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Dubey V, Roy A, Dixit AB, Tripathi M, Pandey S, Jain S, Chandra PS, Banerjee J. Dendritic reorganization in the hippocampus, anterior temporal lobe, and frontal neocortex of lithium-pilocarpine induced Status Epilepticus (SE). J Chem Neuroanat 2023; 133:102329. [PMID: 37659616 DOI: 10.1016/j.jchemneu.2023.102329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 08/19/2023] [Accepted: 08/29/2023] [Indexed: 09/04/2023]
Abstract
Status Epilepticus (SE) is a distributed network disorder, which involves the hippocampus and extra-hippocampal structures. Epileptogenesis in SE is tightly associated with neurogenesis, plastic changes and neural network reorganization facilitating hyper-excitability. On the other hand, dendritic spines are known to be the excitatory synapse in the brain. Therefore, dendritic spine dynamics could play an intricate role in these network alterations. However, the exact reason behind these structural changes in SE are elusive. In the present study, we have investigated the aforementioned hypothesis in the lithium-pilocarpine treated rat model of SE. We have examined cytoarchitectural and morphological changes using hematoxylin-eosin and Golgi-Cox staining in three different brain regions viz. CA1 pyramidal layer of the dorsal hippocampus, layer V pyramidal neurons of anterior temporal lobe (ATL), and frontal neocortex of the same animals. We observed macrostructural and layer-wise alteration of the pyramidal layer mainly in the hippocampus and ATL of SE rats, which is associated with sclerosis in the hippocampus. Sholl analysis exhibited partial dendritic plasticity in apical and basal dendrites of pyramidal cells as compared to the saline-treated weight-/age-matched control group. These findings indicate that region-specific alterations in dendritogenesis may contribute to the development of independent epileptogenic networks in the hippocampus, ATL, and frontal neocortex of SE rats.
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Affiliation(s)
- Vivek Dubey
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - Avishek Roy
- Department of Physiology, All India Institute of Medical Sciences, New Delhi, India
| | | | - Manjari Tripathi
- Department of Neurology, All India Institute of Medical Sciences, New Delhi, India
| | - Shivam Pandey
- Department of Biostatistics, All India Institute of Medical Sciences, New Delhi, India
| | - Suman Jain
- Department of Physiology, All India Institute of Medical Sciences, New Delhi, India
| | - P Sarat Chandra
- Department of Neurosurgery, All India Institute of Medical Sciences, New Delhi, India
| | - Jyotirmoy Banerjee
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India.
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2
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Righes Marafiga J, Calcagnotto ME. Electrophysiology of Dendritic Spines: Information Processing, Dynamic Compartmentalization, and Synaptic Plasticity. ADVANCES IN NEUROBIOLOGY 2023; 34:103-141. [PMID: 37962795 DOI: 10.1007/978-3-031-36159-3_3] [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: 11/15/2023]
Abstract
For many years, synaptic transmission was considered as information transfer between presynaptic neuron and postsynaptic cell. At the synaptic level, it was thought that dendritic arbors were only receiving and integrating all information flow sent along to the soma, while axons were primarily responsible for point-to-point information transfer. However, it is important to highlight that dendritic spines play a crucial role as postsynaptic components in central nervous system (CNS) synapses, not only integrating and filtering signals to the soma but also facilitating diverse connections with axons from many different sources. The majority of excitatory connections from presynaptic axonal terminals occurs on postsynaptic spines, although a subset of GABAergic synapses also targets spine heads. Several studies have shown the vast heterogeneous morphological, biochemical, and functional features of dendritic spines related to synaptic processing. In this chapter (adding to the relevant data on the biophysics of spines described in Chap. 1 of this book), we address the up-to-date functional dendritic characteristics assessed through electrophysiological approaches, including backpropagating action potentials (bAPs) and synaptic potentials mediated in dendritic and spine compartmentalization, as well as describing the temporal and spatial dynamics of glutamate receptors in the spines related to synaptic plasticity.
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Affiliation(s)
- Joseane Righes Marafiga
- Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, USA
| | - Maria Elisa Calcagnotto
- Department of Biochemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
- Graduate Program in Neuroscience, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
- Graduate Program in Biochemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
- Graduate Program in Psychiatry and Behavioral Science, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
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3
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Li C, Wu XJ, Li W. Neuropeptide S promotes maintenance of newly formed dendritic spines and performance improvement after motor learning in mice. Peptides 2022; 156:170860. [PMID: 35970276 DOI: 10.1016/j.peptides.2022.170860] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Revised: 06/18/2022] [Accepted: 08/10/2022] [Indexed: 10/15/2022]
Abstract
Neuropeptide S (NPS), an endogenous neuropeptide consisting of 20 amino acids, selectively binds and activates G protein-coupled receptor named neuropeptide S receptor (NPSR) to regulate a variety of physiological functions. NPS/NPSR system has been shown to play a pivotal role in regulating learning and memory in rodents. However, it remains unclear that how NPS/NPSR system affects neuronal functions and synaptic plasticity after learning. We found that intracerebroventricular (i.c.v.) injection of NPS promoted performance improvement and reduced sleep duration after motor learning, which could be blocked by pre-treatment with intraperitoneal (i.p.) injection of NPSR antagonist SHA 68. Using intravital two-photon imaging, we examined the effect of NPS on the postsynaptic dendritic spines of layer V pyramidal neurons in the mouse primary motor cortex after motor learning. We found that i.c.v. injection of NPS strengthened learning-induce new spines and facilitated their survival over time. Furthermore, i.c.v. injection of NPS increased calcium activity of apical dendrites and dendritic spines of layer V pyramidal neurons in the mouse primary motor cortex during the running period. These findings suggest that activation of NPSR by NPS increases synaptic calcium activity and learning-related synapse maintenance, thereby contributing to performance improvement after motor learning.
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Affiliation(s)
- Cong Li
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Shenzhen 518107, China
| | - Xu-Jun Wu
- Institute of Neurological and Psychiatric Disorders, Shenzhen Bay Laboratory, Shenzhen 518132, China
| | - Wei Li
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Shenzhen 518107, China; School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen 518055, China.
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4
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Seo SS, Louros SR, Anstey N, Gonzalez-Lozano MA, Harper CB, Verity NC, Dando O, Thomson SR, Darnell JC, Kind PC, Li KW, Osterweil EK. Excess ribosomal protein production unbalances translation in a model of Fragile X Syndrome. Nat Commun 2022; 13:3236. [PMID: 35688821 PMCID: PMC9187743 DOI: 10.1038/s41467-022-30979-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 05/23/2022] [Indexed: 12/21/2022] Open
Abstract
Dysregulated protein synthesis is a core pathogenic mechanism in Fragile X Syndrome (FX). The mGluR Theory of FX predicts that pathological synaptic changes arise from the excessive translation of mRNAs downstream of mGlu1/5 activation. Here, we use a combination of CA1 pyramidal neuron-specific TRAP-seq and proteomics to identify the overtranslating mRNAs supporting exaggerated mGlu1/5 -induced long-term synaptic depression (mGluR-LTD) in the FX mouse model (Fmr1−/y). Our results identify a significant increase in the translation of ribosomal proteins (RPs) upon mGlu1/5 stimulation that coincides with a reduced translation of long mRNAs encoding synaptic proteins. These changes are mimicked and occluded in Fmr1−/y neurons. Inhibiting RP translation significantly impairs mGluR-LTD and prevents the length-dependent shift in the translating population. Together, these results suggest that pathological changes in FX result from a length-dependent alteration in the translating population that is supported by excessive RP translation. Dysregulated protein synthesis is key contributor to Fragile X syndrome. Here the authors identify a relationship between ribosome expression and the translation of long mRNAs that contributes to synaptic weakening in a model of Fragile X syndrome.
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Affiliation(s)
- Sang S Seo
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.,Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, UK
| | - Susana R Louros
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.,Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, UK
| | - Natasha Anstey
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.,Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, UK
| | - Miguel A Gonzalez-Lozano
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Callista B Harper
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.,Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, UK
| | - Nicholas C Verity
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.,Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, UK
| | - Owen Dando
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.,Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, UK
| | - Sophie R Thomson
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.,Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, UK
| | - Jennifer C Darnell
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.,Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, UK
| | - Peter C Kind
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.,Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, UK
| | - Ka Wan Li
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Emily K Osterweil
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK. .,Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, UK.
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Structural Plasticity of the Hippocampus in Neurodegenerative Diseases. Int J Mol Sci 2022; 23:ijms23063349. [PMID: 35328770 PMCID: PMC8955928 DOI: 10.3390/ijms23063349] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 03/17/2022] [Accepted: 03/18/2022] [Indexed: 12/10/2022] Open
Abstract
Neuroplasticity is the capacity of neural networks in the brain to alter through development and rearrangement. It can be classified as structural and functional plasticity. The hippocampus is more susceptible to neuroplasticity as compared to other brain regions. Structural modifications in the hippocampus underpin several neurodegenerative diseases that exhibit cognitive and emotional dysregulation. This article reviews the findings of several preclinical and clinical studies about the role of structural plasticity in the hippocampus in neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, and multiple sclerosis. In this study, literature was surveyed using Google Scholar, PubMed, Web of Science, and Scopus, to review the mechanisms that underlie the alterations in the structural plasticity of the hippocampus in neurodegenerative diseases. This review summarizes the role of structural plasticity in the hippocampus for the etiopathogenesis of neurodegenerative diseases and identifies the current focus and gaps in knowledge about hippocampal dysfunctions. Ultimately, this information will be useful to propel future mechanistic and therapeutic research in neurodegenerative diseases.
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Mahalakshmi AM, Ray B, Tuladhar S, Hediyal TA, Raj P, Rathipriya AG, Qoronfleh MW, Essa MM, Chidambaram SB. Impact of Pharmacological and Non-Pharmacological Modulators on Dendritic Spines Structure and Functions in Brain. Cells 2021; 10:cells10123405. [PMID: 34943913 PMCID: PMC8699406 DOI: 10.3390/cells10123405] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 11/27/2021] [Accepted: 11/29/2021] [Indexed: 12/12/2022] Open
Abstract
Dendritic spines are small, thin, hair-like protrusions found on the dendritic processes of neurons. They serve as independent compartments providing large amplitudes of Ca2+ signals to achieve synaptic plasticity, provide sites for newer synapses, facilitate learning and memory. One of the common and severe complication of neurodegenerative disease is cognitive impairment, which is said to be closely associated with spine pathologies viz., decreased in spine density, spine length, spine volume, spine size etc. Many treatments targeting neurological diseases have shown to improve the spine structure and distribution. However, concise data on the various modulators of dendritic spines are imperative and a need of the hour. Hence, in this review we made an attempt to consolidate the effects of various pharmacological (cholinergic, glutamatergic, GABAergic, serotonergic, adrenergic, and dopaminergic agents) and non-pharmacological modulators (dietary interventions, enriched environment, yoga and meditation) on dendritic spines structure and functions. These data suggest that both the pharmacological and non-pharmacological modulators produced significant improvement in dendritic spine structure and functions and in turn reversing the pathologies underlying neurodegeneration. Intriguingly, the non-pharmacological approaches have shown to improve intellectual performances both in preclinical and clinical platforms, but still more technology-based evidence needs to be studied. Thus, we conclude that a combination of pharmacological and non-pharmacological intervention may restore cognitive performance synergistically via improving dendritic spine number and functions in various neurological disorders.
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Affiliation(s)
- Arehally M. Mahalakshmi
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India; (A.M.M.); (B.R.); (S.T.); (T.A.H.); (P.R.)
- SIG-Brain, Behaviour and Cognitive Neurosciences Research (BBRC), JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
| | - Bipul Ray
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India; (A.M.M.); (B.R.); (S.T.); (T.A.H.); (P.R.)
- Centre for Experimental Pharmacology and Toxicology, Central Animal Facility, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
| | - Sunanda Tuladhar
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India; (A.M.M.); (B.R.); (S.T.); (T.A.H.); (P.R.)
- Centre for Experimental Pharmacology and Toxicology, Central Animal Facility, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
| | - Tousif Ahmed Hediyal
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India; (A.M.M.); (B.R.); (S.T.); (T.A.H.); (P.R.)
- Centre for Experimental Pharmacology and Toxicology, Central Animal Facility, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
| | - Praveen Raj
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India; (A.M.M.); (B.R.); (S.T.); (T.A.H.); (P.R.)
| | | | - M. Walid Qoronfleh
- Q3CG Research Institute (QRI), Research and Policy Division, 7227 Rachel Drive, Ypsilanti, MI 48917, USA;
| | - Musthafa Mohamed Essa
- Department of Food Science and Nutrition, CAMS, Sultan Qaboos University, Muscat 123, Oman
- Ageing and Dementia Research Group, Sultan Qaboos University, Muscat 123, Oman
- Biomedical Sciences Department, University of Pacific, Sacramento, CA 95211, USA
- Correspondence: (M.M.E.); (S.B.C.)
| | - Saravana Babu Chidambaram
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India; (A.M.M.); (B.R.); (S.T.); (T.A.H.); (P.R.)
