1
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Chrobak AA, Pańczyszyn-Trzewik P, Król P, Pawelec-Bąk M, Dudek D, Siwek M. New Light on Prions: Putative Role of PrP c in Pathophysiology of Mood Disorders. Int J Mol Sci 2024; 25:2967. [PMID: 38474214 PMCID: PMC10932175 DOI: 10.3390/ijms25052967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 02/28/2024] [Accepted: 03/03/2024] [Indexed: 03/14/2024] Open
Abstract
Mood disorders are highly prevalent and heterogenous mental illnesses with devastating rates of mortality and treatment resistance. The molecular basis of those conditions involves complex interplay between genetic and environmental factors. Currently, there are no objective procedures for diagnosis, prognosis and personalization of patients' treatment. There is an urgent need to search for novel molecular targets for biomarkers in mood disorders. Cellular prion protein (PrPc) is infamous for its potential to convert its insoluble form, leading to neurodegeneration in Creutzfeldt-Jacob disease. Meanwhile, in its physiological state, PrPc presents neuroprotective features and regulates neurotransmission and synaptic plasticity. The aim of this study is to integrate the available knowledge about molecular mechanisms underlying the impact of PrPc on the pathophysiology of mood disorders. Our review indicates an important role of this protein in regulation of cognitive functions, emotions, sleep and biological rhythms, and its deficiency results in depressive-like behavior and cognitive impairment. PrPc plays a neuroprotective role against excitotoxicity, oxidative stress and inflammation, the main pathophysiological events in the course of mood disorders. Research indicates that PrPc may be a promising biomarker of cognitive decline. There is an urgent need of human studies to elucidate its potential utility in clinical practice.
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Affiliation(s)
- Adrian Andrzej Chrobak
- Department of Adult Psychiatry, Jagiellonian University Medical College, Kopernika 21A, 31-501 Kraków, Poland; (A.A.C.); (P.K.); (D.D.)
| | - Patrycja Pańczyszyn-Trzewik
- Department of Human Physiology, Institute of Medical Sciences, Medical College of Rzeszow University, Kopisto 2a, 35-959 Rzeszow, Poland;
| | - Patrycja Król
- Department of Adult Psychiatry, Jagiellonian University Medical College, Kopernika 21A, 31-501 Kraków, Poland; (A.A.C.); (P.K.); (D.D.)
| | - Magdalena Pawelec-Bąk
- Department of Affective Disorders, Jagiellonian University Medical College, Kopernika 21A, 31-501 Kraków, Poland;
| | - Dominika Dudek
- Department of Adult Psychiatry, Jagiellonian University Medical College, Kopernika 21A, 31-501 Kraków, Poland; (A.A.C.); (P.K.); (D.D.)
| | - Marcin Siwek
- Department of Affective Disorders, Jagiellonian University Medical College, Kopernika 21A, 31-501 Kraków, Poland;
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2
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Grimaldi I, Leser FS, Janeiro JM, da Rosa BG, Campanelli AC, Romão L, Lima FRS. The multiple functions of PrP C in physiological, cancer, and neurodegenerative contexts. J Mol Med (Berl) 2022; 100:1405-1425. [PMID: 36056255 DOI: 10.1007/s00109-022-02245-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 08/05/2022] [Accepted: 08/09/2022] [Indexed: 11/29/2022]
Abstract
Cellular prion protein (PrPC) is a highly conserved glycoprotein, present both anchored in the cell membrane and soluble in the extracellular medium. It has a diversity of ligands and is variably expressed in numerous tissues and cell subtypes, most notably in the central nervous system (CNS). Its importance has been brought to light over the years both under physiological conditions, such as embryogenesis and immune system homeostasis, and in pathologies, such as cancer and neurodegenerative diseases. During development, PrPC plays an important role in CNS, participating in axonal growth and guidance and differentiation of glial cells, but also in other organs such as the heart, lung, and digestive system. In diseases, PrPC has been related to several types of tumors, modulating cancer stem cells, enhancing malignant properties, and inducing drug resistance. Also, in non-neoplastic diseases, such as Alzheimer's and Parkinson's diseases, PrPC seems to alter the dynamics of neurotoxic aggregate formation and, consequently, the progression of the disease. In this review, we explore in detail the multiple functions of this protein, which proved to be relevant for understanding the dynamics of organism homeostasis, as well as a promising target in the treatment of both neoplastic and degenerative diseases.
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Affiliation(s)
- Izabella Grimaldi
- Glial Cell Biology Laboratory, Biomedical Sciences Institute, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Felipe Saceanu Leser
- Glial Cell Biology Laboratory, Biomedical Sciences Institute, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - José Marcos Janeiro
- Glial Cell Biology Laboratory, Biomedical Sciences Institute, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Bárbara Gomes da Rosa
- Glial Cell Biology Laboratory, Biomedical Sciences Institute, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Ana Clara Campanelli
- Glial Cell Biology Laboratory, Biomedical Sciences Institute, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Luciana Romão
- Cell Morphogenesis Laboratory, Biomedical Sciences Institute, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Flavia Regina Souza Lima
- Glial Cell Biology Laboratory, Biomedical Sciences Institute, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
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3
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Matamoros-Angles A, Hervera A, Soriano J, Martí E, Carulla P, Llorens F, Nuvolone M, Aguzzi A, Ferrer I, Gruart A, Delgado-García JM, Del Río JA. Analysis of co-isogenic prion protein deficient mice reveals behavioral deficits, learning impairment, and enhanced hippocampal excitability. BMC Biol 2022; 20:17. [PMID: 35027047 PMCID: PMC8759182 DOI: 10.1186/s12915-021-01203-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 12/02/2021] [Indexed: 12/22/2022] Open
Abstract
Background Cellular prion protein (PrPC) is a cell surface GPI-anchored protein, usually known for its role in the pathogenesis of human and animal prionopathies. However, increasing knowledge about the participation of PrPC in prion pathogenesis contrasts with puzzling data regarding its natural physiological role. PrPC is expressed in a number of tissues, including at high levels in the nervous system, especially in neurons and glial cells, and while previous studies have established a neuroprotective role, conflicting evidence for a synaptic function has revealed both reduced and enhanced long-term potentiation, and variable observations on memory, learning, and behavior. Such evidence has been confounded by the absence of an appropriate knock-out mouse model to dissect the biological relevance of PrPC, with some functions recently shown to be misattributed to PrPC due to the presence of genetic artifacts in mouse models. Here we elucidate the role of PrPC in the hippocampal circuitry and its related functions, such as learning and memory, using a recently available strictly co-isogenic Prnp0/0 mouse model (PrnpZH3/ZH3). Results We performed behavioral and operant conditioning tests to evaluate memory and learning capabilities, with results showing decreased motility, impaired operant conditioning learning, and anxiety-related behavior in PrnpZH3/ZH3 animals. We also carried in vivo electrophysiological recordings on CA3-CA1 synapses in living behaving mice and monitored spontaneous neuronal firing and network formation in primary neuronal cultures of PrnpZH3/ZH3 vs wildtype mice. PrPC absence enhanced susceptibility to high-intensity stimulations and kainate-induced seizures. However, long-term potentiation (LTP) was not enhanced in the PrnpZH3/ZH3 hippocampus. In addition, we observed a delay in neuronal maturation and network formation in PrnpZH3/ZH3 cultures. Conclusion Our results demonstrate that PrPC promotes neuronal network formation and connectivity. PrPC mediates synaptic function and protects the synapse from excitotoxic insults. Its deletion may underlie an epileptogenic-susceptible brain that fails to perform highly cognitive-demanding tasks such as associative learning and anxiety-like behaviors. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-021-01203-0.
