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Raghuraman R, Aoun A, Herman M, Shetler O, Nahmani E, Hussaini SA. Lateral Entorhinal Cortex Dysfunction in Alzheimer's disease Mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.15.589589. [PMID: 38659892 PMCID: PMC11042344 DOI: 10.1101/2024.04.15.589589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
In Alzheimer's disease (AD), the formation of amyloid beta (A β ) and neurofibrillary tangles (NFTs) leads to neuronal loss in entorhinal cortex (EC), a crucial brain region involved in memory and navigation. These pathological changes are concurrent with the onset of memory-related issues in AD patients with symptoms of forgetfulness such as misplacing items, disorientation in familiar environments etc. The lateral EC (LEC) is associated with non-spatial memory processing including object recognition. Since in LEC, neurons fire in response to objects (object cells) and at locations previously occupied by objects (trace cells), pathology in this region could lead to dysfunction in object location coding. In this paper we show that a transgenic mouse model, EC-App/Tau, which expresses both APP and tau primarily in the EC region, have deficits in LEC-specific memory tasks. Using in vivo single-unit electrophysiology recordings we show that the LEC neurons are hyperactive with low information content and high sparsity compared to the controls indicating poor firing fidelity. We finally show that object cells and trace cells fire less precisely in the EC-App/Tau mice compared to controls indicating poor encoding of objects. Overall, we show that AD pathology causes erratic firing of LEC neurons and object coding defects leading to LEC-specific memory impairment.
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Rodrigues S, Anglada-Huguet M, Hochgräfe K, Kaniyappan S, Wegmann S, Mandelkow EM. Spreading of Tau Protein Does Not Depend on Aggregation Propensity. J Mol Neurosci 2023; 73:693-712. [PMID: 37606769 PMCID: PMC10694122 DOI: 10.1007/s12031-023-02143-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 07/10/2023] [Indexed: 08/23/2023]
Abstract
The stereotypical progression of Tau pathology during Alzheimer disease has been attributed to trans-neuronal spreading of misfolded Tau proteins, followed by prion-like templated aggregation of Tau. The nature of Tau and the cellular mechanisms of Tau spreading are still under debate. We hypothesized that Tau's propensity for aggregation would correlate with its ability to spread across synapses and propagate pathology. To study the progressive propagation of Tau proteins in brain regions relevant for Alzheimer disease, we used mice expressing near-physiological levels of full-length human Tau protein carrying pro-aggregant (TauΔK280, TauΔK) or anti-aggregant (TauΔK280-PP, TauΔK-PP) mutations in the entorhinal cortex (EC). To enhance Tau expression in the EC, we performed EC injections of adeno-associated virus (AAV) particles encoding TauΔK or TauΔK-PP. The brains of injected and non-injected EC/TauΔK and EC/TauΔK-PP mice were studied by immunohistological and biochemical techniques to detect Tau propagation to dentate gyrus (DG) neurons and Tau-induced pathological changes. Pro- and anti-aggregant mice had comparable low transgene expression (~0.2 times endogenous mouse Tau). They accumulated human Tau at similar rates and only in expressing EC neurons, including their axonal projections of the perforant path and presynaptic terminals in the molecular layer of the DG. Pro-aggregant EC/TauΔK mice showed misfolded Tau and synaptic protein alterations in EC neurons, not observed in anti-aggregant EC/TauΔK-PP mice. Additional AAV-mediated expression of TauΔK or TauΔK-PP in EC/TauΔK or EC/TauΔK-PP mice, respectively, increased the human Tau expression to ~0.65 times endogenous mouse Tau, with comparable spreading of TauΔK and TauΔK-PP throughout the EC. There was a low level of transcellular propagation of Tau protein, without pathological phosphorylation or misfolding, as judged by diagnostic antibodies. Additionally, TauΔK but not TauΔK-PP expression induced hippocampal astrogliosis. Low levels of pro- or anti-aggregant full-length Tau show equivalent distributions in EC neurons, independent of their aggregation propensity. Increasing the expression via AAV induce local Tau misfolding in the EC neurons, synaptotoxicity, and astrogliosis and lead to a low level of detectable trans-neuronal spreading of Tau. This depends on its concentration in the EC, but, contrary to expectations, does not depend on Tau's aggregation propensity/misfolding and does not lead to templated misfolding in recipient neurons.
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Affiliation(s)
- Sara Rodrigues
- DZNE, German Ctr. for Neurodegenerative Diseases, Venusberg-Campus 1/99, 53127, Bonn, Germany
| | - Marta Anglada-Huguet
- DZNE, German Ctr. for Neurodegenerative Diseases, Venusberg-Campus 1/99, 53127, Bonn, Germany
| | - Katja Hochgräfe
- DZNE, German Ctr. for Neurodegenerative Diseases, Venusberg-Campus 1/99, 53127, Bonn, Germany
| | - Senthilvelrajan Kaniyappan
- DZNE, German Ctr. for Neurodegenerative Diseases, Venusberg-Campus 1/99, 53127, Bonn, Germany
- CAESAR Research Center, Ludwig-Erhard-Allee 2, 53175, Bonn, Germany
- Department of Neurodegenerative Diseases and Gerontopsychiatry, University of Bonn Medical School, Bonn, Germany
| | - Susanne Wegmann
- DZNE, German Center for Neurodegenerative Diseases, Chariteplatz 1, 10117, Berlin, Germany
| | - Eva-Maria Mandelkow
- DZNE, German Ctr. for Neurodegenerative Diseases, Venusberg-Campus 1/99, 53127, Bonn, Germany.
- CAESAR Research Center, Ludwig-Erhard-Allee 2, 53175, Bonn, Germany.
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3
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Colom-Cadena M, Davies C, Sirisi S, Lee JE, Simzer EM, Tzioras M, Querol-Vilaseca M, Sánchez-Aced É, Chang YY, Holt K, McGeachan RI, Rose J, Tulloch J, Wilkins L, Smith C, Andrian T, Belbin O, Pujals S, Horrocks MH, Lleó A, Spires-Jones TL. Synaptic oligomeric tau in Alzheimer's disease - A potential culprit in the spread of tau pathology through the brain. Neuron 2023; 111:2170-2183.e6. [PMID: 37192625 DOI: 10.1016/j.neuron.2023.04.020] [Citation(s) in RCA: 35] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 03/15/2023] [Accepted: 04/17/2023] [Indexed: 05/18/2023]
Abstract
In Alzheimer's disease, fibrillar tau pathology accumulates and spreads through the brain and synapses are lost. Evidence from mouse models indicates that tau spreads trans-synaptically from pre- to postsynapses and that oligomeric tau is synaptotoxic, but data on synaptic tau in human brain are scarce. Here we used sub-diffraction-limit microscopy to study synaptic tau accumulation in postmortem temporal and occipital cortices of human Alzheimer's and control donors. Oligomeric tau is present in pre- and postsynaptic terminals, even in areas without abundant fibrillar tau deposition. Furthermore, there is a higher proportion of oligomeric tau compared with phosphorylated or misfolded tau found at synaptic terminals. These data suggest that accumulation of oligomeric tau in synapses is an early event in pathogenesis and that tau pathology may progress through the brain via trans-synaptic spread in human disease. Thus, specifically reducing oligomeric tau at synapses may be a promising therapeutic strategy for Alzheimer's disease.