- SIG-Brain, Behaviour and Cognitive Neurosciences Research (BBRC), JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
- Centre for Experimental Pharmacology and Toxicology, Central Animal Facility, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
- Correspondence: (M.M.E.); (S.B.C.)
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7
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Nanoscale Sub-Compartmentalization of the Dendritic Spine Compartment. Biomolecules 2021; 11:biom11111697. [PMID: 34827695 PMCID: PMC8615865 DOI: 10.3390/biom11111697] [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: 10/21/2021] [Revised: 11/10/2021] [Accepted: 11/11/2021] [Indexed: 01/04/2023] Open
Abstract
Compartmentalization of the membrane is essential for cells to perform highly specific tasks and spatially constrained biochemical functions in topographically defined areas. These membrane lateral heterogeneities range from nanoscopic dimensions, often involving only a few molecular constituents, to micron-sized mesoscopic domains resulting from the coalescence of nanodomains. Short-lived domains lasting for a few milliseconds coexist with more stable platforms lasting from minutes to days. This panoply of lateral domains subserves the great variety of demands of cell physiology, particularly high for those implicated in signaling. The dendritic spine, a subcellular structure of neurons at the receiving (postsynaptic) end of central nervous system excitatory synapses, exploits this compartmentalization principle. In its most frequent adult morphology, the mushroom-shaped spine harbors neurotransmitter receptors, enzymes, and scaffolding proteins tightly packed in a volume of a few femtoliters. In addition to constituting a mesoscopic lateral heterogeneity of the dendritic arborization, the dendritic spine postsynaptic membrane is further compartmentalized into spatially delimited nanodomains that execute separate functions in the synapse. This review discusses the functional relevance of compartmentalization and nanodomain organization in synaptic transmission and plasticity and exemplifies the importance of this parcelization in various neurotransmitter signaling systems operating at dendritic spines, using two fast ligand-gated ionotropic receptors, the nicotinic acetylcholine receptor and the glutamatergic receptor, and a second-messenger G-protein coupled receptor, the cannabinoid receptor, as paradigmatic examples.
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8
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Vallés AS, Barrantes FJ. Dendritic spine membrane proteome and its alterations in autistic spectrum disorder. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2021; 128:435-474. [PMID: 35034726 DOI: 10.1016/bs.apcsb.2021.09.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Dendritic spines are small protrusions stemming from the dendritic shaft that constitute the primary specialization for receiving and processing excitatory neurotransmission in brain synapses. The disruption of dendritic spine function in several neurological and neuropsychiatric diseases leads to severe information-processing deficits with impairments in neuronal connectivity and plasticity. Spine dysregulation is usually accompanied by morphological alterations to spine shape, size and/or number that may occur at early pathophysiological stages and not necessarily be reflected in clinical manifestations. Autism spectrum disorder (ASD) is one such group of diseases involving changes in neuronal connectivity and abnormal morphology of dendritic spines on postsynaptic neurons. These alterations at the subcellular level correlate with molecular changes in the spine proteome, with alterations in the copy number, topography, or in severe cases in the phenotype of the molecular components, predominantly of those proteins involved in spine recognition and adhesion, reflected in abnormally short lifetimes of the synapse and compensatory increases in synaptic connections. Since cholinergic neurotransmission participates in the regulation of cognitive function (attention, memory, learning processes, cognitive flexibility, social interactions) brain acetylcholine receptors are likely to play an important role in the dysfunctional synapses in ASD, either directly or indirectly via the modulatory functions exerted on other neurotransmitter receptor proteins and spine-resident proteins.
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Affiliation(s)
- Ana Sofía Vallés
- Instituto de Investigaciones Bioquímicas de Bahía Blanca (UNS-CONICET), Bahía Blanca, Argentina
| | - Francisco J Barrantes
- Instituto de Investigaciones Biomédicas (BIOMED), UCA-CONICET, Buenos Aires, Argentina.
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9
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Urbano-Gámez JD, Casañas JJ, Benito I, Montesinos ML. Prenatal treatment with rapamycin restores enhanced hippocampal mGluR-LTD and mushroom spine size in a Down's syndrome mouse model. Mol Brain 2021; 14:84. [PMID: 34034796 PMCID: PMC8152312 DOI: 10.1186/s13041-021-00795-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 05/18/2021] [Indexed: 11/10/2022] Open
Abstract
Down syndrome (DS) is the most frequent genetic cause of intellectual disability including hippocampal-dependent memory deficits. We have previously reported hippocampal mTOR (mammalian target of rapamycin) hyperactivation, and related plasticity as well as memory deficits in Ts1Cje mice, a DS experimental model. Here we characterize the proteome of hippocampal synaptoneurosomes (SNs) from these mice, and found a predicted alteration of synaptic plasticity pathways, including long term depression (LTD). Accordingly, mGluR-LTD (metabotropic Glutamate Receptor-LTD) is enhanced in the hippocampus of Ts1Cje mice and this is correlated with an increased proportion of a particular category of mushroom spines in hippocampal pyramidal neurons. Remarkably, prenatal treatment of these mice with rapamycin has a positive pharmacological effect on both phenotypes, supporting the therapeutic potential of rapamycin/rapalogs for DS intellectual disability.
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Affiliation(s)
- Jesús David Urbano-Gámez
- Departamento de Fisiología Médica Y Biofísica, Universidad de Sevilla, Av. Sánchez-Pizjuán 4, 41009, Sevilla, Spain.,Instituto de Biomedicina de Sevilla, IBIS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain
| | - Juan José Casañas
- Departamento de Fisiología Médica Y Biofísica, Universidad de Sevilla, Av. Sánchez-Pizjuán 4, 41009, Sevilla, Spain.,Instituto de Biomedicina de Sevilla, IBIS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain
| | - Itziar Benito
- Departamento de Fisiología Médica Y Biofísica, Universidad de Sevilla, Av. Sánchez-Pizjuán 4, 41009, Sevilla, Spain.,Instituto de Biomedicina de Sevilla, IBIS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain.,Servicio de Animalario, Hospital Universitario Virgen Macarena (HUVM), 41009, Sevilla, Spain
| | - María Luz Montesinos
- Departamento de Fisiología Médica Y Biofísica, Universidad de Sevilla, Av. Sánchez-Pizjuán 4, 41009, Sevilla, Spain. .,Instituto de Biomedicina de Sevilla, IBIS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain.
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10
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Tellios V, Maksoud MJE, Xiang YY, Lu WY. Nitric Oxide Critically Regulates Purkinje Neuron Dendritic Development Through a Metabotropic Glutamate Receptor Type 1-Mediated Mechanism. THE CEREBELLUM 2021; 19:510-526. [PMID: 32270464 DOI: 10.1007/s12311-020-01125-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Nitric oxide (NO), specifically derived from neuronal nitric oxide synthase (nNOS), is a well-established regulator of synaptic transmission in Purkinje neurons (PNs), governing fundamental processes such as motor learning and coordination. Previous phenotypic analyses showed similar cerebellar structures between neuronal nitric oxide null (nNOS-/-) and wild-type (WT) adult male mice, despite prominent ataxic behavior within nNOS-/- mice. However, a study has yet to characterize PN molecular structure and their excitatory inputs during development in nNOS-/- mice. This study is the first to explore morphological abnormalities within the cerebellum of nNOS-/- mice, using immunohistochemistry and immunoblotting. This study sought to examine PN dendritic morphology and the expression of metabotropic glutamate receptor type 1 (mGluR1), vesicular glutamate transporter type 1 and 2 (vGluT1 and vGluT2), stromal interaction molecule 1 (STIM1), and calpain-1 within PNs of WT and nNOS-/- mice at postnatal day 7 (PD7), 2 weeks (2W), and 7 weeks (7W) of age. Results showed a decrease in PN dendritic branching at PD7 in nNOS-/- cerebella, while aberrant dendritic spine formation was noted in adult ages. Total protein expression of mGluR1 was decreased in nNOS-/- cerebella across development, while vGluT2, STIM1, and calpain-1 were significantly increased. Ex vivo treatment of WT slices with NOS inhibitor L-NAME increased calpain-1 expression, whereas treating nNOS-/- cerebellar slices with NO donor NOC-18 decreased calpain-1. Moreover, mGluR1 agonist DHPG increased calpain-1 in WT, but not in nNOS-/- slices. Together, these results indicate a novel role for nNOS/NO signaling in PN development, particularly by regulating an mGluR1-initiated calcium signaling mechanism.
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Affiliation(s)
- Vasiliki Tellios
- Graduate Program of Neuroscience, The University of Western Ontario, London, N6A 5B7, Canada.,Robarts Research Institute, London, N6A 5B7, Canada
| | - Matthew J E Maksoud
- Graduate Program of Neuroscience, The University of Western Ontario, London, N6A 5B7, Canada.,Robarts Research Institute, London, N6A 5B7, Canada
| | | | - Wei-Yang Lu
- Graduate Program of Neuroscience, The University of Western Ontario, London, N6A 5B7, Canada. .,Robarts Research Institute, London, N6A 5B7, Canada. .,Department of Physiology and Pharmacology, The University of Western Ontario, London, N6A 5B7, Canada.
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11
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Perea Vega ML, Sanchez MS, Fernández G, Paglini MG, Martin M, de Barioglio SR. Ghrelin treatment leads to dendritic spine remodeling in hippocampal neurons and increases the expression of specific BDNF-mRNA species. Neurobiol Learn Mem 2021; 179:107409. [PMID: 33609738 DOI: 10.1016/j.nlm.2021.107409] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 02/02/2021] [Accepted: 02/11/2021] [Indexed: 11/15/2022]
Abstract
Ghrelin (Gr) is an orexigenic peptide that acts via its specific receptor, GHSR-1a distributed throughout the brain, being mainly enriched in pituitary, cortex and hippocampus (Hp) modulating a variety of brain functions. Behavioral, electrophysiological and biochemical evidence indicated that Gr modulates the excitability and the synaptic plasticity in Hp. The present experiments were designed in order to extend the knowledge about the Gr effect upon structural synaptic plasticity since morphological and quantitative changes in spine density after Gr administration were analyzed "in vitro" and "in vivo". The results show that Gr administered to hippocampal cultures or stereotactically injected in vivo to Thy-1 mice increases the density of dendritic spines (DS) being the mushroom type highly increased in secondary and tertiary extensions. Spines classified as thin type were increased particularly in primary extensions. Furthermore, we show that Gr enhances selectively the expression of BDNF-mRNA species.
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Affiliation(s)
- M L Perea Vega
- Departamento de Farmacología, Instituto de Farmacología Experimental-IFEC-CONICET-Universidad Nacional de Córdoba, Argentina
| | - M S Sanchez
- Laboratorio de Neurobiología, Instituto de Investigación Médica Mercedes y Martín Ferreyra-INIMEC-CONICET-Universidad Nacional de Córdoba. Córdoba, Argentina; Instituto Universitario Ciencias Biomédicas Córdoba, Córdoba, Argentina
| | - G Fernández
- Laboratorio de Neurofisiología, Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - M G Paglini
- Laboratorio de Neurofisiología, Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - M Martin
- Laboratorio de Neurobiología, Instituto de Investigación Médica Mercedes y Martín Ferreyra-INIMEC-CONICET-Universidad Nacional de Córdoba. Córdoba, Argentina
| | - S R de Barioglio
- Departamento de Farmacología, Instituto de Farmacología Experimental-IFEC-CONICET-Universidad Nacional de Córdoba, Argentina.
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12
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Gross KS, Mermelstein PG. Estrogen receptor signaling through metabotropic glutamate receptors. VITAMINS AND HORMONES 2020; 114:211-232. [PMID: 32723544 DOI: 10.1016/bs.vh.2020.06.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
As the non-nuclear initiated effects of steroid hormone signaling have become more widely accepted, there has been a need to define the novel mechanisms of hormone receptor action that account for these outcomes. One mechanism that has emerged is the coupling of classical estrogen receptors (ERα and ERβ) with metabotropic glutamate receptors (mGluRs) to initiate G protein signaling cascades that ultimately influence neuronal physiology, structure, and behavior. Since its initial discovery in hippocampal neurons, evidence of ER/mGluR associations have been found throughout the nervous system, and the heterogeneity of possible receptor pairings afforded by multiple ER and mGluR subtypes appears to drive diverse molecular outcomes that can impact processes like cognition, motivation, movement, and pain. Recent evidence also suggests that the role of mGluRs in steroid hormone signaling may not be unique to ERs, but rather a conserved mechanism of membrane-initiated hormone receptor action.
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Affiliation(s)
- Kellie S Gross
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, United States
| | - Paul G Mermelstein
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, United States.
