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Castro-Gomez S, Heneka MT. Innate immune activation in neurodegenerative diseases. Immunity 2024; 57:790-814. [PMID: 38599171 DOI: 10.1016/j.immuni.2024.03.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 03/11/2024] [Accepted: 03/11/2024] [Indexed: 04/12/2024]
Abstract
Activation of the innate immune system following pattern recognition receptor binding has emerged as one of the major pathogenic mechanisms in neurodegenerative disease. Experimental, epidemiological, pathological, and genetic evidence underscores the meaning of innate immune activation during the prodromal as well as clinical phases of several neurodegenerative disorders including Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, and frontotemporal dementia. Importantly, innate immune activation and the subsequent release of inflammatory mediators contribute mechanistically to other hallmarks of neurodegenerative diseases such as aberrant proteostatis, pathological protein aggregation, cytoskeleton abnormalities, altered energy homeostasis, RNA and DNA defects, and synaptic and network disbalance and ultimately to the induction of neuronal cell death. In this review, we discuss common mechanisms of innate immune activation in neurodegeneration, with particular emphasis on the pattern recognition receptors (PRRs) and other receptors involved in the detection of damage-associated molecular patterns (DAMPs).
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Affiliation(s)
- Sergio Castro-Gomez
- Center for Neurology, Department of Parkinson, Sleep and Movement Disorders, University Hospital Bonn, 53127 Bonn, Germany; Institute of Physiology II, University Hospital Bonn, 53115 Bonn, Germany
| | - Michael T Heneka
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Belval, Luxembourg; Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA, USA.
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2
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Pradeepkiran JA, Rawat P, Reddy AP, Orlov E, Reddy PH. DDQ anti-aging properties expressed with improved mitophagy in mutant tau HT22 neuronal cells. Mitochondrion 2024; 75:101843. [PMID: 38244850 DOI: 10.1016/j.mito.2024.101843] [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: 11/25/2023] [Revised: 12/28/2023] [Accepted: 01/01/2024] [Indexed: 01/22/2024]
Abstract
The purpose of our study is to develop age-related phosphorylated tau (p-tau) inhibitors, for Alzheimer's disease (AD). There are wide-ranging therapeutic molecules available in the market and tested for age-related p-tau inhibition to enhance phosphatase activity and microtubule stability in AD neurons. Until now there are no such small molecules claimed to show promising results to delay the disease process of AD. However, a recently developed molecule, DDQ, has been shown to reduce abnormal protein-protein interactions and protect neurons from mutant protein-induced toxicities in the disease process. In addition, DDQ reduced age- and Aβ-induced oxidative stress, mitochondrial dysfunction, and synaptic toxicity. To date, there are no published reports on the p-tau interaction of DDQ and Sirt3 upregulation with CREB-mediated mitophagy activation in AD neurons. In the current study, HT22 cells were transfected with mutant Tau (mTau) cDNA and treated with the novel molecule DDQ. Cell survival, immunoblotting, and immunofluorescence analysis were conducted to assess cell viability and synaptic and mitophagy proteins in treated and untreated cell groups. As expected, we found cell survival was decreased in mTau-HT22 cells when compared with control HT22 cells. However, cell survival was increased in DDQ-treated mTau-HT22 cells when compared with mTau HT22 cells. P-tau and total tau proteins were significantly reduced in DDQ-treated mTau-HT22 cells, and MAP2 levels were increased. Anti-aging proteins like Sirt3, and CREB levels were increased in DDQ-treated HT22 cells and also in mTau-HT22 cells treated DDQ. Mitophagy proteins were decreased in mTau-HT22 cells and these were increased in DDQ-treated mTau-HT22 cells. These observations strongly suggest that DDQ has anti-p-tau and anti-aging properties, via Sirt3 overexpression and increased mitophagy proteins. Our study findings may have implications for healthy aging to the development of p-tau targeted therapeutics in AD and tauopathies.
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Affiliation(s)
- Jangampalli Adi Pradeepkiran
- Internal Medicine Department, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430, United States.
| | - Priyanka Rawat
- Internal Medicine Department, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430, United States; Nutritional Sciences Department, College of Human Sciences, Texas Tech University, 1301 Akron Ave, Lubbock, TX 79409, United States
| | - Arubala P Reddy
- Nutritional Sciences Department, College of Human Sciences, Texas Tech University, 1301 Akron Ave, Lubbock, TX 79409, United States
| | - Erika Orlov
- Internal Medicine Department, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430, United States
| | - P Hemachandra Reddy
- Internal Medicine Department, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430, United States; Pharmacology & Neuroscience Department, Texas Tech University Health Sciences Center, 3601 4(th) Street, Lubbock, TX 79430, United States; Neurology Department, Texas Tech University Health Sciences Center, 3601 4(th) Street, Lubbock, TX 79430, United States; Speech, Language and Hearing Sciences Departments, Texas Tech University Health Sciences Center, 3601 4(th) Street, Lubbock, TX 79430, United States; Public Health Department, Texas Tech University Health Sciences Center, 3601 4(th) Street, Lubbock, TX 79430, United States; Nutritional Sciences Department, College of Human Sciences, Texas Tech University, 1301 Akron Ave, Lubbock, TX 79409, United States.
