1
|
Overeem LH, Raffaelli B, Fleischmann R, Süße M, Vogelgesang A, Maceski AM, Papadopoulou A, Ruprecht K, Su W, Koch M, Siebert A, Arkuszewski M, Tenenbaum N, Kuhle J, Reuter U. Serum tau protein elevation in migraine: a cross-sectional case-control study. J Headache Pain 2023; 24:130. [PMID: 37726712 PMCID: PMC10507851 DOI: 10.1186/s10194-023-01663-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 09/01/2023] [Indexed: 09/21/2023] Open
Abstract
BACKGROUND Migraine is a disorder associated with neuropeptide release, pain and inflammation. Tau protein has recently been linked to inflammatory diseases and can be influenced by neuropeptides such as CGRP, a key neurotransmitter in migraine. Here, we report serum concentrations of total-tau protein in migraine patients and healthy controls. METHODS In this cross-sectional study, interictal blood samples from n = 92 patients with episodic migraine (EM), n = 93 patients with chronic migraine (CM), and n = 42 healthy matched controls (HC) were studied. We assessed serum total-tau protein (t-tau) and for comparison neurofilament light chain protein (NfL), glial fibrillary acidic protein (GFAP), and ubiquitin carboxy-terminal hydrolase L (UCH-L1) concentrations using the Neurology 4-plex kit, on a single molecule array HD-X Analyzer (Quanterix Corp Lexington, MA). Matched serum/cerebrospinal fluid (CSF) samples were used for post-hoc evaluations of a central nervous system (CNS) source of relevant findings. We applied non-parametric tests to compare groups and assess correlations. RESULTS Serum t-tau concentrations were elevated in EM [0.320 (0.204 to 0.466) pg/mL] and CM [0.304 (0.158 to 0.406) pg/mL] patients compared to HC [0.200 (0.114 to 0.288) pg/mL] (p = 0.002 vs. EM; p = 0.025 vs. CM). EM with aura [0.291 (0.184 to 0.486 pg/mL); p = 0.013] and EM without aura [0.332 (0.234 to 0.449) pg/mL; p = 0.008] patients had higher t-tau levels than HC but did not differ between each other. Subgroup analysis of CM with/without preventive treatment revealed elevated t-tau levels compared to HC only in the non-prevention group [0.322 (0.181 to 0.463) pg/mL; p = 0.009]. T-tau was elevated in serum (p = 0.028) but not in cerebrospinal fluid (p = 0.760). In contrast to t-tau, all proteins associated with cell damage (NfL, GFAP, and UCH-L1), did not differ between groups. DISCUSSION Migraine is associated with t-tau elevation in serum but not in the CSF. Our clinical study identifies t-tau as a new target for migraine research.
Collapse
Affiliation(s)
- Lucas Hendrik Overeem
- Department of Neurology With Experimental Neurology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, Berlin, 10117, Germany
- Doctoral Program, International Graduate Program Medical Neurosciences, Humboldt Graduate School, Berlin, 10117, Germany
| | - Bianca Raffaelli
- Department of Neurology With Experimental Neurology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, Berlin, 10117, Germany
- Clinician Scientist Program, Berlin Institute of Health (BIH), Berlin, 10117, Germany
| | - Robert Fleischmann
- Department of Neurology, Universitätsmedizin Greifswald, Greifswald, 17475, Germany
| | - Marie Süße
- Department of Neurology, Universitätsmedizin Greifswald, Greifswald, 17475, Germany
| | - Antje Vogelgesang
- Department of Neurology, Universitätsmedizin Greifswald, Greifswald, 17475, Germany
| | - Aleksandra Maleska Maceski
- Department of Neurology, University Hospital and University of Basel, Basel, 4051, Switzerland
- Multiple Sclerosis Centre and Research Center for Clinical Neuroimmunology and Neuroscience (RC2NB), Departments of Biomedicine and Clinical Research, University Hospital and University of Basel, Basel, 4051, Switzerland
| | - Athina Papadopoulou
- Department of Neurology, University Hospital and University of Basel, Basel, 4051, Switzerland
- Multiple Sclerosis Centre and Research Center for Clinical Neuroimmunology and Neuroscience (RC2NB), Departments of Biomedicine and Clinical Research, University Hospital and University of Basel, Basel, 4051, Switzerland
| | - Klemens Ruprecht
- Department of Neurology With Experimental Neurology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, Berlin, 10117, Germany
| | - Wendy Su
- Novartis Pharma AG, Basel, 4056, Switzerland
| | - Mirja Koch
- Novartis Pharma AG, Basel, 4056, Switzerland
| | - Anke Siebert
- Department of Neurology With Experimental Neurology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, Berlin, 10117, Germany
| | | | - Nadia Tenenbaum
- EMD Serono Research and Development Institute, New York, NY, USA
| | - Jens Kuhle
- Department of Neurology, University Hospital and University of Basel, Basel, 4051, Switzerland
- Multiple Sclerosis Centre and Research Center for Clinical Neuroimmunology and Neuroscience (RC2NB), Departments of Biomedicine and Clinical Research, University Hospital and University of Basel, Basel, 4051, Switzerland
| | - Uwe Reuter
- Department of Neurology With Experimental Neurology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, Berlin, 10117, Germany.