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13
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Lo LHY, Lai KO. Dysregulation of protein synthesis and dendritic spine morphogenesis in ASD: studies in human pluripotent stem cells. Mol Autism 2020; 11:40. [PMID: 32460854 PMCID: PMC7251853 DOI: 10.1186/s13229-020-00349-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Accepted: 05/11/2020] [Indexed: 12/18/2022] Open
Abstract
Autism spectrum disorder (ASD) is a brain disorder that involves changes in neuronal connections. Abnormal morphology of dendritic spines on postsynaptic neurons has been observed in ASD patients and transgenic mice that model different monogenetic causes of ASD. A number of ASD-associated genetic variants are known to disrupt dendritic local protein synthesis, which is essential for spine morphogenesis, synaptic transmission, and plasticity. Most of our understanding on the molecular mechanism underlying ASD depends on studies using rodents. However, recent advance in human pluripotent stem cells and their neural differentiation provides a powerful alternative tool to understand the cellular aspects of human neurological disorders. In this review, we summarize recent progress on studying mRNA targeting and local protein synthesis in stem cell-derived neurons, and discuss how perturbation of these processes may impact synapse development and functions that are relevant to cognitive deficits in ASD.
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Affiliation(s)
- Louisa Hoi-Ying Lo
- School of Biomedical Sciences, Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong, China
| | - Kwok-On Lai
- School of Biomedical Sciences, Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong, China. .,State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China.
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14
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Siri SO, Rozés-Salvador V, de la Villarmois EA, Ghersi MS, Quassollo G, Pérez MF, Conde C. Decrease of Rab11 prevents the correct dendritic arborization, synaptic plasticity and spatial memory formation. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1867:118735. [PMID: 32389643 DOI: 10.1016/j.bbamcr.2020.118735] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 04/27/2020] [Accepted: 05/02/2020] [Indexed: 12/30/2022]
Abstract
Emerging evidence shows that Rab11 recycling endosomes (REs Rab11) are essential for several neuronal processes, including the proper functioning of growth cones, synapse architecture regulation and neuronal migration. However, several aspects of REs Rab11 remain unclear, such as its sub-cellular distribution across neuronal development, contribution to dendritic tree organization and its consequences in memory formation. In this work we show a spatio-temporal correlation between the endogenous localization of REs Rab11 and developmental stage of neurons. Furthermore, Rab11-suppressed neurons showed an increase on dendritic branching (without altering total dendritic length) and misdistribution of dendritic proteins in cultured neurons. In addition, suppression of Rab11 in adult rat brains in vivo (by expressing shRab11 through lentiviral infection), showed a decrease on both the sensitivity to induce long-term potentiation and hippocampal-dependent memory acquisition. Taken together, our results suggest that REs Rab11 expression is required for a proper dendritic architecture and branching, controlling key aspects of synaptic plasticity and spatial memory formation.
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Affiliation(s)
- Sebastian O Siri
- Universidad Nacional de Córdoba (UNC), Av. Haya de la Torre s/n Ciudad Universitaria, 5000 Córdoba, Argentina; Instituto de Investigación Médica Mercedes y Martıín Ferreyra (INIMEC-CONICET-UNC), Av. Friuli 2434, 5016 Córdoba, Argentina
| | - Victoria Rozés-Salvador
- Universidad Nacional de Córdoba (UNC), Av. Haya de la Torre s/n Ciudad Universitaria, 5000 Córdoba, Argentina; Instituto A.P. de Ciencias Básicas y Aplicadas, Universidad Nacional de Villa María (UNVM), Arturo Jauretche 1555, Ciudad Universitaria, Villa María, Argentina
| | - Emilce Artur de la Villarmois
- IFEC, CONICET, Departamento de Farmacologia, Facultad de Ciencias Químicas, UNC, Haya de la Torre Y Medina Allende, 5000 Córdoba, Argentina
| | - Marisa S Ghersi
- IFEC, CONICET, Departamento de Farmacologia, Facultad de Ciencias Químicas, UNC, Haya de la Torre Y Medina Allende, 5000 Córdoba, Argentina
| | - Gonzalo Quassollo
- Universidad Nacional de Córdoba (UNC), Av. Haya de la Torre s/n Ciudad Universitaria, 5000 Córdoba, Argentina; Instituto de Investigación Médica Mercedes y Martıín Ferreyra (INIMEC-CONICET-UNC), Av. Friuli 2434, 5016 Córdoba, Argentina
| | - Mariela F Pérez
- IFEC, CONICET, Departamento de Farmacologia, Facultad de Ciencias Químicas, UNC, Haya de la Torre Y Medina Allende, 5000 Córdoba, Argentina
| | - Cecilia Conde
- Universidad Nacional de Córdoba (UNC), Av. Haya de la Torre s/n Ciudad Universitaria, 5000 Córdoba, Argentina; Instituto de Investigación Médica Mercedes y Martıín Ferreyra (INIMEC-CONICET-UNC), Av. Friuli 2434, 5016 Córdoba, Argentina.
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15
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Rantamäki T, Kohtala S. Encoding, Consolidation, and Renormalization in Depression: Synaptic Homeostasis, Plasticity, and Sleep Integrate Rapid Antidepressant Effects. Pharmacol Rev 2020; 72:439-465. [DOI: 10.1124/pr.119.018697] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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16
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Abstract
Fragile X syndrome (FXS) is a neurodevelopmental disorder that causes intellectual disability. It is a leading known genetic cause of autism. In addition to cognitive, social, and communication deficits, humans with FXS demonstrate abnormal sensory processing including sensory hypersensitivity. Sensory hypersensitivity commonly manifests as auditory, tactile, or visual defensiveness or avoidance. Clinical, behavioral, and electrophysiological studies consistently show auditory hypersensitivity, impaired habituation to repeated sounds, and reduced auditory attention in humans with FXS. Children with FXS also exhibit significant visuospatial impairments. Studies in infants and toddlers with FXS have documented impairments in processing texture-defined motion stimuli, temporal flicker, perceiving ordinal numerical sequence, and the ability to maintain the identity of dynamic object information during occlusion. Consistent with the observations in humans with FXS, fragile X mental retardation 1 ( Fmr1) gene knockout (KO) rodent models of FXS also show seizures, abnormal visual-evoked responses, auditory hypersensitivity, and abnormal processing at multiple levels of the auditory system, including altered acoustic startle responses. Among other sensory symptoms, individuals with FXS exhibit tactile defensiveness. Fmr1 KO mice also show impaired encoding of tactile stimulation frequency and larger size of receptive fields in the somatosensory cortex. Since sensory deficits are relatively more tractable from circuit mechanisms and developmental perspectives than more complex social behaviors, the focus of this review is on clinical, functional, and structural studies that outline the auditory, visual, and somatosensory processing deficits in FXS. The similarities in sensory phenotypes between humans with FXS and animal models suggest a likely conservation of basic sensory processing circuits across species and may provide a translational platform to not just develop biomarkers but also to understand underlying mechanisms. We argue that preclinical studies in animal models of FXS can facilitate the ongoing search for new therapeutic approaches in FXS by understanding mechanisms of basic sensory processing circuits and behaviors that are conserved across species.
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Affiliation(s)
- Maham Rais
- 1 Division of Biomedical Sciences, University of California Riverside School of Medicine, CA, USA.,2 Biomedical Sciences Graduate Program, University of California Riverside, CA, USA
| | - Devin K Binder
- 1 Division of Biomedical Sciences, University of California Riverside School of Medicine, CA, USA.,2 Biomedical Sciences Graduate Program, University of California Riverside, CA, USA.,3 Neuroscience Graduate Program, University of California Riverside, CA, USA
| | - Khaleel A Razak
- 2 Biomedical Sciences Graduate Program, University of California Riverside, CA, USA.,3 Neuroscience Graduate Program, University of California Riverside, CA, USA.,4 Psychology Department, University of California Riverside, CA, USA
| | - Iryna M Ethell
- 1 Division of Biomedical Sciences, University of California Riverside School of Medicine, CA, USA.,2 Biomedical Sciences Graduate Program, University of California Riverside, CA, USA.,3 Neuroscience Graduate Program, University of California Riverside, CA, USA
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17
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Czeredys M, Vigont VA, Boeva VA, Mikoshiba K, Kaznacheyeva EV, Kuznicki J. Huntingtin-Associated Protein 1A Regulates Store-Operated Calcium Entry in Medium Spiny Neurons From Transgenic YAC128 Mice, a Model of Huntington's Disease. Front Cell Neurosci 2018; 12:381. [PMID: 30455632 PMCID: PMC6231533 DOI: 10.3389/fncel.2018.00381] [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: 08/03/2018] [Accepted: 10/05/2018] [Indexed: 12/31/2022] Open
Abstract
Huntington's disease (HD) is a hereditary neurodegenerative disease that is caused by polyglutamine expansion within the huntingtin (HTT) gene. One of the cellular activities that is dysregulated in HD is store-operated calcium entry (SOCE), a process by which Ca2+ release from the endoplasmic reticulum (ER) induces Ca2+ influx from the extracellular space. HTT-associated protein-1 (HAP1) is a binding partner of HTT. The aim of the present study was to examine the role of HAP1A protein in regulating SOCE in YAC128 mice, a transgenic model of HD. After Ca2+ depletion from the ER by the activation of inositol-(1,4,5)triphosphate receptor type 1 (IP3R1), we detected an increase in the activity of SOC channels when HAP1 protein isoform HAP1A was overexpressed in medium spiny neurons (MSNs) from YAC128 mice. A decrease in the activity of SOC channels in YAC128 MSNs was observed when HAP1 protein was silenced. In YAC128 MSNs that overexpressed HAP1A, an increase in activity of IP3R1 was detected while the ionomycin-sensitive ER Ca2+ pool decreased. 6-Bromo-N-(2-phenylethyl)-2,3,4,9-tetrahydro-1H-carbazol-1-amine hydrochloride (C20H22BrClN2), identified in our previous studies as a SOCE inhibitor, restored the elevation of SOCE in YAC128 MSN cultures that overexpressed HAP1A. The IP3 sponge also restored the elevation of SOCE and increased the release of Ca2+ from the ER in YAC128 MSN cultures that overexpressed HAP1A. The overexpression of HAP1A in the human neuroblastoma cell line SK-N-SH (i.e., a cellular model of HD (SK-N-SH HTT138Q)) led to the appearance of a pool of constitutively active SOC channels and an increase in the expression of STIM2 protein. Our results showed that HAP1A causes the activation of SOC channels in HD models by affecting IP3R1 activity.
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Affiliation(s)
- Magdalena Czeredys
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology in Warsaw (IIMCB), Warsaw, Poland
| | - Vladimir A Vigont
- Institute of Cytology, Russian Academy of Sciences (RAS), St. Petersburg, Russia
| | - Vasilisa A Boeva
- Institute of Cytology, Russian Academy of Sciences (RAS), St. Petersburg, Russia
| | - Katsuhiko Mikoshiba
- Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute (BSI), Saitama, Japan
| | - Elena V Kaznacheyeva
- Institute of Cytology, Russian Academy of Sciences (RAS), St. Petersburg, Russia
| | - Jacek Kuznicki
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology in Warsaw (IIMCB), Warsaw, Poland
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18
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Tonn Eisinger KR, Gross KS, Head BP, Mermelstein PG. Interactions between estrogen receptors and metabotropic glutamate receptors and their impact on drug addiction in females. Horm Behav 2018; 104:130-137. [PMID: 29505763 PMCID: PMC6131090 DOI: 10.1016/j.yhbeh.2018.03.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 02/28/2018] [Accepted: 03/01/2018] [Indexed: 02/07/2023]
Abstract
Contribution to Special Issue on Fast effects of steroids. Estrogen receptors α and β (ERα and ERβ) have a unique relationship with metabotropic glutamate receptors (mGluRs) in the female rodent brain such that estradiol is able to recruit intracellular G-protein signaling cascades to influence neuronal physiology, structure, and ultimately behavior. While this association between ERs and mGluRs exists in many cell types and brain regions, its effects are perhaps most striking in the nucleus accumbens (NAc). This review will discuss the original characterization of ER/mGluR signaling and how estradiol activity in the NAc confers increased sensitivity to drugs of abuse in females through this mechanism.
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Affiliation(s)
- Katherine R Tonn Eisinger
- Department of Neuroscience and Graduate Program in Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
| | - Kellie S Gross
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA
| | - Brian P Head
- Department of Anesthesiology, University of California-San Diego, La Jolla, CA 92093, USA
| | - Paul G Mermelstein
- Department of Neuroscience and Graduate Program in Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA.