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Jiang Y, MacNeil LT. Simple model systems reveal conserved mechanisms of Alzheimer's disease and related tauopathies. Mol Neurodegener 2023; 18:82. [PMID: 37950311 PMCID: PMC10638731 DOI: 10.1186/s13024-023-00664-x] [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: 04/02/2023] [Accepted: 10/04/2023] [Indexed: 11/12/2023] Open
Abstract
The lack of effective therapies that slow the progression of Alzheimer's disease (AD) and related tauopathies highlights the need for a more comprehensive understanding of the fundamental cellular mechanisms underlying these diseases. Model organisms, including yeast, worms, and flies, provide simple systems with which to investigate the mechanisms of disease. The evolutionary conservation of cellular pathways regulating proteostasis and stress response in these organisms facilitates the study of genetic factors that contribute to, or protect against, neurodegeneration. Here, we review genetic modifiers of neurodegeneration and related cellular pathways identified in the budding yeast Saccharomyces cerevisiae, the nematode Caenorhabditis elegans, and the fruit fly Drosophila melanogaster, focusing on models of AD and related tauopathies. We further address the potential of simple model systems to better understand the fundamental mechanisms that lead to AD and other neurodegenerative disorders.
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Affiliation(s)
- Yuwei Jiang
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Canada
| | - Lesley T MacNeil
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Canada.
- Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, Canada.
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, 1280 Main St W, Hamilton, ON, L8S 4K1, Canada.
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Van Dam D, Valkenburg F, Van Kolen K, Pintelon I, Timmermans JP, De Deyn PP. Behavioral and Neuropathological Phenotyping of the Tau58/2 and Tau58/4 Transgenic Mouse Models for FTDP-17. Life (Basel) 2023; 13:2088. [PMID: 37895469 PMCID: PMC10608666 DOI: 10.3390/life13102088] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 10/10/2023] [Accepted: 10/16/2023] [Indexed: 10/29/2023] Open
Abstract
BACKGROUND The Tau58/2 and Tau58/4 mouse lines expressing 0N4R tau with a P301S mutation mimic aspects of frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17). In a side-by-side comparison, we report the age-dependent development of cognitive, motor, and behavioral deficits in comparison with the spatial-temporal evolution of cellular tau pathology in both models. METHODS We applied the SHIRPA primary screen and specific neuromotor, behavioral, and cognitive paradigms. The spatiotemporal development of tau pathology was investigated immunohistochemically. Levels of sarkosyl-insoluble paired helical filaments were determined via a MesoScale Discovery biomarker assay. RESULTS Neuromotor impairments developed from age 3 months in both models. On electron microscopy, spinal cord neurofibrillary pathology was visible in mice aged 3 months; however, AT8 immunoreactivity was not yet observed in Tau58/4 mice. Behavioral abnormalities and memory deficits occurred at a later stage (>9 months) when tau pathology was fully disseminated throughout the brain. Spatiotemporally, tau pathology spread from the spinal cord via the midbrain to the frontal cortex, while the hippocampus was relatively spared, thus explaining the late onset of cognitive deficits. CONCLUSIONS Our findings indicate the face and construct validity of both Tau58 models, which may provide new, valuable insights into the pathologic effects of tau species in vivo and may consequently facilitate the development of new therapeutic targets to delay or halt neurodegenerative processes occurring in tauopathies.
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Affiliation(s)
- Debby Van Dam
- Laboratory of Neurochemistry and Behavior, Experimental Neurobiology Unit, University of Antwerp, Wilrijk, 2610 Antwerp, Belgium;
- Department of Neurology and Alzheimer Center Groningen, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands
| | - Femke Valkenburg
- Laboratory of Neurochemistry and Behavior, Experimental Neurobiology Unit, University of Antwerp, Wilrijk, 2610 Antwerp, Belgium;
| | - Kristof Van Kolen
- Neuroscience Department, Janssen Research and Development, 2340 Beerse, Belgium;
| | - Isabel Pintelon
- Laboratory of Cell Biology and Histology, Department of Veterinary Sciences, University of Antwerp, 2610 Antwerp, Belgium; (I.P.); (J.-P.T.)
| | - Jean-Pierre Timmermans
- Laboratory of Cell Biology and Histology, Department of Veterinary Sciences, University of Antwerp, 2610 Antwerp, Belgium; (I.P.); (J.-P.T.)
| | - Peter Paul De Deyn
- Laboratory of Neurochemistry and Behavior, Experimental Neurobiology Unit, University of Antwerp, Wilrijk, 2610 Antwerp, Belgium;
- Department of Neurology and Alzheimer Center Groningen, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands
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Emmerson JT, Malcolm JC, Do Carmo S, Nguyen P, Breuillaud L, Martinez-Trujillo JC, Cuello AC. Neuronal loss and inflammation preceding fibrillary tau pathology in a rat model with early human-like tauopathy. Neurobiol Dis 2023; 187:106317. [PMID: 37802153 DOI: 10.1016/j.nbd.2023.106317] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 09/26/2023] [Accepted: 10/03/2023] [Indexed: 10/08/2023] Open
Abstract
In tauopathies such as Alzheimer's disease (AD) and frontotemporal dementia (FTD), the microtubule associated protein tau undergoes conformational and posttranslational modifications in a gradual, staged pathological process. While brain atrophy and cognitive decline are well-established in the advanced stages of tauopathy, it is unclear how the early pathological processes manifest prior to extensive neurodegeneration. For these studies we have applied a transgenic rat model of human-like tauopathy in its heterozygous form, named McGill-R955-hTau. The goal of the present study was to investigate whether lifelong accumulation of mutated human tau could reveal the earliest tau pathological processes in a context of advanced aging, and, at stages before the overt aggregated or fibrillary tau deposition. We characterized the phenotype of heterozygous R955-hTau rats at three endpoints, 10, 18 and 24-26 months of age, focusing on markers of cognitive capabilities, progressive tau pathology, neuronal health, neuroinflammation and brain ultrastructural integrity, using immunohistochemistry and electron microscopy. Heterozygous R955-hTau transgenic rats feature a modest, life-long accumulation of mutated human tau that led to tau hyperphosphorylation and produced deficits in learning and memory tasks after 24 months of age. Such impairments coincided with more extensive tau hyperphosphorylation in the brain at residues pThr231 and with evidence of oligomerization. Importantly, aged R955-hTau rats presented evidence of neuroinflammation, detriments to myelin morphology and detectable hippocampal neuronal loss in the absence of overt neurofibrillary lesions and brain atrophy. The slow-progressing tauopathy of R955-hTau rats should allow to better delineate the temporal progression of tau pathological events and therefore to distinguish early indicators of tauopathy as having the capability to induce degenerative events in the aged CNS.
