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Lenz M, Eichler A, Kruse P, Galanis C, Kleidonas D, Andrieux G, Boerries M, Jedlicka P, Müller U, Deller T, Vlachos A. The Amyloid Precursor Protein Regulates Synaptic Transmission at Medial Perforant Path Synapses. J Neurosci 2023; 43:5290-5304. [PMID: 37369586 PMCID: PMC10359033 DOI: 10.1523/jneurosci.1824-22.2023] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 05/20/2023] [Accepted: 05/24/2023] [Indexed: 06/29/2023] Open
Abstract
The perforant path provides the primary cortical excitatory input to the hippocampus. Because of its important role in information processing and coding, entorhinal projections to the dentate gyrus have been studied in considerable detail. Nevertheless, synaptic transmission between individual connected pairs of entorhinal stellate cells and dentate granule cells remains to be characterized. Here, we have used mouse organotypic entorhino-hippocampal tissue cultures of either sex, in which the entorhinal cortex (EC) to dentate granule cell (GC; EC-GC) projection is present, and EC-GC pairs can be studied using whole-cell patch-clamp recordings. By using cultures of wild-type mice, the properties of EC-GC synapses formed by afferents from the lateral and medial entorhinal cortex were compared, and differences in short-term plasticity were identified. As the perforant path is severely affected in Alzheimer's disease, we used tissue cultures of amyloid precursor protein (APP)-deficient mice to examine the role of APP at this synapse. APP deficiency altered excitatory neurotransmission at medial perforant path synapses, which was accompanied by transcriptomic and ultrastructural changes. Moreover, presynaptic but not postsynaptic APP deletion through the local injection of Cre-expressing adeno-associated viruses in conditional APPflox/flox tissue cultures increased the neurotransmission efficacy at perforant path synapses. In summary, these data suggest a physiological role for presynaptic APP at medial perforant path synapses that may be adversely affected under altered APP processing conditions.SIGNIFICANCE STATEMENT The hippocampus receives input from the entorhinal cortex via the perforant path. These projections to hippocampal dentate granule cells are of utmost importance for learning and memory formation. Although there is detailed knowledge about perforant path projections, the functional synaptic properties at the level of individual connected pairs of neurons are not well understood. In this study, we investigated the role of APP in mediating functional properties and transmission rules in individually connected neurons using paired whole-cell patch-clamp recordings and genetic tools in organotypic tissue cultures. Our results show that presynaptic APP expression limits excitatory neurotransmission via the perforant path, which could be compromised in pathologic conditions such as Alzheimer's disease.
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Affiliation(s)
- Maximilian Lenz
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
- Hannover Medical School, Institute of Neuroanatomy and Cell Biology, 30625 Hannover, Germany
| | - Amelie Eichler
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Pia Kruse
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Christos Galanis
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Dimitrios Kleidonas
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
- Spemann Graduate School of Biology and Medicine, University of Freiburg, 79104 Freiburg, Germany
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Geoffroy Andrieux
- Institute of Medical Bioinformatics and Systems Medicine, Medical Center, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Melanie Boerries
- Institute of Medical Bioinformatics and Systems Medicine, Medical Center, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
- German Cancer Consortium, German Cancer Research Center, 69120 Heidelberg, Germany
| | - Peter Jedlicka
- Interdisciplinary Centre for 3Rs in Animal Research, Faculty of Medicine, Justus-Liebig-University, 35392 Giessen, Germany
- Institute of Clinical Neuroanatomy, Neuroscience Center, Goethe University Frankfurt, 60590 Frankfurt am Main, Germany
- Frankfurt Institute for Advanced Studies, 60438 Frankfurt am Main, Germany
| | - Ulrike Müller
- Institute of Pharmacy and Molecular Biotechnology, Functional Genomics, Ruprecht-Karls University Heidelberg, 69120 Heidelberg, Germany
| | - Thomas Deller
- Institute of Clinical Neuroanatomy, Neuroscience Center, Goethe University Frankfurt, 60590 Frankfurt am Main, Germany
| | - Andreas Vlachos
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
- Center for Basics in Neuromodulation, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
- Center BrainLinks-BrainTools, University of Freiburg, 79104 Freiburg, Germany
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2
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Biasetti L, Rey S, Fowler M, Ratnayaka A, Fennell K, Smith C, Marshall K, Hall C, Vargas-Caballero M, Serpell L, Staras K. Elevated amyloid beta disrupts the nanoscale organization and function of synaptic vesicle pools in hippocampal neurons. Cereb Cortex 2023; 33:1263-1276. [PMID: 35368053 PMCID: PMC9930632 DOI: 10.1093/cercor/bhac134] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 02/02/2022] [Accepted: 03/07/2022] [Indexed: 11/14/2022] Open
Abstract
Alzheimer's disease is linked to increased levels of amyloid beta (Aβ) in the brain, but the mechanisms underlying neuronal dysfunction and neurodegeneration remain enigmatic. Here, we investigate whether organizational characteristics of functional presynaptic vesicle pools, key determinants of information transmission in the central nervous system, are targets for elevated Aβ. Using an optical readout method in cultured hippocampal neurons, we show that acute Aβ42 treatment significantly enlarges the fraction of functional vesicles at individual terminals. We observe the same effect in a chronically elevated Aβ transgenic model (APPSw,Ind) using an ultrastructure-function approach that provides detailed information on nanoscale vesicle pool positioning. Strikingly, elevated Aβ is correlated with excessive accumulation of recycled vesicles near putative endocytic sites, which is consistent with deficits in vesicle retrieval pathways. Using the glutamate reporter, iGluSnFR, we show that there are parallel functional consequences, where ongoing information signaling capacity is constrained. Treatment with levetiracetam, an antiepileptic that dampens synaptic hyperactivity, partially rescues these transmission defects. Our findings implicate organizational and dynamic features of functional vesicle pools as targets in Aβ-driven synaptic impairment, suggesting that interventions to relieve the overloading of vesicle retrieval pathways might have promising therapeutic value.