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19
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Beke A, Piko H, Haltrich I, Karcagi V, Rigo J, Molnar MJ, Fekete G. Study of patterns of inheritance of premature ovarian failure syndrome carrying maternal and paternal premutations. BMC MEDICAL GENETICS 2018; 19:113. [PMID: 29986653 PMCID: PMC6038184 DOI: 10.1186/s12881-018-0634-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 06/26/2018] [Indexed: 12/21/2022]
Abstract
BACKGROUND Premature ovarian failure / primary ovarian insufficiency (POF/POI) associated with the mutations of the FMR1 (Fragile-X Mental Retardation 1) gene belongs to the group of the so-called trinucleotide expansion diseases. Our aim was to analyse the relationship between the paternally inherited premutation (PIP) and the maternally inherited premutation (MIP) by the examination of the family members of women with POF, carrying the premutation allele confirmed by molecular genetic testing. METHODS Molecular genetic testing was performed in the patients of the 1st Department of Obstetrics and Gynecology with suspected premature ovarian failure. First we performed the southern blot analyses and for the certified premutation cases we used the Repeat Primed PCR. RESULTS Due to POF/POI, a total of 125 patients underwent genetic testing. The FMR1 gene trinucleotide repeat number was examined in the DNA samples of the patients, and in 15 cases (12%) deviations (CGG repeat number corresponding to premutation or gray zone) were detected. In 6 cases out of the 15 cases the CGG repeat number fell within the range of the so-called gray zone (41-54 CGG repeat) (4.8%, 6/125), and the FMR1 premutation (55-200 CGG repeat) ratio was 7.2% (9/125). In 4 out of the 15 cases we found differences in both alleles, one was a premutation allele, and the other allele showed a repeat number belonging to the gray zone. Out of 15 cases, only maternal inheritance (MIP) was detected in 2 cases, in one case the premutation allele (91 CGG repeat number), while in the other case an allele belonging to the gray zone (41 CGG repeat number) were inherited from their mothers. In 10 out of 15 cases, the patient inherited the premutation allele only from the father (PIP). In 5 out of the 10 cases (50%) the premutation allele was inherited from the father, and the repeat number ranged from 55 to 133. Out of 125 cases, 9 patients had detectable cytogenetic abnormalities (7.2%). CONCLUSIONS The RP-PCR method can be used to define the smaller premutations and the exact CGG number. Due to the quantitative nature of the RP-PCR, it is possible to detect the mosaicism as well.
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Affiliation(s)
- Artur Beke
- 1st Department of Obstetrics and Gynecology, Semmelweis University, Baross u. 27, Budapest, 1428, Hungary.
| | - Henriett Piko
- Institute of Genomic Medicine and Rare Disorders, Semmelweis University, Budapest, Hungary
| | - Iren Haltrich
- 2nd Department of Pediatrics, Semmelweis University fekete, Budapest, Hungary
| | - Veronika Karcagi
- Institute of Genomic Medicine and Rare Disorders, Semmelweis University, Budapest, Hungary
| | - Janos Rigo
- 1st Department of Obstetrics and Gynecology, Semmelweis University, Baross u. 27, Budapest, 1428, Hungary
| | - Maria Judit Molnar
- Institute of Genomic Medicine and Rare Disorders, Semmelweis University, Budapest, Hungary
| | - György Fekete
- 2nd Department of Pediatrics, Semmelweis University fekete, Budapest, Hungary
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20
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OCD-like behavior is caused by dysfunction of thalamo-amygdala circuits and upregulated TrkB/ERK-MAPK signaling as a result of SPRED2 deficiency. Mol Psychiatry 2018; 23:444-458. [PMID: 28070119 PMCID: PMC5794898 DOI: 10.1038/mp.2016.232] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 10/20/2016] [Accepted: 11/01/2016] [Indexed: 01/02/2023]
Abstract
Obsessive-compulsive disorder (OCD) is a common neuropsychiatric disease affecting about 2% of the general population. It is characterized by persistent intrusive thoughts and repetitive ritualized behaviors. While gene variations, malfunction of cortico-striato-thalamo-cortical (CSTC) circuits, and dysregulated synaptic transmission have been implicated in the pathogenesis of OCD, the underlying mechanisms remain largely unknown. Here we show that OCD-like behavior in mice is caused by deficiency of SPRED2, a protein expressed in various brain regions and a potent inhibitor of Ras/ERK-MAPK signaling. Excessive self-grooming, reflecting OCD-like behavior in rodents, resulted in facial skin lesions in SPRED2 knockout (KO) mice. This was alleviated by treatment with the selective serotonin reuptake inhibitor fluoxetine. In addition to the previously suggested involvement of cortico-striatal circuits, electrophysiological measurements revealed altered transmission at thalamo-amygdala synapses and morphological differences in lateral amygdala neurons of SPRED2 KO mice. Changes in synaptic function were accompanied by dysregulated expression of various pre- and postsynaptic proteins in the amygdala. This was a result of altered gene transcription and triggered upstream by upregulated tropomyosin receptor kinase B (TrkB)/ERK-MAPK signaling in the amygdala of SPRED2 KO mice. Pathway overactivation was mediated by increased activity of TrkB, Ras, and ERK as a specific result of SPRED2 deficiency and not elicited by elevated brain-derived neurotrophic factor levels. Using the MEK inhibitor selumetinib, we suppressed TrkB/ERK-MAPK pathway activity in vivo and reduced OCD-like grooming in SPRED2 KO mice. Altogether, this study identifies SPRED2 as a promising new regulator, TrkB/ERK-MAPK signaling as a novel mediating mechanism, and thalamo-amygdala synapses as critical circuitry involved in the pathogenesis of OCD.
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21
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Role of G Protein-Coupled Receptors in the Regulation of Structural Plasticity and Cognitive Function. Molecules 2017; 22:molecules22071239. [PMID: 28737723 PMCID: PMC6152405 DOI: 10.3390/molecules22071239] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 07/14/2017] [Indexed: 12/26/2022] Open
Abstract
Cognition and other higher brain functions are known to be intricately associated with the capacity of neural circuits to undergo structural reorganization. Structural remodelling of neural circuits, or structural plasticity, in the hippocampus plays a major role in learning and memory. Dynamic modifications of neuronal connectivity in the form of dendritic spine morphology alteration, as well as synapse formation and elimination, often result in the strengthening or weakening of specific neural circuits that determine synaptic plasticity. Changes in dendritic complexity and synapse number are mediated by cellular processes that are regulated by extracellular signals such as neurotransmitters and neurotrophic factors. As many neurotransmitters act on G protein-coupled receptors (GPCRs), it has become increasingly apparent that GPCRs can regulate structural plasticity through a myriad of G protein-dependent pathways and non-canonical signals. A thorough understanding of how GPCRs exert their regulatory influence on dendritic spine morphogenesis may provide new insights for treating cognitive impairment and decline in various age-related diseases. In this article, we review the evidence of GPCR-mediated regulation of structural plasticity, with a special emphasis on the involvement of common as well as distinct signalling pathways that are regulated by major neurotransmitters.
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22
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Incorrect dosage of IQSEC2, a known intellectual disability and epilepsy gene, disrupts dendritic spine morphogenesis. Transl Psychiatry 2017; 7:e1110. [PMID: 28463240 PMCID: PMC5534949 DOI: 10.1038/tp.2017.81] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 02/23/2017] [Indexed: 12/18/2022] Open
Abstract
There is considerable genetic and phenotypic heterogeneity associated with intellectual disability (ID), specific learning disabilities, attention-deficit hyperactivity disorder, autism and epilepsy. The intelligence quotient (IQ) motif and SEC7 domain containing protein 2 gene (IQSEC2) is located on the X-chromosome and harbors mutations that contribute to non-syndromic ID with and without early-onset seizure phenotypes in both sexes. Although IQ and Sec7 domain mutations lead to partial loss of IQSEC2 enzymatic activity, the in vivo pathogenesis resulting from these mutations is not known. Here we reveal that IQSEC2 has a key role in dendritic spine morphology. Partial loss-of-function mutations were modeled using a lentiviral short hairpin RNA (shRNA) approach, which achieved a 57% knockdown of Iqsec2 expression in primary hippocampal cell cultures from mice. Investigating gross morphological parameters after 8 days of in vitro culture (8DIV) identified a 32% reduction in primary axon length, in contrast to a 27% and 31% increase in the number and complexity of dendrites protruding from the cell body, respectively. This increase in dendritic complexity and spread was carried through dendritic spine development, with a 34% increase in the number of protrusions per dendritic segment compared with controls at 15DIV. Although the number of dendritic spines had normalized by 21DIV, a reduction was noted in the number of immature spines. In contrast, when modeling increased dosage, overexpression of wild-type IQSEC2 led to neurons with shorter axons that were more compact and displayed simpler dendritic branching. Disturbances to dendritic morphology due to knockdown of Iqsec2 were recapitulated in neurons from Iqsec2 knockout mice generated in our laboratory using CRISPR/Cas9 technology. These observations provide evidence of dosage sensitivity for IQSEC2, which normally escapes X-inactivation in females, and links these disturbances in expression to alterations in the morphology of developing neurons.
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23
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Franco LM, Okray Z, Linneweber GA, Hassan BA, Yaksi E. Reduced Lateral Inhibition Impairs Olfactory Computations and Behaviors in a Drosophila Model of Fragile X Syndrome. Curr Biol 2017; 27:1111-1123. [PMID: 28366741 PMCID: PMC5405172 DOI: 10.1016/j.cub.2017.02.065] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Revised: 02/02/2017] [Accepted: 02/28/2017] [Indexed: 01/02/2023]
Abstract
Fragile X syndrome (FXS) patients present neuronal alterations that lead to severe intellectual disability, but the underlying neuronal circuit mechanisms are poorly understood. An emerging hypothesis postulates that reduced GABAergic inhibition of excitatory neurons is a key component in the pathophysiology of FXS. Here, we directly test this idea in a FXS Drosophila model. We show that FXS flies exhibit strongly impaired olfactory behaviors. In line with this, olfactory representations are less odor specific due to broader response tuning of excitatory projection neurons. We find that impaired inhibitory interactions underlie reduced specificity in olfactory computations. Finally, we show that defective lateral inhibition across projection neurons is caused by weaker inhibition from GABAergic interneurons. We provide direct evidence that deficient inhibition impairs sensory computations and behavior in an in vivo model of FXS. Together with evidence of impaired inhibition in autism and Rett syndrome, these findings suggest a potentially general mechanism for intellectual disability. Lack of dFMRP leads to reduced olfactory attraction and aversion in fruit flies Odor selectivity of antennal lobe projection neurons is impaired in dfmr1− flies GABAergic lateral inhibition within the antennal lobe is weaker in dfmr1− flies Deficient lateral inhibition impairs sensory computations and animal behavior
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Affiliation(s)
- Luis M Franco
- Neuroelectronics Research Flanders (NERF), KU Leuven, Kapeldreef 75, 3001 Leuven, Belgium; VIB Center for the Biology of Disease, KU Leuven, Herestraat 49, 3000 Leuven, Belgium; Center for Human Genetics, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Zeynep Okray
- VIB Center for the Biology of Disease, KU Leuven, Herestraat 49, 3000 Leuven, Belgium; Center for Human Genetics, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Gerit A Linneweber
- VIB Center for the Biology of Disease, KU Leuven, Herestraat 49, 3000 Leuven, Belgium; Center for Human Genetics, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Bassem A Hassan
- VIB Center for the Biology of Disease, KU Leuven, Herestraat 49, 3000 Leuven, Belgium; Center for Human Genetics, KU Leuven, Herestraat 49, 3000 Leuven, Belgium; Institut du Cerveau et de la Moelle Epinière (ICM) - Hôpital Pitié-Salpêtrière, UPMC, Sorbonne Universités, Inserm, CNRS, 47 Boulevard Hôpital, 75013 Paris, France.
| | - Emre Yaksi
- Neuroelectronics Research Flanders (NERF), KU Leuven, Kapeldreef 75, 3001 Leuven, Belgium; Kavli Institute for Systems Neuroscience and Centre for Neural Computation, NTNU, Olav Kyrres gate 9, 7030 Trondheim, Norway.
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24
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Sethna F, Feng W, Ding Q, Robison AJ, Feng Y, Wang H. Enhanced expression of ADCY1 underlies aberrant neuronal signalling and behaviour in a syndromic autism model. Nat Commun 2017; 8:14359. [PMID: 28218269 PMCID: PMC5321753 DOI: 10.1038/ncomms14359] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 12/20/2016] [Indexed: 12/14/2022] Open
Abstract
Fragile X syndrome (FXS), caused by the loss of functional FMRP, is a leading cause of autism. Neurons lacking FMRP show aberrant mRNA translation and intracellular signalling. Here, we identify that, in Fmr1 knockout neurons, type 1 adenylyl cyclase (Adcy1) mRNA translation is enhanced, leading to excessive production of ADCY1 protein and insensitivity to neuronal stimulation. Genetic reduction of Adcy1 normalizes the aberrant ERK1/2- and PI3K-mediated signalling, attenuates excessive protein synthesis and corrects dendritic spine abnormality in Fmr1 knockout mice. Genetic reduction of Adcy1 also ameliorates autism-related symptoms including repetitive behaviour, defective social interaction and audiogenic seizures. Moreover, peripheral administration of NB001, an experimental compound that preferentially suppresses ADCY1 activity over other ADCY subtypes, attenuates the behavioural abnormalities in Fmr1 knockout mice. These results demonstrate a connection between the elevated Adcy1 translation and abnormal ERK1/2 signalling and behavioural symptoms in FXS. Fragile X syndrome (FXS) is a leading cause of autism and neurons lacking FMRP show aberrant mRNA translation and intracellular signalling. Here, the authors show that neurons from Fmr1 knockout mice have increased levels of ADCY1 protein, producing abnormal ERK1/2 signalling, dysregulated protein synthesis and behavioural symptoms associated with FXS.
