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Wollman LB, Flanigan EG, Fregosi RF. Chronic, episodic nicotine exposure alters GABAergic synaptic transmission to hypoglossal motor neurons and genioglossus muscle function at a critical developmental age. J Neurophysiol 2022; 128:1483-1500. [PMID: 36350047 PMCID: PMC9722256 DOI: 10.1152/jn.00397.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 11/02/2022] [Accepted: 11/03/2022] [Indexed: 11/11/2022] Open
Abstract
Regulation of GABAergic signaling through nicotinic acetylcholine receptor (nAChR) activation is critical for neuronal development. Here, we test the hypothesis that chronic episodic developmental nicotine exposure (eDNE) disrupts GABAergic signaling, leading to dysfunction of hypoglossal motor neurons (XIIMNs), which innervate the tongue muscles. We studied control and eDNE pups at two developmentally vulnerable age ranges: postnatal days (P)1-5 and P10-12. The amplitude and frequency of spontaneous and miniature inhibitory postsynaptic currents (sIPSCs, mIPSCs) at baseline were not altered by eDNE at either age. In contrast, eDNE increased GABAAR-α1 receptor expression on XIIMNs and, in the older group, the postsynaptic response to muscimol (GABAA receptor agonist). Activation of nAChRs with exogenous nicotine increased the frequency of GABAergic sIPSCs in control and eDNE neurons at P1-5. By P10-12, acute nicotine increased sIPSC frequency in eDNE but not control neurons. In vivo experiments showed that the breathing-related activation of tongue muscles, which are innervated by XIIMNs, is reduced at P10-12. This effect was partially mitigated by subcutaneous muscimol, but only in the eDNE pups. Taken together, these data indicate that eDNE alters GABAergic transmission to XIIMNs at a critical developmental age, and this is expressed as reduced breathing-related drive to XIIMNs in vivo.NEW & NOTEWORTHY Here, we provide a thorough assessment of the effects of nicotine exposure on GABAergic synaptic transmission, from the cellular to the systems level. This work makes significant advances in our understanding of the impact of nicotine exposure during development on GABAergic neurotransmission within the respiratory network and the potential role this plays in the excitatory/inhibitory imbalance that is thought to be an important mechanism underlying neonatal breathing disorders, including sudden infant death syndrome.
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Affiliation(s)
- Lila Buls Wollman
- Department of Physiology, The University of Arizona, Tucson, Arizona
| | | | - Ralph F Fregosi
- Department of Physiology, The University of Arizona, Tucson, Arizona
- Department of Neuroscience, The University of Arizona, Tucson, Arizona
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Branchereau P, Cattaert D. Chloride Homeostasis in Developing Motoneurons. ADVANCES IN NEUROBIOLOGY 2022; 28:45-61. [PMID: 36066820 DOI: 10.1007/978-3-031-07167-6_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Maturation of GABA/Glycine chloride-mediated synaptic inhibitions is crucial for the establishment of a balance between excitation and inhibition. GABA and glycine are excitatory neurotransmitters on immature neurons that exhibit elevated [Cl-]i. Later in development [Cl-]i drops leading to the occurrence of inhibitory synaptic activity. This ontogenic change is closely correlated to a differential expression of two cation-chloride cotransporters that are the Cl- channel K+/Cl- co-transporter type 2 (KCC2) that extrudes Cl- ions and the Na+-K+-2Cl- cotransporter NKCC1 that accumulates Cl- ions. The classical scheme built from studies performed on cortical and hippocampal networks proposes that immature neurons display high [Cl-]i because NKCC1 is overexpressed compared to KCC2 and that the co-transporters ratio reverses in mature neurons, lowering [Cl-]i. In this chapter, we will see that this classical scheme is not true in motoneurons (MNs) and that an early alteration of the chloride homeostasis may be involved in pathological conditions.
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Affiliation(s)
- Pascal Branchereau
- Institut de Neurosciences Cognitives et Intégratives d'Aquitaine (INCIA), Univ. Bordeaux, UMR 5287, CNRS, Bordeaux, France.
| | - Daniel Cattaert
- Institut de Neurosciences Cognitives et Intégratives d'Aquitaine (INCIA), Univ. Bordeaux, UMR 5287, CNRS, Bordeaux, France
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Vieira N, Rito T, Correia-Neves M, Sousa N. Sorting Out Sorting Nexins Functions in the Nervous System in Health and Disease. Mol Neurobiol 2021; 58:4070-4106. [PMID: 33931804 PMCID: PMC8280035 DOI: 10.1007/s12035-021-02388-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 04/05/2021] [Indexed: 12/18/2022]
Abstract
Endocytosis is a fundamental process that controls protein/lipid composition of the plasma membrane, thereby shaping cellular metabolism, sensing, adhesion, signaling, and nutrient uptake. Endocytosis is essential for the cell to adapt to its surrounding environment, and a tight regulation of the endocytic mechanisms is required to maintain cell function and survival. This is particularly significant in the central nervous system (CNS), where composition of neuronal cell surface is crucial for synaptic functioning. In fact, distinct pathologies of the CNS are tightly linked to abnormal endolysosomal function, and several genome wide association analysis (GWAS) and biochemical studies have identified intracellular trafficking regulators as genetic risk factors for such pathologies. The sorting nexins (SNXs) are a family of proteins involved in protein trafficking regulation and signaling. SNXs dysregulation occurs in patients with Alzheimer’s disease (AD), Down’s syndrome (DS), schizophrenia, ataxia and epilepsy, among others, establishing clear roles for this protein family in pathology. Interestingly, restoration of SNXs levels has been shown to trigger synaptic plasticity recovery in a DS mouse model. This review encompasses an historical and evolutionary overview of SNXs protein family, focusing on its organization, phyla conservation, and evolution throughout the development of the nervous system during speciation. We will also survey SNXs molecular interactions and highlight how defects on SNXs underlie distinct pathologies of the CNS. Ultimately, we discuss possible strategies of intervention, surveying how our knowledge about the fundamental processes regulated by SNXs can be applied to the identification of novel therapeutic avenues for SNXs-related disorders.