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Affiliation(s)
- Joshua T Emmerson
- Department of Pharmacology & Therapeutics, McGill University, Montreal H3G 1Y6, Canada
| | - Janice C Malcolm
- Department of Cell Anatomy and Cell Biology, McGill University, Montreal H3A 0C7, Canada
| | - Sonia Do Carmo
- Department of Pharmacology & Therapeutics, McGill University, Montreal H3G 1Y6, Canada
| | - Phuoc Nguyen
- Department of Pharmacology & Therapeutics, McGill University, Montreal H3G 1Y6, Canada
| | - Lionel Breuillaud
- Department of Pharmacology & Therapeutics, McGill University, Montreal H3G 1Y6, Canada
| | - Julio C Martinez-Trujillo
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, Robarts Research Institute and Brain and Mind Institute, University of Western Ontario, ON N6A 5B7, Canada; Lawson Health Research Institute, London, ON N6A 5B7, Canada
| | - A Claudio Cuello
- Department of Pharmacology & Therapeutics, McGill University, Montreal H3G 1Y6, Canada; Department of Cell Anatomy and Cell Biology, McGill University, Montreal H3A 0C7, Canada; Visiting Professor, Department of Pharmacology, Oxford University, Oxford, UK, OX1 3QT.
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6
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Cummings JL, Gonzalez MI, Pritchard MC, May PC, Toledo-Sherman LM, Harris GA. The therapeutic landscape of tauopathies: challenges and prospects. Alzheimers Res Ther 2023; 15:168. [PMID: 37803386 PMCID: PMC10557207 DOI: 10.1186/s13195-023-01321-7] [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: 05/26/2023] [Accepted: 09/28/2023] [Indexed: 10/08/2023]
Abstract
Tauopathies are a group of neurodegenerative disorders characterized by the aggregation of the microtubule-associated protein tau. Aggregates of misfolded tau protein are believed to be implicated in neuronal death, which leads to a range of symptoms including cognitive decline, behavioral change, dementia, and motor deficits. Currently, there are no effective treatments for tauopathies. There are four clinical candidates in phase III trials and 16 in phase II trials. While no effective treatments are currently approved, there is increasing evidence to suggest that various therapeutic approaches may slow the progression of tauopathies or improve symptoms. This review outlines the landscape of therapeutic drugs (indexed through February 28, 2023) that target tau pathology and describes drug candidates in clinical development as well as those in the discovery and preclinical phases. The review also contains information on notable therapeutic programs that are inactive or that have been discontinued from development.
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Affiliation(s)
- Jeffrey L Cummings
- Chambers-Grundy Center for Transformative Neuroscience, Department of Brain Health, School of Integrated Health Sciences, University of Nevada, Las Vegas (UNLV), Henderson, NV, USA
| | | | | | - Patrick C May
- ADvantage Neuroscience Consulting LLC, Fort Wayne, IN, USA
| | | | - Glenn A Harris
- Rainwater Charitable Foundation, 777 Main Street, Suite 2250, Fort Worth, TX, 76102, USA.
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Emmerson JT, Do Carmo S, Liu Y, Shalhoub A, Liu A, Bonomo Q, Malcolm JC, Breuillaud L, Cuello AC. Progressive human-like tauopathy with downstream neurodegeneration and neurovascular compromise in a transgenic rat model. Neurobiol Dis 2023; 184:106227. [PMID: 37454780 DOI: 10.1016/j.nbd.2023.106227] [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: 05/02/2023] [Revised: 06/27/2023] [Accepted: 07/11/2023] [Indexed: 07/18/2023] Open
Abstract
Tauopathies, including frontotemporal dementia (FTD) and Alzheimer's disease (AD), clinically present with progressive cognitive decline and the deposition of neurofibrillary tangles (NFTs) in the brain. Neurovascular compromise is also prevalent in AD and FTD however the relationship between tau and the neurovascular unit is less understood relative to other degenerative phenotypes. Current animal models confer the ability to recapitulate aspects of the CNS tauopathies, however, existing models either display overaggressive phenotypes, or do not develop neuronal loss or genuine neurofibrillary lesions. In this report, we communicate the longitudinal characterization of brain tauopathy in a novel transgenic rat model, coded McGill-R955-hTau. The model expresses the longest isoform of human P301S tau. Homozygous R955-hTau rats displayed a robust, progressive accumulation of mutated human tau leading to the detection of tau hyperphosphorylation and cognitive deficits accelerating from 14 months of age. This model features extensive tau hyperphosphorylation with endogenous tau recruitment, authentic neurofibrillary lesions, and tau-associated neuronal loss, ventricular dilation, decreased brain volume, and gliosis in aged rats. Further, we demonstrate how neurovascular integrity becomes compromised at aged life stages using a combination of electron microscopy, injection of the tracer horseradish peroxidase and immunohistochemical approaches.
