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Rastogi M, Bartolucci M, Nanni M, Aloisio M, Vozzi D, Petretto A, Contestabile A, Cancedda L. Integrative multi-omic analysis reveals conserved cell-projection deficits in human Down syndrome brains. Neuron 2024; 112:2503-2523.e10. [PMID: 38810652 DOI: 10.1016/j.neuron.2024.05.002] [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: 01/02/2023] [Revised: 03/17/2024] [Accepted: 05/01/2024] [Indexed: 05/31/2024]
Abstract
Down syndrome (DS) is the most common genetic cause of cognitive disability. However, it is largely unclear how triplication of a small gene subset may impinge on diverse aspects of DS brain physiopathology. Here, we took a multi-omic approach and simultaneously analyzed by RNA-seq and proteomics the expression signatures of two diverse regions of human postmortem DS brains. We found that the overexpression of triplicated genes triggered global expression dysregulation, differentially affecting transcripts, miRNAs, and proteins involved in both known and novel biological candidate pathways. Among the latter, we observed an alteration in RNA splicing, specifically modulating the expression of genes involved in cytoskeleton and axonal dynamics in DS brains. Accordingly, we found an alteration in axonal polarization in neurons from DS human iPSCs and mice. Thus, our study provides an integrated multilayer expression database capable of identifying new potential targets to aid in designing future clinical interventions for DS.
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Affiliation(s)
- Mohit Rastogi
- Brain Development and Disease Laboratory, Istituto Italiano di Tecnologia, Genova 16163, Italy
| | - Martina Bartolucci
- Core Facilities - Clinical Proteomics and Metabolomics, IRCCS Istituto Giannina Gaslini, Genova 16147, Italy
| | - Marina Nanni
- Brain Development and Disease Laboratory, Istituto Italiano di Tecnologia, Genova 16163, Italy
| | | | - Diego Vozzi
- Central RNA Laboratory, Istituto Italiano di Tecnologia, Genova 16152, Italy
| | - Andrea Petretto
- Core Facilities - Clinical Proteomics and Metabolomics, IRCCS Istituto Giannina Gaslini, Genova 16147, Italy
| | - Andrea Contestabile
- Brain Development and Disease Laboratory, Istituto Italiano di Tecnologia, Genova 16163, Italy.
| | - Laura Cancedda
- Brain Development and Disease Laboratory, Istituto Italiano di Tecnologia, Genova 16163, Italy; Dulbecco Telethon Institute, Rome 00185, Italy.
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Chmiel J, Rybakowski F, Leszek J. EEG in Down Syndrome-A Review and Insights into Potential Neural Mechanisms. Brain Sci 2024; 14:136. [PMID: 38391711 PMCID: PMC10886507 DOI: 10.3390/brainsci14020136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Revised: 01/23/2024] [Accepted: 01/26/2024] [Indexed: 02/24/2024] Open
Abstract
Introduction: Down syndrome (DS) stands out as one of the most prevalent genetic disorders, imposing a significant burden on both society and the healthcare system. Scientists are making efforts to understand the neural mechanisms behind the pathophysiology of this disorder. Among the valuable methods for studying these mechanisms is electroencephalography (EEG), a non-invasive technique that measures the brain's electrical activity, characterised by its excellent temporal resolution. This review aims to consolidate studies examining EEG usage in individuals with DS. The objective was to identify shared elements of disrupted EEG activity and, crucially, to elucidate the neural mechanisms underpinning these deviations. Searches were conducted on Pubmed/Medline, Research Gate, and Cochrane databases. Results: The literature search yielded 17 relevant articles. Despite the significant time span, small sample size, and overall heterogeneity of the included studies, three common features of aberrant EEG activity in people with DS were found. Potential mechanisms for this altered activity were delineated. Conclusions: The studies included in this review show altered EEG activity in people with DS compared to the control group. To bolster these current findings, future investigations with larger sample sizes are imperative.
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Affiliation(s)
- James Chmiel
- Institute of Neurofeedback and tDCS Poland, 70-393 Szczecin, Poland
| | - Filip Rybakowski
- Department and Clinic of Psychiatry, Poznan University of Medical Sciences, 61-701 Poznań, Poland
| | - Jerzy Leszek
- Department and Clinic of Psychiatry, Wrocław Medical University, 54-235 Wrocław, Poland
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3
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Thomazeau A, Lassalle O, Manzoni OJ. Glutamatergic synaptic deficits in the prefrontal cortex of the Ts65Dn mouse model for Down syndrome. Front Neurosci 2023; 17:1171797. [PMID: 37841687 PMCID: PMC10569174 DOI: 10.3389/fnins.2023.1171797] [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: 02/22/2023] [Accepted: 09/11/2023] [Indexed: 10/17/2023] Open
Abstract
Down syndrome (DS), the most prevalent cause of intellectual disability, stems from a chromosomal anomaly resulting in an entire or partial extra copy of chromosome 21. This leads to intellectual disability and a range of associated symptoms. While there has been considerable research focused on the Ts65Dn mouse model of DS, particularly in the context of the hippocampus, the synaptic underpinnings of prefrontal cortex (PFC) dysfunction in DS, including deficits in working memory, remain largely uncharted territory. In a previous study featuring mBACtgDyrk1a mice, which manifest overexpression of the Dyrk1a gene, a known candidate gene linked to intellectual disability and microcephaly in DS, we documented adverse effects on spine density, alterations in the molecular composition of synapses, and the presence of synaptic plasticity deficits within the PFC. The current study aimed to enrich our understanding of the roles of different genes in DS by studying Ts65Dn mice, which overexpress several genes including Dyrk1a, to compare with our previous work on mBACtgDyrk1a mice. Through ex-vivo electrophysiological experiments, including patch-clamp and extracellular field potential recordings, we identified alterations in the intrinsic properties of PFC layer V/VI pyramidal neurons in Ts65Dn male mice. Additionally, we observed changes in the synaptic plasticity range. Notably, long-term depression was absent in Ts65Dn mice, while synaptic or pharmacological long-term potentiation remained fully expressed in these mice. These findings provide valuable insights into the intricate synaptic mechanisms contributing to PFC dysfunction in DS, shedding light on potential therapeutic avenues for addressing the neurocognitive symptoms associated with this condition.
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Affiliation(s)
- Aurore Thomazeau
- Côte d’Azur, CNRS UMR7275, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne, France
- Université Aix-Marseille, Marseille, France
- INMED, INSERM U1249, Marseille, France
| | - Olivier Lassalle
- Université Aix-Marseille, Marseille, France
- INMED, INSERM U1249, Marseille, France
| | - Olivier J. Manzoni
- Université Aix-Marseille, Marseille, France
- INMED, INSERM U1249, Marseille, France
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4
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Seol S, Kwon J, Kang HJ. Cell type characterization of spatiotemporal gene co-expression modules in Down syndrome brain. iScience 2022; 26:105884. [PMID: 36647384 PMCID: PMC9840153 DOI: 10.1016/j.isci.2022.105884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 11/02/2022] [Accepted: 12/22/2022] [Indexed: 12/29/2022] Open
Abstract
Down syndrome (DS) is the most common genetic cause of intellectual disability and increases the risk of other brain-related dysfunctions, like seizures, early-onset Alzheimer's disease, and autism. To reveal the molecular profiles of DS-associated brain phenotypes, we performed a meta-data analysis of the developmental DS brain transcriptome at cell type and co-expression module levels. In the DS brain, astrocyte-, microglia-, and endothelial cell-associated genes show upregulated patterns, whereas neuron- and oligodendrocyte-associated genes show downregulated patterns. Weighted gene co-expression network analysis identified cell type-enriched co-expressed gene modules. We present eight representative cell-type modules for neurons, astrocytes, oligodendrocytes, and microglia. We classified the neuron modules into glutamatergic and GABAergic neurons and associated them with detailed subtypes. Cell type modules were interpreted by analyzing spatiotemporal expression patterns, functional annotations, and co-expression networks of the modules. This study provides insight into the mechanisms underlying brain abnormalities in DS and related disorders.
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Affiliation(s)
- Sihwan Seol
- Department of Life Science, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Republic of Korea
| | - Joonhong Kwon
- Department of Life Science, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Republic of Korea
| | - Hyo Jung Kang
- Department of Life Science, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Republic of Korea,Corresponding author
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Shing N, Walker MC, Chang P. The Role of Aberrant Neural Oscillations in the Hippocampal-Medial Prefrontal Cortex Circuit in Neurodevelopmental and Neurological Disorders. Neurobiol Learn Mem 2022; 195:107683. [PMID: 36174886 DOI: 10.1016/j.nlm.2022.107683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 09/09/2022] [Accepted: 09/20/2022] [Indexed: 11/30/2022]
Abstract
The hippocampus (HPC) and medial prefrontal cortex (mPFC) have well-established roles in cognition, emotion, and sensory processing. In recent years, interests have shifted towards developing a deeper understanding of the mechanisms underlying interactions between the HPC and mPFC in achieving these functions. Considerable research supports the idea that synchronized activity between the HPC and the mPFC is a general mechanism by which brain functions are regulated. In this review, we summarize current knowledge on the hippocampal-medial prefrontal cortex (HPC-mPFC) circuit in normal brain function with a focus on oscillations and highlight several neurodevelopmental and neurological disorders associated with aberrant HPC-mPFC circuitry. We further discuss oscillatory dynamics across the HPC-mPFC circuit as potentially useful biomarkers to assess interventions for neurodevelopmental and neurological disorders. Finally, advancements in brain stimulation, gene therapy and pharmacotherapy are explored as promising therapies for disorders with aberrant HPC-mPFC circuit dynamics.
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Affiliation(s)
- Nathanael Shing
- Department of Clinical and Experimental Epilepsy, Institute of Neurology, University College London, London, WC1N 3BG, UK; Department of Medicine, University of Central Lancashire, Preston, PR17BH, UK
| | - Matthew C Walker
- Department of Clinical and Experimental Epilepsy, Institute of Neurology, University College London, London, WC1N 3BG, UK
| | - Pishan Chang
- Department of Neuroscience, Physiology & Pharmacology, University College London, London, WC1E 6BT.
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6
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Kleschevnikov AM. Enhanced GIRK2 channel signaling in Down syndrome: A feasible role in the development of abnormal nascent neural circuits. Front Genet 2022; 13:1006068. [PMID: 36171878 PMCID: PMC9510977 DOI: 10.3389/fgene.2022.1006068] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 08/24/2022] [Indexed: 11/24/2022] Open
Abstract
The most distinctive feature of Down syndrome (DS) is moderate to severe cognitive impairment. Genetic, molecular, and neuronal mechanisms of this complex DS phenotype are currently under intensive investigation. It is becoming increasingly clear that the abnormalities arise from a combination of initial changes caused by triplication of genes on human chromosome 21 (HSA21) and later compensatory adaptations affecting multiple brain systems. Consequently, relatively mild initial cognitive deficits become pronounced with age. This pattern of changes suggests that one approach to improving cognitive function in DS is to target the earliest critical changes, the prevention of which can change the ‘trajectory’ of the brain development and reduce the destructive effects of the secondary alterations. Here, we review the experimental data on the role of KCNJ6 in DS-specific brain abnormalities, focusing on a putative role of this gene in the development of abnormal neural circuits in the hippocampus of genetic mouse models of DS. It is suggested that the prevention of these early abnormalities with pharmacological or genetic means can ameliorate cognitive impairment in DS.