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Affiliation(s)
- Luca Biasetti
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, BN1 9QG, United Kingdom
| | - Stephanie Rey
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, BN1 9QG, United Kingdom
- National Physical Laboratory, Middlesex, TW11 0LW, United Kingdom
| | - Milena Fowler
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, BN1 9QG, United Kingdom
| | - Arjuna Ratnayaka
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, BN1 9QG, United Kingdom
- Faculty of Medicine, University of Southampton, SO17 1BJ, United Kingdom
| | - Kate Fennell
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, BN1 9QG, United Kingdom
| | - Catherine Smith
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, BN1 9QG, United Kingdom
| | - Karen Marshall
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, BN1 9QG, United Kingdom
| | - Catherine Hall
- Sussex Neuroscience, School of Psychology, University of Sussex, Brighton, BN1 9QH, United Kingdom
| | - Mariana Vargas-Caballero
- School of Biological Sciences, University of Southampton, Highfield Campus, Southampton SO17 1BJ, United Kingdom
| | - Louise Serpell
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, BN1 9QG, United Kingdom
| | - Kevin Staras
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, BN1 9QG, United Kingdom
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3
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Kim J, Wulschner LEG, Oh WC, Ko J. Trans
‐synaptic mechanisms orchestrated by mammalian synaptic cell adhesion molecules. Bioessays 2022; 44:e2200134. [DOI: 10.1002/bies.202200134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 08/18/2022] [Accepted: 08/31/2022] [Indexed: 11/11/2022]
Affiliation(s)
- Jinhu Kim
- Department of Brain Sciences Daegu Gyeongbuk Institute of Science and Technology (DGIST) Daegu Korea
- Center for Synapse Diversity and Specificity DGIST Daegu Korea
| | | | - Won Chan Oh
- Department of Pharmacology University of Colorado School of Medicine Aurora Colorado USA
| | - Jaewon Ko
- Department of Brain Sciences Daegu Gyeongbuk Institute of Science and Technology (DGIST) Daegu Korea
- Center for Synapse Diversity and Specificity DGIST Daegu Korea
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4
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Busquets O, Parcerisas A, Verdaguer E, Ettcheto M, Camins A, Beas-Zarate C, Castro-Torres RD, Auladell C. c-Jun N-Terminal Kinases in Alzheimer's Disease: A Possible Target for the Modulation of the Earliest Alterations. J Alzheimers Dis 2021; 82:S127-S139. [PMID: 33216036 DOI: 10.3233/jad-201053] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Given the highly multifactorial origin of Alzheimer's disease (AD) neuropathology, disentangling and orderly knowing mechanisms involved in sporadic onset are arduous. Nevertheless, when the elements involved are dissected into smaller pieces, the task becomes more accessible. This review aimed to describe the link between c-Jun N-terminal Kinases (JNKs), master regulators of many cellular functions, and the early alterations of AD: synaptic loss and dysregulation of neuronal transport. Both processes have a role in the posterior cognitive decline observed in AD. The manuscript focuses on the molecular mechanisms of glutamatergic, GABA, and cholinergic synapses altered by the presence of amyloid-β aggregates and hyperphosphorylated tau, as well as on several consequences of the disruption of cellular processes linked to neuronal transport that is controlled by the JNK-JIP (c-jun NH2-terminal kinase (JNK)-interacting proteins (JIPs) complex, including the transport of AβPP or autophagosomes.
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Affiliation(s)
- Oriol Busquets
- Department of Pharmacology, Toxicology and Therapeutic Chemistry; Pharmacy and Food Sciences Faculty, Universitat de Barcelona, Barcelona, Spain.,Department of Biochemistry and Biotechnology, Medicine and Health Sciences Faculty, Universitat Rovira i Virgili, Reus, Spain.,Centre for Biomedical Research of Neurodegenerative Diseases (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain.,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain.,Dominick P. Purpura Department of Neurosciences, Albert Einstein College of Medicine, New York City, NY, USA
| | - Antoni Parcerisas
- Centre for Biomedical Research of Neurodegenerative Diseases (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain.,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain.,Department of Cell Biology, Physiology and Immunology, Biology Faculty, Universitat de Barcelona, Barcelona, Spain
| | - Ester Verdaguer
- Centre for Biomedical Research of Neurodegenerative Diseases (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain.,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain.,Department of Cell Biology, Physiology and Immunology, Biology Faculty, Universitat de Barcelona, Barcelona, Spain
| | - Miren Ettcheto
- Department of Pharmacology, Toxicology and Therapeutic Chemistry; Pharmacy and Food Sciences Faculty, Universitat de Barcelona, Barcelona, Spain.,Centre for Biomedical Research of Neurodegenerative Diseases (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain.,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain
| | - Antoni Camins
- Department of Pharmacology, Toxicology and Therapeutic Chemistry; Pharmacy and Food Sciences Faculty, Universitat de Barcelona, Barcelona, Spain.,Centre for Biomedical Research of Neurodegenerative Diseases (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain.,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain
| | - Carlos Beas-Zarate
- Department of Cell and Molecular Biology, Laboratory of Neural Regeneration, C.U.C.B.A., Universidad de Guadalajara, Jalisco, Mexico
| | - Rubén Darío Castro-Torres
- Department of Cell and Molecular Biology, Laboratory of Biology of Neurotransmission, C.U.C.B.A., Universidad de Guadalajara, Jalisco, Mexico
| | - Carme Auladell
- Centre for Biomedical Research of Neurodegenerative Diseases (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain.,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain.,Department of Cell Biology, Physiology and Immunology, Biology Faculty, Universitat de Barcelona, Barcelona, Spain
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5
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Sun X, Wang Q, Blennow K, Zetterberg H, McCarthy M, Loewenstein DA, Vontell R, Yue Z, Zhang B. Association of neurogranin gene expression with Alzheimer's disease pathology in the perirhinal cortex. ALZHEIMER'S & DEMENTIA (NEW YORK, N. Y.) 2021; 7:e12162. [PMID: 33860070 PMCID: PMC8033412 DOI: 10.1002/trc2.12162] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 01/29/2021] [Accepted: 02/10/2021] [Indexed: 12/04/2022]
Abstract
INTRODUCTION Synaptic damage is a key pathology of Alzheimer's disease (AD). The mechanism underlying synaptic vulnerability in AD remains elusive. METHODS Using a large-scale transcriptomic dataset, we analyzed the neurogranin-centered integrative gene network and assessed the correlation of neurogranin (NRGN) gene expression with AD pathology in post mortem brains. We studied the association of NRGN expression with Clinical Dementia Rating (CDR) and neuropathological diagnosis of AD. RESULTS We find that the genes positively correlated with NRGN expression in AD are involved in synaptic transmission and cation channel pathways. NRGN expression is correlated with amyloid and tau pathology in the perirhinal cortex of post mortem brains. NRGN expression is associated with the diagnosis of AD and correlated with CDR. DISCUSSION Transcriptional regulation of the gene encoding for synaptic protein is involved in selective synaptic damage in AD. Identifying the genes associated with synaptic damage pathways in AD may provide targets for intervention.