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Affiliation(s)
- A Matamoros-Angles
- Molecular and Cellular Neurobiotechnology, Institute of Bioengineering of Catalonia (IBEC), Parc Científic de Barcelona, Barcelona, Spain.,Department of Cell Biology, Physiology, and Immunology, University of Barcelona, Barcelona, Spain.,CIBERNED (Network Centre of Biomedical Research of Neurodegenerative Diseases), Institute of Health Carlos III, Barcelona, Spain.,Institute of Neuroscience, University of Barcelona, Barcelona, Spain.,Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - A Hervera
- Molecular and Cellular Neurobiotechnology, Institute of Bioengineering of Catalonia (IBEC), Parc Científic de Barcelona, Barcelona, Spain.,Department of Cell Biology, Physiology, and Immunology, University of Barcelona, Barcelona, Spain.,CIBERNED (Network Centre of Biomedical Research of Neurodegenerative Diseases), Institute of Health Carlos III, Barcelona, Spain.,Institute of Neuroscience, University of Barcelona, Barcelona, Spain
| | - J Soriano
- Departament de Física de la Materia Condensada, University of Barcelona, Barcelona, Spain.,Institute of Complex Systems (UBICS), University of Barcelona, Barcelona, Spain
| | - E Martí
- Department of Biomedicine, University of Barcelona, Barcelona, Spain.,Bioinformatics and Genomics, Center for Genomic Regulation, Barcelona, Spain
| | - P Carulla
- Molecular and Cellular Neurobiotechnology, Institute of Bioengineering of Catalonia (IBEC), Parc Científic de Barcelona, Barcelona, Spain.,Department of Cell Biology, Physiology, and Immunology, University of Barcelona, Barcelona, Spain.,CIBERNED (Network Centre of Biomedical Research of Neurodegenerative Diseases), Institute of Health Carlos III, Barcelona, Spain
| | - F Llorens
- CIBERNED (Network Centre of Biomedical Research of Neurodegenerative Diseases), Institute of Health Carlos III, Barcelona, Spain.,Department of Neurology, University Medical School, Göttingen, Germany.,Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat, Catalonia, Spain
| | - M Nuvolone
- Institute of Neuropathology, University Hospital of Zürich, Zürich, Switzerland.,Amyloidosis Center, Foundation IRCCS Policlinico San Matteo, Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - A Aguzzi
- Institute of Neuropathology, University Hospital of Zürich, Zürich, Switzerland
| | - I Ferrer
- CIBERNED (Network Centre of Biomedical Research of Neurodegenerative Diseases), Institute of Health Carlos III, Barcelona, Spain.,Institute of Neuroscience, University of Barcelona, Barcelona, Spain.,Senior Consultant, Bellvitge University Hospital, IDIBELL (Bellvitge Biomedical Research Centre), L'Hospitalet de Llobregat, Spain.,Department of Pathology and Experimental Therapeutics, University of Barcelona, Barcelona, Spain
| | - A Gruart
- Division of Neurosciences, Pablo de Olavide University, 41013, Seville, Spain
| | - J M Delgado-García
- Division of Neurosciences, Pablo de Olavide University, 41013, Seville, Spain.
| | - J A Del Río
- Molecular and Cellular Neurobiotechnology, Institute of Bioengineering of Catalonia (IBEC), Parc Científic de Barcelona, Barcelona, Spain. .,Department of Cell Biology, Physiology, and Immunology, University of Barcelona, Barcelona, Spain. .,CIBERNED (Network Centre of Biomedical Research of Neurodegenerative Diseases), Institute of Health Carlos III, Barcelona, Spain. .,Institute of Neuroscience, University of Barcelona, Barcelona, Spain.
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4
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Janner DR, de Lima EV, da Silva RT, Clarke JR, Linden R. Dissociation of genotype-dependent cognitive and motor behavior in a strain of aging mice devoid of the prion protein. Behav Brain Res 2021; 411:113386. [PMID: 34052264 DOI: 10.1016/j.bbr.2021.113386] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 05/02/2021] [Accepted: 05/22/2021] [Indexed: 11/18/2022]
Abstract
The prion glycoprotein (PrPC) is highly expressed in the nervous system as well as in other organs. Its functional roles in behavior have been examined mainly in non co-isogenic, wild-type and PrPC-deficient mice, which showed both age- and genotype-dependent differences. In general, however, effects of genetic background upon behavioral tests are mostly unclear when applied to aging rodents. The present study aimed to determine the effect of deletion of the prion protein on behavior of isogenic mice across different ages. We disclosed a genotype-dependent behavioral dissociation between either motor or cognitive tests, as a function of both age and test type. Remarkably, we also detected a clear age- and genotype-dependent difference in the variability of performance in a cognitive test. The current findings are relevant for both the interpretation of PrPC-related behavior, as well as for issues of reproducibility in studies of rodent behavior.
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Affiliation(s)
- Daiane R Janner
- Instituto de Biofísica Carlos Chagas Filho, UFRJ, RJ, Brazil.
| | | | | | | | - Rafael Linden
- Instituto de Biofísica Carlos Chagas Filho, UFRJ, RJ, Brazil.
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5
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Prediger RD, Schamne MG, Sampaio TB, Moreira ELG, Rial D. Animal models of olfactory dysfunction in neurodegenerative diseases. HANDBOOK OF CLINICAL NEUROLOGY 2019; 164:431-452. [PMID: 31604561 DOI: 10.1016/b978-0-444-63855-7.00024-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Olfactory dysfunction seems to occur earlier than classic motor and cognitive symptoms in many neurodegenerative diseases, including Parkinson's disease (PD) and Alzheimer's disease (AD). Thus, the use of the olfactory system as a clinical marker for neurodegenerative diseases is helpful in the characterization of prodromal stages of these diseases, early diagnostic strategies, differential diagnosis, and, potentially, prediction of treatment success. The use of genetic and neurotoxin animal models has contributed to the understanding of the mechanisms underlying olfactory dysfunction in a number of neurodegenerative diseases. In this chapter, we provide an overview of behavioral and neurochemical alterations observed in animal models of different neurodegenerative diseases (such as genetic and Aβ infusion models for AD and neurotoxins and genetic models of PD), in which olfactory dysfunction has been described.
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Affiliation(s)
- Rui D Prediger
- Department of Pharmacology, Center of Biological Sciences, Federal University of Santa Catarina, Florianópolis, Brazil.
| | - Marissa G Schamne
- Department of Pharmacology, Center of Biological Sciences, Federal University of Santa Catarina, Florianópolis, Brazil
| | - Tuane B Sampaio
- Department of Pharmacology, Center of Biological Sciences, Federal University of Santa Catarina, Florianópolis, Brazil
| | - Eduardo L G Moreira
- Department of Physiological Sciences, Center of Biological Sciences¸ Federal University of Santa Catarina, Florianópolis, Brazil
| | - Daniel Rial
- Department of Pharmacology, Center of Biological Sciences, Federal University of Santa Catarina, Florianópolis, Brazil
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6
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Salvesen Ø, Tatzelt J, Tranulis MA. The prion protein in neuroimmune crosstalk. Neurochem Int 2018; 130:104335. [PMID: 30448564 DOI: 10.1016/j.neuint.2018.11.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 10/04/2018] [Accepted: 11/14/2018] [Indexed: 01/11/2023]
Abstract
The cellular prion protein (PrPC) is a medium-sized glycoprotein, attached to the cell surface by a glycosylphosphatidylinositol anchor. PrPC is encoded by a single-copy gene, PRNP, which is abundantly expressed in the central nervous system and at lower levels in non-neuronal cells, including those of the immune system. Evidence from experimental knockout of PRNP in rodents, goats, and cattle and the occurrence of a nonsense mutation in goat that prevents synthesis of PrPC, have shown that the molecule is non-essential for life. Indeed, no easily recognizable phenotypes are associate with a lack of PrPC, except the potentially advantageous trait that animals without PrPC cannot develop prion disease. This is because, in prion diseases, PrPC converts to a pathogenic "scrapie" conformer, PrPSc, which aggregates and eventually induces neurodegeneration. In addition, endogenous neuronal PrPC serves as a toxic receptor to mediate prion-induced neurotoxicity. Thus, PrPC is an interesting target for treatment of prion diseases. Although loss of PrPC has no discernable effect, alteration of its normal physiological function can have very harmful consequences. It is therefore important to understand cellular processes involving PrPC, and research of this topic has advanced considerably in the past decade. Here, we summarize data that indicate the role of PrPC in modulating immune signaling, with emphasis on neuroimmune crosstalk both under basal conditions and during inflammatory stress.