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Affiliation(s)
- Neide Vieira
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057, Braga, Portugal. .,ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal.
| | - Teresa Rito
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057, Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Margarida Correia-Neves
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057, Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Nuno Sousa
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057, Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
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Boeri J, Meunier C, Le Corronc H, Branchereau P, Timofeeva Y, Lejeune FX, Mouffle C, Arulkandarajah H, Mangin JM, Legendre P, Czarnecki A. Two opposite voltage-dependent currents control the unusual early development pattern of embryonic Renshaw cell electrical activity. eLife 2021; 10:62639. [PMID: 33899737 PMCID: PMC8139835 DOI: 10.7554/elife.62639] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 04/24/2021] [Indexed: 11/25/2022] Open
Abstract
Renshaw cells (V1R) are excitable as soon as they reach their final location next to the spinal motoneurons and are functionally heterogeneous. Using multiple experimental approaches, in combination with biophysical modeling and dynamical systems theory, we analyzed, for the first time, the mechanisms underlying the electrophysiological properties of V1R during early embryonic development of the mouse spinal cord locomotor networks (E11.5–E16.5). We found that these interneurons are subdivided into several functional clusters from E11.5 and then display an unexpected transitory involution process during which they lose their ability to sustain tonic firing. We demonstrated that the essential factor controlling the diversity of the discharge pattern of embryonic V1R is the ratio of a persistent sodium conductance to a delayed rectifier potassium conductance. Taken together, our results reveal how a simple mechanism, based on the synergy of two voltage-dependent conductances that are ubiquitous in neurons, can produce functional diversity in embryonic V1R and control their early developmental trajectory.
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Affiliation(s)
- Juliette Boeri
- INSERM, UMR_S 1130, CNRS, UMR 8246, Neuroscience Paris Seine, Institute of Biology Paris Seine, Sorbonne Univ, Paris, France
| | - Claude Meunier
- Centre de Neurosciences Intégratives et Cognition, CNRS UMR 8002, Institut Neurosciences et Cognition, Université de Paris, Paris, France
| | - Hervé Le Corronc
- INSERM, UMR_S 1130, CNRS, UMR 8246, Neuroscience Paris Seine, Institute of Biology Paris Seine, Sorbonne Univ, Paris, France.,Univ Angers, Angers, France
| | | | - Yulia Timofeeva
- Department of Computer Science and Centre for Complexity Science, University of Warwick, Coventry, United Kingdom.,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - François-Xavier Lejeune
- Institut du Cerveau et de la Moelle Epinière, Centre de Recherche CHU Pitié-Salpétrière, INSERM, U975, CNRS, UMR 7225, Sorbonne Univ, Paris, France
| | - Christine Mouffle
- INSERM, UMR_S 1130, CNRS, UMR 8246, Neuroscience Paris Seine, Institute of Biology Paris Seine, Sorbonne Univ, Paris, France
| | - Hervé Arulkandarajah
- INSERM, UMR_S 1130, CNRS, UMR 8246, Neuroscience Paris Seine, Institute of Biology Paris Seine, Sorbonne Univ, Paris, France
| | - Jean Marie Mangin
- INSERM, UMR_S 1130, CNRS, UMR 8246, Neuroscience Paris Seine, Institute of Biology Paris Seine, Sorbonne Univ, Paris, France
| | - Pascal Legendre
- INSERM, UMR_S 1130, CNRS, UMR 8246, Neuroscience Paris Seine, Institute of Biology Paris Seine, Sorbonne Univ, Paris, France
| | - Antonny Czarnecki
- INSERM, UMR_S 1130, CNRS, UMR 8246, Neuroscience Paris Seine, Institute of Biology Paris Seine, Sorbonne Univ, Paris, France.,Univ. Bordeaux, CNRS, EPHE, INCIA, Bordeaux, France
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Vucic S, Higashihara M, Sobue G, Atsuta N, Doi Y, Kuwabara S, Kim SH, Kim I, Oh KW, Park J, Kim EM, Talman P, Menon P, Kiernan MC. ALS is a multistep process in South Korean, Japanese, and Australian patients. Neurology 2020; 94:e1657-e1663. [PMID: 32071166 PMCID: PMC7251515 DOI: 10.1212/wnl.0000000000009015] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 11/08/2019] [Indexed: 12/19/2022] Open
Abstract
OBJECTIVE To establish whether amyotrophic lateral sclerosis (ALS) is a multistep process in South Korean and Japanese populations when compared to Australian cohorts. METHODS We generated incident data by age and sex for Japanese (collected between April 2009 and March 2010) and South Korean patients with ALS (collected between January 2011 and December 2015). Mortality rates were provided for Australian patients with ALS (collected between 2007 and 2016). We regressed the log of age-specific incidence against the log of age with least squares regression for each ALS population. RESULTS We identified 11,834 cases of ALS from the 3 populations, including 6,524 Australian, 2,264 Japanese, and 3,049 South Korean ALS cases. We established a linear relation between the log incidence and log age in the 3 populations: Australia r 2 = 0.99, Japan r 2 = 0.99, South Korea r 2 = 0.99. The estimate slopes were similar across the 3 populations, being 5.4 (95% confidence interval [CI], 4.8-5.5) in Japanese, 5.4 (95% CI, 5.2-5.7) in Australian, and 4.4 (95% CI, 4.2-4.8) in South Korean patients. CONCLUSIONS The linear relationship between log age and log incidence is consistent with a multistage model of disease, with slope estimated suggesting that 6 steps were required in Japanese and Australian patients with ALS while 5 steps were needed in South Korean patients. Identification of these steps could identify novel therapeutic strategies.