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Affiliation(s)
- Xiaoyan Sun
- Department of NeurologyUniversity of Miami Miller School of MedicineMiamiFloridaUSA
- Evelyn F. McKnight Brain InstituteBrain Endowment BankUniversity of Miami Miller School of MedicineMiamiFloridaUSA
| | - Qian Wang
- Departments of Neurology and NeuroscienceFriedman Brain Institute, Icahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
- Department of Genetics and Genomic SciencesIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
- Mount Sinai Center for Transformative Disease ModelingIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
- Icahn Institute of Genomics and Multi‐scale BiologyIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
| | - Kaj Blennow
- Department of Psychiatry and NeurochemistryInstitute of Neuroscience and PhysiologySahlgrenska Academy at the University GothenburgMölndalSweden
- Clinical Neurochemistry LaboratorySahlgrenska University HospitalMölndalSweden
| | - Henrik Zetterberg
- Department of Psychiatry and NeurochemistryInstitute of Neuroscience and PhysiologySahlgrenska Academy at the University GothenburgMölndalSweden
- Clinical Neurochemistry LaboratorySahlgrenska University HospitalMölndalSweden
- Department of Neurodegenerative DiseaseUCL Institute of NeurologyLondonUK
- UK Dementia Research Institute at UCLLondonUK
| | - Micheline McCarthy
- Department of NeurologyUniversity of Miami Miller School of MedicineMiamiFloridaUSA
| | - David A. Loewenstein
- Department of Psychiatry and Behavioral SciencesCenter for Cognitive Neuroscience and AgingUniversity of Miami Miller School of MedicineMiamiFloridaUSA
| | - Regina Vontell
- Department of NeurologyUniversity of Miami Miller School of MedicineMiamiFloridaUSA
- Evelyn F. McKnight Brain InstituteBrain Endowment BankUniversity of Miami Miller School of MedicineMiamiFloridaUSA
| | - Zhenyu Yue
- Departments of Neurology and NeuroscienceFriedman Brain Institute, Icahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
| | - Bin Zhang
- Department of Genetics and Genomic SciencesIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
- Mount Sinai Center for Transformative Disease ModelingIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
- Icahn Institute of Genomics and Multi‐scale BiologyIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
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6
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Abstract
The Amyloid Precursor Protein (APP) is infamous for its proposed pivotal role in the pathogenesis of Alzheimer’s disease (AD). Much research on APP focusses on potential contributions to neurodegeneration, mostly based on mouse models with altered expression or mutated forms of APP. However, cumulative evidence from recent years indicates the indispensability of APP and its metabolites for normal brain physiology. APP contributes to the regulation of synaptic transmission, plasticity, and calcium homeostasis. It plays an important role during development and it exerts neuroprotective effects. Of particular importance is the soluble secreted fragment APPsα which mediates many of its physiological actions, often counteracting the effects of the small APP-derived peptide Aβ. Understanding the contribution of APP for normal functions of the nervous system is of high importance, both from a basic science perspective and also as a basis for generating new pathophysiological concepts and therapeutic approaches in AD. In this article, we review the physiological functions of APP and its metabolites, focusing on synaptic transmission, plasticity, calcium signaling, and neuronal network activity.
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Affiliation(s)
- Dimitri Hefter
- Institute of Physiology and Pathophysiology, Heidelberg University, Heidelberg, Germany.,RG Animal Models in Psychiatry, Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Heidelberg, Germany
| | - Susann Ludewig
- Helmholtz Centre for Infection Research, Neuroinflammation and Neurodegeneration Group, Braunschweig, Germany.,Cellular Neurobiology, Zoological Institute, Technical University Braunschweig, Braunschweig, Germany
| | - Andreas Draguhn
- Institute of Physiology and Pathophysiology, Heidelberg University, Heidelberg, Germany
| | - Martin Korte
- Helmholtz Centre for Infection Research, Neuroinflammation and Neurodegeneration Group, Braunschweig, Germany.,Cellular Neurobiology, Zoological Institute, Technical University Braunschweig, Braunschweig, Germany
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7
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Delfino D, Rossetti DV, Martelli C, Inserra I, Vincenzoni F, Castagnola M, Urbani A, Scarpa S, Fuso A, Cavallaro RA, Desiderio C. Exploring the brain tissue proteome of TgCRND8 Alzheimer's Disease model mice under B vitamin deficient diet induced hyperhomocysteinemia by LC-MS top-down platform. J Chromatogr B Analyt Technol Biomed Life Sci 2019; 1124:165-172. [PMID: 31202182 DOI: 10.1016/j.jchromb.2019.06.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 05/28/2019] [Accepted: 06/04/2019] [Indexed: 01/23/2023]
Abstract
The multifactorial nature of Late Onset Alzheimer's Disease (LOAD), the AD form of major relevance on epidemiological and social aspects, has driven the original investigation by LC-MS and top-down proteomics approach of the protein repertoire of the brain tissue of TgCRND8 model mice fed with a diet deficient in B vitamins. The analysis of the acid-soluble fraction of brain tissue homogenates identified a list of proteins and peptides, proteoforms and PTMs. In order to disclose possible modulations, their relative quantification in wild type and AD model mice under both B vitamin deficient and control diets was performed. The levels of metallothionein III, guanine nucleotide-binding protein G(I)/G(S)/G(O) subunit gamma-2 and brain acid soluble protein 1 showed statistically significant alterations depending on genotype, diet or both effects, respectively. Particularly, metallothionein III exhibited increased levels in TgCRND8 mice under B vitamin deficient diet with respect to wild type mice under both diets. Brain acid soluble protein 1 showed the opposite, revealing decreased levels in all diet groups of AD model mice with respect to wild type mice in control diet. Lower levels of brain acid soluble protein 1 were also observed in wild type mice under deficiency of B vitamins. These results, besides contributing to increase the knowledge of AD at molecular level, give new suggestions for deeply investigating metallothionein III and brain acid soluble protein 1 in AD.