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Manfredi-Lozano M, Leysen V, Adamo M, Paiva I, Rovera R, Pignat JM, Timzoura FE, Candlish M, Eddarkaoui S, Malone SA, Silva MSB, Trova S, Imbernon M, Decoster L, Cotellessa L, Tena-Sempere M, Claret M, Paoloni-Giacobino A, Plassard D, Paccou E, Vionnet N, Acierno J, Maceski AM, Lutti A, Pfrieger F, Rasika S, Santoni F, Boehm U, Ciofi P, Buée L, Haddjeri N, Boutillier AL, Kuhle J, Messina A, Draganski B, Giacobini P, Pitteloud N, Prevot V. GnRH replacement rescues cognition in Down syndrome. Science 2022; 377:eabq4515. [PMID: 36048943 PMCID: PMC7613827 DOI: 10.1126/science.abq4515] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
At the present time, no viable treatment exists for cognitive and olfactory deficits in Down syndrome (DS). We show in a DS model (Ts65Dn mice) that these progressive nonreproductive neurological symptoms closely parallel a postpubertal decrease in hypothalamic as well as extrahypothalamic expression of a master molecule that controls reproduction-gonadotropin-releasing hormone (GnRH)-and appear related to an imbalance in a microRNA-gene network known to regulate GnRH neuron maturation together with altered hippocampal synaptic transmission. Epigenetic, cellular, chemogenetic, and pharmacological interventions that restore physiological GnRH levels abolish olfactory and cognitive defects in Ts65Dn mice, whereas pulsatile GnRH therapy improves cognition and brain connectivity in adult DS patients. GnRH thus plays a crucial role in olfaction and cognition, and pulsatile GnRH therapy holds promise to improve cognitive deficits in DS.
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Affiliation(s)
- Maria Manfredi-Lozano
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR-S 1172, LabexDistAlz, Lille, France
- Laboratory of Development and Plasticity of the Neuroendocrine Brain, FHU 1000 days for health, EGID, Lille, France
| | - Valerie Leysen
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR-S 1172, LabexDistAlz, Lille, France
- Laboratory of Development and Plasticity of the Neuroendocrine Brain, FHU 1000 days for health, EGID, Lille, France
| | - Michela Adamo
- Department of Endocrinology, Diabetology, and Metabolism, Lausanne University Hospital, 1011 Lausanne, Switzerland
- Faculty of Biology and Medicine, University of Lausanne, Lausanne 1005, Switzerland
| | - Isabel Paiva
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), UMR 7364, Université de Strasbourg-CNRS, Strasbourg, France
| | - Renaud Rovera
- Univ. Lyon, Université Claude Bernard Lyon 1, Inserm, Stem Cell and Brain Research Institute U1208, Bron 69500, France
| | - Jean-Michel Pignat
- Department of Clinical Neurosciences, Neurorehabilitation Unit, University Hospital CHUV, Lausanne, Switzerland
| | - Fatima Ezzahra Timzoura
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR-S 1172, LabexDistAlz, Lille, France
- Laboratory of Development and Plasticity of the Neuroendocrine Brain, FHU 1000 days for health, EGID, Lille, France
| | - Michael Candlish
- Experimental Pharmacology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, 66421, Homburg, Germany
| | - Sabiha Eddarkaoui
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR-S 1172, LabexDistAlz, Lille, France
| | - Samuel A. Malone
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR-S 1172, LabexDistAlz, Lille, France
- Laboratory of Development and Plasticity of the Neuroendocrine Brain, FHU 1000 days for health, EGID, Lille, France
| | - Mauro S. B. Silva
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR-S 1172, LabexDistAlz, Lille, France
- Laboratory of Development and Plasticity of the Neuroendocrine Brain, FHU 1000 days for health, EGID, Lille, France
| | - Sara Trova
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR-S 1172, LabexDistAlz, Lille, France
- Laboratory of Development and Plasticity of the Neuroendocrine Brain, FHU 1000 days for health, EGID, Lille, France
| | - Monica Imbernon
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR-S 1172, LabexDistAlz, Lille, France
- Laboratory of Development and Plasticity of the Neuroendocrine Brain, FHU 1000 days for health, EGID, Lille, France
| | - Laurine Decoster
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR-S 1172, LabexDistAlz, Lille, France
- Laboratory of Development and Plasticity of the Neuroendocrine Brain, FHU 1000 days for health, EGID, Lille, France
| | - Ludovica Cotellessa
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR-S 1172, LabexDistAlz, Lille, France
- Laboratory of Development and Plasticity of the Neuroendocrine Brain, FHU 1000 days for health, EGID, Lille, France
| | - Manuel Tena-Sempere
- Univ. Cordoba, IMIBC/HURS, CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, Cordoba, Spain
| | - Marc Claret
- Neuronal Control of Metabolism Laboratory, Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), 08036 Barcelona, Spain; Centro de Investigación Biomédica en Red (CIBER) de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 08036 Barcelona, Spain
| | - Ariane Paoloni-Giacobino
- Department of Genetic Medicine, University Hospitals of Geneva, 4 rue Gabrielle-Perret-Gentil, 1211, Genève 14, Switzerland
| | - Damien Plassard
- CNRS UMR 7104, INSERM U1258, GenomEast Platform, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, Illkirch, France
| | - Emmanuelle Paccou
- Department of Endocrinology, Diabetology, and Metabolism, Lausanne University Hospital, 1011 Lausanne, Switzerland
| | - Nathalie Vionnet
- Department of Endocrinology, Diabetology, and Metabolism, Lausanne University Hospital, 1011 Lausanne, Switzerland
| | - James Acierno
- Department of Endocrinology, Diabetology, and Metabolism, Lausanne University Hospital, 1011 Lausanne, Switzerland
| | - Aleksandra Maleska Maceski
- Neurologic Clinic and Polyclinic, MS Centre and Research Centre for Clinical Neuroimmunology and Neuroscience Basel; University Hospital Basel, University of Basel, Basel Switzerland
| | - Antoine Lutti
- Laboratory for Research in Neuroimaging LREN, Centre for Research in Neurosciences, Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Switzerland
| | - Frank Pfrieger
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, 67000 Strasbourg, France
| | - S. Rasika
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR-S 1172, LabexDistAlz, Lille, France
- Laboratory of Development and Plasticity of the Neuroendocrine Brain, FHU 1000 days for health, EGID, Lille, France
| | - Federico Santoni
- Faculty of Biology and Medicine, University of Lausanne, Lausanne 1005, Switzerland
| | - Ulrich Boehm
- Experimental Pharmacology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, 66421, Homburg, Germany
| | - Philippe Ciofi
- Univ. Bordeaux, Inserm, U1215, Neurocentre Magendie, Bordeaux, France
| | - Luc Buée
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR-S 1172, LabexDistAlz, Lille, France
| | - Nasser Haddjeri
- Univ. Lyon, Université Claude Bernard Lyon 1, Inserm, Stem Cell and Brain Research Institute U1208, Bron 69500, France
| | - Anne-Laurence Boutillier
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), UMR 7364, Université de Strasbourg-CNRS, Strasbourg, France
| | - Jens Kuhle
- Neurologic Clinic and Polyclinic, MS Centre and Research Centre for Clinical Neuroimmunology and Neuroscience Basel; University Hospital Basel, University of Basel, Basel Switzerland
| | - Andrea Messina
- Department of Endocrinology, Diabetology, and Metabolism, Lausanne University Hospital, 1011 Lausanne, Switzerland
- Faculty of Biology and Medicine, University of Lausanne, Lausanne 1005, Switzerland
| | - Bogdan Draganski
- Laboratory for Research in Neuroimaging LREN, Centre for Research in Neurosciences, Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Switzerland
- Neurology Department, Max-Planck-Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Paolo Giacobini
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR-S 1172, LabexDistAlz, Lille, France
- Laboratory of Development and Plasticity of the Neuroendocrine Brain, FHU 1000 days for health, EGID, Lille, France
| | - Nelly Pitteloud
- Department of Endocrinology, Diabetology, and Metabolism, Lausanne University Hospital, 1011 Lausanne, Switzerland
- Faculty of Biology and Medicine, University of Lausanne, Lausanne 1005, Switzerland
| | - Vincent Prevot
- Univ. Lille, Inserm, CHU Lille, Lille Neuroscience & Cognition, UMR-S 1172, LabexDistAlz, Lille, France
- Laboratory of Development and Plasticity of the Neuroendocrine Brain, FHU 1000 days for health, EGID, Lille, France
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8
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Alemany-González M, Vilademunt M, Gener T, Puig MV. Postnatal environmental enrichment enhances memory through distinct neural mechanisms in healthy and trisomic female mice. Neurobiol Dis 2022; 173:105841. [PMID: 35988873 DOI: 10.1016/j.nbd.2022.105841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 08/12/2022] [Accepted: 08/15/2022] [Indexed: 10/15/2022] Open
Abstract
Stimulating lifestyles have powerful effects on cognitive abilities, especially when they are experienced early in life. Cognitive therapies are widely used to improve cognitive impairment due to intellectual disability, aging, and neurodegeneration, however the underlying neural mechanisms are poorly understood. We investigated the neural correlates of memory amelioration produced by postnatal environmental enrichment (EE) in diploid mice and the Ts65Dn mouse model of Down syndrome (trisomy 21). We recorded neural activities in brain structures key for memory processing, the hippocampus and the prefrontal cortex, during rest, sleep and memory performance in mice reared in non-enriched or enriched environments. Enriched wild-type animals exhibited enhanced neural synchrony in the hippocampus across different brain states (increased gamma oscillations, theta-gamma coupling, sleep ripples). Trisomic females showed increased theta and gamma rhythms in the hippocampus and prefrontal cortex across different brain states along with enlarged ripples and disrupted circuit gamma signals that were associated with memory deficits. These pathological activities were attenuated in their trisomic EE-reared peers. Our results suggest distinct neural mechanisms for the generation and rescue of healthy and pathological brain synchrony, respectively, by EE and put forward hippocampal-prefrontal hypersynchrony and miscommunication as major targets underlying the beneficial effects of EE in intellectual disability.