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Affiliation(s)
- Steve Vucic
- From the Westmead Clinical School (S.V., M.H., P.M.), University of Sydney, Australia; Department of Neurology (N.A.), Nagoya University Graduate School of Medicine (G.S.); The National Institute of Public Health (Y.D.), Wako-shi; Chiba University Graduate School of Medicine (S.K.), Japan; Department of Neurology (S.H.K., K.-W.O., J.P.), Hanyang University Hospital; Department of Health Sciences (I.K., E.M.K.), Hanyang University Graduate School; Department of Occupational and Environmental Medicine (I.K.), College of Medicine, Hanyang University, Seoul, Republic of Korea; Geelong Hospital (P.T.); and Brain and Mind Centre (M.C.K.), University of Sydney and Institute of Clinical Neurosciences, Royal Prince Alfred Hospital, Sydney, Australia.
| | - Mana Higashihara
- From the Westmead Clinical School (S.V., M.H., P.M.), University of Sydney, Australia; Department of Neurology (N.A.), Nagoya University Graduate School of Medicine (G.S.); The National Institute of Public Health (Y.D.), Wako-shi; Chiba University Graduate School of Medicine (S.K.), Japan; Department of Neurology (S.H.K., K.-W.O., J.P.), Hanyang University Hospital; Department of Health Sciences (I.K., E.M.K.), Hanyang University Graduate School; Department of Occupational and Environmental Medicine (I.K.), College of Medicine, Hanyang University, Seoul, Republic of Korea; Geelong Hospital (P.T.); and Brain and Mind Centre (M.C.K.), University of Sydney and Institute of Clinical Neurosciences, Royal Prince Alfred Hospital, Sydney, Australia
| | - Gen Sobue
- From the Westmead Clinical School (S.V., M.H., P.M.), University of Sydney, Australia; Department of Neurology (N.A.), Nagoya University Graduate School of Medicine (G.S.); The National Institute of Public Health (Y.D.), Wako-shi; Chiba University Graduate School of Medicine (S.K.), Japan; Department of Neurology (S.H.K., K.-W.O., J.P.), Hanyang University Hospital; Department of Health Sciences (I.K., E.M.K.), Hanyang University Graduate School; Department of Occupational and Environmental Medicine (I.K.), College of Medicine, Hanyang University, Seoul, Republic of Korea; Geelong Hospital (P.T.); and Brain and Mind Centre (M.C.K.), University of Sydney and Institute of Clinical Neurosciences, Royal Prince Alfred Hospital, Sydney, Australia
| | - Naoki Atsuta
- From the Westmead Clinical School (S.V., M.H., P.M.), University of Sydney, Australia; Department of Neurology (N.A.), Nagoya University Graduate School of Medicine (G.S.); The National Institute of Public Health (Y.D.), Wako-shi; Chiba University Graduate School of Medicine (S.K.), Japan; Department of Neurology (S.H.K., K.-W.O., J.P.), Hanyang University Hospital; Department of Health Sciences (I.K., E.M.K.), Hanyang University Graduate School; Department of Occupational and Environmental Medicine (I.K.), College of Medicine, Hanyang University, Seoul, Republic of Korea; Geelong Hospital (P.T.); and Brain and Mind Centre (M.C.K.), University of Sydney and Institute of Clinical Neurosciences, Royal Prince Alfred Hospital, Sydney, Australia
| | - Yuriko Doi
- From the Westmead Clinical School (S.V., M.H., P.M.), University of Sydney, Australia; Department of Neurology (N.A.), Nagoya University Graduate School of Medicine (G.S.); The National Institute of Public Health (Y.D.), Wako-shi; Chiba University Graduate School of Medicine (S.K.), Japan; Department of Neurology (S.H.K., K.-W.O., J.P.), Hanyang University Hospital; Department of Health Sciences (I.K., E.M.K.), Hanyang University Graduate School; Department of Occupational and Environmental Medicine (I.K.), College of Medicine, Hanyang University, Seoul, Republic of Korea; Geelong Hospital (P.T.); and Brain and Mind Centre (M.C.K.), University of Sydney and Institute of Clinical Neurosciences, Royal Prince Alfred Hospital, Sydney, Australia
| | - Satoshi Kuwabara
- From the Westmead Clinical School (S.V., M.H., P.M.), University of Sydney, Australia; Department of Neurology (N.A.), Nagoya University Graduate School of Medicine (G.S.); The National Institute of Public Health (Y.D.), Wako-shi; Chiba University Graduate School of Medicine (S.K.), Japan; Department of Neurology (S.H.K., K.-W.O., J.P.), Hanyang University Hospital; Department of Health Sciences (I.K., E.M.K.), Hanyang University Graduate School; Department of Occupational and Environmental Medicine (I.K.), College of Medicine, Hanyang University, Seoul, Republic of Korea; Geelong Hospital (P.T.); and Brain and Mind Centre (M.C.K.), University of Sydney and Institute of Clinical Neurosciences, Royal Prince Alfred Hospital, Sydney, Australia
| | - Seung Hyun Kim
- From the Westmead Clinical School (S.V., M.H., P.M.), University of Sydney, Australia; Department of Neurology (N.A.), Nagoya University Graduate School of Medicine (G.S.); The National Institute of Public Health (Y.D.), Wako-shi; Chiba University Graduate School of Medicine (S.K.), Japan; Department of Neurology (S.H.K., K.-W.O., J.P.), Hanyang University Hospital; Department of Health Sciences (I.K., E.M.K.), Hanyang University Graduate School; Department of Occupational and Environmental Medicine (I.K.), College of Medicine, Hanyang University, Seoul, Republic of Korea; Geelong Hospital (P.T.); and Brain and Mind Centre (M.C.K.), University of Sydney and Institute of Clinical Neurosciences, Royal Prince Alfred Hospital, Sydney, Australia
| | - Inah Kim