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Affiliation(s)
- Daniela Delfino
- Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Roma, Italia
| | - Diana Valeria Rossetti
- Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Roma, Italia; Fondazione Policlinico Universitario A. Gemelli IRCCS, Roma, Italia
| | - Claudia Martelli
- Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Roma, Italia
| | - Ilaria Inserra
- Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Roma, Italia
| | - Federica Vincenzoni
- Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Roma, Italia; Fondazione Policlinico Universitario A. Gemelli IRCCS, Roma, Italia
| | - Massimo Castagnola
- Istituto di Chimica del Riconoscimento Molecolare, Consiglio Nazionale delle Ricerche, Rome, Italy; Laboratorio di Proteomica e Metabonomica, IRCCS, Fondazione Santa Lucia, Roma, Italia
| | - Andrea Urbani
- Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Roma, Italia; Area Diagnostica di Laboratorio, Fondazione Policlinico Universitario Agostino Gemelli - IRCCS, Roma, Italy
| | - Sigfrido Scarpa
- Dipartimento di Chirurgia "P. Valdoni", Sapienza Università di Roma, Rome, Italy
| | - Andrea Fuso
- Dipartimento di Medicina Sperimentale, Sapienza Università di Roma, Rome, Italy
| | - Rosaria A Cavallaro
- Dipartimento di Chirurgia "P. Valdoni", Sapienza Università di Roma, Rome, Italy
| | - Claudia Desiderio
- Istituto di Chimica del Riconoscimento Molecolare, Consiglio Nazionale delle Ricerche, Rome, Italy.
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8
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Kilinc D. The Emerging Role of Mechanics in Synapse Formation and Plasticity. Front Cell Neurosci 2018; 12:483. [PMID: 30574071 PMCID: PMC6291423 DOI: 10.3389/fncel.2018.00483] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Accepted: 11/27/2018] [Indexed: 12/26/2022] Open
Abstract
The regulation of synaptic strength forms the basis of learning and memory, and is a key factor in understanding neuropathological processes that lead to cognitive decline and dementia. While the mechanical aspects of neuronal development, particularly during axon growth and guidance, have been extensively studied, relatively little is known about the mechanical aspects of synapse formation and plasticity. It is established that a filamentous actin network with complex spatiotemporal behavior controls the dendritic spine shape and size, which is thought to be crucial for activity-dependent synapse plasticity. Accordingly, a number of actin binding proteins have been identified as regulators of synapse plasticity. On the other hand, a number of cell adhesion molecules (CAMs) are found in synapses, some of which form transsynaptic bonds to align the presynaptic active zone (PAZ) with the postsynaptic density (PSD). Considering that these CAMs are key components of cellular mechanotransduction, two critical questions emerge: (i) are synapses mechanically regulated? and (ii) does disrupting the transsynaptic force balance lead to (or exacerbate) synaptic failure? In this mini review article, I will highlight the mechanical aspects of synaptic structures-focusing mainly on cytoskeletal dynamics and CAMs-and discuss potential mechanoregulation of synapses and its relevance to neurodegenerative diseases.
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Affiliation(s)
- Devrim Kilinc
- INSERM U1167, Institut Pasteur de Lille, Lille, France
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9
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Beckert B, Acker-Palmer A, Volknandt W. Aβ42 oligomers impair the bioenergetic activity in hippocampal synaptosomes derived from APP-KO mice. Biol Chem 2018; 399:453-465. [PMID: 29337689 DOI: 10.1515/hsz-2017-0238] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 12/20/2017] [Indexed: 11/15/2022]
Abstract
Employing hippocampal synaptosomes from amyloid precursor protein (APP)-deleted mice we analyzed the immediate effects of amyloid beta peptide 42 (Aβ42) peptide in its oligomeric or fibrillar assembly or of soluble amyloid precursor protein alpha (sAPPα) protein on their bioenergetic activity. Upon administration of oligomeric Aβ42 peptide for 30 min we observed a robust decrease both in mitochondrial activity and in mitochondrial membrane potential (MMP). In contrast the respective fibrillary or scrambled peptides showed no effect, indicating that inhibition strictly depends on the oligomerization status of the peptide. Hippocampal synaptosomes from old APP-KO mice revealed a further reduction of their already impaired bioenergetic activity upon incubation with 10 μm Aβ42 peptide. In addition we evaluated the influence of the sAPPα protein on mitochondrial activity of hippocampal synaptosomes derived from young or old APP-KO animals. In neither case 20 nm nor 200 nm sAPPα protein had an effect on mitochondrial metabolic activity. Our findings demonstrate that hippocampal synaptosomes derived from APP-KO mice are a most suitable model system to evaluate the impact of Aβ42 peptide on its bioenergetic activity and to further elucidate the molecular mechanisms underlying the impairments by oligomeric Aβ42 on mitochondrial function. Our data demonstrate that extracellular Aβ42 peptide is taken up into synaptosomes where it immediately attenuates mitochondrial activity.