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Affiliation(s)
- Maria Alemany-González
- Integrative Pharmacology and Systems Neuroscience, Hospital del Mar Medical Research Institute, Barcelona Biomedical Research Park, 08003 Barcelona, Spain
| | - Marta Vilademunt
- Integrative Pharmacology and Systems Neuroscience, Hospital del Mar Medical Research Institute, Barcelona Biomedical Research Park, 08003 Barcelona, Spain
| | - Thomas Gener
- Integrative Pharmacology and Systems Neuroscience, Hospital del Mar Medical Research Institute, Barcelona Biomedical Research Park, 08003 Barcelona, Spain; Catalan Institute of Nanoscience and Nanotechnology (ICN2), the Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, 08193 Barcelona, Spain; Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - M Victoria Puig
- Integrative Pharmacology and Systems Neuroscience, Hospital del Mar Medical Research Institute, Barcelona Biomedical Research Park, 08003 Barcelona, Spain; Catalan Institute of Nanoscience and Nanotechnology (ICN2), the Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, 08193 Barcelona, Spain; Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
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9
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Sibarani CR, Walter LM, Davey MJ, Nixon GM, Horne RSC. Sleep-disordered breathing and sleep macro- and micro-architecture in children with Down syndrome. Pediatr Res 2022; 91:1248-1256. [PMID: 34230620 DOI: 10.1038/s41390-021-01642-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 06/16/2021] [Accepted: 06/21/2021] [Indexed: 01/07/2023]
Abstract
BACKGROUND Children with Down syndrome (DS) are at increased risk of sleep-disordered breathing (SDB), which is associated with intermittent hypoxia and sleep disruption affecting daytime functioning. We aimed to compare the impact of SDB on sleep quality in children with DS compared to typically developing (TD) children with and without SDB. METHODS Children with DS and SDB (n = 44) were age- and sex-matched with TD children without SDB (TD-) and also for SDB severity with TD children with SDB (TD+). Children underwent overnight polysomnography with sleep macro- and micro-architecture assessed using electroencephalogram (EEG) spectral analysis, including slow-wave activity (SWA, an indicator of sleep propensity). RESULTS Children with DS had greater hypoxic exposure, more respiratory events during REM sleep, higher total, delta, sigma, and beta EEG power in REM than TD+ children, despite the same overall frequency of obstructive events. Compared to TD- children, they also had more wake after sleep-onset and lower sigma power in N2 and N3. The DS group had reduced SWA, indicating reduced sleep drive, compared to both TD groups. CONCLUSIONS Our findings suggest that SDB has a greater impact on sleep quality in children with DS compared to TD children. IMPACT SDB in children with DS exacerbates disruption of sleep quality, compared to TD children. The prevalence of SDB is very high in children with DS; however, studies on the effects of SDB on sleep quality are limited in this population. Our findings suggest that SDB has a greater impact on sleep quality in children with DS compared to TD children, and should be screened for and treated as soon as possible.
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Affiliation(s)
- Christy R Sibarani
- Department of Paediatrics and The Ritchie Centre, Monash University, Melbourne, VIC, Australia
| | - Lisa M Walter
- Department of Paediatrics and The Ritchie Centre, Monash University, Melbourne, VIC, Australia
| | - Margot J Davey
- Department of Paediatrics and The Ritchie Centre, Monash University, Melbourne, VIC, Australia.,Melbourne Children's Sleep Centre, Monash Children's Hospital, Melbourne, VIC, Australia
| | - Gillian M Nixon
- Department of Paediatrics and The Ritchie Centre, Monash University, Melbourne, VIC, Australia.,Melbourne Children's Sleep Centre, Monash Children's Hospital, Melbourne, VIC, Australia
| | - Rosemary S C Horne
- Department of Paediatrics and The Ritchie Centre, Monash University, Melbourne, VIC, Australia.
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10
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Brault V, Nguyen TL, Flores-Gutiérrez J, Iacono G, Birling MC, Lalanne V, Meziane H, Manousopoulou A, Pavlovic G, Lindner L, Selloum M, Sorg T, Yu E, Garbis SD, Hérault Y. Dyrk1a gene dosage in glutamatergic neurons has key effects in cognitive deficits observed in mouse models of MRD7 and Down syndrome. PLoS Genet 2021; 17:e1009777. [PMID: 34587162 PMCID: PMC8480849 DOI: 10.1371/journal.pgen.1009777] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 08/16/2021] [Indexed: 12/03/2022] Open
Abstract
Perturbation of the excitation/inhibition (E/I) balance leads to neurodevelopmental diseases including to autism spectrum disorders, intellectual disability, and epilepsy. Loss-of-function mutations in the DYRK1A gene, located on human chromosome 21 (Hsa21,) lead to an intellectual disability syndrome associated with microcephaly, epilepsy, and autistic troubles. Overexpression of DYRK1A, on the other hand, has been linked with learning and memory defects observed in people with Down syndrome (DS). Dyrk1a is expressed in both glutamatergic and GABAergic neurons, but its impact on each neuronal population has not yet been elucidated. Here we investigated the impact of Dyrk1a gene copy number variation in glutamatergic neurons using a conditional knockout allele of Dyrk1a crossed with the Tg(Camk2-Cre)4Gsc transgenic mouse. We explored this genetic modification in homozygotes, heterozygotes and combined with the Dp(16Lipi-Zbtb21)1Yey trisomic mouse model to unravel the consequence of Dyrk1a dosage from 0 to 3, to understand its role in normal physiology, and in MRD7 and DS. Overall, Dyrk1a dosage in postnatal glutamatergic neurons did not impact locomotor activity, working memory or epileptic susceptibility, but revealed that Dyrk1a is involved in long-term explicit memory. Molecular analyses pointed at a deregulation of transcriptional activity through immediate early genes and a role of DYRK1A at the glutamatergic post-synapse by deregulating and interacting with key post-synaptic proteins implicated in mechanism leading to long-term enhanced synaptic plasticity. Altogether, our work gives important information to understand the action of DYRK1A inhibitors and have a better therapeutic approach. The Dual Specificity Tyrosine Phosphorylation Regulated Kinase 1A, DYRK1A, drives cognitive alterations with increased dose in Down syndrome (DS) or with reduced dose in DYRK1A-related intellectual disability syndromes (ORPHA:268261; ORPHA:464311) also known as mental retardation, autosomal dominant disease 7 (MRD7; OMIM #614104). Here we report that specific and complete loss of Dyrk1a in glutamatergic neurons induced a range of specific cognitive phenotypes and alter the expression of genes involved in neurotransmission in the hippocampus. We further explored the consequences of Dyrk1a dosage in glutamatergic neurons on the cognitive phenotypes observed respectively in MRD7 and DS mouse models and we found specific roles in long-term explicit memory with no impact on motor activity, short-term working memory, and susceptibility to epilepsy. Then we demonstrated that DYRK1A is a component of the glutamatergic post-synapse and interacts with several component such as NR2B and PSD95. Altogether our work describes a new role of DYRK1A at the glutamatergic synapse that must be considered to understand the consequence of treatment targeting DYRK1A in disease.
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Affiliation(s)
- Véronique Brault
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, IGBMC, Illkirch, France
| | - Thu Lan Nguyen
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, IGBMC, Illkirch, France
| | - Javier Flores-Gutiérrez
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, IGBMC, Illkirch, France
| | - Giovanni Iacono
- Department of Molecular Biology, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, the Netherlands
| | - Marie-Christine Birling
- Université de Strasbourg, CNRS, INSERM, CELPHEDIA, PHENOMIN, Institut Clinique de la Souris, Illkirch, France
| | - Valérie Lalanne
- Université de Strasbourg, CNRS, INSERM, CELPHEDIA, PHENOMIN, Institut Clinique de la Souris, Illkirch, France
| | - Hamid Meziane
- Université de Strasbourg, CNRS, INSERM, CELPHEDIA, PHENOMIN, Institut Clinique de la Souris, Illkirch, France
| | - Antigoni Manousopoulou
- Institute for Life Sciences, University of Southampton, School of Medicine, Southampton, United Kingdom
| | - Guillaume Pavlovic
- Université de Strasbourg, CNRS, INSERM, CELPHEDIA, PHENOMIN, Institut Clinique de la Souris, Illkirch, France
| | - Loïc Lindner
- Université de Strasbourg, CNRS, INSERM, CELPHEDIA, PHENOMIN, Institut Clinique de la Souris, Illkirch, France
| | - Mohammed Selloum
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, IGBMC, Illkirch, France
| | - Tania Sorg
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, IGBMC, Illkirch, France
| | - Eugene Yu
- The Children’s Guild Foundation Down Syndrome Research Program, Genetics and Genomics Program and Department of Cancer Genetics and Genomics, Roswell Park Comprehensive Cancer Center, Buffalo, New York, United States of America
- Genetics, Genomics and Bioinformatics Program, State University of New York At Buffalo, Buffalo, New York, United States of America
| | - Spiros D. Garbis
- Institute for Life Sciences, University of Southampton, School of Medicine, Southampton, United Kingdom
| | - Yann Hérault
- Université de Strasbourg, CNRS, INSERM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, IGBMC, Illkirch, France
- Université de Strasbourg, CNRS, INSERM, CELPHEDIA, PHENOMIN, Institut Clinique de la Souris, Illkirch, France
- * E-mail:
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11
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Pannuzzo M. Beta-amyloid pore linked to controlled calcium influx into the cell: A new paradigm for Alzheimer's Disease. Alzheimers Dement 2021; 18:191-196. [PMID: 34051062 PMCID: PMC9290490 DOI: 10.1002/alz.12373] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 01/20/2021] [Accepted: 04/16/2021] [Indexed: 11/28/2022]
Abstract
Despite tremendous worldwide efforts, clinical trials assessing Alzheimer's disease (AD)‐related therapeutics have been relentlessly unsuccessful. Hence, there is an urgent need to challenge old hypotheses with novel paradigms. An emerging concept is that the amyloid‐beta (Aβ) peptide, which was until recently deemed a major player in the cause of AD, may instead modulate synaptic plasticity and protect against excitotoxicity. The link between Aβ‐mediated synaptic plasticity and Aβ trafficking is central for understanding AD pathogenesis and remains a perplexing relationship. The crossover between Aβ pathological and physiological roles is subtle and remains controversial. Based on existing literature, as a signaling molecule, Aβ is proposed to modulate its own turnover and synaptic plasticity through what is currently believed to be the cause of AD: the transient formation of pore‐like oligomers. A change of perspective regarding how Aβ pores exert a protective function will unavoidably revolutionize the entire field of anti‐amyloid drug development.
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Affiliation(s)
- Martina Pannuzzo
- Laboratory of Nanotechnology for Precision Medicine, Fondazione Istituto Italiano di Tecnologia, Genoa, Italy
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12
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Côté V, Lalancette È, Knoth IS, Côté L, Agbogba K, Vannasing P, Major P, Barlaam F, Michaud J, Lippé S. Distinct patterns of repetition suppression in Fragile X syndrome, down syndrome, tuberous sclerosis complex and mutations in SYNGAP1. Brain Res 2020; 1751:147205. [PMID: 33189692 DOI: 10.1016/j.brainres.2020.147205] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 10/31/2020] [Accepted: 11/08/2020] [Indexed: 12/29/2022]
Abstract
Sensory processing is the gateway to information processing and more complex processes such as learning. Alterations in sensory processing is a common phenotype of many genetic syndromes associated with intellectual disability (ID). It is currently unknown whether sensory processing alterations converge or diverge on brain responses between syndromes. Here, we compare for the first time four genetic conditions with ID using the same basic sensory learning paradigm. One hundred and five participants, aged between 3 and 30 years old, composing four clinical ID groups and one control group, were recruited: Fragile X syndrome (FXS; n = 14), tuberous sclerosis complex (TSC; n = 9), Down syndrome (DS; n = 19), SYNGAP1 mutations (n = 8) and Neurotypical controls (NT; n = 55)). All groups included female and male participants. Brain responses were recorded using electroencephalography (EEG) during an audio-visual task that involved three repetitions of the pronunciation of the phoneme /a/. Event Related Potentials (ERP) were used to: 1) compare peak-to-peak amplitudes between groups, 2) evaluate the presence of repetition suppression within each group and 3) compare the relative repetition suppression between groups. Our results revealed larger overall amplitudes in FXS. A repetition suppression (RS) pattern was found in the NT group, FXS and DS, suggesting spared repetition suppression in a multimodal task in these two ID syndromes. Interestingly, FXS presented a stronger RS on one peak-to-peak value in comparison with the NT. The results of our study reveal the distinctiveness of ERP and RS brain responses in ID syndromes. Further studies should be conducted to understand the molecular mechanisms involved in these patterns of responses.