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Affiliation(s)
- Øyvind Salvesen
- Faculty of Veterinary Medicine, Department of Production Animal Clinical Sciences, Norwegian University of Life Sciences, Sandnes, Norway.
| | - Jörg Tatzelt
- Department Biochemistry of Neurodegenerative Diseases, Institute of Biochemistry and Pathobiochemistry, Ruhr University Bochum, Germany.
| | - Michael A Tranulis
- Faculty of Veterinary Medicine, Department of Basic Sciences and Aquatic Medicine, Norwegian University of Life Sciences, Oslo, Norway.
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7
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Leighton PLA, Nadolski NJ, Morrill A, Hamilton TJ, Allison WT. An ancient conserved role for prion protein in learning and memory. Biol Open 2018; 7:bio.025734. [PMID: 29358166 PMCID: PMC5829491 DOI: 10.1242/bio.025734] [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] [Indexed: 12/19/2022] Open
Abstract
The misfolding of cellular prion protein (PrPC) to form PrP Scrapie (PrPSc) is an exemplar of toxic gain-of-function mechanisms inducing propagated protein misfolding and progressive devastating neurodegeneration. Despite this, PrPC function in the brain is also reduced and subverted during prion disease progression; thus understanding the normal function of PrPC in healthy brains is key. Disrupting PrPC in mice has led to a myriad of controversial functions that sometimes map onto disease symptoms, including a proposed role in memory or learning. Intriguingly, PrPC interaction with amyloid beta (Aβ) oligomers at synapses has also linked its function to Alzheimer's disease and dementia in recent years. We set out to test the involvement of PrPC in memory using a disparate animal model, the zebrafish. Here we document an age-dependent memory decline in prp2−/− zebrafish, pointing to a conserved and ancient role of PrPC in memory. Specifically, we found that aged (3-year-old) prp2−/− fish performed poorly in an object recognition task relative to age-matched prp2+/+ fish or 1-year-old prp2−/− fish. Further, using a novel object approach (NOA) test, we found that aged (3-year-old) prp2−/− fish approached the novel object more than either age-matched prp2+/+ fish or 1-year-old prp2−/− fish, but did not have decreased anxiety when we tested them in a novel tank diving test. Taken together, the results of the NOA and novel tank diving tests suggest an altered cognitive appraisal of the novel object in the 3-year-old prp2−/− fish. The learning paradigm established here enables a path forward to study PrPC interactions of relevance to Alzheimer's disease and prion diseases, and to screen for candidate therapeutics for these diseases. The findings underpin a need to consider the relative contributions of loss- versus gain-of-function of PrPC during Alzheimer's and prion diseases, and have implications upon the prospects of several promising therapeutic strategies. Summary: Prion protein dysfunction at the synapse impacts learning in Alzheimer disease. Here, we demonstrate similar roles for prion protein in zebrafish, revealing ancient constructive roles for this infamously toxic protein.
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Affiliation(s)
- Patricia L A Leighton
- Centre for Prions and Protein Folding Disease, University of Alberta, Edmonton, AB T6G 2M8, Canada.,Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Nathan J Nadolski
- Department of Psychology, MacEwan University, Edmonton, AB T5J 4S2, Canada
| | - Adam Morrill
- Department of Psychology, MacEwan University, Edmonton, AB T5J 4S2, Canada
| | - Trevor J Hamilton
- Department of Psychology, MacEwan University, Edmonton, AB T5J 4S2, Canada .,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB T6G 2E1
| | - W Ted Allison
- Centre for Prions and Protein Folding Disease, University of Alberta, Edmonton, AB T6G 2M8, Canada .,Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada.,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB T6G 2E1.,Department of Medical Genetics, University of Alberta, Edmonton, AB T6G 2H7, Canada
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8
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Hirsch TZ, Martin-Lannerée S, Mouillet-Richard S. Functions of the Prion Protein. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2017; 150:1-34. [PMID: 28838656 DOI: 10.1016/bs.pmbts.2017.06.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Although initially disregarded compared to prion pathogenesis, the functions exerted by the cellular prion protein PrPC have gained much interest over the past two decades. Research aiming at unraveling PrPC functions started to intensify when it became appreciated that it would give clues as to how it is subverted in the context of prion infection and, more recently, in the context of Alzheimer's disease. It must now be admitted that PrPC is implicated in an incredible variety of biological processes, including neuronal homeostasis, stem cell fate, protection against stress, or cell adhesion. It appears that these diverse roles can all be fulfilled through the involvement of PrPC in cell signaling events. Our aim here is to provide an overview of our current understanding of PrPC functions from the animal to the molecular scale and to highlight some of the remaining gaps that should be addressed in future research.
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Affiliation(s)
- Théo Z Hirsch
- INSERM UMR 1124, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, UMR 1124, Paris, France
| | - Séverine Martin-Lannerée
- INSERM UMR 1124, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, UMR 1124, Paris, France
| | - Sophie Mouillet-Richard
- INSERM UMR 1124, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, UMR 1124, Paris, France.
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9
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Castle AR, Gill AC. Physiological Functions of the Cellular Prion Protein. Front Mol Biosci 2017; 4:19. [PMID: 28428956 PMCID: PMC5382174 DOI: 10.3389/fmolb.2017.00019] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 03/22/2017] [Indexed: 01/09/2023] Open
Abstract
The prion protein, PrPC, is a small, cell-surface glycoprotein notable primarily for its critical role in pathogenesis of the neurodegenerative disorders known as prion diseases. A hallmark of prion diseases is the conversion of PrPC into an abnormally folded isoform, which provides a template for further pathogenic conversion of PrPC, allowing disease to spread from cell to cell and, in some circumstances, to transfer to a new host. In addition to the putative neurotoxicity caused by the misfolded form(s), loss of normal PrPC function could be an integral part of the neurodegenerative processes and, consequently, significant research efforts have been directed toward determining the physiological functions of PrPC. In this review, we first summarise important aspects of the biochemistry of PrPC before moving on to address the current understanding of the various proposed functions of the protein, including details of the underlying molecular mechanisms potentially involved in these functions. Over years of study, PrPC has been associated with a wide array of different cellular processes and many interacting partners have been suggested. However, recent studies have cast doubt on the previously well-established links between PrPC and processes such as stress-protection, copper homeostasis and neuronal excitability. Instead, the functions best-supported by the current literature include regulation of myelin maintenance and of processes linked to cellular differentiation, including proliferation, adhesion, and control of cell morphology. Intriguing connections have also been made between PrPC and the modulation of circadian rhythm, glucose homeostasis, immune function and cellular iron uptake, all of which warrant further investigation.
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10
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Peggion C, Bertoli A, Sorgato MC. Almost a century of prion protein(s): From pathology to physiology, and back to pathology. Biochem Biophys Res Commun 2016; 483:1148-1155. [PMID: 27581199 DOI: 10.1016/j.bbrc.2016.07.118] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 07/27/2016] [Indexed: 12/30/2022]
Abstract
Prions are one of the few pathogens whose name is renowned at all population levels, after the dramatic years pervaded by the fear of eating prion-infected food. If now this, somehow irrational, scare of bovine meat inexorably transmitting devastating brain disorders is largely subdued, several prion-related issues are still unsolved, precluding the design of therapeutic approaches that could slow, if not halt, prion diseases. One unsolved issue is, for example, the role of the prion protein (PrPC), whole conformational misfolding originates the prion but whose physiologic reason d'etre in neurons, and in cells at large, remains enigmatic. Preceded by a historical outline, the present review will discuss the functional pleiotropicity ascribed to PrPC, and whether this aspect could fall, at least in part, into a more concise framework. It will also be devoted to radically different perspectives for PrPC, which have been recently brought to the attention of the scientific world with unexpected force. Finally, it will discuss the possible reasons allowing an evolutionary conserved and benign protein, as PrPC is, to turn into a high affinity receptor for pathologic misfolded oligomers, and to transmit their toxic message into neurons.