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Affiliation(s)
- Benedikt Beckert
- Institute of Cell Biology and Neuroscience and Buchmann Institute for Molecular Life Sciences (BMLS), University of Frankfurt, Max-von-Laue-Str. 15, D-60438, Frankfurt/Main, Germany
| | - Amparo Acker-Palmer
- Institute of Cell Biology and Neuroscience and Buchmann Institute for Molecular Life Sciences (BMLS), University of Frankfurt, Max-von-Laue-Str. 15, D-60438, Frankfurt/Main, Germany
- Max Planck Institute for Brain Research, Max-von-Laue-Str. 4, D-60438 Frankfurt/Main, Germany
| | - Walter Volknandt
- Institute of Cell Biology and Neuroscience and Buchmann Institute for Molecular Life Sciences (BMLS), University of Frankfurt, Max-von-Laue-Str. 15, D-60438, Frankfurt/Main, Germany
- Department for Molecular and Cellular Neurobiology, Goethe University Frankfurt, Max-von-Laue-Str. 13, D-60438 Frankfurt, Germany
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10
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Abstract
Synapse is the basic structural and functional component for neural communication in the brain. The presynaptic terminal is the structural and functionally essential area that initiates communication and maintains the continuous functional neural information flow. It contains synaptic vesicles (SV) filled with neurotransmitters, an active zone for release, and numerous proteins for SV fusion and retrieval. The structural and functional synaptic plasticity is a representative characteristic; however, it is highly vulnerable to various pathological conditions. In fact, synaptic alteration is thought to be central to neural disease processes. In particular, the alteration of the structural and functional phenotype of the presynaptic terminal is a highly significant evidence for neural diseases. In this review, we specifically describe structural and functional alteration of nerve terminals in several neurodegenerative diseases, including Alzheimer’s disease (AD), Parkinson’s disease (PD), Amyotrophic lateral sclerosis (ALS), and Huntington’s disease (HD).
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Affiliation(s)
- Jae Ryul Bae
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Korea
| | - Sung Hyun Kim
- Department of Physiology, School of Medicine, Kyung Hee University, Seoul 02447, Korea
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11
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Dai MH, Zheng H, Zeng LD, Zhang Y. The genes associated with early-onset Alzheimer's disease. Oncotarget 2018; 9:15132-15143. [PMID: 29599933 PMCID: PMC5871104 DOI: 10.18632/oncotarget.23738] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 10/14/2017] [Indexed: 01/31/2023] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder that accounts for the most cases of dementia, which is characterized by the deposition of dense plaques of amyloid beta (Aβ) plaques and neurofibrillary tangles consisting of hyperphosphorylated tau. The two main types of AD can be classified as early-onset AD (EOAD, onset < 65 years) and late-onset AD (LOAD, onset ≥ 65 years). Evidence from family and twin studies indicate that genetic factors are estimated to play a role in at least 80% of AD cases. The first milestone with linkage analysis revealed the mutations in APP, PSEN1, and PSEN2 genes that cause EOAD. But pathogenic mutations in these three genes can only explain a small fraction of EOAD families. The additional disease-causing genes have not yet been identified. This review provides an overview of the genetic basis of EOAD and the relationship between the functions of these risk genes and the neuropathologic features of AD. A better understanding of genetic mechanisms underlying EOAD pathogenesis and the potentially molecular mechanisms of neurodegeneration will lead to the development of effective diagnosis and treatment strategies for this devastating disease.
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Affiliation(s)
- Meng-Hui Dai
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Hui Zheng
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Ling-Dan Zeng
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Yan Zhang
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
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12
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Human Brain-Derived Aβ Oligomers Bind to Synapses and Disrupt Synaptic Activity in a Manner That Requires APP. J Neurosci 2017; 37:11947-11966. [PMID: 29101243 DOI: 10.1523/jneurosci.2009-17.2017] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Revised: 09/19/2017] [Accepted: 09/29/2017] [Indexed: 12/20/2022] Open
Abstract
Compelling genetic evidence links the amyloid precursor protein (APP) to Alzheimer's disease (AD) and several theories have been advanced to explain the relationship. A leading hypothesis proposes that a small amphipathic fragment of APP, the amyloid β-protein (Aβ), self-associates to form soluble aggregates that impair synaptic and network activity. Here, we used the most disease-relevant form of Aβ, protein isolated from AD brain. Using this material, we show that the synaptotoxic effects of Aβ depend on expression of APP and that the Aβ-mediated impairment of synaptic plasticity is accompanied by presynaptic effects that disrupt the excitatory/inhibitory (E/I) balance. The net increase in the E/I ratio and inhibition of plasticity are associated with Aβ localizing to synapses and binding of soluble Aβ aggregates to synapses requires the expression of APP. Our findings indicate a role for APP in AD pathogenesis beyond the generation of Aβ and suggest modulation of APP expression as a therapy for AD.SIGNIFICANCE STATEMENT Here, we report on the plasticity-disrupting effects of amyloid β-protein (Aβ) isolated from Alzheimer's disease (AD) brain and the requirement of amyloid precursor protein (APP) for these effects. We show that Aβ-containing AD brain extracts block hippocampal LTP, augment glutamate release probability, and disrupt the excitatory/inhibitory balance. These effects are associated with Aβ localizing to synapses and genetic ablation of APP prevents both Aβ binding and Aβ-mediated synaptic dysfunctions. Our results emphasize the importance of APP in AD and should stimulate new studies to elucidate APP-related targets suitable for pharmacological manipulation.
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13
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Liu A, Zhang Y, Han L, He G, Xie W, Zhou Z, Jia Z. Regulation of Neurotransmitter Release by Amyloid Precursor Protein Through Synapsin Phosphorylation. Neurochem Res 2017; 44:683-691. [PMID: 29052089 DOI: 10.1007/s11064-017-2418-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 10/01/2017] [Accepted: 10/09/2017] [Indexed: 12/19/2022]
Abstract
Abnormal processing of amyloid precursor protein (APP) and aggregation of the Aβ peptide are known to play a key role in the pathogenesis of Alzheimer disease, but the function of endogenous APP under normal physiological conditions remains poorly understood. In this study, we investigated presynaptic changes in APP knockout (KO) mice. We demonstrate that both sucrose-induced neurotransmission and synaptic depletion in response to high frequency stimulation are significantly enhanced in APP KO compared to wild type littermates. In addition, the level of phosphorylated forms of synapsins, but not total synapsins, is elevated in the KO mice. Furthermore, we show that the inhibition of L-type calcium channels normalizes phosphorylated synapsins and slows down the high frequency induced synaptic depletion in APP KO mice. These results suggest a new mechanism by which APP regulates synaptic vesicle dynamics through synapsin-dependent phosphorylation.