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Affiliation(s)
- Valérie Côté
- Psychology Departement, Université de Montréal, Pavillon Marie-Victorin, 90, Avenue Vincent d'Indy, Montréal, QC H2V 2S9, Canada; NED Laboratory, Office 5.2.43, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC H3T 1C5, Canada; Research Center UHC Sainte-Justine, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC H3T 1C5, Canada.
| | - Ève Lalancette
- Psychology Departement, Université de Montréal, Pavillon Marie-Victorin, 90, Avenue Vincent d'Indy, Montréal, QC H2V 2S9, Canada; NED Laboratory, Office 5.2.43, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC H3T 1C5, Canada; Research Center UHC Sainte-Justine, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC H3T 1C5, Canada
| | - Inga S Knoth
- NED Laboratory, Office 5.2.43, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC H3T 1C5, Canada; Research Center UHC Sainte-Justine, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC H3T 1C5, Canada
| | - Lucie Côté
- Neurology Program, CHU Sainte-Justine, Montréal, 3175 Chemin de la Côte-Sainte-Catherine, QC H3T 1C5, Canada.
| | - Kristian Agbogba
- NED Laboratory, Office 5.2.43, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC H3T 1C5, Canada; Research Center UHC Sainte-Justine, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC H3T 1C5, Canada.
| | - Phetsamone Vannasing
- Research Center UHC Sainte-Justine, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC H3T 1C5, Canada.
| | - Philippe Major
- Neurology Program, CHU Sainte-Justine, Montréal, 3175 Chemin de la Côte-Sainte-Catherine, QC H3T 1C5, Canada; Research Center UHC Sainte-Justine, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC H3T 1C5, Canada.
| | - Fanny Barlaam
- NED Laboratory, Office 5.2.43, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC H3T 1C5, Canada; Research Center UHC Sainte-Justine, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC H3T 1C5, Canada
| | - Jacques Michaud
- Research Center UHC Sainte-Justine, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC H3T 1C5, Canada.
| | - Sarah Lippé
- Psychology Departement, Université de Montréal, Pavillon Marie-Victorin, 90, Avenue Vincent d'Indy, Montréal, QC H2V 2S9, Canada; NED Laboratory, Office 5.2.43, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC H3T 1C5, Canada; Research Center UHC Sainte-Justine, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC H3T 1C5, Canada.
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Abstract
Culture is part of an extensive series of feedback loops, which involve multiple organismic levels including social contexts, cognitive mediations, neural processes, and behavior. Recent studies in neuroscience show that culturally contingent social processes shape some neural pathways. Studying the influence of cultural context on neural processes may yield new insights into psychiatric disorders. New methodologies in the neurosciences offer innovative ways to assess the impact of culture on mental health and illness. However, implementing these methodologies raises important theoretical and ethical concerns, which must be resolved to address patient individuality and the complexity of cultural diversity. This article discusses cultural context as a major influence on (and consequence of) human neural plasticity and advocates a culture-brain-behavior (CBB) interaction model for conceptualizing the relationship between culture, brain, and psychiatric disorders. Recommendations are made for integrating neuroscientific techniques into transcultural psychiatric research by taking a systems approach to evaluating disorders.
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14
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Chaves JCS, Machado FT, Almeida MF, Bacovsky TB, Ferrari MFR. microRNAs expression correlates with levels of APP, DYRK1A, hyperphosphorylated Tau and BDNF in the hippocampus of a mouse model for Down syndrome during ageing. Neurosci Lett 2020; 714:134541. [PMID: 31605772 DOI: 10.1016/j.neulet.2019.134541] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Revised: 08/28/2019] [Accepted: 10/08/2019] [Indexed: 01/08/2023]
Abstract
Down syndrome (DS) patients are more susceptible to Alzheimer's disease (AD) due to the presence of three copies of genes on chromosome 21 such as DYRK1A, which encodes a broad acting kinase, and APP (amyloid precursor protein), leading to formation of amyloid beta (Aβ) peptide and hyperphosphorylation of Tau. In this study, we investigated the association among miRNAs miR-17, -20a, -101, -106b, -199b, -26a, 26b and some of their target mRNAs such as APP, DYRK1A and BDNF, as well as the levels of hyperphosphorylated Tau in the hippocampus of a 2 and 5 months old mice model of trisomy 21 (Ts65Dn). Results indicated that increased APP expression in the hippocampus of 5 months old DS mice might be correlated with decrease in miR-17, -20a, -101 and -106b. Whereas at 2 months of age normal levels of APP expression in the hippocampus was correlated with increased levels of miR-17, -101 and -106b in DS mice. DYRK1A mRNA also increased in the hippocampus of 5 months old DS mice and it is associated with decreased levels of miR-199b. Increased levels of DYRK1A in 5-month old mice are associated with increased phosphorylation of Tau at Thr212 residue but not at Ser199-202. Tau pathology is accompanied by decreased expression of BDNF and increased miR-26a/b in mice of 5 months of age. Taken together, data indicate that miR-17, -20a, -26a/b, -101, -106b and -199b might be interesting targets to mitigate Tau and Aβ pathology in DS.
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Affiliation(s)
- Juliana C S Chaves
- Departamento de Genetica e Biologia Evolutiva, Instituto de Biociencias, Universidade de Sao Paulo, Sao Paulo, SP, Brazil
| | - Felippe T Machado
- Departamento de Genetica e Biologia Evolutiva, Instituto de Biociencias, Universidade de Sao Paulo, Sao Paulo, SP, Brazil
| | - Michael F Almeida
- Departamento de Genetica e Biologia Evolutiva, Instituto de Biociencias, Universidade de Sao Paulo, Sao Paulo, SP, Brazil
| | - Tatiana B Bacovsky
- Departamento de Genetica e Biologia Evolutiva, Instituto de Biociencias, Universidade de Sao Paulo, Sao Paulo, SP, Brazil
| | - Merari F R Ferrari
- Departamento de Genetica e Biologia Evolutiva, Instituto de Biociencias, Universidade de Sao Paulo, Sao Paulo, SP, Brazil.
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15
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Lauterborn JC, Schultz MN, Le AA, Amani M, Friedman AE, Leach PT, Gall CM, Lynch GS, Crawley JN. Spaced training improves learning in Ts65Dn and Ube3a mouse models of intellectual disabilities. Transl Psychiatry 2019; 9:166. [PMID: 31182707 PMCID: PMC6557858 DOI: 10.1038/s41398-019-0495-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 03/14/2019] [Accepted: 03/23/2019] [Indexed: 12/29/2022] Open
Abstract
Benefits of distributed learning strategies have been extensively described in the human literature, but minimally investigated in intellectual disability syndromes. We tested the hypothesis that training trials spaced apart in time could improve learning in two distinct genetic mouse models of neurodevelopmental disorders characterized by intellectual impairments. As compared to training with massed trials, spaced training significantly improved learning in both the Ts65Dn trisomy mouse model of Down syndrome and the maternally inherited Ube3a mutant mouse model of Angelman syndrome. Spacing the training trials at 1 h intervals accelerated acquisition of three cognitive tasks by Ts65Dn mice: (1) object location memory, (2) novel object recognition, (3) water maze spatial learning. Further, (4) spaced training improved water maze spatial learning by Ube3a mice. In contrast, (5) cerebellar-mediated rotarod motor learning was not improved by spaced training. Corroborations in three assays, conducted in two model systems, replicated within and across two laboratories, confirm the strength of the findings. Our results indicate strong translational relevance of a behavioral intervention strategy for improving the standard of care in treating the learning difficulties that are characteristic and clinically intractable features of many neurodevelopmental disorders.
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Affiliation(s)
- J C Lauterborn
- Department of Anatomy & Neurobiology, School of Medicine, University of California Irvine, Irvine, CA, 92697, USA
| | - M N Schultz
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA 95817, USA
| | - A A Le
- Department of Anatomy & Neurobiology, School of Medicine, University of California Irvine, Irvine, CA, 92697, USA
| | - M Amani
- Department of Psychiatry and Human Behavior, School of Medicine, University of California Irvine, Irvine, CA, 92697, USA
- Department of Physiology, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran
| | - A E Friedman
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA 95817, USA
- Harvard University, Cambridge, MA, USA
| | - P T Leach
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA 95817, USA
- Biogen Inc., Cambridge, MA, USA
| | - C M Gall
- Department of Anatomy & Neurobiology, School of Medicine, University of California Irvine, Irvine, CA, 92697, USA
| | - G S Lynch
- Department of Anatomy & Neurobiology, School of Medicine, University of California Irvine, Irvine, CA, 92697, USA
- Department of Psychiatry and Human Behavior, School of Medicine, University of California Irvine, Irvine, CA, 92697, USA
| | - J N Crawley
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA 95817, USA.
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16
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Down syndrome: Neurobiological alterations and therapeutic targets. Neurosci Biobehav Rev 2019; 98:234-255. [DOI: 10.1016/j.neubiorev.2019.01.001] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 01/02/2019] [Accepted: 01/02/2019] [Indexed: 12/12/2022]
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17
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Zhao X, Bhattacharyya A. Human Models Are Needed for Studying Human Neurodevelopmental Disorders. Am J Hum Genet 2018; 103:829-857. [PMID: 30526865 DOI: 10.1016/j.ajhg.2018.10.009] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 10/09/2018] [Indexed: 12/19/2022] Open
Abstract
The analysis of animal models of neurological disease has been instrumental in furthering our understanding of neurodevelopment and brain diseases. However, animal models are limited in revealing some of the most fundamental aspects of development, genetics, pathology, and disease mechanisms that are unique to humans. These shortcomings are exaggerated in disorders that affect the brain, where the most significant differences between humans and animal models exist, and could underscore failures in targeted therapeutic interventions in affected individuals. Human pluripotent stem cells have emerged as a much-needed model system for investigating human-specific biology and disease mechanisms. However, questions remain regarding whether these cell-culture-based models are sufficient or even necessary. In this review, we summarize human-specific features of neurodevelopment and the most common neurodevelopmental disorders, present discrepancies between animal models and human diseases, demonstrate how human stem cell models can provide meaningful information, and discuss the challenges that exist in our pursuit to understand distinctively human aspects of neurodevelopment and brain disease. This information argues for a more thoughtful approach to disease modeling through consideration of the valuable features and limitations of each model system, be they human or animal, to mimic disease characteristics.