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Affiliation(s)
- Caterina Peggion
- Department of Biomedical Sciences, University of Padova, Via Bassi 58/B, 35131 Padova, Italy.
| | - Alessandro Bertoli
- Department of Biomedical Sciences, University of Padova, Via Bassi 58/B, 35131 Padova, Italy
| | - M Catia Sorgato
- Department of Biomedical Sciences, University of Padova, Via Bassi 58/B, 35131 Padova, Italy; C.N.R. Institute of Neuroscience, University of Padova, Via Bassi 58/B, 35131 Padova, Italy.
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11
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Massimino ML, Peggion C, Loro F, Stella R, Megighian A, Scorzeto M, Blaauw B, Toniolo L, Sorgato MC, Reggiani C, Bertoli A. Age-dependent neuromuscular impairment in prion protein knockout mice. Muscle Nerve 2015; 53:269-79. [DOI: 10.1002/mus.24708] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/13/2015] [Indexed: 12/26/2022]
Affiliation(s)
| | - Caterina Peggion
- Department of Biomedical Sciences; University of Padova; Via U. Bassi 58/B 35131 Padova Italy
| | - Federica Loro
- Department of Biomedical Sciences; University of Padova; Via U. Bassi 58/B 35131 Padova Italy
| | - Roberto Stella
- Department of Biomedical Sciences; University of Padova; Via U. Bassi 58/B 35131 Padova Italy
| | - Aram Megighian
- Department of Biomedical Sciences; University of Padova; Via U. Bassi 58/B 35131 Padova Italy
| | - Michele Scorzeto
- Department of Biomedical Sciences; University of Padova; Via U. Bassi 58/B 35131 Padova Italy
| | - Bert Blaauw
- Department of Biomedical Sciences; University of Padova; Via U. Bassi 58/B 35131 Padova Italy
| | - Luana Toniolo
- Department of Biomedical Sciences; University of Padova; Via U. Bassi 58/B 35131 Padova Italy
| | - Maria Catia Sorgato
- CNR Neuroscience Institute, University of Padova
- Department of Biomedical Sciences; University of Padova; Via U. Bassi 58/B 35131 Padova Italy
| | - Carlo Reggiani
- CNR Neuroscience Institute, University of Padova
- Department of Biomedical Sciences; University of Padova; Via U. Bassi 58/B 35131 Padova Italy
| | - Alessandro Bertoli
- Department of Biomedical Sciences; University of Padova; Via U. Bassi 58/B 35131 Padova Italy
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12
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Schmitz M, Zafar S, Silva CJ, Zerr I. Behavioral abnormalities in prion protein knockout mice and the potential relevance of PrP(C) for the cytoskeleton. Prion 2015; 8:381-6. [PMID: 25517431 DOI: 10.4161/19336896.2014.983746] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The cellular prion protein (PrP(C)) is a highly conserved protein, which is anchored to the outer surface of the plasma membrane. Even though its physiological function has already been investigated in different cell or mouse models where PrP(C) expression is either upregulated or depleted, its exact physiological role in a mammalian organism remains elusive. Recent studies indicate that PrP(C) has multiple functions and is involved in cognition, learning, anxiety, locomotion, depression, offensive aggression and nest building behavior. While young animals (3 months of age) show only marginal abnormalities, most of the deficits become apparent as the animals age, which might indicate its role in neurodegeneration or neuroprotection. However, the exact biochemical mechanism and signal transduction pathways involving PrP(C) are only gradually becoming clearer. We report the observations made in different studies using different Prnp0/0 mouse models and propose that PrP(C) plays an important role in the regulation of the cytoskeleton and associated proteins. In particular, we showed a nocodazole treatment influenced colocalization of PrP(C) and α tubulin 1. In addition, we confirmed the observed deficits in nest building using a different backcrossed Prnp0/0 mouse line.
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Affiliation(s)
- Matthias Schmitz
- a Department of Neurology ; University Medical Center Göttingen, and German Center for Neurodegenerative Diseases (DZNE) ; Göttingen , Germany
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Gonçalves FQ, Pires J, Pliassova A, Beleza R, Lemos C, Marques JM, Rodrigues RJ, Canas PM, Köfalvi A, Cunha RA, Rial D. Adenosine A2b receptors control A1 receptor-mediated inhibition of synaptic transmission in the mouse hippocampus. Eur J Neurosci 2015; 41:878-88. [PMID: 25704806 DOI: 10.1111/ejn.12851] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 12/29/2014] [Accepted: 01/14/2015] [Indexed: 01/21/2023]
Abstract
Adenosine is a neuromodulator mostly acting through A1 (inhibitory) and A2A (excitatory) receptors in the brain. A2B receptors (A(2B)R) are G(s/q)--protein-coupled receptors with low expression in the brain. As A(2B)R function is largely unknown, we have now explored their role in the mouse hippocampus. We performed electrophysiological extracellular recordings in mouse hippocampal slices, and immunological analysis of nerve terminals and glutamate release in hippocampal slices and synaptosomes. Additionally, A(2B)R-knockout (A(2B)R-KO) and C57/BL6 mice were submitted to a behavioural test battery (open field, elevated plus-maze, Y-maze). The A(2B)R agonist BAY60-6583 (300 nM) decreased the paired-pulse stimulation ratio, an effect prevented by the A(2B)R antagonist MRS 1754 (200 nM) and abrogated in A(2B)R-KO mice. Accordingly, A(2B)R immunoreactivity was present in 73 ± 5% of glutamatergic nerve terminals, i.e. those immunopositive for vesicular glutamate transporters. Furthermore, BAY 60-6583 attenuated the A(1)R control of synaptic transmission, both the A(1)R inhibition caused by 2-chloroadenosine (0.1-1 μM) and the disinhibition caused by the A(1)R antagonist DPCPX (100 nM), both effects prevented by MRS 1754 and abrogated in A(2B)R-KO mice. BAY 60-6583 decreased glutamate release in slices and also attenuated the A(1)R inhibition (CPA 100 nM). A(2B)R-KO mice displayed a modified exploratory behaviour with an increased time in the central areas of the open field, elevated plus-maze and the Y-maze and no alteration of locomotion, anxiety or working memory. We conclude that A(2B)R are present in hippocampal glutamatergic terminals where they counteract the predominant A(1)R-mediated inhibition of synaptic transmission, impacting on exploratory behaviour.
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Affiliation(s)
- Francisco Q Gonçalves
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517, Coimbra, Portugal
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Halliez S, Passet B, Martin-Lannerée S, Hernandez-Rapp J, Laude H, Mouillet-Richard S, Vilotte JL, Béringue V. To develop with or without the prion protein. Front Cell Dev Biol 2014; 2:58. [PMID: 25364763 PMCID: PMC4207017 DOI: 10.3389/fcell.2014.00058] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 09/22/2014] [Indexed: 12/23/2022] Open
Abstract
The deletion of the cellular form of the prion protein (PrPC) in mouse, goat, and cattle has no drastic phenotypic consequence. This stands in apparent contradiction with PrPC quasi-ubiquitous expression and conserved primary and tertiary structures in mammals, and its pivotal role in neurodegenerative diseases such as prion and Alzheimer's diseases. In zebrafish embryos, depletion of PrP ortholog leads to a severe loss-of-function phenotype. This raises the question of a potential role of PrPC in the development of all vertebrates. This view is further supported by the early expression of the PrPC encoding gene (Prnp) in many tissues of the mouse embryo, the transient disruption of a broad number of cellular pathways in early Prnp−/− mouse embryos, and a growing body of evidence for PrPC involvement in the regulation of cell proliferation and differentiation in various types of mammalian stem cells and progenitors. Finally, several studies in both zebrafish embryos and in mammalian cells and tissues in formation support a role for PrPC in cell adhesion, extra-cellular matrix interactions and cytoskeleton. In this review, we summarize and compare the different models used to decipher PrPC functions at early developmental stages during embryo- and organo-genesis and discuss their relevance.