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Affiliation(s)
- Ferzin Sethna
- Genetics Program, Michigan State University, East Lansing, Michigan 48824, USA
| | - Wei Feng
- Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia 30322, USA
| | - Qi Ding
- Department of Physiology, Michigan State University, East Lansing, Michigan 48824, USA
| | - Alfred J Robison
- Department of Physiology, Michigan State University, East Lansing, Michigan 48824, USA.,Neuroscience Program, Michigan State University, East Lansing, Michigan 48824, USA
| | - Yue Feng
- Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia 30322, USA
| | - Hongbing Wang
- Department of Physiology, Michigan State University, East Lansing, Michigan 48824, USA.,Neuroscience Program, Michigan State University, East Lansing, Michigan 48824, USA
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WAVE1 in neurons expressing the D1 dopamine receptor regulates cellular and behavioral actions of cocaine. Proc Natl Acad Sci U S A 2017; 114:1395-1400. [PMID: 28115704 DOI: 10.1073/pnas.1621185114] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Wiskott-Aldrich syndrome protein (WASP) family verprolin homologous protein 1 (WAVE1) regulates actin-related protein 2/3 (Arp2/3) complex-mediated actin polymerization. Our previous studies have found WAVE1 to be inhibited by Cdk5-mediated phosphorylation in brain and to play a role in the regulation of dendritic spine morphology. Here we report that mice in which WAVE1 was knocked out (KO) in neurons expressing the D1 dopamine receptor (D1-KO), but not mice where WAVE1 was knocked out in neurons expressing the D2 dopamine receptor (D2-KO), exhibited a significant decrease in place preference associated with cocaine. In contrast to wild-type (WT) and WAVE1 D2-KO mice, cocaine-induced sensitized locomotor behavior was not maintained in WAVE1 D1-KO mice. After chronic cocaine administration and following withdrawal, an acute cocaine challenge induced WAVE1 activation in striatum, which was assessed by dephosphorylation. The cocaine-induced WAVE1 dephosphorylation was attenuated by coadministration of either a D1 dopamine receptor or NMDA glutamate receptor antagonist. Upon an acute challenge of cocaine following chronic cocaine exposure and withdrawal, we also observed in WT, but not in WAVE1 D1-KO mice, a decrease in dendritic spine density and a decrease in the frequency of excitatory postsynaptic AMPA receptor currents in medium spiny projection neurons expressing the D1 dopamine receptor (D1-MSNs) in the nucleus accumbens. These results suggest that WAVE1 is involved selectively in D1-MSNs in cocaine-evoked neuronal activity-mediated feedback regulation of glutamatergic synapses.
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Zhang X, Hu M, Zhang L, An J, Yan W, Zhang Z, Liu J, Lu H, Chen X, Liu Y. MTEP impedes the neuronal polarization and the activity of the Akt-NF-κB pathway in rat hippocampal neurons. J Neurosci Res 2016; 95:1730-1744. [DOI: 10.1002/jnr.24002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 11/23/2016] [Accepted: 11/28/2016] [Indexed: 01/08/2023]
Affiliation(s)
- Xiaohua Zhang
- Institute of Neurobiology; Xi'an Jiaotong University Health Science Center; Xi'an Shaanxi People's Republic of China
| | - Ming Hu
- Department of Human Anatomy and Histoembryology, School of Basic Medical Science; Xi'an Jiaotong University; Xi'an Shaanxi People's Republic of China
| | - Lin Zhang
- Department of Neurology; Xi'an Center Hospital; Xi'an Shaanxi People's Republic of China
| | - Jing An
- Institute of Neurobiology; Xi'an Jiaotong University Health Science Center; Xi'an Shaanxi People's Republic of China
| | - Wenhui Yan
- Department of Pharmacology, School of Basic Medical Science; Xi'an Jiaotong University Health Science Center; Xi'an Shaanxi People's Republic of China
| | - Zhichao Zhang
- Institute of Neurobiology; Xi'an Jiaotong University Health Science Center; Xi'an Shaanxi People's Republic of China
| | - Jianxin Liu
- Institute of Neurobiology; Xi'an Jiaotong University Health Science Center; Xi'an Shaanxi People's Republic of China
| | - Haixia Lu
- Institute of Neurobiology; Xi'an Jiaotong University Health Science Center; Xi'an Shaanxi People's Republic of China
| | - Xinlin Chen
- Institute of Neurobiology; Xi'an Jiaotong University Health Science Center; Xi'an Shaanxi People's Republic of China
| | - Yong Liu
- Institute of Neurobiology; Xi'an Jiaotong University Health Science Center; Xi'an Shaanxi People's Republic of China
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FMRP regulates an ethanol-dependent shift in GABA BR function and expression with rapid antidepressant properties. Nat Commun 2016; 7:12867. [PMID: 27666021 PMCID: PMC5052688 DOI: 10.1038/ncomms12867] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 08/08/2016] [Indexed: 12/17/2022] Open
Abstract
Alcohol promotes lasting neuroadaptive changes that may provide relief from depressive symptoms, often referred to as the self-medication hypothesis. However, the molecular/synaptic pathways that are shared by alcohol and antidepressants are unknown. In the current study, acute exposure to ethanol produced lasting antidepressant and anxiolytic behaviours. To understand the functional basis of these behaviours, we examined a molecular pathway that is activated by rapid antidepressants. Ethanol, like rapid antidepressants, alters γ-aminobutyric acid type B receptor (GABABR) expression and signalling, to increase dendritic calcium. Furthermore, new GABABRs are synthesized in response to ethanol treatment, requiring fragile-X mental retardation protein (FMRP). Ethanol-dependent changes in GABABR expression, dendritic signalling, and antidepressant efficacy are absent in Fmr1-knockout (KO) mice. These findings indicate that FMRP is an important regulator of protein synthesis following alcohol exposure, providing a molecular basis for the antidepressant efficacy of acute ethanol exposure. Alcohol is thought to lead to neuroadaptive changes, although the underlying molecular mechanisms are unclear. Here, the authors find ethanol treatment alters GABAB-receptor expression via fragile-X mental retardation protein in mice, leading to antidepressant-like behaviours.
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Opposite Effects of mGluR1a and mGluR5 Activation on Nucleus Accumbens Medium Spiny Neuron Dendritic Spine Density. PLoS One 2016; 11:e0162755. [PMID: 27618534 PMCID: PMC5019418 DOI: 10.1371/journal.pone.0162755] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 08/26/2016] [Indexed: 11/19/2022] Open
Abstract
The group I metabotropic glutamate receptors (mGluR1a and mGluR5) are important modulators of neuronal structure and function. Although these receptors share common signaling pathways, they are capable of having distinct effects on cellular plasticity. We investigated the individual effects of mGluR1a or mGluR5 activation on dendritic spine density in medium spiny neurons in the nucleus accumbens (NAc), which has become relevant with the potential use of group I mGluR based therapeutics in the treatment of drug addiction. We found that systemic administration of mGluR subtype-specific positive allosteric modulators had opposite effects on dendritic spine densities. Specifically, mGluR5 positive modulation decreased dendritic spine densities in the NAc shell and core, but was without effect in the dorsal striatum, whereas increased spine densities in the NAc were observed with mGluR1a positive modulation. Additionally, direct activation of mGluR5 via CHPG administration into the NAc also decreased the density of dendritic spines. These data provide insight on the ability of group I mGluRs to induce structural plasticity in the NAc and demonstrate that the group I mGluRs are capable of producing not just distinct, but opposing, effects on dendritic spine density.
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29
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Tabet R, Vitale N, Moine H. Fragile X syndrome: Are signaling lipids the missing culprits? Biochimie 2016; 130:188-194. [PMID: 27597551 DOI: 10.1016/j.biochi.2016.09.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 09/01/2016] [Indexed: 10/21/2022]
Abstract
Fragile X syndrome (FXS) is the most common cause of inherited intellectual disability and autism. FXS results from the absence of FMRP, an RNA binding protein associated to ribosomes that influences the translation of specific mRNAs in post-synaptic compartments of neurons. The main molecular consequence of the absence of FMRP is an excessive translation of neuronal protein in several areas of the brain. This local protein synthesis deregulation is proposed to underlie the defect in synaptic plasticity responsible for FXS. Recent findings in neurons of the fragile X mouse model (Fmr1-KO) uncovered another consequence of the lack of FMRP: a deregulation of the diacylglycerol (DAG)/phosphatidic acid (PA) homeostasis. DAG and PA are two interconvertible lipids that influence membrane architecture and that act as essential signaling molecules that activate various downstream effectors, including master regulators of local protein synthesis and actin polymerization. As a consequence, DAG and PA govern a variety of cellular processes, including cell proliferation, vesicle/membrane trafficking and cytoskeletal organization. At the synapse, the level of these lipids is proposed to influence the synaptic activation status. FMRP appears as a master regulator of this neuronal process by controlling the translation of a diacylglycerol kinase enzyme that converts DAG into PA. The deregulated levels of DAG and PA caused by the absence of FMRP could represent a novel therapeutic target for the treatment of FXS.
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Affiliation(s)
- Ricardos Tabet
- Mass General Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Nicolas Vitale
- Institut des Neurosciences Cellulaires et Intégratives, UPR3212 CNRS, Université de Strasbourg, 67084 Strasbourg, France
| | - Hervé Moine
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, 67404 Illkirch, France; Centre National de la Recherche Scientifique, UMR7104, 67404 Illkirch, France; Institut National de la Santé et de la Recherche Médicale, U964, 67404 Illkirch, France; Université de Strasbourg, 67084 Strasbourg, France.
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Czeredys M, Maciag F, Methner A, Kuznicki J. Tetrahydrocarbazoles decrease elevated SOCE in medium spiny neurons from transgenic YAC128 mice, a model of Huntington's disease. Biochem Biophys Res Commun 2016; 483:1194-1205. [PMID: 27553284 DOI: 10.1016/j.bbrc.2016.08.106] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 08/08/2016] [Accepted: 08/18/2016] [Indexed: 10/21/2022]
Abstract
Huntington's disease (HD) is a hereditary neurodegenerative disease caused by a polyglutamine expansion within the huntingtin (HTT) gene. One of the cellular functions that is dysregulated in HD is store-operated calcium entry (SOCE), a process in which the depletion of Ca2+ from the endoplasmic reticulum (ER) induces Ca2+ influx from the extracellular space. We detected an enhanced activity of SOC channels in medium spiny neurons (MSNs) from YAC128 mice, a transgenic model of HD, and investigated whether this could be reverted by tetrahydrocarbazoles. The compound 6-bromo-N-(2-phenylethyl)-2,3,4,9-tetrahydro-1H-carbazol-1-amine hydrochloride was indeed able to restore the disturbed Ca2+ homeostasis and stabilize SOCE in YAC128 MSN cultures. We also detected a beneficial effect of this compound on the mitochondrial membrane potential. Since dysregulated Ca2+ homeostasis is believed to be one of the pathological hallmarks of HD, this compound might be a lead structure for HD treatment.