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Affiliation(s)
- Xinyu Zhao
- Waisman Center, School of Medicine and Public Health, University of Wisconsin-Madison, Madison WI 53705, USA; Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin-Madison, Madison WI 53705, USA.
| | - Anita Bhattacharyya
- Waisman Center, School of Medicine and Public Health, University of Wisconsin-Madison, Madison WI 53705, USA; Department of Cell and Regenerative Biology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison WI 53705, USA.
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18
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Gómez de Salazar M, Grau C, Ciruela F, Altafaj X. Phosphoproteomic Alterations of Ionotropic Glutamate Receptors in the Hippocampus of the Ts65Dn Mouse Model of Down Syndrome. Front Mol Neurosci 2018; 11:226. [PMID: 30140203 PMCID: PMC6095006 DOI: 10.3389/fnmol.2018.00226] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 06/11/2018] [Indexed: 11/25/2022] Open
Abstract
Down syndrome (DS), the main genetic cause of intellectual disability, is associated with an imbalance of excitatory/inhibitory neurotransmitter systems. The phenotypic assessment and pharmacotherapy interventions in DS murine models strongly pointed out glutamatergic neurotransmission alterations (specially affecting ionotropic glutamate receptors [iGluRs]) that might contribute to DS pathophysiology, which is in agreement with DS condition. iGluRs play a critical role in fast-mediated excitatory transmission, a process underlying synaptic plasticity. Neuronal plasticity is biochemically modulated by post-translational modifications, allowing rapid and reversible adaptation of synaptic strength. Among these modifications, phosphorylation/dephosphorylation processes strongly dictate iGluR protein–protein interactions, cell surface trafficking, and subsynaptic mobility. Hence, we hypothesized that dysregulation of phosphorylation/dephosphorylation balance might affect neuronal function, which in turn could contribute to the glutamatergic neurotransmitter alterations observed in DS. To address this point, we biochemically purified subsynaptic hippocampal fractions from adult Ts65Dn mice, a trisomic mouse model recapitulating DS phenotypic alterations. Proteomic analysis showed significant alterations of the molecular composition of subsynaptic compartments of hippocampal trisomic neurons. Further, we characterized iGluR phosphopattern in the hippocampal glutamatergic synapse of trisomic mice. Phosphoenrichment-coupled mass spectrometry analysis revealed specific subsynaptic- and trisomy-associated iGluR phosphorylation signature, concomitant with differential subsynaptic kinase and phosphatase composition of Ts65Dn hippocampal subsynaptic compartments. Furthermore, biochemical data were used to build up a genotype-kinome-iGluR phosphopattern matrix in the different subsynaptic compartments. Overall, our results provide a precise profile of iGluR phosphopattern alterations in the glutamatergic synapse of the Ts65Dn mouse model and support their contribution to DS-associated synaptopathy. The alteration of iGluR phosphoresidues in Ts65Dn hippocampi, together with the kinase/phosphatase signature, identifies potential novel therapeutic targets for the treatment of glutamatergic dysfunctions in DS.
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Affiliation(s)
- Macarena Gómez de Salazar
- Neuropharmacology Unit, Bellvitge Biomedical Research Institute (IDIBELL)-University of Barcelona, Barcelona, Spain
| | - Cristina Grau
- Neuropharmacology Unit, Bellvitge Biomedical Research Institute (IDIBELL)-University of Barcelona, Barcelona, Spain
| | - Francisco Ciruela
- Neuropharmacology Unit, Bellvitge Biomedical Research Institute (IDIBELL)-University of Barcelona, Barcelona, Spain
| | - Xavier Altafaj
- Neuropharmacology Unit, Bellvitge Biomedical Research Institute (IDIBELL)-University of Barcelona, Barcelona, Spain
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19
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Leach PT, Crawley JN. Touchscreen learning deficits in Ube3a, Ts65Dn and Mecp2 mouse models of neurodevelopmental disorders with intellectual disabilities. GENES, BRAIN, AND BEHAVIOR 2018; 17:e12452. [PMID: 29266714 PMCID: PMC6013336 DOI: 10.1111/gbb.12452] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 11/29/2017] [Accepted: 12/16/2017] [Indexed: 12/25/2022]
Abstract
Mutant mouse models of neurodevelopmental disorders with intellectual disabilities provide useful translational research tools, especially in cases where robust cognitive deficits are reproducibly detected. However, motor, sensory and/or health issues consequent to the mutation may introduce artifacts that preclude testing in some standard cognitive assays. Touchscreen learning and memory tasks in small operant chambers have the potential to circumvent these confounds. Here we use touchscreen visual discrimination learning to evaluate performance in the maternally derived Ube3a mouse model of Angelman syndrome, the Ts65Dn trisomy mouse model of Down syndrome, and the Mecp2Bird mouse model of Rett syndrome. Significant deficits in acquisition of a 2-choice visual discrimination task were detected in both Ube3a and Ts65Dn mice. Procedural control measures showed no genotype differences during pretraining phases or during acquisition. Mecp2 males did not survive long enough for touchscreen training, consistent with previous reports. Most Mecp2 females failed on pretraining criteria. Significant impairments on Morris water maze spatial learning were detected in both Ube3a and Ts65Dn, replicating previous findings. Abnormalities on rotarod in Ube3a, and on open field in Ts65Dn, replicating previous findings, may have contributed to the observed acquisition deficits and swim speed abnormalities during water maze performance. In contrast, these motor phenotypes do not appear to have affected touchscreen procedural abilities during pretraining or visual discrimination training. Our findings of slower touchscreen learning in 2 mouse models of neurodevelopmental disorders with intellectual disabilities indicate that operant tasks offer promising outcome measures for the preclinical discovery of effective pharmacological therapeutics.
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Affiliation(s)
- P T Leach
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, California
| | - J N Crawley
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, California
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20
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Kazim SF, Blanchard J, Bianchi R, Iqbal K. Early neurotrophic pharmacotherapy rescues developmental delay and Alzheimer's-like memory deficits in the Ts65Dn mouse model of Down syndrome. Sci Rep 2017; 7:45561. [PMID: 28368015 PMCID: PMC5377379 DOI: 10.1038/srep45561] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 02/27/2017] [Indexed: 12/21/2022] Open
Abstract
Down syndrome (DS), caused by trisomy 21, is the most common genetic cause of intellectual disability and is associated with a greatly increased risk of early-onset Alzheimer’s disease (AD). The Ts65Dn mouse model of DS exhibits several key features of the disease including developmental delay and AD-like cognitive impairment. Accumulating evidence suggests that impairments in early brain development caused by trisomy 21 contribute significantly to memory deficits in adult life in DS. Prenatal genetic testing to diagnose DS in utero, provides the novel opportunity to initiate early pharmacological treatment to target this critical period of brain development. Here, we report that prenatal to early postnatal treatment with a ciliary neurotrophic factor (CNTF) small-molecule peptide mimetic, Peptide 021 (P021), rescued developmental delay in pups and AD-like hippocampus-dependent memory impairments in adult life in Ts65Dn mice. Furthermore, this treatment prevented pre-synaptic protein deficit, decreased glycogen synthase kinase-3beta (GSK3β) activity, and increased levels of synaptic plasticity markers including brain derived neurotrophic factor (BNDF) and phosphorylated CREB, both in young (3-week-old) and adult (~ 7-month-old) Ts65Dn mice. These findings provide novel evidence that providing neurotrophic support during early brain development can prevent developmental delay and AD-like memory impairments in a DS mouse model.
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Affiliation(s)
- Syed Faraz Kazim
- Department of Neurochemistry, and SUNY Downstate/NYSIBR Center for Developmental Neuroscience, New York State Institute for Basic Research (NYSIBR), Staten Island, NY 10314, USA.,The 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 11203, USA.,Graduate Program in Neural and Behavioral Science, SUNY Downstate Medical Center, Brooklyn, NY 11203, USA
| | - Julie Blanchard
- Department of Neurochemistry, and SUNY Downstate/NYSIBR Center for Developmental Neuroscience, New York State Institute for Basic Research (NYSIBR), Staten Island, NY 10314, USA
| | - Riccardo Bianchi
- The 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 11203, 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 10314, USA
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21
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De Giorgio A. The roles of motor activity and environmental enrichment in intellectual disability. Somatosens Mot Res 2017; 34:34-43. [PMID: 28140743 DOI: 10.1080/08990220.2016.1278204] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In people with intellectual disabilities, an enriched environment can stimulate the acquisition of motor skills and could partially repair neuronal impairment thanks to exploration and motor activity. A deficit in environmental and motor stimulation leads to low scores in intelligence tests and can cause serious motor skill problems. Although studies in humans do not give much evidence for explaining basic mechanisms of intellectual disability and for highlighting improvements due to enriched environmental stimulation, animal models have been valuable in the investigation of these conditions. Here, we discuss the role of environmental enrichment in four intellectual disabilities: Foetal Alcohol Spectrum Disorder (FASD), Down, Rett, and Fragile X syndromes.
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Affiliation(s)
- Andrea De Giorgio
- a Department of Psychology , eCampus University , Novedrate , Italy.,b Department of Psychology , Universita Cattolica del Sacro Cuore , Milano , Italy
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22
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Lepeta K, Lourenco MV, Schweitzer BC, Martino Adami PV, Banerjee P, Catuara-Solarz S, de La Fuente Revenga M, Guillem AM, Haidar M, Ijomone OM, Nadorp B, Qi L, Perera ND, Refsgaard LK, Reid KM, Sabbar M, Sahoo A, Schaefer N, Sheean RK, Suska A, Verma R, Vicidomini C, Wright D, Zhang XD, Seidenbecher C. Synaptopathies: synaptic dysfunction in neurological disorders - A review from students to students. J Neurochem 2016; 138:785-805. [PMID: 27333343 PMCID: PMC5095804 DOI: 10.1111/jnc.13713] [Citation(s) in RCA: 216] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 06/03/2016] [Accepted: 06/06/2016] [Indexed: 12/12/2022]
Abstract
Synapses are essential components of neurons and allow information to travel coordinately throughout the nervous system to adjust behavior to environmental stimuli and to control body functions, memories, and emotions. Thus, optimal synaptic communication is required for proper brain physiology, and slight perturbations of synapse function can lead to brain disorders. In fact, increasing evidence has demonstrated the relevance of synapse dysfunction as a major determinant of many neurological diseases. This notion has led to the concept of synaptopathies as brain diseases with synapse defects as shared pathogenic features. In this review, which was initiated at the 13th International Society for Neurochemistry Advanced School, we discuss basic concepts of synapse structure and function, and provide a critical view of how aberrant synapse physiology may contribute to neurodevelopmental disorders (autism, Down syndrome, startle disease, and epilepsy) as well as neurodegenerative disorders (Alzheimer and Parkinson disease). We finally discuss the appropriateness and potential implications of gathering synapse diseases under a single term. Understanding common causes and intrinsic differences in disease-associated synaptic dysfunction could offer novel clues toward synapse-based therapeutic intervention for neurological and neuropsychiatric disorders. In this Review, which was initiated at the 13th International Society for Neurochemistry (ISN) Advanced School, we discuss basic concepts of synapse structure and function, and provide a critical view of how aberrant synapse physiology may contribute to neurodevelopmental (autism, Down syndrome, startle disease, and epilepsy) as well as neurodegenerative disorders (Alzheimer's and Parkinson's diseases), gathered together under the term of synaptopathies. Read the Editorial Highlight for this article on page 783.