- From the Westmead Clinical School (S.V., M.H., P.M.), University of Sydney, Australia; Department of Neurology (N.A.), Nagoya University Graduate School of Medicine (G.S.); The National Institute of Public Health (Y.D.), Wako-shi; Chiba University Graduate School of Medicine (S.K.), Japan; Department of Neurology (S.H.K., K.-W.O., J.P.), Hanyang University Hospital; Department of Health Sciences (I.K., E.M.K.), Hanyang University Graduate School; Department of Occupational and Environmental Medicine (I.K.), College of Medicine, Hanyang University, Seoul, Republic of Korea; Geelong Hospital (P.T.); and Brain and Mind Centre (M.C.K.), University of Sydney and Institute of Clinical Neurosciences, Royal Prince Alfred Hospital, Sydney, Australia
| | - Ki-Wook Oh
- From the Westmead Clinical School (S.V., M.H., P.M.), University of Sydney, Australia; Department of Neurology (N.A.), Nagoya University Graduate School of Medicine (G.S.); The National Institute of Public Health (Y.D.), Wako-shi; Chiba University Graduate School of Medicine (S.K.), Japan; Department of Neurology (S.H.K., K.-W.O., J.P.), Hanyang University Hospital; Department of Health Sciences (I.K., E.M.K.), Hanyang University Graduate School; Department of Occupational and Environmental Medicine (I.K.), College of Medicine, Hanyang University, Seoul, Republic of Korea; Geelong Hospital (P.T.); and Brain and Mind Centre (M.C.K.), University of Sydney and Institute of Clinical Neurosciences, Royal Prince Alfred Hospital, Sydney, Australia
| | - Jinseok Park
- From the Westmead Clinical School (S.V., M.H., P.M.), University of Sydney, Australia; Department of Neurology (N.A.), Nagoya University Graduate School of Medicine (G.S.); The National Institute of Public Health (Y.D.), Wako-shi; Chiba University Graduate School of Medicine (S.K.), Japan; Department of Neurology (S.H.K., K.-W.O., J.P.), Hanyang University Hospital; Department of Health Sciences (I.K., E.M.K.), Hanyang University Graduate School; Department of Occupational and Environmental Medicine (I.K.), College of Medicine, Hanyang University, Seoul, Republic of Korea; Geelong Hospital (P.T.); and Brain and Mind Centre (M.C.K.), University of Sydney and Institute of Clinical Neurosciences, Royal Prince Alfred Hospital, Sydney, Australia
| | - Eun Mi Kim
- From the Westmead Clinical School (S.V., M.H., P.M.), University of Sydney, Australia; Department of Neurology (N.A.), Nagoya University Graduate School of Medicine (G.S.); The National Institute of Public Health (Y.D.), Wako-shi; Chiba University Graduate School of Medicine (S.K.), Japan; Department of Neurology (S.H.K., K.-W.O., J.P.), Hanyang University Hospital; Department of Health Sciences (I.K., E.M.K.), Hanyang University Graduate School; Department of Occupational and Environmental Medicine (I.K.), College of Medicine, Hanyang University, Seoul, Republic of Korea; Geelong Hospital (P.T.); and Brain and Mind Centre (M.C.K.), University of Sydney and Institute of Clinical Neurosciences, Royal Prince Alfred Hospital, Sydney, Australia
| | - Paul Talman
- From the Westmead Clinical School (S.V., M.H., P.M.), University of Sydney, Australia; Department of Neurology (N.A.), Nagoya University Graduate School of Medicine (G.S.); The National Institute of Public Health (Y.D.), Wako-shi; Chiba University Graduate School of Medicine (S.K.), Japan; Department of Neurology (S.H.K., K.-W.O., J.P.), Hanyang University Hospital; Department of Health Sciences (I.K., E.M.K.), Hanyang University Graduate School; Department of Occupational and Environmental Medicine (I.K.), College of Medicine, Hanyang University, Seoul, Republic of Korea; Geelong Hospital (P.T.); and Brain and Mind Centre (M.C.K.), University of Sydney and Institute of Clinical Neurosciences, Royal Prince Alfred Hospital, Sydney, Australia
| | - Parvathi Menon
- From the Westmead Clinical School (S.V., M.H., P.M.), University of Sydney, Australia; Department of Neurology (N.A.), Nagoya University Graduate School of Medicine (G.S.); The National Institute of Public Health (Y.D.), Wako-shi; Chiba University Graduate School of Medicine (S.K.), Japan; Department of Neurology (S.H.K., K.-W.O., J.P.), Hanyang University Hospital; Department of Health Sciences (I.K., E.M.K.), Hanyang University Graduate School; Department of Occupational and Environmental Medicine (I.K.), College of Medicine, Hanyang University, Seoul, Republic of Korea; Geelong Hospital (P.T.); and Brain and Mind Centre (M.C.K.), University of Sydney and Institute of Clinical Neurosciences, Royal Prince Alfred Hospital, Sydney, Australia
| | - Matthew C Kiernan
- From the Westmead Clinical School (S.V., M.H., P.M.), University of Sydney, Australia; Department of Neurology (N.A.), Nagoya University Graduate School of Medicine (G.S.); The National Institute of Public Health (Y.D.), Wako-shi; Chiba University Graduate School of Medicine (S.K.), Japan; Department of Neurology (S.H.K., K.-W.O., J.P.), Hanyang University Hospital; Department of Health Sciences (I.K., E.M.K.), Hanyang University Graduate School; Department of Occupational and Environmental Medicine (I.K.), College of Medicine, Hanyang University, Seoul, Republic of Korea; Geelong Hospital (P.T.); and Brain and Mind Centre (M.C.K.), University of Sydney and Institute of Clinical Neurosciences, Royal Prince Alfred Hospital, Sydney, Australia