- Department of Neurology, Universitätsmedizin Greifswald, Greifswald, 17475, Germany.
| |
Collapse
|
2
|
Cis-p-tau plays crucial role in lysolecithin-induced demyelination and subsequent axonopathy in mouse optic chiasm. Exp Neurol 2023; 359:114262. [PMID: 36343678 DOI: 10.1016/j.expneurol.2022.114262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 10/21/2022] [Accepted: 10/31/2022] [Indexed: 11/06/2022]
Abstract
Multiple sclerosis (MS) is an autoimmune demyelinating disease that leads to axon degeneration as the major cause of everlasting neurological disability. The cis-phosphorylated tau (cis-p-tau) is an isoform of tau phosphorylated on threonine 231 and causes tau fails to bind micro-tubules and promotes assembly. It gains toxic function and forms tangles in the cell which finally leads to cell death. An antibody raised against cis- p-tau (cis mAb) detects this isoform and induces its clearance. Here, we investigated the formation of cis-p-tau in a lysophosphatidylcholine (LPC)-induced prolonged demyelination model as well as the beneficial effects of its clearance using cis mAb. Cis -p-tau was increased in the lesion site, especially in axons and microglia. Behavioral and functional studies were performed using visual cliff test, visual placing test, and visual evoked potential recording. Cis-p-tau clearance resulted in decreased gliosis, protected myelin and reduced axon degeneration. Analysis of behavioral and electrophysiological data showed that clearance of cis-p-tau by cis mAb treatment improved the visual acuity along with the integrity of the optic pathway. Our results highlight the opportunity of using cis mAb as a new therapy for protecting myelin and axons in patients suffering from MS.
Collapse
|
3
|
Nelson RS, Dammer EB, Santiago JV, Seyfried NT, Rangaraju S. Brain Cell Type-Specific Nuclear Proteomics Is Imperative to Resolve Neurodegenerative Disease Mechanisms. Front Neurosci 2022; 16:902146. [PMID: 35784845 PMCID: PMC9243337 DOI: 10.3389/fnins.2022.902146] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 05/30/2022] [Indexed: 01/19/2023] Open
Abstract
Neurodegenerative diseases (NDs) involve complex cellular mechanisms that are incompletely understood. Emerging findings have revealed that disruption of nuclear processes play key roles in ND pathogenesis. The nucleus is a nexus for gene regulation and cellular processes that together, may underlie pathomechanisms of NDs. Furthermore, many genetic risk factors for NDs encode proteins that are either present in the nucleus or are involved in nuclear processes (for example, RNA binding proteins, epigenetic regulators, or nuclear-cytoplasmic transport proteins). While recent advances in nuclear transcriptomics have been significant, studies of the nuclear proteome in brain have been relatively limited. We propose that a comprehensive analysis of nuclear proteomic alterations of various brain cell types in NDs may provide novel biological and therapeutic insights. This may be feasible because emerging technical advances allow isolation and investigation of intact nuclei from post-mortem frozen human brain tissue with cell type-specific and single-cell resolution. Accordingly, nuclei of various brain cell types harbor unique protein markers which can be used to isolate cell-type specific nuclei followed by down-stream proteomics by mass spectrometry. Here we review the literature providing a rationale for investigating proteomic changes occurring in nuclei in NDs and then highlight the potential for brain cell type-specific nuclear proteomics to enhance our understanding of distinct cellular mechanisms that drive ND pathogenesis.