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Affiliation(s)
- Katarzyna Lepeta
- Department of Molecular and Cellular Neurobiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Mychael V Lourenco
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Barbara C Schweitzer
- Department for Neurochemistry and Molecular Biology, Leibniz Institute for Neurobiology Magdeburg, Magdeburg, Germany
| | - Pamela V Martino Adami
- Laboratory of Amyloidosis and Neurodegeneration, Fundación Instituto Leloir-IIBBA-CONICET, Buenos Aires, Argentina
| | - Priyanjalee Banerjee
- Department of Biochemistry, Institute of Post Graduate Medical Education & Research, Kolkata, West Bengal, India
| | - Silvina Catuara-Solarz
- Systems Biology Program, Cellular and Systems Neurobiology, Centre for Genomic Regulation, The Barcelona Institute of Science and Technology, Barcelona, Spain.,Universitat Pompeu Fabra, Barcelona, Spain
| | - Mario de La Fuente Revenga
- Department of Physiology and Biophysics, Virginia Commonwealth University, Richmond, VA, United States of America
| | - Alain Marc Guillem
- Laboratorio de Neurotoxicología, Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, México D.F. 07000, Mexico
| | - Mouna Haidar
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Victoria, Australia
| | - Omamuyovwi M Ijomone
- Department of Human Anatomy, Cross River University of Technology, Okuku Campus, Cross River, Nigeria
| | - Bettina Nadorp
- The Department of Biological Chemistry, The Edmond and Lily Safra Center for Brain Sciences, The Alexander Grass Center for Bioengineering, The Hebrew University of Jerusalem, Israel
| | - Lin Qi
- Laboratory of Molecular Neuro-Oncology, Texas Children's Hospital, Baylor College of Medicine, Houston, TX, United States of America
| | - Nirma D Perera
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Victoria, Australia
| | - Louise K Refsgaard
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Kimberley M Reid
- Department of Pharmacology, UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK
| | - Mariam Sabbar
- Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Arghyadip Sahoo
- Department of Biochemistry, Midnapore Medical College, West Bengal University of Health Sciences, West Bengal, India
| | - Natascha Schaefer
- Institute for Clinical Neurobiology, Julius-Maximilians-University of Wuerzburg, Wuerzburg, Germany
| | - Rebecca K Sheean
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Victoria, Australia
| | - Anna Suska
- Department of Molecular and Cellular Neurobiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Rajkumar Verma
- Department of Neurosciences Uconn Health Center, Farmington, CT, United States of America
| | | | - Dean Wright
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Victoria, Australia
| | - Xing-Ding Zhang
- Department of Lymphoma/Myeloma, The University of Texas MD Anderson Cancer Center, Houston, TX, United States of America
| | - Constanze Seidenbecher
- Department for Neurochemistry and Molecular Biology, Leibniz Institute for Neurobiology Magdeburg, Magdeburg, Germany. .,Center for Behavioral Brain Sciences (CBBS) Magdeburg, Magdeburg, Germany.
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23
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Scheyltjens I, Arckens L. The Current Status of Somatostatin-Interneurons in Inhibitory Control of Brain Function and Plasticity. Neural Plast 2016; 2016:8723623. [PMID: 27403348 PMCID: PMC4923604 DOI: 10.1155/2016/8723623] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 05/12/2016] [Indexed: 12/05/2022] Open
Abstract
The mammalian neocortex contains many distinct inhibitory neuronal populations to balance excitatory neurotransmission. A correct excitation/inhibition equilibrium is crucial for normal brain development, functioning, and controlling lifelong cortical plasticity. Knowledge about how the inhibitory network contributes to brain plasticity however remains incomplete. Somatostatin- (SST-) interneurons constitute a large neocortical subpopulation of interneurons, next to parvalbumin- (PV-) and vasoactive intestinal peptide- (VIP-) interneurons. Unlike the extensively studied PV-interneurons, acknowledged as key components in guiding ocular dominance plasticity, the contribution of SST-interneurons is less understood. Nevertheless, SST-interneurons are ideally situated within cortical networks to integrate unimodal or cross-modal sensory information processing and therefore likely to be important mediators of experience-dependent plasticity. The lack of knowledge on SST-interneurons partially relates to the wide variety of distinct subpopulations present in the sensory neocortex. This review informs on those SST-subpopulations hitherto described based on anatomical, molecular, or electrophysiological characteristics and whose functional roles can be attributed based on specific cortical wiring patterns. A possible role for these subpopulations in experience-dependent plasticity will be discussed, emphasizing on learning-induced plasticity and on unimodal and cross-modal plasticity upon sensory loss. This knowledge will ultimately contribute to guide brain plasticity into well-defined directions to restore sensory function and promote lifelong learning.
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Affiliation(s)
- Isabelle Scheyltjens
- Laboratory of Neuroplasticity and Neuroproteomics, KU Leuven, 3000 Leuven, Belgium
| | - Lutgarde Arckens
- Laboratory of Neuroplasticity and Neuroproteomics, KU Leuven, 3000 Leuven, Belgium
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Abstract
Wnt signaling has emerged in recent years as a major player in both nervous system development and adult synaptic plasticity. Of particular relevance to researchers studying learning and memory, Wnt signaling is critical for normal functioning of the hippocampus, a brain region that is essential for many types of memory formation and whose dysfunction is implicated in numerous neurodegenerative and psychiatric conditions. Impaired hippocampal Wnt signaling is implicated in several of these conditions, however, little is known about how Wnt signaling mediates hippocampal memory formation. This review will provide a general overview of Wnt signaling and discuss evidence demonstrating a key role for Wnt signaling in hippocampal memory formation in both normal and disease states. The regulation of Wnt signaling by ovarian sex steroid hormones will also be highlighted, given that the neuroprotection afforded by Wnt-hormone interactions may have significant implications for cognitive function in aging, neurodegenerative disease, and ischemic injury.
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Affiliation(s)
- Ashley M Fortress
- Department of Psychology, University of Wisconsin-Milwaukee, WI, USA
| | - Karyn M Frick
- Department of Psychology, University of Wisconsin-Milwaukee, WI, USA
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25
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Cramer NP, Xu X, F Haydar T, Galdzicki Z. Altered intrinsic and network properties of neocortical neurons in the Ts65Dn mouse model of Down syndrome. Physiol Rep 2015; 3:3/12/e12655. [PMID: 26702072 PMCID: PMC4760451 DOI: 10.14814/phy2.12655] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 11/17/2015] [Indexed: 11/24/2022] Open
Abstract
All individuals with Down syndrome (DS) have a varying but significant degree of cognitive disability. Although hippocampal deficits clearly play an important role, behavioral studies also suggest that deficits within the neocortex contribute to somatosensory deficits and impaired cognition in DS. Using thalamocortical slices from the Ts65Dn mouse model of DS, we investigated the intrinsic and network properties of regular spiking neurons within layer 4 of the somatosensory cortex. In these neurons, the membrane capacitance was increased and specific membrane resistance decreased in slices from Ts65Dn mice. Examination of combined active and passive membrane properties suggests that trisomic layer 4 neurons are less excitable than those from euploid mice. The frequencies of excitatory and inhibitory spontaneous synaptic activities were also reduced in Ts65Dn neurons. With respect to network activity, spontaneous network oscillations (Up states) were shorter and less numerous in the neocortex from Ts65Dn mice when compared to euploid. Up states evoked by electrical stimulation of the ventrobasal nucleus (VBN) of the thalamus were similarly affected in Ts65Dn mice. Additionally, monosynaptic EPSCs and polysynaptic IPSCs evoked by VBN stimulation were significantly delayed in layer 4 regular spiking neurons from Ts65Dn mice. These results indicate that, in the Ts65Dn model of DS, the overall electrophysiological properties of neocortical neurons are altered leading to aberrant network activity within the neocortex. Similar changes in DS individuals may contribute to sensory and cognitive dysfunction and therefore may implicate new targets for cognitive therapies in this developmental disorder.
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Affiliation(s)
- Nathan P Cramer
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine and Center for Neuroscience and Regenerative Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
| | - Xiufen Xu
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine and Center for Neuroscience and Regenerative Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
| | - Tarik F Haydar
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Zygmunt Galdzicki
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine and Center for Neuroscience and Regenerative Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
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26
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Involvement of Potassium and Cation Channels in Hippocampal Abnormalities of Embryonic Ts65Dn and Tc1 Trisomic Mice. EBioMedicine 2015; 2:1048-62. [PMID: 26501103 PMCID: PMC4588457 DOI: 10.1016/j.ebiom.2015.07.038] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Revised: 07/24/2015] [Accepted: 07/28/2015] [Indexed: 01/09/2023] Open
Abstract
Down syndrome (DS) mouse models exhibit cognitive deficits, and are used for studying the neuronal basis of DS pathology. To understand the differences in the physiology of DS model neurons, we used dissociated neuronal cultures from the hippocampi of Ts65Dn and Tc1 DS mice. Imaging of [Ca2+]i and whole cell patch clamp recordings were used to analyze network activity and single neuron properties, respectively. We found a decrease of ~ 30% in both fast (A-type) and slow (delayed rectifier) outward potassium currents. Depolarization of Ts65Dn and Tc1 cells produced fewer spikes than diploid cells. Their network bursts were smaller and slower than diploids, displaying a 40% reduction in Δf / f0 of the calcium signals, and a 30% reduction in propagation velocity. Additionally, Ts65Dn and Tc1 neurons exhibited changes in the action potential shape compared to diploid neurons, with an increase in the amplitude of the action potential, a lower threshold for spiking, and a sharp decrease of about 65% in the after-hyperpolarization amplitude. Numerical simulations reproduced the DS measured phenotype by variations in the conductance of the delayed rectifier and A-type, but necessitated also changes in inward rectifying and M-type potassium channels and in the hyperpolarization-activated cyclic nucleotide-gated (HCN) channels. We therefore conducted whole cell patch clamp measurements of M-type potassium currents, which showed a ~ 90% decrease in Ts65Dn neurons, while HCN measurements displayed an increase of ~ 65% in Ts65Dn cells. Quantitative real-time PCR analysis indicates overexpression of 40% of KCNJ15, an inward rectifying potassium channel, contributing to the increased inhibition. We thus find that changes in several types of potassium channels dominate the observed DS model phenotype. Down syndrome model neurons display altered action potential shape, are less excitable and have decreased potassium currents. The data is accurately described by a numerical simulation that changes conductance of four potassium and the HCN currents. Measurements of the currents related to these four channels, and RT-pcr for a fifth (KCNJ15), confirm the numerical model.
In Down syndrome (DS) cognitive function is impaired, leading us to use cultured hippocampal neuronal networks to investigate the cellular basis of its pathology. DS mouse model neurons are less excitable, produce fewer spikes and generate less network activity. Alterations in several types of potassium currents were detected in these neurons. Numerical simulation of a DS neuron successfully reproduced the experimental results. Beyond extending our understanding of neuronal function and pathology, the alterations in channel conductance can now be targeted with specific drugs so as to point to new directions in therapy of cognitive disabilities of DS.