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Affiliation(s)
- An Liu
- Institute of Life Sciences, The Key Laboratory of Developmental Genes and Human Disease, Jiangsu Co-innovation Center of Neuroregeneration, Southeast University, Nanjing, 210096, China
| | - Ying Zhang
- Institute of Life Sciences, The Key Laboratory of Developmental Genes and Human Disease, Jiangsu Co-innovation Center of Neuroregeneration, Southeast University, Nanjing, 210096, China
| | - Lifang Han
- Institute of Life Sciences, The Key Laboratory of Developmental Genes and Human Disease, Jiangsu Co-innovation Center of Neuroregeneration, Southeast University, Nanjing, 210096, China
| | - Guiqin He
- Institute of Life Sciences, The Key Laboratory of Developmental Genes and Human Disease, Jiangsu Co-innovation Center of Neuroregeneration, Southeast University, Nanjing, 210096, China
| | - Wei Xie
- Institute of Life Sciences, The Key Laboratory of Developmental Genes and Human Disease, Jiangsu Co-innovation Center of Neuroregeneration, Southeast University, Nanjing, 210096, China
| | - Zikai Zhou
- Institute of Life Sciences, The Key Laboratory of Developmental Genes and Human Disease, Jiangsu Co-innovation Center of Neuroregeneration, Southeast University, Nanjing, 210096, China
| | - Zhengping Jia
- Neurosciences & Mental Health, the Hospital for Sick Children, 555 University Ave., Toronto, ON, M5G 1X8, Canada. .,Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada.
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14
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Saburova EA, Vasiliev AN, Kravtsova VV, Ryabova EV, Zefirov AL, Bolshakova OI, Sarantseva SV, Krivoi II. Human APP Gene Expression Alters Active Zone Distribution and Spontaneous Neurotransmitter Release at the Drosophila Larval Neuromuscular Junction. Neural Plast 2017; 2017:9202584. [PMID: 28770114 PMCID: PMC5523229 DOI: 10.1155/2017/9202584] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 06/07/2017] [Indexed: 12/11/2022] Open
Abstract
This study provides further insight into the molecular mechanisms that control neurotransmitter release. Experiments were performed on larval neuromuscular junctions of transgenic Drosophila melanogaster lines with different levels of human amyloid precursor protein (APP) production. To express human genes in motor neurons of Drosophila, the UAS-GAL4 system was used. Human APP gene expression increased the number of synaptic boutons per neuromuscular junction. The total number of active zones, detected by Bruchpilot protein puncta distribution, remained unchanged; however, the average number of active zones per bouton decreased. These disturbances were accompanied by a decrease in frequency of miniature excitatory junction potentials without alteration in random nature of spontaneous quantal release. Similar structural and functional changes were observed with co-overexpression of human APP and β-secretase genes. In Drosophila line with expression of human amyloid-β42 peptide itself, parameters analyzed did not differ from controls, suggesting the specificity of APP effects. These results confirm the involvement of APP in synaptogenesis and provide evidence to suggest that human APP overexpression specifically disturbs the structural and functional organization of active zone and results in altered Bruchpilot distribution and lowered probability of spontaneous neurotransmitter release.
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Affiliation(s)
- Ekaterina A. Saburova
- Department of General Physiology, St. Petersburg State University, St. Petersburg 199034, Russia
| | - Alexander N. Vasiliev
- Department of General Physiology, St. Petersburg State University, St. Petersburg 199034, Russia
| | - Violetta V. Kravtsova
- Department of General Physiology, St. Petersburg State University, St. Petersburg 199034, Russia
| | - Elena V. Ryabova
- B.P. Konstantinov Petersburg Nuclear Physics Institute, National Research Centre “Kurchatov Institute”, Gatchina 188300, Russia
| | - Andrey L. Zefirov
- Department of Normal Physiology, Kazan State Medical University, Kazan 420012, Russia
| | - Olga I. Bolshakova
- B.P. Konstantinov Petersburg Nuclear Physics Institute, National Research Centre “Kurchatov Institute”, Gatchina 188300, Russia
| | - Svetlana V. Sarantseva
- B.P. Konstantinov Petersburg Nuclear Physics Institute, National Research Centre “Kurchatov Institute”, Gatchina 188300, Russia
| | - Igor I. Krivoi
- Department of General Physiology, St. Petersburg State University, St. Petersburg 199034, Russia
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15
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Yan L, Deng Y, Gao J, Liu Y, Li F, Shi J, Gong Q. Icariside II Effectively Reduces Spatial Learning and Memory Impairments in Alzheimer's Disease Model Mice Targeting Beta-Amyloid Production. Front Pharmacol 2017; 8:106. [PMID: 28337142 PMCID: PMC5340752 DOI: 10.3389/fphar.2017.00106] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 02/21/2017] [Indexed: 01/13/2023] Open
Abstract
Icariside II (ICS II) is a broad-spectrum anti-cancer natural compound extracted from Herba Epimedii Maxim. Recently, the role of ICS II has been investigated in central nervous system, especially have a neuroprotective effect in Alzheimer’s disease (AD). In this study, we attempted to investigate the effects of ICS II, on cognitive deficits and beta-amyloid (Aβ) production in APPswe/PS1dE9 (APP/PS1) double transgenic mice. It was found that chronic ICS II administrated not only effectively ameliorated cognitive function deficits, but also inhibited neuronal degeneration and reduced the formation of plaque burden. ICS II significantly suppressed Aβ production via promoting non-amyloidogenic APP cleavage process by up-regulating a disintegrin and metalloproteinase domain 10 (ADAM10) expression, inhibited amyloidogenic APP processing pathway by down-regulating amyloid precursor protein (APP) and β-site amyloid precursor protein cleavage enzyme 1 (BACE1) expression in APP/PS1 transgenic mice. Meanwhile, ICS II attenuated peroxisome proliferator-activated receptor-γ (PPARγ) degradation as well as inhibition of eukaryotic initiation factor α phosphorylation (p-eIF2α) and PKR endoplasmic reticulum regulating kinase phosphorylation (p-PERK). Moreover, phosphodiesterase type 5 inhibitors (PDE5-Is) have recently emerged as a possible therapeutic target for cognitive enhancement via inhibiting Aβ levels, and we also found that ICS II markedly decreased phosphodiesterase-5A (PDE5A) expression. In conclusion, the present study demonstrates that ICS II could attenuate spatial learning and memory impairments in APP/PS1 transgenic mice. This protection appears to be due to the increased ADAM10 expression and decreased expression of both APP and BACE1, resulting in inhibition of Aβ production in the hippocampus and cortex. Inhibition of PPARγ degradation and PERK/eIF2α phosphorylation are involved in the course, therefore suggesting that ICS II might be a promising potential compound for the treatment of AD.