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Affiliation(s)
- Martí Colom-Cadena
- The University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK
| | - Caitlin Davies
- The University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK
| | - Sònia Sirisi
- Memory Unit, Department of Neurology, Institut d'Investigacions Biomèdiques Sant Pau - Hospital de Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain; Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Ji-Eun Lee
- EaStCHEM School of Chemistry, The University of Edinburgh, Edinburgh, UK; IRR Chemistry Hub, Institute for Regeneration and Repair, The University of Edinburgh, EH16 4 UU Edinburgh, UK
| | - Elizabeth M Simzer
- The University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK
| | - Makis Tzioras
- The University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK
| | - Marta Querol-Vilaseca
- Memory Unit, Department of Neurology, Institut d'Investigacions Biomèdiques Sant Pau - Hospital de Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain; Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Érika Sánchez-Aced
- Memory Unit, Department of Neurology, Institut d'Investigacions Biomèdiques Sant Pau - Hospital de Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain; Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Ya Yin Chang
- The University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK
| | - Kristjan Holt
- The University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK
| | - Robert I McGeachan
- The University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK
| | - Jamie Rose
- The University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK
| | - Jane Tulloch
- The University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK
| | - Lewis Wilkins
- The University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK
| | - Colin Smith
- Centre for Clinical Brain Sciences and Sudden Death Brain Bank, The University of Edinburgh, Edinburgh, UK
| | - Teodora Andrian
- Nanoscopy for Nanomedicine Lab, Institute of Bioengineering of Catalonia (IBEC Barcelona Institute of Science and Technology), Barcelona, Spain
| | - Olivia Belbin
- Memory Unit, Department of Neurology, Institut d'Investigacions Biomèdiques Sant Pau - Hospital de Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain; Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Sílvia Pujals
- Department of Biological Chemistry, Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Barcelona, Spain
| | - Mathew H Horrocks
- EaStCHEM School of Chemistry, The University of Edinburgh, Edinburgh, UK; IRR Chemistry Hub, Institute for Regeneration and Repair, The University of Edinburgh, EH16 4 UU Edinburgh, UK
| | - Alberto Lleó
- Memory Unit, Department of Neurology, Institut d'Investigacions Biomèdiques Sant Pau - Hospital de Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain; Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.
| | - Tara L Spires-Jones
- The University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK.
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Zhao R, Grunke SD, Wood CA, Perez GA, Comstock M, Li MH, Singh AK, Park KW, Jankowsky JL. Activity disruption causes degeneration of entorhinal neurons in a mouse model of Alzheimer's circuit dysfunction. eLife 2022; 11:e83813. [PMID: 36468693 PMCID: PMC9873254 DOI: 10.7554/elife.83813] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 12/03/2022] [Indexed: 12/12/2022] Open
Abstract
Neurodegenerative diseases are characterized by selective vulnerability of distinct cell populations; however, the cause for this specificity remains elusive. Here, we show that entorhinal cortex layer 2 (EC2) neurons are unusually vulnerable to prolonged neuronal inactivity compared with neighboring regions of the temporal lobe, and that reelin + stellate cells connecting EC with the hippocampus are preferentially susceptible within the EC2 population. We demonstrate that neuronal death after silencing can be elicited through multiple independent means of activity inhibition, and that preventing synaptic release, either alone or in combination with electrical shunting, is sufficient to elicit silencing-induced degeneration. Finally, we discovered that degeneration following synaptic silencing is governed by competition between active and inactive cells, which is a circuit refinement process traditionally thought to end early in postnatal life. Our data suggests that the developmental window for wholesale circuit plasticity may extend into adulthood for specific brain regions. We speculate that this sustained potential for remodeling by entorhinal neurons may support lifelong memory but renders them vulnerable to prolonged activity changes in disease.
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Affiliation(s)
- Rong Zhao
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Stacy D Grunke
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Caleb A Wood
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Gabriella A Perez
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Melissa Comstock
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Ming-Hua Li
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Anand K Singh
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Kyung-Won Park
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Joanna L Jankowsky
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
- Departments of Neurology, Neurosurgery, and Molecular and Cellular Biology, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
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5
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Congdon EE, Jiang Y, Sigurdsson EM. Targeting tau only extracellularly is likely to be less efficacious than targeting it both intra- and extracellularly. Semin Cell Dev Biol 2022; 126:125-137. [PMID: 34896021 PMCID: PMC9680670 DOI: 10.1016/j.semcdb.2021.12.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 12/01/2021] [Accepted: 12/01/2021] [Indexed: 12/11/2022]
Abstract
Aggregation of the tau protein is thought to be responsible for the neurodegeneration and subsequent functional impairments in diseases that are collectively named tauopathies. Alzheimer's disease is the most common tauopathy, but the group consists of over 20 different diseases, many of which have tau pathology as their primary feature. The development of tau therapies has mainly focused on preventing the formation of and/or clearing these aggregates. Of these, immunotherapies that aim to either elicit endogenous tau antibodies or deliver exogenous ones are the most common approach in clinical trials. While their mechanism of action can involve several pathways, both extra- and intracellular, pharmaceutical companies have primarily focused on antibody-mediated clearance of extracellular tau. As we have pointed out over the years, this is rather surprising because it is well known that most of pathological tau protein is found intracellularly. It has been repeatedly shown by several groups over the past decades that antibodies can enter neurons and that their cellular uptake can be enhanced by various means, particularly by altering their charge. Here, we will briefly describe the potential extra- and intracellular mechanisms involved in antibody-mediated clearance of tau pathology, discuss these in the context of recent failures of some of the tau antibody trials, and finally provide a brief overview of how the intracellular efficacy of tau antibodies can potentially be further improved by certain modifications that aim to enhance tau clearance via specific intracellular degradation pathways.
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Affiliation(s)
- Erin E Congdon
- Department of Neuroscience and Physiology, Neuroscience Institute, New York University Grossman School of Medicine, New York, NY 10016, United States.
| | - Yixiang Jiang
- Department of Neuroscience and Physiology, Neuroscience Institute, New York University Grossman School of Medicine, New York, NY 10016, United States
| | - Einar M Sigurdsson
- Department of Neuroscience and Physiology, Neuroscience Institute, New York University Grossman School of Medicine, New York, NY 10016, United States; Department of Psychiatry, New York University Grossman School of Medicine, New York, NY 10016, United States.
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6
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Hu W, Liu F, Gong CX, Iqbal K. Does proteopathic tau propagate trans-synaptically in the brain? Mol Neurodegener 2022; 17:21. [PMID: 35296344 PMCID: PMC8925219 DOI: 10.1186/s13024-022-00527-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 03/02/2022] [Indexed: 11/10/2022] Open
Affiliation(s)
- Wen Hu
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, USA.
| | - Fei Liu
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, USA
| | - Cheng-Xin Gong
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, USA
| | - Khalid Iqbal
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, USA
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7
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Stefanovski L, Meier JM, Pai RK, Triebkorn P, Lett T, Martin L, Bülau K, Hofmann-Apitius M, Solodkin A, McIntosh AR, Ritter P. Bridging Scales in Alzheimer's Disease: Biological Framework for Brain Simulation With The Virtual Brain. Front Neuroinform 2021; 15:630172. [PMID: 33867964 PMCID: PMC8047422 DOI: 10.3389/fninf.2021.630172] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 03/08/2021] [Indexed: 12/18/2022] Open
Abstract
Despite the acceleration of knowledge and data accumulation in neuroscience over the last years, the highly prevalent neurodegenerative disease of AD remains a growing problem. Alzheimer's Disease (AD) is the most common cause of dementia and represents the most prevalent neurodegenerative disease. For AD, disease-modifying treatments are presently lacking, and the understanding of disease mechanisms continues to be incomplete. In the present review, we discuss candidate contributing factors leading to AD, and evaluate novel computational brain simulation methods to further disentangle their potential roles. We first present an overview of existing computational models for AD that aim to provide a mechanistic understanding of the disease. Next, we outline the potential to link molecular aspects of neurodegeneration in AD with large-scale brain network modeling using The Virtual Brain (www.thevirtualbrain.org), an open-source, multiscale, whole-brain simulation neuroinformatics platform. Finally, we discuss how this methodological approach may contribute to the understanding, improved diagnostics, and treatment optimization of AD.