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Affiliation(s)
- Sophie Halliez
- Institut National de la Recherche Agronomique, U892 Virologie et Immunologie Moléculaires Jouy-en-Josas, France
| | - Bruno Passet
- Institut National de la Recherche Agronomique, UMR1313 Génétique Animale et Biologie Intégrative Jouy-en-Josas, France
| | - Séverine Martin-Lannerée
- Institut National de la Santé et de la Recherche Médicale, UMR-S1124 Paris, France ; Université Paris Descartes, Sorbonne Paris Cité, UMR-S1124 Paris, France
| | - Julia Hernandez-Rapp
- Institut National de la Santé et de la Recherche Médicale, UMR-S1124 Paris, France ; Université Paris Descartes, Sorbonne Paris Cité, UMR-S1124 Paris, France
| | - Hubert Laude
- Institut National de la Recherche Agronomique, U892 Virologie et Immunologie Moléculaires Jouy-en-Josas, France
| | - Sophie Mouillet-Richard
- Institut National de la Santé et de la Recherche Médicale, UMR-S1124 Paris, France ; Université Paris Descartes, Sorbonne Paris Cité, UMR-S1124 Paris, France
| | - Jean-Luc Vilotte
- Institut National de la Recherche Agronomique, UMR1313 Génétique Animale et Biologie Intégrative Jouy-en-Josas, France
| | - Vincent Béringue
- Institut National de la Recherche Agronomique, U892 Virologie et Immunologie Moléculaires Jouy-en-Josas, France
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15
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Ganzinger KA, Narayan P, Qamar SS, Weimann L, Ranasinghe RT, Aguzzi A, Dobson CM, McColl J, St George-Hyslop P, Klenerman D. Single-molecule imaging reveals that small amyloid-β1-42 oligomers interact with the cellular prion protein (PrP(C)). Chembiochem 2014; 15:2515-21. [PMID: 25294384 PMCID: PMC4371635 DOI: 10.1002/cbic.201402377] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Indexed: 12/17/2022]
Abstract
Oligomers of the amyloid-β peptide (Aβ) play a central role in the pathogenesis of Alzheimer’s disease and have been suggested to induce neurotoxicity by binding to a plethora of cell-surface receptors. However, the heterogeneous mixtures of oligomers of varying sizes and conformations formed by Aβ42 have obscured the nature of the oligomeric species that bind to a given receptor. Here, we have used single-molecule imaging to characterize Aβ42 oligomers (oAβ42) and to confirm the controversial interaction of oAβ42 with the cellular prion protein (PrPC) on live neuronal cells. Our results show that, at nanomolar concentrations, oAβ42 interacts with PrPC and that the species bound to PrPC are predominantly small oligomers (dimers and trimers). Single-molecule biophysical studies can thus aid in deciphering the mechanisms that underlie receptor-mediated oAβ-induced neurotoxicity, and ultimately facilitate the discovery of novel inhibitors of these pathways.
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Affiliation(s)
- Kristina A Ganzinger
- Department of Chemistry, University of CambridgeLensfield Road, Cambridge, CB2 1EW (UK)
| | - Priyanka Narayan
- Present address: Whitehead Institute for Biomedical Research9 Cambridge Center, Cambridge, MA 02142 (USA)
| | - Seema S Qamar
- Department of Clinical Neurosciences, Cambridge Institute for Medical Research, University of CambridgeCambridge CB2 0XY (UK)
| | - Laura Weimann
- Department of Chemistry, University of CambridgeLensfield Road, Cambridge, CB2 1EW (UK)
| | - Rohan T Ranasinghe
- Department of Chemistry, University of CambridgeLensfield Road, Cambridge, CB2 1EW (UK)
| | - Adriano Aguzzi
- UniversitätsSpital Zürich, Institut für NeuropathologieSchmelzbergstrasse 12, 8091 Zürich (Switzerland)
| | - Christopher M Dobson
- Department of Chemistry, University of CambridgeLensfield Road, Cambridge, CB2 1EW (UK)
| | - James McColl
- Present address: School of Biological Sciences, University of East AngliaNorwich Research Park, Norwich NR4 7TJ (UK)
- James McColl, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW (UK), Peter St. George-Hyslop, Department of Clinical Neurosciences, Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY (UK), David Klenerman, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW (UK) E-mail: E-mail:
| | - Peter St George-Hyslop
- Department of Clinical Neurosciences, Cambridge Institute for Medical Research, University of CambridgeCambridge CB2 0XY (UK)
- James McColl, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW (UK), Peter St. George-Hyslop, Department of Clinical Neurosciences, Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY (UK), David Klenerman, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW (UK) E-mail: E-mail:
| | - David Klenerman
- Department of Chemistry, University of CambridgeLensfield Road, Cambridge, CB2 1EW (UK)
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Cellular prion protein (PrPC) modulates ethanol-induced behavioral adaptive changes in mice. Behav Brain Res 2014; 271:325-32. [DOI: 10.1016/j.bbr.2014.05.067] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 05/28/2014] [Accepted: 05/31/2014] [Indexed: 12/29/2022]
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Abstract
The cellular prion protein (PrPC) has been widely investigated ever since its conformational isoform, the prion (or PrPSc), was identified as the etiological agent of prion disorders. The high homology shared by the PrPC-encoding gene among mammals, its high turnover rate and expression in every tissue strongly suggest that PrPC may possess key physiological functions. Therefore, defining PrPC roles, properties and fate in the physiology of mammalian cells would be fundamental to understand its pathological involvement in prion diseases. Since the incidence of these neurodegenerative disorders is enhanced in aging, understanding PrPC functions in this life phase may be of crucial importance. Indeed, a large body of evidence suggests that PrPC plays a neuroprotective and antioxidant role. Moreover, it has been suggested that PrPC is involved in Alzheimer disease, another neurodegenerative pathology that develops predominantly in the aging population. In prion diseases, PrPC function is likely lost upon protein aggregation occurring in the course of the disease. Additionally, the aging process may alter PrPC biochemical properties, thus influencing its propensity to convert into PrPSc. Both phenomena may contribute to the disease development and progression. In Alzheimer disease, PrPC has a controversial role because its presence seems to mediate β-amyloid toxicity, while its down-regulation correlates with neuronal death. The role of PrPC in aging has been investigated from different perspectives, often leading to contrasting results. The putative protein functions in aging have been studied in relation to memory, behavior and myelin maintenance. In aging mice, PrPC changes in subcellular localization and post-translational modifications have been explored in an attempt to relate them to different protein roles and propensity to convert into PrPSc. Here we provide an overview of the most relevant studies attempting to delineate PrPC functions and fate in aging.
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Affiliation(s)
- Lisa Gasperini
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati Trieste, Italy
| | - Giuseppe Legname
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati Trieste, Italy
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Schmitz AE, de Oliveira PA, de Souza LF, da Silva DGH, Danielski S, Santos DB, de Almeida EA, Prediger RD, Fisher A, Farina M, Dafre AL. Interaction of curcumin with manganese may compromise metal and neurotransmitter homeostasis in the hippocampus of young mice. Biol Trace Elem Res 2014; 158:399-409. [PMID: 24723215 DOI: 10.1007/s12011-014-9951-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Accepted: 03/17/2014] [Indexed: 11/26/2022]
Abstract
Manganese (Mn) exposure is related to industrial activities, where absorption by inhalation has high relevance. Manganism, a syndrome caused as a result of excessive accumulation of Mn in the central nervous system, has numerous symptoms similar to those seen in idiopathic Parkinson disease (IPD). Some of these symptoms, such as learning, memory, sensorial, and neurochemical changes, appear before the onset of motor deficits in both manganism and IPD. The aim of this study was to evaluate the possible neuroprotective effects of curcumin against behavioral deficits induced by Mn toxicity in young (2 months old) Swiss mice. We evaluated the effect of chronic inhalation of a Mn mixture [Mn(OAc)3 and MnCl2 (20:40 mM)], 1 h/session, three times a week, over a 14-week period on behavioral and neurochemical parameters. Curcumin was supplemented in the diet (500 or 1,500 ppm in food pellets). The Mn disrupted the motor performance evaluated in the single-pellet reach task, as well as the short- and long-term spatial memory evaluated in the step-down inhibitory avoidance task. Surprisingly, curcumin also produced similar deleterious effects in such behavioral tests. Moreover, the association of Mn plus curcumin significantly increased the levels of Mn and iron, and decreased the levels of dopamine and serotonin in the hippocampus. These alterations were not observed in the striatum. In conclusion, the current Mn treatment protocol resulted in mild deficits in motor and memory functions, resembling the early phases of IPD. Additionally, curcumin showed no beneficial effects against Mn-induced disruption of hippocampal metal and neurotransmitter homeostasis.