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Affiliation(s)
- Joshua T Emmerson
- Department of Pharmacology & Therapeutics, McGill University, Montreal H3G1Y6, Canada
| | - Sonia Do Carmo
- Department of Pharmacology & Therapeutics, McGill University, Montreal H3G1Y6, Canada
| | - Yingying Liu
- Department of Pharmacology & Therapeutics, McGill University, Montreal H3G1Y6, Canada
| | - Ali Shalhoub
- Department of Biochemistry, McGill University, Montreal H3A 0C7, Canada
| | - Ai Liu
- Integrated Program in Neuroscience, McGill University, Montreal H3A 1A1, Canada
| | - Quentin Bonomo
- Integrated Program in Neuroscience, McGill University, Montreal H3A 1A1, Canada
| | - Janice C Malcolm
- Department of Anatomy and Cell Biology, McGill University, Montreal H3A 0C7, Canada
| | - Lionel Breuillaud
- Department of Pharmacology & Therapeutics, McGill University, Montreal H3G1Y6, Canada
| | - A Claudio Cuello
- Department of Pharmacology & Therapeutics, McGill University, Montreal H3G1Y6, Canada; Integrated Program in Neuroscience, McGill University, Montreal H3A 1A1, Canada; Department of Pharmacology, Oxford University, Oxford OX13QT, UK.
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8
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Walton-Raaby M, Woods R, Kalyaanamoorthy S. Investigating the Theranostic Potential of Graphene Quantum Dots in Alzheimer's Disease. Int J Mol Sci 2023; 24:ijms24119476. [PMID: 37298426 DOI: 10.3390/ijms24119476] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 05/16/2023] [Accepted: 05/25/2023] [Indexed: 06/12/2023] Open
Abstract
Alzheimer's disease (AD) is one of the leading causes of death worldwide, with no definitive diagnosis or known cure. The aggregation of Tau protein into neurofibrillary tangles (NFTs), which contain straight filaments (SFs) and paired helical filaments (PHFs), is a major hallmark of AD. Graphene quantum dots (GQDs) are a type of nanomaterial that combat many of the small-molecule therapeutic challenges in AD and have shown promise in similar pathologies. In this study, two sizes of GQDs, GQD7 and GQD28, were docked to various forms of Tau monomers, SFs, and PHFs. From the favorable docked poses, we simulated each system for at least 300 ns and calculated the free energies of binding. We observed a clear preference for GQD28 in the PHF6 (306VQIVYK311) pathological hexapeptide region of monomeric Tau, while GQD7 targeted both the PHF6 and PHF6* (275VQIINK280) pathological hexapeptide regions. In SFs, GQD28 had a high affinity for a binding site that is available in AD but not in other common tauopathies, while GQD7 behaved promiscuously. In PHFs, GQD28 interacted strongly near the protofibril interface at the putative disaggregation site for epigallocatechin-3-gallate, and GQD7 largely interacted with PHF6. Our analyses revealed several key GQD binding sites that may be used for detecting, preventing, and disassembling the Tau aggregates in AD.
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Affiliation(s)
- Max Walton-Raaby
- Department of Chemistry, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Riley Woods
- Department of Chemistry, University of Waterloo, Waterloo, ON N2L 3G1, Canada
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Anglada-Huguet M, Endepols H, Sydow A, Hilgers R, Neumaier B, Drzezga A, Kaniyappan S, Mandelkow E, Mandelkow EM. Reversal of Tau-Dependent Cognitive Decay by Blocking Adenosine A1 Receptors: Comparison of Transgenic Mouse Models with Different Levels of Tauopathy. Int J Mol Sci 2023; 24:ijms24119260. [PMID: 37298211 DOI: 10.3390/ijms24119260] [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: 03/16/2023] [Revised: 05/12/2023] [Accepted: 05/12/2023] [Indexed: 06/12/2023] Open
Abstract
The accumulation of tau is a hallmark of several neurodegenerative diseases and is associated with neuronal hypoactivity and presynaptic dysfunction. Oral administration of the adenosine A1 receptor antagonist rolofylline (KW-3902) has previously been shown to reverse spatial memory deficits and to normalize the basic synaptic transmission in a mouse line expressing full-length pro-aggregant tau (TauΔK) at low levels, with late onset of disease. However, the efficacy of treatment remained to be explored for cases of more aggressive tauopathy. Using a combination of behavioral assays, imaging with several PET-tracers, and analysis of brain tissue, we compared the curative reversal of tau pathology by blocking adenosine A1 receptors in three mouse models expressing different types and levels of tau and tau mutants. We show through positron emission tomography using the tracer [18F]CPFPX (a selective A1 receptor ligand) that intravenous injection of rolofylline effectively blocks A1 receptors in the brain. Moreover, when administered to TauΔK mice, rolofylline can reverse tau pathology and synaptic decay. The beneficial effects are also observed in a line with more aggressive tau pathology, expressing the amyloidogenic repeat domain of tau (TauRDΔK) with higher aggregation propensity. Both models develop a progressive tau pathology with missorting, phosphorylation, accumulation of tau, loss of synapses, and cognitive decline. TauRDΔK causes pronounced neurofibrillary tangle assembly concomitant with neuronal death, whereas TauΔK accumulates only to tau pretangles without overt neuronal loss. A third model tested, the rTg4510 line, has a high expression of mutant TauP301L and hence a very aggressive phenotype starting at ~3 months of age. This line failed to reverse pathology upon rolofylline treatment, consistent with a higher accumulation of tau-specific PET tracers and inflammation. In conclusion, blocking adenosine A1 receptors by rolofylline can reverse pathology if the pathological potential of tau remains below a threshold value that depends on concentration and aggregation propensity.