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Affiliation(s)
- Leon Stefanovski
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Neurology with Experimental Neurology, Brain Simulation Section, Berlin, Germany
| | - Jil Mona Meier
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Neurology with Experimental Neurology, Brain Simulation Section, Berlin, Germany
| | - Roopa Kalsank Pai
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Neurology with Experimental Neurology, Brain Simulation Section, Berlin, Germany
- Bernstein Center for Computational Neuroscience Berlin, Berlin, Germany
| | - Paul Triebkorn
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Neurology with Experimental Neurology, Brain Simulation Section, Berlin, Germany
- Institut de Neurosciences des Systèmes, Aix Marseille Université, Marseille, France
| | - Tristram Lett
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Neurology with Experimental Neurology, Brain Simulation Section, Berlin, Germany
| | - Leon Martin
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Neurology with Experimental Neurology, Brain Simulation Section, Berlin, Germany
| | - Konstantin Bülau
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Neurology with Experimental Neurology, Brain Simulation Section, Berlin, Germany
| | - Martin Hofmann-Apitius
- Fraunhofer Institute for Algorithms and Scientific Computing SCAI, Sankt Augustin, Germany
| | - Ana Solodkin
- Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, TX, United States
| | | | - Petra Ritter
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Neurology with Experimental Neurology, Brain Simulation Section, Berlin, Germany
- Bernstein Center for Computational Neuroscience Berlin, Berlin, Germany
- Einstein Center for Neuroscience Berlin, Berlin, Germany
- Einstein Center Digital Future, Berlin, Germany
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8
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Abstract
Most neurodegenerative diseases are characterized by the intracellular or extracellular aggregation of misfolded proteins such as amyloid-β and tau in Alzheimer disease, α-synuclein in Parkinson disease, and TAR DNA-binding protein 43 in amyotrophic lateral sclerosis. Accumulating evidence from both human studies and disease models indicates that intercellular transmission and the subsequent templated amplification of these misfolded proteins are involved in the onset and progression of various neurodegenerative diseases. The misfolded proteins that are transferred between cells are referred to as 'pathological seeds'. Recent studies have made exciting progress in identifying the characteristics of different pathological seeds, particularly those isolated from diseased brains. Advances have also been made in our understanding of the molecular mechanisms that regulate the transmission process, and the influence of the host cell on the conformation and properties of pathological seeds. The aim of this Review is to summarize our current knowledge of the cell-to-cell transmission of pathological proteins and to identify key questions for future investigation.
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9
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From the prion-like propagation hypothesis to therapeutic strategies of anti-tau immunotherapy. Acta Neuropathol 2020; 139:3-25. [PMID: 31686182 PMCID: PMC6942016 DOI: 10.1007/s00401-019-02087-9] [Citation(s) in RCA: 105] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 10/18/2019] [Accepted: 10/19/2019] [Indexed: 12/15/2022]
Abstract
The term “propagon” is used to define proteins that may transmit misfolding in vitro, in tissues or in organisms. Among propagons, misfolded tau is thought to be involved in the pathogenic mechanisms of various “tauopathies” that include Alzheimer's disease, progressive supranuclear palsy, and argyrophilic grain disease. Here, we review the available data in the literature and point out how the prion-like tau propagation has been extended from Alzheimer's disease to tauopathies. First, in Alzheimer’s disease, the progression of tau aggregation follows stereotypical anatomical stages which may be considered as spreading. The mechanisms of the propagation are now subject to intensive and controversial research. It has been shown that tau may be secreted in the interstitial fluid in an active manner as reflected by high and constant concentration of extracellular tau during Alzheimer’s pathology. Animal and cell models have been devised to mimic tau seeding and propagation, and despite their limitations, they have further supported to the prion-like propagation hypothesis. Finally, such new ways of thinking have led to different therapeutic strategies in anti-tau immunotherapy among tauopathies and have stimulated new clinical trials. However, it appears that the prion-like propagation hypothesis mainly relies on data obtained in Alzheimer’s disease. From this review, it appears that further studies are needed (1) to characterize extracellular tau species, (2) to find the right pathological tau species to target, (3) to follow in vivo tau pathology by brain imaging and biomarkers and (4) to interpret current clinical trial results aimed at reducing the progression of these pathologies. Such inputs will be essential to have a comprehensive view of these promising therapeutic strategies in tauopathies.
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Abstract
Most common neurodegenerative diseases feature deposition of protein amyloids and degeneration of brain networks. Amyloids are ordered protein assemblies that can act as templates for their own replication through monomer addition. Evidence suggests that this characteristic may underlie the progression of pathology in neurodegenerative diseases. Many different amyloid proteins, including Aβ, tau, and α-synuclein, exhibit properties similar to those of infectious prion protein in experimental systems: discrete and self-replicating amyloid structures, transcellular propagation of aggregation, and transmissible neuropathology. This review discusses the contribution of prion phenomena and transcellular propagation to the progression of pathology in common neurodegenerative diseases such as Alzheimer's and Parkinson's. It reviews fundamental events such as cell entry, amplification, and transcellular movement. It also discusses amyloid strains, which produce distinct patterns of neuropathology and spread through the nervous system. These concepts may impact the development of new diagnostic and therapeutic strategies.
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Affiliation(s)
- Jaime Vaquer-Alicea
- Center for Alzheimer's and Neurodegenerative Diseases, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA;
| | - Marc I Diamond
- Center for Alzheimer's and Neurodegenerative Diseases, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA;
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11
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Lillehaug S, Yetman MJ, Puchades MA, Checinska MM, Kleven H, Jankowsky JL, Bjaalie JG, Leergaard TB. Brain-wide distribution of reporter expression in five transgenic tetracycline-transactivator mouse lines. Sci Data 2019; 6:190028. [PMID: 30806643 PMCID: PMC6390708 DOI: 10.1038/sdata.2019.28] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 12/19/2018] [Indexed: 11/22/2022] Open
Abstract
The spatial pattern of transgene expression in tetracycline-controlled mouse models is governed primarily by the driver line used to introduce the tetracycline-controlled transactivator (tTA). Detailed maps showing where each tTA driver activates expression are therefore essential for designing and using tet-regulated models, particularly in brain research where cell type and regional specificity determine the circuits affected by conditional gene expression. We have compiled a comprehensive online repository of serial microscopic images showing brain-wide reporter expression for five commonly used tTA driver lines. We have spatially registered all images to a common three-dimensional mouse brain anatomical reference atlas for direct comparison of spatial distribution across lines. The high-resolution images and associated metadata are shared via the web page of the EU Human Brain Project. Images can be inspected using an interactive viewing tool that includes an optional overlay feature providing anatomical delineations and reference atlas coordinates. Interactive viewing is supplemented by semi-quantitative analyses of expression levels within anatomical subregions for each tTA driver line.