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Affiliation(s)
- Magdalena Czeredys
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology in Warsaw, Trojdena 4, 02-109, Warsaw, Poland.
| | - Filip Maciag
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology in Warsaw, Trojdena 4, 02-109, Warsaw, Poland
| | - Axel Methner
- Department of Neurology, University Medical Center and Focus Program Translational Neuroscience (FTN) of the Johannes Gutenberg-University Mainz, Langenbeckstr. 1, D-55131, Mainz, Germany
| | - Jacek Kuznicki
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology in Warsaw, Trojdena 4, 02-109, Warsaw, Poland
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31
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Jones OD. Do group I metabotropic glutamate receptors mediate LTD? Neurobiol Learn Mem 2016; 138:85-97. [PMID: 27545442 DOI: 10.1016/j.nlm.2016.08.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 08/01/2016] [Accepted: 08/17/2016] [Indexed: 01/31/2023]
Abstract
Synapses undergo significant structural and functional reorganization in response to varying patterns of stimulation. These forms of plasticity are considered fundamental to cognition and neuronal homeostasis. An increasing number of reports highlight the importance of activity-dependent synaptic strengthening (long term potentiation: LTP) for learning. However, the functional significance of activity-dependent weakening of synapses (long term depression: LTD) remains relatively poorly understood. One form of synaptic weakening, induced by group I metabotropic glutamate receptors (mGluRs), has received significant attention from a mechanistic point of view and because of its augmentation in a murine model of Fragile X Syndrome. Yet, studies of this form of plasticity often yield confusing, contradictory results. These conflicting findings are likely attributable to the bulk stimulation and recording techniques often used to study synaptic plasticity (typically involving evoked extracellular recordings, which represent the summed activity of many synapses). Such studies inherently blur the identity of the synapses undergoing change, thus giving the illusion that synapses per se are being modified when in fact this may only be true of a specific subset of synapses. Indeed, studies employing minimal synaptic activation paint a fundamentally different picture of what is commonly called "mGluR-LTD". Here, I review the evidence in favour of group I mGluRs as mediators of various forms of synaptic downregulation and attempt to explain discrepancies in the literature. I argue that, while multiple forms of synaptic weakening may be triggered by these receptors, the canonical form of group I mGluR-mediated depression, mGluR-LTD, is in fact not a depression of basal synaptic responses. Rather, it is a reversal of established LTP and thus a form of depotentiation. Far from being arbitrary, this distinction has significant implications for the role of group I mGluRs in cognition, both in the healthy brain and in pathological conditions. Further, the differential actions of group I mGluRs at naïve and potentiated synapses suggest these receptors signal in a state-dependent manner to regulate various stages of the learning process.
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Affiliation(s)
- Owen D Jones
- Department of Psychology, Brain Health Research Centre & Brain Research New Zealand, University of Otago, Dunedin, New Zealand.
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32
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Abbas AK. Protein Synthesis Inhibitors Did Not Interfere with Long-Term Depression Induced either Electrically in Juvenile Rats or Chemically in Middle-Aged Rats. PLoS One 2016; 11:e0161270. [PMID: 27517693 PMCID: PMC4982604 DOI: 10.1371/journal.pone.0161270] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 07/02/2016] [Indexed: 11/26/2022] Open
Abstract
In testing the hypothesis that long-term potentiation (LTP) maintenance depends on triggered protein synthesis, we found no effect of protein synthesis inhibitors (PSIs) on LTP stabilization. Similarly, some studies reported a lack of effect of PSIs on long-term depression (LTD); the lack of effect on LTD has been suggested to be resulting from the short time recordings. If this proposal were true, LTD might exhibit sensitivity to PSIs when the recording intervals were enough long. We firstly induced LTD by a standard protocol involving low frequency stimulation, which is suitable for eliciting NMDAR-LTD in CA1 area of hippocampal slices obtained from juvenile Sprague-Dawley rats. This LTD was persistent for intervals in range of 8–10 h. Treating slices with anisomycin, however, did not interfere with the magnitude and persistence of this form of LTD. The failure of anisomycin to block synaptic-LTD might be relied on the age of animal, the type of protein synthesis inhibitors and/or the inducing protocol. To verify whether those variables altogether were determinant, NMDA or DHPG was used to chemically elicit LTD recorded up to 10 h on hippocampal slices obtained from middle-aged rats. In either form of LTD, cycloheximide did not interfere with LTD stabilization. Furthermore, DHPG application did show an increase in the global protein synthesis as assayed by radiolabeled methodology indicating that though triggered protein synthesis can occur but not necessarily required for LTD expression. The findings confirm that stabilized LTD in either juvenile, or middle-aged rats can be independent of triggered protein synthesis. Although the processes responsible for the independence of LTD stabilization on the triggered protein synthesis are not yet defined, these findings raise the possibility that de novo protein synthesis is not universally necessary.
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Affiliation(s)
- Abdul-Karim Abbas
- Institute of Neuroscience and Physiology, University of Gothenburg, Box 432, SE-40530, Gothenburg, Sweden
- * E-mail:
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Suryavanshi PS, Gupta SC, Yadav R, Kesherwani V, Liu J, Dravid SM. Glutamate Delta-1 Receptor Regulates Metabotropic Glutamate Receptor 5 Signaling in the Hippocampus. Mol Pharmacol 2016; 90:96-105. [PMID: 27231330 DOI: 10.1124/mol.116.104786] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 05/24/2016] [Indexed: 11/22/2022] Open
Abstract
The delta family of ionotropic glutamate receptors consists of glutamate delta-1 (GluD1) and glutamate delta-2 receptors. We have previously shown that GluD1 knockout mice exhibit features of developmental delay, including impaired spine pruning and switch in the N-methyl-D-aspartate receptor subunit, which are relevant to autism and other neurodevelopmental disorders. Here, we identified a novel role of GluD1 in regulating metabotropic glutamate receptor 5 (mGlu5) signaling in the hippocampus. Immunohistochemical analysis demonstrated colocalization of mGlu5 with GluD1 punctas in the hippocampus. Additionally, GluD1 protein coimmunoprecipitated with mGlu5 in the hippocampal membrane fraction, as well as when overexpressed in human embryonic kidney 293 cells, demonstrating that GluD1 and mGlu5 may cooperate in a signaling complex. The interaction of mGlu5 with scaffold protein effector Homer, which regulates mechanistic target of rapamycin (mTOR) signaling, was abnormal both under basal conditions and in response to mGlu1/5 agonist (RS)-3,5-dihydroxyphenylglycine (DHPG) in GluD1 knockout mice. The basal levels of phosphorylated mTOR and protein kinase B, the signaling proteins downstream of mGlu5 activation, were higher in GluD1 knockout mice, and no further increase was induced by DHPG. We also observed higher basal protein translation and an absence of DHPG-induced increase in GluD1 knockout mice. In accordance with a role of mGlu5-mediated mTOR signaling in synaptic plasticity, DHPG-induced internalization of surface α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor subunits was impaired in the GluD1 knockout mice. These results demonstrate that GluD1 interacts with mGlu5, and loss of GluD1 impairs normal mGlu5 signaling potentially by dysregulating coupling to its effector. These studies identify a novel role of the enigmatic GluD1 subunit in hippocampal function.
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Affiliation(s)
| | - Subhash C Gupta
- Department of Pharmacology, Creighton University, Omaha, Nebraska
| | - Roopali Yadav
- Department of Pharmacology, Creighton University, Omaha, Nebraska
| | - Varun Kesherwani
- Department of Pharmacology, Creighton University, Omaha, Nebraska
| | - Jinxu Liu
- Department of Pharmacology, Creighton University, Omaha, Nebraska
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Sanderson TM, Hogg EL, Collingridge GL, Corrêa SAL. Hippocampal metabotropic glutamate receptor long-term depression in health and disease: focus on mitogen-activated protein kinase pathways. J Neurochem 2016; 139 Suppl 2:200-214. [PMID: 26923875 DOI: 10.1111/jnc.13592] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 02/16/2016] [Accepted: 02/21/2016] [Indexed: 12/16/2022]
Abstract
Group I metabotropic glutamate receptor (mGluR) dependent long-term depression (LTD) is a major form of synaptic plasticity underlying learning and memory. The molecular mechanisms involved in mGluR-LTD have been investigated intensively for the last two decades. In this 60th anniversary special issue article, we review the recent advances in determining the mechanisms that regulate the induction, transduction and expression of mGluR-LTD in the hippocampus, with a focus on the mitogen-activated protein kinase (MAPK) pathways. In particular we discuss the requirement of p38 MAPK and extracellular signal-regulated kinase 1/2 (ERK 1/2) activation. The recent advances in understanding the signaling cascades regulating mGluR-LTD are then related to the cognitive impairments observed in neurological disorders, such as fragile X syndrome and Alzheimer's disease. mGluR-LTD is a form of synaptic plasticity that impacts on memory formation. In the hippocampus mitogen-activated protein kinases (MAPKs) have been found to be important in mGluR-LTD. In this 60th anniversary special issue article, we review the independent and complementary roles of two classes of MAPK, p38 and ERK1/2 and link this to the aberrant mGluR-LTD that has an important role in diseases. This article is part of the 60th Anniversary special issue.
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Affiliation(s)
- Thomas M Sanderson
- Centre for Synaptic Plasticity, School of Physiology, Pharmacology & Neuroscience, University of Bristol, Bristol, UK
| | - Ellen L Hogg
- Bradford School of Pharmacy, Faculty of Life Sciences, University of Bradford, Bradford, UK
| | - Graham L Collingridge
- Centre for Synaptic Plasticity, School of Physiology, Pharmacology & Neuroscience, University of Bristol, Bristol, UK. .,Department of Physiology, University of Toronto, Toronto, Ontario, Canada. .,Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada.
| | - Sonia A L Corrêa
- Bradford School of Pharmacy, Faculty of Life Sciences, University of Bradford, Bradford, UK.
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LaCrosse AL, Taylor SB, Nemirovsky NE, Gass JT, Olive MF. mGluR5 Positive and Negative Allosteric Modulators Differentially Affect Dendritic Spine Density and Morphology in the Prefrontal Cortex. CNS & NEUROLOGICAL DISORDERS-DRUG TARGETS 2016; 14:476-85. [PMID: 25921744 DOI: 10.2174/1871527314666150429112849] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 01/17/2015] [Accepted: 01/19/2015] [Indexed: 12/31/2022]
Abstract
Positive and negative allosteric modulators (PAMs and NAMs, respectively) of type 5 metabotropic glutamate receptors (mGluR5) are currently being investigated as novel treatments for neuropsychiatric diseases including drug addiction, schizophrenia, and Fragile X syndrome. However, only a handful of studies have examined the effects of mGluR5 PAMs or NAMs on the structural plasticity of dendritic spines in otherwise naïve animals, particularly in brain regions mediating executive function. In the present study, we assessed dendritic spine density and morphology in pyramidal cells of the medial prefrontal cortex (mPFC) after repeated administration of either the prototypical mGluR5 PAM 3-cyano-N-(1,3-diphenyl-1H-pyrazol-5- yl)benzamide (CDPPB, 20 mg/kg), the clinically utilized mGluR5 NAM 1-(3-chlorophenyl)-3-(3-methyl-5-oxo-4Himidazol- 2-yl)urea (fenobam, 20 mg/kg), or vehicle in male Sprague-Dawley rats. Following once daily treatment for 10 consecutive days, coronal brain sections containing the mPFC underwent diolistic labeling and 3D image analysis of dendritic spines. Compared to vehicle treated animals, rats administered fenobam exhibited significant increases in dendritic spine density and the overall frequency of spines with small (<0.2 μm) head diameters, decreases in frequency of spines with medium (0.2-0.4 μm) head diameters, and had no changes in frequency of spines with large head diameters (>0.4 μm). Administration of CDPPB had no discernable effects on dendritic spine density or morphology, and neither CDPPB nor fenobam had any effect on spine length or volume. We conclude that mGluR5 PAMs and NAMs differentially affect mPFC dendritic spine structural plasticity in otherwise naïve animals, and additional studies assessing their effects in combination with cognitive or behavioral tasks are needed.
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Affiliation(s)
| | | | | | | | - Michael F Olive
- Department of Psychology, Arizona State University, PO Box 871104, Tempe, AZ 85287, USA.
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Johnson-Venkatesh EM, Khan MN, Murphy GG, Sutton MA, Umemori H. Excitability governs neural development in a hippocampal region-specific manner. Development 2015; 142:3879-91. [PMID: 26417041 DOI: 10.1242/dev.121202] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 09/10/2015] [Indexed: 01/23/2023]
Abstract
Neuronal activity, including intrinsic neuronal excitability and synaptic transmission, is an essential regulator of brain development. However, how the intrinsic neuronal excitability of distinct neurons affects their integration into developing circuits remains poorly understood. To investigate this problem, we created several transgenic mouse lines in which intrinsic excitability is suppressed, and the neurons are effectively silenced, in different excitatory neuronal populations of the hippocampus. Here we show that CA1, CA3 and dentate gyrus neurons each have unique responses to suppressed intrinsic excitability during circuit development. Silenced CA1 pyramidal neurons show altered spine development and synaptic transmission after postnatal day 15. By contrast, silenced CA3 pyramidal neurons seem to develop normally. Silenced dentate granule cells develop with input-specific decreases in spine density starting at postnatal day 11; however, a compensatory enhancement of neurotransmitter release onto these neurons maintains normal levels of synaptic activity. The synaptic changes in CA1 and dentate granule neurons are not observed when synaptic transmission, rather than intrinsic excitability, is blocked in these neurons. Thus, our results demonstrate a crucial role for intrinsic neuronal excitability in establishing hippocampal connectivity and reveal that neuronal development in each hippocampal region is distinctly regulated by excitability.