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Affiliation(s)
- Ariana Ern Schmitz
- Department of Biochemistry, Federal University of Santa Catarina, Biological Sciences Centre, 88040-900, Florianópolis, SC, Brazil
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Rial D, Pamplona FA, Moreira ELG, Moreira KM, Hipolide D, Rodrigues DI, Dombrowski PA, Da Cunha C, Agostinho P, Takahashi RN, Walz R, Cunha RA, Prediger RD. Cellular prion protein is present in dopaminergic neurons and modulates the dopaminergic system. Eur J Neurosci 2014; 40:2479-86. [PMID: 24766164 DOI: 10.1111/ejn.12600] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 03/12/2014] [Accepted: 03/27/2014] [Indexed: 01/27/2023]
Abstract
Cellular prion protein (PrP(C) ) is widely expressed in the brain. Although the precise role of PrP(C) remains uncertain, it has been proposed to be a pivotal modulator of neuroplasticity events by regulating the glutamatergic and serotonergic systems. Here we report the existence of neurochemical and functional interactions between PrP(C) and the dopaminergic system. PrP(C) was found to co-localize with dopaminergic neurons and in dopaminergic synapses in the striatum. Furthermore, the genetic deletion of PrP(C) down-regulated dopamine D1 receptors and DARPP-32 density in the striatum and decreased dopamine levels in the prefrontal cortex of mice. This indicates that PrP(C) affects the homeostasis of the dopaminergic system by interfering differently in different brain areas with dopamine synthesis, content, receptor density and signaling pathways. This interaction between PrP(C) and the dopaminergic system prompts the hypotheses that the dopaminergic system may be implicated in some pathological features of prion-related diseases and, conversely, that PrP(C) may play a role in dopamine-associated brain disorders.
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Affiliation(s)
- Daniel Rial
- Departamento de Farmacologia, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, UFSC, Florianópolis, Brazil; Center for Neuroscience and Cell Biology, Faculty of Medicine, Rua Larga University of Coimbra, 3004-504 Coimbra, Portugal
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20
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Loss of prion protein leads to age-dependent behavioral abnormalities and changes in cytoskeletal protein expression. Mol Neurobiol 2014; 50:923-36. [PMID: 24604355 DOI: 10.1007/s12035-014-8655-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 01/29/2014] [Indexed: 12/13/2022]
Abstract
The cellular prion protein (PrPC) is a highly conserved protein whose exact physiological role remains elusive. In the present study, we investigated age-dependent behavioral abnormalities in PrPC-knockout (Prnp0/0) mice and wild-type (WT) controls. Prnp0/0 mice showed age-dependent behavioral deficits in memory performance, associative learning, basal anxiety, and nest building behavior. Using a hypothesis-free quantitative proteomic investigation, we found that loss of PrPC affected the levels of neurofilament proteins in an age-dependent manner. In order to understand the biochemical basis of these observations, we analyzed the phosphorylation status of neurofilament heavy chain (NF-H). We found a reduction in NF-H phosphorylation in both Prnp0/0 mice and in PrPC-deficient cells. The expression of Fyn and phospho-Fyn, a potential regulator for NF phosphorylation, was associated with PrPC ablation. The number of β-tubulin III-positive neurons in the hippocampus was diminished in Prnp0/0 mice relative to WT mice. These data indicate that PrPC plays an important role in cytoskeletal organization, brain function, and age-related neuroprotection. Our work represents the first direct biochemical link between these proteins and the observed behavioral phenotypes.
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21
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Bobkova NV, Medvinskaya NI, Kamynina AV, Aleksandrova IY, Nesterova IV, Samokhin AN, Koroev DO, Filatova MP, Nekrasov PV, Abramov AY, Leonov SV, Volpina OM. Immunization with either prion protein fragment 95-123 or the fragment-specific antibodies rescue memory loss and neurodegenerative phenotype of neurons in olfactory bulbectomized mice. Neurobiol Learn Mem 2013; 107:50-64. [PMID: 24239620 DOI: 10.1016/j.nlm.2013.10.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Revised: 09/17/2013] [Accepted: 10/25/2013] [Indexed: 12/12/2022]
Abstract
Epidemiological studies demonstrated association between head injury (HI) and the subsequent development of Alzheimer's disease (AD). Certain hallmarks of AD, e.g. amyloid-β (Aβ) containing deposits, may be found in patients following traumatic BI (TBI). Recent studies uncover the cellular prion protein, PrP(C), as a receptor for soluble polymeric forms of Aβ (sAβ) which are an intermediate of such deposits. We aimed to test the hypothesis that targeting of PrP(C) can prevent Aβ related spatial memory deficits in olfactory bulbectomized (OBX) mice utilized here to resemble some clinical features of AD, such as increased level of Aβ, memory loss and deficit of the CNS cholin- and serotonin-ergic systems. We demonstrated that immunization with the a.a. 95-123 fragment of cellular prion (PrP-I) recovered cortical and hippocampus neurons from OBX induced degeneration, rescued spatial memory loss in Morris water maze test and significantly decrease the Aβ level in brain tissue of these animals. Affinity purified anti-PrP-I antibodies rescued pre-synaptic biomarker synaptophysin eliciting similar effect on memory of OBX mice, and protected hippocampal neurones from Aβ25-35-induced toxicity in vitro. Immunization OBX mice with a.a. 200-213 fragment of cellular prion (PrP-II) did not reach a significance in memory protection albeit having similar to PrP-I immunization impact on Aβ level in brain tissue. The observed positive effect of targeting the PrP-I by either active or passive immunization on memory of OBX mice revealed the involvement of the PrP(C) in AD-like pathology induced by olfactory bulbectomy. This OBX model may be a useful tool for mechanistic and preclinical therapeutic investigations into the association between PrP(C) and AD.
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Affiliation(s)
- N V Bobkova
- Institute of Cell Biophysics, Russian Academy of Sciences, ul. Institutskaya, 3. Pushchino, Russia.
| | - N I Medvinskaya
- Institute of Cell Biophysics, Russian Academy of Sciences, ul. Institutskaya, 3. Pushchino, Russia.
| | - A V Kamynina
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya, 16/10, 117997 Moscow, Russia.
| | - I Y Aleksandrova
- Institute of Cell Biophysics, Russian Academy of Sciences, ul. Institutskaya, 3. Pushchino, Russia.
| | - I V Nesterova
- Institute of Cell Biophysics, Russian Academy of Sciences, ul. Institutskaya, 3. Pushchino, Russia.
| | - A N Samokhin
- Institute of Cell Biophysics, Russian Academy of Sciences, ul. Institutskaya, 3. Pushchino, Russia.
| | - D O Koroev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya, 16/10, 117997 Moscow, Russia.
| | - M P Filatova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya, 16/10, 117997 Moscow, Russia.
| | - P V Nekrasov
- Institute of Cell Biophysics, Russian Academy of Sciences, ul. Institutskaya, 3. Pushchino, Russia.
| | - A Y Abramov
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, WC1N 3BG London, UK.
| | - S V Leonov
- Institute of Cell Biophysics, Russian Academy of Sciences, ul. Institutskaya, 3. Pushchino, Russia; Department of Biology, Chemical Diversity Research Institute (CDRI), Rabochaya St., 2-A, 141400 Khimki, Moscow Region, Russia; BioBusiness Incubator, Moscow Institute of Physics and Technology, Institutsky pereulok, 9, Dolgoprudny, Moscow Region 141700, Russia.
| | - O M Volpina
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya, 16/10, 117997 Moscow, Russia.