Collapse
Affiliation(s)
- Ruth S. Nelson
- Department of Neurology, Emory University, Atlanta, GA, United States
| | - Eric B. Dammer
- Department of Biochemistry, Emory University, Atlanta, GA, United States
| | | | | | - Srikant Rangaraju
- Department of Neurology, Emory University, Atlanta, GA, United States,*Correspondence: Srikant Rangaraju
| |
Collapse
|
4
|
Ye H, Han Y, Li P, Su Z, Huang Y. The Role of Post-Translational Modifications on the Structure and Function of Tau Protein. J Mol Neurosci 2022; 72:1557-1571. [PMID: 35325356 DOI: 10.1007/s12031-022-02002-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 03/14/2022] [Indexed: 12/14/2022]
Abstract
Involving addition of chemical groups or protein units to specific residues of the target protein, post-translational modifications (PTMs) alter the charge, hydrophobicity, and conformation of a protein, which in tune influences protein function, protein - protein interaction, and protein aggregation. While the occurrence of PTMs is dynamic and subject to regulations, conformational disorder of the target protein facilitates PTMs. The microtubule-associated protein tau is a typical intrinsically disordered protein that undergoes a variety of PTMs including phosphorylation, acetylation, ubiquitination, methylation, and oxidation. Accumulated evidence shows that these PTMs play a critical role in regulating tau-microtubule interaction, tau localization, tau degradation and aggregation, and reinforces the correlation between tau PTMs and pathogenesis of neurodegenerative disease. Here, we review tau PTMs with an emphasis on their influence on tau structure. With available biophysical characterization results, we describe how PTMs induce conformational changes in tau monomer and regulate tau aggregation. Compared to functional analysis of tau PTMs, biophysical characterization of tau PTMs is lagging. While it is challenging, characterizing the specific effects of PTMs on tau conformation and interaction is indispensable to unravel the tau PTM code.
Collapse
Affiliation(s)
- Haiqiong Ye
- Key Laboratory of Industrial Fermentation (Ministry of Education), Hubei University of Technology, Wuhan, 430068, China.,Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan, 430068, China.,Department of Biological Engineering, Hubei University of Technology, Wuhan, 430068, China
| | - Yue Han
- Key Laboratory of Industrial Fermentation (Ministry of Education), Hubei University of Technology, Wuhan, 430068, China.,Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan, 430068, China.,Department of Biological Engineering, Hubei University of Technology, Wuhan, 430068, China
| | - Ping Li
- Key Laboratory of Industrial Fermentation (Ministry of Education), Hubei University of Technology, Wuhan, 430068, China.,Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan, 430068, China.,Department of Biological Engineering, Hubei University of Technology, Wuhan, 430068, China
| | - Zhengding Su
- Key Laboratory of Industrial Fermentation (Ministry of Education), Hubei University of Technology, Wuhan, 430068, China.,Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan, 430068, China.,Department of Biological Engineering, Hubei University of Technology, Wuhan, 430068, China
| | - Yongqi Huang
- Key Laboratory of Industrial Fermentation (Ministry of Education), Hubei University of Technology, Wuhan, 430068, China. .,Hubei Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan, 430068, China. .,Department of Biological Engineering, Hubei University of Technology, Wuhan, 430068, China.
| |
Collapse
|
5
|
Shams H, Matsunaga A, Ma Q, Mofrad MR, Didonna A. Methylation at a conserved lysine residue modulates tau assembly and cellular functions. Mol Cell Neurosci 2022; 120:103707. [DOI: 10.1016/j.mcn.2022.103707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 02/14/2022] [Accepted: 02/22/2022] [Indexed: 11/30/2022] Open
|
6
|
Didonna A, Damotte V, Shams H, Matsunaga A, Caillier SJ, Dandekar R, Misra MK, Mofrad MRK, Oksenberg JR, Hollenbach JA. A splice acceptor variant in HLA-DRA affects the conformation and cellular localization of the class II DR alpha-chain. Immunology 2020; 162:194-207. [PMID: 32986852 DOI: 10.1111/imm.13273] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 09/12/2020] [Accepted: 09/14/2020] [Indexed: 01/21/2023] Open
Abstract
Class II human leucocyte antigen (HLA) proteins are involved in the immune response by presenting pathogen-derived peptides to CD4+ T lymphocytes. At the molecular level, they are constituted by α/β-heterodimers on the surface of professional antigen-presenting cells. Here, we report that the acceptor variant (rs8084) in the HLA-DRA gene mediates the transcription of an alternative version of the α-chain lacking 25 amino acids in its extracellular domain. Molecular dynamics simulations suggest this isoform undergoes structural refolding which in turn affects its stability and cellular trafficking. The short HLA-DRA isoform cannot reach the cell surface, although it is still able to bind the corresponding β-chain. Conversely, it remains entrapped within the endoplasmic reticulum where it is targeted for degradation. Furthermore, we demonstrate that the short isoform can be transported to the cell membrane via interactions with the peptide-binding site of canonical HLA heterodimers. Altogether, our findings indicate that short HLA-DRA functions as a novel intact antigen for class II HLA molecules.