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Affiliation(s)
- Marta Anglada-Huguet
- German Center for Neurodegenerative Diseases (DZNE), Building 99, Venusberg Campus 1, 53127 Bonn, Germany
| | - Heike Endepols
- Institute of Radiochemistry and Experimental Molecular Imaging, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany
- Department of Nuclear Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50923 Cologne, Germany
- Forschungszentrum Jülich GmbH, Institute of Neuroscience and Medicine, Nuclear Chemistry (INM-5), Wilhelm-Johnen-Straße, 52428 Jülich, Germany
| | - Astrid Sydow
- German Center for Neurodegenerative Diseases (DZNE), Building 99, Venusberg Campus 1, 53127 Bonn, Germany
| | - Ronja Hilgers
- German Center for Neurodegenerative Diseases (DZNE), Building 99, Venusberg Campus 1, 53127 Bonn, Germany
| | - Bernd Neumaier
- Institute of Radiochemistry and Experimental Molecular Imaging, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany
- Forschungszentrum Jülich GmbH, Institute of Neuroscience and Medicine, Nuclear Chemistry (INM-5), Wilhelm-Johnen-Straße, 52428 Jülich, Germany
- Max Planck Institute for Metabolism Research, 50931 Cologne, Germany
| | - Alexander Drzezga
- German Center for Neurodegenerative Diseases (DZNE), Building 99, Venusberg Campus 1, 53127 Bonn, Germany
- Department of Nuclear Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50923 Cologne, Germany
- Forschungszentrum Jülich GmbH, Institute of Neuroscience and Medicine, Molecular Organization of the Brain (INM-2), Wilhelm-Johnen-Straße, 52428 Jülich, Germany
| | - Senthilvelrajan Kaniyappan
- German Center for Neurodegenerative Diseases (DZNE), Building 99, Venusberg Campus 1, 53127 Bonn, Germany
- MPI Neurobiology Behavior-caesar, Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
- Department of Neurodegenerative Diseases and Geriatric Psychiatry, University of Bonn, 53127 Bonn, Germany
| | - Eckhard Mandelkow
- German Center for Neurodegenerative Diseases (DZNE), Building 99, Venusberg Campus 1, 53127 Bonn, Germany
- MPI Neurobiology Behavior-caesar, Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
- Department of Neurodegenerative Diseases and Geriatric Psychiatry, University of Bonn, 53127 Bonn, Germany
| | - Eva-Maria Mandelkow
- German Center for Neurodegenerative Diseases (DZNE), Building 99, Venusberg Campus 1, 53127 Bonn, Germany
- MPI Neurobiology Behavior-caesar, Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
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10
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Andrés-Benito P, Flores Á, Busquet-Areny S, Carmona M, Ausín K, Cartas-Cejudo P, Lachén-Montes M, Del Rio JA, Fernández-Irigoyen J, Santamaría E, Ferrer I. Deregulated Transcription and Proteostasis in Adult mapt Knockout Mouse. Int J Mol Sci 2023; 24:ijms24076559. [PMID: 37047532 PMCID: PMC10095510 DOI: 10.3390/ijms24076559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 03/28/2023] [Accepted: 03/28/2023] [Indexed: 04/14/2023] Open
Abstract
Transcriptomics and phosphoproteomics were carried out in the cerebral cortex of B6.Cg-Mapttm1(EGFP)Klt (tau knockout: tau-KO) and wild-type (WT) 12 month-old mice to learn about the effects of tau ablation. Compared with WT mice, tau-KO mice displayed reduced anxiety-like behavior and lower fear expression induced by aversive conditioning, whereas recognition memory remained unaltered. Cortical transcriptomic analysis revealed 69 downregulated and 105 upregulated genes in tau-KO mice, corresponding to synaptic structures, neuron cytoskeleton and transport, and extracellular matrix components. RT-qPCR validated increased mRNA levels of col6a4, gabrq, gad1, grm5, grip2, map2, rab8a, tubb3, wnt16, and an absence of map1a in tau-KO mice compared with WT mice. A few proteins were assessed with Western blotting to compare mRNA expression with corresponding protein levels. Map1a mRNA and protein levels decreased. However, β-tubulin III and GAD1 protein levels were reduced in tau-KO mice. Cortical phosphoproteomics revealed 121 hypophosphorylated and 98 hyperphosphorylated proteins in tau-KO mice. Deregulated phosphoproteins were categorized into cytoskeletal (n = 45) and membrane proteins, including proteins of the synapses and vesicles, myelin proteins, and proteins linked to membrane transport and ion channels (n = 84), proteins related to DNA and RNA metabolism (n = 36), proteins connected to the ubiquitin-proteasome system (UPS) (n = 7), proteins with kinase or phosphatase activity (n = 21), and 22 other proteins related to variegated pathways such as metabolic pathways, growth factors, or mitochondrial function or structure. The present observations reveal a complex altered brain transcriptome and phosphoproteome in tau-KO mice with only mild behavioral alterations.