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22
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Llorens F, Ferrer I, del Río JA. Gene expression resulting from PrPC ablation and PrPC overexpression in murine and cellular models. Mol Neurobiol 2013; 49:413-23. [PMID: 23949728 DOI: 10.1007/s12035-013-8529-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Accepted: 08/05/2013] [Indexed: 02/07/2023]
Abstract
The cellular prion protein (PrP(C)) plays a key role in prion diseases when it converts to the pathogenic form scrapie prion protein. Increasing knowledge of its participation in prion infection contrasts with the elusive and controversial data regarding its physiological role probably related to its pleiotropy, cell-specific functions, and cellular-specific milieu. Multiple approaches have been made to the increasing understanding of the molecular mechanisms and cellular functions modulated by PrP(C) at the transcriptomic and proteomic levels. Gene expression analyses have been made in several mouse and cellular models with regulated expression of PrP(C) resulting in PrP(C) ablation or PrP(C) overexpression. These analyses support previous functional data and have yielded clues about new potential functions. However, experiments on animal models have shown moderate and varied results which are difficult to interpret. Moreover, studies in cell cultures correlate little with in vivo counterparts. Yet, both animal and cell models have provided some insights on how to proceed in the future by using more refined methods and selected functional experiments.
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Affiliation(s)
- Franc Llorens
- Institute of Neuropathology, University Hospital Bellvitge-Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat, Spain,
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23
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Altered behavioral aspects of aged mice lacking the cellular prion protein. Physiol Behav 2013; 119:86-91. [DOI: 10.1016/j.physbeh.2013.06.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Revised: 03/27/2013] [Accepted: 06/05/2013] [Indexed: 11/22/2022]
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Lucena GMRS, Matheus FC, Ferreira VM, Tessele PB, Azevedo MS, Cechinel-Filho V, Prediger RD. Effects of Ethanolic Extract and Naphthoquinones Obtained from the Bulbs ofCipura paludosaon Short-Term and Long-Term Memory: Involvement of Adenosine A1and A2AReceptors. Basic Clin Pharmacol Toxicol 2012; 112:229-35. [DOI: 10.1111/bcpt.12022] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Accepted: 09/26/2012] [Indexed: 11/27/2022]
Affiliation(s)
| | - Filipe C. Matheus
- Departamento de Farmacologia, Centro de Ciências Biológicas; Universidade Federal de Santa Catarina (UFSC); Florianópolis; SC; Brazil
| | - Vania M. Ferreira
- Faculdade de Ciências da Saúde; Universidade de Brasília (UnB); Brasília; DF; Brazil
| | - Priscila B. Tessele
- Núcleo de Investigações Químico-Farmacêuticas (NIQFAR); Curso de Farmácia-CCS, Universidade do Vale do Itajaí (UNIVALI); Itajaí; SC; Brazil
| | - Mariangela S. Azevedo
- Departamento de Química, Laboratórios de Fitoquímica; Produtos Naturais e Meio Ambiente, Universidade Federal de Rondônia (Labfito-UNIR); Porto Velho; RO; Brazil
| | - Valdir Cechinel-Filho
- Núcleo de Investigações Químico-Farmacêuticas (NIQFAR); Curso de Farmácia-CCS, Universidade do Vale do Itajaí (UNIVALI); Itajaí; SC; Brazil
| | - Rui D. Prediger
- Departamento de Farmacologia, Centro de Ciências Biológicas; Universidade Federal de Santa Catarina (UFSC); Florianópolis; SC; Brazil
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Millan MJ. An epigenetic framework for neurodevelopmental disorders: from pathogenesis to potential therapy. Neuropharmacology 2012; 68:2-82. [PMID: 23246909 DOI: 10.1016/j.neuropharm.2012.11.015] [Citation(s) in RCA: 150] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2012] [Revised: 11/11/2012] [Accepted: 11/22/2012] [Indexed: 12/12/2022]
Abstract
Neurodevelopmental disorders (NDDs) are characterized by aberrant and delayed early-life development of the brain, leading to deficits in language, cognition, motor behaviour and other functional domains, often accompanied by somatic symptoms. Environmental factors like perinatal infection, malnutrition and trauma can increase the risk of the heterogeneous, multifactorial and polygenic disorders, autism and schizophrenia. Conversely, discrete genetic anomalies are involved in Down, Rett and Fragile X syndromes, tuberous sclerosis and neurofibromatosis, the less familiar Phelan-McDermid, Sotos, Kleefstra, Coffin-Lowry and "ATRX" syndromes, and the disorders of imprinting, Angelman and Prader-Willi syndromes. NDDs have been termed "synaptopathies" in reference to structural and functional disturbance of synaptic plasticity, several involve abnormal Ras-Kinase signalling ("rasopathies"), and many are characterized by disrupted cerebral connectivity and an imbalance between excitatory and inhibitory transmission. However, at a different level of integration, NDDs are accompanied by aberrant "epigenetic" regulation of processes critical for normal and orderly development of the brain. Epigenetics refers to potentially-heritable (by mitosis and/or meiosis) mechanisms controlling gene expression without changes in DNA sequence. In certain NDDs, prototypical epigenetic processes of DNA methylation and covalent histone marking are impacted. Conversely, others involve anomalies in chromatin-modelling, mRNA splicing/editing, mRNA translation, ribosome biogenesis and/or the regulatory actions of small nucleolar RNAs and micro-RNAs. Since epigenetic mechanisms are modifiable, this raises the hope of novel therapy, though questions remain concerning efficacy and safety. The above issues are critically surveyed in this review, which advocates a broad-based epigenetic framework for understanding and ultimately treating a diverse assemblage of NDDs ("epigenopathies") lying at the interface of genetic, developmental and environmental processes. This article is part of the Special Issue entitled 'Neurodevelopmental Disorders'.
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Affiliation(s)
- Mark J Millan
- Unit for Research and Discovery in Neuroscience, IDR Servier, 125 chemin de ronde, 78290 Croissy sur Seine, Paris, France.
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High levels of Cellular Prion Protein improve astrocyte development. FEBS Lett 2012; 587:238-44. [DOI: 10.1016/j.febslet.2012.11.032] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Revised: 10/31/2012] [Accepted: 11/28/2012] [Indexed: 11/21/2022]
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Rial D, Piermartiri TC, Duarte FS, Tasca CI, Walz R, Prediger RD. Overexpression of cellular prion protein (PrP(C)) prevents cognitive dysfunction and apoptotic neuronal cell death induced by amyloid-β (Aβ₁₋₄₀) administration in mice. Neuroscience 2012; 215:79-89. [PMID: 22537845 DOI: 10.1016/j.neuroscience.2012.04.034] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 04/02/2012] [Accepted: 04/07/2012] [Indexed: 11/28/2022]
Abstract
The cellular prion protein (PrP(C)) is a neuronal-anchored glycoprotein that has been associated with several functions in the CNS such as synaptic plasticity, learning and memory and neuroprotection. There is great interest in understanding the role of PrP(C) in the deleterious effects induced by the central accumulation of amyloid-β (Aβ) peptides, a pathological hallmark of Alzheimer's disease, but the existent results are still controversial. Here we compared the effects of a single intracerebroventricular (i.c.v.) injection of aggregated Aβ(1-40) peptide (400pmol/mouse) on the spatial learning and memory performance as well as hippocampal cell death biomarkers in adult wild type (Prnp(+/+)), PrP(C) knockout (Prnp(0/0)) and the PrP(C) overexpressing Tg-20 mice. Tg-20 mice, which present a fivefold increase in PrP(C) expression in comparison to wild type mice, were resistant to the Aβ(1-40)-induced spatial learning and memory impairments as indicated by reduced escape latencies to find the platform and higher percentage of time spent in the correct quadrant during training and probe test sessions of the water maze task. The protection against Aβ(1-40)-induced cognitive impairments observed in Tg-20 mice was accompanied by a significant decrease in the hippocampal expression of the activated caspase-3 protein and Bax/Bcl-2 ratio as well as reduced hippocampal cell damage assessed by MTT and propidium iodide incorporation assays. These findings indicate that the overexpression of PrP(C) prevents Aβ(1-40)-induced spatial learning and memory deficits in mice and that this response is mediated, at least in part, by the modulation of programed cell death pathways.