Collapse
Affiliation(s)
- Alessandro Didonna
- Department of Neurology, Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA, USA
| | - Vincent Damotte
- Department of Neurology, Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA, USA
| | - Hengameh Shams
- Department of Neurology, Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA, USA
| | - Atsuko Matsunaga
- Department of Neurology, Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA, USA
| | - Stacy J Caillier
- Department of Neurology, Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA, USA
| | - Ravi Dandekar
- Department of Neurology, Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA, USA
| | - Maneesh K Misra
- Department of Neurology, Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA, USA.,Department of Pathology, The University of Chicago Medicine, Chicago, IL, USA
| | - Mohammad R K Mofrad
- Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California, Berkeley, CA, USA.,Physical Biosciences Division, Lawrence Berkeley National Lab, Berkeley, CA, USA
| | - Jorge R Oksenberg
- Department of Neurology, Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA, USA
| | - Jill A Hollenbach
- Department of Neurology, Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA, USA
| |
Collapse
|
7
|
Ma Q, Matsunaga A, Ho B, Oksenberg JR, Didonna A. Oligodendrocyte-specific Argonaute profiling identifies microRNAs associated with experimental autoimmune encephalomyelitis. J Neuroinflammation 2020; 17:297. [PMID: 33046105 PMCID: PMC7552381 DOI: 10.1186/s12974-020-01964-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 09/24/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND MicroRNAs (miRNAs) belong to a class of evolutionary conserved, non-coding small RNAs with regulatory functions on gene expression. They negatively affect the expression of target genes by promoting either RNA degradation or translational inhibition. In recent years, converging studies have identified miRNAs as key regulators of oligodendrocyte (OL) functions. OLs are the cells responsible for the formation and maintenance of myelin in the central nervous system (CNS) and represent a principal target of the autoimmune injury in multiple sclerosis (MS). METHODS MiRAP is a novel cell-specific miRNA affinity-purification technique which relies on genetically tagging Argonaut 2 (AGO2), an enzyme involved in miRNA processing. Here, we exploited miRAP potentiality to characterize OL-specific miRNA dynamics in the MS model experimental autoimmune encephalomyelitis (EAE). RESULTS We show that 20 miRNAs are differentially regulated in OLs upon transition from pre-symptomatic EAE stages to disease peak. Subsequent in vitro differentiation experiments demonstrated that a sub-group of them affects the OL maturation process, mediating either protective or detrimental signals. Lastly, transcriptome profiling highlighted the endocytosis, ferroptosis, and FoxO cascades as the pathways associated with miRNAs mediating or inhibiting OL maturation. CONCLUSIONS Altogether, our work supports a dual role for miRNAs in autoimmune demyelination. In particular, the enrichment in miRNAs mediating pro-myelinating signals suggests an active involvement of these non-coding RNAs in the homeostatic response toward neuroinflammatory injury.