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Affiliation(s)
- Erin M Johnson-Venkatesh
- Department of Neurology, F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA Molecular & Behavioral Neuroscience Institute, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Mudassar N Khan
- Molecular & Behavioral Neuroscience Institute, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Geoffrey G Murphy
- Molecular & Behavioral Neuroscience Institute, University of Michigan Medical School, Ann Arbor, MI 48109, USA Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Michael A Sutton
- Molecular & Behavioral Neuroscience Institute, University of Michigan Medical School, Ann Arbor, MI 48109, USA Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Hisashi Umemori
- Department of Neurology, F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA Molecular & Behavioral Neuroscience Institute, University of Michigan Medical School, Ann Arbor, MI 48109, USA Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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Lyons JI, Kerr GR, Mueller PW. Fragile X Syndrome: Scientific Background and Screening Technologies. J Mol Diagn 2015; 17:463-71. [PMID: 26162330 DOI: 10.1016/j.jmoldx.2015.04.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 03/05/2015] [Accepted: 04/02/2015] [Indexed: 11/26/2022] Open
Abstract
Fragile X is the most common inherited cause of mental retardation with a prevalence of 1 in 4000 for males and 1 in 5000 to 8000 for females. The American College of Medical Genetics and Genomics has recommended diagnostic testing for fragile X in symptomatic persons, women with ovarian dysfunction, and persons with tremor/ataxia syndrome. Although medical and scientific professionals do not currently recommend screening nonsymptomatic populations, improvements in current treatment approaches and ongoing clinical trials have generated growing interest in screening for fragile X. Here, we briefly review the relevant molecular basis of fragile X and fragile X testing and compare three different molecular technologies available for fragile X screening in both males and females. These technologic approaches include destabilizing the CGG-repeat region with betaine and using chimeric CGG-targeted PCR primers, using heat pulses to destabilize C-G bonds in the PCR extension step, and using melting curve analysis to differentiate expanded CGG repeats from normals. The first two-step method performed with high sensitivity and specificity. The second method provided agarose gel images that allow identification of males with expanded CGG repeats and females with expanded CGG-repeat bands which are sometimes faint. The third melting curve analysis method would require controls in each run to correct for shifting optimal cutoff values.
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Affiliation(s)
- Justine I Lyons
- Molecular Risk Assessment Laboratory, Newborn Screening and Molecular Biology Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Gregory R Kerr
- Molecular Risk Assessment Laboratory, Newborn Screening and Molecular Biology Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Patricia W Mueller
- Molecular Risk Assessment Laboratory, Newborn Screening and Molecular Biology Branch, Centers for Disease Control and Prevention, Atlanta, Georgia.
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38
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The ROR2 tyrosine kinase receptor regulates dendritic spine morphogenesis in hippocampal neurons. Mol Cell Neurosci 2015; 67:22-30. [DOI: 10.1016/j.mcn.2015.05.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 05/03/2015] [Accepted: 05/19/2015] [Indexed: 11/19/2022] Open
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Kalinowska M, Chávez AE, Lutzu S, Castillo PE, Bukauskas FF, Francesconi A. Actinin-4 Governs Dendritic Spine Dynamics and Promotes Their Remodeling by Metabotropic Glutamate Receptors. J Biol Chem 2015; 290:15909-20. [PMID: 25944910 DOI: 10.1074/jbc.m115.640136] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Indexed: 11/06/2022] Open
Abstract
Dendritic spines are dynamic, actin-rich protrusions in neurons that undergo remodeling during neuronal development and activity-dependent plasticity within the central nervous system. Although group 1 metabotropic glutamate receptors (mGluRs) are critical for spine remodeling under physiopathological conditions, the molecular components linking receptor activity to structural plasticity remain unknown. Here we identify a Ca(2+)-sensitive actin-binding protein, α-actinin-4, as a novel group 1 mGluR-interacting partner that orchestrates spine dynamics and morphogenesis in primary neurons. Functional silencing of α-actinin-4 abolished spine elongation and turnover stimulated by group 1 mGluRs despite intact surface receptor expression and downstream ERK1/2 signaling. This function of α-actinin-4 in spine dynamics was underscored by gain-of-function phenotypes in untreated neurons. Here α-actinin-4 induced spine head enlargement, a morphological change requiring the C-terminal domain of α-actinin-4 that binds to CaMKII, an interaction we showed to be regulated by group 1 mGluR activation. Our data provide mechanistic insights into spine remodeling by metabotropic signaling and identify α-actinin-4 as a critical effector of structural plasticity within neurons.
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Affiliation(s)
- Magdalena Kalinowska
- From the Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Andrés E Chávez
- From the Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Stefano Lutzu
- From the Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Pablo E Castillo
- From the Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Feliksas F Bukauskas
- From the Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Anna Francesconi
- From the Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York 10461
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Bird CW, Candelaria-Cook FT, Magcalas CM, Davies S, Valenzuela CF, Savage DD, Hamilton DA. Moderate prenatal alcohol exposure enhances GluN2B containing NMDA receptor binding and ifenprodil sensitivity in rat agranular insular cortex. PLoS One 2015; 10:e0118721. [PMID: 25747876 PMCID: PMC4351952 DOI: 10.1371/journal.pone.0118721] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Accepted: 01/06/2015] [Indexed: 12/31/2022] Open
Abstract
Prenatal exposure to alcohol affects the expression and function of glutamatergic neurotransmitter receptors in diverse brain regions. The present study was undertaken to fill a current gap in knowledge regarding the regional specificity of ethanol-related alterations in glutamatergic receptors in the frontal cortex. We quantified subregional expression and function of glutamatergic neurotransmitter receptors (AMPARs, NMDARs, GluN2B-containing NMDARs, mGluR1s, and mGluR5s) by radioligand binding in the agranular insular cortex (AID), lateral orbital area (LO), prelimbic cortex (PrL) and primary motor cortex (M1) of adult rats exposed to moderate levels of ethanol during prenatal development. Increased expression of GluN2B-containing NMDARs was observed in AID of ethanol-exposed rats compared to modest reductions in other regions. We subsequently performed slice electrophysiology measurements in a whole-cell patch-clamp preparation to quantify the sensitivity of evoked NMDAR-mediated excitatory postsynaptic currents (EPSCs) in layer II/III pyramidal neurons of AID to the GluN2B negative allosteric modulator ifenprodil. Consistent with increased GluN2B expression, ifenprodil caused a greater reduction in NMDAR-mediated EPSCs from prenatal alcohol-exposed rats than saccharin-exposed control animals. No alterations in AMPAR-mediated EPSCs or the ratio of AMPARs/NMDARs were observed. Together, these data indicate that moderate prenatal alcohol exposure has a significant and lasting impact on GluN2B-containing receptors in AID, which could help to explain ethanol-related alterations in learning and behaviors that depend on this region.
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Affiliation(s)
- Clark W. Bird
- Department of Psychology, University of New Mexico, Albuquerque, New Mexico, United States of America
| | | | - Christy M. Magcalas
- Department of Psychology, University of New Mexico, Albuquerque, New Mexico, United States of America
| | - Suzy Davies
- Department of Neurosciences, University of New Mexico, Albuquerque, New Mexico, United States of America
| | - C. Fernando Valenzuela
- Department of Neurosciences, University of New Mexico, Albuquerque, New Mexico, United States of America
| | - Daniel D. Savage
- Department of Neurosciences, University of New Mexico, Albuquerque, New Mexico, United States of America
| | - Derek A. Hamilton
- Department of Psychology, University of New Mexico, Albuquerque, New Mexico, United States of America
- Department of Neurosciences, University of New Mexico, Albuquerque, New Mexico, United States of America
- * E-mail:
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Han K, Chen H, Gennarino VA, Richman R, Lu HC, Zoghbi HY. Fragile X-like behaviors and abnormal cortical dendritic spines in cytoplasmic FMR1-interacting protein 2-mutant mice. Hum Mol Genet 2014; 24:1813-23. [PMID: 25432536 DOI: 10.1093/hmg/ddu595] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Silencing of fragile X mental retardation 1 (FMR1) gene and loss of fragile X mental retardation protein (FMRP) cause fragile X syndrome (FXS), a genetic disorder characterized by intellectual disability and autistic behaviors. FMRP is an mRNA-binding protein regulating neuronal translation of target mRNAs. Abnormalities in actin-rich dendritic spines are major neuronal features in FXS, but the molecular mechanism and identity of FMRP targets mediating this phenotype remain largely unknown. Cytoplasmic FMR1-interacting protein 2 (Cyfip2) was identified as an interactor of FMRP, and its mRNA is a highly ranked FMRP target in mouse brain. Importantly, Cyfip2 is a component of WAVE regulatory complex, a key regulator of actin cytoskeleton, suggesting that Cyfip2 could be implicated in the dendritic spine phenotype of FXS. Here, we generated and characterized Cyfip2-mutant (Cyfip2(+/-)) mice. We found that Cyfip2(+/-) mice exhibited behavioral phenotypes similar to Fmr1-null (Fmr1(-/y)) mice, an animal model of FXS. Synaptic plasticity and dendritic spines were normal in Cyfip2(+/-) hippocampus. However, dendritic spines were altered in Cyfip2(+/-) cortex, and the dendritic spine phenotype of Fmr1(-/y) cortex was aggravated in Fmr1(-/y); Cyfip2(+/-) double-mutant mice. In addition to the spine changes at basal state, metabotropic glutamate receptor (mGluR)-induced dendritic spine regulation was impaired in both Fmr1(-/y) and Cyfip2(+/-) cortical neurons. Mechanistically, mGluR activation induced mRNA translation-dependent increase of Cyfip2 in wild-type cortical neurons, but not in Fmr1(-/y) or Cyfip2(+/-) neurons. These results suggest that misregulation of Cyfip2 function and its mGluR-induced expression contribute to the neurobehavioral phenotypes of FXS.
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Affiliation(s)
- Kihoon Han
- Department of Molecular and Human Genetics, The Howard Hughes Medical Institute, Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Hogmei Chen
- Departments of Pediatrics and, The Cain Foundation Laboratories Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Vincenzo A Gennarino
- Department of Molecular and Human Genetics, Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Ronald Richman
- Department of Molecular and Human Genetics, The Howard Hughes Medical Institute, Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Hui-Chen Lu
- Departments of Pediatrics and, Program in Developmental Biology and Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA, The Cain Foundation Laboratories Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Huda Y Zoghbi
- Department of Molecular and Human Genetics, The Howard Hughes Medical Institute, Departments of Pediatrics and, Program in Developmental Biology and Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA, Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
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Abstract
The RNA-binding protein fused-in-sarcoma (FUS) has been associated with amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD), two neurodegenerative disorders that share similar clinical and pathological features. Both missense mutations and overexpression of wild-type FUS protein can be pathogenic in human patients. To study the molecular and cellular basis by which FUS mutations and overexpression cause disease, we generated novel transgenic mice globally expressing low levels of human wild-type protein (FUS(WT)) and a pathological mutation (FUS(R521G)). FUS(WT) and FUS(R521G) mice that develop severe motor deficits also show neuroinflammation, denervated neuromuscular junctions, and premature death, phenocopying the human diseases. A portion of FUS(R521G) mice escape early lethality; these escapers have modest motor impairments and altered sociability, which correspond with a reduction of dendritic arbors and mature spines. Remarkably, only FUS(R521G) mice show dendritic defects; FUS(WT) mice do not. Activation of metabotropic glutamate receptors 1/5 in neocortical slices and isolated synaptoneurosomes increases endogenous mouse FUS and FUS(WT) protein levels but decreases the FUS(R521G) protein, providing a potential biochemical basis for the dendritic spine differences between FUS(WT) and FUS(R521G) mice.
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Eales KL, Palygin O, O'Loughlin T, Rasooli-Nejad S, Gaestel M, Müller J, Collins DR, Pankratov Y, Corrêa SAL. The MK2/3 cascade regulates AMPAR trafficking and cognitive flexibility. Nat Commun 2014; 5:4701. [PMID: 25134715 PMCID: PMC4143933 DOI: 10.1038/ncomms5701] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 07/16/2014] [Indexed: 12/26/2022] Open
Abstract
The interplay between long-term potentiation and long-term depression (LTD) is thought to be involved in learning and memory formation. One form of LTD expressed in the hippocampus is initiated by the activation of the group 1 metabotropic glutamate receptors (mGluRs). Importantly, mGluRs have been shown to be critical for acquisition of new memories and for reversal learning, processes that are thought to be crucial for cognitive flexibility. Here we provide evidence that MAPK-activated protein kinases 2 and 3 (MK2/3) regulate neuronal spine morphology, synaptic transmission and plasticity. Furthermore, mGluR-LTD is impaired in the hippocampus of MK2/3 double knockout (DKO) mice, an observation that is mirrored by deficits in endocytosis of GluA1 subunits. Consistent with compromised mGluR-LTD, MK2/3 DKO mice have distinctive deficits in hippocampal-dependent spatial reversal learning. These novel findings demonstrate that the MK2/3 cascade plays a strategic role in controlling synaptic plasticity and cognition.
