciech Danysz
- Merz Pharmaceuticals GmbH, Eckenheimer Landstrasse 100, 60318 Frankfurt am Main, Germany
| | - Cara J Westmark
- University of Wisconsin-Madison, Department of Neurology, Madison, WI, USA.
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21
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Dahlhaus R. Of Men and Mice: Modeling the Fragile X Syndrome. Front Mol Neurosci 2018; 11:41. [PMID: 29599705 PMCID: PMC5862809 DOI: 10.3389/fnmol.2018.00041] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 01/31/2018] [Indexed: 12/26/2022] Open
Abstract
The Fragile X Syndrome (FXS) is one of the most common forms of inherited intellectual disability in all human societies. Caused by the transcriptional silencing of a single gene, the fragile x mental retardation gene FMR1, FXS is characterized by a variety of symptoms, which range from mental disabilities to autism and epilepsy. More than 20 years ago, a first animal model was described, the Fmr1 knock-out mouse. Several other models have been developed since then, including conditional knock-out mice, knock-out rats, a zebrafish and a drosophila model. Using these model systems, various targets for potential pharmaceutical treatments have been identified and many treatments have been shown to be efficient in preclinical studies. However, all attempts to turn these findings into a therapy for patients have failed thus far. In this review, I will discuss underlying difficulties and address potential alternatives for our future research.
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Affiliation(s)
- Regina Dahlhaus
- Institute for Biochemistry, Emil-Fischer Centre, University of Erlangen-Nürnberg, Erlangen, Germany
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22
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Davis JK, Broadie K. Multifarious Functions of the Fragile X Mental Retardation Protein. Trends Genet 2017; 33:703-714. [PMID: 28826631 PMCID: PMC5610095 DOI: 10.1016/j.tig.2017.07.008] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 07/20/2017] [Accepted: 07/24/2017] [Indexed: 01/01/2023]
Abstract
Fragile X syndrome (FXS), a heritable intellectual and autism spectrum disorder (ASD), results from the loss of Fragile X mental retardation protein (FMRP). This neurodevelopmental disease state exhibits neural circuit hyperconnectivity and hyperexcitability. Canonically, FMRP functions as an mRNA-binding translation suppressor, but recent findings have enormously expanded its proposed roles. Although connections between burgeoning FMRP functions remain unknown, recent advances have extended understanding of its involvement in RNA, channel, and protein binding that modulate calcium signaling, activity-dependent critical period development, and the excitation-inhibition (E/I) neural circuitry balance. In this review, we contextualize 3 years of FXS model research. Future directions extrapolated from recent advances focus on discovering links between FMRP roles to determine whether FMRP has a multitude of unrelated functions or whether combinatorial mechanisms can explain its multifaceted existence.
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Affiliation(s)
- Jenna K Davis
- Department of Biological Sciences, Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, TN 37235, USA
| | - Kendal Broadie
- Department of Biological Sciences, Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, TN 37235, USA.
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23
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Kazim SF, Chuang SC, Zhao W, Wong RKS, Bianchi R, Iqbal K. Early-Onset Network Hyperexcitability in Presymptomatic Alzheimer's Disease Transgenic Mice Is Suppressed by Passive Immunization with Anti-Human APP/Aβ Antibody and by mGluR5 Blockade. Front Aging Neurosci 2017; 9:71. [PMID: 28392767 PMCID: PMC5364175 DOI: 10.3389/fnagi.2017.00071] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Accepted: 03/08/2017] [Indexed: 11/26/2022] Open
Abstract
Cortical and hippocampal network hyperexcitability appears to be an early event in Alzheimer’s disease (AD) pathogenesis, and may contribute to memory impairment. It remains unclear if network hyperexcitability precedes memory impairment in mouse models of AD and what are the underlying cellular mechanisms. We thus evaluated seizure susceptibility and hippocampal network hyperexcitability at ~3 weeks of age [prior to amyloid beta (Aβ) plaque deposition, neurofibrillary pathology, and cognitive impairment] in a triple transgenic mouse model of familial AD (3xTg-AD mouse) that harbors mutated human Aβ precursor protein (APP), tau and presenilin 1 (PS1) genes. Audiogenic seizures were elicited in a higher proportion of 3xTg-AD mice compared with wild type (WT) controls. Seizure susceptibility in 3xTg-AD mice was attenuated either by passive immunization with anti-human APP/Aβ antibody (6E10) or by blockade of metabotropic glutamate receptor 5 (mGluR5) with the selective antagonist, 2-methyl-6-(phenylethynyl)pyridine hydrochloride (MPEP). In in vitro hippocampal slices, suppression of synaptic inhibition with the GABAA receptor antagonist, bicuculline, induced prolonged epileptiform (>1.5 s in duration) ictal-like discharges in the CA3 neuronal network in the majority of the slices from 3xTg-AD mice. In contrast, only short epileptiform (<1.5 s in duration) interictal-like discharges were observed following bicuculline application in the CA3 region of WT slices. The ictal-like activity in CA3 region of the hippocampus was significantly reduced in the 6E10-immunized compared to the saline-treated 3xTg-AD mice. MPEP acutely suppressed the ictal-like discharges in 3xTg-AD slices. Remarkably, epileptiform discharge duration positively correlated with intraneuronal human (transgenic) APP/Aβ expression in the CA3 region of the hippocampus. Our data suggest that in a mouse model of familial AD, hypersynchronous network activity underlying seizure susceptibility precedes Aβ plaque pathology and memory impairment. This early-onset network hyperexcitability can be suppressed by passive immunization with an anti-human APP/Aβ antibody and by mGluR5 blockade in 3xTg-AD mice.
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Affiliation(s)
- Syed F Kazim
- Robert F. Furchgott Center for Neural and Behavioral Science and Department of Physiology and Pharmacology, State University of New York (SUNY) Downstate Medical CenterBrooklyn, NY, USA; Department of Neurochemistry and SUNY Downstate/NYSIBR Center for Developmental Neuroscience, New York State Institute for Basic Research (NYSIBR)Staten Island, NY, USA; Graduate Program in Neural and Behavioral Science, SUNY Downstate Medical CenterBrooklyn, NY, USA
| | - Shih-Chieh Chuang
- Robert F. Furchgott Center for Neural and Behavioral Science and Department of Physiology and Pharmacology, State University of New York (SUNY) Downstate Medical Center Brooklyn, NY, USA
| | - Wangfa Zhao
- Robert F. Furchgott Center for Neural and Behavioral Science and Department of Physiology and Pharmacology, State University of New York (SUNY) Downstate Medical Center Brooklyn, NY, USA
| | - Robert K S Wong
- Robert F. Furchgott Center for Neural and Behavioral Science and Department of Physiology and Pharmacology, State University of New York (SUNY) Downstate Medical Center Brooklyn, NY, USA
| | - Riccardo Bianchi
- Robert F. Furchgott Center for Neural and Behavioral Science and Department of Physiology and Pharmacology, State University of New York (SUNY) Downstate Medical Center Brooklyn, NY, USA
| | - Khalid Iqbal
- Department of Neurochemistry and SUNY Downstate/NYSIBR Center for Developmental Neuroscience, New York State Institute for Basic Research (NYSIBR) Staten Island, NY, USA
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