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Key Words
- 1D, one-dimensional
- 2D, two-dimensional
- DC, direct current
- DS, Down syndrome
- Down syndrome
- EPSC, excitatory post synaptic current
- GABA, gamma-aminobutyric acid
- GIRK, G protein-coupled inwardly-rectifying potassium channels
- HCN, hyperpolarization-activated cyclic nucleotide-gated
- Hippocampus
- Inward rectifiers
- Potassium channels
- Potassium currents
- ROI, region of interest
- RT-PCR, real time polymerase chain reaction
- Reduced excitability
- SEM, standard error of mean
- TTX, tetrodotoxin
- Tc1
- Ts65Dn
- WT, wild type
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27
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Belichenko PV, Kleschevnikov AM, Becker A, Wagner GE, Lysenko LV, Yu YE, Mobley WC. Down Syndrome Cognitive Phenotypes Modeled in Mice Trisomic for All HSA 21 Homologues. PLoS One 2015; 10:e0134861. [PMID: 26230397 PMCID: PMC4521889 DOI: 10.1371/journal.pone.0134861] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Accepted: 07/14/2015] [Indexed: 01/01/2023] Open
Abstract
Down syndrome (DS), trisomy for chromosome 21, is the most common genetic cause of intellectual disability. The genomic regions on human chromosome 21 (HSA21) are syntenically conserved with regions on mouse chromosomes 10, 16, and 17 (Mmu10, Mmu16, and Mmu17). Recently, we created a genetic model of DS which carries engineered duplications of all three mouse syntenic regions homologous to HSA21. This 'triple trisomic' or TTS model thus represents the most complete and accurate murine model currently available for experimental studies of genotype-phenotype relationships in DS. Here we extended our initial studies of TTS mice. Locomotor activity, stereotypic and repetitive behavior, anxiety, working memory, long-term memory, and synaptic plasticity in the dentate gyrus were examined in the TTS and wild-type (WT) control mice. Changes in locomotor activity were most remarkable for a significant increase in ambulatory time and a reduction in average velocity of TTS mice. No changes were detected in repetitive and stereotypic behavior and in measures of anxiety. Working memory showed no changes when tested in Y-maze, but deficiency in a more challenging T-maze test was detected. Furthermore, long-term object recognition memory was significantly reduced in the TTS mice. These changes were accompanied by deficient long-term potentiation in the dentate gyrus, which was restored to the WT levels following blockade of GABAA receptors with picrotoxin (100 μM). TTS mice thus demonstrated a number of phenotypes characteristic of DS and may serve as a new standard by which to evaluate and direct findings in other less complete models of DS.
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Affiliation(s)
- Pavel V. Belichenko
- Department of Neurosciences, School of Medicine, University of California San Diego, La Jolla, CA, 92093–0649, United States of America
| | - Alexander M. Kleschevnikov
- Department of Neurosciences, School of Medicine, University of California San Diego, La Jolla, CA, 92093–0649, United States of America
- * E-mail:
| | - Ann Becker
- Department of Neurosciences, School of Medicine, University of California San Diego, La Jolla, CA, 92093–0649, United States of America
| | - Grant E. Wagner
- Department of Neurosciences, School of Medicine, University of California San Diego, La Jolla, CA, 92093–0649, United States of America
| | - Larisa V. Lysenko
- Department of Neurosciences, School of Medicine, University of California San Diego, La Jolla, CA, 92093–0649, United States of America
| | - Y. Eugene Yu
- Genetics Program and Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY, 14263, United States of America
| | - William C. Mobley
- Department of Neurosciences, School of Medicine, University of California San Diego, La Jolla, CA, 92093–0649, United States of America
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Abstract
OBJECTIVE The main aim of this case series report is to alert physicians to the occurrence of catatonia in Down syndrome (DS). A second aim is to stimulate the study of regression in DS and of catatonia. A subset of individuals with DS is noted to experience unexplained regression in behavior, mood, activities of daily living, motor activities, and intellectual functioning during adolescence or young adulthood. Depression, early onset Alzheimer's, or just "the Down syndrome" are often blamed after general medical causes have been ruled out. Clinicians are generally unaware that catatonia, which can cause these symptoms, may occur in DS. STUDY DESIGN Four DS adolescents who experienced regression are reported. Laboratory tests intended to rule out causes of motor and cognitive regression were within normal limits. Based on the presence of multiple motor disturbances (slowing and/or increased motor activity, grimacing, posturing), the individuals were diagnosed with unspecified catatonia and treated with anti-catatonic treatments (benzodiazepines and electroconvulsive therapy [ECT]). RESULTS All four cases were treated with a benzodiazepine combined with ECT and recovered their baseline functioning. CONCLUSION We suspect catatonia is a common cause of unexplained deterioration in adolescents and young adults with DS. Moreover, pediatricians and others who care for individuals with DS are generally unfamiliar with the catatonia diagnosis outside schizophrenia, resulting in misdiagnosis and years of morbidity. Alerting physicians to catatonia in DS is essential to prompt diagnosis, appropriate treatment, and identification of the frequency and course of this disorder.
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Affiliation(s)
- Neera Ghaziuddin
- Department of Psychiatry, University of Michigan, Ann Arbor, Michigan, USA
| | - Armin Nassiri
- Community Psychiatry, San Jose, California, University of Missouri, Columbia, Missouri, USA
| | - Judith H Miles
- Thompson Center for Autism and Neurodevelopmental Disorders and Department of Child Health, University of Missouri, Columbia, Missouri, USA
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29
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Lysenko LV, Kim J, Henry C, Tyrtyshnaia A, Kohnz RA, Madamba F, Simon GM, Kleschevnikova NE, Nomura DK, Ezekowitz R.AB, Kleschevnikov AM. Monoacylglycerol lipase inhibitor JZL184 improves behavior and neural properties in Ts65Dn mice, a model of down syndrome. PLoS One 2014; 9:e114521. [PMID: 25474204 PMCID: PMC4256450 DOI: 10.1371/journal.pone.0114521] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 11/10/2014] [Indexed: 12/13/2022] Open
Abstract
Genetic alterations or pharmacological treatments affecting endocannabinoid signaling have profound effects on synaptic and neuronal properties and, under certain conditions, may improve higher brain functions. Down syndrome (DS), a developmental disorder caused by triplication of chromosome 21, is characterized by deficient cognition and inevitable development of the Alzheimer disease (AD) type pathology during aging. Here we used JZL184, a selective inhibitor of monoacylglycerol lipase (MAGL), to examine the effects of chronic MAGL inhibition on the behavioral, biochemical, and synaptic properties of aged Ts65Dn mice, a genetic model of DS. In both Ts65Dn mice and their normosomic (2N) controls, JZL184-treatment increased brain levels of 2-arachidonoylglycerol (2-AG) and decreased levels of its metabolites such as arachidonic acid, prostaglandins PGD2, PGE2, PGFα, and PGJ2. Enhanced spontaneous locomotor activity of Ts65Dn mice was reduced by the JZL184-treatement to the levels observed in 2N animals. Deficient long-term memory was also improved, while short-term and working types of memory were unaffected. Furthermore, reduced hippocampal long-term potentiation (LTP) was increased in the JZL184-treated Ts65Dn mice to the levels observed in 2N mice. Interestingly, changes in synaptic plasticity and behavior were not observed in the JZL184-treated 2N mice suggesting that the treatment specifically attenuated the defects in the trisomic animals. The JZL184-treatment also reduced the levels of Aβ40 and Aβ42, but had no effect on the levels of full length APP and BACE1 in both Ts65Dn and 2N mice. These data show that chronic MAGL inhibition improves the behavior and brain functions in a DS model suggesting that pharmacological targeting of MAGL may be considered as a perspective new approach for improving cognition in DS.
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Affiliation(s)
- Larisa V. Lysenko
- Department of Neurosciences, University of California San Diego, La Jolla, CA, United States of America
| | - Jeesun Kim
- Department of Neurosciences, University of California San Diego, La Jolla, CA, United States of America
| | - Cassandra Henry
- Abide Therapeutics, Inc., San Diego, CA, United States of America
| | - Anna Tyrtyshnaia
- School of Biomedicine, Far Eastern Federal University, Sukhanova 8, Vladivostok, Russian Federation
| | - Rebecca A. Kohnz
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California, United States of America
| | - Francisco Madamba
- Department of Neurosciences, University of California San Diego, La Jolla, CA, United States of America
| | - Gabriel M. Simon
- Abide Therapeutics, Inc., San Diego, CA, United States of America
| | - Natalia E. Kleschevnikova
- Department of Neurosciences, University of California San Diego, La Jolla, CA, United States of America
| | - Daniel K. Nomura
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California, United States of America
| | | | - Alexander M. Kleschevnikov
- Department of Neurosciences, University of California San Diego, La Jolla, CA, United States of America
- * E-mail:
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30
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Das D, Phillips C, Hsieh W, Sumanth K, Dang V, Salehi A. Neurotransmitter-based strategies for the treatment of cognitive dysfunction in Down syndrome. Prog Neuropsychopharmacol Biol Psychiatry 2014; 54:140-8. [PMID: 24842803 DOI: 10.1016/j.pnpbp.2014.05.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Revised: 05/08/2014] [Accepted: 05/08/2014] [Indexed: 01/10/2023]
Abstract
Down syndrome (DS) is a multisystem disorder affecting the cardiovascular, respiratory, gastrointestinal, neurological, hematopoietic, and musculoskeletal systems and is characterized by significant cognitive disability and a possible common pathogenic mechanism with Alzheimer's disease. During the last decade, numerous studies have supported the notion that the triplication of specific genes on human chromosome 21 plays a significant role in cognitive dysfunction in DS. Here we reviewed studies in trisomic mouse models and humans, including children and adults with DS. In order to identify groups of genes that contribute to cognitive disability in DS, multiple mouse models of DS with segmental trisomy have been generated. Over-expression of these particular genes in DS can lead to dysfunction of several neurotransmitter systems. Therapeutic strategies for DS have either focused on normalizing the expression of triplicated genes with important roles in DS or restoring the function of these systems. Indeed, our extensive review of studies on the pathogenesis of DS suggests that one plausible strategy for the treatment of cognitive dysfunction is to target the cholinergic, serotonergic, GABA-ergic, glutamatergic, and norepinephrinergic system. However, a fundamental strategy for treatment of cognitive dysfunction in DS would include reducing to normal levels the expression of specific triplicated genes in affected systems before the onset of neurodegeneration.
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Affiliation(s)
- Devsmita Das
- VA Palo Alto Health Care System, 3801 Miranda Ave., Palo Alto, CA, USA; Department of Psychiatry & Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94304, USA
| | - Cristy Phillips
- Department of Physical Therapy, P.O. Box 910, Arkansas State University, State University, AR, USA
| | - Wayne Hsieh
- VA Palo Alto Health Care System, 3801 Miranda Ave., Palo Alto, CA, USA
| | - Krithika Sumanth
- VA Palo Alto Health Care System, 3801 Miranda Ave., Palo Alto, CA, USA
| | - Van Dang
- VA Palo Alto Health Care System, 3801 Miranda Ave., Palo Alto, CA, USA; Department of Psychiatry & Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94304, USA
| | - Ahmad Salehi
- VA Palo Alto Health Care System, 3801 Miranda Ave., Palo Alto, CA, USA; Department of Psychiatry & Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94304, USA.