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Affiliation(s)
- Pol Andrés-Benito
- Neurologic Diseases and Neurogenetics Group, Bellvitge Institute for Biomedical Research (IDIBELL), 08907 L'Hospitalet de Llobregat, Barcelona, Spain
- CIBERNED (Network Centre of Biomedical Research of Neurodegenerative Diseases), Institute of Health Carlos III, 08907 L'Hospitalet de Llobregat, Barcelona, Spain
| | - África Flores
- Neuropharmacology & Pain Group, Pharmacology Unit, Department of Pathology and Experimental Therapeutics, School of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, 08907 L'Hospitalet de Llobregat, Barcelona, Spain
| | - Sara Busquet-Areny
- Neuropathology Group, Bellvitge Institute for Biomedical Research (IDIBELL), 08907 L'Hospitalet de Llobregat, Barcelona, Spain
| | - Margarita Carmona
- CIBERNED (Network Centre of Biomedical Research of Neurodegenerative Diseases), Institute of Health Carlos III, 08907 L'Hospitalet de Llobregat, Barcelona, Spain
- Neuropathology Group, Bellvitge Institute for Biomedical Research (IDIBELL), 08907 L'Hospitalet de Llobregat, Barcelona, Spain
| | - Karina Ausín
- Clinical Neuroproteomics Unit, Proteomics Platform, Proteored-ISCIII, Navarrabiomed, Complejo Hospitalario de Navarra (CHN), Universidad Pública de Navarra (UPNA), diSNA, 31008 Pamplona, Navarra, Spain
| | - Paz Cartas-Cejudo
- Clinical Neuroproteomics Unit, Proteomics Platform, Proteored-ISCIII, Navarrabiomed, Complejo Hospitalario de Navarra (CHN), Universidad Pública de Navarra (UPNA), diSNA, 31008 Pamplona, Navarra, Spain
| | - Mercedes Lachén-Montes
- Clinical Neuroproteomics Unit, Proteomics Platform, Proteored-ISCIII, Navarrabiomed, Complejo Hospitalario de Navarra (CHN), Universidad Pública de Navarra (UPNA), diSNA, 31008 Pamplona, Navarra, Spain
| | - José Antonio Del Rio
- CIBERNED (Network Centre of Biomedical Research of Neurodegenerative Diseases), Institute of Health Carlos III, 08907 L'Hospitalet de Llobregat, Barcelona, Spain
- Molecular and Cellular Neurobiotechnology Group, Institute of Bioengineering of Catalonia (IBEC), Barcelona Institute for Science and Technology, Science Park Barcelona (PCB), 08028 Barcelona, Barcelona, Spain
| | - Joaquín Fernández-Irigoyen
- Clinical Neuroproteomics Unit, Proteomics Platform, Proteored-ISCIII, Navarrabiomed, Complejo Hospitalario de Navarra (CHN), Universidad Pública de Navarra (UPNA), diSNA, 31008 Pamplona, Navarra, Spain
| | - Enrique Santamaría
- Clinical Neuroproteomics Unit, Proteomics Platform, Proteored-ISCIII, Navarrabiomed, Complejo Hospitalario de Navarra (CHN), Universidad Pública de Navarra (UPNA), diSNA, 31008 Pamplona, Navarra, Spain
| | - Isidro Ferrer
- CIBERNED (Network Centre of Biomedical Research of Neurodegenerative Diseases), Institute of Health Carlos III, 08907 L'Hospitalet de Llobregat, Barcelona, Spain
- Neuropathology Group, Bellvitge Institute for Biomedical Research (IDIBELL), 08907 L'Hospitalet de Llobregat, Barcelona, Spain
- Department of Pathology and Experimental Therapeutics, University of Barcelona, 08907 L'Hospitalet de Llobregat, Barcelona, Spain
- Emeritus Researcher, Bellvitge Biomedical Research Institute (IDIBELL), Emeritus Professor, University of Barcelona, 08907 L'Hospitalet de Llobregat, Barcelona, Spain
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11
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I F. The unique neuropathological vulnerability of the human brain to aging. Ageing Res Rev 2023; 87:101916. [PMID: 36990284 DOI: 10.1016/j.arr.2023.101916] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 03/19/2023] [Accepted: 03/21/2023] [Indexed: 03/30/2023]
Abstract
Alzheimer's disease (AD)-related neurofibrillary tangles (NFT), argyrophilic grain disease (AGD), aging-related tau astrogliopathy (ARTAG), limbic predominant TDP-43 proteinopathy (LATE), and amygdala-predominant Lewy body disease (LBD) are proteinopathies that, together with hippocampal sclerosis, progressively appear in the elderly affecting from 50% to 99% of individuals aged 80 years, depending on the disease. These disorders usually converge on the same subject and associate with additive cognitive impairment. Abnormal Tau, TDP-43, and α-synuclein pathologies progress following a pattern consistent with an active cell-to-cell transmission and abnormal protein processing in the host cell. However, cell vulnerability and transmission pathways are specific for each disorder, albeit abnormal proteins may co-localize in particular neurons. All these alterations are unique or highly prevalent in humans. They all affect, at first, the archicortex and paleocortex to extend at later stages to the neocortex and other regions of the telencephalon. These observations show that the phylogenetically oldest areas of the human cerebral cortex and amygdala are not designed to cope with the lifespan of actual humans. New strategies aimed at reducing the functional overload of the human telencephalon, including optimization of dream repair mechanisms and implementation of artificial circuit devices to surrogate specific brain functions, appear promising.
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Affiliation(s)
- Ferrer I
- Department of Pathology and Experimental Therapeutics, University of Barcelona, Barcelona, Spain; Emeritus Researcher of the Bellvitge Institute of Biomedical Research (IDIBELL), Barcelona, Spain; Biomedical Research Network of Neurodegenerative Diseases (CIBERNED), Barcelona, Spain; Institute of Neurosciences, University of Barcelona, Barcelona, Spain; Hospitalet de Llobregat, Barcelona, Spain.