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Kiernan MC, Ziemann U, Eisen A. Amyotrophic lateral sclerosis: Origins traced to impaired balance between neural excitation and inhibition in the neonatal period. Muscle Nerve 2019; 60:232-235. [PMID: 31233613 DOI: 10.1002/mus.26617] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 06/17/2019] [Accepted: 06/18/2019] [Indexed: 12/14/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is an adult onset disease but with an increasingly recognized preclinical prodrome. A wide spectrum of investigative approaches has identified loss of inhibitory function at the heart of ALS. In developing an explanation for the onset of ALS, it remains a consideration that ALS has its origins in neonatal derangement of the γ-aminobutyric acid (GABA)-ergic system, with delayed conversion from excitatory to mature inhibitory GABA and impaired excitation/inhibition balance. If this is so, the resulting chronic excitotoxicity could marginalize cortical network functioning very early in life, laying the path for neurodegeneration. The possibility that adult-onset neurodegenerative conditions might have their roots in early developmental derangements is worthy of consideration, particularly in relation to current models of disease pathogenesis. Unraveling the very early molecular events will be crucial in developing a better understanding of ALS and other adult neurodegenerative disorders. Muscle Nerve, 2019.
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Affiliation(s)
- Matthew C Kiernan
- The University of Sydney School of Medicine Brain and Mind Centre, Building F, Level 4, 94 Mallett Street, Camperdown, New South Wales, 2050, Australia
- Department of Neurology, Royal Prince Alfred Hospital, Sydney, Australia
| | - Ulf Ziemann
- Department of Neurology & Stroke, and Hertie-Institute for clinical brain research, University of Tübingen, Tübingen, Germany
| | - Andrew Eisen
- Division of Neurology (Emeritus), Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
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7
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Roux S, Lohof A, Ben-Ari Y, Poulain B, Bossu JL. Maturation of GABAergic Transmission in Cerebellar Purkinje Cells Is Sex Dependent and Altered in the Valproate Model of Autism. Front Cell Neurosci 2018; 12:232. [PMID: 30104962 PMCID: PMC6077203 DOI: 10.3389/fncel.2018.00232] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 07/16/2018] [Indexed: 12/20/2022] Open
Abstract
Brain development is accompanied by a shift in gamma-aminobutyric acid (GABA) response from depolarizing-excitatory to hyperpolarizing-inhibitory, due to a reduction of intracellular chloride concentration. This sequence is delayed in Autism Spectrum Disorders (ASD). We now report a similar alteration of this shift in the cerebellum, a structure implicated in ASD. Using single GABAA receptor channel recordings in cerebellar Purkinje cells (PCs), we found two conductance levels (18 and 10 pS), the former being dominant in newborns and the latter in young-adults. This conductance shift and the depolarizing/excitatory to hyperpolarizing/inhibitory GABA shift occurred 4 days later in females than males. Our data support a sex-dependent developmental shift of GABA conductance and chloride gradient, leading to different developmental timing in males and females. Because these developmental sequences are altered in ASD, this study further stresses the importance of developmental timing in pathological neurodevelopment.
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Affiliation(s)
- Sébastien Roux
- Institut des Neurosciences Cellulaires et Intégratives (INCI)-CNRS, UPR 3212, Strasbourg, France
| | - Ann Lohof
- Sorbonne Université, CNRS UMR 8256, Biological Adaptation and Ageing, Paris, France
| | - Yehezkel Ben-Ari
- Neurochlore, Ben-Ari Institute of Neuroarcheology, Campus Scientifique de Luminy, Aix Marseille Université, Marseille, France
| | - Bernard Poulain
- Institut des Neurosciences Cellulaires et Intégratives (INCI)-CNRS, UPR 3212, Strasbourg, France
| | - Jean-Louis Bossu
- Institut des Neurosciences Cellulaires et Intégratives (INCI)-CNRS, UPR 3212, Strasbourg, France
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8
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Bowerman M, Salsac C, Bernard V, Soulard C, Dionne A, Coque E, Benlefki S, Hince P, Dion PA, Butler-Browne G, Camu W, Bouchard JP, Delpire E, Rouleau GA, Raoul C, Scamps F. KCC3 loss-of-function contributes to Andermann syndrome by inducing activity-dependent neuromuscular junction defects. Neurobiol Dis 2017. [PMID: 28647557 DOI: 10.1016/j.nbd.2017.06.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Loss-of-function mutations in the potassium-chloride cotransporter KCC3 lead to Andermann syndrome, a severe sensorimotor neuropathy characterized by areflexia, amyotrophy and locomotor abnormalities. The molecular events responsible for axonal loss remain poorly understood. Here, we establish that global or neuron-specific KCC3 loss-of-function in mice leads to early neuromuscular junction (NMJ) abnormalities and muscular atrophy that are consistent with the pre-synaptic neurotransmission defects observed in patients. KCC3 depletion does not modify chloride handling, but promotes an abnormal electrical activity among primary motoneurons and mislocalization of Na+/K+-ATPase α1 in spinal cord motoneurons. Moreover, the activity-targeting drug carbamazepine restores Na+/K+-ATPase α1 localization and reduces NMJ denervation in Slc12a6-/- mice. We here propose that abnormal motoneuron electrical activity contributes to the peripheral neuropathy observed in Andermann syndrome.