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Hussaini SMQ, Choi CI, Cho CH, Kim HJ, Jun H, Jang MH. Wnt signaling in neuropsychiatric disorders: ties with adult hippocampal neurogenesis and behavior. Neurosci Biobehav Rev 2014; 47:369-83. [PMID: 25263701 DOI: 10.1016/j.neubiorev.2014.09.005] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Revised: 07/20/2014] [Accepted: 09/05/2014] [Indexed: 12/27/2022]
Abstract
In an effort to better understand and treat mental disorders, the Wnt pathway and adult hippocampal neurogenesis have received increased attention in recent years. One is a signaling pathway regulating key aspects of embryonic patterning, cell specification and adult tissue homeostasis. The other is the generation of newborn neurons in adulthood that integrate into the neural circuit and function in learning and memory, and mood behavior. In this review, we discuss the growing relationship between Wnt signaling-mediated regulation of adult hippocampal neurogenesis as it applies to neuropsychiatric disorders. Evidence suggests dysfunctional Wnt signaling may aberrantly regulate new neuron development and cognitive function. Indeed, altered expression of key Wnt pathway components are observed in the hippocampus of patients suffering from neuropsychiatric disorders. Clinically-utilized mood stabilizers also proceed through modulation of Wnt signaling in the hippocampus, while Wnt pathway antagonists can regulate the antidepressant response. Here, we review the role of Wnt signaling in disease etiology and pathogenesis, regulation of adult neurogenesis and behavior, and the therapeutic targeting of disease symptoms.
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Affiliation(s)
| | - Chan-Il Choi
- Department of Neurologic Surgery, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN, USA
| | - Chang Hoon Cho
- Department of Neurologic Surgery, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN, USA
| | - Hyo Jin Kim
- Department of Neurologic Surgery, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN, USA
| | - Heechul Jun
- Department of Neurologic Surgery, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN, USA
| | - Mi-Hyeon Jang
- Department of Neurologic Surgery, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN, USA; Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, MN, USA.
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New Innovations: Therapies for Genetic Conditions. CURRENT GENETIC MEDICINE REPORTS 2014. [DOI: 10.1007/s40142-014-0043-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Glutamatergic transmission aberration: a major cause of behavioral deficits in a murine model of Down's syndrome. J Neurosci 2014; 34:5099-106. [PMID: 24719089 DOI: 10.1523/jneurosci.5338-13.2014] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Trisomy 21, or Down's syndrome (DS), is the most common genetic cause of intellectual disability. Altered neurotransmission in the brains of DS patients leads to hippocampus-dependent learning and memory deficiency. Although genetic mouse models have provided important insights into the genes and mechanisms responsible for DS-specific changes, the molecular mechanisms leading to memory deficits are not clear. We investigated whether the segmental trisomy model of DS, Ts[Rb(12.1716)]2Cje (Ts2), exhibits hippocampal glutamatergic transmission abnormalities and whether these alterations cause behavioral deficits. Behavioral assays demonstrated that Ts2 mice display a deficit in nest building behavior, a measure of hippocampus-dependent nonlearned behavior, as well as dysfunctional hippocampus-dependent spatial memory tested in the object-placement and the Y-maze spontaneous alternation tasks. Magnetic resonance spectra measured in the hippocampi revealed a significantly lower glutamate concentration in Ts2 as compared with normal disomic (2N) littermates. The glutamate deficit accompanied hippocampal NMDA receptor1 (NMDA-R1) mRNA and protein expression level downregulation in Ts2 compared with 2N mice. In concert with these alterations, paired-pulse analyses suggested enhanced synaptic inhibition and/or lack of facilitation in the dentate gyrus of Ts2 compared with 2N mice. Ts2 mice also exhibited disrupted synaptic plasticity in slice recordings of the hippocampal CA1 region. Collectively, these findings imply that deficits in glutamate and NMDA-R1 may be responsible for impairments in synaptic plasticity in the hippocampus associated with behavioral dysfunctions in Ts2 mice. Thus, these findings suggest that glutamatergic deficits have a significant role in causing intellectual disabilities in DS.
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Corrales A, Vidal R, García S, Vidal V, Martínez P, García E, Flórez J, Sanchez-Barceló EJ, Martínez-Cué C, Rueda N. Chronic melatonin treatment rescues electrophysiological and neuromorphological deficits in a mouse model of Down syndrome. J Pineal Res 2014; 56:51-61. [PMID: 24147912 DOI: 10.1111/jpi.12097] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 09/20/2013] [Indexed: 12/22/2022]
Abstract
The Ts65Dn mouse (TS), the most commonly used model of Down syndrome (DS), exhibits several key phenotypic characteristics of this condition. In particular, these animals present hypocellularity in different areas of their CNS due to impaired neurogenesis and have alterations in synaptic plasticity that compromise their cognitive performance. In addition, increases in oxidative stress during adulthood contribute to the age-related progression of cognitive and neuronal deterioration. We have previously demonstrated that chronic melatonin treatment improves learning and memory and reduces cholinergic neurodegeneration in TS mice. However, the molecular and physiological mechanisms that mediate these beneficial cognitive effects are not yet fully understood. In this study, we analyzed the effects of chronic melatonin treatment on different mechanisms that have been proposed to underlie the cognitive impairments observed in TS mice: reduced neurogenesis, altered synaptic plasticity, enhanced synaptic inhibition and oxidative damage. Chronic melatonin treatment rescued both impaired adult neurogenesis and the decreased density of hippocampal granule cells in trisomic mice. In addition, melatonin administration reduced synaptic inhibition in TS mice by increasing the density and/or activity of glutamatergic synapses in the hippocampus. These effects were accompanied by a full recovery of hippocampal LTP in trisomic animals. Finally, melatonin treatment decreased the levels of lipid peroxidation in the hippocampus of TS mice. These results indicate that the cognitive-enhancing effects of melatonin in adult TS mice could be mediated by the normalization of their electrophysiological and neuromorphological abnormalities and suggest that melatonin represents an effective treatment in retarding the progression of DS neuropathology.
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Affiliation(s)
- Andrea Corrales
- Department of Physiology and Pharmacology, School of Medicine, University of Cantabria, Santander, Spain
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35
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Picker JD, Walsh CA. New innovations: therapeutic opportunities for intellectual disabilities. Ann Neurol 2013; 74:382-90. [PMID: 24038210 DOI: 10.1002/ana.24002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Revised: 07/01/2013] [Accepted: 07/29/2013] [Indexed: 12/25/2022]
Abstract
Intellectual disability is common and is associated with significant morbidity. Until the latter half of the 20th century, there were no efficacious treatments. Following initial breakthroughs associated with newborn screening and metabolic corrections, little progress was made until recently. With improved understanding of genetic and cellular mechanisms, novel treatment options are beginning to appear for a number of specific conditions. Fragile X and tuberous sclerosis offer paradigms for the development of targeted therapeutics, but advances in understanding of other disorders such as Down syndrome and Rett syndrome, for example, are also resulting in promising treatment directions. In addition, better understanding of the underlying neurobiology is leading to novel developments in enzyme replacement for storage disorders and adjunctive therapies for metabolic disorders, as well as potentially more generalizable approaches that target dysfunctional cell regulation via RNA and chromatin. Physiologic therapies, including deep brain stimulation and transcranial magnetic stimulation, offer yet another direction to enhance cognitive functioning. Current options and evolving opportunities for the intellectually disabled are reviewed and exemplified.
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Affiliation(s)
- Jonathan D Picker
- Division of Genetics, Boston Children's Hospital, and Howard Hughes Medical Institute, Boston, MA; Departments of Pediatrics and Neurology,, Harvard Medical School, Boston, MA
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Szemes M, Davies RL, Garden CLP, Usowicz MM. Weaker control of the electrical properties of cerebellar granule cells by tonically active GABAA receptors in the Ts65Dn mouse model of Down's syndrome. Mol Brain 2013; 6:33. [PMID: 23870245 PMCID: PMC3723448 DOI: 10.1186/1756-6606-6-33] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 07/14/2013] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Down's syndrome (DS) is caused by triplication of all or part of human chromosome 21 and is characterized by a decrease in the overall size of the brain. One of the brain regions most affected is the cerebellum, in which the number of granule cells (GCs) is markedly decreased. GCs process sensory information entering the cerebellum via mossy fibres and pass it on to Purkinje cells and inhibitory interneurons. How GCs transform incoming signals depends on their input-output relationship, which is adjusted by tonically active GABA(A) receptor channels. RESULTS We report that in the Ts65Dn mouse model of DS, in which cerebellar volume and GC number are decreased as in DS, the tonic GABA(A) receptor current in GCs is smaller than in wild-type mice and is less effective in moderating input resistance and raising the minimum current required for action potential firing. We also find that tonically active GABA(A) receptors curb the height and broaden the width of action potentials in wild-type GCs but not in Ts65Dn GCs. Single-cell real-time quantitative PCR reveals that these electrical differences are accompanied by decreased expression of the gene encoding the GABA(A) receptor β3 subunit but not genes coding for some of the other GABA(A) receptor subunits expressed in GCs (α1, α6, β2 and δ). CONCLUSIONS Weaker moderation of excitability and action potential waveform in GCs of the Ts65Dn mouse by tonically active GABA(A) receptors is likely to contribute to atypical transfer of information through the cerebellum. Similar changes may occur in DS.
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Affiliation(s)
- Marianna Szemes
- Present address: School of Cellular and Molecular Medicine, University of Bristol, University Walk, Bristol BS8 1TD, UK
| | - Rachel L Davies
- Present address: Research & Enterprise Development, University of Bristol, Senate House, Tyndall Avenue, Bristol BS8 1TH, UK
| | - Claire LP Garden
- Present address: School of Life, Sport and Social Sciences, Edinburgh Napier University, Sighthill Court, Edinburgh EH11 4BN, UK
| | - Maria M Usowicz
- School of Physiology & Pharmacology, University of Bristol, University Walk, Bristol BS8 1TD, UK
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Abstract
Down syndrome is the most common form of intellectual disability and results from one of the most complex genetic perturbations that is compatible with survival, trisomy 21. The study of brain dysfunction in this disorder has largely been based on a gene discovery approach, but we are now moving into an era of functional genome exploration, in which the effects of individual genes are being studied alongside the effects of deregulated non-coding genetic elements and epigenetic influences. Also, new data from functional neuroimaging studies are challenging our views of the cognitive phenotypes associated with Down syndrome and their pathophysiological correlates. These advances hold promise for the development of treatments for intellectual disability.
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Affiliation(s)
- Mara Dierssen
- Genes and Disease Programme, Centre for Genomic Regulation (CRG), Universitat Pompeu Fabra, Centro de Investigación Biomédica en Red de Enfermedades Raras, E-08003 Barcelona, Spain.
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