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12
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Common and Specific Marks of Different Tau Strains Following Intra-Hippocampal Injection of AD, PiD, and GGT Inoculum in hTau Transgenic Mice. Int J Mol Sci 2022; 23:ijms232415940. [PMID: 36555581 PMCID: PMC9787745 DOI: 10.3390/ijms232415940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 12/04/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022] Open
Abstract
Heterozygous hTau mice were used for the study of tau seeding. These mice express the six human tau isoforms, with a high predominance of 3Rtau over 4Rtau. The following groups were assessed: (i) non-inoculated mice aged 9 months (n = 4); (ii) Alzheimer's Disease (AD)-inoculated mice (n = 4); (iii) Globular Glial Tauopathy (GGT)-inoculated mice (n = 4); (iv) Pick's disease (PiD)-inoculated mice (n = 4); (v) control-inoculated mice (n = 4); and (vi) inoculated with vehicle alone (n = 2). AD-inoculated mice showed AT8-immunoreactive neuronal pre-tangles, granular aggregates, and dots in the CA1 region of the hippocampus, dentate gyrus (DG), and hilus, and threads and dots in the ipsilateral corpus callosum. GGT-inoculated mice showed unique or multiple AT8-immunoreactive globular deposits in neurons, occasionally extended to the proximal dendrites. PiD-inoculated mice showed a few loose pre-tangles in the CA1 region, DG, and cerebral cortex near the injection site. Coiled bodies were formed in the corpus callosum in AD-inoculated mice, but GGT-inoculated mice lacked globular glial inclusions. Tau deposits in inoculated mice co-localized active kinases p38-P and SAPK/JNK-P, thus suggesting active phosphorylation of the host tau. Tau deposits were absent in hTau mice inoculated with control homogenates and vehicle alone. Deposits in AD-inoculated hTau mice contained 3Rtau and 4Rtau; those in GGT-inoculated mice were mainly stained with anti-4Rtau antibodies, but a small number of deposits contained 3Rtau. Deposits in PiD-inoculated mice were stained with anti-3Rtau antibodies, but rare neuronal, thread-like, and dot-like deposits showed 4Rtau immunoreactivity. These findings show that tau strains produce different patterns of active neuronal seeding, which also depend on the host tau. Unexpected 3Rtau and 4Rtau deposits after inoculation of homogenates from 4R and 3R tauopathies, respectively, suggests the regulation of exon 10 splicing of the host tau during the process of seeding, thus modulating the plasticity of the cytoskeleton.
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13
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Robert A, Schöll M, Vogels T. Tau Seeding Mouse Models with Patient Brain-Derived Aggregates. Int J Mol Sci 2021; 22:6132. [PMID: 34200180 PMCID: PMC8201271 DOI: 10.3390/ijms22116132] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Revised: 05/31/2021] [Accepted: 06/01/2021] [Indexed: 12/23/2022] Open
Abstract
Tauopathies are a heterogeneous class of neurodegenerative diseases characterized by intracellular inclusions of aggregated tau proteins. Tau aggregates in different tauopathies have distinct structural features and can be found in different cell types. Transgenic animal models overexpressing human tau have been used for over two decades in the research of tau pathology. However, these models poorly recapitulate the heterogeneity of tauopathies found in human brains. Recent findings demonstrate that injection of purified tau aggregates from the brains of human tauopathy patients recapitulates both the structural features and cell-type specificity of the tau pathology of the donor tauopathy. These models may therefore have unique translational value in the study of functional consequences of tau pathology, tau-based diagnostics, and tau targeting therapeutics. This review provides an update of the literature relating to seeding-based tauopathy and their potential applications.
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Affiliation(s)
- Aiko Robert
- Department of Neurodegenerative Disease, UCL Queen Square, Institute of Neurology, University College London, London WC1N 3BG, UK; (A.R.); (M.S.)
| | - Michael Schöll
- Department of Neurodegenerative Disease, UCL Queen Square, Institute of Neurology, University College London, London WC1N 3BG, UK; (A.R.); (M.S.)
- Wallenberg Centre for Molecular and Translational Medicine and the Department of Psychiatry and Neurochemistry, University of Gothenburg, 413 45 Gothenburg, Sweden
- Department of Psychiatry and Neurochemistry, University of Gothenburg, 413 45 Gothenburg, Sweden
| | - Thomas Vogels
- Department of Neurodegenerative Disease, UCL Queen Square, Institute of Neurology, University College London, London WC1N 3BG, UK; (A.R.); (M.S.)
- Department of Psychiatry and Neurochemistry, University of Gothenburg, 413 45 Gothenburg, Sweden
- Sylics (Synaptologics B.V.), 3721 MA Bilthoven, The Netherlands
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14
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Chang CW, Shao E, Mucke L. Tau: Enabler of diverse brain disorders and target of rapidly evolving therapeutic strategies. Science 2021; 371:371/6532/eabb8255. [PMID: 33632820 DOI: 10.1126/science.abb8255] [Citation(s) in RCA: 111] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Several lines of evidence implicate the protein tau in the pathogenesis of multiple brain disorders, including Alzheimer's disease, other neurodegenerative conditions, autism, and epilepsy. Tau is abundant in neurons and interacts with microtubules, but its main functions in the brain remain to be defined. These functions may involve the regulation of signaling pathways relevant to diverse biological processes. Informative disease models have revealed a plethora of abnormal tau species and mechanisms that might contribute to neuronal dysfunction and loss, but the relative importance of their respective contributions is uncertain. This knowledge gap poses major obstacles to the development of truly impactful therapeutic strategies. The current expansion and intensification of efforts to translate mechanistic insights into tau-related therapeutics should address this issue and could deliver better treatments for a host of devastating conditions.