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Affiliation(s)
- Sveinung Lillehaug
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Michael J. Yetman
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Maja A. Puchades
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Martyna M. Checinska
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Heidi Kleven
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Joanna L. Jankowsky
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
- Departments of Molecular and Cellular Biology, Neurology, and Neurosurgery, Huffington Center on Aging, Baylor College of Medicine, Houston, TX, USA
| | - Jan G. Bjaalie
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Trygve B. Leergaard
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
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12
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Jucker M, Walker LC. Propagation and spread of pathogenic protein assemblies in neurodegenerative diseases. Nat Neurosci 2018; 21:1341-1349. [PMID: 30258241 PMCID: PMC6375686 DOI: 10.1038/s41593-018-0238-6] [Citation(s) in RCA: 243] [Impact Index Per Article: 40.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 08/21/2018] [Indexed: 12/14/2022]
Abstract
Many neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis, are characterized by the progressive appearance of abnormal proteinaceous assemblies in the nervous system. Studies in experimental systems indicate that the assemblies originate from the prion-like seeded aggregation of specific misfolded proteins that proliferate and amass to form the intracellular and/or extracellular lesions typical of each disorder. The host in which the proteopathic seeds arise provides the biochemical and physiological environment that either supports or restricts their emergence, proliferation, self-assembly, and spread. Multiple mechanisms influence the spatiotemporal spread of seeds and the nature of the resulting lesions, one of which is the cellular uptake, release, and transport of seeds along neural pathways and networks. The characteristics of cells and regions in the affected network govern their vulnerability and thereby influence the neuropathological and clinical attributes of the disease. The propagation of pathogenic protein assemblies within the nervous system is thus determined by the interaction of the proteopathic agent and the host milieu.
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Affiliation(s)
- Mathias Jucker
- Department of Cellular Neurology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.
- German Center for Neurodegenerative Diseases (DZNE), Tübingen, Germany.
| | - Lary C Walker
- Department of Neurology and Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA.
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13
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Mughal AA, Zhang L, Fayzullin A, Server A, Li Y, Wu Y, Glass R, Meling T, Langmoen IA, Leergaard TB, Vik-Mo EO. Patterns of Invasive Growth in Malignant Gliomas-The Hippocampus Emerges as an Invasion-Spared Brain Region. Neoplasia 2018; 20:643-656. [PMID: 29793116 PMCID: PMC6030235 DOI: 10.1016/j.neo.2018.04.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2017] [Revised: 03/07/2018] [Accepted: 04/02/2018] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND: Widespread infiltration of tumor cells into surrounding brain parenchyma is a hallmark of malignant gliomas, but little data exist on the overall invasion pattern of tumor cells throughout the brain. METHODS: We have studied the invasive phenotype of malignant gliomas in two invasive mouse models and patients. Tumor invasion patterns were characterized in a patient-derived xenograft mouse model using brain-wide histological analysis and magnetic resonance (MR) imaging. Findings were histologically validated in a cdkn2a−/− PDGF-β lentivirus-induced mouse glioblastoma model. Clinical verification of the results was obtained by analysis of MR images of malignant gliomas. RESULTS: Histological analysis using human-specific cellular markers revealed invasive tumors with a non-radial invasion pattern. Tumors cells accumulated in structures located far from the transplant site, such as the optic white matter and pons, whereas certain adjacent regions were spared. As such, the hippocampus was remarkably free of infiltrating tumor cells despite the extensive invasion of surrounding regions. Similarly, MR images of xenografted mouse brains displayed tumors with bihemispheric pathology, while the hippocampi appeared relatively normal. In patients, most malignant temporal lobe gliomas were located lateral to the collateral sulcus. Despite widespread pathological fluid-attenuated inversion recovery signal in the temporal lobe, 74% of the “lateral tumors” did not show signs of involvement of the amygdalo-hippocampal complex. CONCLUSIONS: Our data provide clear evidence for a compartmental pattern of invasive growth in malignant gliomas. The observed invasion patterns suggest the presence of preferred migratory paths, as well as intra-parenchymal boundaries that may be difficult for glioma cells to traverse supporting the notion of compartmental growth. In both mice and human patients, the hippocampus appears to be a brain region that is less prone to tumor invasion.
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Affiliation(s)
- Awais A Mughal
- Vilhelm Magnus Laboratory for Neurosurgical Research, Institute for Surgical Research, Oslo University Hospital, Oslo, Norway; Department of Neurosurgery, Oslo University Hospital, and Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway; SFI-CAST-Cancer Stem Cell Innovation Center, Oslo University Hospital, Oslo, Norway.
| | - Lili Zhang
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Artem Fayzullin
- Vilhelm Magnus Laboratory for Neurosurgical Research, Institute for Surgical Research, Oslo University Hospital, Oslo, Norway; Department of Neurosurgery, Oslo University Hospital, and Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Andres Server
- Section of Neuroradiology, Department of Radiology and Nuclear Medicine, Oslo University Hospital, Oslo, Norway
| | - Yuping Li
- Neurosurgical Research, Ludwig-Maximilian University of Munich, Munich, Germany
| | - Yingxi Wu
- Neurosurgical Research, Ludwig-Maximilian University of Munich, Munich, Germany
| | - Rainer Glass
- Neurosurgical Research, Ludwig-Maximilian University of Munich, Munich, Germany
| | - Torstein Meling
- Department of Neurosurgery, Oslo University Hospital, and Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Iver A Langmoen
- Vilhelm Magnus Laboratory for Neurosurgical Research, Institute for Surgical Research, Oslo University Hospital, Oslo, Norway; Department of Neurosurgery, Oslo University Hospital, and Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway; SFI-CAST-Cancer Stem Cell Innovation Center, Oslo University Hospital, Oslo, Norway; Norwegian Center for Stem Cell Research, Department of Immunology and Transfusion Medicine, Oslo University Hospital, Norway
| | - Trygve B Leergaard
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Norway
| | - Einar O Vik-Mo
- Vilhelm Magnus Laboratory for Neurosurgical Research, Institute for Surgical Research, Oslo University Hospital, Oslo, Norway; Department of Neurosurgery, Oslo University Hospital, and Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway; SFI-CAST-Cancer Stem Cell Innovation Center, Oslo University Hospital, Oslo, Norway; Norwegian Center for Stem Cell Research, Department of Immunology and Transfusion Medicine, Oslo University Hospital, Norway
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14
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Ayers JI, Giasson BI, Borchelt DR. Prion-like Spreading in Tauopathies. Biol Psychiatry 2018; 83:337-346. [PMID: 28506438 PMCID: PMC5640465 DOI: 10.1016/j.biopsych.2017.04.003] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 03/31/2017] [Accepted: 04/04/2017] [Indexed: 10/19/2022]
Abstract
Tau is a microtubule-associated protein that functions in regulating cytoskeleton dynamics, especially in neurons. Misfolded and aggregated forms of tau produce pathological structures in a number of neurodegenerative diseases, including Alzheimer's disease (AD) and tauopathy dementias. These disorders can present with a sporadic etiology, such as in AD, or a familial etiology, such as in some cases of frontotemporal dementia with parkinsonism. Notably, the pathological features of tau pathology in these diseases can be very distinct. For example, the tau pathology in corticobasal degeneration is distinct from that of an AD patient. A wealth of evidence has emerged within the last decade to suggest that the misfolded tau in tauopathies possesses prion-like features and that such features may explain the diverse characteristics of tauopathies. The prion-like concept for tauopathies arose initially from the observation that the progressive accumulation of tau pathology as the symptoms of AD progress seemed to follow anatomically linked pathways. Subsequent studies in cell and animal models revealed that misfolded tau can propagate from cell to cell and from region to region in the brain through direct neuroanatomical connections. Studies in these cell and mouse models have demonstrated that experimentally propagated forms of misfolded tau can exist as conformationally distinct "strains" with unique biochemical, morphological, and neuropathological characteristics. This review discusses the clinical, pathological, and genetic diversity of tauopathies and the discoveries underlying the emerging view that the unique features of clinically distinct tauopathies may be a reflection of the strain of misfolded tau that propagates in each disease.