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Affiliation(s)
- Melissa Bowerman
- The Institute for Neurosciences of Montpellier, Inserm UMR1051, Saint Eloi Hospital, Montpellier, France; Université Montpellier 1 & 2, Montpellier, France; University of Oxford, Department of Physiology, Anatomy and Genetics, Oxford, UK
| | - Céline Salsac
- The Institute for Neurosciences of Montpellier, Inserm UMR1051, Saint Eloi Hospital, Montpellier, France
| | - Véronique Bernard
- Université Pierre et Marie Curie UM CR 18, Paris, France; CNRS UMR8246, Paris, France; Inserm U1130, Paris, France
| | - Claire Soulard
- The Institute for Neurosciences of Montpellier, Inserm UMR1051, Saint Eloi Hospital, Montpellier, France; Université Montpellier 1 & 2, Montpellier, France
| | - Annie Dionne
- Université Laval, Québec, Canada; CHU de Québec, Hôpital de l'Enfant-Jésus, Département des sciences neurologiques, Québec, Québec, Canada
| | - Emmanuelle Coque
- The Institute for Neurosciences of Montpellier, Inserm UMR1051, Saint Eloi Hospital, Montpellier, France; Université Montpellier 1 & 2, Montpellier, France
| | - Salim Benlefki
- The Institute for Neurosciences of Montpellier, Inserm UMR1051, Saint Eloi Hospital, Montpellier, France; Université Montpellier 1 & 2, Montpellier, France
| | - Pascale Hince
- Montreal Neurological Institute and Hospital, Department of Neurology and Neurosurgery, McGill University, Montreal, Québec, Canada; Department of Pathology and Cellular Biology, Université de Montréal, Montréal, Québec, Canada
| | - Patrick A Dion
- Montreal Neurological Institute and Hospital, Department of Neurology and Neurosurgery, McGill University, Montreal, Québec, Canada; Department of Pathology and Cellular Biology, Université de Montréal, Montréal, Québec, Canada
| | - Gillian Butler-Browne
- UM76, Institut de Myologie, Université Pierre et Marie Curie, Paris, France; U974, Inserm, Paris, France; UMR7215, CNRS, GH Pitié Salpêtrière, Paris, France
| | - William Camu
- The Institute for Neurosciences of Montpellier, Inserm UMR1051, Saint Eloi Hospital, Montpellier, France; Department of Neurology, ALS Reference Center, Gui-de-Chauliac Hospital, Montpellier, France
| | - Jean-Pierre Bouchard
- Université Laval, Québec, Canada; CHU de Québec, Hôpital de l'Enfant-Jésus, Département des sciences neurologiques, Québec, Québec, Canada
| | - Eric Delpire
- Vanderbilt University Medical Center, Vanderbilt, USA
| | - Guy A Rouleau
- Montreal Neurological Institute and Hospital, Department of Neurology and Neurosurgery, McGill University, Montreal, Québec, Canada
| | - Cédric Raoul
- The Institute for Neurosciences of Montpellier, Inserm UMR1051, Saint Eloi Hospital, Montpellier, France; Université Montpellier 1 & 2, Montpellier, France
| | - Frédérique Scamps
- The Institute for Neurosciences of Montpellier, Inserm UMR1051, Saint Eloi Hospital, Montpellier, France; Université Montpellier 1 & 2, Montpellier, France.
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9
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Wang L, Jiang W, Lin Q, Zhang Y, Zhao C. DNA methylation regulatesgabrb2mRNA expression: developmental variations and disruptions inl-methionine-induced zebrafish with schizophrenia-like symptoms. GENES BRAIN AND BEHAVIOR 2016; 15:702-710. [DOI: 10.1111/gbb.12315] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 07/18/2016] [Accepted: 08/04/2016] [Indexed: 12/25/2022]
Affiliation(s)
- L. Wang
- Department of Medical Genetics, School of Basic Medical Sciences; Southern Medical University
- Guangdong Technology and Engineering Research Center for Molecular Diagnostics of Human Genetic Diseases
| | - W. Jiang
- Department of Medical Genetics, School of Basic Medical Sciences; Southern Medical University
- Guangdong Technology and Engineering Research Center for Molecular Diagnostics of Human Genetic Diseases
| | - Q. Lin
- Key Laboratory of Zebrafish Modeling and Drug Screening for Human Diseases of Guangdong Higher Education Institutes, Department of Developmental Biology, Institute of Genetic Engineering, School of Basic Medical Sciences; Southern Medical University; Guangzhou China
| | - Y. Zhang
- Key Laboratory of Zebrafish Modeling and Drug Screening for Human Diseases of Guangdong Higher Education Institutes, Department of Developmental Biology, Institute of Genetic Engineering, School of Basic Medical Sciences; Southern Medical University; Guangzhou China
| | - C. Zhao
- Department of Medical Genetics, School of Basic Medical Sciences; Southern Medical University
- Guangdong Technology and Engineering Research Center for Molecular Diagnostics of Human Genetic Diseases
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10
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Pohland M, Glumm J. Propriospinal interneurons in the spotlight for anatomical and functional recovery after spinal cord injury. Neural Regen Res 2016; 10:1737-8. [PMID: 26807097 PMCID: PMC4705774 DOI: 10.4103/1673-5374.170295] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Affiliation(s)
- Martin Pohland
- Institute of Cell Biology and Neurobiology, Center for Anatomy, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Jana Glumm
- Institute of Cell Biology and Neurobiology, Center for Anatomy, Charité-Universitätsmedizin Berlin, Berlin, Germany; Department of Neurosurgery, HELIOS Klinikum Berlin Buch, Berlin, Germany
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Emerging Roles of Filopodia and Dendritic Spines in Motoneuron Plasticity during Development and Disease. Neural Plast 2015; 2016:3423267. [PMID: 26843990 PMCID: PMC4710938 DOI: 10.1155/2016/3423267] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Revised: 09/10/2015] [Accepted: 09/21/2015] [Indexed: 01/16/2023] Open
Abstract