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Affiliation(s)
- Che-Wei Chang
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Eric Shao
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Lennart Mucke
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA. .,Department of Neurology and Weill Institute for Neurosciences, University of California, San Francisco, CA 94158, USA
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15
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Boutajangout A, Zhang W, Kim J, Abdali WA, Prelli F, Wisniewski T. Passive Immunization With a Novel Monoclonal Anti-PrP Antibody TW1 in an Alzheimer's Mouse Model With Tau Pathology. Front Aging Neurosci 2021; 13:640677. [PMID: 33716717 PMCID: PMC7947695 DOI: 10.3389/fnagi.2021.640677] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 02/03/2021] [Indexed: 11/13/2022] Open
Abstract
Neurofibrillary tangles (NFTs) are a major pathologic hallmark of Alzheimer’s disease (AD). Several studies have shown that amyloid β oligomers (Aβo) and tau oligomers mediate their toxicity, in part, via binding to cellular prion protein (PrPC) and that some anti-PrP antibodies can block this interaction. We have generated a novel monoclonal anti-PrP antibody (TW1) and assessed the efficacy of passive immunization with it in a mouse model of AD with extensive tau pathology: hTau/PS1 transgenic (Tg) mice. These mice were injected intraperitoneally once a week with TW1 starting at 5 months of age. Behavior was assessed at 8 months of age and brain tissue was subsequently harvested for analysis of treatment efficacy at 9 months. Mice treated with TW1 did not show any significant difference in sensorimotor testing including traverse beam, rotarod, and locomotor activity compared to controls. Significant cognitive benefits were observed with the novel object recognition test (ORT) in the immunized mice (two-tailed, t-test p = 0.0019). Immunized mice also showed cognitive benefits on the closed field symmetrical maze (day 1 two-tailed t-test p = 0.0001; day 2 two-tailed t-test p = 0.0015; day 3 two-tailed t-test p = 0.0002). Reduction of tau pathology was observed with PHF-1 immunohistochemistry in the piriform cortex by 60% (two-tailed t-test p = 0.01) and in the dentate gyrus by 50% (two-tailed t-test p = 0.02) in animals treated with TW1 compared to controls. There were no significant differences in astrogliosis or microgliosis observed between treated and control mice. As assessed by Western blots using PHF-1, the TW1 therapy reduced phosphorylated tau pathology (two-tailed t-test p = 0.03) and improved the ratio of pathological soluble tau to tubulin (PHF1/tubulin; two-tailed t-test p = 0.0006). Reduction of tau pathology also was observed using the CP13 antibody (two-tailed t-test p = 0.0007). These results indicate that passive immunization with the TW1 antibody can significantly decrease tau pathology as assessed by immunohistochemical and biochemical methods, resulting in improved cognitive function in a tau transgenic mouse model of AD.
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Affiliation(s)
- Allal Boutajangout
- Center for Cognitive Neurology, New York University Langone Health, New York, NY, United States.,Department of Neurology, New York University Langone Health, New York, NY, United States.,Department of Pathology, New York University Langone Health, New York, NY, United States.,Department of Physiology and Neuroscience, New York University Langone Health, New York, NY, United States
| | - Wei Zhang
- Key Laboratory of Brain Functional Genomics (Ministry of Education) Shanghai, School of Life Sciences, East China Normal University, Shanghai, China
| | - Justin Kim
- Center for Cognitive Neurology, New York University Langone Health, New York, NY, United States.,Department of Neurology, New York University Langone Health, New York, NY, United States
| | - Wed Ali Abdali
- Center for Cognitive Neurology, New York University Langone Health, New York, NY, United States.,Department of Neurology, New York University Langone Health, New York, NY, United States
| | - Frances Prelli
- Center for Cognitive Neurology, New York University Langone Health, New York, NY, United States.,Department of Neurology, New York University Langone Health, New York, NY, United States
| | - Thomas Wisniewski
- Center for Cognitive Neurology, New York University Langone Health, New York, NY, United States.,Department of Neurology, New York University Langone Health, New York, NY, United States.,Department of Pathology, New York University Langone Health, New York, NY, United States.,Department of Psychiatry, New York University Langone Health, New York, NY, United States
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16
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Soeda Y, Takashima A. New Insights Into Drug Discovery Targeting Tau Protein. Front Mol Neurosci 2020; 13:590896. [PMID: 33343298 PMCID: PMC7744460 DOI: 10.3389/fnmol.2020.590896] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 11/10/2020] [Indexed: 12/17/2022] Open
Abstract
Microtubule-associated protein tau is characterized by the fact that it is an intrinsically disordered protein due to its lack of a stable conformation and high flexibility. Intracellular inclusions of fibrillar forms of tau with a β-sheet structure accumulate in the brain of patients with Alzheimer's disease and other tauopathies. Accordingly, detachment of tau from microtubules and transition of tau from a disordered state to an abnormally aggregated state are essential events preceding the onset of tau-related diseases. Many reports have shown that this transition is caused by post-translational modifications, including hyperphosphorylation and acetylation. The misfolded tau is self-assembled and forms a tau oligomer before the appearance of tau inclusions. Animal and pathological studies using human samples have demonstrated that tau oligomer formation contributes to neuronal loss. During the progression of tauopathies, tau seeds are released from cells and incorporated into other cells, leading to the propagation of pathological tau aggregation. Accumulating evidence suggests several potential approaches for blocking tau-mediated toxicity: (1) direct inhibition of pathological tau aggregation and (2) inhibition of tau post-translational modifications that occur prior to pathological tau aggregation, (3) inhibition of tau propagation and (4) stabilization of microtubules. In addition to traditional low-molecular-weight compounds, newer drug discovery approaches such as the development of medium-molecular-weight drugs (peptide- or oligonucleotide-based drugs) and high-molecular-weight drugs (antibody-based drugs) provide alternative pathways to preventing the formation of abnormal tau. Of particular interest are recent studies suggesting that tau droplet formation by liquid-liquid phase separation may be the initial step in aberrant tau aggregation, as well results that implicate roles for tau in dendritic and nuclear functions. Here, we review the mechanisms through which drugs can target tau and consider recent clinical trials for the treatment of tauopathies. In addition, we discuss the utility of these newer strategies and propose future directions for research on tau-targeted therapeutics.
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Affiliation(s)
- Yoshiyuki Soeda
- Laboratory for Alzheimer's Disease, Department of Life Science, Faculty of Science, Gakushuin University, Tokyo, Japan
| | - Akihiko Takashima
- Laboratory for Alzheimer's Disease, Department of Life Science, Faculty of Science, Gakushuin University, Tokyo, Japan
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