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Affiliation(s)
- Jacob I Ayers
- Department of Neuroscience, University of Florida, Gainesville, Florida; Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, Florida; McKnight Brain Institute, University of Florida, Gainesville, Florida
| | - Benoit I Giasson
- Department of Neuroscience, University of Florida, Gainesville, Florida; Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, Florida; McKnight Brain Institute, University of Florida, Gainesville, Florida
| | - David R Borchelt
- Department of Neuroscience, University of Florida, Gainesville, Florida; Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, Florida; McKnight Brain Institute, University of Florida, Gainesville, Florida.
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15
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Abstract
A pathway from the natively unfolded microtubule-associated protein Tau to a highly structured amyloid fibril underlies human Tauopathies. This ordered assembly causes disease and represents the gain of toxic function. In recent years, evidence has accumulated to suggest that Tau inclusions form first in a small number of brain cells, from where they propagate to other regions, resulting in neurodegeneration and disease. Propagation of pathology is often called prion-like, which refers to the capacity of an assembled protein to induce the same abnormal conformation in a protein of the same kind, initiating a self-amplifying cascade. In addition, prion-like encompasses the release of protein aggregates from brain cells and their uptake by neighboring cells. In mice, the intracerebral injection of Tau inclusions induces the ordered assembly of monomeric Tau, followed by its spreading to distant brain regions. Conformational differences between Tau aggregates from transgenic mouse brain and in vitro assembled recombinant protein account for the greater seeding potency of brain aggregates. Short fibrils constitute the major species of seed-competent Tau in the brains of transgenic mice. The existence of multiple human Tauopathies with distinct fibril morphologies has led to the suggestion that different molecular conformers (or strains) of aggregated Tau exist.
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Affiliation(s)
- Michel Goedert
- MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, United Kingdom;
| | - David S Eisenberg
- Department of Biological Chemistry and Howard Hughes Medical Institute, University of California, Los Angeles, California 90095
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Abstract
Senile plaques and neurofibrillary tangles are the principal histopathologic hallmarks of Alzheimer disease. The essential constituents of these lesions are structurally abnormal variants of normally generated proteins: Aβ protein in plaques and tau protein in tangles. At the molecular level, both proteins in a pathogenic state share key properties with classic prions, i.e., they consist of alternatively folded, β-sheet-rich forms of the proteins that autopropagate by the seeded corruption and self-assembly of like proteins. Other similarities with prions include the ability to manifest as polymorphic and polyfunctional strains, resistance to chemical and enzymatic destruction, and the ability to spread within the brain and from the periphery to the brain. In Alzheimer disease, current evidence indicates that the pathogenic cascade follows from the endogenous, sequential corruption of Aβ and then tau. Therapeutic options include reducing the production or multimerization of the proteins, uncoupling the Aβ-tauopathy connection, or promoting the inactivation or removal of anomalous assemblies from the brain. Although aberrant Aβ appears to be the prime mover of Alzheimer disease pathogenesis, once set in motion by Aβ, the prion-like propagation of tauopathy may proceed independently of Aβ; if so, Aβ might be solely targeted as an early preventive measure, but optimal treatment of Alzheimer disease at later stages of the cascade could require intervention in both pathways.
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Affiliation(s)
- Lary C Walker
- Department of Neurology and Yerkes National Primate Research Center, Emory University, Atlanta, GA, United States.
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17
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Trans-Synaptic Spread of Amyloid- β in Alzheimer's Disease: Paths to β-Amyloidosis. Neural Plast 2017; 2017:5281829. [PMID: 29435372 PMCID: PMC5757149 DOI: 10.1155/2017/5281829] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 11/15/2017] [Accepted: 11/27/2017] [Indexed: 01/10/2023] Open
Abstract
Neuronal activity has a strong causal role in the production and release of the neurotoxic β-amyloid peptide (Aβ). Because of this close link, gradual accumulation of Aβ into amyloid plaques has been reported in brain areas with intense neuronal activity, including cortical regions that display elevated activation at resting state. However, the link between Aβ and activity is not always linear and recent studies report exceptions to the view of “more activity, more plaques.” Here, we review the literature about the activity-dependent production of Aβ in both human cases and AD models and focus on the evidences that brain regions with elevated convergence of synaptic connections (herein referred to as brain nodes) are particularly vulnerable to Aβ accumulation. Next, we will examine data supporting the hypothesis that, since Aβ is released from synaptic terminals, β-amyloidosis can spread in AD brain by advancing through synaptically connected regions, which makes brain nodes vulnerable to Aβ accumulation. Finally, we consider possible mechanisms that account for β-amyloidosis progression through synaptically linked regions.
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18
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Mudher A, Colin M, Dujardin S, Medina M, Dewachter I, Alavi Naini SM, Mandelkow EM, Mandelkow E, Buée L, Goedert M, Brion JP. What is the evidence that tau pathology spreads through prion-like propagation? Acta Neuropathol Commun 2017; 5:99. [PMID: 29258615 PMCID: PMC5735872 DOI: 10.1186/s40478-017-0488-7] [Citation(s) in RCA: 236] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 10/30/2017] [Indexed: 12/21/2022] Open
Abstract
Emerging experimental evidence suggests that the spread of tau pathology in the brain in Tauopathies reflects the propagation of abnormal tau species along neuroanatomically connected brain areas. This propagation could occur through a "prion-like" mechanism involving transfer of abnormal tau seeds from a "donor cell" to a "recipient cell" and recruitment of normal tau in the latter to generate new tau seeds. This review critically appraises the evidence that the spread of tau pathology occurs via such a "prion-like" mechanism and proposes a number of recommendations for directing future research. Recommendations for definitions of frequently used terms in the tau field are presented in an attempt to clarify and standardize interpretation of research findings. Molecular and cellular factors affecting tau aggregation are briefly reviewed, as are potential contributions of physiological and pathological post-translational modifications of tau. Additionally, the experimental evidence for tau seeding and "prion-like" propagation of tau aggregation that has emerged from cellular assays and in vivo models is discussed. Propagation of tau pathology using "prion-like" mechanisms is expected to incorporate several steps including cellular uptake, templated seeding, secretion and intercellular transfer through synaptic and non-synaptic pathways. The experimental findings supporting each of these steps are reviewed. The clinical validity of these experimental findings is then debated by considering the supportive or contradictory findings from patient samples. Further, the role of physiological tau release in this scenario is examined because emerging data shows that tau is secreted but the physiological function (if any) of this secretion in the context of propagation of pathological tau seeds is unclear. Bona fide prions exhibit specific properties, including transmission from cell to cell, tissue to tissue and organism to organism. The propagation of tau pathology has so far not been shown to exhibit all of these steps and how this influences the debate of whether or not abnormal tau species can propagate in a "prion-like" manner is discussed. The exact nature of tau seeds responsible for propagation of tau pathology in human tauopathies remains controversial; it might be tightly linked to the existence of tau strains stably propagating peculiar patterns of neuropathological lesions, corresponding to the different patterns seen in human tauopathies. That this is a property shared by all seed-competent tau conformers is not yet firmly established. Further investigation is also required to clarify the relationship between propagation of tau aggregates and tau-induced toxicity. Genetic variants identified as risks factors for tauopathies might play a role in propagation of tau pathology, but many more studies are needed to document this. The contribution of selective vulnerability of neuronal populations, as an alternative to prion-like mechanisms to explain spreading of tau pathology needs to be clarified. Learning from the prion field will be helpful to enhance our understanding of propagation of tau pathology. Finally, development of better models is expected to answer some of these key questions and allow for the testing of propagation-centred therapies.