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Affiliation(s)
- Lingli Yan
- Department of Pharmacology and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University Zunyi, China
| | - Yuanyuan Deng
- Department of Pharmacology and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University Zunyi, China
| | - Jianmei Gao
- Department of Pharmacy, Zunyi Medical University Zunyi, China
| | - Yuangui Liu
- Department of Pharmacology and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University Zunyi, China
| | - Fei Li
- Department of Pharmacology and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University Zunyi, China
| | - Jingshan Shi
- Department of Pharmacology and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University Zunyi, China
| | - Qihai Gong
- Department of Pharmacology and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University Zunyi, China
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16
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Weingarten J, Weingarten M, Wegner M, Volknandt W. APP-A Novel Player within the Presynaptic Active Zone Proteome. Front Mol Neurosci 2017; 10:43. [PMID: 28265241 PMCID: PMC5316543 DOI: 10.3389/fnmol.2017.00043] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Accepted: 02/07/2017] [Indexed: 11/13/2022] Open
Abstract
The amyloid precursor protein (APP) was discovered in the 1980s as the precursor protein of the amyloid A4 peptide. The amyloid A4 peptide, also known as A-beta (Aβ), is the main constituent of senile plaques implicated in Alzheimer's disease (AD). In association with the amyloid deposits, increasing impairments in learning and memory as well as the degeneration of neurons especially in the hippocampus formation are hallmarks of the pathogenesis of AD. Within the last decades much effort has been expended into understanding the pathogenesis of AD. However, little is known about the physiological role of APP within the central nervous system (CNS). Allocating APP to the proteome of the highly dynamic presynaptic active zone (PAZ) identified APP as a novel player within this neuronal communication and signaling network. The analysis of the hippocampal PAZ proteome derived from APP-mutant mice demonstrates that APP is tightly embedded in the underlying protein network. Strikingly, APP deletion accounts for major dysregulation within the PAZ proteome network. Ca2+-homeostasis, neurotransmitter release and mitochondrial function are affected and resemble the outcome during the pathogenesis of AD. The observed changes in protein abundance that occur in the absence of APP as well as in AD suggest that APP is a structural and functional regulator within the hippocampal PAZ proteome. Within this review article, we intend to introduce APP as an important player within the hippocampal PAZ proteome and to outline the impact of APP deletion on individual PAZ proteome subcommunities.
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Affiliation(s)
- Jens Weingarten
- Institute for Cell Biology and Neuroscience, Biologicum and BMLS, Goethe University Frankfurt am Main, Germany
| | - Melanie Weingarten
- Institute for Cell Biology and Neuroscience, Biologicum and BMLS, Goethe University Frankfurt am Main, Germany
| | - Martin Wegner
- Department of Molecular Bioinformatics, Goethe University Frankfurt am Main, Germany
| | - Walter Volknandt
- Institute for Cell Biology and Neuroscience, Biologicum and BMLS, Goethe University Frankfurt am Main, Germany
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17
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Ludewig S, Korte M. Novel Insights into the Physiological Function of the APP (Gene) Family and Its Proteolytic Fragments in Synaptic Plasticity. Front Mol Neurosci 2017; 9:161. [PMID: 28163673 PMCID: PMC5247455 DOI: 10.3389/fnmol.2016.00161] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 12/14/2016] [Indexed: 12/31/2022] Open
Abstract
The amyloid precursor protein (APP) is well known to be involved in the pathophysiology of Alzheimer's disease (AD) via its cleavage product amyloid ß (Aß). However, the physiological role of APP, its various proteolytic products and the amyloid precursor-like proteins 1 and 2 (APLP1/2) are still not fully clarified. Interestingly, it has been shown that learning and memory processes represented by functional and structural changes at synapses are altered in different APP and APLP1/2 mouse mutants. In addition, APP and its fragments are implicated in regulating synaptic strength further reinforcing their modulatory role at the synapse. While APLP2 and APP are functionally redundant, the exclusively CNS expressed APLP1, might have individual roles within the synaptic network. The proteolytic product of non-amyloidogenic APP processing, APPsα, emerged as a neurotrophic peptide that facilitates long-term potentiation (LTP) and restores impairments occurring with age. Interestingly, the newly discovered η-secretase cleavage product, An-α acts in the opposite direction, namely decreasing LTP. In this review we summarize recent findings with emphasis on the physiological role of the APP gene family and its proteolytic products on synaptic function and plasticity, especially during processes of hippocampal LTP. Therefore, we focus on literature that provide electrophysiological data by using different mutant mouse strains either lacking full-length or parts of the APP proteins or that utilized secretase inhibitors as well as secreted APP fragments.