Collapse
Affiliation(s)
- Qin Ma
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA
| | - Atsuko Matsunaga
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA
| | - Brenda Ho
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA
| | - Jorge R Oksenberg
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA
| | - Alessandro Didonna
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA.
| |
Collapse
|
8
|
Tau at the interface between neurodegeneration and neuroinflammation. Genes Immun 2020; 21:288-300. [PMID: 33011744 DOI: 10.1038/s41435-020-00113-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 09/16/2020] [Accepted: 09/22/2020] [Indexed: 12/21/2022]
Abstract
Tau is an evolutionary conserved protein that promotes the assembly and stabilization of microtubules in neuronal axons. Complex patterns of posttranslational modifications (PTMs) dynamically regulate tau biochemical properties and consequently its functions. An imbalance in tau PTMs has been connected with a broad spectrum of neurodegenerative conditions which are collectively known as tauopathies and include Alzheimer's disease (AD), progressive supranuclear palsy (PSP), and corticobasal degeneration (CBD) among others. The hallmark of these neurological disorders is the presence in the brain of fibrillary tangles constituted of misfolded species of hyper-phosphorylated tau. The pathological events leading to tau aggregation are still largely unknown but increasing evidence suggests that neuroinflammation plays a critical role in tangle formation. Moreover, tau aggregation itself could enhance inflammation through feed-forward mechanisms, amplifying the initial neurotoxic insults. Protective effects of tau against neuroinflammation have been also documented, adding another layer of complexity to this phenomenon. Here, we will review the current knowledge on tau regulation and function in health and disease. In particular, we will address its emerging role in connecting neurodegenerative and neuroinflammatory processes.
Collapse
|
9
|
Renschen A, Matsunaga A, Oksenberg JR, Santaniello A, Didonna A. TopoDB: a novel multifunctional management system for laboratory animal colonies. DATABASE-THE JOURNAL OF BIOLOGICAL DATABASES AND CURATION 2020; 2020:5989500. [PMID: 33206961 PMCID: PMC7673335 DOI: 10.1093/database/baaa098] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 09/22/2020] [Accepted: 10/23/2020] [Indexed: 11/14/2022]
Abstract
Animal models are widely employed in basic research to test mechanistic hypotheses in a complex biological environment as well as to evaluate the therapeutic potential of candidate compounds in preclinical settings. Rodents, and in particular mice, represent the most common in vivo models for their small size, short lifespan and possibility to manipulate their genome. Over time, a typical laboratory will develop a substantial number of inbred strains and transgenic mouse lines, requiring a substantial effort, in both logistic and economic terms, to maintain an animal colony for research purposes and to safeguard the integrity of results. To meet this need, here we present TopoDB, a robust and extensible web-based platform for the rational management of laboratory animals. TopoDB allows an easy tracking of individual animals within the colony and breeding protocols as well as the convenient storage of both genetic and phenotypic data generated in the different experiments. Altogether, these features facilitate and enhance the design of in vivo research, thus reducing the number of necessary animals and the housing costs. In summary, TopoDB represents a novel valuable tool in modern biomedical research. Database URL: https://github.com/UCSF-MS-DCC/TopoDB.
Collapse
Affiliation(s)
- Adam Renschen
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, CA 94158, USA
| | - Atsuko Matsunaga
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, CA 94158, USA
| | - Jorge R Oksenberg
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, CA 94158, USA
| | - Adam Santaniello
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, CA 94158, USA
| | - Alessandro Didonna
- Weill Institute for Neurosciences, Department of Neurology, University of California San Francisco, San Francisco, CA 94158, USA
| |
Collapse
|
10
|
Tau is required for the function of extrasynaptic NMDA receptors. Sci Rep 2019; 9:9116. [PMID: 31235881 PMCID: PMC6591308 DOI: 10.1038/s41598-019-45547-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 06/10/2019] [Indexed: 11/21/2022] Open
Abstract
Tau is a microtubule-associated neuronal protein found mainly in axons. However, increasing evidence indicates that it is also present in dendrites, where it serves as an essential mediator of synaptic NMDA (N-methyl-D-aspartate) receptor-dependent excitotoxicity. Of note, NMDA receptors can also be found outside synapses in the plasma membrane, and activation of extrasynaptic NMDA receptors has been shown to be more linked to excitotoxicity than the activation of synaptic ones. Little is known about the role of Tau in the activity of extrasynaptic NMDA receptors. Thus, we have used a Tau knockout mouse model (Tau−/− mice) to analyze the consequences of Tau absence in extrasynaptic NMDA receptor activity. We demonstrate that absence of Tau leads to a decrease in functional extrasynaptic NMDA receptors in the hippocampus. We propose that this impairment in extrasynaptic NMDA receptor activity may contribute to the well-known neuroprotective effect associated with Tau deficiency under pathological conditions.
Collapse
|