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Affiliation(s)
- Amrit Mudher
- University of Southampton, Biological Sciences, Faculty of Natural and Environmental Sciences, SO17 1BJ, Southampton, UK.
| | - Morvane Colin
- Univ. Lille, Inserm, CHU-Lille, UMR-S 1172, LabEx DISTALZ, 59000, Lille, France
| | - Simon Dujardin
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Miguel Medina
- Network Center for Biomedical Research in Neurodegenerative Diseases (CIBERNED), Madrid, Spain; CIEN Foundation, Queen Sofia Foundation Alzheimer Center, Madrid, Spain
| | - Ilse Dewachter
- Dementia Research Group, BioMedical Research Institute, Hasselt University, 3500, Hasselt, Belgium
| | - Seyedeh Maryam Alavi Naini
- Institut de Biologie Paris Seine-Laboratoire Neuroscience Paris Seine INSERM UMRS 1130, CNRS UMR 8246, UPMC UM 118 Université Pierre et Marie Curie, Paris, France
| | - Eva-Maria Mandelkow
- DZNE (German Ctr. Neurodegen. Diseases), Bonn, Germany
- CAESAR Research Center, Bonn, Germany
- DESY, Hamburg, Germany
| | - Eckhard Mandelkow
- DZNE (German Ctr. Neurodegen. Diseases), Bonn, Germany
- CAESAR Research Center, Bonn, Germany
- DESY, Hamburg, Germany
| | - Luc Buée
- Univ. Lille, Inserm, CHU-Lille, UMR-S 1172, LabEx DISTALZ, 59000, Lille, France
| | - Michel Goedert
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, CB2 0QH, Cambridge, UK
| | - Jean-Pierre Brion
- Laboratory of Histology, Neuroanatomy and Neuropathology Université Libre de Bruxelles, Faculty of Medicine, ULB Neuroscience Institute (UNI) 808, route de Lennik 1070, Brussels, Belgium.
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Kanter BR, Lykken CM, Avesar D, Weible A, Dickinson J, Dunn B, Borgesius NZ, Roudi Y, Kentros CG. A Novel Mechanism for the Grid-to-Place Cell Transformation Revealed by Transgenic Depolarization of Medial Entorhinal Cortex Layer II. Neuron 2017; 93:1480-1492.e6. [PMID: 28334610 DOI: 10.1016/j.neuron.2017.03.001] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 12/30/2016] [Accepted: 02/28/2017] [Indexed: 01/13/2023]
Abstract
The spatial receptive fields of neurons in medial entorhinal cortex layer II (MECII) and in the hippocampus suggest general and environment-specific maps of space, respectively. However, the relationship between these receptive fields remains unclear. We reversibly manipulated the activity of MECII neurons via chemogenetic receptors and compared the changes in downstream hippocampal place cells to those of neurons in MEC. Depolarization of MECII impaired spatial memory and elicited drastic changes in CA1 place cells in a familiar environment, similar to those seen during remapping between distinct environments, while hyperpolarization did not. In contrast, both manipulations altered the firing rate of MEC neurons without changing their firing locations. Interestingly, only depolarization caused significant changes in the relative firing rates of individual grid fields, reconfiguring the spatial input from MEC. This suggests a novel mechanism of hippocampal remapping whereby rate changes in MEC neurons lead to locational changes of hippocampal place fields.
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Affiliation(s)
- Benjamin R Kanter
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Norwegian University of Science and Technology, Olav Kyrres gate 9, 7030 Trondheim, Norway; Institute of Neuroscience, University of Oregon, 1254 University of Oregon, Eugene, OR 97403, USA
| | - Christine M Lykken
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Norwegian University of Science and Technology, Olav Kyrres gate 9, 7030 Trondheim, Norway; Institute of Neuroscience, University of Oregon, 1254 University of Oregon, Eugene, OR 97403, USA
| | - Daniel Avesar
- Institute of Neuroscience, University of Oregon, 1254 University of Oregon, Eugene, OR 97403, USA
| | - Aldis Weible
- Institute of Neuroscience, University of Oregon, 1254 University of Oregon, Eugene, OR 97403, USA
| | - Jasmine Dickinson
- Institute of Neuroscience, University of Oregon, 1254 University of Oregon, Eugene, OR 97403, USA
| | - Benjamin Dunn
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Norwegian University of Science and Technology, Olav Kyrres gate 9, 7030 Trondheim, Norway
| | - Nils Z Borgesius
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Norwegian University of Science and Technology, Olav Kyrres gate 9, 7030 Trondheim, Norway
| | - Yasser Roudi
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Norwegian University of Science and Technology, Olav Kyrres gate 9, 7030 Trondheim, Norway
| | - Clifford G Kentros
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Norwegian University of Science and Technology, Olav Kyrres gate 9, 7030 Trondheim, Norway; Institute of Neuroscience, University of Oregon, 1254 University of Oregon, Eugene, OR 97403, USA.
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20
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Fu H, Hussaini SA, Wegmann S, Profaci C, Daniels JD, Herman M, Emrani S, Figueroa HY, Hyman BT, Davies P, Duff KE. 3D Visualization of the Temporal and Spatial Spread of Tau Pathology Reveals Extensive Sites of Tau Accumulation Associated with Neuronal Loss and Recognition Memory Deficit in Aged Tau Transgenic Mice. PLoS One 2016; 11:e0159463. [PMID: 27466814 PMCID: PMC4965059 DOI: 10.1371/journal.pone.0159463] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Accepted: 07/01/2016] [Indexed: 11/19/2022] Open
Abstract
3D volume imaging using iDISCO+ was applied to observe the spatial and temporal progression of tau pathology in deep structures of the brain of a mouse model that recapitulates the earliest stages of Alzheimer’s disease (AD). Tau pathology was compared at four timepoints, up to 34 months as it spread through the hippocampal formation and out into the neocortex along an anatomically connected route. Tau pathology was associated with significant gliosis. No evidence for uptake and accumulation of tau by glia was observed. Neuronal cells did appear to have internalized tau, including in extrahippocampal areas as a small proportion of cells that had accumulated human tau protein did not express detectible levels of human tau mRNA. At the oldest timepoint, mature tau pathology in the entorhinal cortex (EC) was associated with significant cell loss. As in human AD, mature tau pathology in the EC and the presence of tau pathology in the neocortex correlated with cognitive impairment. 3D volume imaging is an ideal technique to easily monitor the spread of pathology over time in models of disease progression.