Motoneurons develop extensive dendritic trees for receiving excitatory and inhibitory synaptic inputs to perform a variety of complex motor tasks. At birth, the somatodendritic domains of mouse hypoglossal and lumbar motoneurons have dense filopodia and spines. Consistent with Vaughn's synaptotropic hypothesis, we propose a developmental unified-hybrid model implicating filopodia in motoneuron spinogenesis/synaptogenesis and dendritic growth and branching critical for circuit formation and synaptic plasticity at embryonic/prenatal/neonatal period. Filopodia density decreases and spine density initially increases until postnatal day 15 (P15) and then decreases by P30. Spine distribution shifts towards the distal dendrites, and spines become shorter (stubby), coinciding with decreases in frequency and increases in amplitude of excitatory postsynaptic currents with maturation. In transgenic mice, either overexpressing the mutated human Cu/Zn-superoxide dismutase (hSOD1G93A) gene or deficient in GABAergic/glycinergic synaptic transmission (gephyrin, GAD-67, or VGAT gene knockout), hypoglossal motoneurons develop excitatory glutamatergic synaptic hyperactivity. Functional synaptic hyperactivity is associated with increased dendritic growth, branching, and increased spine and filopodia density, involving actin-based cytoskeletal and structural remodelling. Energy-dependent ionic pumps that maintain intracellular sodium/calcium homeostasis are chronically challenged by activity and selectively overwhelmed by hyperactivity which eventually causes sustained membrane depolarization leading to excitotoxicity, activating microglia to phagocytose degenerating neurons under neuropathological conditions.
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12
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Eisen A, Kiernan M, Mitsumoto H, Swash M. Amyotrophic lateral sclerosis: a long preclinical period? J Neurol Neurosurg Psychiatry 2014; 85:1232-8. [PMID: 24648037 DOI: 10.1136/jnnp-2013-307135] [Citation(s) in RCA: 107] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The onset of amyotrophic lateral sclerosis (ALS) is conventionally considered as commencing with the recognition of clinical symptoms. We propose that, in common with other neurodegenerations, the pathogenic mechanisms culminating in ALS phenotypes begin much earlier in life. Animal models of genetically determined ALS exhibit pathological abnormalities long predating clinical deficits. The overt clinical ALS phenotype may develop when safety margins are exceeded subsequent to years of mitochondrial dysfunction, neuroinflammation or an imbalanced environment of excitation and inhibition in the neuropil. Somatic mutations, the epigenome and external environmental influences may interact to trigger a metabolic cascade that in the adult eventually exceeds functional threshold. A long preclinical and subsequent presymptomatic period pose a challenge for recognition, since it offers an opportunity for protective and perhaps even preventive therapeutic intervention to rescue dysfunctional neurons. We suggest, by analogy with other neurodegenerations and from SOD1 ALS mouse studies, that vulnerability might be induced in the perinatal period.
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Affiliation(s)
- Andrew Eisen
- Division of Neurology, University of British Columbia, Vancouver, British Columbia, Canada
| | | | - Hiroshi Mitsumoto
- Wesley J. Howe Professor of Neurology at CUMC, Eleanor and Lou Gehrig MDA/ALS Research Center, The Neurological Institute of New York, Columbia University Medical Center, New York, USA
| | - Michael Swash
- Queen Mary University of London, UK Institute of Neuroscience, University of Lisbon, Portugal
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13
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Fidelin K, Wyart C. Inhibition and motor control in the developing zebrafish spinal cord. Curr Opin Neurobiol 2014; 26:103-9. [DOI: 10.1016/j.conb.2013.12.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2013] [Revised: 12/13/2013] [Accepted: 12/21/2013] [Indexed: 01/07/2023]
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14
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Guérit S, Allain AE, Léon C, Cazenave W, Ferrara N, Branchereau P, Bikfalvi A. VEGF modulates synaptic activity in the developing spinal cord. Dev Neurobiol 2014; 74:1110-22. [DOI: 10.1002/dneu.22187] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Accepted: 04/25/2014] [Indexed: 01/31/2023]
Affiliation(s)
- Sylvaine Guérit
- Université Bordeaux; Angiogenesis and Tumor Microenvironment Laboratory; F-33615 Pessac Cedex France
- INSERM; Angiogenesis and Tumor Microenvironment Laboratory; F-33615 Pessac Cedex France
| | - Anne-Emilie Allain
- Université Bordeaux, Institut de Neurosciences Cognitives et Intégratives d'Aquitaine (INCIA), UMR 5287; F-33615 Pessac Cedex France
- CNRS; Institut de Neurosciences Cognitives et Intégratives d'Aquitaine (INCIA), UMR 5287; F-33615 Pessac Cedex France
| | - Céline Léon
- Université Bordeaux; Angiogenesis and Tumor Microenvironment Laboratory; F-33615 Pessac Cedex France
- INSERM; Angiogenesis and Tumor Microenvironment Laboratory; F-33615 Pessac Cedex France
| | - William Cazenave
- Université Bordeaux, Institut de Neurosciences Cognitives et Intégratives d'Aquitaine (INCIA), UMR 5287; F-33615 Pessac Cedex France
- CNRS; Institut de Neurosciences Cognitives et Intégratives d'Aquitaine (INCIA), UMR 5287; F-33615 Pessac Cedex France
| | | | - Pascal Branchereau
- Université Bordeaux, Institut de Neurosciences Cognitives et Intégratives d'Aquitaine (INCIA), UMR 5287; F-33615 Pessac Cedex France
- CNRS; Institut de Neurosciences Cognitives et Intégratives d'Aquitaine (INCIA), UMR 5287; F-33615 Pessac Cedex France
| | - Andréas Bikfalvi
- Université Bordeaux; Angiogenesis and Tumor Microenvironment Laboratory; F-33615 Pessac Cedex France