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Affiliation(s)
- Susann Ludewig
- Division of Cellular Neurobiology, Zoological Institute, TU Braunschweig Braunschweig, Germany
| | - Martin Korte
- Division of Cellular Neurobiology, Zoological Institute, TU BraunschweigBraunschweig, Germany; Helmholtz Centre for Infection Research, AG NINDBraunschweig, Germany
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18
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Laßek M, Weingarten J, Wegner M, Neupärtl M, Array TN, Harde E, Beckert B, Golghalyani V, Ackermann J, Koch I, Müller UC, Karas M, Acker-Palmer A, Volknandt W. APP Deletion Accounts for Age-Dependent Changes in the Bioenergetic Metabolism and in Hyperphosphorylated CaMKII at Stimulated Hippocampal Presynaptic Active Zones. Front Synaptic Neurosci 2017; 9:1. [PMID: 28163681 PMCID: PMC5247443 DOI: 10.3389/fnsyn.2017.00001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Accepted: 01/05/2017] [Indexed: 11/13/2022] Open
Abstract
Synaptic release sites are characterized by exocytosis-competent synaptic vesicles tightly anchored to the presynaptic active zone (PAZ) whose proteome orchestrates the fast signaling events involved in synaptic vesicle cycle and plasticity. Allocation of the amyloid precursor protein (APP) to the PAZ proteome implicated a functional impact of APP in neuronal communication. In this study, we combined state-of-the-art proteomics, electrophysiology and bioinformatics to address protein abundance and functional changes at the native hippocampal PAZ in young and old APP-KO mice. We evaluated if APP deletion has an impact on the metabolic activity of presynaptic mitochondria. Furthermore, we quantified differences in the phosphorylation status after long-term-potentiation (LTP) induction at the purified native PAZ. We observed an increase in the phosphorylation of the signaling enzyme calmodulin-dependent kinase II (CaMKII) only in old APP-KO mice. During aging APP deletion is accompanied by a severe decrease in metabolic activity and hyperphosphorylation of CaMKII. This attributes an essential functional role to APP at hippocampal PAZ and putative molecular mechanisms underlying the age-dependent impairments in learning and memory in APP-KO mice.
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Affiliation(s)
- Melanie Laßek
- Institute for Cell Biology and Neuroscience, Biologicum and BMLS, Johann Wolfgang Goethe-Universität Frankfurt, Germany
| | - Jens Weingarten
- Institute for Cell Biology and Neuroscience, Biologicum and BMLS, Johann Wolfgang Goethe-Universität Frankfurt, Germany
| | - Martin Wegner
- Molecular Bioinformatics, Johann Wolfgang Goethe-Universität Frankfurt, Germany
| | - Moritz Neupärtl
- Institute of Pharmaceutical Chemistry, Johann Wolfgang Goethe-Universität Frankfurt, Germany
| | | | - Eva Harde
- Institute for Cell Biology and Neuroscience, Biologicum and BMLS, Johann Wolfgang Goethe-UniversitätFrankfurt, Germany; Max Planck Institute for Brain ResearchFrankfurt, Germany
| | - Benedikt Beckert
- Institute for Cell Biology and Neuroscience, Biologicum and BMLS, Johann Wolfgang Goethe-Universität Frankfurt, Germany
| | - Vahid Golghalyani
- Institute of Pharmaceutical Chemistry, Johann Wolfgang Goethe-Universität Frankfurt, Germany
| | - Jörg Ackermann
- Molecular Bioinformatics, Johann Wolfgang Goethe-Universität Frankfurt, Germany
| | - Ina Koch
- Molecular Bioinformatics, Johann Wolfgang Goethe-Universität Frankfurt, Germany
| | - Ulrike C Müller
- Department of Pharmacy and Molecular Biotechnology, University Heidelberg Heidelberg, Germany
| | - Michael Karas
- Institute of Pharmaceutical Chemistry, Johann Wolfgang Goethe-Universität Frankfurt, Germany
| | - Amparo Acker-Palmer
- Institute for Cell Biology and Neuroscience, Biologicum and BMLS, Johann Wolfgang Goethe-UniversitätFrankfurt, Germany; Max Planck Institute for Brain ResearchFrankfurt, Germany
| | - Walter Volknandt
- Institute for Cell Biology and Neuroscience, Biologicum and BMLS, Johann Wolfgang Goethe-Universität Frankfurt, Germany
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19
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Del Turco D, Paul MH, Schlaudraff J, Hick M, Endres K, Müller UC, Deller T. Region-Specific Differences in Amyloid Precursor Protein Expression in the Mouse Hippocampus. Front Mol Neurosci 2016; 9:134. [PMID: 27965537 PMCID: PMC5126089 DOI: 10.3389/fnmol.2016.00134] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 11/15/2016] [Indexed: 12/20/2022] Open
Abstract
The physiological role of amyloid precursor protein (APP) has been extensively investigated in the rodent hippocampus. Evidence suggests that APP plays a role in synaptic plasticity, dendritic and spine morphogenesis, neuroprotection and—at the behavioral level—hippocampus-dependent forms of learning and memory. Intriguingly, however, studies focusing on the role of APP in synaptic plasticity have reported diverging results and considerable differences in effect size between the dentate gyrus (DG) and area CA1 of the mouse hippocampus. We speculated that regional differences in APP expression could underlie these discrepancies and studied the expression of APP in both regions using immunostaining, in situ hybridization (ISH), and laser microdissection (LMD) in combination with quantitative reverse transcription polymerase chain reaction (RT-qPCR) and western blotting. In sum, our results show that APP is approximately 1.7-fold higher expressed in pyramidal cells of Ammon’s horn than in granule cells of the DG. This regional difference in APP expression may explain why loss-of-function approaches using APP-deficient mice revealed a role for APP in Hebbian plasticity in area CA1, whereas this could not be shown in the DG of the same APP mutants.
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Affiliation(s)
- Domenico Del Turco
- Institute of Clinical Neuroanatomy, Neuroscience Center, Goethe-University Frankfurt, Germany
| | - Mandy H Paul
- Institute of Clinical Neuroanatomy, Neuroscience Center, Goethe-University Frankfurt, Germany
| | - Jessica Schlaudraff
- Institute of Clinical Neuroanatomy, Neuroscience Center, Goethe-University Frankfurt, Germany
| | - Meike Hick
- Institute of Clinical Neuroanatomy, Neuroscience Center, Goethe-UniversityFrankfurt, Germany; Institute of Pharmacy and Molecular Biotechnology (IPMB), Heidelberg UniversityHeidelberg, Germany
| | - Kristina Endres
- Clinic for Psychiatry and Psychotherapy, University Medical Center Mainz Mainz, Germany
| | - Ulrike C Müller
- Institute of Pharmacy and Molecular Biotechnology (IPMB), Heidelberg University Heidelberg, Germany
| | - Thomas Deller
- Institute of Clinical Neuroanatomy, Neuroscience Center, Goethe-University Frankfurt, Germany
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