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Affiliation(s)
- Hongjun Fu
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, New York, United States of America
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York, United States of America
| | - S. Abid Hussaini
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, New York, United States of America
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York, United States of America
| | - Susanne Wegmann
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, United States of America
| | - Caterina Profaci
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, New York, United States of America
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York, United States of America
| | - Jacob D. Daniels
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, New York, United States of America
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York, United States of America
| | - Mathieu Herman
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, New York, United States of America
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York, United States of America
| | - Sheina Emrani
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, New York, United States of America
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York, United States of America
| | - Helen Y. Figueroa
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, New York, United States of America
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York, United States of America
| | - Bradley T. Hyman
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, United States of America
| | - Peter Davies
- Litwin-Zucker Center for Research in Alzheimer's Disease, Feinstein Institute for Medical Research, North Shore/LIJ Health System, Manhasset, New York, United States of America
| | - Karen E. Duff
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, New York, United States of America
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York, United States of America
- * E-mail:
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21
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Walsh DM, Selkoe DJ. A critical appraisal of the pathogenic protein spread hypothesis of neurodegeneration. Nat Rev Neurosci 2016; 17:251-60. [PMID: 26988744 DOI: 10.1038/nrn.2016.13] [Citation(s) in RCA: 207] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
There has been an explosion in the number of papers discussing the hypothesis of 'pathogenic spread' in neurodegenerative disease - the idea that abnormal forms of disease-associated proteins, such as tau or α-synuclein, physically move from neuron to neuron to induce disease progression. However, whether inter-neuronal spread of protein aggregates actually occurs in humans and, if so, whether it causes symptom onset remain uncertain. Even if pathogenic spread is proven in humans, it is unclear how much this would alter the specific therapeutic approaches that are in development. A critical appraisal of this increasingly popular hypothesis thus seems both important and timely.
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Affiliation(s)
- Dominic M Walsh
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Dennis J Selkoe
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
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22
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Zhao R, Grunke SD, Keralapurath MM, Yetman MJ, Lam A, Lee TC, Sousounis K, Jiang Y, Swing DA, Tessarollo L, Ji D, Jankowsky JL. Impaired Recall of Positional Memory following Chemogenetic Disruption of Place Field Stability. Cell Rep 2016; 16:793-804. [PMID: 27373150 PMCID: PMC4956499 DOI: 10.1016/j.celrep.2016.06.032] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 03/03/2016] [Accepted: 06/03/2016] [Indexed: 11/06/2022] Open
Abstract
The neural network of the temporal lobe is thought to provide a cognitive map of our surroundings. Functional analysis of this network has been hampered by coarse tools that often result in collateral damage to other circuits. We developed a chemogenetic system to temporally control electrical input into the hippocampus. When entorhinal input to the perforant path was acutely silenced, hippocampal firing patterns became destabilized and underwent extensive remapping. We also found that spatial memory acquired prior to neural silencing was impaired by loss of input through the perforant path. Together, our experiments show that manipulation of entorhinal activity destabilizes spatial coding and disrupts spatial memory. Moreover, we introduce a chemogenetic model for non-invasive neuronal silencing that offers multiple advantages over existing strategies in this setting.
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Affiliation(s)
- Rong Zhao
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Stacy D Grunke
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | | | - Michael J Yetman
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Alexander Lam
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Department of Cognitive Science, Rice University, Houston, TX 77251, USA
| | - Tang-Cheng Lee
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | | | - Yongying Jiang
- Institute for Applied Cancer Science, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA
| | - Deborah A Swing
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA
| | - Lino Tessarollo
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA
| | - Daoyun Ji
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
| | - Joanna L Jankowsky
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Department of Neurology, Baylor College of Medicine, Houston, TX 77030, USA; Department of Neurosurgery, Baylor College of Medicine, Houston, TX 77030, USA; Huffington Center on Aging, Baylor College of Medicine, Houston, TX 77030, USA.
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Sanders DW, Kaufman SK, Holmes BB, Diamond MI. Prions and Protein Assemblies that Convey Biological Information in Health and Disease. Neuron 2016; 89:433-48. [PMID: 26844828 DOI: 10.1016/j.neuron.2016.01.026] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Prions derived from the prion protein (PrP) were first characterized as infectious agents that transmit pathology between individuals. However, the majority of cases of neurodegeneration caused by PrP prions occur sporadically. Proteins that self-assemble as cross-beta sheet amyloids are a defining pathological feature of infectious prion disorders and all major age-associated neurodegenerative diseases. In fact, multiple non-infectious proteins exhibit properties of template-driven self-assembly that are strikingly similar to PrP. Evidence suggests that like PrP, many proteins form aggregates that propagate between cells and convert cognate monomer into ordered assemblies. We now recognize that numerous proteins assemble into macromolecular complexes as part of normal physiology, some of which are self-amplifying. This review highlights similarities among infectious and non-infectious neurodegenerative diseases associated with prions, emphasizing the normal and pathogenic roles of higher-order protein assemblies. We propose that studies of the structural and cellular biology of pathological versus physiological aggregates will be mutually informative.
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Affiliation(s)
- David W Sanders
- Center for Alzheimer's and Neurodegenerative Diseases, UT Southwestern Medical Center, Dallas, TX 75390, USA; Program in Neuroscience, Washington University School of Medicine in St. Louis, St. Louis, MO 63130, USA
| | - Sarah K Kaufman
- Center for Alzheimer's and Neurodegenerative Diseases, UT Southwestern Medical Center, Dallas, TX 75390, USA; Program in Neuroscience, Washington University School of Medicine in St. Louis, St. Louis, MO 63130, USA
| | - Brandon B Holmes
- Center for Alzheimer's and Neurodegenerative Diseases, UT Southwestern Medical Center, Dallas, TX 75390, USA; Program in Neuroscience, Washington University School of Medicine in St. Louis, St. Louis, MO 63130, USA
| | - Marc I Diamond
- Center for Alzheimer's and Neurodegenerative Diseases, UT Southwestern Medical Center, Dallas, TX 75390, USA.
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Yetman MJ, Fowler SW, Jankowsky JL. Humanized Tau Mice with Regionalized Amyloid Exhibit Behavioral Deficits but No Pathological Interaction. PLoS One 2016; 11:e0153724. [PMID: 27070146 PMCID: PMC4829202 DOI: 10.1371/journal.pone.0153724] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Accepted: 04/01/2016] [Indexed: 12/14/2022] Open
Abstract
Alzheimer’s disease (AD) researchers have struggled for decades to draw a causal link between extracellular Aβ aggregation and intraneuronal accumulation of microtubule-associated protein tau. The amyloid cascade hypothesis posits that Aβ deposition promotes tau hyperphosphorylation, tangle formation, cell loss, vascular damage, and dementia. While the genetics of familial AD and the pathological staging of sporadic disease support this sequence of events, attempts to examine the molecular mechanism in transgenic animal models have largely relied on models of other inherited tauopathies as the basis for testing the interaction with Aβ. In an effort to more accurately model the relationship between Aβ and wild-type tau in AD, we intercrossed mice that overproduce human Aβ with a tau substitution model in which all 6 isoforms of the human protein are expressed in animals lacking murine tau. We selected an amyloid model in which pathology was biased towards the entorhinal region so that we could further examine whether the anticipated changes in tau phosphorylation occurred at the site of Aβ deposition or in synaptically connected regions. We found that Aβ and tau had independent effects on locomotion, learning, and memory, but found no behavioral evidence for an interaction between the two transgenes. Moreover, we saw no indication of amyloid-induced changes in the phosphorylation or aggregation of human tau either within the entorhinal area or elsewhere. These findings suggest that robust amyloid pathology within the medial temporal lobe has little effect on the metabolism of wild type human tau in this model.