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Affiliation(s)
- D Rial
- Departamento de Farmacologia, Universidade Federal de Santa Catarina, UFSC, Florianópolis, SC, Brazil
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Kemp J, Després O, Sellal F, Dufour A. Theory of Mind in normal ageing and neurodegenerative pathologies. Ageing Res Rev 2012; 11:199-219. [PMID: 22186031 DOI: 10.1016/j.arr.2011.12.001] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2011] [Revised: 11/24/2011] [Accepted: 12/06/2011] [Indexed: 10/14/2022]
Abstract
This paper reviews findings in three subcomponents of social cognition (i.e., Theory of Mind, facial emotion recognition, empathy) during ageing. Changes over time in social cognition were evaluated in normal ageing and in patients with various neurodegenerative pathologies, such as Alzheimer's disease, mild cognitive impairment, frontal and temporal variants of frontotemporal lobar degeneration and Parkinson's disease. Findings suggest a decline in social cognition with normal ageing, a decline that is at least partially independent of a more general cognitive or executive decline. The investigation of neurodegenerative pathologies showing specific deficits in Theory of Mind in relation to damage to specific cerebral regions led us to suggest a neural network involved in Theory of Mind processes, namely a fronto-subcortical loop linking the basal ganglia to the regions of the frontal lobes.
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Gourdain P, Ballerini C, Nicot AB, Carnaud C. Exacerbation of experimental autoimmune encephalomyelitis in prion protein (PrPc)-null mice: evidence for a critical role of the central nervous system. J Neuroinflammation 2012; 9:25. [PMID: 22281016 PMCID: PMC3305405 DOI: 10.1186/1742-2094-9-25] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Accepted: 01/26/2012] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND The cellular prion protein (PrPc) is a host-encoded glycoprotein whose transconformation into PrP scrapie (PrPSc) initiates prion diseases. The role of PrPc in health is still obscure, but many candidate functions have been attributed to the protein, both in the immune and the nervous systems. Recent data show that experimental autoimmune encephalomyelitis (EAE) is worsened in mice lacking PrPc. Disease exacerbation has been attributed to T cells that would differentiate into more aggressive effectors when deprived of PrPc. However, alternative interpretations such as reduced resistance of neurons to autoimmune insult and exacerbated gliosis leading to neuronal deficits were not considered. METHOD To better discriminate the contribution of immune cells versus neural cells, reciprocal bone marrow chimeras with differential expression of PrPc in the lymphoid or in the central nervous system (CNS) were generated. Mice were subsequently challenged with MOG35-55 peptide and clinical disease as well as histopathology were compared in both groups. Furthermore, to test directly the T cell hypothesis, we compared the encephalitogenicity of adoptively transferred PrPc-deficient versus PrPc-sufficient, anti-MOG T cells. RESULTS First, EAE exacerbation in PrPc-deficient mice was confirmed. Irradiation exacerbated EAE in all the chimeras and controls, but disease was more severe in mice with a PrPc-deleted CNS and a normal immune system than in the reciprocal construction. Moreover, there was no indication that anti-MOG responses were different in PrPc-sufficient and PrPc-deficient mice. Paradoxically, PrPc-deficient anti-MOG 2D2 T cells were less pathogenic than PrPc-expressing 2D2 T cells. CONCLUSIONS In view of the present data, it can be concluded that the origin of EAE exacerbation in PrPc-ablated mice resides in the absence of the prion protein in the CNS. Furthermore, the absence of PrPc on both neural and immune cells does not synergize for disease worsening. These conclusions highlight the critical role of PrPc in maintaining the integrity of the CNS in situations of stress, especially during a neuroinflammatory insult.
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Affiliation(s)
- Pauline Gourdain
- INSERM, UMR S 938, Centre de Recherche Hôpital Saint-Antoine, Paris, France
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Day JJ, Sweatt JD. Epigenetic treatments for cognitive impairments. Neuropsychopharmacology 2012; 37:247-60. [PMID: 21593731 PMCID: PMC3238093 DOI: 10.1038/npp.2011.85] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2011] [Revised: 04/04/2011] [Accepted: 04/07/2011] [Indexed: 12/11/2022]
Abstract
Epigenetic mechanisms integrate signals from diverse intracellular transduction cascades and in turn regulate genetic readout. Accumulating evidence has revealed that these mechanisms are critical components of ongoing physiology and function in the adult nervous system, and are essential for many cognitive processes, including learning and memory. Moreover, a number of psychiatric disorders and syndromes that involve cognitive impairments are associated with altered epigenetic function. In this review, we will examine how epigenetic mechanisms contribute to cognition, consider how changes in these mechanisms may lead to cognitive impairments in a range of disorders and discuss the potential utility of therapeutic treatments that target epigenetic machinery. Finally, we will comment on a number of caveats associated with interpreting epigenetic changes and using epigenetic treatments, and suggest future directions for research in this area that will expand our understanding of the epigenetic changes underlying cognitive disorders.
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Affiliation(s)
- Jeremy J Day
- Department of Neurobiology and Evelyn F McKnight Brain Institute, University of Alabama at Birmingham, Birmingham, AL 35294-2182, USA.
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Schwarzbold ML, Rial D, De Bem T, Machado DG, Cunha MP, dos Santos AA, dos Santos DB, Figueiredo CP, Farina M, Goldfeder EM, Rodrigues ALS, Prediger RDS, Walz R. Effects of traumatic brain injury of different severities on emotional, cognitive, and oxidative stress-related parameters in mice. J Neurotrauma 2011; 27:1883-93. [PMID: 20649482 DOI: 10.1089/neu.2010.1318] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Cognitive deficits and psychiatric disorders are significant sequelae of traumatic brain injury (TBI). Animal models have been widely employed in TBI research, but few studies have addressed the effects of experimental TBI of different severities on emotional and cognitive parameters. In this study, mice were subjected to weight-drop TBI to induce mild, intermediate, or severe TBI. After neurological assessment, the mice recovered for 10 days, and were then subjected to a battery of behavioral tests, which included open-field, elevated plus-maze, forced swimming, tail suspension, and step-down inhibitory avoidance tests. Oxidative stress-related parameters (nonprotein thiols [NPSH], glutathione peroxidase [GPx], glutathione reductase [GR], and thiobarbituric acid reactive species [TBARS]) were quantified in the cortex and hippocampus at 2 and 24 h and 14 days after TBI, and histopathological analysis was performed 15 days after TBI. Mice subjected to mild TBI showed increased anxiety and depressive-like behaviors, while intermediate and severe TBI induced robust memory deficits. The severe TBI group also displayed increased locomotor activity. Intermediate and severe TBI caused extensive macroscopic and microscopic brain damage, while mild TBI typically had no histological abnormalities. Moreover, a significant increase in TBARS in the ipsilateral cortex and GPx in the ipsilateral hippocampus was observed at 24 h and 14 days, respectively, following intermediate TBI. The current experimental TBI model induced emotional and cognitive changes comparable to sequelae seen in human TBI, and it might therefore represent a useful approach to the study of mechanisms of and new treatments for TBI and related disorders.
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Affiliation(s)
- Marcelo L Schwarzbold
- Centro de Neurociências Aplicadas, Hospital Universitário, Universidade Federal de Santa Catarina, Florianópolis, Brazil
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Abstract
Prion diseases in humans and animals are characterized by progressive neurodegeneration and the formation of infectious particles called prions. Both features are intimately linked to a conformational transition of the cellular prion protein (PrP(C)) into aberrantly folded conformers with neurotoxic and self-replicating activities. Interestingly, there is increasing evidence that the infectious and neurotoxic properties of PrP conformers are not necessarily coupled. Transgenic mouse models revealed that some PrP mutants interfere with neuronal function in the absence of infectious prions. Vice versa, propagation of prions can occur without causing neurotoxicity. Consequently, it appears plausible that two partially independent pathways exist, one pathway leading to the propagation of infectious prions and another one that mediates neurotoxic signaling. In this review we will summarize current knowledge of neurotoxic PrP conformers and discuss the role of PrP(C) as a mediator of both stress-protective and neurotoxic signaling cascades.
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