- INSERM; Angiogenesis and Tumor Microenvironment Laboratory; F-33615 Pessac Cedex France
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Woodrow L, Sheppard P, Gardiner P. Transcriptional changes in rat α-motoneurons resulting from increased physical activity. Neuroscience 2013; 255:45-54. [DOI: 10.1016/j.neuroscience.2013.09.038] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Revised: 09/12/2013] [Accepted: 09/13/2013] [Indexed: 11/26/2022]
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GABAergic neuron specification in the spinal cord, the cerebellum, and the cochlear nucleus. Neural Plast 2012; 2012:921732. [PMID: 22830054 PMCID: PMC3395262 DOI: 10.1155/2012/921732] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Revised: 05/17/2012] [Accepted: 05/17/2012] [Indexed: 12/01/2022] Open
Abstract
In the nervous system, there are a wide variety of neuronal cell types that have morphologically, physiologically, and histochemically different characteristics. These various types of neurons can be classified into two groups: excitatory and inhibitory neurons. The elaborate balance of the activities of the two types is very important to elicit higher brain function, because its imbalance may cause neurological disorders, such as epilepsy and hyperalgesia. In the central nervous system, inhibitory neurons are mainly represented by GABAergic ones with some exceptions such as glycinergic. Although the machinery to specify GABAergic neurons was first studied in the telencephalon, identification of key molecules, such as pancreatic transcription factor 1a (Ptf1a), as well as recently developed genetic lineage-tracing methods led to the better understanding of GABAergic specification in other brain regions, such as the spinal cord, the cerebellum, and the cochlear nucleus.
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Widespread structural and functional connectivity changes in amyotrophic lateral sclerosis: insights from advanced neuroimaging research. Neural Plast 2012; 2012:473538. [PMID: 22720174 PMCID: PMC3377360 DOI: 10.1155/2012/473538] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Revised: 04/20/2012] [Accepted: 04/23/2012] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a severe neurodegenerative disease principally affecting motor neurons. Besides motor symptoms, a subset of patients develop cognitive disturbances or even frontotemporal dementia (FTD), indicating that ALS may also involve extramotor brain regions. Both neuropathological and neuroimaging findings have provided further insight on the widespread effect of the neurodegeneration on brain connectivity and the underlying neurobiology of motor neurons degeneration. However, associated effects on motor and extramotor brain networks are largely unknown. Particularly, neuropathological findings suggest that ALS not only affects the frontotemporal network but rather is part of a wide clinicopathological spectrum of brain disorders known as TAR-DNA binding protein 43 (TDP-43) proteinopathies. This paper reviews the current state of knowledge concerning the neuropsychological and neuropathological sequelae of TDP-43 proteinopathies, with special focus on the neuroimaging findings associated with cognitive change in ALS.
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Inhibitory synaptic regulation of motoneurons: a new target of disease mechanisms in amyotrophic lateral sclerosis. Mol Neurobiol 2011; 45:30-42. [PMID: 22072396 DOI: 10.1007/s12035-011-8217-x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Accepted: 10/25/2011] [Indexed: 12/12/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is the third most common adult-onset neurodegenerative disease. It causes the degeneration of motoneurons and is fatal due to paralysis, particularly of respiratory muscles. ALS can be inherited, and specific disease-causing genes have been identified, but the mechanisms causing motoneuron death in ALS are not understood. No effective treatments exist for ALS. One well-studied theory of ALS pathogenesis involves faulty RNA editing and abnormal activation of specific glutamate receptors as well as failure of glutamate transport resulting in glutamate excitotoxicity; however, the excitotoxicity theory is challenged by the inability of anti-glutamate drugs to have major disease-modifying effects clinically. Nevertheless, hyperexcitability of upper and lower motoneurons is a feature of human ALS and transgenic (tg) mouse models of ALS. Motoneuron excitability is strongly modulated by synaptic inhibition mediated by presynaptic glycinergic and GABAergic innervations and postsynaptic glycine receptors (GlyR) and GABA(A) receptors; yet, the integrity of inhibitory systems regulating motoneurons has been understudied in experimental models, despite findings in human ALS suggesting that they may be affected. We have found in tg mice expressing a mutant form of human superoxide dismutase-1 (hSOD1) with a Gly93 → Ala substitution (G93A-hSOD1), causing familial ALS, that subsets of spinal interneurons degenerate. Inhibitory glycinergic innervation of spinal motoneurons becomes deficient before motoneuron degeneration is evident in G93A-hSOD1 mice. Motoneurons in these ALS mice also have insufficient synaptic inhibition as reflected by smaller GlyR currents, smaller GlyR clusters on their plasma membrane, and lower expression of GlyR1α mRNA compared to wild-type motoneurons. In contrast, GABAergic innervation of ALS mouse motoneurons and GABA(A) receptor function appear normal. Abnormal synaptic inhibition resulting from dysfunction of interneurons and motoneuron GlyRs is a new direction for unveiling mechanisms of ALS pathogenesis that could be relevant to new therapies for ALS.
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