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Affiliation(s)
- Michael J. Yetman
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, United States of America
| | - Stephanie W. Fowler
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, United States of America
| | - Joanna L. Jankowsky
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Neurology, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Neurosurgery, Baylor College of Medicine, Houston, Texas, United States of America
- * E-mail:
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Baker S, Götz J. A local insult of okadaic acid in wild-type mice induces tau phosphorylation and protein aggregation in anatomically distinct brain regions. Acta Neuropathol Commun 2016; 4:32. [PMID: 27037086 PMCID: PMC4818468 DOI: 10.1186/s40478-016-0300-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 03/15/2016] [Indexed: 12/21/2022] Open
Abstract
In Alzheimer’s disease (AD), the distribution and density of neurofibrillary tangles, a histological hallmark comprised predominately of phosphorylated tau protein, follows a distinct pattern through anatomically connected brain regions. Studies in transgenic mice engineered to regionally confine tau expression have suggested spreading of tau within neural networks. Furthermore, injection of protein lysates isolated from brains of transgenic mice or patients with tauopathies, including AD, were shown to behave like seeds, accelerating tau pathology and tangle formation in predisposed mice. However, it remains unclear how the initiation of primary aggregation events occurs and what triggers further dissemination throughout the neural system. To consolidate these findings, we pursued an alternative approach to assess the spreading of endogenous phosphorylated tau. To generate endogenous seeds, 130 nl of 100 μM protein phosphatase 2A inhibitor okadaic acid (OA) was injected unilaterally into the amygdala of 8-month-old C57Bl/6 wild-type mice. OA was detected in brain tissue by ELISA, and found to be restricted to the injected hemispheric quadrant, where it remained detectable a week post-injection. OA injection induced tau phosphorylation that was observed not only at the injection site but also in anatomically distinct areas across both hemispheres, including the cortex and hippocampus 24 h post-injection. An increase in insoluble tau was also observed in both hemispheres of injected brains by 7 days. Furthermore, thioflavin-S detected protein aggregation at the injection site and in the cortex of both injected and contralateral hemispheres. OA injection induced no thioflavin-positivity in tau knock-out mice. The data demonstrates that a local OA insult can rapidly initiate changes in protein phosphorylation, solubility and aggregation at anatomically distant sites. This model suggests that tau phosphorylation can be both a primary response to an insult, and a secondary response communicated to non-exposed brains regions. The study highlights the use of OA to assist in understanding the initiation of tau spreading in vivo.
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Propagation of tau pathology: hypotheses, discoveries, and yet unresolved questions from experimental and human brain studies. Acta Neuropathol 2016; 131:27-48. [PMID: 26576562 DOI: 10.1007/s00401-015-1507-z] [Citation(s) in RCA: 124] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 11/04/2015] [Accepted: 11/05/2015] [Indexed: 12/22/2022]
Abstract
Tau is a microtubule-associated protein and a key regulator of microtubule stabilization as well as the main component of neurofibrillary tangles-a principle neuropathological hallmark of Alzheimer's disease (AD)-as well as pleomorphic neuronal and glial inclusions in neurodegenerative tauopathies. Cross-sectional studies of neurofibrillary pathology in AD reveal a stereotypic spatiotemporal pattern of neuronal vulnerability that correlates with disease severity; however, the relationship of this pattern to disease progression is less certain and exceptions to the typical pattern have been described in a subset of AD patients. The basis for the selective vulnerability of specific populations of neurons to tau pathology and cell death is largely unknown, although there have been a number of hypotheses based upon shared properties of vulnerable neurons (e.g., degree of axonal myelination or synaptic plasticity). A recent hypothesis for selective vulnerability takes into account the emerging science of functional connectivity based upon resting state functional magnetic resonance imaging, where subsets of neurons that fire synchronously define patterns of degeneration similar to specific neurodegenerative disorders, including various tauopathies. In the past 6 years, the concept of tau propagation has emerged from numerous studies in cell and animal models suggesting that tau moves from cell-to-cell and that this may trigger aggregation and region-to-region spread of tau pathology within the brain. How the spread of tau pathology relates to functional connectivity is an area of active investigation. Observations of templated folding and propagation of tau have prompted comparisons of tau to prions, the pathogenic proteins in transmissible spongiform encephalopathies. In this review, we discuss the most compelling studies in the field, discuss their shortcomings and consider their implications with respect to human tauopathies as well as the controversy that tauopathies may be prion-like disorders.
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Wegmann S, Maury EA, Kirk MJ, Saqran L, Roe A, DeVos SL, Nicholls S, Fan Z, Takeda S, Cagsal-Getkin O, William CM, Spires-Jones TL, Pitstick R, Carlson GA, Pooler AM, Hyman BT. Removing endogenous tau does not prevent tau propagation yet reduces its neurotoxicity. EMBO J 2015; 34:3028-41. [PMID: 26538322 DOI: 10.15252/embj.201592748] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2015] [Accepted: 10/02/2015] [Indexed: 12/22/2022] Open
Abstract
In Alzheimer's disease and tauopathies, tau protein aggregates into neurofibrillary tangles that progressively spread to synaptically connected brain regions. A prion-like mechanism has been suggested: misfolded tau propagating through the brain seeds neurotoxic aggregation of soluble tau in recipient neurons. We use transgenic mice and viral tau expression to test the hypotheses that trans-synaptic tau propagation, aggregation, and toxicity rely on the presence of endogenous soluble tau. Surprisingly, mice expressing human P301Ltau in the entorhinal cortex showed equivalent tau propagation and accumulation in recipient neurons even in the absence of endogenous tau. We then tested whether the lack of endogenous tau protects against misfolded tau aggregation and toxicity, a second prion model paradigm for tau, using P301Ltau-overexpressing mice with severe tangle pathology and neurodegeneration. Crossed onto tau-null background, these mice had similar tangle numbers but were protected against neurotoxicity. Therefore, misfolded tau can propagate across neural systems without requisite templated misfolding, but the absence of endogenous tau markedly blunts toxicity. These results show that tau does not strictly classify as a prion protein.
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Affiliation(s)
- Susanne Wegmann
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Eduardo A Maury
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Molly J Kirk
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Lubna Saqran
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Allyson Roe
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Sarah L DeVos
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Samantha Nicholls
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Zhanyun Fan
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Shuko Takeda
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Ozge Cagsal-Getkin
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Christopher M William
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Tara L Spires-Jones
- Centre for Cognitive and Neural Systems and Euan MacDonald Centre, University of Edinburgh, Edinburgh, UK
| | | | | | - Amy M Pooler
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Bradley T Hyman
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
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