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Affiliation(s)
- Katherine L Eales
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Oleg Palygin
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Thomas O'Loughlin
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | | | - Matthias Gaestel
- Institute of Biochemistry, Hannover Medical University, 30625 Hannover, Germany
| | - Jürgen Müller
- Warwick Medical School, University of Warwick, Coventry CV4 7AL, UK
| | - Dawn R Collins
- Warwick Medical School, University of Warwick, Coventry CV4 7AL, UK
| | - Yuriy Pankratov
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Sonia A L Corrêa
- 1] School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK [2] School of Life Sciences, University of Bradford, Bradford BD7 1DP, UK
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Ribeiro FM, Hamilton A, Doria JG, Guimaraes IM, Cregan SP, Ferguson SS. Metabotropic glutamate receptor 5 as a potential therapeutic target in Huntington's disease. Expert Opin Ther Targets 2014; 18:1293-304. [PMID: 25118797 DOI: 10.1517/14728222.2014.948419] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
INTRODUCTION Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder caused by a polyglutamine expansion in the amino-terminal region of the huntingtin (htt) protein, which underlies the loss of striatal and cortical neurons. Glutamate has been implicated in a number of neurodegenerative diseases, and several studies suggest that the metabotropic glutamate receptor 5 (mGluR5) may represent a target for the treatment of HD. AREAS COVERED The main goal of this review is to discuss the current data in the literature regarding the role of mGluR5 in HD and evaluate the potential of mGluR5 as a therapeutic target for the treatment of HD. mGluR5 is highly expressed in the brain regions affected in HD and is involved in movement control. Moreover, mGluR5 interacts with htt and mutated htt profoundly affects mGluR5 signaling. However, mGluR5 stimulation can activate both neuroprotective and neurotoxic signaling pathways, depending on the context of activation. EXPERT OPINION Although the data published so far strongly indicate that mGluR5 plays a major role in HD-associated neurodegeneration, htt aggregation and motor symptoms, it is not clear whether mGluR5 stimulation can diminish or intensify neuronal cell loss and HD progression. Thus, future experiments will be necessary to further investigate the outcome of drugs acting on mGluR5 for the treatment of neurodegenerative diseases.
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Affiliation(s)
- Fabiola M Ribeiro
- Universidade Federal de Minas Gerais, Departamento de Bioquimica e Imunologia, ICB , Belo Horizonte 31270-901 , Brazil
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45
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Mattison HA, Popovkina D, Kao JPY, Thompson SM. The role of glutamate in the morphological and physiological development of dendritic spines. Eur J Neurosci 2014; 39:1761-70. [PMID: 24661419 PMCID: PMC4043883 DOI: 10.1111/ejn.12536] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 01/31/2014] [Accepted: 02/03/2014] [Indexed: 02/05/2023]
Abstract
Dendritic spines form the postsynaptic half of the synapse but how they form during CNS development remains uncertain, as are the factors that promote their morphological and physiological maturation. One hypothesis posits that filopodia, long motile dendritic processes that are present prior to spine formation, are the precursors to spines. Another hypothesis posits that they form directly from the dendritic shaft. We used microphotolysis of caged glutamate to stimulate individual dendritic processes in young hippocampal slice cultures while recording their morphological and physiological responses. We observed that brief trains of stimuli delivered to immature processes triggered morphological changes within minutes that resulted, in about half of experiments, in a more mature, spine-like appearance such as decreased spine neck length and increased spine head width. We also observed that glutamate-induced inward currents elicited from immature processes were mostly or entirely mediated by NMDARs, whereas responses in those processes with a more mature morphology, regardless of actual developmental age, were mediated by both AMPARs and NMDARs. Consistent with this observation, glutamate-induced morphological changes were largely, but not entirely, prevented by blocking NMDARs. Our observations thus favor a model in which filopodia in the developing nervous system sense and respond to release of glutamate from developing axons, resulting in physiological and morphological maturation.
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Affiliation(s)
- Hayley A. Mattison
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201
- Membrane Biology Training Program, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Dina Popovkina
- Meyerhoff Scholarship Program, University of Maryland, Baltimore County
| | - Joseph P. Y. Kao
- Membrane Biology Training Program, University of Maryland School of Medicine, Baltimore, MD 21201
- Department of Medical Biotechnology, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Scott M. Thompson
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201
- Membrane Biology Training Program, University of Maryland School of Medicine, Baltimore, MD 21201
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46
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Sethna F, Moon C, Wang H. From FMRP function to potential therapies for fragile X syndrome. Neurochem Res 2013; 39:1016-31. [PMID: 24346713 DOI: 10.1007/s11064-013-1229-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Revised: 12/03/2013] [Accepted: 12/12/2013] [Indexed: 12/12/2022]
Abstract
Fragile X syndrome (FXS) is caused by mutations in the fragile X mental retardation 1 (FMR1) gene. Most FXS cases occur due to the expansion of the CGG trinucleotide repeats in the 5' un-translated region of FMR1, which leads to hypermethylation and in turn silences the expression of FMRP (fragile X mental retardation protein). Numerous studies have demonstrated that FMRP interacts with both coding and non-coding RNAs and represses protein synthesis at dendritic and synaptic locations. In the absence of FMRP, the basal protein translation is enhanced and not responsive to neuronal stimulation. The altered protein translation may contribute to functional abnormalities in certain aspects of synaptic plasticity and intracellular signaling triggered by Gq-coupled receptors. This review focuses on the current understanding of FMRP function and potential therapeutic strategies that are mainly based on the manipulation of FMRP targets and knowledge gained from FXS pathophysiology.
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Affiliation(s)
- Ferzin Sethna
- Genetics Program, Michigan State University, East Lansing, MI, 48824, USA
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47
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Ribeiro FM, Devries RA, Hamilton A, Guimaraes IM, Cregan SP, Pires RGW, Ferguson SSG. Metabotropic glutamate receptor 5 knockout promotes motor and biochemical alterations in a mouse model of Huntington's disease. Hum Mol Genet 2013; 23:2030-42. [PMID: 24282028 DOI: 10.1093/hmg/ddt598] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Huntington's disease (HD) is an autosomal-dominant neurodegenerative disorder caused by a polyglutamine expansion in the amino-terminal region of the huntingtin protein, which promotes progressive neuronal cell loss, neurological symptoms and death. In the present study, we show that blockade of mGluR5 with MTEP promotes increased locomotor activity in both control (Hdh(Q20/Q20)) and mutant HD (Hdh(Q111/Q111)) mice. Although acute injection of MTEP increases locomotor activity in both control and mutant HD mice, locomotor activity is increased in only control mice, not mutant HD mice, following the genetic deletion of mGluR5. Interestingly, treatment of mGluR5 knockout mice with either D1 or D2 dopamine antagonists eliminates the increased locomotor activity of mGluR5 knockout mice. Amphetamine treatment increases locomotor activity in control mice, but not mGluR5 null mutant HD mice. However, the loss of mGluR5 expression improves rotarod performance and decreases the number of huntingtin intranuclear inclusions in mutant HD mice. These adaptations may be due to mutant huntingtin-dependent alterations in gene expression, as microarray studies have identified several genes that are altered in mutant, but not wild-type HD mice lacking mGluR5 expression. qPCR experiments confirm that the mRNA transcript levels of dynein heavy chain, dynactin 3 and dynein light chain-6 are altered following the genetic deletion of mGluR5 in mutant HD mice, as compared with wild-type mutant HD mice. Thus, our data suggest that mutant huntingtin protein and mGluR5 exhibit a functional interaction that may be important for HD-mediated alterations in locomotor behavior and the development of intranuclear inclusions.
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Affiliation(s)
- Fabiola M Ribeiro
- Departamento de Bioquimica e Imunologia, ICB, Universidade Federal de Minas Gerais, Belo Horizonte 31270-901, Brazil
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Um JW, Kaufman AC, Kostylev M, Heiss JK, Stagi M, Takahashi H, Kerrisk ME, Vortmeyer A, Wisniewski T, Koleske AJ, Gunther EC, Nygaard HB, Strittmatter SM. Metabotropic glutamate receptor 5 is a coreceptor for Alzheimer aβ oligomer bound to cellular prion protein. Neuron 2013; 79:887-902. [PMID: 24012003 DOI: 10.1016/j.neuron.2013.06.036] [Citation(s) in RCA: 435] [Impact Index Per Article: 39.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/17/2013] [Indexed: 02/07/2023]
Abstract
Soluble amyloid-β oligomers (Aβo) trigger Alzheimer's disease (AD) pathophysiology and bind with high affinity to cellular prion protein (PrP(C)). At the postsynaptic density (PSD), extracellular Aβo bound to lipid-anchored PrP(C) activates intracellular Fyn kinase to disrupt synapses. Here, we screened transmembrane PSD proteins heterologously for the ability to couple Aβo-PrP(C) with Fyn. Only coexpression of the metabotropic glutamate receptor, mGluR5, allowed PrP(C)-bound Aβo to activate Fyn. PrP(C) and mGluR5 interact physically, and cytoplasmic Fyn forms a complex with mGluR5. Aβo-PrP(C) generates mGluR5-mediated increases of intracellular calcium in Xenopus oocytes and in neurons, and the latter is also driven by human AD brain extracts. In addition, signaling by Aβo-PrP(C)-mGluR5 complexes mediates eEF2 phosphorylation and dendritic spine loss. For mice expressing familial AD transgenes, mGluR5 antagonism reverses deficits in learning, memory, and synapse density. Thus, Aβo-PrP(C) complexes at the neuronal surface activate mGluR5 to disrupt neuronal function.
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Affiliation(s)
- Ji Won Um
- Cellular Neuroscience, Neurodegeneration and Repair Program, Departments of Neurology and Neurobiology, Yale University School of Medicine, New Haven, CT 06536, USA
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Micevych P, Sinchak K. Temporal and concentration-dependent effects of oestradiol on neural pathways mediating sexual receptivity. J Neuroendocrinol 2013; 25:1012-23. [PMID: 24028299 PMCID: PMC3943611 DOI: 10.1111/jne.12103] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Revised: 08/13/2013] [Accepted: 09/05/2013] [Indexed: 11/27/2022]
Abstract
The acceptance of oestradiol signalling through receptors found in the cell membrane, as well as, the nucleus, has provided for a re-examination of the timing and location of the actions of oestradiol on neural circuits mediating sexual receptivity (lordosis). Oestradiol membrane signalling involves the transactivation of metabotrophic glutamate receptors (mGluRs) that transduce steroid information through protein kinase C signalling cascades producing rapid activation of lordosis-regulating circuits. It has been known for some time that oestradiol initially produces an inhibition of the medial preoptic nucleus. We have demonstrated that underlying this inhibition is oestradiol acting in the arcuate nucleus to induce β-endorphin release, which inhibits the medial preoptic nucleus through a μ-opioid receptor mechanism. This transient inhibition is relieved by either subsequent progesterone treatment or longer exposure to higher doses of oestradiol to facilitate lordosis behaviour. We review recent findings about oestradiol membrane signalling inducing dendritic spine formation in the arcuate nucleus that is critical for oestradiol induction of sexual receptivity. Moreover, we discuss the evidence that, in addition to oestrogen receptor α, several other putative membrane oestrogen receptors facilitate lordosis behaviour through regulation of the arcuate nucleus. These include the GRP30 and the STX activated Gq-mER. Finally, we report on the importance of GABA acting at GABAB receptors for oestradiol membrane signalling that regulates lordosis circuit activation and sexual receptivity.
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Affiliation(s)
- Paul Micevych
- Department of Neurobiology, David Geffen School of Medicine at UCLA, the Laboratory of Neuroendocrinology, Brain Research Institute, University of California, Los Angeles, CA 90095
| | - Kevin Sinchak
- Department of Biological Sciences, California State University, Long Beach, CA 90840
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50
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Lai KO, Ip NY. Structural plasticity of dendritic spines: the underlying mechanisms and its dysregulation in brain disorders. Biochim Biophys Acta Mol Basis Dis 2013; 1832:2257-63. [PMID: 24012719 DOI: 10.1016/j.bbadis.2013.08.012] [Citation(s) in RCA: 136] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Revised: 08/13/2013] [Accepted: 08/28/2013] [Indexed: 12/17/2022]
Abstract
Dendritic spines are specialized structures on neuronal processes where the majority of excitatory synapses are localized. Spines are highly dynamic, and their stabilization and morphology are influenced by synaptic activity. This extrinsic regulation of spine morphogenesis underlies experience-dependent brain development and information storage within the brain circuitry. In this review, we summarize recent findings that demonstrate the phenomenon of activity-dependent structural plasticity and the molecular mechanisms by which synaptic activity sculpt neuronal connections. Impaired structural plasticity is associated with perturbed brain function in neurodevelopmental disorders such as autism. Information from the mechanistic studies therefore provides important insights into the design of therapeutic strategies for these brain disorders.
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Affiliation(s)
- Kwok-On Lai
- Division of Life Science, Molecular Neuroscience Center and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong
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